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-rw-r--r--tools/fuzzing/libfuzzer/FuzzerBuiltins.h35
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerBuiltinsMsvc.h72
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerCommand.h178
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerCorpus.h533
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerCrossOver.cpp51
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp295
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h135
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerDefs.h75
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerDictionary.h118
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerDriver.cpp888
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerExtFunctions.def50
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerExtFunctions.h34
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerExtFunctionsDlsym.cpp51
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerExtFunctionsWeak.cpp54
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerExtFunctionsWindows.cpp82
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerExtraCounters.cpp42
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerFlags.def169
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerFork.cpp427
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerFork.h24
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerIO.cpp165
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerIO.h106
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp181
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp417
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerInterceptors.cpp235
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerInterface.h79
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerInternal.h175
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerLoop.cpp901
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerMain.cpp21
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerMerge.cpp419
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerMerge.h87
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerMutate.cpp562
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerMutate.h156
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerOptions.h85
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerPlatform.h163
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerRandom.h38
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerSHA1.cpp223
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerSHA1.h32
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerTracePC.cpp657
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerTracePC.h289
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtil.cpp236
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtil.h111
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtilDarwin.cpp170
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtilFuchsia.cpp565
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtilLinux.cpp41
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtilPosix.cpp185
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerUtilWindows.cpp221
-rw-r--r--tools/fuzzing/libfuzzer/FuzzerValueBitMap.h73
-rw-r--r--tools/fuzzing/libfuzzer/LICENSE.TXT68
-rwxr-xr-xtools/fuzzing/libfuzzer/clone_libfuzzer.sh36
-rw-r--r--tools/fuzzing/libfuzzer/moz.build55
-rw-r--r--tools/fuzzing/libfuzzer/patches/10-ef-runtime.patch31
-rw-r--r--tools/fuzzing/libfuzzer/patches/11-callback-rv.patch132
-rw-r--r--tools/fuzzing/libfuzzer/patches/12-custom-mutator-fail.patch53
-rw-r--r--tools/fuzzing/libfuzzer/patches/13-unused-write.patch88
-rw-r--r--tools/fuzzing/libfuzzer/patches/14-explicit-allocator.patch30
-rw-r--r--tools/fuzzing/libfuzzer/patches/15-return-to-exit.patch968
56 files changed, 11367 insertions, 0 deletions
diff --git a/tools/fuzzing/libfuzzer/FuzzerBuiltins.h b/tools/fuzzing/libfuzzer/FuzzerBuiltins.h
new file mode 100644
index 0000000000..4c0ada8266
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerBuiltins.h
@@ -0,0 +1,35 @@
+//===- FuzzerBuiltins.h - Internal header for builtins ----------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Wrapper functions and marcos around builtin functions.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_BUILTINS_H
+#define LLVM_FUZZER_BUILTINS_H
+
+#include "FuzzerPlatform.h"
+
+#if !LIBFUZZER_MSVC
+#include <cstdint>
+
+#define GET_CALLER_PC() __builtin_return_address(0)
+
+namespace fuzzer {
+
+inline uint8_t Bswap(uint8_t x) { return x; }
+inline uint16_t Bswap(uint16_t x) { return __builtin_bswap16(x); }
+inline uint32_t Bswap(uint32_t x) { return __builtin_bswap32(x); }
+inline uint64_t Bswap(uint64_t x) { return __builtin_bswap64(x); }
+
+inline uint32_t Clzll(unsigned long long X) { return __builtin_clzll(X); }
+inline uint32_t Clz(unsigned long long X) { return __builtin_clz(X); }
+inline int Popcountll(unsigned long long X) { return __builtin_popcountll(X); }
+
+} // namespace fuzzer
+
+#endif // !LIBFUZZER_MSVC
+#endif // LLVM_FUZZER_BUILTINS_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerBuiltinsMsvc.h b/tools/fuzzing/libfuzzer/FuzzerBuiltinsMsvc.h
new file mode 100644
index 0000000000..c5bec9787d
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerBuiltinsMsvc.h
@@ -0,0 +1,72 @@
+//===- FuzzerBuiltinsMSVC.h - Internal header for builtins ------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Wrapper functions and marcos that use intrinsics instead of builtin functions
+// which cannot be compiled by MSVC.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_BUILTINS_MSVC_H
+#define LLVM_FUZZER_BUILTINS_MSVC_H
+
+#include "FuzzerPlatform.h"
+
+#if LIBFUZZER_MSVC
+#include <intrin.h>
+#include <cstdint>
+#include <cstdlib>
+
+// __builtin_return_address() cannot be compiled with MSVC. Use the equivalent
+// from <intrin.h>
+#define GET_CALLER_PC() _ReturnAddress()
+
+namespace fuzzer {
+
+inline uint8_t Bswap(uint8_t x) { return x; }
+// Use alternatives to __builtin functions from <stdlib.h> and <intrin.h> on
+// Windows since the builtins are not supported by MSVC.
+inline uint16_t Bswap(uint16_t x) { return _byteswap_ushort(x); }
+inline uint32_t Bswap(uint32_t x) { return _byteswap_ulong(x); }
+inline uint64_t Bswap(uint64_t x) { return _byteswap_uint64(x); }
+
+// The functions below were mostly copied from
+// compiler-rt/lib/builtins/int_lib.h which defines the __builtin functions used
+// outside of Windows.
+inline uint32_t Clzll(uint64_t X) {
+ unsigned long LeadZeroIdx = 0;
+
+#if !defined(_M_ARM) && !defined(_M_X64)
+ // Scan the high 32 bits.
+ if (_BitScanReverse(&LeadZeroIdx, static_cast<unsigned long>(X >> 32)))
+ return static_cast<int>(63 - (LeadZeroIdx + 32)); // Create a bit offset from the MSB.
+ // Scan the low 32 bits.
+ if (_BitScanReverse(&LeadZeroIdx, static_cast<unsigned long>(X)))
+ return static_cast<int>(63 - LeadZeroIdx);
+
+#else
+ if (_BitScanReverse64(&LeadZeroIdx, X)) return 63 - LeadZeroIdx;
+#endif
+ return 64;
+}
+
+inline uint32_t Clz(uint32_t X) {
+ unsigned long LeadZeroIdx = 0;
+ if (_BitScanReverse(&LeadZeroIdx, X)) return 31 - LeadZeroIdx;
+ return 32;
+}
+
+inline int Popcountll(unsigned long long X) {
+#if !defined(_M_ARM) && !defined(_M_X64)
+ return __popcnt(X) + __popcnt(X >> 32);
+#else
+ return __popcnt64(X);
+#endif
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZER_MSVC
+#endif // LLVM_FUZZER_BUILTINS_MSVC_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerCommand.h b/tools/fuzzing/libfuzzer/FuzzerCommand.h
new file mode 100644
index 0000000000..87308864af
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerCommand.h
@@ -0,0 +1,178 @@
+//===- FuzzerCommand.h - Interface representing a process -------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// FuzzerCommand represents a command to run in a subprocess. It allows callers
+// to manage command line arguments and output and error streams.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_COMMAND_H
+#define LLVM_FUZZER_COMMAND_H
+
+#include "FuzzerDefs.h"
+#include "FuzzerIO.h"
+
+#include <algorithm>
+#include <sstream>
+#include <string>
+#include <vector>
+
+namespace fuzzer {
+
+class Command final {
+public:
+ // This command line flag is used to indicate that the remaining command line
+ // is immutable, meaning this flag effectively marks the end of the mutable
+ // argument list.
+ static inline const char *ignoreRemainingArgs() {
+ return "-ignore_remaining_args=1";
+ }
+
+ Command() : CombinedOutAndErr(false) {}
+
+ explicit Command(const Vector<std::string> &ArgsToAdd)
+ : Args(ArgsToAdd), CombinedOutAndErr(false) {}
+
+ explicit Command(const Command &Other)
+ : Args(Other.Args), CombinedOutAndErr(Other.CombinedOutAndErr),
+ OutputFile(Other.OutputFile) {}
+
+ Command &operator=(const Command &Other) {
+ Args = Other.Args;
+ CombinedOutAndErr = Other.CombinedOutAndErr;
+ OutputFile = Other.OutputFile;
+ return *this;
+ }
+
+ ~Command() {}
+
+ // Returns true if the given Arg is present in Args. Only checks up to
+ // "-ignore_remaining_args=1".
+ bool hasArgument(const std::string &Arg) const {
+ auto i = endMutableArgs();
+ return std::find(Args.begin(), i, Arg) != i;
+ }
+
+ // Gets all of the current command line arguments, **including** those after
+ // "-ignore-remaining-args=1".
+ const Vector<std::string> &getArguments() const { return Args; }
+
+ // Adds the given argument before "-ignore_remaining_args=1", or at the end
+ // if that flag isn't present.
+ void addArgument(const std::string &Arg) {
+ Args.insert(endMutableArgs(), Arg);
+ }
+
+ // Adds all given arguments before "-ignore_remaining_args=1", or at the end
+ // if that flag isn't present.
+ void addArguments(const Vector<std::string> &ArgsToAdd) {
+ Args.insert(endMutableArgs(), ArgsToAdd.begin(), ArgsToAdd.end());
+ }
+
+ // Removes the given argument from the command argument list. Ignores any
+ // occurrences after "-ignore_remaining_args=1", if present.
+ void removeArgument(const std::string &Arg) {
+ auto i = endMutableArgs();
+ Args.erase(std::remove(Args.begin(), i, Arg), i);
+ }
+
+ // Like hasArgument, but checks for "-[Flag]=...".
+ bool hasFlag(const std::string &Flag) const {
+ std::string Arg("-" + Flag + "=");
+ auto IsMatch = [&](const std::string &Other) {
+ return Arg.compare(0, std::string::npos, Other, 0, Arg.length()) == 0;
+ };
+ return std::any_of(Args.begin(), endMutableArgs(), IsMatch);
+ }
+
+ // Returns the value of the first instance of a given flag, or an empty string
+ // if the flag isn't present. Ignores any occurrences after
+ // "-ignore_remaining_args=1", if present.
+ std::string getFlagValue(const std::string &Flag) const {
+ std::string Arg("-" + Flag + "=");
+ auto IsMatch = [&](const std::string &Other) {
+ return Arg.compare(0, std::string::npos, Other, 0, Arg.length()) == 0;
+ };
+ auto i = endMutableArgs();
+ auto j = std::find_if(Args.begin(), i, IsMatch);
+ std::string result;
+ if (j != i) {
+ result = j->substr(Arg.length());
+ }
+ return result;
+ }
+
+ // Like AddArgument, but adds "-[Flag]=[Value]".
+ void addFlag(const std::string &Flag, const std::string &Value) {
+ addArgument("-" + Flag + "=" + Value);
+ }
+
+ // Like RemoveArgument, but removes "-[Flag]=...".
+ void removeFlag(const std::string &Flag) {
+ std::string Arg("-" + Flag + "=");
+ auto IsMatch = [&](const std::string &Other) {
+ return Arg.compare(0, std::string::npos, Other, 0, Arg.length()) == 0;
+ };
+ auto i = endMutableArgs();
+ Args.erase(std::remove_if(Args.begin(), i, IsMatch), i);
+ }
+
+ // Returns whether the command's stdout is being written to an output file.
+ bool hasOutputFile() const { return !OutputFile.empty(); }
+
+ // Returns the currently set output file.
+ const std::string &getOutputFile() const { return OutputFile; }
+
+ // Configures the command to redirect its output to the name file.
+ void setOutputFile(const std::string &FileName) { OutputFile = FileName; }
+
+ // Returns whether the command's stderr is redirected to stdout.
+ bool isOutAndErrCombined() const { return CombinedOutAndErr; }
+
+ // Sets whether to redirect the command's stderr to its stdout.
+ void combineOutAndErr(bool combine = true) { CombinedOutAndErr = combine; }
+
+ // Returns a string representation of the command. On many systems this will
+ // be the equivalent command line.
+ std::string toString() const {
+ std::stringstream SS;
+ for (auto arg : getArguments())
+ SS << arg << " ";
+ if (hasOutputFile())
+ SS << ">" << getOutputFile() << " ";
+ if (isOutAndErrCombined())
+ SS << "2>&1 ";
+ std::string result = SS.str();
+ if (!result.empty())
+ result = result.substr(0, result.length() - 1);
+ return result;
+ }
+
+private:
+ Command(Command &&Other) = delete;
+ Command &operator=(Command &&Other) = delete;
+
+ Vector<std::string>::iterator endMutableArgs() {
+ return std::find(Args.begin(), Args.end(), ignoreRemainingArgs());
+ }
+
+ Vector<std::string>::const_iterator endMutableArgs() const {
+ return std::find(Args.begin(), Args.end(), ignoreRemainingArgs());
+ }
+
+ // The command arguments. Args[0] is the command name.
+ Vector<std::string> Args;
+
+ // True indicates stderr is redirected to stdout.
+ bool CombinedOutAndErr;
+
+ // If not empty, stdout is redirected to the named file.
+ std::string OutputFile;
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_COMMAND_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerCorpus.h b/tools/fuzzing/libfuzzer/FuzzerCorpus.h
new file mode 100644
index 0000000000..54d1e09ec6
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerCorpus.h
@@ -0,0 +1,533 @@
+//===- FuzzerCorpus.h - Internal header for the Fuzzer ----------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::InputCorpus
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_CORPUS
+#define LLVM_FUZZER_CORPUS
+
+#include "FuzzerDataFlowTrace.h"
+#include "FuzzerDefs.h"
+#include "FuzzerIO.h"
+#include "FuzzerRandom.h"
+#include "FuzzerSHA1.h"
+#include "FuzzerTracePC.h"
+#include <algorithm>
+#include <numeric>
+#include <random>
+#include <unordered_set>
+
+namespace fuzzer {
+
+struct InputInfo {
+ Unit U; // The actual input data.
+ uint8_t Sha1[kSHA1NumBytes]; // Checksum.
+ // Number of features that this input has and no smaller input has.
+ size_t NumFeatures = 0;
+ size_t Tmp = 0; // Used by ValidateFeatureSet.
+ // Stats.
+ size_t NumExecutedMutations = 0;
+ size_t NumSuccessfullMutations = 0;
+ bool MayDeleteFile = false;
+ bool Reduced = false;
+ bool HasFocusFunction = false;
+ Vector<uint32_t> UniqFeatureSet;
+ Vector<uint8_t> DataFlowTraceForFocusFunction;
+ // Power schedule.
+ bool NeedsEnergyUpdate = false;
+ double Energy = 0.0;
+ size_t SumIncidence = 0;
+ Vector<std::pair<uint32_t, uint16_t>> FeatureFreqs;
+
+ // Delete feature Idx and its frequency from FeatureFreqs.
+ bool DeleteFeatureFreq(uint32_t Idx) {
+ if (FeatureFreqs.empty())
+ return false;
+
+ // Binary search over local feature frequencies sorted by index.
+ auto Lower = std::lower_bound(FeatureFreqs.begin(), FeatureFreqs.end(),
+ std::pair<uint32_t, uint16_t>(Idx, 0));
+
+ if (Lower != FeatureFreqs.end() && Lower->first == Idx) {
+ FeatureFreqs.erase(Lower);
+ return true;
+ }
+ return false;
+ }
+
+ // Assign more energy to a high-entropy seed, i.e., that reveals more
+ // information about the globally rare features in the neighborhood
+ // of the seed. Since we do not know the entropy of a seed that has
+ // never been executed we assign fresh seeds maximum entropy and
+ // let II->Energy approach the true entropy from above.
+ void UpdateEnergy(size_t GlobalNumberOfFeatures) {
+ Energy = 0.0;
+ SumIncidence = 0;
+
+ // Apply add-one smoothing to locally discovered features.
+ for (auto F : FeatureFreqs) {
+ size_t LocalIncidence = F.second + 1;
+ Energy -= LocalIncidence * logl(LocalIncidence);
+ SumIncidence += LocalIncidence;
+ }
+
+ // Apply add-one smoothing to locally undiscovered features.
+ // PreciseEnergy -= 0; // since logl(1.0) == 0)
+ SumIncidence += (GlobalNumberOfFeatures - FeatureFreqs.size());
+
+ // Add a single locally abundant feature apply add-one smoothing.
+ size_t AbdIncidence = NumExecutedMutations + 1;
+ Energy -= AbdIncidence * logl(AbdIncidence);
+ SumIncidence += AbdIncidence;
+
+ // Normalize.
+ if (SumIncidence != 0)
+ Energy = (Energy / SumIncidence) + logl(SumIncidence);
+ }
+
+ // Increment the frequency of the feature Idx.
+ void UpdateFeatureFrequency(uint32_t Idx) {
+ NeedsEnergyUpdate = true;
+
+ // The local feature frequencies is an ordered vector of pairs.
+ // If there are no local feature frequencies, push_back preserves order.
+ // Set the feature frequency for feature Idx32 to 1.
+ if (FeatureFreqs.empty()) {
+ FeatureFreqs.push_back(std::pair<uint32_t, uint16_t>(Idx, 1));
+ return;
+ }
+
+ // Binary search over local feature frequencies sorted by index.
+ auto Lower = std::lower_bound(FeatureFreqs.begin(), FeatureFreqs.end(),
+ std::pair<uint32_t, uint16_t>(Idx, 0));
+
+ // If feature Idx32 already exists, increment its frequency.
+ // Otherwise, insert a new pair right after the next lower index.
+ if (Lower != FeatureFreqs.end() && Lower->first == Idx) {
+ Lower->second++;
+ } else {
+ FeatureFreqs.insert(Lower, std::pair<uint32_t, uint16_t>(Idx, 1));
+ }
+ }
+};
+
+struct EntropicOptions {
+ bool Enabled;
+ size_t NumberOfRarestFeatures;
+ size_t FeatureFrequencyThreshold;
+};
+
+class InputCorpus {
+ static const uint32_t kFeatureSetSize = 1 << 21;
+ static const uint8_t kMaxMutationFactor = 20;
+ static const size_t kSparseEnergyUpdates = 100;
+
+ size_t NumExecutedMutations = 0;
+
+ EntropicOptions Entropic;
+
+public:
+ InputCorpus(const std::string &OutputCorpus, EntropicOptions Entropic)
+ : Entropic(Entropic), OutputCorpus(OutputCorpus) {
+ memset(InputSizesPerFeature, 0, sizeof(InputSizesPerFeature));
+ memset(SmallestElementPerFeature, 0, sizeof(SmallestElementPerFeature));
+ }
+ ~InputCorpus() {
+ for (auto II : Inputs)
+ delete II;
+ }
+ size_t size() const { return Inputs.size(); }
+ size_t SizeInBytes() const {
+ size_t Res = 0;
+ for (auto II : Inputs)
+ Res += II->U.size();
+ return Res;
+ }
+ size_t NumActiveUnits() const {
+ size_t Res = 0;
+ for (auto II : Inputs)
+ Res += !II->U.empty();
+ return Res;
+ }
+ size_t MaxInputSize() const {
+ size_t Res = 0;
+ for (auto II : Inputs)
+ Res = std::max(Res, II->U.size());
+ return Res;
+ }
+ void IncrementNumExecutedMutations() { NumExecutedMutations++; }
+
+ size_t NumInputsThatTouchFocusFunction() {
+ return std::count_if(Inputs.begin(), Inputs.end(), [](const InputInfo *II) {
+ return II->HasFocusFunction;
+ });
+ }
+
+ size_t NumInputsWithDataFlowTrace() {
+ return std::count_if(Inputs.begin(), Inputs.end(), [](const InputInfo *II) {
+ return !II->DataFlowTraceForFocusFunction.empty();
+ });
+ }
+
+ bool empty() const { return Inputs.empty(); }
+ const Unit &operator[] (size_t Idx) const { return Inputs[Idx]->U; }
+ InputInfo *AddToCorpus(const Unit &U, size_t NumFeatures, bool MayDeleteFile,
+ bool HasFocusFunction,
+ const Vector<uint32_t> &FeatureSet,
+ const DataFlowTrace &DFT, const InputInfo *BaseII) {
+ assert(!U.empty());
+ if (FeatureDebug)
+ Printf("ADD_TO_CORPUS %zd NF %zd\n", Inputs.size(), NumFeatures);
+ Inputs.push_back(new InputInfo());
+ InputInfo &II = *Inputs.back();
+ II.U = U;
+ II.NumFeatures = NumFeatures;
+ II.MayDeleteFile = MayDeleteFile;
+ II.UniqFeatureSet = FeatureSet;
+ II.HasFocusFunction = HasFocusFunction;
+ // Assign maximal energy to the new seed.
+ II.Energy = RareFeatures.empty() ? 1.0 : log(RareFeatures.size());
+ II.SumIncidence = RareFeatures.size();
+ II.NeedsEnergyUpdate = false;
+ std::sort(II.UniqFeatureSet.begin(), II.UniqFeatureSet.end());
+ ComputeSHA1(U.data(), U.size(), II.Sha1);
+ auto Sha1Str = Sha1ToString(II.Sha1);
+ Hashes.insert(Sha1Str);
+ if (HasFocusFunction)
+ if (auto V = DFT.Get(Sha1Str))
+ II.DataFlowTraceForFocusFunction = *V;
+ // This is a gross heuristic.
+ // Ideally, when we add an element to a corpus we need to know its DFT.
+ // But if we don't, we'll use the DFT of its base input.
+ if (II.DataFlowTraceForFocusFunction.empty() && BaseII)
+ II.DataFlowTraceForFocusFunction = BaseII->DataFlowTraceForFocusFunction;
+ DistributionNeedsUpdate = true;
+ PrintCorpus();
+ // ValidateFeatureSet();
+ return &II;
+ }
+
+ // Debug-only
+ void PrintUnit(const Unit &U) {
+ if (!FeatureDebug) return;
+ for (uint8_t C : U) {
+ if (C != 'F' && C != 'U' && C != 'Z')
+ C = '.';
+ Printf("%c", C);
+ }
+ }
+
+ // Debug-only
+ void PrintFeatureSet(const Vector<uint32_t> &FeatureSet) {
+ if (!FeatureDebug) return;
+ Printf("{");
+ for (uint32_t Feature: FeatureSet)
+ Printf("%u,", Feature);
+ Printf("}");
+ }
+
+ // Debug-only
+ void PrintCorpus() {
+ if (!FeatureDebug) return;
+ Printf("======= CORPUS:\n");
+ int i = 0;
+ for (auto II : Inputs) {
+ if (std::find(II->U.begin(), II->U.end(), 'F') != II->U.end()) {
+ Printf("[%2d] ", i);
+ Printf("%s sz=%zd ", Sha1ToString(II->Sha1).c_str(), II->U.size());
+ PrintUnit(II->U);
+ Printf(" ");
+ PrintFeatureSet(II->UniqFeatureSet);
+ Printf("\n");
+ }
+ i++;
+ }
+ }
+
+ void Replace(InputInfo *II, const Unit &U) {
+ assert(II->U.size() > U.size());
+ Hashes.erase(Sha1ToString(II->Sha1));
+ DeleteFile(*II);
+ ComputeSHA1(U.data(), U.size(), II->Sha1);
+ Hashes.insert(Sha1ToString(II->Sha1));
+ II->U = U;
+ II->Reduced = true;
+ DistributionNeedsUpdate = true;
+ }
+
+ bool HasUnit(const Unit &U) { return Hashes.count(Hash(U)); }
+ bool HasUnit(const std::string &H) { return Hashes.count(H); }
+ InputInfo &ChooseUnitToMutate(Random &Rand) {
+ InputInfo &II = *Inputs[ChooseUnitIdxToMutate(Rand)];
+ assert(!II.U.empty());
+ return II;
+ }
+
+ // Returns an index of random unit from the corpus to mutate.
+ size_t ChooseUnitIdxToMutate(Random &Rand) {
+ UpdateCorpusDistribution(Rand);
+ size_t Idx = static_cast<size_t>(CorpusDistribution(Rand));
+ assert(Idx < Inputs.size());
+ return Idx;
+ }
+
+ void PrintStats() {
+ for (size_t i = 0; i < Inputs.size(); i++) {
+ const auto &II = *Inputs[i];
+ Printf(" [% 3zd %s] sz: % 5zd runs: % 5zd succ: % 5zd focus: %d\n", i,
+ Sha1ToString(II.Sha1).c_str(), II.U.size(),
+ II.NumExecutedMutations, II.NumSuccessfullMutations, II.HasFocusFunction);
+ }
+ }
+
+ void PrintFeatureSet() {
+ for (size_t i = 0; i < kFeatureSetSize; i++) {
+ if(size_t Sz = GetFeature(i))
+ Printf("[%zd: id %zd sz%zd] ", i, SmallestElementPerFeature[i], Sz);
+ }
+ Printf("\n\t");
+ for (size_t i = 0; i < Inputs.size(); i++)
+ if (size_t N = Inputs[i]->NumFeatures)
+ Printf(" %zd=>%zd ", i, N);
+ Printf("\n");
+ }
+
+ void DeleteFile(const InputInfo &II) {
+ if (!OutputCorpus.empty() && II.MayDeleteFile)
+ RemoveFile(DirPlusFile(OutputCorpus, Sha1ToString(II.Sha1)));
+ }
+
+ void DeleteInput(size_t Idx) {
+ InputInfo &II = *Inputs[Idx];
+ DeleteFile(II);
+ Unit().swap(II.U);
+ II.Energy = 0.0;
+ II.NeedsEnergyUpdate = false;
+ DistributionNeedsUpdate = true;
+ if (FeatureDebug)
+ Printf("EVICTED %zd\n", Idx);
+ }
+
+ void AddRareFeature(uint32_t Idx) {
+ // Maintain *at least* TopXRarestFeatures many rare features
+ // and all features with a frequency below ConsideredRare.
+ // Remove all other features.
+ while (RareFeatures.size() > Entropic.NumberOfRarestFeatures &&
+ FreqOfMostAbundantRareFeature > Entropic.FeatureFrequencyThreshold) {
+
+ // Find most and second most abbundant feature.
+ uint32_t MostAbundantRareFeatureIndices[2] = {RareFeatures[0],
+ RareFeatures[0]};
+ size_t Delete = 0;
+ for (size_t i = 0; i < RareFeatures.size(); i++) {
+ uint32_t Idx2 = RareFeatures[i];
+ if (GlobalFeatureFreqs[Idx2] >=
+ GlobalFeatureFreqs[MostAbundantRareFeatureIndices[0]]) {
+ MostAbundantRareFeatureIndices[1] = MostAbundantRareFeatureIndices[0];
+ MostAbundantRareFeatureIndices[0] = Idx2;
+ Delete = i;
+ }
+ }
+
+ // Remove most abundant rare feature.
+ RareFeatures[Delete] = RareFeatures.back();
+ RareFeatures.pop_back();
+
+ for (auto II : Inputs) {
+ if (II->DeleteFeatureFreq(MostAbundantRareFeatureIndices[0]))
+ II->NeedsEnergyUpdate = true;
+ }
+
+ // Set 2nd most abundant as the new most abundant feature count.
+ FreqOfMostAbundantRareFeature =
+ GlobalFeatureFreqs[MostAbundantRareFeatureIndices[1]];
+ }
+
+ // Add rare feature, handle collisions, and update energy.
+ RareFeatures.push_back(Idx);
+ GlobalFeatureFreqs[Idx] = 0;
+ for (auto II : Inputs) {
+ II->DeleteFeatureFreq(Idx);
+
+ // Apply add-one smoothing to this locally undiscovered feature.
+ // Zero energy seeds will never be fuzzed and remain zero energy.
+ if (II->Energy > 0.0) {
+ II->SumIncidence += 1;
+ II->Energy += logl(II->SumIncidence) / II->SumIncidence;
+ }
+ }
+
+ DistributionNeedsUpdate = true;
+ }
+
+ bool AddFeature(size_t Idx, uint32_t NewSize, bool Shrink) {
+ assert(NewSize);
+ Idx = Idx % kFeatureSetSize;
+ uint32_t OldSize = GetFeature(Idx);
+ if (OldSize == 0 || (Shrink && OldSize > NewSize)) {
+ if (OldSize > 0) {
+ size_t OldIdx = SmallestElementPerFeature[Idx];
+ InputInfo &II = *Inputs[OldIdx];
+ assert(II.NumFeatures > 0);
+ II.NumFeatures--;
+ if (II.NumFeatures == 0)
+ DeleteInput(OldIdx);
+ } else {
+ NumAddedFeatures++;
+ if (Entropic.Enabled)
+ AddRareFeature((uint32_t)Idx);
+ }
+ NumUpdatedFeatures++;
+ if (FeatureDebug)
+ Printf("ADD FEATURE %zd sz %d\n", Idx, NewSize);
+ SmallestElementPerFeature[Idx] = Inputs.size();
+ InputSizesPerFeature[Idx] = NewSize;
+ return true;
+ }
+ return false;
+ }
+
+ // Increment frequency of feature Idx globally and locally.
+ void UpdateFeatureFrequency(InputInfo *II, size_t Idx) {
+ uint32_t Idx32 = Idx % kFeatureSetSize;
+
+ // Saturated increment.
+ if (GlobalFeatureFreqs[Idx32] == 0xFFFF)
+ return;
+ uint16_t Freq = GlobalFeatureFreqs[Idx32]++;
+
+ // Skip if abundant.
+ if (Freq > FreqOfMostAbundantRareFeature ||
+ std::find(RareFeatures.begin(), RareFeatures.end(), Idx32) ==
+ RareFeatures.end())
+ return;
+
+ // Update global frequencies.
+ if (Freq == FreqOfMostAbundantRareFeature)
+ FreqOfMostAbundantRareFeature++;
+
+ // Update local frequencies.
+ if (II)
+ II->UpdateFeatureFrequency(Idx32);
+ }
+
+ size_t NumFeatures() const { return NumAddedFeatures; }
+ size_t NumFeatureUpdates() const { return NumUpdatedFeatures; }
+
+private:
+
+ static const bool FeatureDebug = false;
+
+ size_t GetFeature(size_t Idx) const { return InputSizesPerFeature[Idx]; }
+
+ void ValidateFeatureSet() {
+ if (FeatureDebug)
+ PrintFeatureSet();
+ for (size_t Idx = 0; Idx < kFeatureSetSize; Idx++)
+ if (GetFeature(Idx))
+ Inputs[SmallestElementPerFeature[Idx]]->Tmp++;
+ for (auto II: Inputs) {
+ if (II->Tmp != II->NumFeatures)
+ Printf("ZZZ %zd %zd\n", II->Tmp, II->NumFeatures);
+ assert(II->Tmp == II->NumFeatures);
+ II->Tmp = 0;
+ }
+ }
+
+ // Updates the probability distribution for the units in the corpus.
+ // Must be called whenever the corpus or unit weights are changed.
+ //
+ // Hypothesis: inputs that maximize information about globally rare features
+ // are interesting.
+ void UpdateCorpusDistribution(Random &Rand) {
+ // Skip update if no seeds or rare features were added/deleted.
+ // Sparse updates for local change of feature frequencies,
+ // i.e., randomly do not skip.
+ if (!DistributionNeedsUpdate &&
+ (!Entropic.Enabled || Rand(kSparseEnergyUpdates)))
+ return;
+
+ DistributionNeedsUpdate = false;
+
+ size_t N = Inputs.size();
+ assert(N);
+ Intervals.resize(N + 1);
+ Weights.resize(N);
+ std::iota(Intervals.begin(), Intervals.end(), 0);
+
+ bool VanillaSchedule = true;
+ if (Entropic.Enabled) {
+ for (auto II : Inputs) {
+ if (II->NeedsEnergyUpdate && II->Energy != 0.0) {
+ II->NeedsEnergyUpdate = false;
+ II->UpdateEnergy(RareFeatures.size());
+ }
+ }
+
+ for (size_t i = 0; i < N; i++) {
+
+ if (Inputs[i]->NumFeatures == 0) {
+ // If the seed doesn't represent any features, assign zero energy.
+ Weights[i] = 0.;
+ } else if (Inputs[i]->NumExecutedMutations / kMaxMutationFactor >
+ NumExecutedMutations / Inputs.size()) {
+ // If the seed was fuzzed a lot more than average, assign zero energy.
+ Weights[i] = 0.;
+ } else {
+ // Otherwise, simply assign the computed energy.
+ Weights[i] = Inputs[i]->Energy;
+ }
+
+ // If energy for all seeds is zero, fall back to vanilla schedule.
+ if (Weights[i] > 0.0)
+ VanillaSchedule = false;
+ }
+ }
+
+ if (VanillaSchedule) {
+ for (size_t i = 0; i < N; i++)
+ Weights[i] = Inputs[i]->NumFeatures
+ ? (i + 1) * (Inputs[i]->HasFocusFunction ? 1000 : 1)
+ : 0.;
+ }
+
+ if (FeatureDebug) {
+ for (size_t i = 0; i < N; i++)
+ Printf("%zd ", Inputs[i]->NumFeatures);
+ Printf("SCORE\n");
+ for (size_t i = 0; i < N; i++)
+ Printf("%f ", Weights[i]);
+ Printf("Weights\n");
+ }
+ CorpusDistribution = std::piecewise_constant_distribution<double>(
+ Intervals.begin(), Intervals.end(), Weights.begin());
+ }
+ std::piecewise_constant_distribution<double> CorpusDistribution;
+
+ Vector<double> Intervals;
+ Vector<double> Weights;
+
+ std::unordered_set<std::string> Hashes;
+ Vector<InputInfo*> Inputs;
+
+ size_t NumAddedFeatures = 0;
+ size_t NumUpdatedFeatures = 0;
+ uint32_t InputSizesPerFeature[kFeatureSetSize];
+ uint32_t SmallestElementPerFeature[kFeatureSetSize];
+
+ bool DistributionNeedsUpdate = true;
+ uint16_t FreqOfMostAbundantRareFeature = 0;
+ uint16_t GlobalFeatureFreqs[kFeatureSetSize] = {};
+ Vector<uint32_t> RareFeatures;
+
+ std::string OutputCorpus;
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_CORPUS
diff --git a/tools/fuzzing/libfuzzer/FuzzerCrossOver.cpp b/tools/fuzzing/libfuzzer/FuzzerCrossOver.cpp
new file mode 100644
index 0000000000..83d9f8d47c
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerCrossOver.cpp
@@ -0,0 +1,51 @@
+//===- FuzzerCrossOver.cpp - Cross over two test inputs -------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Cross over test inputs.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDefs.h"
+#include "FuzzerMutate.h"
+#include "FuzzerRandom.h"
+#include <cstring>
+
+namespace fuzzer {
+
+// Cross Data1 and Data2, store the result (up to MaxOutSize bytes) in Out.
+size_t MutationDispatcher::CrossOver(const uint8_t *Data1, size_t Size1,
+ const uint8_t *Data2, size_t Size2,
+ uint8_t *Out, size_t MaxOutSize) {
+ assert(Size1 || Size2);
+ MaxOutSize = Rand(MaxOutSize) + 1;
+ size_t OutPos = 0;
+ size_t Pos1 = 0;
+ size_t Pos2 = 0;
+ size_t *InPos = &Pos1;
+ size_t InSize = Size1;
+ const uint8_t *Data = Data1;
+ bool CurrentlyUsingFirstData = true;
+ while (OutPos < MaxOutSize && (Pos1 < Size1 || Pos2 < Size2)) {
+ // Merge a part of Data into Out.
+ size_t OutSizeLeft = MaxOutSize - OutPos;
+ if (*InPos < InSize) {
+ size_t InSizeLeft = InSize - *InPos;
+ size_t MaxExtraSize = std::min(OutSizeLeft, InSizeLeft);
+ size_t ExtraSize = Rand(MaxExtraSize) + 1;
+ memcpy(Out + OutPos, Data + *InPos, ExtraSize);
+ OutPos += ExtraSize;
+ (*InPos) += ExtraSize;
+ }
+ // Use the other input data on the next iteration.
+ InPos = CurrentlyUsingFirstData ? &Pos2 : &Pos1;
+ InSize = CurrentlyUsingFirstData ? Size2 : Size1;
+ Data = CurrentlyUsingFirstData ? Data2 : Data1;
+ CurrentlyUsingFirstData = !CurrentlyUsingFirstData;
+ }
+ return OutPos;
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp
new file mode 100644
index 0000000000..06ea287a3c
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp
@@ -0,0 +1,295 @@
+//===- FuzzerDataFlowTrace.cpp - DataFlowTrace ---*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::DataFlowTrace
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDataFlowTrace.h"
+
+#include "FuzzerCommand.h"
+#include "FuzzerIO.h"
+#include "FuzzerRandom.h"
+#include "FuzzerSHA1.h"
+#include "FuzzerUtil.h"
+
+#include <cstdlib>
+#include <fstream>
+#include <numeric>
+#include <queue>
+#include <sstream>
+#include <string>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+
+namespace fuzzer {
+static const char *kFunctionsTxt = "functions.txt";
+
+bool BlockCoverage::AppendCoverage(const std::string &S) {
+ std::stringstream SS(S);
+ return AppendCoverage(SS);
+}
+
+// Coverage lines have this form:
+// CN X Y Z T
+// where N is the number of the function, T is the total number of instrumented
+// BBs, and X,Y,Z, if present, are the indecies of covered BB.
+// BB #0, which is the entry block, is not explicitly listed.
+bool BlockCoverage::AppendCoverage(std::istream &IN) {
+ std::string L;
+ while (std::getline(IN, L, '\n')) {
+ if (L.empty())
+ continue;
+ std::stringstream SS(L.c_str() + 1);
+ size_t FunctionId = 0;
+ SS >> FunctionId;
+ if (L[0] == 'F') {
+ FunctionsWithDFT.insert(FunctionId);
+ continue;
+ }
+ if (L[0] != 'C') continue;
+ Vector<uint32_t> CoveredBlocks;
+ while (true) {
+ uint32_t BB = 0;
+ SS >> BB;
+ if (!SS) break;
+ CoveredBlocks.push_back(BB);
+ }
+ if (CoveredBlocks.empty()) return false;
+ uint32_t NumBlocks = CoveredBlocks.back();
+ CoveredBlocks.pop_back();
+ for (auto BB : CoveredBlocks)
+ if (BB >= NumBlocks) return false;
+ auto It = Functions.find(FunctionId);
+ auto &Counters =
+ It == Functions.end()
+ ? Functions.insert({FunctionId, Vector<uint32_t>(NumBlocks)})
+ .first->second
+ : It->second;
+
+ if (Counters.size() != NumBlocks) return false; // wrong number of blocks.
+
+ Counters[0]++;
+ for (auto BB : CoveredBlocks)
+ Counters[BB]++;
+ }
+ return true;
+}
+
+// Assign weights to each function.
+// General principles:
+// * any uncovered function gets weight 0.
+// * a function with lots of uncovered blocks gets bigger weight.
+// * a function with a less frequently executed code gets bigger weight.
+Vector<double> BlockCoverage::FunctionWeights(size_t NumFunctions) const {
+ Vector<double> Res(NumFunctions);
+ for (auto It : Functions) {
+ auto FunctionID = It.first;
+ auto Counters = It.second;
+ assert(FunctionID < NumFunctions);
+ auto &Weight = Res[FunctionID];
+ // Give higher weight if the function has a DFT.
+ Weight = FunctionsWithDFT.count(FunctionID) ? 1000. : 1;
+ // Give higher weight to functions with less frequently seen basic blocks.
+ Weight /= SmallestNonZeroCounter(Counters);
+ // Give higher weight to functions with the most uncovered basic blocks.
+ Weight *= NumberOfUncoveredBlocks(Counters) + 1;
+ }
+ return Res;
+}
+
+int DataFlowTrace::ReadCoverage(const std::string &DirPath) {
+ Vector<SizedFile> Files;
+ int Res = GetSizedFilesFromDir(DirPath, &Files);
+ if (Res != 0)
+ return Res;
+ for (auto &SF : Files) {
+ auto Name = Basename(SF.File);
+ if (Name == kFunctionsTxt) continue;
+ if (!CorporaHashes.count(Name)) continue;
+ std::ifstream IF(SF.File);
+ Coverage.AppendCoverage(IF);
+ }
+ return 0;
+}
+
+static void DFTStringAppendToVector(Vector<uint8_t> *DFT,
+ const std::string &DFTString) {
+ assert(DFT->size() == DFTString.size());
+ for (size_t I = 0, Len = DFT->size(); I < Len; I++)
+ (*DFT)[I] = DFTString[I] == '1';
+}
+
+// converts a string of '0' and '1' into a Vector<uint8_t>
+static Vector<uint8_t> DFTStringToVector(const std::string &DFTString) {
+ Vector<uint8_t> DFT(DFTString.size());
+ DFTStringAppendToVector(&DFT, DFTString);
+ return DFT;
+}
+
+static bool ParseError(const char *Err, const std::string &Line) {
+ Printf("DataFlowTrace: parse error: %s: Line: %s\n", Err, Line.c_str());
+ return false;
+}
+
+// TODO(metzman): replace std::string with std::string_view for
+// better performance. Need to figure our how to use string_view on Windows.
+static bool ParseDFTLine(const std::string &Line, size_t *FunctionNum,
+ std::string *DFTString) {
+ if (!Line.empty() && Line[0] != 'F')
+ return false; // Ignore coverage.
+ size_t SpacePos = Line.find(' ');
+ if (SpacePos == std::string::npos)
+ return ParseError("no space in the trace line", Line);
+ if (Line.empty() || Line[0] != 'F')
+ return ParseError("the trace line doesn't start with 'F'", Line);
+ *FunctionNum = std::atol(Line.c_str() + 1);
+ const char *Beg = Line.c_str() + SpacePos + 1;
+ const char *End = Line.c_str() + Line.size();
+ assert(Beg < End);
+ size_t Len = End - Beg;
+ for (size_t I = 0; I < Len; I++) {
+ if (Beg[I] != '0' && Beg[I] != '1')
+ return ParseError("the trace should contain only 0 or 1", Line);
+ }
+ *DFTString = Beg;
+ return true;
+}
+
+int DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
+ Vector<SizedFile> &CorporaFiles, Random &Rand) {
+ if (DirPath.empty()) return 0;
+ Printf("INFO: DataFlowTrace: reading from '%s'\n", DirPath.c_str());
+ Vector<SizedFile> Files;
+ int Res = GetSizedFilesFromDir(DirPath, &Files);
+ if (Res != 0)
+ return Res;
+ std::string L;
+ size_t FocusFuncIdx = SIZE_MAX;
+ Vector<std::string> FunctionNames;
+
+ // Collect the hashes of the corpus files.
+ for (auto &SF : CorporaFiles)
+ CorporaHashes.insert(Hash(FileToVector(SF.File)));
+
+ // Read functions.txt
+ std::ifstream IF(DirPlusFile(DirPath, kFunctionsTxt));
+ size_t NumFunctions = 0;
+ while (std::getline(IF, L, '\n')) {
+ FunctionNames.push_back(L);
+ NumFunctions++;
+ if (*FocusFunction == L)
+ FocusFuncIdx = NumFunctions - 1;
+ }
+ if (!NumFunctions)
+ return 0;
+
+ if (*FocusFunction == "auto") {
+ // AUTOFOCUS works like this:
+ // * reads the coverage data from the DFT files.
+ // * assigns weights to functions based on coverage.
+ // * chooses a random function according to the weights.
+ Res = ReadCoverage(DirPath);
+ if (Res != 0)
+ return Res;
+ auto Weights = Coverage.FunctionWeights(NumFunctions);
+ Vector<double> Intervals(NumFunctions + 1);
+ std::iota(Intervals.begin(), Intervals.end(), 0);
+ auto Distribution = std::piecewise_constant_distribution<double>(
+ Intervals.begin(), Intervals.end(), Weights.begin());
+ FocusFuncIdx = static_cast<size_t>(Distribution(Rand));
+ *FocusFunction = FunctionNames[FocusFuncIdx];
+ assert(FocusFuncIdx < NumFunctions);
+ Printf("INFO: AUTOFOCUS: %zd %s\n", FocusFuncIdx,
+ FunctionNames[FocusFuncIdx].c_str());
+ for (size_t i = 0; i < NumFunctions; i++) {
+ if (!Weights[i]) continue;
+ Printf(" [%zd] W %g\tBB-tot %u\tBB-cov %u\tEntryFreq %u:\t%s\n", i,
+ Weights[i], Coverage.GetNumberOfBlocks(i),
+ Coverage.GetNumberOfCoveredBlocks(i), Coverage.GetCounter(i, 0),
+ FunctionNames[i].c_str());
+ }
+ }
+
+ if (!NumFunctions || FocusFuncIdx == SIZE_MAX || Files.size() <= 1)
+ return 0;
+
+ // Read traces.
+ size_t NumTraceFiles = 0;
+ size_t NumTracesWithFocusFunction = 0;
+ for (auto &SF : Files) {
+ auto Name = Basename(SF.File);
+ if (Name == kFunctionsTxt) continue;
+ if (!CorporaHashes.count(Name)) continue; // not in the corpus.
+ NumTraceFiles++;
+ // Printf("=== %s\n", Name.c_str());
+ std::ifstream IF(SF.File);
+ while (std::getline(IF, L, '\n')) {
+ size_t FunctionNum = 0;
+ std::string DFTString;
+ if (ParseDFTLine(L, &FunctionNum, &DFTString) &&
+ FunctionNum == FocusFuncIdx) {
+ NumTracesWithFocusFunction++;
+
+ if (FunctionNum >= NumFunctions) {
+ ParseError("N is greater than the number of functions", L);
+ return 0;
+ }
+ Traces[Name] = DFTStringToVector(DFTString);
+ // Print just a few small traces.
+ if (NumTracesWithFocusFunction <= 3 && DFTString.size() <= 16)
+ Printf("%s => |%s|\n", Name.c_str(), std::string(DFTString).c_str());
+ break; // No need to parse the following lines.
+ }
+ }
+ }
+ Printf("INFO: DataFlowTrace: %zd trace files, %zd functions, "
+ "%zd traces with focus function\n",
+ NumTraceFiles, NumFunctions, NumTracesWithFocusFunction);
+ return 0;
+}
+
+int CollectDataFlow(const std::string &DFTBinary, const std::string &DirPath,
+ const Vector<SizedFile> &CorporaFiles) {
+ Printf("INFO: collecting data flow: bin: %s dir: %s files: %zd\n",
+ DFTBinary.c_str(), DirPath.c_str(), CorporaFiles.size());
+ if (CorporaFiles.empty()) {
+ Printf("ERROR: can't collect data flow without corpus provided.");
+ return 1;
+ }
+
+ static char DFSanEnv[] = "DFSAN_OPTIONS=warn_unimplemented=0";
+ putenv(DFSanEnv);
+ MkDir(DirPath);
+ for (auto &F : CorporaFiles) {
+ // For every input F we need to collect the data flow and the coverage.
+ // Data flow collection may fail if we request too many DFSan tags at once.
+ // So, we start from requesting all tags in range [0,Size) and if that fails
+ // we then request tags in [0,Size/2) and [Size/2, Size), and so on.
+ // Function number => DFT.
+ auto OutPath = DirPlusFile(DirPath, Hash(FileToVector(F.File)));
+ std::unordered_map<size_t, Vector<uint8_t>> DFTMap;
+ std::unordered_set<std::string> Cov;
+ Command Cmd;
+ Cmd.addArgument(DFTBinary);
+ Cmd.addArgument(F.File);
+ Cmd.addArgument(OutPath);
+ Printf("CMD: %s\n", Cmd.toString().c_str());
+ ExecuteCommand(Cmd);
+ }
+ // Write functions.txt if it's currently empty or doesn't exist.
+ auto FunctionsTxtPath = DirPlusFile(DirPath, kFunctionsTxt);
+ if (FileToString(FunctionsTxtPath).empty()) {
+ Command Cmd;
+ Cmd.addArgument(DFTBinary);
+ Cmd.setOutputFile(FunctionsTxtPath);
+ ExecuteCommand(Cmd);
+ }
+ return 0;
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h
new file mode 100644
index 0000000000..767bad24f1
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h
@@ -0,0 +1,135 @@
+//===- FuzzerDataFlowTrace.h - Internal header for the Fuzzer ---*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::DataFlowTrace; reads and handles a data-flow trace.
+//
+// A data flow trace is generated by e.g. dataflow/DataFlow.cpp
+// and is stored on disk in a separate directory.
+//
+// The trace dir contains a file 'functions.txt' which lists function names,
+// oner per line, e.g.
+// ==> functions.txt <==
+// Func2
+// LLVMFuzzerTestOneInput
+// Func1
+//
+// All other files in the dir are the traces, see dataflow/DataFlow.cpp.
+// The name of the file is sha1 of the input used to generate the trace.
+//
+// Current status:
+// the data is parsed and the summary is printed, but the data is not yet
+// used in any other way.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_DATA_FLOW_TRACE
+#define LLVM_FUZZER_DATA_FLOW_TRACE
+
+#include "FuzzerDefs.h"
+#include "FuzzerIO.h"
+
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+#include <string>
+
+namespace fuzzer {
+
+int CollectDataFlow(const std::string &DFTBinary, const std::string &DirPath,
+ const Vector<SizedFile> &CorporaFiles);
+
+class BlockCoverage {
+ public:
+ bool AppendCoverage(std::istream &IN);
+ bool AppendCoverage(const std::string &S);
+
+ size_t NumCoveredFunctions() const { return Functions.size(); }
+
+ uint32_t GetCounter(size_t FunctionId, size_t BasicBlockId) {
+ auto It = Functions.find(FunctionId);
+ if (It == Functions.end()) return 0;
+ const auto &Counters = It->second;
+ if (BasicBlockId < Counters.size())
+ return Counters[BasicBlockId];
+ return 0;
+ }
+
+ uint32_t GetNumberOfBlocks(size_t FunctionId) {
+ auto It = Functions.find(FunctionId);
+ if (It == Functions.end()) return 0;
+ const auto &Counters = It->second;
+ return Counters.size();
+ }
+
+ uint32_t GetNumberOfCoveredBlocks(size_t FunctionId) {
+ auto It = Functions.find(FunctionId);
+ if (It == Functions.end()) return 0;
+ const auto &Counters = It->second;
+ uint32_t Result = 0;
+ for (auto Cnt: Counters)
+ if (Cnt)
+ Result++;
+ return Result;
+ }
+
+ Vector<double> FunctionWeights(size_t NumFunctions) const;
+ void clear() { Functions.clear(); }
+
+ private:
+
+ typedef Vector<uint32_t> CoverageVector;
+
+ uint32_t NumberOfCoveredBlocks(const CoverageVector &Counters) const {
+ uint32_t Res = 0;
+ for (auto Cnt : Counters)
+ if (Cnt)
+ Res++;
+ return Res;
+ }
+
+ uint32_t NumberOfUncoveredBlocks(const CoverageVector &Counters) const {
+ return Counters.size() - NumberOfCoveredBlocks(Counters);
+ }
+
+ uint32_t SmallestNonZeroCounter(const CoverageVector &Counters) const {
+ assert(!Counters.empty());
+ uint32_t Res = Counters[0];
+ for (auto Cnt : Counters)
+ if (Cnt)
+ Res = Min(Res, Cnt);
+ assert(Res);
+ return Res;
+ }
+
+ // Function ID => vector of counters.
+ // Each counter represents how many input files trigger the given basic block.
+ std::unordered_map<size_t, CoverageVector> Functions;
+ // Functions that have DFT entry.
+ std::unordered_set<size_t> FunctionsWithDFT;
+};
+
+class DataFlowTrace {
+ public:
+ int ReadCoverage(const std::string &DirPath);
+ int Init(const std::string &DirPath, std::string *FocusFunction,
+ Vector<SizedFile> &CorporaFiles, Random &Rand);
+ void Clear() { Traces.clear(); }
+ const Vector<uint8_t> *Get(const std::string &InputSha1) const {
+ auto It = Traces.find(InputSha1);
+ if (It != Traces.end())
+ return &It->second;
+ return nullptr;
+ }
+
+ private:
+ // Input's sha1 => DFT for the FocusFunction.
+ std::unordered_map<std::string, Vector<uint8_t> > Traces;
+ BlockCoverage Coverage;
+ std::unordered_set<std::string> CorporaHashes;
+};
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_DATA_FLOW_TRACE
diff --git a/tools/fuzzing/libfuzzer/FuzzerDefs.h b/tools/fuzzing/libfuzzer/FuzzerDefs.h
new file mode 100644
index 0000000000..3952ac51ef
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerDefs.h
@@ -0,0 +1,75 @@
+//===- FuzzerDefs.h - Internal header for the Fuzzer ------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Basic definitions.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_DEFS_H
+#define LLVM_FUZZER_DEFS_H
+
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+#include <memory>
+#include <set>
+#include <string>
+#include <vector>
+
+
+namespace fuzzer {
+
+template <class T> T Min(T a, T b) { return a < b ? a : b; }
+template <class T> T Max(T a, T b) { return a > b ? a : b; }
+
+class Random;
+class Dictionary;
+class DictionaryEntry;
+class MutationDispatcher;
+struct FuzzingOptions;
+class InputCorpus;
+struct InputInfo;
+struct ExternalFunctions;
+
+// Global interface to functions that may or may not be available.
+extern ExternalFunctions *EF;
+
+// We are using a custom allocator to give a different symbol name to STL
+// containers in order to avoid ODR violations.
+template<typename T>
+ class fuzzer_allocator: public std::allocator<T> {
+ public:
+ fuzzer_allocator() = default;
+
+ template<class U>
+ explicit fuzzer_allocator(const fuzzer_allocator<U>&) {}
+
+ template<class Other>
+ struct rebind { typedef fuzzer_allocator<Other> other; };
+ };
+
+template<typename T>
+using Vector = std::vector<T, fuzzer_allocator<T>>;
+
+template<typename T>
+using Set = std::set<T, std::less<T>, fuzzer_allocator<T>>;
+
+typedef Vector<uint8_t> Unit;
+typedef Vector<Unit> UnitVector;
+typedef int (*UserCallback)(const uint8_t *Data, size_t Size);
+
+int FuzzerDriver(int *argc, char ***argv, UserCallback Callback);
+
+uint8_t *ExtraCountersBegin();
+uint8_t *ExtraCountersEnd();
+void ClearExtraCounters();
+
+extern bool RunningUserCallback;
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_DEFS_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerDictionary.h b/tools/fuzzing/libfuzzer/FuzzerDictionary.h
new file mode 100644
index 0000000000..301c5d9afe
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerDictionary.h
@@ -0,0 +1,118 @@
+//===- FuzzerDictionary.h - Internal header for the Fuzzer ------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::Dictionary
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_DICTIONARY_H
+#define LLVM_FUZZER_DICTIONARY_H
+
+#include "FuzzerDefs.h"
+#include "FuzzerIO.h"
+#include "FuzzerUtil.h"
+#include <algorithm>
+#include <limits>
+
+namespace fuzzer {
+// A simple POD sized array of bytes.
+template <size_t kMaxSizeT> class FixedWord {
+public:
+ static const size_t kMaxSize = kMaxSizeT;
+ FixedWord() {}
+ FixedWord(const uint8_t *B, uint8_t S) { Set(B, S); }
+
+ void Set(const uint8_t *B, uint8_t S) {
+ assert(S <= kMaxSize);
+ memcpy(Data, B, S);
+ Size = S;
+ }
+
+ bool operator==(const FixedWord<kMaxSize> &w) const {
+ return Size == w.Size && 0 == memcmp(Data, w.Data, Size);
+ }
+
+ static size_t GetMaxSize() { return kMaxSize; }
+ const uint8_t *data() const { return Data; }
+ uint8_t size() const { return Size; }
+
+private:
+ uint8_t Size = 0;
+ uint8_t Data[kMaxSize];
+};
+
+typedef FixedWord<64> Word;
+
+class DictionaryEntry {
+ public:
+ DictionaryEntry() {}
+ DictionaryEntry(Word W) : W(W) {}
+ DictionaryEntry(Word W, size_t PositionHint) : W(W), PositionHint(PositionHint) {}
+ const Word &GetW() const { return W; }
+
+ bool HasPositionHint() const { return PositionHint != std::numeric_limits<size_t>::max(); }
+ size_t GetPositionHint() const {
+ assert(HasPositionHint());
+ return PositionHint;
+ }
+ void IncUseCount() { UseCount++; }
+ void IncSuccessCount() { SuccessCount++; }
+ size_t GetUseCount() const { return UseCount; }
+ size_t GetSuccessCount() const {return SuccessCount; }
+
+ void Print(const char *PrintAfter = "\n") {
+ PrintASCII(W.data(), W.size());
+ if (HasPositionHint())
+ Printf("@%zd", GetPositionHint());
+ Printf("%s", PrintAfter);
+ }
+
+private:
+ Word W;
+ size_t PositionHint = std::numeric_limits<size_t>::max();
+ size_t UseCount = 0;
+ size_t SuccessCount = 0;
+};
+
+class Dictionary {
+ public:
+ static const size_t kMaxDictSize = 1 << 14;
+
+ bool ContainsWord(const Word &W) const {
+ return std::any_of(begin(), end(), [&](const DictionaryEntry &DE) {
+ return DE.GetW() == W;
+ });
+ }
+ const DictionaryEntry *begin() const { return &DE[0]; }
+ const DictionaryEntry *end() const { return begin() + Size; }
+ DictionaryEntry & operator[] (size_t Idx) {
+ assert(Idx < Size);
+ return DE[Idx];
+ }
+ void push_back(DictionaryEntry DE) {
+ if (Size < kMaxDictSize)
+ this->DE[Size++] = DE;
+ }
+ void clear() { Size = 0; }
+ bool empty() const { return Size == 0; }
+ size_t size() const { return Size; }
+
+private:
+ DictionaryEntry DE[kMaxDictSize];
+ size_t Size = 0;
+};
+
+// Parses one dictionary entry.
+// If successful, write the enty to Unit and returns true,
+// otherwise returns false.
+bool ParseOneDictionaryEntry(const std::string &Str, Unit *U);
+// Parses the dictionary file, fills Units, returns true iff all lines
+// were parsed successfully.
+bool ParseDictionaryFile(const std::string &Text, Vector<Unit> *Units);
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_DICTIONARY_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerDriver.cpp b/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
new file mode 100644
index 0000000000..bedad16efa
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
@@ -0,0 +1,888 @@
+//===- FuzzerDriver.cpp - FuzzerDriver function and flags -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// FuzzerDriver and flag parsing.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerCommand.h"
+#include "FuzzerCorpus.h"
+#include "FuzzerFork.h"
+#include "FuzzerIO.h"
+#include "FuzzerInterface.h"
+#include "FuzzerInternal.h"
+#include "FuzzerMerge.h"
+#include "FuzzerMutate.h"
+#include "FuzzerPlatform.h"
+#include "FuzzerRandom.h"
+#include "FuzzerTracePC.h"
+#include <algorithm>
+#include <atomic>
+#include <chrono>
+#include <cstdlib>
+#include <cstring>
+#include <mutex>
+#include <string>
+#include <thread>
+#include <fstream>
+
+// This function should be present in the libFuzzer so that the client
+// binary can test for its existence.
+#if LIBFUZZER_MSVC
+extern "C" void __libfuzzer_is_present() {}
+#if defined(_M_IX86) || defined(__i386__)
+#pragma comment(linker, "/include:___libfuzzer_is_present")
+#else
+#pragma comment(linker, "/include:__libfuzzer_is_present")
+#endif
+#else
+extern "C" __attribute__((used)) void __libfuzzer_is_present() {}
+#endif // LIBFUZZER_MSVC
+
+namespace fuzzer {
+
+// Program arguments.
+struct FlagDescription {
+ const char *Name;
+ const char *Description;
+ int Default;
+ int *IntFlag;
+ const char **StrFlag;
+ unsigned int *UIntFlag;
+};
+
+struct {
+#define FUZZER_DEPRECATED_FLAG(Name)
+#define FUZZER_FLAG_INT(Name, Default, Description) int Name;
+#define FUZZER_FLAG_UNSIGNED(Name, Default, Description) unsigned int Name;
+#define FUZZER_FLAG_STRING(Name, Description) const char *Name;
+#include "FuzzerFlags.def"
+#undef FUZZER_DEPRECATED_FLAG
+#undef FUZZER_FLAG_INT
+#undef FUZZER_FLAG_UNSIGNED
+#undef FUZZER_FLAG_STRING
+} Flags;
+
+static const FlagDescription FlagDescriptions [] {
+#define FUZZER_DEPRECATED_FLAG(Name) \
+ {#Name, "Deprecated; don't use", 0, nullptr, nullptr, nullptr},
+#define FUZZER_FLAG_INT(Name, Default, Description) \
+ {#Name, Description, Default, &Flags.Name, nullptr, nullptr},
+#define FUZZER_FLAG_UNSIGNED(Name, Default, Description) \
+ {#Name, Description, static_cast<int>(Default), \
+ nullptr, nullptr, &Flags.Name},
+#define FUZZER_FLAG_STRING(Name, Description) \
+ {#Name, Description, 0, nullptr, &Flags.Name, nullptr},
+#include "FuzzerFlags.def"
+#undef FUZZER_DEPRECATED_FLAG
+#undef FUZZER_FLAG_INT
+#undef FUZZER_FLAG_UNSIGNED
+#undef FUZZER_FLAG_STRING
+};
+
+static const size_t kNumFlags =
+ sizeof(FlagDescriptions) / sizeof(FlagDescriptions[0]);
+
+static Vector<std::string> *Inputs;
+static std::string *ProgName;
+
+static void PrintHelp() {
+ Printf("Usage:\n");
+ auto Prog = ProgName->c_str();
+ Printf("\nTo run fuzzing pass 0 or more directories.\n");
+ Printf("%s [-flag1=val1 [-flag2=val2 ...] ] [dir1 [dir2 ...] ]\n", Prog);
+
+ Printf("\nTo run individual tests without fuzzing pass 1 or more files:\n");
+ Printf("%s [-flag1=val1 [-flag2=val2 ...] ] file1 [file2 ...]\n", Prog);
+
+ Printf("\nFlags: (strictly in form -flag=value)\n");
+ size_t MaxFlagLen = 0;
+ for (size_t F = 0; F < kNumFlags; F++)
+ MaxFlagLen = std::max(strlen(FlagDescriptions[F].Name), MaxFlagLen);
+
+ for (size_t F = 0; F < kNumFlags; F++) {
+ const auto &D = FlagDescriptions[F];
+ if (strstr(D.Description, "internal flag") == D.Description) continue;
+ Printf(" %s", D.Name);
+ for (size_t i = 0, n = MaxFlagLen - strlen(D.Name); i < n; i++)
+ Printf(" ");
+ Printf("\t");
+ Printf("%d\t%s\n", D.Default, D.Description);
+ }
+ Printf("\nFlags starting with '--' will be ignored and "
+ "will be passed verbatim to subprocesses.\n");
+}
+
+static const char *FlagValue(const char *Param, const char *Name) {
+ size_t Len = strlen(Name);
+ if (Param[0] == '-' && strstr(Param + 1, Name) == Param + 1 &&
+ Param[Len + 1] == '=')
+ return &Param[Len + 2];
+ return nullptr;
+}
+
+// Avoid calling stol as it triggers a bug in clang/glibc build.
+static long MyStol(const char *Str) {
+ long Res = 0;
+ long Sign = 1;
+ if (*Str == '-') {
+ Str++;
+ Sign = -1;
+ }
+ for (size_t i = 0; Str[i]; i++) {
+ char Ch = Str[i];
+ if (Ch < '0' || Ch > '9')
+ return Res;
+ Res = Res * 10 + (Ch - '0');
+ }
+ return Res * Sign;
+}
+
+static bool ParseOneFlag(const char *Param) {
+ if (Param[0] != '-') return false;
+ if (Param[1] == '-') {
+ static bool PrintedWarning = false;
+ if (!PrintedWarning) {
+ PrintedWarning = true;
+ Printf("INFO: libFuzzer ignores flags that start with '--'\n");
+ }
+ for (size_t F = 0; F < kNumFlags; F++)
+ if (FlagValue(Param + 1, FlagDescriptions[F].Name))
+ Printf("WARNING: did you mean '%s' (single dash)?\n", Param + 1);
+ return true;
+ }
+ for (size_t F = 0; F < kNumFlags; F++) {
+ const char *Name = FlagDescriptions[F].Name;
+ const char *Str = FlagValue(Param, Name);
+ if (Str) {
+ if (FlagDescriptions[F].IntFlag) {
+ int Val = MyStol(Str);
+ *FlagDescriptions[F].IntFlag = Val;
+ if (Flags.verbosity >= 2)
+ Printf("Flag: %s %d\n", Name, Val);
+ return true;
+ } else if (FlagDescriptions[F].UIntFlag) {
+ unsigned int Val = std::stoul(Str);
+ *FlagDescriptions[F].UIntFlag = Val;
+ if (Flags.verbosity >= 2)
+ Printf("Flag: %s %u\n", Name, Val);
+ return true;
+ } else if (FlagDescriptions[F].StrFlag) {
+ *FlagDescriptions[F].StrFlag = Str;
+ if (Flags.verbosity >= 2)
+ Printf("Flag: %s %s\n", Name, Str);
+ return true;
+ } else { // Deprecated flag.
+ Printf("Flag: %s: deprecated, don't use\n", Name);
+ return true;
+ }
+ }
+ }
+ Printf("\n\nWARNING: unrecognized flag '%s'; "
+ "use -help=1 to list all flags\n\n", Param);
+ return true;
+}
+
+// We don't use any library to minimize dependencies.
+static void ParseFlags(const Vector<std::string> &Args,
+ const ExternalFunctions *EF) {
+ for (size_t F = 0; F < kNumFlags; F++) {
+ if (FlagDescriptions[F].IntFlag)
+ *FlagDescriptions[F].IntFlag = FlagDescriptions[F].Default;
+ if (FlagDescriptions[F].UIntFlag)
+ *FlagDescriptions[F].UIntFlag =
+ static_cast<unsigned int>(FlagDescriptions[F].Default);
+ if (FlagDescriptions[F].StrFlag)
+ *FlagDescriptions[F].StrFlag = nullptr;
+ }
+
+ // Disable len_control by default, if LLVMFuzzerCustomMutator is used.
+ if (EF->LLVMFuzzerCustomMutator) {
+ Flags.len_control = 0;
+ Printf("INFO: found LLVMFuzzerCustomMutator (%p). "
+ "Disabling -len_control by default.\n", EF->LLVMFuzzerCustomMutator);
+ }
+
+ Inputs = new Vector<std::string>;
+ for (size_t A = 1; A < Args.size(); A++) {
+ if (ParseOneFlag(Args[A].c_str())) {
+ if (Flags.ignore_remaining_args)
+ break;
+ continue;
+ }
+ Inputs->push_back(Args[A]);
+ }
+}
+
+static std::mutex Mu;
+
+static void PulseThread() {
+ while (true) {
+ SleepSeconds(600);
+ std::lock_guard<std::mutex> Lock(Mu);
+ Printf("pulse...\n");
+ }
+}
+
+static void WorkerThread(const Command &BaseCmd, std::atomic<unsigned> *Counter,
+ unsigned NumJobs, std::atomic<bool> *HasErrors) {
+ while (true) {
+ unsigned C = (*Counter)++;
+ if (C >= NumJobs) break;
+ std::string Log = "fuzz-" + std::to_string(C) + ".log";
+ Command Cmd(BaseCmd);
+ Cmd.setOutputFile(Log);
+ Cmd.combineOutAndErr();
+ if (Flags.verbosity) {
+ std::string CommandLine = Cmd.toString();
+ Printf("%s\n", CommandLine.c_str());
+ }
+ int ExitCode = ExecuteCommand(Cmd);
+ if (ExitCode != 0)
+ *HasErrors = true;
+ std::lock_guard<std::mutex> Lock(Mu);
+ Printf("================== Job %u exited with exit code %d ============\n",
+ C, ExitCode);
+ fuzzer::CopyFileToErr(Log);
+ }
+}
+
+std::string CloneArgsWithoutX(const Vector<std::string> &Args,
+ const char *X1, const char *X2) {
+ std::string Cmd;
+ for (auto &S : Args) {
+ if (FlagValue(S.c_str(), X1) || FlagValue(S.c_str(), X2))
+ continue;
+ Cmd += S + " ";
+ }
+ return Cmd;
+}
+
+static int RunInMultipleProcesses(const Vector<std::string> &Args,
+ unsigned NumWorkers, unsigned NumJobs) {
+ std::atomic<unsigned> Counter(0);
+ std::atomic<bool> HasErrors(false);
+ Command Cmd(Args);
+ Cmd.removeFlag("jobs");
+ Cmd.removeFlag("workers");
+ Vector<std::thread> V;
+ std::thread Pulse(PulseThread);
+ Pulse.detach();
+ for (unsigned i = 0; i < NumWorkers; i++)
+ V.push_back(std::thread(WorkerThread, std::ref(Cmd), &Counter, NumJobs, &HasErrors));
+ for (auto &T : V)
+ T.join();
+ return HasErrors ? 1 : 0;
+}
+
+static void RssThread(Fuzzer *F, size_t RssLimitMb) {
+ while (true) {
+ SleepSeconds(1);
+ size_t Peak = GetPeakRSSMb();
+ if (Peak > RssLimitMb)
+ F->RssLimitCallback();
+ }
+}
+
+static void StartRssThread(Fuzzer *F, size_t RssLimitMb) {
+ if (!RssLimitMb)
+ return;
+ std::thread T(RssThread, F, RssLimitMb);
+ T.detach();
+}
+
+int RunOneTest(Fuzzer *F, const char *InputFilePath, size_t MaxLen) {
+ Unit U = FileToVector(InputFilePath);
+ if (MaxLen && MaxLen < U.size())
+ U.resize(MaxLen);
+ F->ExecuteCallback(U.data(), U.size());
+ F->TryDetectingAMemoryLeak(U.data(), U.size(), true);
+ return 0;
+}
+
+static bool AllInputsAreFiles() {
+ if (Inputs->empty()) return false;
+ for (auto &Path : *Inputs)
+ if (!IsFile(Path))
+ return false;
+ return true;
+}
+
+static std::string GetDedupTokenFromCmdOutput(const std::string &S) {
+ auto Beg = S.find("DEDUP_TOKEN:");
+ if (Beg == std::string::npos)
+ return "";
+ auto End = S.find('\n', Beg);
+ if (End == std::string::npos)
+ return "";
+ return S.substr(Beg, End - Beg);
+}
+
+int CleanseCrashInput(const Vector<std::string> &Args,
+ const FuzzingOptions &Options) {
+ if (Inputs->size() != 1 || !Flags.exact_artifact_path) {
+ Printf("ERROR: -cleanse_crash should be given one input file and"
+ " -exact_artifact_path\n");
+ return 1;
+ }
+ std::string InputFilePath = Inputs->at(0);
+ std::string OutputFilePath = Flags.exact_artifact_path;
+ Command Cmd(Args);
+ Cmd.removeFlag("cleanse_crash");
+
+ assert(Cmd.hasArgument(InputFilePath));
+ Cmd.removeArgument(InputFilePath);
+
+ auto TmpFilePath = TempPath("CleanseCrashInput", ".repro");
+ Cmd.addArgument(TmpFilePath);
+ Cmd.setOutputFile(getDevNull());
+ Cmd.combineOutAndErr();
+
+ std::string CurrentFilePath = InputFilePath;
+ auto U = FileToVector(CurrentFilePath);
+ size_t Size = U.size();
+
+ const Vector<uint8_t> ReplacementBytes = {' ', 0xff};
+ for (int NumAttempts = 0; NumAttempts < 5; NumAttempts++) {
+ bool Changed = false;
+ for (size_t Idx = 0; Idx < Size; Idx++) {
+ Printf("CLEANSE[%d]: Trying to replace byte %zd of %zd\n", NumAttempts,
+ Idx, Size);
+ uint8_t OriginalByte = U[Idx];
+ if (ReplacementBytes.end() != std::find(ReplacementBytes.begin(),
+ ReplacementBytes.end(),
+ OriginalByte))
+ continue;
+ for (auto NewByte : ReplacementBytes) {
+ U[Idx] = NewByte;
+ WriteToFile(U, TmpFilePath);
+ auto ExitCode = ExecuteCommand(Cmd);
+ RemoveFile(TmpFilePath);
+ if (!ExitCode) {
+ U[Idx] = OriginalByte;
+ } else {
+ Changed = true;
+ Printf("CLEANSE: Replaced byte %zd with 0x%x\n", Idx, NewByte);
+ WriteToFile(U, OutputFilePath);
+ break;
+ }
+ }
+ }
+ if (!Changed) break;
+ }
+ return 0;
+}
+
+int MinimizeCrashInput(const Vector<std::string> &Args,
+ const FuzzingOptions &Options) {
+ if (Inputs->size() != 1) {
+ Printf("ERROR: -minimize_crash should be given one input file\n");
+ return 1;
+ }
+ std::string InputFilePath = Inputs->at(0);
+ Command BaseCmd(Args);
+ BaseCmd.removeFlag("minimize_crash");
+ BaseCmd.removeFlag("exact_artifact_path");
+ assert(BaseCmd.hasArgument(InputFilePath));
+ BaseCmd.removeArgument(InputFilePath);
+ if (Flags.runs <= 0 && Flags.max_total_time == 0) {
+ Printf("INFO: you need to specify -runs=N or "
+ "-max_total_time=N with -minimize_crash=1\n"
+ "INFO: defaulting to -max_total_time=600\n");
+ BaseCmd.addFlag("max_total_time", "600");
+ }
+
+ BaseCmd.combineOutAndErr();
+
+ std::string CurrentFilePath = InputFilePath;
+ while (true) {
+ Unit U = FileToVector(CurrentFilePath);
+ Printf("CRASH_MIN: minimizing crash input: '%s' (%zd bytes)\n",
+ CurrentFilePath.c_str(), U.size());
+
+ Command Cmd(BaseCmd);
+ Cmd.addArgument(CurrentFilePath);
+
+ Printf("CRASH_MIN: executing: %s\n", Cmd.toString().c_str());
+ std::string CmdOutput;
+ bool Success = ExecuteCommand(Cmd, &CmdOutput);
+ if (Success) {
+ Printf("ERROR: the input %s did not crash\n", CurrentFilePath.c_str());
+ return 1;
+ }
+ Printf("CRASH_MIN: '%s' (%zd bytes) caused a crash. Will try to minimize "
+ "it further\n",
+ CurrentFilePath.c_str(), U.size());
+ auto DedupToken1 = GetDedupTokenFromCmdOutput(CmdOutput);
+ if (!DedupToken1.empty())
+ Printf("CRASH_MIN: DedupToken1: %s\n", DedupToken1.c_str());
+
+ std::string ArtifactPath =
+ Flags.exact_artifact_path
+ ? Flags.exact_artifact_path
+ : Options.ArtifactPrefix + "minimized-from-" + Hash(U);
+ Cmd.addFlag("minimize_crash_internal_step", "1");
+ Cmd.addFlag("exact_artifact_path", ArtifactPath);
+ Printf("CRASH_MIN: executing: %s\n", Cmd.toString().c_str());
+ CmdOutput.clear();
+ Success = ExecuteCommand(Cmd, &CmdOutput);
+ Printf("%s", CmdOutput.c_str());
+ if (Success) {
+ if (Flags.exact_artifact_path) {
+ CurrentFilePath = Flags.exact_artifact_path;
+ WriteToFile(U, CurrentFilePath);
+ }
+ Printf("CRASH_MIN: failed to minimize beyond %s (%d bytes), exiting\n",
+ CurrentFilePath.c_str(), U.size());
+ break;
+ }
+ auto DedupToken2 = GetDedupTokenFromCmdOutput(CmdOutput);
+ if (!DedupToken2.empty())
+ Printf("CRASH_MIN: DedupToken2: %s\n", DedupToken2.c_str());
+
+ if (DedupToken1 != DedupToken2) {
+ if (Flags.exact_artifact_path) {
+ CurrentFilePath = Flags.exact_artifact_path;
+ WriteToFile(U, CurrentFilePath);
+ }
+ Printf("CRASH_MIN: mismatch in dedup tokens"
+ " (looks like a different bug). Won't minimize further\n");
+ break;
+ }
+
+ CurrentFilePath = ArtifactPath;
+ Printf("*********************************\n");
+ }
+ return 0;
+}
+
+int MinimizeCrashInputInternalStep(Fuzzer *F, InputCorpus *Corpus) {
+ assert(Inputs->size() == 1);
+ std::string InputFilePath = Inputs->at(0);
+ Unit U = FileToVector(InputFilePath);
+ Printf("INFO: Starting MinimizeCrashInputInternalStep: %zd\n", U.size());
+ if (U.size() < 2) {
+ Printf("INFO: The input is small enough, exiting\n");
+ return 0;
+ }
+ F->SetMaxInputLen(U.size());
+ F->SetMaxMutationLen(U.size() - 1);
+ F->MinimizeCrashLoop(U);
+ Printf("INFO: Done MinimizeCrashInputInternalStep, no crashes found\n");
+ return 0;
+}
+
+int Merge(Fuzzer *F, FuzzingOptions &Options, const Vector<std::string> &Args,
+ const Vector<std::string> &Corpora, const char *CFPathOrNull) {
+ if (Corpora.size() < 2) {
+ Printf("INFO: Merge requires two or more corpus dirs\n");
+ return 0;
+ }
+
+ Vector<SizedFile> OldCorpus, NewCorpus;
+ int Res = GetSizedFilesFromDir(Corpora[0], &OldCorpus);
+ if (Res != 0)
+ return Res;
+ for (size_t i = 1; i < Corpora.size(); i++) {
+ Res = GetSizedFilesFromDir(Corpora[i], &NewCorpus);
+ if (Res != 0)
+ return Res;
+ }
+ std::sort(OldCorpus.begin(), OldCorpus.end());
+ std::sort(NewCorpus.begin(), NewCorpus.end());
+
+ std::string CFPath = CFPathOrNull ? CFPathOrNull : TempPath("Merge", ".txt");
+ Vector<std::string> NewFiles;
+ Set<uint32_t> NewFeatures, NewCov;
+ Res = CrashResistantMerge(Args, OldCorpus, NewCorpus, &NewFiles, {}, &NewFeatures,
+ {}, &NewCov, CFPath, true);
+ if (Res != 0)
+ return Res;
+
+ if (F->isGracefulExitRequested())
+ return 0;
+ for (auto &Path : NewFiles)
+ F->WriteToOutputCorpus(FileToVector(Path, Options.MaxLen));
+ // We are done, delete the control file if it was a temporary one.
+ if (!Flags.merge_control_file)
+ RemoveFile(CFPath);
+
+ return 0;
+}
+
+int AnalyzeDictionary(Fuzzer *F, const Vector<Unit>& Dict,
+ UnitVector& Corpus) {
+ Printf("Started dictionary minimization (up to %d tests)\n",
+ Dict.size() * Corpus.size() * 2);
+
+ // Scores and usage count for each dictionary unit.
+ Vector<int> Scores(Dict.size());
+ Vector<int> Usages(Dict.size());
+
+ Vector<size_t> InitialFeatures;
+ Vector<size_t> ModifiedFeatures;
+ for (auto &C : Corpus) {
+ // Get coverage for the testcase without modifications.
+ F->ExecuteCallback(C.data(), C.size());
+ InitialFeatures.clear();
+ TPC.CollectFeatures([&](size_t Feature) {
+ InitialFeatures.push_back(Feature);
+ });
+
+ for (size_t i = 0; i < Dict.size(); ++i) {
+ Vector<uint8_t> Data = C;
+ auto StartPos = std::search(Data.begin(), Data.end(),
+ Dict[i].begin(), Dict[i].end());
+ // Skip dictionary unit, if the testcase does not contain it.
+ if (StartPos == Data.end())
+ continue;
+
+ ++Usages[i];
+ while (StartPos != Data.end()) {
+ // Replace all occurrences of dictionary unit in the testcase.
+ auto EndPos = StartPos + Dict[i].size();
+ for (auto It = StartPos; It != EndPos; ++It)
+ *It ^= 0xFF;
+
+ StartPos = std::search(EndPos, Data.end(),
+ Dict[i].begin(), Dict[i].end());
+ }
+
+ // Get coverage for testcase with masked occurrences of dictionary unit.
+ F->ExecuteCallback(Data.data(), Data.size());
+ ModifiedFeatures.clear();
+ TPC.CollectFeatures([&](size_t Feature) {
+ ModifiedFeatures.push_back(Feature);
+ });
+
+ if (InitialFeatures == ModifiedFeatures)
+ --Scores[i];
+ else
+ Scores[i] += 2;
+ }
+ }
+
+ Printf("###### Useless dictionary elements. ######\n");
+ for (size_t i = 0; i < Dict.size(); ++i) {
+ // Dictionary units with positive score are treated as useful ones.
+ if (Scores[i] > 0)
+ continue;
+
+ Printf("\"");
+ PrintASCII(Dict[i].data(), Dict[i].size(), "\"");
+ Printf(" # Score: %d, Used: %d\n", Scores[i], Usages[i]);
+ }
+ Printf("###### End of useless dictionary elements. ######\n");
+ return 0;
+}
+
+int ParseSeedInuts(const char *seed_inputs, Vector<std::string> &Files) {
+ // Parse -seed_inputs=file1,file2,... or -seed_inputs=@seed_inputs_file
+ if (!seed_inputs) return 0;
+ std::string SeedInputs;
+ if (Flags.seed_inputs[0] == '@')
+ SeedInputs = FileToString(Flags.seed_inputs + 1); // File contains list.
+ else
+ SeedInputs = Flags.seed_inputs; // seed_inputs contains the list.
+ if (SeedInputs.empty()) {
+ Printf("seed_inputs is empty or @file does not exist.\n");
+ return 1;
+ }
+ // Parse SeedInputs.
+ size_t comma_pos = 0;
+ while ((comma_pos = SeedInputs.find_last_of(',')) != std::string::npos) {
+ Files.push_back(SeedInputs.substr(comma_pos + 1));
+ SeedInputs = SeedInputs.substr(0, comma_pos);
+ }
+ Files.push_back(SeedInputs);
+ return 0;
+}
+
+static Vector<SizedFile> ReadCorpora(const Vector<std::string> &CorpusDirs,
+ const Vector<std::string> &ExtraSeedFiles) {
+ Vector<SizedFile> SizedFiles;
+ size_t LastNumFiles = 0;
+ for (auto &Dir : CorpusDirs) {
+ GetSizedFilesFromDir(Dir, &SizedFiles);
+ Printf("INFO: % 8zd files found in %s\n", SizedFiles.size() - LastNumFiles,
+ Dir.c_str());
+ LastNumFiles = SizedFiles.size();
+ }
+ for (auto &File : ExtraSeedFiles)
+ if (auto Size = FileSize(File))
+ SizedFiles.push_back({File, Size});
+ return SizedFiles;
+}
+
+int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
+ using namespace fuzzer;
+ assert(argc && argv && "Argument pointers cannot be nullptr");
+ std::string Argv0((*argv)[0]);
+ if (!EF)
+ EF = new ExternalFunctions();
+ if (EF->LLVMFuzzerInitialize)
+ EF->LLVMFuzzerInitialize(argc, argv);
+ if (EF->__msan_scoped_disable_interceptor_checks)
+ EF->__msan_scoped_disable_interceptor_checks();
+ const Vector<std::string> Args(*argv, *argv + *argc);
+ assert(!Args.empty());
+ ProgName = new std::string(Args[0]);
+ if (Argv0 != *ProgName) {
+ Printf("ERROR: argv[0] has been modified in LLVMFuzzerInitialize\n");
+ return 1;
+ }
+ ParseFlags(Args, EF);
+ if (Flags.help) {
+ PrintHelp();
+ return 0;
+ }
+
+ if (Flags.close_fd_mask & 2)
+ DupAndCloseStderr();
+ if (Flags.close_fd_mask & 1)
+ CloseStdout();
+
+ if (Flags.jobs > 0 && Flags.workers == 0) {
+ Flags.workers = std::min(NumberOfCpuCores() / 2, Flags.jobs);
+ if (Flags.workers > 1)
+ Printf("Running %u workers\n", Flags.workers);
+ }
+
+ if (Flags.workers > 0 && Flags.jobs > 0)
+ return RunInMultipleProcesses(Args, Flags.workers, Flags.jobs);
+
+ FuzzingOptions Options;
+ Options.Verbosity = Flags.verbosity;
+ Options.MaxLen = Flags.max_len;
+ Options.LenControl = Flags.len_control;
+ Options.UnitTimeoutSec = Flags.timeout;
+ Options.ErrorExitCode = Flags.error_exitcode;
+ Options.TimeoutExitCode = Flags.timeout_exitcode;
+ Options.IgnoreTimeouts = Flags.ignore_timeouts;
+ Options.IgnoreOOMs = Flags.ignore_ooms;
+ Options.IgnoreCrashes = Flags.ignore_crashes;
+ Options.MaxTotalTimeSec = Flags.max_total_time;
+ Options.DoCrossOver = Flags.cross_over;
+ Options.MutateDepth = Flags.mutate_depth;
+ Options.ReduceDepth = Flags.reduce_depth;
+ Options.UseCounters = Flags.use_counters;
+ Options.UseMemmem = Flags.use_memmem;
+ Options.UseCmp = Flags.use_cmp;
+ Options.UseValueProfile = Flags.use_value_profile;
+ Options.Shrink = Flags.shrink;
+ Options.ReduceInputs = Flags.reduce_inputs;
+ Options.ShuffleAtStartUp = Flags.shuffle;
+ Options.PreferSmall = Flags.prefer_small;
+ Options.ReloadIntervalSec = Flags.reload;
+ Options.OnlyASCII = Flags.only_ascii;
+ Options.DetectLeaks = Flags.detect_leaks;
+ Options.PurgeAllocatorIntervalSec = Flags.purge_allocator_interval;
+ Options.TraceMalloc = Flags.trace_malloc;
+ Options.RssLimitMb = Flags.rss_limit_mb;
+ Options.MallocLimitMb = Flags.malloc_limit_mb;
+ if (!Options.MallocLimitMb)
+ Options.MallocLimitMb = Options.RssLimitMb;
+ if (Flags.runs >= 0)
+ Options.MaxNumberOfRuns = Flags.runs;
+ if (!Inputs->empty() && !Flags.minimize_crash_internal_step)
+ Options.OutputCorpus = (*Inputs)[0];
+ Options.ReportSlowUnits = Flags.report_slow_units;
+ if (Flags.artifact_prefix)
+ Options.ArtifactPrefix = Flags.artifact_prefix;
+ if (Flags.exact_artifact_path)
+ Options.ExactArtifactPath = Flags.exact_artifact_path;
+ Vector<Unit> Dictionary;
+ if (Flags.dict)
+ if (!ParseDictionaryFile(FileToString(Flags.dict), &Dictionary))
+ return 1;
+ if (Flags.verbosity > 0 && !Dictionary.empty())
+ Printf("Dictionary: %zd entries\n", Dictionary.size());
+ bool RunIndividualFiles = AllInputsAreFiles();
+ Options.SaveArtifacts =
+ !RunIndividualFiles || Flags.minimize_crash_internal_step;
+ Options.PrintNewCovPcs = Flags.print_pcs;
+ Options.PrintNewCovFuncs = Flags.print_funcs;
+ Options.PrintFinalStats = Flags.print_final_stats;
+ Options.PrintCorpusStats = Flags.print_corpus_stats;
+ Options.PrintCoverage = Flags.print_coverage;
+ if (Flags.exit_on_src_pos)
+ Options.ExitOnSrcPos = Flags.exit_on_src_pos;
+ if (Flags.exit_on_item)
+ Options.ExitOnItem = Flags.exit_on_item;
+ if (Flags.focus_function)
+ Options.FocusFunction = Flags.focus_function;
+ if (Flags.data_flow_trace)
+ Options.DataFlowTrace = Flags.data_flow_trace;
+ if (Flags.features_dir)
+ Options.FeaturesDir = Flags.features_dir;
+ if (Flags.collect_data_flow)
+ Options.CollectDataFlow = Flags.collect_data_flow;
+ if (Flags.stop_file)
+ Options.StopFile = Flags.stop_file;
+ Options.Entropic = Flags.entropic;
+ Options.EntropicFeatureFrequencyThreshold =
+ (size_t)Flags.entropic_feature_frequency_threshold;
+ Options.EntropicNumberOfRarestFeatures =
+ (size_t)Flags.entropic_number_of_rarest_features;
+ if (Options.Entropic) {
+ if (!Options.FocusFunction.empty()) {
+ Printf("ERROR: The parameters `--entropic` and `--focus_function` cannot "
+ "be used together.\n");
+ return 1;
+ }
+ Printf("INFO: Running with entropic power schedule (0x%X, %d).\n",
+ Options.EntropicFeatureFrequencyThreshold,
+ Options.EntropicNumberOfRarestFeatures);
+ }
+ struct EntropicOptions Entropic;
+ Entropic.Enabled = Options.Entropic;
+ Entropic.FeatureFrequencyThreshold =
+ Options.EntropicFeatureFrequencyThreshold;
+ Entropic.NumberOfRarestFeatures = Options.EntropicNumberOfRarestFeatures;
+
+ unsigned Seed = Flags.seed;
+ // Initialize Seed.
+ if (Seed == 0)
+ Seed =
+ std::chrono::system_clock::now().time_since_epoch().count() + GetPid();
+ if (Flags.verbosity)
+ Printf("INFO: Seed: %u\n", Seed);
+
+ if (Flags.collect_data_flow && !Flags.fork && !Flags.merge) {
+ if (RunIndividualFiles)
+ return CollectDataFlow(Flags.collect_data_flow, Flags.data_flow_trace,
+ ReadCorpora({}, *Inputs));
+ else
+ return CollectDataFlow(Flags.collect_data_flow, Flags.data_flow_trace,
+ ReadCorpora(*Inputs, {}));
+ }
+
+ Random Rand(Seed);
+ auto *MD = new MutationDispatcher(Rand, Options);
+ auto *Corpus = new InputCorpus(Options.OutputCorpus, Entropic);
+ auto *F = new Fuzzer(Callback, *Corpus, *MD, Options);
+
+ for (auto &U: Dictionary)
+ if (U.size() <= Word::GetMaxSize())
+ MD->AddWordToManualDictionary(Word(U.data(), U.size()));
+
+ // Threads are only supported by Chrome. Don't use them with emscripten
+ // for now.
+#if !LIBFUZZER_EMSCRIPTEN
+ StartRssThread(F, Flags.rss_limit_mb);
+#endif // LIBFUZZER_EMSCRIPTEN
+
+ Options.HandleAbrt = Flags.handle_abrt;
+ Options.HandleBus = Flags.handle_bus;
+ Options.HandleFpe = Flags.handle_fpe;
+ Options.HandleIll = Flags.handle_ill;
+ Options.HandleInt = Flags.handle_int;
+ Options.HandleSegv = Flags.handle_segv;
+ Options.HandleTerm = Flags.handle_term;
+ Options.HandleXfsz = Flags.handle_xfsz;
+ Options.HandleUsr1 = Flags.handle_usr1;
+ Options.HandleUsr2 = Flags.handle_usr2;
+ SetSignalHandler(Options);
+
+ std::atexit(Fuzzer::StaticExitCallback);
+
+ if (Flags.minimize_crash)
+ return MinimizeCrashInput(Args, Options);
+
+ if (Flags.minimize_crash_internal_step)
+ return MinimizeCrashInputInternalStep(F, Corpus);
+
+ if (Flags.cleanse_crash)
+ return CleanseCrashInput(Args, Options);
+
+ if (RunIndividualFiles) {
+ Options.SaveArtifacts = false;
+ int Runs = std::max(1, Flags.runs);
+ Printf("%s: Running %zd inputs %d time(s) each.\n", ProgName->c_str(),
+ Inputs->size(), Runs);
+ for (auto &Path : *Inputs) {
+ auto StartTime = system_clock::now();
+ Printf("Running: %s\n", Path.c_str());
+ for (int Iter = 0; Iter < Runs; Iter++)
+ RunOneTest(F, Path.c_str(), Options.MaxLen);
+ auto StopTime = system_clock::now();
+ auto MS = duration_cast<milliseconds>(StopTime - StartTime).count();
+ Printf("Executed %s in %zd ms\n", Path.c_str(), (long)MS);
+ }
+ Printf("***\n"
+ "*** NOTE: fuzzing was not performed, you have only\n"
+ "*** executed the target code on a fixed set of inputs.\n"
+ "***\n");
+ F->PrintFinalStats();
+ return 0;
+ }
+
+ if (Flags.fork)
+ return FuzzWithFork(F->GetMD().GetRand(), Options, Args, *Inputs, Flags.fork);
+
+ if (Flags.merge)
+ return Merge(F, Options, Args, *Inputs, Flags.merge_control_file);
+
+ if (Flags.merge_inner) {
+ const size_t kDefaultMaxMergeLen = 1 << 20;
+ if (Options.MaxLen == 0)
+ F->SetMaxInputLen(kDefaultMaxMergeLen);
+ assert(Flags.merge_control_file);
+ return F->CrashResistantMergeInternalStep(Flags.merge_control_file);
+ }
+
+ if (Flags.analyze_dict) {
+ size_t MaxLen = INT_MAX; // Large max length.
+ UnitVector InitialCorpus;
+ for (auto &Inp : *Inputs) {
+ Printf("Loading corpus dir: %s\n", Inp.c_str());
+ ReadDirToVectorOfUnits(Inp.c_str(), &InitialCorpus, nullptr,
+ MaxLen, /*ExitOnError=*/false);
+ }
+
+ if (Dictionary.empty() || Inputs->empty()) {
+ Printf("ERROR: can't analyze dict without dict and corpus provided\n");
+ return 1;
+ }
+ if (AnalyzeDictionary(F, Dictionary, InitialCorpus)) {
+ Printf("Dictionary analysis failed\n");
+ return 1;
+ }
+ Printf("Dictionary analysis succeeded\n");
+ return 0;
+ }
+
+ {
+ Vector<std::string> Files;
+ int Res = ParseSeedInuts(Flags.seed_inputs, Files);
+ if (Res != 0)
+ return Res;
+ auto CorporaFiles = ReadCorpora(*Inputs, Files);
+ Res = F->Loop(CorporaFiles);
+ if (Res != 0)
+ return Res;
+ if (F->isGracefulExitRequested())
+ return 0;
+ }
+
+ if (Flags.verbosity)
+ Printf("Done %zd runs in %zd second(s)\n", F->getTotalNumberOfRuns(),
+ F->secondsSinceProcessStartUp());
+ F->PrintFinalStats();
+
+ return 0; // Don't let F destroy itself.
+}
+
+extern "C" ATTRIBUTE_INTERFACE int
+LLVMFuzzerRunDriver(int *argc, char ***argv,
+ int (*UserCb)(const uint8_t *Data, size_t Size)) {
+ return FuzzerDriver(argc, argv, UserCb);
+}
+
+// Storage for global ExternalFunctions object.
+ExternalFunctions *EF = nullptr;
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerExtFunctions.def b/tools/fuzzing/libfuzzer/FuzzerExtFunctions.def
new file mode 100644
index 0000000000..51edf8444e
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerExtFunctions.def
@@ -0,0 +1,50 @@
+//===- FuzzerExtFunctions.def - External functions --------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// This defines the external function pointers that
+// ``fuzzer::ExternalFunctions`` should contain and try to initialize. The
+// EXT_FUNC macro must be defined at the point of inclusion. The signature of
+// the macro is:
+//
+// EXT_FUNC(<name>, <return_type>, <function_signature>, <warn_if_missing>)
+//===----------------------------------------------------------------------===//
+
+// Optional user functions
+EXT_FUNC(LLVMFuzzerInitialize, int, (int *argc, char ***argv), false);
+EXT_FUNC(LLVMFuzzerCustomMutator, size_t,
+ (uint8_t *Data, size_t Size, size_t MaxSize, unsigned int Seed),
+ false);
+EXT_FUNC(LLVMFuzzerCustomCrossOver, size_t,
+ (const uint8_t *Data1, size_t Size1,
+ const uint8_t *Data2, size_t Size2,
+ uint8_t *Out, size_t MaxOutSize, unsigned int Seed),
+ false);
+
+// Sanitizer functions
+EXT_FUNC(__lsan_enable, void, (), false);
+EXT_FUNC(__lsan_disable, void, (), false);
+EXT_FUNC(__lsan_do_recoverable_leak_check, int, (), false);
+EXT_FUNC(__sanitizer_acquire_crash_state, int, (), true);
+EXT_FUNC(__sanitizer_install_malloc_and_free_hooks, int,
+ (void (*malloc_hook)(const volatile void *, size_t),
+ void (*free_hook)(const volatile void *)),
+ false);
+EXT_FUNC(__sanitizer_log_write, void, (const char *buf, size_t len), false);
+EXT_FUNC(__sanitizer_purge_allocator, void, (), false);
+EXT_FUNC(__sanitizer_print_memory_profile, void, (size_t, size_t), false);
+EXT_FUNC(__sanitizer_print_stack_trace, void, (), true);
+EXT_FUNC(__sanitizer_symbolize_pc, void,
+ (void *, const char *fmt, char *out_buf, size_t out_buf_size), false);
+EXT_FUNC(__sanitizer_get_module_and_offset_for_pc, int,
+ (void *pc, char *module_path,
+ size_t module_path_len,void **pc_offset), false);
+EXT_FUNC(__sanitizer_set_death_callback, void, (void (*)(void)), true);
+EXT_FUNC(__sanitizer_set_report_fd, void, (void*), false);
+EXT_FUNC(__msan_scoped_disable_interceptor_checks, void, (), false);
+EXT_FUNC(__msan_scoped_enable_interceptor_checks, void, (), false);
+EXT_FUNC(__msan_unpoison, void, (const volatile void *, size_t size), false);
+EXT_FUNC(__msan_unpoison_param, void, (size_t n), false);
diff --git a/tools/fuzzing/libfuzzer/FuzzerExtFunctions.h b/tools/fuzzing/libfuzzer/FuzzerExtFunctions.h
new file mode 100644
index 0000000000..c88aac4e67
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerExtFunctions.h
@@ -0,0 +1,34 @@
+//===- FuzzerExtFunctions.h - Interface to external functions ---*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Defines an interface to (possibly optional) functions.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_EXT_FUNCTIONS_H
+#define LLVM_FUZZER_EXT_FUNCTIONS_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+namespace fuzzer {
+
+struct ExternalFunctions {
+ // Initialize function pointers. Functions that are not available will be set
+ // to nullptr. Do not call this constructor before ``main()`` has been
+ // entered.
+ ExternalFunctions();
+
+#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \
+ RETURN_TYPE(*NAME) FUNC_SIG = nullptr
+
+#include "FuzzerExtFunctions.def"
+
+#undef EXT_FUNC
+};
+} // namespace fuzzer
+
+#endif
diff --git a/tools/fuzzing/libfuzzer/FuzzerExtFunctionsDlsym.cpp b/tools/fuzzing/libfuzzer/FuzzerExtFunctionsDlsym.cpp
new file mode 100644
index 0000000000..95233d2a10
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerExtFunctionsDlsym.cpp
@@ -0,0 +1,51 @@
+//===- FuzzerExtFunctionsDlsym.cpp - Interface to external functions ------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Implementation for operating systems that support dlsym(). We only use it on
+// Apple platforms for now. We don't use this approach on Linux because it
+// requires that clients of LibFuzzer pass ``--export-dynamic`` to the linker.
+// That is a complication we don't wish to expose to clients right now.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_APPLE
+
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include <dlfcn.h>
+
+using namespace fuzzer;
+
+template <typename T>
+static T GetFnPtr(const char *FnName, bool WarnIfMissing) {
+ dlerror(); // Clear any previous errors.
+ void *Fn = dlsym(RTLD_DEFAULT, FnName);
+ if (Fn == nullptr) {
+ if (WarnIfMissing) {
+ const char *ErrorMsg = dlerror();
+ Printf("WARNING: Failed to find function \"%s\".", FnName);
+ if (ErrorMsg)
+ Printf(" Reason %s.", ErrorMsg);
+ Printf("\n");
+ }
+ }
+ return reinterpret_cast<T>(Fn);
+}
+
+namespace fuzzer {
+
+ExternalFunctions::ExternalFunctions() {
+#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \
+ this->NAME = GetFnPtr<decltype(ExternalFunctions::NAME)>(#NAME, WARN)
+
+#include "FuzzerExtFunctions.def"
+
+#undef EXT_FUNC
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_APPLE
diff --git a/tools/fuzzing/libfuzzer/FuzzerExtFunctionsWeak.cpp b/tools/fuzzing/libfuzzer/FuzzerExtFunctionsWeak.cpp
new file mode 100644
index 0000000000..24ddc57d47
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerExtFunctionsWeak.cpp
@@ -0,0 +1,54 @@
+//===- FuzzerExtFunctionsWeak.cpp - Interface to external functions -------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Implementation for Linux. This relies on the linker's support for weak
+// symbols. We don't use this approach on Apple platforms because it requires
+// clients of LibFuzzer to pass ``-U _<symbol_name>`` to the linker to allow
+// weak symbols to be undefined. That is a complication we don't want to expose
+// to clients right now.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FUCHSIA || \
+ LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD || LIBFUZZER_EMSCRIPTEN
+
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+
+extern "C" {
+// Declare these symbols as weak to allow them to be optionally defined.
+#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \
+ __attribute__((weak, visibility("default"))) RETURN_TYPE NAME FUNC_SIG
+
+#include "FuzzerExtFunctions.def"
+
+#undef EXT_FUNC
+}
+
+using namespace fuzzer;
+
+static void CheckFnPtr(void *FnPtr, const char *FnName, bool WarnIfMissing) {
+ if (FnPtr == nullptr && WarnIfMissing) {
+ Printf("WARNING: Failed to find function \"%s\".\n", FnName);
+ }
+}
+
+namespace fuzzer {
+
+ExternalFunctions::ExternalFunctions() {
+#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \
+ this->NAME = ::NAME; \
+ CheckFnPtr(reinterpret_cast<void *>(reinterpret_cast<uintptr_t>(::NAME)), \
+ #NAME, WARN);
+
+#include "FuzzerExtFunctions.def"
+
+#undef EXT_FUNC
+}
+
+} // namespace fuzzer
+
+#endif
diff --git a/tools/fuzzing/libfuzzer/FuzzerExtFunctionsWindows.cpp b/tools/fuzzing/libfuzzer/FuzzerExtFunctionsWindows.cpp
new file mode 100644
index 0000000000..688bad1d51
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerExtFunctionsWindows.cpp
@@ -0,0 +1,82 @@
+//=== FuzzerExtWindows.cpp - Interface to external functions --------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Implementation of FuzzerExtFunctions for Windows. Uses alternatename when
+// compiled with MSVC. Uses weak aliases when compiled with clang. Unfortunately
+// the method each compiler supports is not supported by the other.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_WINDOWS
+
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+
+using namespace fuzzer;
+
+// Intermediate macro to ensure the parameter is expanded before stringified.
+#define STRINGIFY_(A) #A
+#define STRINGIFY(A) STRINGIFY_(A)
+
+#if LIBFUZZER_MSVC
+// Copied from compiler-rt/lib/sanitizer_common/sanitizer_win_defs.h
+#if defined(_M_IX86) || defined(__i386__)
+#define WIN_SYM_PREFIX "_"
+#else
+#define WIN_SYM_PREFIX
+#endif
+
+// Declare external functions as having alternativenames, so that we can
+// determine if they are not defined.
+#define EXTERNAL_FUNC(Name, Default) \
+ __pragma(comment(linker, "/alternatename:" WIN_SYM_PREFIX STRINGIFY( \
+ Name) "=" WIN_SYM_PREFIX STRINGIFY(Default)))
+#else
+// Declare external functions as weak to allow them to default to a specified
+// function if not defined explicitly. We must use weak symbols because clang's
+// support for alternatename is not 100%, see
+// https://bugs.llvm.org/show_bug.cgi?id=40218 for more details.
+#define EXTERNAL_FUNC(Name, Default) \
+ __attribute__((weak, alias(STRINGIFY(Default))))
+#endif // LIBFUZZER_MSVC
+
+extern "C" {
+#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \
+ RETURN_TYPE NAME##Def FUNC_SIG { \
+ Printf("ERROR: Function \"%s\" not defined.\n", #NAME); \
+ exit(1); \
+ } \
+ EXTERNAL_FUNC(NAME, NAME##Def) RETURN_TYPE NAME FUNC_SIG
+
+#include "FuzzerExtFunctions.def"
+
+#undef EXT_FUNC
+}
+
+template <typename T>
+static T *GetFnPtr(T *Fun, T *FunDef, const char *FnName, bool WarnIfMissing) {
+ if (Fun == FunDef) {
+ if (WarnIfMissing)
+ Printf("WARNING: Failed to find function \"%s\".\n", FnName);
+ return nullptr;
+ }
+ return Fun;
+}
+
+namespace fuzzer {
+
+ExternalFunctions::ExternalFunctions() {
+#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \
+ this->NAME = GetFnPtr<decltype(::NAME)>(::NAME, ::NAME##Def, #NAME, WARN);
+
+#include "FuzzerExtFunctions.def"
+
+#undef EXT_FUNC
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_WINDOWS
diff --git a/tools/fuzzing/libfuzzer/FuzzerExtraCounters.cpp b/tools/fuzzing/libfuzzer/FuzzerExtraCounters.cpp
new file mode 100644
index 0000000000..d36beba1b1
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerExtraCounters.cpp
@@ -0,0 +1,42 @@
+//===- FuzzerExtraCounters.cpp - Extra coverage counters ------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Extra coverage counters defined by user code.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerPlatform.h"
+#include <cstdint>
+
+#if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FREEBSD || \
+ LIBFUZZER_OPENBSD || LIBFUZZER_FUCHSIA || LIBFUZZER_EMSCRIPTEN
+__attribute__((weak)) extern uint8_t __start___libfuzzer_extra_counters;
+__attribute__((weak)) extern uint8_t __stop___libfuzzer_extra_counters;
+
+namespace fuzzer {
+uint8_t *ExtraCountersBegin() { return &__start___libfuzzer_extra_counters; }
+uint8_t *ExtraCountersEnd() { return &__stop___libfuzzer_extra_counters; }
+ATTRIBUTE_NO_SANITIZE_ALL
+void ClearExtraCounters() { // hand-written memset, don't asan-ify.
+ uintptr_t *Beg = reinterpret_cast<uintptr_t*>(ExtraCountersBegin());
+ uintptr_t *End = reinterpret_cast<uintptr_t*>(ExtraCountersEnd());
+ for (; Beg < End; Beg++) {
+ *Beg = 0;
+ __asm__ __volatile__("" : : : "memory");
+ }
+}
+
+} // namespace fuzzer
+
+#else
+// TODO: implement for other platforms.
+namespace fuzzer {
+uint8_t *ExtraCountersBegin() { return nullptr; }
+uint8_t *ExtraCountersEnd() { return nullptr; }
+void ClearExtraCounters() {}
+} // namespace fuzzer
+
+#endif
diff --git a/tools/fuzzing/libfuzzer/FuzzerFlags.def b/tools/fuzzing/libfuzzer/FuzzerFlags.def
new file mode 100644
index 0000000000..832224a705
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerFlags.def
@@ -0,0 +1,169 @@
+//===- FuzzerFlags.def - Run-time flags -------------------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Flags. FUZZER_FLAG_INT/FUZZER_FLAG_STRING macros should be defined at the
+// point of inclusion. We are not using any flag parsing library for better
+// portability and independence.
+//===----------------------------------------------------------------------===//
+FUZZER_FLAG_INT(verbosity, 1, "Verbosity level.")
+FUZZER_FLAG_UNSIGNED(seed, 0, "Random seed. If 0, seed is generated.")
+FUZZER_FLAG_INT(runs, -1,
+ "Number of individual test runs (-1 for infinite runs).")
+FUZZER_FLAG_INT(max_len, 0, "Maximum length of the test input. "
+ "If 0, libFuzzer tries to guess a good value based on the corpus "
+ "and reports it. ")
+FUZZER_FLAG_INT(len_control, 100, "Try generating small inputs first, "
+ "then try larger inputs over time. Specifies the rate at which the length "
+ "limit is increased (smaller == faster). If 0, immediately try inputs with "
+ "size up to max_len. Default value is 0, if LLVMFuzzerCustomMutator is used.")
+FUZZER_FLAG_STRING(seed_inputs, "A comma-separated list of input files "
+ "to use as an additional seed corpus. Alternatively, an \"@\" followed by "
+ "the name of a file containing the comma-separated list.")
+FUZZER_FLAG_INT(cross_over, 1, "If 1, cross over inputs.")
+FUZZER_FLAG_INT(mutate_depth, 5,
+ "Apply this number of consecutive mutations to each input.")
+FUZZER_FLAG_INT(reduce_depth, 0, "Experimental/internal. "
+ "Reduce depth if mutations lose unique features")
+FUZZER_FLAG_INT(shuffle, 1, "Shuffle inputs at startup")
+FUZZER_FLAG_INT(prefer_small, 1,
+ "If 1, always prefer smaller inputs during the corpus shuffle.")
+FUZZER_FLAG_INT(
+ timeout, 1200,
+ "Timeout in seconds (if positive). "
+ "If one unit runs more than this number of seconds the process will abort.")
+FUZZER_FLAG_INT(error_exitcode, 77, "When libFuzzer itself reports a bug "
+ "this exit code will be used.")
+FUZZER_FLAG_INT(timeout_exitcode, 70, "When libFuzzer reports a timeout "
+ "this exit code will be used.")
+FUZZER_FLAG_INT(max_total_time, 0, "If positive, indicates the maximal total "
+ "time in seconds to run the fuzzer.")
+FUZZER_FLAG_INT(help, 0, "Print help.")
+FUZZER_FLAG_INT(fork, 0, "Experimental mode where fuzzing happens "
+ "in a subprocess")
+FUZZER_FLAG_INT(ignore_timeouts, 1, "Ignore timeouts in fork mode")
+FUZZER_FLAG_INT(ignore_ooms, 1, "Ignore OOMs in fork mode")
+FUZZER_FLAG_INT(ignore_crashes, 0, "Ignore crashes in fork mode")
+FUZZER_FLAG_INT(merge, 0, "If 1, the 2-nd, 3-rd, etc corpora will be "
+ "merged into the 1-st corpus. Only interesting units will be taken. "
+ "This flag can be used to minimize a corpus.")
+FUZZER_FLAG_STRING(stop_file, "Stop fuzzing ASAP if this file exists")
+FUZZER_FLAG_STRING(merge_inner, "internal flag")
+FUZZER_FLAG_STRING(merge_control_file,
+ "Specify a control file used for the merge process. "
+ "If a merge process gets killed it tries to leave this file "
+ "in a state suitable for resuming the merge. "
+ "By default a temporary file will be used."
+ "The same file can be used for multistep merge process.")
+FUZZER_FLAG_INT(minimize_crash, 0, "If 1, minimizes the provided"
+ " crash input. Use with -runs=N or -max_total_time=N to limit "
+ "the number attempts."
+ " Use with -exact_artifact_path to specify the output."
+ " Combine with ASAN_OPTIONS=dedup_token_length=3 (or similar) to ensure that"
+ " the minimized input triggers the same crash."
+ )
+FUZZER_FLAG_INT(cleanse_crash, 0, "If 1, tries to cleanse the provided"
+ " crash input to make it contain fewer original bytes."
+ " Use with -exact_artifact_path to specify the output."
+ )
+FUZZER_FLAG_INT(minimize_crash_internal_step, 0, "internal flag")
+FUZZER_FLAG_STRING(features_dir, "internal flag. Used to dump feature sets on disk."
+ "Every time a new input is added to the corpus, a corresponding file in the features_dir"
+ " is created containing the unique features of that input."
+ " Features are stored in binary format.")
+FUZZER_FLAG_INT(use_counters, 1, "Use coverage counters")
+FUZZER_FLAG_INT(use_memmem, 1,
+ "Use hints from intercepting memmem, strstr, etc")
+FUZZER_FLAG_INT(use_value_profile, 0,
+ "Experimental. Use value profile to guide fuzzing.")
+FUZZER_FLAG_INT(use_cmp, 1, "Use CMP traces to guide mutations")
+FUZZER_FLAG_INT(shrink, 0, "Experimental. Try to shrink corpus inputs.")
+FUZZER_FLAG_INT(reduce_inputs, 1,
+ "Try to reduce the size of inputs while preserving their full feature sets")
+FUZZER_FLAG_UNSIGNED(jobs, 0, "Number of jobs to run. If jobs >= 1 we spawn"
+ " this number of jobs in separate worker processes"
+ " with stdout/stderr redirected to fuzz-JOB.log.")
+FUZZER_FLAG_UNSIGNED(workers, 0,
+ "Number of simultaneous worker processes to run the jobs."
+ " If zero, \"min(jobs,NumberOfCpuCores()/2)\" is used.")
+FUZZER_FLAG_INT(reload, 1,
+ "Reload the main corpus every <N> seconds to get new units"
+ " discovered by other processes. If 0, disabled")
+FUZZER_FLAG_INT(report_slow_units, 10,
+ "Report slowest units if they run for more than this number of seconds.")
+FUZZER_FLAG_INT(only_ascii, 0,
+ "If 1, generate only ASCII (isprint+isspace) inputs.")
+FUZZER_FLAG_STRING(dict, "Experimental. Use the dictionary file.")
+FUZZER_FLAG_STRING(artifact_prefix, "Write fuzzing artifacts (crash, "
+ "timeout, or slow inputs) as "
+ "$(artifact_prefix)file")
+FUZZER_FLAG_STRING(exact_artifact_path,
+ "Write the single artifact on failure (crash, timeout) "
+ "as $(exact_artifact_path). This overrides -artifact_prefix "
+ "and will not use checksum in the file name. Do not "
+ "use the same path for several parallel processes.")
+FUZZER_FLAG_INT(print_pcs, 0, "If 1, print out newly covered PCs.")
+FUZZER_FLAG_INT(print_funcs, 2, "If >=1, print out at most this number of "
+ "newly covered functions.")
+FUZZER_FLAG_INT(print_final_stats, 0, "If 1, print statistics at exit.")
+FUZZER_FLAG_INT(print_corpus_stats, 0,
+ "If 1, print statistics on corpus elements at exit.")
+FUZZER_FLAG_INT(print_coverage, 0, "If 1, print coverage information as text"
+ " at exit.")
+FUZZER_FLAG_INT(dump_coverage, 0, "Deprecated.")
+FUZZER_FLAG_INT(handle_segv, 1, "If 1, try to intercept SIGSEGV.")
+FUZZER_FLAG_INT(handle_bus, 1, "If 1, try to intercept SIGBUS.")
+FUZZER_FLAG_INT(handle_abrt, 1, "If 1, try to intercept SIGABRT.")
+FUZZER_FLAG_INT(handle_ill, 1, "If 1, try to intercept SIGILL.")
+FUZZER_FLAG_INT(handle_fpe, 1, "If 1, try to intercept SIGFPE.")
+FUZZER_FLAG_INT(handle_int, 1, "If 1, try to intercept SIGINT.")
+FUZZER_FLAG_INT(handle_term, 1, "If 1, try to intercept SIGTERM.")
+FUZZER_FLAG_INT(handle_xfsz, 1, "If 1, try to intercept SIGXFSZ.")
+FUZZER_FLAG_INT(handle_usr1, 1, "If 1, try to intercept SIGUSR1.")
+FUZZER_FLAG_INT(handle_usr2, 1, "If 1, try to intercept SIGUSR2.")
+FUZZER_FLAG_INT(close_fd_mask, 0, "If 1, close stdout at startup; "
+ "if 2, close stderr; if 3, close both. "
+ "Be careful, this will also close e.g. stderr of asan.")
+FUZZER_FLAG_INT(detect_leaks, 1, "If 1, and if LeakSanitizer is enabled "
+ "try to detect memory leaks during fuzzing (i.e. not only at shut down).")
+FUZZER_FLAG_INT(purge_allocator_interval, 1, "Purge allocator caches and "
+ "quarantines every <N> seconds. When rss_limit_mb is specified (>0), "
+ "purging starts when RSS exceeds 50% of rss_limit_mb. Pass "
+ "purge_allocator_interval=-1 to disable this functionality.")
+FUZZER_FLAG_INT(trace_malloc, 0, "If >= 1 will print all mallocs/frees. "
+ "If >= 2 will also print stack traces.")
+FUZZER_FLAG_INT(rss_limit_mb, 2048, "If non-zero, the fuzzer will exit upon"
+ "reaching this limit of RSS memory usage.")
+FUZZER_FLAG_INT(malloc_limit_mb, 0, "If non-zero, the fuzzer will exit "
+ "if the target tries to allocate this number of Mb with one malloc call. "
+ "If zero (default) same limit as rss_limit_mb is applied.")
+FUZZER_FLAG_STRING(exit_on_src_pos, "Exit if a newly found PC originates"
+ " from the given source location. Example: -exit_on_src_pos=foo.cc:123. "
+ "Used primarily for testing libFuzzer itself.")
+FUZZER_FLAG_STRING(exit_on_item, "Exit if an item with a given sha1 sum"
+ " was added to the corpus. "
+ "Used primarily for testing libFuzzer itself.")
+FUZZER_FLAG_INT(ignore_remaining_args, 0, "If 1, ignore all arguments passed "
+ "after this one. Useful for fuzzers that need to do their own "
+ "argument parsing.")
+FUZZER_FLAG_STRING(focus_function, "Experimental. "
+ "Fuzzing will focus on inputs that trigger calls to this function. "
+ "If -focus_function=auto and -data_flow_trace is used, libFuzzer "
+ "will choose the focus functions automatically.")
+FUZZER_FLAG_INT(entropic, 0, "Experimental. Enables entropic power schedule.")
+FUZZER_FLAG_INT(entropic_feature_frequency_threshold, 0xFF, "Experimental. If "
+ "entropic is enabled, all features which are observed less often than "
+ "the specified value are considered as rare.")
+FUZZER_FLAG_INT(entropic_number_of_rarest_features, 100, "Experimental. If "
+ "entropic is enabled, we keep track of the frequencies only for the "
+ "Top-X least abundant features (union features that are considered as "
+ "rare).")
+
+FUZZER_FLAG_INT(analyze_dict, 0, "Experimental")
+FUZZER_DEPRECATED_FLAG(use_clang_coverage)
+FUZZER_FLAG_STRING(data_flow_trace, "Experimental: use the data flow trace")
+FUZZER_FLAG_STRING(collect_data_flow,
+ "Experimental: collect the data flow trace")
diff --git a/tools/fuzzing/libfuzzer/FuzzerFork.cpp b/tools/fuzzing/libfuzzer/FuzzerFork.cpp
new file mode 100644
index 0000000000..ee2a99a250
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerFork.cpp
@@ -0,0 +1,427 @@
+//===- FuzzerFork.cpp - run fuzzing in separate subprocesses --------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Spawn and orchestrate separate fuzzing processes.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerCommand.h"
+#include "FuzzerFork.h"
+#include "FuzzerIO.h"
+#include "FuzzerInternal.h"
+#include "FuzzerMerge.h"
+#include "FuzzerSHA1.h"
+#include "FuzzerTracePC.h"
+#include "FuzzerUtil.h"
+
+#include <atomic>
+#include <chrono>
+#include <condition_variable>
+#include <fstream>
+#include <memory>
+#include <mutex>
+#include <queue>
+#include <sstream>
+#include <thread>
+
+namespace fuzzer {
+
+struct Stats {
+ size_t number_of_executed_units = 0;
+ size_t peak_rss_mb = 0;
+ size_t average_exec_per_sec = 0;
+};
+
+static Stats ParseFinalStatsFromLog(const std::string &LogPath) {
+ std::ifstream In(LogPath);
+ std::string Line;
+ Stats Res;
+ struct {
+ const char *Name;
+ size_t *Var;
+ } NameVarPairs[] = {
+ {"stat::number_of_executed_units:", &Res.number_of_executed_units},
+ {"stat::peak_rss_mb:", &Res.peak_rss_mb},
+ {"stat::average_exec_per_sec:", &Res.average_exec_per_sec},
+ {nullptr, nullptr},
+ };
+ while (std::getline(In, Line, '\n')) {
+ if (Line.find("stat::") != 0) continue;
+ std::istringstream ISS(Line);
+ std::string Name;
+ size_t Val;
+ ISS >> Name >> Val;
+ for (size_t i = 0; NameVarPairs[i].Name; i++)
+ if (Name == NameVarPairs[i].Name)
+ *NameVarPairs[i].Var = Val;
+ }
+ return Res;
+}
+
+struct FuzzJob {
+ // Inputs.
+ Command Cmd;
+ std::string CorpusDir;
+ std::string FeaturesDir;
+ std::string LogPath;
+ std::string SeedListPath;
+ std::string CFPath;
+ size_t JobId;
+
+ int DftTimeInSeconds = 0;
+
+ // Fuzzing Outputs.
+ int ExitCode;
+
+ ~FuzzJob() {
+ RemoveFile(CFPath);
+ RemoveFile(LogPath);
+ RemoveFile(SeedListPath);
+ RmDirRecursive(CorpusDir);
+ RmDirRecursive(FeaturesDir);
+ }
+};
+
+struct GlobalEnv {
+ Vector<std::string> Args;
+ Vector<std::string> CorpusDirs;
+ std::string MainCorpusDir;
+ std::string TempDir;
+ std::string DFTDir;
+ std::string DataFlowBinary;
+ Set<uint32_t> Features, Cov;
+ Set<std::string> FilesWithDFT;
+ Vector<std::string> Files;
+ Random *Rand;
+ std::chrono::system_clock::time_point ProcessStartTime;
+ int Verbosity = 0;
+
+ size_t NumTimeouts = 0;
+ size_t NumOOMs = 0;
+ size_t NumCrashes = 0;
+
+
+ size_t NumRuns = 0;
+
+ std::string StopFile() { return DirPlusFile(TempDir, "STOP"); }
+
+ size_t secondsSinceProcessStartUp() const {
+ return std::chrono::duration_cast<std::chrono::seconds>(
+ std::chrono::system_clock::now() - ProcessStartTime)
+ .count();
+ }
+
+ FuzzJob *CreateNewJob(size_t JobId) {
+ Command Cmd(Args);
+ Cmd.removeFlag("fork");
+ Cmd.removeFlag("runs");
+ Cmd.removeFlag("collect_data_flow");
+ for (auto &C : CorpusDirs) // Remove all corpora from the args.
+ Cmd.removeArgument(C);
+ Cmd.addFlag("reload", "0"); // working in an isolated dir, no reload.
+ Cmd.addFlag("print_final_stats", "1");
+ Cmd.addFlag("print_funcs", "0"); // no need to spend time symbolizing.
+ Cmd.addFlag("max_total_time", std::to_string(std::min((size_t)300, JobId)));
+ Cmd.addFlag("stop_file", StopFile());
+ if (!DataFlowBinary.empty()) {
+ Cmd.addFlag("data_flow_trace", DFTDir);
+ if (!Cmd.hasFlag("focus_function"))
+ Cmd.addFlag("focus_function", "auto");
+ }
+ auto Job = new FuzzJob;
+ std::string Seeds;
+ if (size_t CorpusSubsetSize =
+ std::min(Files.size(), (size_t)sqrt(Files.size() + 2))) {
+ auto Time1 = std::chrono::system_clock::now();
+ for (size_t i = 0; i < CorpusSubsetSize; i++) {
+ auto &SF = Files[Rand->SkewTowardsLast(Files.size())];
+ Seeds += (Seeds.empty() ? "" : ",") + SF;
+ CollectDFT(SF);
+ }
+ auto Time2 = std::chrono::system_clock::now();
+ Job->DftTimeInSeconds = duration_cast<seconds>(Time2 - Time1).count();
+ }
+ if (!Seeds.empty()) {
+ Job->SeedListPath =
+ DirPlusFile(TempDir, std::to_string(JobId) + ".seeds");
+ WriteToFile(Seeds, Job->SeedListPath);
+ Cmd.addFlag("seed_inputs", "@" + Job->SeedListPath);
+ }
+ Job->LogPath = DirPlusFile(TempDir, std::to_string(JobId) + ".log");
+ Job->CorpusDir = DirPlusFile(TempDir, "C" + std::to_string(JobId));
+ Job->FeaturesDir = DirPlusFile(TempDir, "F" + std::to_string(JobId));
+ Job->CFPath = DirPlusFile(TempDir, std::to_string(JobId) + ".merge");
+ Job->JobId = JobId;
+
+
+ Cmd.addArgument(Job->CorpusDir);
+ Cmd.addFlag("features_dir", Job->FeaturesDir);
+
+ for (auto &D : {Job->CorpusDir, Job->FeaturesDir}) {
+ RmDirRecursive(D);
+ MkDir(D);
+ }
+
+ Cmd.setOutputFile(Job->LogPath);
+ Cmd.combineOutAndErr();
+
+ Job->Cmd = Cmd;
+
+ if (Verbosity >= 2)
+ Printf("Job %zd/%p Created: %s\n", JobId, Job,
+ Job->Cmd.toString().c_str());
+ // Start from very short runs and gradually increase them.
+ return Job;
+ }
+
+ int RunOneMergeJob(FuzzJob *Job) {
+ auto Stats = ParseFinalStatsFromLog(Job->LogPath);
+ NumRuns += Stats.number_of_executed_units;
+
+ Vector<SizedFile> TempFiles, MergeCandidates;
+ // Read all newly created inputs and their feature sets.
+ // Choose only those inputs that have new features.
+ int Res = GetSizedFilesFromDir(Job->CorpusDir, &TempFiles);
+ if (Res != 0)
+ return Res;
+ std::sort(TempFiles.begin(), TempFiles.end());
+ for (auto &F : TempFiles) {
+ auto FeatureFile = F.File;
+ FeatureFile.replace(0, Job->CorpusDir.size(), Job->FeaturesDir);
+ auto FeatureBytes = FileToVector(FeatureFile, 0, false);
+ assert((FeatureBytes.size() % sizeof(uint32_t)) == 0);
+ Vector<uint32_t> NewFeatures(FeatureBytes.size() / sizeof(uint32_t));
+ memcpy(NewFeatures.data(), FeatureBytes.data(), FeatureBytes.size());
+ for (auto Ft : NewFeatures) {
+ if (!Features.count(Ft)) {
+ MergeCandidates.push_back(F);
+ break;
+ }
+ }
+ }
+ // if (!FilesToAdd.empty() || Job->ExitCode != 0)
+ Printf("#%zd: cov: %zd ft: %zd corp: %zd exec/s %zd "
+ "oom/timeout/crash: %zd/%zd/%zd time: %zds job: %zd dft_time: %d\n",
+ NumRuns, Cov.size(), Features.size(), Files.size(),
+ Stats.average_exec_per_sec, NumOOMs, NumTimeouts, NumCrashes,
+ secondsSinceProcessStartUp(), Job->JobId, Job->DftTimeInSeconds);
+
+ if (MergeCandidates.empty()) return 0;
+
+ Vector<std::string> FilesToAdd;
+ Set<uint32_t> NewFeatures, NewCov;
+ CrashResistantMerge(Args, {}, MergeCandidates, &FilesToAdd, Features,
+ &NewFeatures, Cov, &NewCov, Job->CFPath, false);
+ if (Fuzzer::isGracefulExitRequested())
+ return 0;
+ for (auto &Path : FilesToAdd) {
+ auto U = FileToVector(Path);
+ auto NewPath = DirPlusFile(MainCorpusDir, Hash(U));
+ WriteToFile(U, NewPath);
+ Files.push_back(NewPath);
+ }
+ Features.insert(NewFeatures.begin(), NewFeatures.end());
+ Cov.insert(NewCov.begin(), NewCov.end());
+ for (auto Idx : NewCov)
+ if (auto *TE = TPC.PCTableEntryByIdx(Idx))
+ if (TPC.PcIsFuncEntry(TE))
+ PrintPC(" NEW_FUNC: %p %F %L\n", "",
+ TPC.GetNextInstructionPc(TE->PC));
+ return 0;
+ }
+
+
+ void CollectDFT(const std::string &InputPath) {
+ if (DataFlowBinary.empty()) return;
+ if (!FilesWithDFT.insert(InputPath).second) return;
+ Command Cmd(Args);
+ Cmd.removeFlag("fork");
+ Cmd.removeFlag("runs");
+ Cmd.addFlag("data_flow_trace", DFTDir);
+ Cmd.addArgument(InputPath);
+ for (auto &C : CorpusDirs) // Remove all corpora from the args.
+ Cmd.removeArgument(C);
+ Cmd.setOutputFile(DirPlusFile(TempDir, "dft.log"));
+ Cmd.combineOutAndErr();
+ // Printf("CollectDFT: %s\n", Cmd.toString().c_str());
+ ExecuteCommand(Cmd);
+ }
+
+};
+
+struct JobQueue {
+ std::queue<FuzzJob *> Qu;
+ std::mutex Mu;
+ std::condition_variable Cv;
+
+ void Push(FuzzJob *Job) {
+ {
+ std::lock_guard<std::mutex> Lock(Mu);
+ Qu.push(Job);
+ }
+ Cv.notify_one();
+ }
+ FuzzJob *Pop() {
+ std::unique_lock<std::mutex> Lk(Mu);
+ // std::lock_guard<std::mutex> Lock(Mu);
+ Cv.wait(Lk, [&]{return !Qu.empty();});
+ assert(!Qu.empty());
+ auto Job = Qu.front();
+ Qu.pop();
+ return Job;
+ }
+};
+
+void WorkerThread(JobQueue *FuzzQ, JobQueue *MergeQ) {
+ while (auto Job = FuzzQ->Pop()) {
+ // Printf("WorkerThread: job %p\n", Job);
+ Job->ExitCode = ExecuteCommand(Job->Cmd);
+ MergeQ->Push(Job);
+ }
+}
+
+// This is just a skeleton of an experimental -fork=1 feature.
+int FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ const Vector<std::string> &Args,
+ const Vector<std::string> &CorpusDirs, int NumJobs) {
+ Printf("INFO: -fork=%d: fuzzing in separate process(s)\n", NumJobs);
+
+ GlobalEnv Env;
+ Env.Args = Args;
+ Env.CorpusDirs = CorpusDirs;
+ Env.Rand = &Rand;
+ Env.Verbosity = Options.Verbosity;
+ Env.ProcessStartTime = std::chrono::system_clock::now();
+ Env.DataFlowBinary = Options.CollectDataFlow;
+
+ Vector<SizedFile> SeedFiles;
+ int Res;
+ for (auto &Dir : CorpusDirs) {
+ Res = GetSizedFilesFromDir(Dir, &SeedFiles);
+ if (Res != 0)
+ return Res;
+ }
+ std::sort(SeedFiles.begin(), SeedFiles.end());
+ Env.TempDir = TempPath("FuzzWithFork", ".dir");
+ Env.DFTDir = DirPlusFile(Env.TempDir, "DFT");
+ RmDirRecursive(Env.TempDir); // in case there is a leftover from old runs.
+ MkDir(Env.TempDir);
+ MkDir(Env.DFTDir);
+
+
+ if (CorpusDirs.empty())
+ MkDir(Env.MainCorpusDir = DirPlusFile(Env.TempDir, "C"));
+ else
+ Env.MainCorpusDir = CorpusDirs[0];
+
+ auto CFPath = DirPlusFile(Env.TempDir, "merge.txt");
+ Res = CrashResistantMerge(Env.Args, {}, SeedFiles, &Env.Files, {}, &Env.Features,
+ {}, &Env.Cov,
+ CFPath, false);
+ if (Res != 0)
+ return Res;
+ if (Fuzzer::isGracefulExitRequested())
+ return 0;
+
+ RemoveFile(CFPath);
+ Printf("INFO: -fork=%d: %zd seed inputs, starting to fuzz in %s\n", NumJobs,
+ Env.Files.size(), Env.TempDir.c_str());
+
+ int ExitCode = 0;
+
+ JobQueue FuzzQ, MergeQ;
+
+ auto StopJobs = [&]() {
+ for (int i = 0; i < NumJobs; i++)
+ FuzzQ.Push(nullptr);
+ MergeQ.Push(nullptr);
+ WriteToFile(Unit({1}), Env.StopFile());
+ };
+
+ size_t JobId = 1;
+ Vector<std::thread> Threads;
+ for (int t = 0; t < NumJobs; t++) {
+ Threads.push_back(std::thread(WorkerThread, &FuzzQ, &MergeQ));
+ FuzzQ.Push(Env.CreateNewJob(JobId++));
+ }
+
+ while (true) {
+ std::unique_ptr<FuzzJob> Job(MergeQ.Pop());
+ if (!Job)
+ break;
+ ExitCode = Job->ExitCode;
+ if (ExitCode == Options.InterruptExitCode) {
+ Printf("==%lu== libFuzzer: a child was interrupted; exiting\n", GetPid());
+ StopJobs();
+ break;
+ }
+ if (Fuzzer::MaybeExitGracefully())
+ return 0;
+
+ Res = Env.RunOneMergeJob(Job.get());
+ if (Res != 0)
+ return Res;
+ if (Fuzzer::isGracefulExitRequested())
+ return 0;
+
+ // Continue if our crash is one of the ignorred ones.
+ if (Options.IgnoreTimeouts && ExitCode == Options.TimeoutExitCode)
+ Env.NumTimeouts++;
+ else if (Options.IgnoreOOMs && ExitCode == Options.OOMExitCode)
+ Env.NumOOMs++;
+ else if (ExitCode != 0) {
+ Env.NumCrashes++;
+ if (Options.IgnoreCrashes) {
+ std::ifstream In(Job->LogPath);
+ std::string Line;
+ while (std::getline(In, Line, '\n'))
+ if (Line.find("ERROR:") != Line.npos ||
+ Line.find("runtime error:") != Line.npos)
+ Printf("%s\n", Line.c_str());
+ } else {
+ // And exit if we don't ignore this crash.
+ Printf("INFO: log from the inner process:\n%s",
+ FileToString(Job->LogPath).c_str());
+ StopJobs();
+ break;
+ }
+ }
+
+ // Stop if we are over the time budget.
+ // This is not precise, since other threads are still running
+ // and we will wait while joining them.
+ // We also don't stop instantly: other jobs need to finish.
+ if (Options.MaxTotalTimeSec > 0 &&
+ Env.secondsSinceProcessStartUp() >= (size_t)Options.MaxTotalTimeSec) {
+ Printf("INFO: fuzzed for %zd seconds, wrapping up soon\n",
+ Env.secondsSinceProcessStartUp());
+ StopJobs();
+ break;
+ }
+ if (Env.NumRuns >= Options.MaxNumberOfRuns) {
+ Printf("INFO: fuzzed for %zd iterations, wrapping up soon\n",
+ Env.NumRuns);
+ StopJobs();
+ break;
+ }
+
+ FuzzQ.Push(Env.CreateNewJob(JobId++));
+ }
+
+ for (auto &T : Threads)
+ T.join();
+
+ // The workers have terminated. Don't try to remove the directory before they
+ // terminate to avoid a race condition preventing cleanup on Windows.
+ RmDirRecursive(Env.TempDir);
+
+ // Use the exit code from the last child process.
+ Printf("INFO: exiting: %d time: %zds\n", ExitCode,
+ Env.secondsSinceProcessStartUp());
+ return ExitCode;
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerFork.h b/tools/fuzzing/libfuzzer/FuzzerFork.h
new file mode 100644
index 0000000000..1352171ad4
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerFork.h
@@ -0,0 +1,24 @@
+//===- FuzzerFork.h - run fuzzing in sub-processes --------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_FORK_H
+#define LLVM_FUZZER_FORK_H
+
+#include "FuzzerDefs.h"
+#include "FuzzerOptions.h"
+#include "FuzzerRandom.h"
+
+#include <string>
+
+namespace fuzzer {
+int FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ const Vector<std::string> &Args,
+ const Vector<std::string> &CorpusDirs, int NumJobs);
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_FORK_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerIO.cpp b/tools/fuzzing/libfuzzer/FuzzerIO.cpp
new file mode 100644
index 0000000000..6be2be67c6
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerIO.cpp
@@ -0,0 +1,165 @@
+//===- FuzzerIO.cpp - IO utils. -------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// IO functions.
+//===----------------------------------------------------------------------===//
+
+#include "mozilla/Unused.h"
+#include "FuzzerDefs.h"
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include "FuzzerUtil.h"
+#include <algorithm>
+#include <cstdarg>
+#include <fstream>
+#include <iterator>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+namespace fuzzer {
+
+static FILE *OutputFile = stderr;
+
+long GetEpoch(const std::string &Path) {
+ struct stat St;
+ if (stat(Path.c_str(), &St))
+ return 0; // Can't stat, be conservative.
+ return St.st_mtime;
+}
+
+Unit FileToVector(const std::string &Path, size_t MaxSize, bool ExitOnError) {
+ std::ifstream T(Path, std::ios::binary);
+ if (ExitOnError && !T) {
+ Printf("No such directory: %s; exiting\n", Path.c_str());
+ exit(1);
+ }
+
+ T.seekg(0, T.end);
+ auto EndPos = T.tellg();
+ if (EndPos < 0) return {};
+ size_t FileLen = EndPos;
+ if (MaxSize)
+ FileLen = std::min(FileLen, MaxSize);
+
+ T.seekg(0, T.beg);
+ Unit Res(FileLen);
+ T.read(reinterpret_cast<char *>(Res.data()), FileLen);
+ return Res;
+}
+
+std::string FileToString(const std::string &Path) {
+ std::ifstream T(Path, std::ios::binary);
+ return std::string((std::istreambuf_iterator<char>(T)),
+ std::istreambuf_iterator<char>());
+}
+
+void CopyFileToErr(const std::string &Path) {
+ Printf("%s", FileToString(Path).c_str());
+}
+
+void WriteToFile(const Unit &U, const std::string &Path) {
+ WriteToFile(U.data(), U.size(), Path);
+}
+
+void WriteToFile(const std::string &Data, const std::string &Path) {
+ WriteToFile(reinterpret_cast<const uint8_t *>(Data.c_str()), Data.size(),
+ Path);
+}
+
+void WriteToFile(const uint8_t *Data, size_t Size, const std::string &Path) {
+ // Use raw C interface because this function may be called from a sig handler.
+ FILE *Out = fopen(Path.c_str(), "wb");
+ if (!Out) return;
+ mozilla::Unused << fwrite(Data, sizeof(Data[0]), Size, Out);
+ fclose(Out);
+}
+
+void ReadDirToVectorOfUnits(const char *Path, Vector<Unit> *V,
+ long *Epoch, size_t MaxSize, bool ExitOnError) {
+ long E = Epoch ? *Epoch : 0;
+ Vector<std::string> Files;
+ int Res = ListFilesInDirRecursive(Path, Epoch, &Files, /*TopDir*/true);
+ if (ExitOnError && Res != 0)
+ exit(Res);
+ size_t NumLoaded = 0;
+ for (size_t i = 0; i < Files.size(); i++) {
+ auto &X = Files[i];
+ if (Epoch && GetEpoch(X) < E) continue;
+ NumLoaded++;
+ if ((NumLoaded & (NumLoaded - 1)) == 0 && NumLoaded >= 1024)
+ Printf("Loaded %zd/%zd files from %s\n", NumLoaded, Files.size(), Path);
+ auto S = FileToVector(X, MaxSize, ExitOnError);
+ if (!S.empty())
+ V->push_back(S);
+ }
+}
+
+
+int GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V) {
+ Vector<std::string> Files;
+ int Res = ListFilesInDirRecursive(Dir, 0, &Files, /*TopDir*/true);
+ if (Res != 0)
+ return Res;
+ for (auto &File : Files)
+ if (size_t Size = FileSize(File))
+ V->push_back({File, Size});
+ return 0;
+}
+
+std::string DirPlusFile(const std::string &DirPath,
+ const std::string &FileName) {
+ return DirPath + GetSeparator() + FileName;
+}
+
+void DupAndCloseStderr() {
+ int OutputFd = DuplicateFile(2);
+ if (OutputFd >= 0) {
+ FILE *NewOutputFile = OpenFile(OutputFd, "w");
+ if (NewOutputFile) {
+ OutputFile = NewOutputFile;
+ if (EF->__sanitizer_set_report_fd)
+ EF->__sanitizer_set_report_fd(
+ reinterpret_cast<void *>(GetHandleFromFd(OutputFd)));
+ DiscardOutput(2);
+ }
+ }
+}
+
+void CloseStdout() {
+ DiscardOutput(1);
+}
+
+void Printf(const char *Fmt, ...) {
+ va_list ap;
+ va_start(ap, Fmt);
+ vfprintf(OutputFile, Fmt, ap);
+ va_end(ap);
+ fflush(OutputFile);
+}
+
+void VPrintf(bool Verbose, const char *Fmt, ...) {
+ if (!Verbose) return;
+ va_list ap;
+ va_start(ap, Fmt);
+ vfprintf(OutputFile, Fmt, ap);
+ va_end(ap);
+ fflush(OutputFile);
+}
+
+void RmDirRecursive(const std::string &Dir) {
+ IterateDirRecursive(
+ Dir, [](const std::string &Path) {},
+ [](const std::string &Path) { RmDir(Path); },
+ [](const std::string &Path) { RemoveFile(Path); });
+}
+
+std::string TempPath(const char *Prefix, const char *Extension) {
+ return DirPlusFile(TmpDir(), std::string("libFuzzerTemp.") + Prefix +
+ std::to_string(GetPid()) + Extension);
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerIO.h b/tools/fuzzing/libfuzzer/FuzzerIO.h
new file mode 100644
index 0000000000..6c90ba6373
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerIO.h
@@ -0,0 +1,106 @@
+//===- FuzzerIO.h - Internal header for IO utils ----------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// IO interface.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_IO_H
+#define LLVM_FUZZER_IO_H
+
+#include "FuzzerDefs.h"
+
+namespace fuzzer {
+
+long GetEpoch(const std::string &Path);
+
+Unit FileToVector(const std::string &Path, size_t MaxSize = 0,
+ bool ExitOnError = true);
+
+std::string FileToString(const std::string &Path);
+
+void CopyFileToErr(const std::string &Path);
+
+void WriteToFile(const uint8_t *Data, size_t Size, const std::string &Path);
+// Write Data.c_str() to the file without terminating null character.
+void WriteToFile(const std::string &Data, const std::string &Path);
+void WriteToFile(const Unit &U, const std::string &Path);
+
+void ReadDirToVectorOfUnits(const char *Path, Vector<Unit> *V,
+ long *Epoch, size_t MaxSize, bool ExitOnError);
+
+// Returns "Dir/FileName" or equivalent for the current OS.
+std::string DirPlusFile(const std::string &DirPath,
+ const std::string &FileName);
+
+// Returns the name of the dir, similar to the 'dirname' utility.
+std::string DirName(const std::string &FileName);
+
+// Returns path to a TmpDir.
+std::string TmpDir();
+
+std::string TempPath(const char *Prefix, const char *Extension);
+
+bool IsInterestingCoverageFile(const std::string &FileName);
+
+void DupAndCloseStderr();
+
+void CloseStdout();
+
+void Printf(const char *Fmt, ...);
+void VPrintf(bool Verbose, const char *Fmt, ...);
+
+// Print using raw syscalls, useful when printing at early init stages.
+void RawPrint(const char *Str);
+
+// Platform specific functions:
+bool IsFile(const std::string &Path);
+size_t FileSize(const std::string &Path);
+
+int ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ Vector<std::string> *V, bool TopDir);
+
+void RmDirRecursive(const std::string &Dir);
+
+// Iterate files and dirs inside Dir, recursively.
+// Call DirPreCallback/DirPostCallback on dirs before/after
+// calling FileCallback on files.
+void IterateDirRecursive(const std::string &Dir,
+ void (*DirPreCallback)(const std::string &Dir),
+ void (*DirPostCallback)(const std::string &Dir),
+ void (*FileCallback)(const std::string &Dir));
+
+struct SizedFile {
+ std::string File;
+ size_t Size;
+ bool operator<(const SizedFile &B) const { return Size < B.Size; }
+};
+
+int GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V);
+
+char GetSeparator();
+// Similar to the basename utility: returns the file name w/o the dir prefix.
+std::string Basename(const std::string &Path);
+
+FILE* OpenFile(int Fd, const char *Mode);
+
+int CloseFile(int Fd);
+
+int DuplicateFile(int Fd);
+
+void RemoveFile(const std::string &Path);
+void RenameFile(const std::string &OldPath, const std::string &NewPath);
+
+intptr_t GetHandleFromFd(int fd);
+
+void MkDir(const std::string &Path);
+void RmDir(const std::string &Path);
+
+const std::string &getDevNull();
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_IO_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp b/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
new file mode 100644
index 0000000000..1a50295c01
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
@@ -0,0 +1,181 @@
+//===- FuzzerIOPosix.cpp - IO utils for Posix. ----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// IO functions implementation using Posix API.
+//===----------------------------------------------------------------------===//
+#include "mozilla/Unused.h"
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_POSIX || LIBFUZZER_FUCHSIA
+
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include <cstdarg>
+#include <cstdio>
+#include <dirent.h>
+#include <fstream>
+#include <iterator>
+#include <libgen.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+namespace fuzzer {
+
+bool IsFile(const std::string &Path) {
+ struct stat St;
+ if (stat(Path.c_str(), &St))
+ return false;
+ return S_ISREG(St.st_mode);
+}
+
+static bool IsDirectory(const std::string &Path) {
+ struct stat St;
+ if (stat(Path.c_str(), &St))
+ return false;
+ return S_ISDIR(St.st_mode);
+}
+
+size_t FileSize(const std::string &Path) {
+ struct stat St;
+ if (stat(Path.c_str(), &St))
+ return 0;
+ return St.st_size;
+}
+
+std::string Basename(const std::string &Path) {
+ size_t Pos = Path.rfind(GetSeparator());
+ if (Pos == std::string::npos) return Path;
+ assert(Pos < Path.size());
+ return Path.substr(Pos + 1);
+}
+
+int ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ Vector<std::string> *V, bool TopDir) {
+ auto E = GetEpoch(Dir);
+ if (Epoch)
+ if (E && *Epoch >= E) return 0;
+
+ DIR *D = opendir(Dir.c_str());
+ if (!D) {
+ Printf("%s: %s; exiting\n", strerror(errno), Dir.c_str());
+ return 1;
+ }
+ while (auto E = readdir(D)) {
+ std::string Path = DirPlusFile(Dir, E->d_name);
+ if (E->d_type == DT_REG || E->d_type == DT_LNK ||
+ (E->d_type == DT_UNKNOWN && IsFile(Path)))
+ V->push_back(Path);
+ else if ((E->d_type == DT_DIR ||
+ (E->d_type == DT_UNKNOWN && IsDirectory(Path))) &&
+ *E->d_name != '.') {
+ int Res = ListFilesInDirRecursive(Path, Epoch, V, false);
+ if (Res != 0)
+ return Res;
+ }
+ }
+ closedir(D);
+ if (Epoch && TopDir)
+ *Epoch = E;
+ return 0;
+}
+
+
+void IterateDirRecursive(const std::string &Dir,
+ void (*DirPreCallback)(const std::string &Dir),
+ void (*DirPostCallback)(const std::string &Dir),
+ void (*FileCallback)(const std::string &Dir)) {
+ DirPreCallback(Dir);
+ DIR *D = opendir(Dir.c_str());
+ if (!D) return;
+ while (auto E = readdir(D)) {
+ std::string Path = DirPlusFile(Dir, E->d_name);
+ if (E->d_type == DT_REG || E->d_type == DT_LNK ||
+ (E->d_type == DT_UNKNOWN && IsFile(Path)))
+ FileCallback(Path);
+ else if ((E->d_type == DT_DIR ||
+ (E->d_type == DT_UNKNOWN && IsDirectory(Path))) &&
+ *E->d_name != '.')
+ IterateDirRecursive(Path, DirPreCallback, DirPostCallback, FileCallback);
+ }
+ closedir(D);
+ DirPostCallback(Dir);
+}
+
+char GetSeparator() {
+ return '/';
+}
+
+FILE* OpenFile(int Fd, const char* Mode) {
+ return fdopen(Fd, Mode);
+}
+
+int CloseFile(int fd) {
+ return close(fd);
+}
+
+int DuplicateFile(int Fd) {
+ return dup(Fd);
+}
+
+void RemoveFile(const std::string &Path) {
+ unlink(Path.c_str());
+}
+
+void RenameFile(const std::string &OldPath, const std::string &NewPath) {
+ rename(OldPath.c_str(), NewPath.c_str());
+}
+
+intptr_t GetHandleFromFd(int fd) {
+ return static_cast<intptr_t>(fd);
+}
+
+std::string DirName(const std::string &FileName) {
+ char *Tmp = new char[FileName.size() + 1];
+ memcpy(Tmp, FileName.c_str(), FileName.size() + 1);
+ std::string Res = dirname(Tmp);
+ delete [] Tmp;
+ return Res;
+}
+
+std::string TmpDir() {
+ if (auto Env = getenv("TMPDIR"))
+ return Env;
+ return "/tmp";
+}
+
+bool IsInterestingCoverageFile(const std::string &FileName) {
+ if (FileName.find("compiler-rt/lib/") != std::string::npos)
+ return false; // sanitizer internal.
+ if (FileName.find("/usr/lib/") != std::string::npos)
+ return false;
+ if (FileName.find("/usr/include/") != std::string::npos)
+ return false;
+ if (FileName == "<null>")
+ return false;
+ return true;
+}
+
+void RawPrint(const char *Str) {
+ mozilla::Unused << write(2, Str, strlen(Str));
+}
+
+void MkDir(const std::string &Path) {
+ mkdir(Path.c_str(), 0700);
+}
+
+void RmDir(const std::string &Path) {
+ rmdir(Path.c_str());
+}
+
+const std::string &getDevNull() {
+ static const std::string devNull = "/dev/null";
+ return devNull;
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_POSIX
diff --git a/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp b/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp
new file mode 100644
index 0000000000..0e977bd025
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp
@@ -0,0 +1,417 @@
+//===- FuzzerIOWindows.cpp - IO utils for Windows. ------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// IO functions implementation for Windows.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_WINDOWS
+
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include <cstdarg>
+#include <cstdio>
+#include <fstream>
+#include <io.h>
+#include <iterator>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <windows.h>
+
+namespace fuzzer {
+
+static bool IsFile(const std::string &Path, const DWORD &FileAttributes) {
+
+ if (FileAttributes & FILE_ATTRIBUTE_NORMAL)
+ return true;
+
+ if (FileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+ return false;
+
+ HANDLE FileHandle(
+ CreateFileA(Path.c_str(), 0, FILE_SHARE_READ, NULL, OPEN_EXISTING,
+ FILE_FLAG_BACKUP_SEMANTICS, 0));
+
+ if (FileHandle == INVALID_HANDLE_VALUE) {
+ Printf("CreateFileA() failed for \"%s\" (Error code: %lu).\n", Path.c_str(),
+ GetLastError());
+ return false;
+ }
+
+ DWORD FileType = GetFileType(FileHandle);
+
+ if (FileType == FILE_TYPE_UNKNOWN) {
+ Printf("GetFileType() failed for \"%s\" (Error code: %lu).\n", Path.c_str(),
+ GetLastError());
+ CloseHandle(FileHandle);
+ return false;
+ }
+
+ if (FileType != FILE_TYPE_DISK) {
+ CloseHandle(FileHandle);
+ return false;
+ }
+
+ CloseHandle(FileHandle);
+ return true;
+}
+
+bool IsFile(const std::string &Path) {
+ DWORD Att = GetFileAttributesA(Path.c_str());
+
+ if (Att == INVALID_FILE_ATTRIBUTES) {
+ Printf("GetFileAttributesA() failed for \"%s\" (Error code: %lu).\n",
+ Path.c_str(), GetLastError());
+ return false;
+ }
+
+ return IsFile(Path, Att);
+}
+
+static bool IsDir(DWORD FileAttrs) {
+ if (FileAttrs == INVALID_FILE_ATTRIBUTES) return false;
+ return FileAttrs & FILE_ATTRIBUTE_DIRECTORY;
+}
+
+std::string Basename(const std::string &Path) {
+ size_t Pos = Path.find_last_of("/\\");
+ if (Pos == std::string::npos) return Path;
+ assert(Pos < Path.size());
+ return Path.substr(Pos + 1);
+}
+
+size_t FileSize(const std::string &Path) {
+ WIN32_FILE_ATTRIBUTE_DATA attr;
+ if (!GetFileAttributesExA(Path.c_str(), GetFileExInfoStandard, &attr)) {
+ DWORD LastError = GetLastError();
+ if (LastError != ERROR_FILE_NOT_FOUND)
+ Printf("GetFileAttributesExA() failed for \"%s\" (Error code: %lu).\n",
+ Path.c_str(), LastError);
+ return 0;
+ }
+ ULARGE_INTEGER size;
+ size.HighPart = attr.nFileSizeHigh;
+ size.LowPart = attr.nFileSizeLow;
+ return size.QuadPart;
+}
+
+int ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ Vector<std::string> *V, bool TopDir) {
+ int Res;
+ auto E = GetEpoch(Dir);
+ if (Epoch)
+ if (E && *Epoch >= E) return 0;
+
+ std::string Path(Dir);
+ assert(!Path.empty());
+ if (Path.back() != '\\')
+ Path.push_back('\\');
+ Path.push_back('*');
+
+ // Get the first directory entry.
+ WIN32_FIND_DATAA FindInfo;
+ HANDLE FindHandle(FindFirstFileA(Path.c_str(), &FindInfo));
+ if (FindHandle == INVALID_HANDLE_VALUE)
+ {
+ if (GetLastError() == ERROR_FILE_NOT_FOUND)
+ return 0;
+ Printf("No such file or directory: %s; exiting\n", Dir.c_str());
+ return 1;
+ }
+
+ do {
+ std::string FileName = DirPlusFile(Dir, FindInfo.cFileName);
+
+ if (FindInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
+ size_t FilenameLen = strlen(FindInfo.cFileName);
+ if ((FilenameLen == 1 && FindInfo.cFileName[0] == '.') ||
+ (FilenameLen == 2 && FindInfo.cFileName[0] == '.' &&
+ FindInfo.cFileName[1] == '.'))
+ continue;
+
+ int Res = ListFilesInDirRecursive(FileName, Epoch, V, false);
+ if (Res != 0)
+ return Res;
+ }
+ else if (IsFile(FileName, FindInfo.dwFileAttributes))
+ V->push_back(FileName);
+ } while (FindNextFileA(FindHandle, &FindInfo));
+
+ DWORD LastError = GetLastError();
+ if (LastError != ERROR_NO_MORE_FILES)
+ Printf("FindNextFileA failed (Error code: %lu).\n", LastError);
+
+ FindClose(FindHandle);
+
+ if (Epoch && TopDir)
+ *Epoch = E;
+ return 0;
+}
+
+
+void IterateDirRecursive(const std::string &Dir,
+ void (*DirPreCallback)(const std::string &Dir),
+ void (*DirPostCallback)(const std::string &Dir),
+ void (*FileCallback)(const std::string &Dir)) {
+ // TODO(metzman): Implement ListFilesInDirRecursive via this function.
+ DirPreCallback(Dir);
+
+ DWORD DirAttrs = GetFileAttributesA(Dir.c_str());
+ if (!IsDir(DirAttrs)) return;
+
+ std::string TargetDir(Dir);
+ assert(!TargetDir.empty());
+ if (TargetDir.back() != '\\') TargetDir.push_back('\\');
+ TargetDir.push_back('*');
+
+ WIN32_FIND_DATAA FindInfo;
+ // Find the directory's first file.
+ HANDLE FindHandle = FindFirstFileA(TargetDir.c_str(), &FindInfo);
+ if (FindHandle == INVALID_HANDLE_VALUE) {
+ DWORD LastError = GetLastError();
+ if (LastError != ERROR_FILE_NOT_FOUND) {
+ // If the directory isn't empty, then something abnormal is going on.
+ Printf("FindFirstFileA failed for %s (Error code: %lu).\n", Dir.c_str(),
+ LastError);
+ }
+ return;
+ }
+
+ do {
+ std::string Path = DirPlusFile(Dir, FindInfo.cFileName);
+ DWORD PathAttrs = FindInfo.dwFileAttributes;
+ if (IsDir(PathAttrs)) {
+ // Is Path the current directory (".") or the parent ("..")?
+ if (strcmp(FindInfo.cFileName, ".") == 0 ||
+ strcmp(FindInfo.cFileName, "..") == 0)
+ continue;
+ IterateDirRecursive(Path, DirPreCallback, DirPostCallback, FileCallback);
+ } else if (PathAttrs != INVALID_FILE_ATTRIBUTES) {
+ FileCallback(Path);
+ }
+ } while (FindNextFileA(FindHandle, &FindInfo));
+
+ DWORD LastError = GetLastError();
+ if (LastError != ERROR_NO_MORE_FILES)
+ Printf("FindNextFileA failed for %s (Error code: %lu).\n", Dir.c_str(),
+ LastError);
+
+ FindClose(FindHandle);
+ DirPostCallback(Dir);
+}
+
+char GetSeparator() {
+ return '\\';
+}
+
+FILE* OpenFile(int Fd, const char* Mode) {
+ return _fdopen(Fd, Mode);
+}
+
+int CloseFile(int Fd) {
+ return _close(Fd);
+}
+
+int DuplicateFile(int Fd) {
+ return _dup(Fd);
+}
+
+void RemoveFile(const std::string &Path) {
+ _unlink(Path.c_str());
+}
+
+void RenameFile(const std::string &OldPath, const std::string &NewPath) {
+ rename(OldPath.c_str(), NewPath.c_str());
+}
+
+intptr_t GetHandleFromFd(int fd) {
+ return _get_osfhandle(fd);
+}
+
+static bool IsSeparator(char C) {
+ return C == '\\' || C == '/';
+}
+
+// Parse disk designators, like "C:\". If Relative == true, also accepts: "C:".
+// Returns number of characters considered if successful.
+static size_t ParseDrive(const std::string &FileName, const size_t Offset,
+ bool Relative = true) {
+ if (Offset + 1 >= FileName.size() || FileName[Offset + 1] != ':')
+ return 0;
+ if (Offset + 2 >= FileName.size() || !IsSeparator(FileName[Offset + 2])) {
+ if (!Relative) // Accept relative path?
+ return 0;
+ else
+ return 2;
+ }
+ return 3;
+}
+
+// Parse a file name, like: SomeFile.txt
+// Returns number of characters considered if successful.
+static size_t ParseFileName(const std::string &FileName, const size_t Offset) {
+ size_t Pos = Offset;
+ const size_t End = FileName.size();
+ for(; Pos < End && !IsSeparator(FileName[Pos]); ++Pos)
+ ;
+ return Pos - Offset;
+}
+
+// Parse a directory ending in separator, like: `SomeDir\`
+// Returns number of characters considered if successful.
+static size_t ParseDir(const std::string &FileName, const size_t Offset) {
+ size_t Pos = Offset;
+ const size_t End = FileName.size();
+ if (Pos >= End || IsSeparator(FileName[Pos]))
+ return 0;
+ for(; Pos < End && !IsSeparator(FileName[Pos]); ++Pos)
+ ;
+ if (Pos >= End)
+ return 0;
+ ++Pos; // Include separator.
+ return Pos - Offset;
+}
+
+// Parse a servername and share, like: `SomeServer\SomeShare\`
+// Returns number of characters considered if successful.
+static size_t ParseServerAndShare(const std::string &FileName,
+ const size_t Offset) {
+ size_t Pos = Offset, Res;
+ if (!(Res = ParseDir(FileName, Pos)))
+ return 0;
+ Pos += Res;
+ if (!(Res = ParseDir(FileName, Pos)))
+ return 0;
+ Pos += Res;
+ return Pos - Offset;
+}
+
+// Parse the given Ref string from the position Offset, to exactly match the given
+// string Patt.
+// Returns number of characters considered if successful.
+static size_t ParseCustomString(const std::string &Ref, size_t Offset,
+ const char *Patt) {
+ size_t Len = strlen(Patt);
+ if (Offset + Len > Ref.size())
+ return 0;
+ return Ref.compare(Offset, Len, Patt) == 0 ? Len : 0;
+}
+
+// Parse a location, like:
+// \\?\UNC\Server\Share\ \\?\C:\ \\Server\Share\ \ C:\ C:
+// Returns number of characters considered if successful.
+static size_t ParseLocation(const std::string &FileName) {
+ size_t Pos = 0, Res;
+
+ if ((Res = ParseCustomString(FileName, Pos, R"(\\?\)"))) {
+ Pos += Res;
+ if ((Res = ParseCustomString(FileName, Pos, R"(UNC\)"))) {
+ Pos += Res;
+ if ((Res = ParseServerAndShare(FileName, Pos)))
+ return Pos + Res;
+ return 0;
+ }
+ if ((Res = ParseDrive(FileName, Pos, false)))
+ return Pos + Res;
+ return 0;
+ }
+
+ if (Pos < FileName.size() && IsSeparator(FileName[Pos])) {
+ ++Pos;
+ if (Pos < FileName.size() && IsSeparator(FileName[Pos])) {
+ ++Pos;
+ if ((Res = ParseServerAndShare(FileName, Pos)))
+ return Pos + Res;
+ return 0;
+ }
+ return Pos;
+ }
+
+ if ((Res = ParseDrive(FileName, Pos)))
+ return Pos + Res;
+
+ return Pos;
+}
+
+std::string DirName(const std::string &FileName) {
+ size_t LocationLen = ParseLocation(FileName);
+ size_t DirLen = 0, Res;
+ while ((Res = ParseDir(FileName, LocationLen + DirLen)))
+ DirLen += Res;
+ size_t FileLen = ParseFileName(FileName, LocationLen + DirLen);
+
+ if (LocationLen + DirLen + FileLen != FileName.size()) {
+ Printf("DirName() failed for \"%s\", invalid path.\n", FileName.c_str());
+ exit(1);
+ }
+
+ if (DirLen) {
+ --DirLen; // Remove trailing separator.
+ if (!FileLen) { // Path ended in separator.
+ assert(DirLen);
+ // Remove file name from Dir.
+ while (DirLen && !IsSeparator(FileName[LocationLen + DirLen - 1]))
+ --DirLen;
+ if (DirLen) // Remove trailing separator.
+ --DirLen;
+ }
+ }
+
+ if (!LocationLen) { // Relative path.
+ if (!DirLen)
+ return ".";
+ return std::string(".\\").append(FileName, 0, DirLen);
+ }
+
+ return FileName.substr(0, LocationLen + DirLen);
+}
+
+std::string TmpDir() {
+ std::string Tmp;
+ Tmp.resize(MAX_PATH + 1);
+ DWORD Size = GetTempPathA(Tmp.size(), &Tmp[0]);
+ if (Size == 0) {
+ Printf("Couldn't get Tmp path.\n");
+ exit(1);
+ }
+ Tmp.resize(Size);
+ return Tmp;
+}
+
+bool IsInterestingCoverageFile(const std::string &FileName) {
+ if (FileName.find("Program Files") != std::string::npos)
+ return false;
+ if (FileName.find("compiler-rt\\lib\\") != std::string::npos)
+ return false; // sanitizer internal.
+ if (FileName == "<null>")
+ return false;
+ return true;
+}
+
+void RawPrint(const char *Str) {
+ _write(2, Str, strlen(Str));
+}
+
+void MkDir(const std::string &Path) {
+ if (CreateDirectoryA(Path.c_str(), nullptr)) return;
+ Printf("CreateDirectoryA failed for %s (Error code: %lu).\n", Path.c_str(),
+ GetLastError());
+}
+
+void RmDir(const std::string &Path) {
+ if (RemoveDirectoryA(Path.c_str())) return;
+ Printf("RemoveDirectoryA failed for %s (Error code: %lu).\n", Path.c_str(),
+ GetLastError());
+}
+
+const std::string &getDevNull() {
+ static const std::string devNull = "NUL";
+ return devNull;
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_WINDOWS
diff --git a/tools/fuzzing/libfuzzer/FuzzerInterceptors.cpp b/tools/fuzzing/libfuzzer/FuzzerInterceptors.cpp
new file mode 100644
index 0000000000..a1a64780de
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerInterceptors.cpp
@@ -0,0 +1,235 @@
+//===-- FuzzerInterceptors.cpp --------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Intercept certain libc functions to aid fuzzing.
+// Linked only when other RTs that define their own interceptors are not linked.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerPlatform.h"
+
+#if LIBFUZZER_LINUX
+
+#define GET_CALLER_PC() __builtin_return_address(0)
+
+#define PTR_TO_REAL(x) real_##x
+#define REAL(x) __interception::PTR_TO_REAL(x)
+#define FUNC_TYPE(x) x##_type
+#define DEFINE_REAL(ret_type, func, ...) \
+ typedef ret_type (*FUNC_TYPE(func))(__VA_ARGS__); \
+ namespace __interception { \
+ FUNC_TYPE(func) PTR_TO_REAL(func); \
+ }
+
+#include <cassert>
+#include <cstdint>
+#include <dlfcn.h> // for dlsym()
+#include <sanitizer/common_interface_defs.h>
+
+static void *getFuncAddr(const char *name, uintptr_t wrapper_addr) {
+ void *addr = dlsym(RTLD_NEXT, name);
+ if (!addr) {
+ // If the lookup using RTLD_NEXT failed, the sanitizer runtime library is
+ // later in the library search order than the DSO that we are trying to
+ // intercept, which means that we cannot intercept this function. We still
+ // want the address of the real definition, though, so look it up using
+ // RTLD_DEFAULT.
+ addr = dlsym(RTLD_DEFAULT, name);
+
+ // In case `name' is not loaded, dlsym ends up finding the actual wrapper.
+ // We don't want to intercept the wrapper and have it point to itself.
+ if (reinterpret_cast<uintptr_t>(addr) == wrapper_addr)
+ addr = nullptr;
+ }
+ return addr;
+}
+
+static int FuzzerInited = 0;
+static bool FuzzerInitIsRunning;
+
+static void fuzzerInit();
+
+static void ensureFuzzerInited() {
+ assert(!FuzzerInitIsRunning);
+ if (!FuzzerInited) {
+ fuzzerInit();
+ }
+}
+
+static int internal_strcmp_strncmp(const char *s1, const char *s2, bool strncmp,
+ size_t n) {
+ size_t i = 0;
+ while (true) {
+ if (strncmp) {
+ if (i == n)
+ break;
+ i++;
+ }
+ unsigned c1 = *s1;
+ unsigned c2 = *s2;
+ if (c1 != c2)
+ return (c1 < c2) ? -1 : 1;
+ if (c1 == 0)
+ break;
+ s1++;
+ s2++;
+ }
+ return 0;
+}
+
+static int internal_strncmp(const char *s1, const char *s2, size_t n) {
+ return internal_strcmp_strncmp(s1, s2, true, n);
+}
+
+static int internal_strcmp(const char *s1, const char *s2) {
+ return internal_strcmp_strncmp(s1, s2, false, 0);
+}
+
+static int internal_memcmp(const void *s1, const void *s2, size_t n) {
+ const uint8_t *t1 = static_cast<const uint8_t *>(s1);
+ const uint8_t *t2 = static_cast<const uint8_t *>(s2);
+ for (size_t i = 0; i < n; ++i, ++t1, ++t2)
+ if (*t1 != *t2)
+ return *t1 < *t2 ? -1 : 1;
+ return 0;
+}
+
+static size_t internal_strlen(const char *s) {
+ size_t i = 0;
+ while (s[i])
+ i++;
+ return i;
+}
+
+static char *internal_strstr(const char *haystack, const char *needle) {
+ // This is O(N^2), but we are not using it in hot places.
+ size_t len1 = internal_strlen(haystack);
+ size_t len2 = internal_strlen(needle);
+ if (len1 < len2)
+ return nullptr;
+ for (size_t pos = 0; pos <= len1 - len2; pos++) {
+ if (internal_memcmp(haystack + pos, needle, len2) == 0)
+ return const_cast<char *>(haystack) + pos;
+ }
+ return nullptr;
+}
+
+extern "C" {
+
+DEFINE_REAL(int, bcmp, const void *, const void *, size_t)
+DEFINE_REAL(int, memcmp, const void *, const void *, size_t)
+DEFINE_REAL(int, strncmp, const char *, const char *, size_t)
+DEFINE_REAL(int, strcmp, const char *, const char *)
+DEFINE_REAL(int, strncasecmp, const char *, const char *, size_t)
+DEFINE_REAL(int, strcasecmp, const char *, const char *)
+DEFINE_REAL(char *, strstr, const char *, const char *)
+DEFINE_REAL(char *, strcasestr, const char *, const char *)
+DEFINE_REAL(void *, memmem, const void *, size_t, const void *, size_t)
+
+ATTRIBUTE_INTERFACE int bcmp(const char *s1, const char *s2, size_t n) {
+ if (!FuzzerInited)
+ return internal_memcmp(s1, s2, n);
+ int result = REAL(bcmp)(s1, s2, n);
+ __sanitizer_weak_hook_memcmp(GET_CALLER_PC(), s1, s2, n, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE int memcmp(const void *s1, const void *s2, size_t n) {
+ if (!FuzzerInited)
+ return internal_memcmp(s1, s2, n);
+ int result = REAL(memcmp)(s1, s2, n);
+ __sanitizer_weak_hook_memcmp(GET_CALLER_PC(), s1, s2, n, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE int strncmp(const char *s1, const char *s2, size_t n) {
+ if (!FuzzerInited)
+ return internal_strncmp(s1, s2, n);
+ int result = REAL(strncmp)(s1, s2, n);
+ __sanitizer_weak_hook_strncmp(GET_CALLER_PC(), s1, s2, n, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE int strcmp(const char *s1, const char *s2) {
+ if (!FuzzerInited)
+ return internal_strcmp(s1, s2);
+ int result = REAL(strcmp)(s1, s2);
+ __sanitizer_weak_hook_strcmp(GET_CALLER_PC(), s1, s2, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE int strncasecmp(const char *s1, const char *s2, size_t n) {
+ ensureFuzzerInited();
+ int result = REAL(strncasecmp)(s1, s2, n);
+ __sanitizer_weak_hook_strncasecmp(GET_CALLER_PC(), s1, s2, n, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE int strcasecmp(const char *s1, const char *s2) {
+ ensureFuzzerInited();
+ int result = REAL(strcasecmp)(s1, s2);
+ __sanitizer_weak_hook_strcasecmp(GET_CALLER_PC(), s1, s2, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE char *strstr(const char *s1, const char *s2) {
+ if (!FuzzerInited)
+ return internal_strstr(s1, s2);
+ char *result = REAL(strstr)(s1, s2);
+ __sanitizer_weak_hook_strstr(GET_CALLER_PC(), s1, s2, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE char *strcasestr(const char *s1, const char *s2) {
+ ensureFuzzerInited();
+ char *result = REAL(strcasestr)(s1, s2);
+ __sanitizer_weak_hook_strcasestr(GET_CALLER_PC(), s1, s2, result);
+ return result;
+}
+
+ATTRIBUTE_INTERFACE
+void *memmem(const void *s1, size_t len1, const void *s2, size_t len2) {
+ ensureFuzzerInited();
+ void *result = REAL(memmem)(s1, len1, s2, len2);
+ __sanitizer_weak_hook_memmem(GET_CALLER_PC(), s1, len1, s2, len2, result);
+ return result;
+}
+
+__attribute__((section(".preinit_array"),
+ used)) static void (*__local_fuzzer_preinit)(void) = fuzzerInit;
+
+} // extern "C"
+
+static void fuzzerInit() {
+ assert(!FuzzerInitIsRunning);
+ if (FuzzerInited)
+ return;
+ FuzzerInitIsRunning = true;
+
+ REAL(bcmp) = reinterpret_cast<memcmp_type>(
+ getFuncAddr("bcmp", reinterpret_cast<uintptr_t>(&bcmp)));
+ REAL(memcmp) = reinterpret_cast<memcmp_type>(
+ getFuncAddr("memcmp", reinterpret_cast<uintptr_t>(&memcmp)));
+ REAL(strncmp) = reinterpret_cast<strncmp_type>(
+ getFuncAddr("strncmp", reinterpret_cast<uintptr_t>(&strncmp)));
+ REAL(strcmp) = reinterpret_cast<strcmp_type>(
+ getFuncAddr("strcmp", reinterpret_cast<uintptr_t>(&strcmp)));
+ REAL(strncasecmp) = reinterpret_cast<strncasecmp_type>(
+ getFuncAddr("strncasecmp", reinterpret_cast<uintptr_t>(&strncasecmp)));
+ REAL(strcasecmp) = reinterpret_cast<strcasecmp_type>(
+ getFuncAddr("strcasecmp", reinterpret_cast<uintptr_t>(&strcasecmp)));
+ REAL(strstr) = reinterpret_cast<strstr_type>(
+ getFuncAddr("strstr", reinterpret_cast<uintptr_t>(&strstr)));
+ REAL(strcasestr) = reinterpret_cast<strcasestr_type>(
+ getFuncAddr("strcasestr", reinterpret_cast<uintptr_t>(&strcasestr)));
+ REAL(memmem) = reinterpret_cast<memmem_type>(
+ getFuncAddr("memmem", reinterpret_cast<uintptr_t>(&memmem)));
+
+ FuzzerInitIsRunning = false;
+ FuzzerInited = 1;
+}
+
+#endif
diff --git a/tools/fuzzing/libfuzzer/FuzzerInterface.h b/tools/fuzzing/libfuzzer/FuzzerInterface.h
new file mode 100644
index 0000000000..4f62822eac
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerInterface.h
@@ -0,0 +1,79 @@
+//===- FuzzerInterface.h - Interface header for the Fuzzer ------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Define the interface between libFuzzer and the library being tested.
+//===----------------------------------------------------------------------===//
+
+// NOTE: the libFuzzer interface is thin and in the majority of cases
+// you should not include this file into your target. In 95% of cases
+// all you need is to define the following function in your file:
+// extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);
+
+// WARNING: keep the interface in C.
+
+#ifndef LLVM_FUZZER_INTERFACE_H
+#define LLVM_FUZZER_INTERFACE_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+// Define FUZZER_INTERFACE_VISIBILITY to set default visibility in a way that
+// doesn't break MSVC.
+#if defined(_WIN32)
+#define FUZZER_INTERFACE_VISIBILITY __declspec(dllexport)
+#else
+#define FUZZER_INTERFACE_VISIBILITY __attribute__((visibility("default")))
+#endif
+
+// Mandatory user-provided target function.
+// Executes the code under test with [Data, Data+Size) as the input.
+// libFuzzer will invoke this function *many* times with different inputs.
+// Must return 0.
+FUZZER_INTERFACE_VISIBILITY int
+LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);
+
+// Optional user-provided initialization function.
+// If provided, this function will be called by libFuzzer once at startup.
+// It may read and modify argc/argv.
+// Must return 0.
+FUZZER_INTERFACE_VISIBILITY int LLVMFuzzerInitialize(int *argc, char ***argv);
+
+// Optional user-provided custom mutator.
+// Mutates raw data in [Data, Data+Size) inplace.
+// Returns the new size, which is not greater than MaxSize.
+// Given the same Seed produces the same mutation.
+FUZZER_INTERFACE_VISIBILITY size_t
+LLVMFuzzerCustomMutator(uint8_t *Data, size_t Size, size_t MaxSize,
+ unsigned int Seed);
+
+// Optional user-provided custom cross-over function.
+// Combines pieces of Data1 & Data2 together into Out.
+// Returns the new size, which is not greater than MaxOutSize.
+// Should produce the same mutation given the same Seed.
+FUZZER_INTERFACE_VISIBILITY size_t
+LLVMFuzzerCustomCrossOver(const uint8_t *Data1, size_t Size1,
+ const uint8_t *Data2, size_t Size2, uint8_t *Out,
+ size_t MaxOutSize, unsigned int Seed);
+
+// Experimental, may go away in future.
+// libFuzzer-provided function to be used inside LLVMFuzzerCustomMutator.
+// Mutates raw data in [Data, Data+Size) inplace.
+// Returns the new size, which is not greater than MaxSize.
+FUZZER_INTERFACE_VISIBILITY size_t
+LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize);
+
+#undef FUZZER_INTERFACE_VISIBILITY
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus
+
+#endif // LLVM_FUZZER_INTERFACE_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerInternal.h b/tools/fuzzing/libfuzzer/FuzzerInternal.h
new file mode 100644
index 0000000000..cc2650b58e
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerInternal.h
@@ -0,0 +1,175 @@
+//===- FuzzerInternal.h - Internal header for the Fuzzer --------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Define the main class fuzzer::Fuzzer and most functions.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_INTERNAL_H
+#define LLVM_FUZZER_INTERNAL_H
+
+#include "FuzzerDataFlowTrace.h"
+#include "FuzzerDefs.h"
+#include "FuzzerExtFunctions.h"
+#include "FuzzerInterface.h"
+#include "FuzzerOptions.h"
+#include "FuzzerSHA1.h"
+#include "FuzzerValueBitMap.h"
+#include <algorithm>
+#include <atomic>
+#include <chrono>
+#include <climits>
+#include <cstdlib>
+#include <string.h>
+
+namespace fuzzer {
+
+using namespace std::chrono;
+
+class Fuzzer {
+public:
+
+ Fuzzer(UserCallback CB, InputCorpus &Corpus, MutationDispatcher &MD,
+ FuzzingOptions Options);
+ ~Fuzzer();
+ int Loop(Vector<SizedFile> &CorporaFiles);
+ int ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles);
+ void MinimizeCrashLoop(const Unit &U);
+ void RereadOutputCorpus(size_t MaxSize);
+
+ size_t secondsSinceProcessStartUp() {
+ return duration_cast<seconds>(system_clock::now() - ProcessStartTime)
+ .count();
+ }
+
+ bool TimedOut() {
+ return Options.MaxTotalTimeSec > 0 &&
+ secondsSinceProcessStartUp() >
+ static_cast<size_t>(Options.MaxTotalTimeSec);
+ }
+
+ size_t execPerSec() {
+ size_t Seconds = secondsSinceProcessStartUp();
+ return Seconds ? TotalNumberOfRuns / Seconds : 0;
+ }
+
+ size_t getTotalNumberOfRuns() { return TotalNumberOfRuns; }
+
+ static void StaticAlarmCallback();
+ static void StaticCrashSignalCallback();
+ static void StaticExitCallback();
+ static void StaticInterruptCallback();
+ static void StaticFileSizeExceedCallback();
+ static void StaticGracefulExitCallback();
+
+ static void GracefullyExit();
+ static bool isGracefulExitRequested();
+
+ int ExecuteCallback(const uint8_t *Data, size_t Size);
+ bool RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile = false,
+ InputInfo *II = nullptr, bool *FoundUniqFeatures = nullptr);
+
+ // Merge Corpora[1:] into Corpora[0].
+ void Merge(const Vector<std::string> &Corpora);
+ int CrashResistantMergeInternalStep(const std::string &ControlFilePath);
+ MutationDispatcher &GetMD() { return MD; }
+ void PrintFinalStats();
+ void SetMaxInputLen(size_t MaxInputLen);
+ void SetMaxMutationLen(size_t MaxMutationLen);
+ void RssLimitCallback();
+
+ bool InFuzzingThread() const { return IsMyThread; }
+ size_t GetCurrentUnitInFuzzingThead(const uint8_t **Data) const;
+ void TryDetectingAMemoryLeak(const uint8_t *Data, size_t Size,
+ bool DuringInitialCorpusExecution);
+
+ void HandleMalloc(size_t Size);
+ static bool MaybeExitGracefully();
+ std::string WriteToOutputCorpus(const Unit &U);
+
+private:
+ void AlarmCallback();
+ void CrashCallback();
+ void ExitCallback();
+ void CrashOnOverwrittenData();
+ void InterruptCallback();
+ bool MutateAndTestOne();
+ void PurgeAllocator();
+ void ReportNewCoverage(InputInfo *II, const Unit &U);
+ void PrintPulseAndReportSlowInput(const uint8_t *Data, size_t Size);
+ void WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix);
+ void PrintStats(const char *Where, const char *End = "\n", size_t Units = 0,
+ size_t Features = 0);
+ void PrintStatusForNewUnit(const Unit &U, const char *Text);
+ void CheckExitOnSrcPosOrItem();
+
+ static void StaticDeathCallback();
+ void DumpCurrentUnit(const char *Prefix);
+ void DeathCallback();
+
+ void AllocateCurrentUnitData();
+ uint8_t *CurrentUnitData = nullptr;
+ std::atomic<size_t> CurrentUnitSize;
+ uint8_t BaseSha1[kSHA1NumBytes]; // Checksum of the base unit.
+
+ bool GracefulExitRequested = false;
+
+ size_t TotalNumberOfRuns = 0;
+ size_t NumberOfNewUnitsAdded = 0;
+
+ size_t LastCorpusUpdateRun = 0;
+
+ bool HasMoreMallocsThanFrees = false;
+ size_t NumberOfLeakDetectionAttempts = 0;
+
+ system_clock::time_point LastAllocatorPurgeAttemptTime = system_clock::now();
+
+ UserCallback CB;
+ InputCorpus &Corpus;
+ MutationDispatcher &MD;
+ FuzzingOptions Options;
+ DataFlowTrace DFT;
+
+ system_clock::time_point ProcessStartTime = system_clock::now();
+ system_clock::time_point UnitStartTime, UnitStopTime;
+ long TimeOfLongestUnitInSeconds = 0;
+ long EpochOfLastReadOfOutputCorpus = 0;
+
+ size_t MaxInputLen = 0;
+ size_t MaxMutationLen = 0;
+ size_t TmpMaxMutationLen = 0;
+
+ Vector<uint32_t> UniqFeatureSetTmp;
+
+ // Need to know our own thread.
+ static thread_local bool IsMyThread;
+};
+
+struct ScopedEnableMsanInterceptorChecks {
+ ScopedEnableMsanInterceptorChecks() {
+ if (EF->__msan_scoped_enable_interceptor_checks)
+ EF->__msan_scoped_enable_interceptor_checks();
+ }
+ ~ScopedEnableMsanInterceptorChecks() {
+ if (EF->__msan_scoped_disable_interceptor_checks)
+ EF->__msan_scoped_disable_interceptor_checks();
+ }
+};
+
+struct ScopedDisableMsanInterceptorChecks {
+ ScopedDisableMsanInterceptorChecks() {
+ if (EF->__msan_scoped_disable_interceptor_checks)
+ EF->__msan_scoped_disable_interceptor_checks();
+ }
+ ~ScopedDisableMsanInterceptorChecks() {
+ if (EF->__msan_scoped_enable_interceptor_checks)
+ EF->__msan_scoped_enable_interceptor_checks();
+ }
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_INTERNAL_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
new file mode 100644
index 0000000000..e7dfc187db
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
@@ -0,0 +1,901 @@
+//===- FuzzerLoop.cpp - Fuzzer's main loop --------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Fuzzer's main loop.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerCorpus.h"
+#include "FuzzerIO.h"
+#include "FuzzerInternal.h"
+#include "FuzzerMutate.h"
+#include "FuzzerPlatform.h"
+#include "FuzzerRandom.h"
+#include "FuzzerTracePC.h"
+#include <algorithm>
+#include <cstring>
+#include <memory>
+#include <mutex>
+#include <set>
+
+#if defined(__has_include)
+#if __has_include(<sanitizer / lsan_interface.h>)
+#include <sanitizer/lsan_interface.h>
+#endif
+#endif
+
+#define NO_SANITIZE_MEMORY
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#undef NO_SANITIZE_MEMORY
+#define NO_SANITIZE_MEMORY __attribute__((no_sanitize_memory))
+#endif
+#endif
+
+namespace fuzzer {
+static const size_t kMaxUnitSizeToPrint = 256;
+
+thread_local bool Fuzzer::IsMyThread;
+
+bool RunningUserCallback = false;
+
+// Only one Fuzzer per process.
+static Fuzzer *F;
+
+// Leak detection is expensive, so we first check if there were more mallocs
+// than frees (using the sanitizer malloc hooks) and only then try to call lsan.
+struct MallocFreeTracer {
+ void Start(int TraceLevel) {
+ this->TraceLevel = TraceLevel;
+ if (TraceLevel)
+ Printf("MallocFreeTracer: START\n");
+ Mallocs = 0;
+ Frees = 0;
+ }
+ // Returns true if there were more mallocs than frees.
+ bool Stop() {
+ if (TraceLevel)
+ Printf("MallocFreeTracer: STOP %zd %zd (%s)\n", Mallocs.load(),
+ Frees.load(), Mallocs == Frees ? "same" : "DIFFERENT");
+ bool Result = Mallocs > Frees;
+ Mallocs = 0;
+ Frees = 0;
+ TraceLevel = 0;
+ return Result;
+ }
+ std::atomic<size_t> Mallocs;
+ std::atomic<size_t> Frees;
+ int TraceLevel = 0;
+
+ std::recursive_mutex TraceMutex;
+ bool TraceDisabled = false;
+};
+
+static MallocFreeTracer AllocTracer;
+
+// Locks printing and avoids nested hooks triggered from mallocs/frees in
+// sanitizer.
+class TraceLock {
+public:
+ TraceLock() : Lock(AllocTracer.TraceMutex) {
+ AllocTracer.TraceDisabled = !AllocTracer.TraceDisabled;
+ }
+ ~TraceLock() { AllocTracer.TraceDisabled = !AllocTracer.TraceDisabled; }
+
+ bool IsDisabled() const {
+ // This is already inverted value.
+ return !AllocTracer.TraceDisabled;
+ }
+
+private:
+ std::lock_guard<std::recursive_mutex> Lock;
+};
+
+ATTRIBUTE_NO_SANITIZE_MEMORY
+void MallocHook(const volatile void *ptr, size_t size) {
+ size_t N = AllocTracer.Mallocs++;
+ F->HandleMalloc(size);
+ if (int TraceLevel = AllocTracer.TraceLevel) {
+ TraceLock Lock;
+ if (Lock.IsDisabled())
+ return;
+ Printf("MALLOC[%zd] %p %zd\n", N, ptr, size);
+ if (TraceLevel >= 2 && EF)
+ PrintStackTrace();
+ }
+}
+
+ATTRIBUTE_NO_SANITIZE_MEMORY
+void FreeHook(const volatile void *ptr) {
+ size_t N = AllocTracer.Frees++;
+ if (int TraceLevel = AllocTracer.TraceLevel) {
+ TraceLock Lock;
+ if (Lock.IsDisabled())
+ return;
+ Printf("FREE[%zd] %p\n", N, ptr);
+ if (TraceLevel >= 2 && EF)
+ PrintStackTrace();
+ }
+}
+
+// Crash on a single malloc that exceeds the rss limit.
+void Fuzzer::HandleMalloc(size_t Size) {
+ if (!Options.MallocLimitMb || (Size >> 20) < (size_t)Options.MallocLimitMb)
+ return;
+ Printf("==%d== ERROR: libFuzzer: out-of-memory (malloc(%zd))\n", GetPid(),
+ Size);
+ Printf(" To change the out-of-memory limit use -rss_limit_mb=<N>\n\n");
+ PrintStackTrace();
+ DumpCurrentUnit("oom-");
+ Printf("SUMMARY: libFuzzer: out-of-memory\n");
+ PrintFinalStats();
+ _Exit(Options.OOMExitCode); // Stop right now.
+}
+
+Fuzzer::Fuzzer(UserCallback CB, InputCorpus &Corpus, MutationDispatcher &MD,
+ FuzzingOptions Options)
+ : CB(CB), Corpus(Corpus), MD(MD), Options(Options) {
+ if (EF->__sanitizer_set_death_callback)
+ EF->__sanitizer_set_death_callback(StaticDeathCallback);
+ assert(!F);
+ F = this;
+ TPC.ResetMaps();
+ IsMyThread = true;
+ if (Options.DetectLeaks && EF->__sanitizer_install_malloc_and_free_hooks)
+ EF->__sanitizer_install_malloc_and_free_hooks(MallocHook, FreeHook);
+ TPC.SetUseCounters(Options.UseCounters);
+ TPC.SetUseValueProfileMask(Options.UseValueProfile);
+
+ if (Options.Verbosity)
+ TPC.PrintModuleInfo();
+ if (!Options.OutputCorpus.empty() && Options.ReloadIntervalSec)
+ EpochOfLastReadOfOutputCorpus = GetEpoch(Options.OutputCorpus);
+ MaxInputLen = MaxMutationLen = Options.MaxLen;
+ TmpMaxMutationLen = 0; // Will be set once we load the corpus.
+ AllocateCurrentUnitData();
+ CurrentUnitSize = 0;
+ memset(BaseSha1, 0, sizeof(BaseSha1));
+}
+
+Fuzzer::~Fuzzer() {}
+
+void Fuzzer::AllocateCurrentUnitData() {
+ if (CurrentUnitData || MaxInputLen == 0)
+ return;
+ CurrentUnitData = new uint8_t[MaxInputLen];
+}
+
+void Fuzzer::StaticDeathCallback() {
+ assert(F);
+ F->DeathCallback();
+}
+
+void Fuzzer::DumpCurrentUnit(const char *Prefix) {
+ if (!CurrentUnitData)
+ return; // Happens when running individual inputs.
+ ScopedDisableMsanInterceptorChecks S;
+ MD.PrintMutationSequence();
+ Printf("; base unit: %s\n", Sha1ToString(BaseSha1).c_str());
+ size_t UnitSize = CurrentUnitSize;
+ if (UnitSize <= kMaxUnitSizeToPrint) {
+ PrintHexArray(CurrentUnitData, UnitSize, "\n");
+ PrintASCII(CurrentUnitData, UnitSize, "\n");
+ }
+ WriteUnitToFileWithPrefix({CurrentUnitData, CurrentUnitData + UnitSize},
+ Prefix);
+}
+
+NO_SANITIZE_MEMORY
+void Fuzzer::DeathCallback() {
+ DumpCurrentUnit("crash-");
+ PrintFinalStats();
+}
+
+void Fuzzer::StaticAlarmCallback() {
+ assert(F);
+ F->AlarmCallback();
+}
+
+void Fuzzer::StaticCrashSignalCallback() {
+ assert(F);
+ F->CrashCallback();
+}
+
+void Fuzzer::StaticExitCallback() {
+ assert(F);
+ F->ExitCallback();
+}
+
+void Fuzzer::StaticInterruptCallback() {
+ assert(F);
+ F->InterruptCallback();
+}
+
+void Fuzzer::StaticGracefulExitCallback() {
+ assert(F);
+ F->GracefulExitRequested = true;
+ Printf("INFO: signal received, trying to exit gracefully\n");
+}
+
+void Fuzzer::StaticFileSizeExceedCallback() {
+ Printf("==%lu== ERROR: libFuzzer: file size exceeded\n", GetPid());
+ exit(1);
+}
+
+void Fuzzer::CrashCallback() {
+ if (EF->__sanitizer_acquire_crash_state &&
+ !EF->__sanitizer_acquire_crash_state())
+ return;
+ Printf("==%lu== ERROR: libFuzzer: deadly signal\n", GetPid());
+ PrintStackTrace();
+ Printf("NOTE: libFuzzer has rudimentary signal handlers.\n"
+ " Combine libFuzzer with AddressSanitizer or similar for better "
+ "crash reports.\n");
+ Printf("SUMMARY: libFuzzer: deadly signal\n");
+ DumpCurrentUnit("crash-");
+ PrintFinalStats();
+ _Exit(Options.ErrorExitCode); // Stop right now.
+}
+
+void Fuzzer::ExitCallback() {
+ if (!RunningUserCallback)
+ return; // This exit did not come from the user callback
+ if (EF->__sanitizer_acquire_crash_state &&
+ !EF->__sanitizer_acquire_crash_state())
+ return;
+ Printf("==%lu== ERROR: libFuzzer: fuzz target exited\n", GetPid());
+ PrintStackTrace();
+ Printf("SUMMARY: libFuzzer: fuzz target exited\n");
+ DumpCurrentUnit("crash-");
+ PrintFinalStats();
+ _Exit(Options.ErrorExitCode);
+}
+
+bool Fuzzer::MaybeExitGracefully() {
+ if (!F->GracefulExitRequested) return false;
+ Printf("==%lu== INFO: libFuzzer: exiting as requested\n", GetPid());
+ RmDirRecursive(TempPath("FuzzWithFork", ".dir"));
+ F->PrintFinalStats();
+ return true;
+}
+
+void Fuzzer::GracefullyExit() {
+ F->GracefulExitRequested = true;
+}
+
+bool Fuzzer::isGracefulExitRequested() {
+ return F->GracefulExitRequested;
+}
+
+void Fuzzer::InterruptCallback() {
+ Printf("==%lu== libFuzzer: run interrupted; exiting\n", GetPid());
+ PrintFinalStats();
+ ScopedDisableMsanInterceptorChecks S; // RmDirRecursive may call opendir().
+ RmDirRecursive(TempPath("FuzzWithFork", ".dir"));
+ // Stop right now, don't perform any at-exit actions.
+ _Exit(Options.InterruptExitCode);
+}
+
+NO_SANITIZE_MEMORY
+void Fuzzer::AlarmCallback() {
+ assert(Options.UnitTimeoutSec > 0);
+ // In Windows and Fuchsia, Alarm callback is executed by a different thread.
+ // NetBSD's current behavior needs this change too.
+#if !LIBFUZZER_WINDOWS && !LIBFUZZER_NETBSD && !LIBFUZZER_FUCHSIA
+ if (!InFuzzingThread())
+ return;
+#endif
+ if (!RunningUserCallback)
+ return; // We have not started running units yet.
+ size_t Seconds =
+ duration_cast<seconds>(system_clock::now() - UnitStartTime).count();
+ if (Seconds == 0)
+ return;
+ if (Options.Verbosity >= 2)
+ Printf("AlarmCallback %zd\n", Seconds);
+ if (Seconds >= (size_t)Options.UnitTimeoutSec) {
+ if (EF->__sanitizer_acquire_crash_state &&
+ !EF->__sanitizer_acquire_crash_state())
+ return;
+ Printf("ALARM: working on the last Unit for %zd seconds\n", Seconds);
+ Printf(" and the timeout value is %d (use -timeout=N to change)\n",
+ Options.UnitTimeoutSec);
+ DumpCurrentUnit("timeout-");
+ Printf("==%lu== ERROR: libFuzzer: timeout after %d seconds\n", GetPid(),
+ Seconds);
+ PrintStackTrace();
+ Printf("SUMMARY: libFuzzer: timeout\n");
+ PrintFinalStats();
+ _Exit(Options.TimeoutExitCode); // Stop right now.
+ }
+}
+
+void Fuzzer::RssLimitCallback() {
+ if (EF->__sanitizer_acquire_crash_state &&
+ !EF->__sanitizer_acquire_crash_state())
+ return;
+ Printf(
+ "==%lu== ERROR: libFuzzer: out-of-memory (used: %zdMb; limit: %zdMb)\n",
+ GetPid(), GetPeakRSSMb(), Options.RssLimitMb);
+ Printf(" To change the out-of-memory limit use -rss_limit_mb=<N>\n\n");
+ PrintMemoryProfile();
+ DumpCurrentUnit("oom-");
+ Printf("SUMMARY: libFuzzer: out-of-memory\n");
+ PrintFinalStats();
+ _Exit(Options.OOMExitCode); // Stop right now.
+}
+
+void Fuzzer::PrintStats(const char *Where, const char *End, size_t Units,
+ size_t Features) {
+ size_t ExecPerSec = execPerSec();
+ if (!Options.Verbosity)
+ return;
+ Printf("#%zd\t%s", TotalNumberOfRuns, Where);
+ if (size_t N = TPC.GetTotalPCCoverage())
+ Printf(" cov: %zd", N);
+ if (size_t N = Features ? Features : Corpus.NumFeatures())
+ Printf(" ft: %zd", N);
+ if (!Corpus.empty()) {
+ Printf(" corp: %zd", Corpus.NumActiveUnits());
+ if (size_t N = Corpus.SizeInBytes()) {
+ if (N < (1 << 14))
+ Printf("/%zdb", N);
+ else if (N < (1 << 24))
+ Printf("/%zdKb", N >> 10);
+ else
+ Printf("/%zdMb", N >> 20);
+ }
+ if (size_t FF = Corpus.NumInputsThatTouchFocusFunction())
+ Printf(" focus: %zd", FF);
+ }
+ if (TmpMaxMutationLen)
+ Printf(" lim: %zd", TmpMaxMutationLen);
+ if (Units)
+ Printf(" units: %zd", Units);
+
+ Printf(" exec/s: %zd", ExecPerSec);
+ Printf(" rss: %zdMb", GetPeakRSSMb());
+ Printf("%s", End);
+}
+
+void Fuzzer::PrintFinalStats() {
+ if (Options.PrintCoverage)
+ TPC.PrintCoverage();
+ if (Options.PrintCorpusStats)
+ Corpus.PrintStats();
+ if (!Options.PrintFinalStats)
+ return;
+ size_t ExecPerSec = execPerSec();
+ Printf("stat::number_of_executed_units: %zd\n", TotalNumberOfRuns);
+ Printf("stat::average_exec_per_sec: %zd\n", ExecPerSec);
+ Printf("stat::new_units_added: %zd\n", NumberOfNewUnitsAdded);
+ Printf("stat::slowest_unit_time_sec: %zd\n", TimeOfLongestUnitInSeconds);
+ Printf("stat::peak_rss_mb: %zd\n", GetPeakRSSMb());
+}
+
+void Fuzzer::SetMaxInputLen(size_t MaxInputLen) {
+ assert(this->MaxInputLen == 0); // Can only reset MaxInputLen from 0 to non-0.
+ assert(MaxInputLen);
+ this->MaxInputLen = MaxInputLen;
+ this->MaxMutationLen = MaxInputLen;
+ AllocateCurrentUnitData();
+ Printf("INFO: -max_len is not provided; "
+ "libFuzzer will not generate inputs larger than %zd bytes\n",
+ MaxInputLen);
+}
+
+void Fuzzer::SetMaxMutationLen(size_t MaxMutationLen) {
+ assert(MaxMutationLen && MaxMutationLen <= MaxInputLen);
+ this->MaxMutationLen = MaxMutationLen;
+}
+
+void Fuzzer::CheckExitOnSrcPosOrItem() {
+ if (!Options.ExitOnSrcPos.empty()) {
+ static auto *PCsSet = new Set<uintptr_t>;
+ auto HandlePC = [&](const TracePC::PCTableEntry *TE) {
+ if (!PCsSet->insert(TE->PC).second)
+ return;
+ std::string Descr = DescribePC("%F %L", TE->PC + 1);
+ if (Descr.find(Options.ExitOnSrcPos) != std::string::npos) {
+ Printf("INFO: found line matching '%s', exiting.\n",
+ Options.ExitOnSrcPos.c_str());
+ _Exit(0);
+ }
+ };
+ TPC.ForEachObservedPC(HandlePC);
+ }
+ if (!Options.ExitOnItem.empty()) {
+ if (Corpus.HasUnit(Options.ExitOnItem)) {
+ Printf("INFO: found item with checksum '%s', exiting.\n",
+ Options.ExitOnItem.c_str());
+ _Exit(0);
+ }
+ }
+}
+
+void Fuzzer::RereadOutputCorpus(size_t MaxSize) {
+ if (Options.OutputCorpus.empty() || !Options.ReloadIntervalSec)
+ return;
+ Vector<Unit> AdditionalCorpus;
+ ReadDirToVectorOfUnits(Options.OutputCorpus.c_str(), &AdditionalCorpus,
+ &EpochOfLastReadOfOutputCorpus, MaxSize,
+ /*ExitOnError*/ false);
+ if (Options.Verbosity >= 2)
+ Printf("Reload: read %zd new units.\n", AdditionalCorpus.size());
+ bool Reloaded = false;
+ for (auto &U : AdditionalCorpus) {
+ if (U.size() > MaxSize)
+ U.resize(MaxSize);
+ if (!Corpus.HasUnit(U)) {
+ if (RunOne(U.data(), U.size())) {
+ CheckExitOnSrcPosOrItem();
+ Reloaded = true;
+ }
+ }
+ }
+ if (Reloaded)
+ PrintStats("RELOAD");
+}
+
+void Fuzzer::PrintPulseAndReportSlowInput(const uint8_t *Data, size_t Size) {
+ auto TimeOfUnit =
+ duration_cast<seconds>(UnitStopTime - UnitStartTime).count();
+ if (!(TotalNumberOfRuns & (TotalNumberOfRuns - 1)) &&
+ secondsSinceProcessStartUp() >= 2)
+ PrintStats("pulse ");
+ if (TimeOfUnit > TimeOfLongestUnitInSeconds * 1.1 &&
+ TimeOfUnit >= Options.ReportSlowUnits) {
+ TimeOfLongestUnitInSeconds = TimeOfUnit;
+ Printf("Slowest unit: %zd s:\n", TimeOfLongestUnitInSeconds);
+ WriteUnitToFileWithPrefix({Data, Data + Size}, "slow-unit-");
+ }
+}
+
+static void WriteFeatureSetToFile(const std::string &FeaturesDir,
+ const std::string &FileName,
+ const Vector<uint32_t> &FeatureSet) {
+ if (FeaturesDir.empty() || FeatureSet.empty()) return;
+ WriteToFile(reinterpret_cast<const uint8_t *>(FeatureSet.data()),
+ FeatureSet.size() * sizeof(FeatureSet[0]),
+ DirPlusFile(FeaturesDir, FileName));
+}
+
+static void RenameFeatureSetFile(const std::string &FeaturesDir,
+ const std::string &OldFile,
+ const std::string &NewFile) {
+ if (FeaturesDir.empty()) return;
+ RenameFile(DirPlusFile(FeaturesDir, OldFile),
+ DirPlusFile(FeaturesDir, NewFile));
+}
+
+bool Fuzzer::RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile,
+ InputInfo *II, bool *FoundUniqFeatures) {
+ if (!Size)
+ return false;
+
+ if (ExecuteCallback(Data, Size) > 0) {
+ return false;
+ }
+
+ UniqFeatureSetTmp.clear();
+ size_t FoundUniqFeaturesOfII = 0;
+ size_t NumUpdatesBefore = Corpus.NumFeatureUpdates();
+ TPC.CollectFeatures([&](size_t Feature) {
+ if (Corpus.AddFeature(Feature, Size, Options.Shrink))
+ UniqFeatureSetTmp.push_back(Feature);
+ if (Options.Entropic)
+ Corpus.UpdateFeatureFrequency(II, Feature);
+ if (Options.ReduceInputs && II)
+ if (std::binary_search(II->UniqFeatureSet.begin(),
+ II->UniqFeatureSet.end(), Feature))
+ FoundUniqFeaturesOfII++;
+ });
+ if (FoundUniqFeatures)
+ *FoundUniqFeatures = FoundUniqFeaturesOfII;
+ PrintPulseAndReportSlowInput(Data, Size);
+ size_t NumNewFeatures = Corpus.NumFeatureUpdates() - NumUpdatesBefore;
+ if (NumNewFeatures) {
+ TPC.UpdateObservedPCs();
+ auto NewII = Corpus.AddToCorpus({Data, Data + Size}, NumNewFeatures,
+ MayDeleteFile, TPC.ObservedFocusFunction(),
+ UniqFeatureSetTmp, DFT, II);
+ WriteFeatureSetToFile(Options.FeaturesDir, Sha1ToString(NewII->Sha1),
+ NewII->UniqFeatureSet);
+ return true;
+ }
+ if (II && FoundUniqFeaturesOfII &&
+ II->DataFlowTraceForFocusFunction.empty() &&
+ FoundUniqFeaturesOfII == II->UniqFeatureSet.size() &&
+ II->U.size() > Size) {
+ auto OldFeaturesFile = Sha1ToString(II->Sha1);
+ Corpus.Replace(II, {Data, Data + Size});
+ RenameFeatureSetFile(Options.FeaturesDir, OldFeaturesFile,
+ Sha1ToString(II->Sha1));
+ return true;
+ }
+ return false;
+}
+
+size_t Fuzzer::GetCurrentUnitInFuzzingThead(const uint8_t **Data) const {
+ assert(InFuzzingThread());
+ *Data = CurrentUnitData;
+ return CurrentUnitSize;
+}
+
+void Fuzzer::CrashOnOverwrittenData() {
+ Printf("==%d== ERROR: libFuzzer: fuzz target overwrites its const input\n",
+ GetPid());
+ PrintStackTrace();
+ Printf("SUMMARY: libFuzzer: overwrites-const-input\n");
+ DumpCurrentUnit("crash-");
+ PrintFinalStats();
+ _Exit(Options.ErrorExitCode); // Stop right now.
+}
+
+// Compare two arrays, but not all bytes if the arrays are large.
+static bool LooseMemeq(const uint8_t *A, const uint8_t *B, size_t Size) {
+ const size_t Limit = 64;
+ if (Size <= 64)
+ return !memcmp(A, B, Size);
+ // Compare first and last Limit/2 bytes.
+ return !memcmp(A, B, Limit / 2) &&
+ !memcmp(A + Size - Limit / 2, B + Size - Limit / 2, Limit / 2);
+}
+
+int Fuzzer::ExecuteCallback(const uint8_t *Data, size_t Size) {
+ TPC.RecordInitialStack();
+ TotalNumberOfRuns++;
+ assert(InFuzzingThread());
+ // We copy the contents of Unit into a separate heap buffer
+ // so that we reliably find buffer overflows in it.
+ uint8_t *DataCopy = new uint8_t[Size];
+ memcpy(DataCopy, Data, Size);
+ if (EF->__msan_unpoison)
+ EF->__msan_unpoison(DataCopy, Size);
+ if (EF->__msan_unpoison_param)
+ EF->__msan_unpoison_param(2);
+ if (CurrentUnitData && CurrentUnitData != Data)
+ memcpy(CurrentUnitData, Data, Size);
+ CurrentUnitSize = Size;
+ int Res = 0;
+ {
+ ScopedEnableMsanInterceptorChecks S;
+ AllocTracer.Start(Options.TraceMalloc);
+ UnitStartTime = system_clock::now();
+ TPC.ResetMaps();
+ RunningUserCallback = true;
+ Res = CB(DataCopy, Size);
+ RunningUserCallback = false;
+ UnitStopTime = system_clock::now();
+ assert(Res >= 0);
+ HasMoreMallocsThanFrees = AllocTracer.Stop();
+ }
+ if (!LooseMemeq(DataCopy, Data, Size))
+ CrashOnOverwrittenData();
+ CurrentUnitSize = 0;
+ delete[] DataCopy;
+ return Res;
+}
+
+std::string Fuzzer::WriteToOutputCorpus(const Unit &U) {
+ if (Options.OnlyASCII)
+ assert(IsASCII(U));
+ if (Options.OutputCorpus.empty())
+ return "";
+ std::string Path = DirPlusFile(Options.OutputCorpus, Hash(U));
+ WriteToFile(U, Path);
+ if (Options.Verbosity >= 2)
+ Printf("Written %zd bytes to %s\n", U.size(), Path.c_str());
+ return Path;
+}
+
+void Fuzzer::WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix) {
+ if (!Options.SaveArtifacts)
+ return;
+ std::string Path = Options.ArtifactPrefix + Prefix + Hash(U);
+ if (!Options.ExactArtifactPath.empty())
+ Path = Options.ExactArtifactPath; // Overrides ArtifactPrefix.
+ WriteToFile(U, Path);
+ Printf("artifact_prefix='%s'; Test unit written to %s\n",
+ Options.ArtifactPrefix.c_str(), Path.c_str());
+ if (U.size() <= kMaxUnitSizeToPrint)
+ Printf("Base64: %s\n", Base64(U).c_str());
+}
+
+void Fuzzer::PrintStatusForNewUnit(const Unit &U, const char *Text) {
+ if (!Options.PrintNEW)
+ return;
+ PrintStats(Text, "");
+ if (Options.Verbosity) {
+ Printf(" L: %zd/%zd ", U.size(), Corpus.MaxInputSize());
+ MD.PrintMutationSequence();
+ Printf("\n");
+ }
+}
+
+void Fuzzer::ReportNewCoverage(InputInfo *II, const Unit &U) {
+ II->NumSuccessfullMutations++;
+ MD.RecordSuccessfulMutationSequence();
+ PrintStatusForNewUnit(U, II->Reduced ? "REDUCE" : "NEW ");
+ WriteToOutputCorpus(U);
+ NumberOfNewUnitsAdded++;
+ CheckExitOnSrcPosOrItem(); // Check only after the unit is saved to corpus.
+ LastCorpusUpdateRun = TotalNumberOfRuns;
+}
+
+// Tries detecting a memory leak on the particular input that we have just
+// executed before calling this function.
+void Fuzzer::TryDetectingAMemoryLeak(const uint8_t *Data, size_t Size,
+ bool DuringInitialCorpusExecution) {
+ if (!HasMoreMallocsThanFrees)
+ return; // mallocs==frees, a leak is unlikely.
+ if (!Options.DetectLeaks)
+ return;
+ if (!DuringInitialCorpusExecution &&
+ TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+ return;
+ if (!&(EF->__lsan_enable) || !&(EF->__lsan_disable) ||
+ !(EF->__lsan_do_recoverable_leak_check))
+ return; // No lsan.
+ // Run the target once again, but with lsan disabled so that if there is
+ // a real leak we do not report it twice.
+ EF->__lsan_disable();
+ ExecuteCallback(Data, Size);
+ EF->__lsan_enable();
+ if (!HasMoreMallocsThanFrees)
+ return; // a leak is unlikely.
+ if (NumberOfLeakDetectionAttempts++ > 1000) {
+ Options.DetectLeaks = false;
+ Printf("INFO: libFuzzer disabled leak detection after every mutation.\n"
+ " Most likely the target function accumulates allocated\n"
+ " memory in a global state w/o actually leaking it.\n"
+ " You may try running this binary with -trace_malloc=[12]"
+ " to get a trace of mallocs and frees.\n"
+ " If LeakSanitizer is enabled in this process it will still\n"
+ " run on the process shutdown.\n");
+ return;
+ }
+ // Now perform the actual lsan pass. This is expensive and we must ensure
+ // we don't call it too often.
+ if (EF->__lsan_do_recoverable_leak_check()) { // Leak is found, report it.
+ if (DuringInitialCorpusExecution)
+ Printf("\nINFO: a leak has been found in the initial corpus.\n\n");
+ Printf("INFO: to ignore leaks on libFuzzer side use -detect_leaks=0.\n\n");
+ CurrentUnitSize = Size;
+ DumpCurrentUnit("leak-");
+ PrintFinalStats();
+ _Exit(Options.ErrorExitCode); // not exit() to disable lsan further on.
+ }
+}
+
+bool Fuzzer::MutateAndTestOne() {
+ MD.StartMutationSequence();
+
+ auto &II = Corpus.ChooseUnitToMutate(MD.GetRand());
+ if (Options.DoCrossOver)
+ MD.SetCrossOverWith(&Corpus.ChooseUnitToMutate(MD.GetRand()).U);
+ const auto &U = II.U;
+ memcpy(BaseSha1, II.Sha1, sizeof(BaseSha1));
+ assert(CurrentUnitData);
+ size_t Size = U.size();
+ assert(Size <= MaxInputLen && "Oversized Unit");
+ memcpy(CurrentUnitData, U.data(), Size);
+
+ assert(MaxMutationLen > 0);
+
+ size_t CurrentMaxMutationLen =
+ Min(MaxMutationLen, Max(U.size(), TmpMaxMutationLen));
+ assert(CurrentMaxMutationLen > 0);
+
+ for (int i = 0; i < Options.MutateDepth; i++) {
+ if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+ break;
+ if (MaybeExitGracefully()) return true;
+ size_t NewSize = 0;
+ if (II.HasFocusFunction && !II.DataFlowTraceForFocusFunction.empty() &&
+ Size <= CurrentMaxMutationLen)
+ NewSize = MD.MutateWithMask(CurrentUnitData, Size, Size,
+ II.DataFlowTraceForFocusFunction);
+
+ // If MutateWithMask either failed or wasn't called, call default Mutate.
+ if (!NewSize)
+ NewSize = MD.Mutate(CurrentUnitData, Size, CurrentMaxMutationLen);
+
+ if (!NewSize)
+ continue;
+
+ assert(NewSize > 0 && "Mutator returned empty unit");
+ assert(NewSize <= CurrentMaxMutationLen && "Mutator return oversized unit");
+ Size = NewSize;
+ II.NumExecutedMutations++;
+ Corpus.IncrementNumExecutedMutations();
+
+ bool FoundUniqFeatures = false;
+ bool NewCov = RunOne(CurrentUnitData, Size, /*MayDeleteFile=*/true, &II,
+ &FoundUniqFeatures);
+ TryDetectingAMemoryLeak(CurrentUnitData, Size,
+ /*DuringInitialCorpusExecution*/ false);
+ if (NewCov) {
+ ReportNewCoverage(&II, {CurrentUnitData, CurrentUnitData + Size});
+ break; // We will mutate this input more in the next rounds.
+ }
+ if (Options.ReduceDepth && !FoundUniqFeatures)
+ break;
+ }
+
+ II.NeedsEnergyUpdate = true;
+ return false;
+}
+
+void Fuzzer::PurgeAllocator() {
+ if (Options.PurgeAllocatorIntervalSec < 0 || !EF->__sanitizer_purge_allocator)
+ return;
+ if (duration_cast<seconds>(system_clock::now() -
+ LastAllocatorPurgeAttemptTime)
+ .count() < Options.PurgeAllocatorIntervalSec)
+ return;
+
+ if (Options.RssLimitMb <= 0 ||
+ GetPeakRSSMb() > static_cast<size_t>(Options.RssLimitMb) / 2)
+ EF->__sanitizer_purge_allocator();
+
+ LastAllocatorPurgeAttemptTime = system_clock::now();
+}
+
+int Fuzzer::ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles) {
+ const size_t kMaxSaneLen = 1 << 20;
+ const size_t kMinDefaultLen = 4096;
+ size_t MaxSize = 0;
+ size_t MinSize = -1;
+ size_t TotalSize = 0;
+ for (auto &File : CorporaFiles) {
+ MaxSize = Max(File.Size, MaxSize);
+ MinSize = Min(File.Size, MinSize);
+ TotalSize += File.Size;
+ }
+ if (Options.MaxLen == 0)
+ SetMaxInputLen(std::min(std::max(kMinDefaultLen, MaxSize), kMaxSaneLen));
+ assert(MaxInputLen > 0);
+
+ // Test the callback with empty input and never try it again.
+ uint8_t dummy = 0;
+ ExecuteCallback(&dummy, 0);
+
+ if (CorporaFiles.empty()) {
+ Printf("INFO: A corpus is not provided, starting from an empty corpus\n");
+ Unit U({'\n'}); // Valid ASCII input.
+ RunOne(U.data(), U.size());
+ } else {
+ Printf("INFO: seed corpus: files: %zd min: %zdb max: %zdb total: %zdb"
+ " rss: %zdMb\n",
+ CorporaFiles.size(), MinSize, MaxSize, TotalSize, GetPeakRSSMb());
+ if (Options.ShuffleAtStartUp)
+ std::shuffle(CorporaFiles.begin(), CorporaFiles.end(), MD.GetRand());
+
+ if (Options.PreferSmall) {
+ std::stable_sort(CorporaFiles.begin(), CorporaFiles.end());
+ assert(CorporaFiles.front().Size <= CorporaFiles.back().Size);
+ }
+
+ // Load and execute inputs one by one.
+ for (auto &SF : CorporaFiles) {
+ auto U = FileToVector(SF.File, MaxInputLen, /*ExitOnError=*/false);
+ assert(U.size() <= MaxInputLen);
+ RunOne(U.data(), U.size());
+ CheckExitOnSrcPosOrItem();
+ TryDetectingAMemoryLeak(U.data(), U.size(),
+ /*DuringInitialCorpusExecution*/ true);
+ }
+ }
+
+ PrintStats("INITED");
+ if (!Options.FocusFunction.empty()) {
+ Printf("INFO: %zd/%zd inputs touch the focus function\n",
+ Corpus.NumInputsThatTouchFocusFunction(), Corpus.size());
+ if (!Options.DataFlowTrace.empty())
+ Printf("INFO: %zd/%zd inputs have the Data Flow Trace\n",
+ Corpus.NumInputsWithDataFlowTrace(),
+ Corpus.NumInputsThatTouchFocusFunction());
+ }
+
+ if (Corpus.empty() && Options.MaxNumberOfRuns) {
+ Printf("ERROR: no interesting inputs were found. "
+ "Is the code instrumented for coverage? Exiting.\n");
+ return 1;
+ }
+ return 0;
+}
+
+int Fuzzer::Loop(Vector<SizedFile> &CorporaFiles) {
+ auto FocusFunctionOrAuto = Options.FocusFunction;
+ int Res = DFT.Init(Options.DataFlowTrace, &FocusFunctionOrAuto, CorporaFiles,
+ MD.GetRand());
+ if (Res != 0)
+ return Res;
+ Res = TPC.SetFocusFunction(FocusFunctionOrAuto);
+ if (Res != 0)
+ return Res;
+ Res = ReadAndExecuteSeedCorpora(CorporaFiles);
+ if (Res != 0)
+ return Res;
+ DFT.Clear(); // No need for DFT any more.
+ TPC.SetPrintNewPCs(Options.PrintNewCovPcs);
+ TPC.SetPrintNewFuncs(Options.PrintNewCovFuncs);
+ system_clock::time_point LastCorpusReload = system_clock::now();
+
+ TmpMaxMutationLen =
+ Min(MaxMutationLen, Max(size_t(4), Corpus.MaxInputSize()));
+
+ while (true) {
+ auto Now = system_clock::now();
+ if (!Options.StopFile.empty() &&
+ !FileToVector(Options.StopFile, 1, false).empty())
+ break;
+ if (duration_cast<seconds>(Now - LastCorpusReload).count() >=
+ Options.ReloadIntervalSec) {
+ RereadOutputCorpus(MaxInputLen);
+ LastCorpusReload = system_clock::now();
+ }
+ if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+ break;
+ if (TimedOut())
+ break;
+
+ // Update TmpMaxMutationLen
+ if (Options.LenControl) {
+ if (TmpMaxMutationLen < MaxMutationLen &&
+ TotalNumberOfRuns - LastCorpusUpdateRun >
+ Options.LenControl * Log(TmpMaxMutationLen)) {
+ TmpMaxMutationLen =
+ Min(MaxMutationLen, TmpMaxMutationLen + Log(TmpMaxMutationLen));
+ LastCorpusUpdateRun = TotalNumberOfRuns;
+ }
+ } else {
+ TmpMaxMutationLen = MaxMutationLen;
+ }
+
+ // Perform several mutations and runs.
+ if (MutateAndTestOne())
+ return 0;
+
+ PurgeAllocator();
+ }
+
+ PrintStats("DONE ", "\n");
+ MD.PrintRecommendedDictionary();
+ return 0;
+}
+
+void Fuzzer::MinimizeCrashLoop(const Unit &U) {
+ if (U.size() <= 1)
+ return;
+ while (!TimedOut() && TotalNumberOfRuns < Options.MaxNumberOfRuns) {
+ MD.StartMutationSequence();
+ memcpy(CurrentUnitData, U.data(), U.size());
+ for (int i = 0; i < Options.MutateDepth; i++) {
+ size_t NewSize = MD.Mutate(CurrentUnitData, U.size(), MaxMutationLen);
+ assert(NewSize <= MaxMutationLen);
+ if (!NewSize)
+ continue;
+ ExecuteCallback(CurrentUnitData, NewSize);
+ PrintPulseAndReportSlowInput(CurrentUnitData, NewSize);
+ TryDetectingAMemoryLeak(CurrentUnitData, NewSize,
+ /*DuringInitialCorpusExecution*/ false);
+ }
+ }
+}
+
+} // namespace fuzzer
+
+extern "C" {
+
+ATTRIBUTE_INTERFACE size_t
+LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize) {
+ assert(fuzzer::F);
+ return fuzzer::F->GetMD().DefaultMutate(Data, Size, MaxSize);
+}
+
+} // extern "C"
diff --git a/tools/fuzzing/libfuzzer/FuzzerMain.cpp b/tools/fuzzing/libfuzzer/FuzzerMain.cpp
new file mode 100644
index 0000000000..75f2f8e75c
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerMain.cpp
@@ -0,0 +1,21 @@
+//===- FuzzerMain.cpp - main() function and flags -------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// main() and flags.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDefs.h"
+#include "FuzzerPlatform.h"
+
+extern "C" {
+// This function should be defined by the user.
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);
+} // extern "C"
+
+ATTRIBUTE_INTERFACE int main(int argc, char **argv) {
+ return fuzzer::FuzzerDriver(&argc, &argv, LLVMFuzzerTestOneInput);
+}
diff --git a/tools/fuzzing/libfuzzer/FuzzerMerge.cpp b/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
new file mode 100644
index 0000000000..0a185c7325
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
@@ -0,0 +1,419 @@
+//===- FuzzerMerge.cpp - merging corpora ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Merging corpora.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerCommand.h"
+#include "FuzzerMerge.h"
+#include "FuzzerIO.h"
+#include "FuzzerInternal.h"
+#include "FuzzerTracePC.h"
+#include "FuzzerUtil.h"
+
+#include <fstream>
+#include <iterator>
+#include <set>
+#include <sstream>
+#include <unordered_set>
+
+namespace fuzzer {
+
+bool Merger::Parse(const std::string &Str, bool ParseCoverage) {
+ std::istringstream SS(Str);
+ return Parse(SS, ParseCoverage);
+}
+
+int Merger::ParseOrExit(std::istream &IS, bool ParseCoverage) {
+ if (!Parse(IS, ParseCoverage)) {
+ Printf("MERGE: failed to parse the control file (unexpected error)\n");
+ return 1;
+ }
+ return 0;
+}
+
+// The control file example:
+//
+// 3 # The number of inputs
+// 1 # The number of inputs in the first corpus, <= the previous number
+// file0
+// file1
+// file2 # One file name per line.
+// STARTED 0 123 # FileID, file size
+// FT 0 1 4 6 8 # FileID COV1 COV2 ...
+// COV 0 7 8 9 # FileID COV1 COV1
+// STARTED 1 456 # If FT is missing, the input crashed while processing.
+// STARTED 2 567
+// FT 2 8 9
+// COV 2 11 12
+bool Merger::Parse(std::istream &IS, bool ParseCoverage) {
+ LastFailure.clear();
+ std::string Line;
+
+ // Parse NumFiles.
+ if (!std::getline(IS, Line, '\n')) return false;
+ std::istringstream L1(Line);
+ size_t NumFiles = 0;
+ L1 >> NumFiles;
+ if (NumFiles == 0 || NumFiles > 10000000) return false;
+
+ // Parse NumFilesInFirstCorpus.
+ if (!std::getline(IS, Line, '\n')) return false;
+ std::istringstream L2(Line);
+ NumFilesInFirstCorpus = NumFiles + 1;
+ L2 >> NumFilesInFirstCorpus;
+ if (NumFilesInFirstCorpus > NumFiles) return false;
+
+ // Parse file names.
+ Files.resize(NumFiles);
+ for (size_t i = 0; i < NumFiles; i++)
+ if (!std::getline(IS, Files[i].Name, '\n'))
+ return false;
+
+ // Parse STARTED, FT, and COV lines.
+ size_t ExpectedStartMarker = 0;
+ const size_t kInvalidStartMarker = -1;
+ size_t LastSeenStartMarker = kInvalidStartMarker;
+ Vector<uint32_t> TmpFeatures;
+ Set<uint32_t> PCs;
+ while (std::getline(IS, Line, '\n')) {
+ std::istringstream ISS1(Line);
+ std::string Marker;
+ size_t N;
+ ISS1 >> Marker;
+ ISS1 >> N;
+ if (Marker == "STARTED") {
+ // STARTED FILE_ID FILE_SIZE
+ if (ExpectedStartMarker != N)
+ return false;
+ ISS1 >> Files[ExpectedStartMarker].Size;
+ LastSeenStartMarker = ExpectedStartMarker;
+ assert(ExpectedStartMarker < Files.size());
+ ExpectedStartMarker++;
+ } else if (Marker == "FT") {
+ // FT FILE_ID COV1 COV2 COV3 ...
+ size_t CurrentFileIdx = N;
+ if (CurrentFileIdx != LastSeenStartMarker)
+ return false;
+ LastSeenStartMarker = kInvalidStartMarker;
+ if (ParseCoverage) {
+ TmpFeatures.clear(); // use a vector from outer scope to avoid resizes.
+ while (ISS1 >> N)
+ TmpFeatures.push_back(N);
+ std::sort(TmpFeatures.begin(), TmpFeatures.end());
+ Files[CurrentFileIdx].Features = TmpFeatures;
+ }
+ } else if (Marker == "COV") {
+ size_t CurrentFileIdx = N;
+ if (ParseCoverage)
+ while (ISS1 >> N)
+ if (PCs.insert(N).second)
+ Files[CurrentFileIdx].Cov.push_back(N);
+ } else {
+ return false;
+ }
+ }
+ if (LastSeenStartMarker != kInvalidStartMarker)
+ LastFailure = Files[LastSeenStartMarker].Name;
+
+ FirstNotProcessedFile = ExpectedStartMarker;
+ return true;
+}
+
+size_t Merger::ApproximateMemoryConsumption() const {
+ size_t Res = 0;
+ for (const auto &F: Files)
+ Res += sizeof(F) + F.Features.size() * sizeof(F.Features[0]);
+ return Res;
+}
+
+// Decides which files need to be merged (add those to NewFiles).
+// Returns the number of new features added.
+size_t Merger::Merge(const Set<uint32_t> &InitialFeatures,
+ Set<uint32_t> *NewFeatures,
+ const Set<uint32_t> &InitialCov, Set<uint32_t> *NewCov,
+ Vector<std::string> *NewFiles) {
+ NewFiles->clear();
+ assert(NumFilesInFirstCorpus <= Files.size());
+ Set<uint32_t> AllFeatures = InitialFeatures;
+
+ // What features are in the initial corpus?
+ for (size_t i = 0; i < NumFilesInFirstCorpus; i++) {
+ auto &Cur = Files[i].Features;
+ AllFeatures.insert(Cur.begin(), Cur.end());
+ }
+ // Remove all features that we already know from all other inputs.
+ for (size_t i = NumFilesInFirstCorpus; i < Files.size(); i++) {
+ auto &Cur = Files[i].Features;
+ Vector<uint32_t> Tmp;
+ std::set_difference(Cur.begin(), Cur.end(), AllFeatures.begin(),
+ AllFeatures.end(), std::inserter(Tmp, Tmp.begin()));
+ Cur.swap(Tmp);
+ }
+
+ // Sort. Give preference to
+ // * smaller files
+ // * files with more features.
+ std::sort(Files.begin() + NumFilesInFirstCorpus, Files.end(),
+ [&](const MergeFileInfo &a, const MergeFileInfo &b) -> bool {
+ if (a.Size != b.Size)
+ return a.Size < b.Size;
+ return a.Features.size() > b.Features.size();
+ });
+
+ // One greedy pass: add the file's features to AllFeatures.
+ // If new features were added, add this file to NewFiles.
+ for (size_t i = NumFilesInFirstCorpus; i < Files.size(); i++) {
+ auto &Cur = Files[i].Features;
+ // Printf("%s -> sz %zd ft %zd\n", Files[i].Name.c_str(),
+ // Files[i].Size, Cur.size());
+ bool FoundNewFeatures = false;
+ for (auto Fe: Cur) {
+ if (AllFeatures.insert(Fe).second) {
+ FoundNewFeatures = true;
+ NewFeatures->insert(Fe);
+ }
+ }
+ if (FoundNewFeatures)
+ NewFiles->push_back(Files[i].Name);
+ for (auto Cov : Files[i].Cov)
+ if (InitialCov.find(Cov) == InitialCov.end())
+ NewCov->insert(Cov);
+ }
+ return NewFeatures->size();
+}
+
+Set<uint32_t> Merger::AllFeatures() const {
+ Set<uint32_t> S;
+ for (auto &File : Files)
+ S.insert(File.Features.begin(), File.Features.end());
+ return S;
+}
+
+// Inner process. May crash if the target crashes.
+int Fuzzer::CrashResistantMergeInternalStep(const std::string &CFPath) {
+ Printf("MERGE-INNER: using the control file '%s'\n", CFPath.c_str());
+ Merger M;
+ std::ifstream IF(CFPath);
+ int Res = M.ParseOrExit(IF, false);
+ if (Res != 0)
+ return Res;
+ IF.close();
+ if (!M.LastFailure.empty())
+ Printf("MERGE-INNER: '%s' caused a failure at the previous merge step\n",
+ M.LastFailure.c_str());
+
+ Printf("MERGE-INNER: %zd total files;"
+ " %zd processed earlier; will process %zd files now\n",
+ M.Files.size(), M.FirstNotProcessedFile,
+ M.Files.size() - M.FirstNotProcessedFile);
+
+ std::ofstream OF(CFPath, std::ofstream::out | std::ofstream::app);
+ Set<size_t> AllFeatures;
+ auto PrintStatsWrapper = [this, &AllFeatures](const char* Where) {
+ this->PrintStats(Where, "\n", 0, AllFeatures.size());
+ };
+ Set<const TracePC::PCTableEntry *> AllPCs;
+ for (size_t i = M.FirstNotProcessedFile; i < M.Files.size(); i++) {
+ if (Fuzzer::MaybeExitGracefully())
+ return 0;
+ auto U = FileToVector(M.Files[i].Name);
+ if (U.size() > MaxInputLen) {
+ U.resize(MaxInputLen);
+ U.shrink_to_fit();
+ }
+
+ // Write the pre-run marker.
+ OF << "STARTED " << i << " " << U.size() << "\n";
+ OF.flush(); // Flush is important since Command::Execute may crash.
+ // Run.
+ TPC.ResetMaps();
+ if (ExecuteCallback(U.data(), U.size()) > 0) {
+ continue;
+ }
+ // Collect coverage. We are iterating over the files in this order:
+ // * First, files in the initial corpus ordered by size, smallest first.
+ // * Then, all other files, smallest first.
+ // So it makes no sense to record all features for all files, instead we
+ // only record features that were not seen before.
+ Set<size_t> UniqFeatures;
+ TPC.CollectFeatures([&](size_t Feature) {
+ if (AllFeatures.insert(Feature).second)
+ UniqFeatures.insert(Feature);
+ });
+ TPC.UpdateObservedPCs();
+ // Show stats.
+ if (!(TotalNumberOfRuns & (TotalNumberOfRuns - 1)))
+ PrintStatsWrapper("pulse ");
+ if (TotalNumberOfRuns == M.NumFilesInFirstCorpus)
+ PrintStatsWrapper("LOADED");
+ // Write the post-run marker and the coverage.
+ OF << "FT " << i;
+ for (size_t F : UniqFeatures)
+ OF << " " << F;
+ OF << "\n";
+ OF << "COV " << i;
+ TPC.ForEachObservedPC([&](const TracePC::PCTableEntry *TE) {
+ if (AllPCs.insert(TE).second)
+ OF << " " << TPC.PCTableEntryIdx(TE);
+ });
+ OF << "\n";
+ OF.flush();
+ }
+ PrintStatsWrapper("DONE ");
+ return 0;
+}
+
+static int WriteNewControlFile(const std::string &CFPath,
+ const Vector<SizedFile> &OldCorpus,
+ const Vector<SizedFile> &NewCorpus,
+ const Vector<MergeFileInfo> &KnownFiles,
+ size_t &NumFiles) {
+ std::unordered_set<std::string> FilesToSkip;
+ for (auto &SF: KnownFiles)
+ FilesToSkip.insert(SF.Name);
+
+ Vector<std::string> FilesToUse;
+ auto MaybeUseFile = [=, &FilesToUse](std::string Name) {
+ if (FilesToSkip.find(Name) == FilesToSkip.end())
+ FilesToUse.push_back(Name);
+ };
+ for (auto &SF: OldCorpus)
+ MaybeUseFile(SF.File);
+ auto FilesToUseFromOldCorpus = FilesToUse.size();
+ for (auto &SF: NewCorpus)
+ MaybeUseFile(SF.File);
+
+ RemoveFile(CFPath);
+ std::ofstream ControlFile(CFPath);
+ ControlFile << FilesToUse.size() << "\n";
+ ControlFile << FilesToUseFromOldCorpus << "\n";
+ for (auto &FN: FilesToUse)
+ ControlFile << FN << "\n";
+
+ if (!ControlFile) {
+ Printf("MERGE-OUTER: failed to write to the control file: %s\n",
+ CFPath.c_str());
+ return 1;
+ }
+
+ NumFiles = FilesToUse.size();
+ return 0;
+}
+
+// Outer process. Does not call the target code and thus should not fail.
+int CrashResistantMerge(const Vector<std::string> &Args,
+ const Vector<SizedFile> &OldCorpus,
+ const Vector<SizedFile> &NewCorpus,
+ Vector<std::string> *NewFiles,
+ const Set<uint32_t> &InitialFeatures,
+ Set<uint32_t> *NewFeatures,
+ const Set<uint32_t> &InitialCov,
+ Set<uint32_t> *NewCov,
+ const std::string &CFPath,
+ bool V /*Verbose*/) {
+ if (NewCorpus.empty() && OldCorpus.empty()) return 0; // Nothing to merge.
+ size_t NumAttempts = 0;
+ int Res;
+ Vector<MergeFileInfo> KnownFiles;
+ if (FileSize(CFPath)) {
+ VPrintf(V, "MERGE-OUTER: non-empty control file provided: '%s'\n",
+ CFPath.c_str());
+ Merger M;
+ std::ifstream IF(CFPath);
+ if (M.Parse(IF, /*ParseCoverage=*/true)) {
+ VPrintf(V, "MERGE-OUTER: control file ok, %zd files total,"
+ " first not processed file %zd\n",
+ M.Files.size(), M.FirstNotProcessedFile);
+ if (!M.LastFailure.empty())
+ VPrintf(V, "MERGE-OUTER: '%s' will be skipped as unlucky "
+ "(merge has stumbled on it the last time)\n",
+ M.LastFailure.c_str());
+ if (M.FirstNotProcessedFile >= M.Files.size()) {
+ // Merge has already been completed with the given merge control file.
+ if (M.Files.size() == OldCorpus.size() + NewCorpus.size()) {
+ VPrintf(
+ V,
+ "MERGE-OUTER: nothing to do, merge has been completed before\n");
+ Fuzzer::GracefullyExit();
+ return 0;
+ }
+
+ // Number of input files likely changed, start merge from scratch, but
+ // reuse coverage information from the given merge control file.
+ VPrintf(
+ V,
+ "MERGE-OUTER: starting merge from scratch, but reusing coverage "
+ "information from the given control file\n");
+ KnownFiles = M.Files;
+ } else {
+ // There is a merge in progress, continue.
+ NumAttempts = M.Files.size() - M.FirstNotProcessedFile;
+ }
+ } else {
+ VPrintf(V, "MERGE-OUTER: bad control file, will overwrite it\n");
+ }
+ }
+
+ if (!NumAttempts) {
+ // The supplied control file is empty or bad, create a fresh one.
+ VPrintf(V, "MERGE-OUTER: "
+ "%zd files, %zd in the initial corpus, %zd processed earlier\n",
+ OldCorpus.size() + NewCorpus.size(), OldCorpus.size(),
+ KnownFiles.size());
+ Res = WriteNewControlFile(CFPath, OldCorpus, NewCorpus, KnownFiles, NumAttempts);
+ if (Res != 0)
+ return Res;
+ }
+
+ // Execute the inner process until it passes.
+ // Every inner process should execute at least one input.
+ Command BaseCmd(Args);
+ BaseCmd.removeFlag("merge");
+ BaseCmd.removeFlag("fork");
+ BaseCmd.removeFlag("collect_data_flow");
+ for (size_t Attempt = 1; Attempt <= NumAttempts; Attempt++) {
+ if (Fuzzer::MaybeExitGracefully())
+ return 0;
+ VPrintf(V, "MERGE-OUTER: attempt %zd\n", Attempt);
+ Command Cmd(BaseCmd);
+ Cmd.addFlag("merge_control_file", CFPath);
+ Cmd.addFlag("merge_inner", "1");
+ if (!V) {
+ Cmd.setOutputFile(getDevNull());
+ Cmd.combineOutAndErr();
+ }
+ auto ExitCode = ExecuteCommand(Cmd);
+ if (!ExitCode) {
+ VPrintf(V, "MERGE-OUTER: succesfull in %zd attempt(s)\n", Attempt);
+ break;
+ }
+ }
+ // Read the control file and do the merge.
+ Merger M;
+ std::ifstream IF(CFPath);
+ IF.seekg(0, IF.end);
+ VPrintf(V, "MERGE-OUTER: the control file has %zd bytes\n",
+ (size_t)IF.tellg());
+ IF.seekg(0, IF.beg);
+ Res = M.ParseOrExit(IF, true);
+ if (Res != 0)
+ return Res;
+ IF.close();
+ VPrintf(V,
+ "MERGE-OUTER: consumed %zdMb (%zdMb rss) to parse the control file\n",
+ M.ApproximateMemoryConsumption() >> 20, GetPeakRSSMb());
+
+ M.Files.insert(M.Files.end(), KnownFiles.begin(), KnownFiles.end());
+ M.Merge(InitialFeatures, NewFeatures, InitialCov, NewCov, NewFiles);
+ VPrintf(V, "MERGE-OUTER: %zd new files with %zd new features added; "
+ "%zd new coverage edges\n",
+ NewFiles->size(), NewFeatures->size(), NewCov->size());
+ return 0;
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerMerge.h b/tools/fuzzing/libfuzzer/FuzzerMerge.h
new file mode 100644
index 0000000000..6dc1c4c45a
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerMerge.h
@@ -0,0 +1,87 @@
+//===- FuzzerMerge.h - merging corpa ----------------------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Merging Corpora.
+//
+// The task:
+// Take the existing corpus (possibly empty) and merge new inputs into
+// it so that only inputs with new coverage ('features') are added.
+// The process should tolerate the crashes, OOMs, leaks, etc.
+//
+// Algorithm:
+// The outer process collects the set of files and writes their names
+// into a temporary "control" file, then repeatedly launches the inner
+// process until all inputs are processed.
+// The outer process does not actually execute the target code.
+//
+// The inner process reads the control file and sees a) list of all the inputs
+// and b) the last processed input. Then it starts processing the inputs one
+// by one. Before processing every input it writes one line to control file:
+// STARTED INPUT_ID INPUT_SIZE
+// After processing an input it writes the following lines:
+// FT INPUT_ID Feature1 Feature2 Feature3 ...
+// COV INPUT_ID Coverage1 Coverage2 Coverage3 ...
+// If a crash happens while processing an input the last line in the control
+// file will be "STARTED INPUT_ID" and so the next process will know
+// where to resume.
+//
+// Once all inputs are processed by the inner process(es) the outer process
+// reads the control files and does the merge based entirely on the contents
+// of control file.
+// It uses a single pass greedy algorithm choosing first the smallest inputs
+// within the same size the inputs that have more new features.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_MERGE_H
+#define LLVM_FUZZER_MERGE_H
+
+#include "FuzzerDefs.h"
+
+#include <istream>
+#include <ostream>
+#include <set>
+#include <vector>
+
+namespace fuzzer {
+
+struct MergeFileInfo {
+ std::string Name;
+ size_t Size = 0;
+ Vector<uint32_t> Features, Cov;
+};
+
+struct Merger {
+ Vector<MergeFileInfo> Files;
+ size_t NumFilesInFirstCorpus = 0;
+ size_t FirstNotProcessedFile = 0;
+ std::string LastFailure;
+
+ bool Parse(std::istream &IS, bool ParseCoverage);
+ bool Parse(const std::string &Str, bool ParseCoverage);
+ int ParseOrExit(std::istream &IS, bool ParseCoverage);
+ size_t Merge(const Set<uint32_t> &InitialFeatures, Set<uint32_t> *NewFeatures,
+ const Set<uint32_t> &InitialCov, Set<uint32_t> *NewCov,
+ Vector<std::string> *NewFiles);
+ size_t ApproximateMemoryConsumption() const;
+ Set<uint32_t> AllFeatures() const;
+};
+
+int CrashResistantMerge(const Vector<std::string> &Args,
+ const Vector<SizedFile> &OldCorpus,
+ const Vector<SizedFile> &NewCorpus,
+ Vector<std::string> *NewFiles,
+ const Set<uint32_t> &InitialFeatures,
+ Set<uint32_t> *NewFeatures,
+ const Set<uint32_t> &InitialCov,
+ Set<uint32_t> *NewCov,
+ const std::string &CFPath,
+ bool Verbose);
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_MERGE_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerMutate.cpp b/tools/fuzzing/libfuzzer/FuzzerMutate.cpp
new file mode 100644
index 0000000000..29541eac5d
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerMutate.cpp
@@ -0,0 +1,562 @@
+//===- FuzzerMutate.cpp - Mutate a test input -----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Mutate a test input.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDefs.h"
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include "FuzzerMutate.h"
+#include "FuzzerOptions.h"
+#include "FuzzerTracePC.h"
+
+namespace fuzzer {
+
+const size_t Dictionary::kMaxDictSize;
+
+static void PrintASCII(const Word &W, const char *PrintAfter) {
+ PrintASCII(W.data(), W.size(), PrintAfter);
+}
+
+MutationDispatcher::MutationDispatcher(Random &Rand,
+ const FuzzingOptions &Options)
+ : Rand(Rand), Options(Options) {
+ DefaultMutators.insert(
+ DefaultMutators.begin(),
+ {
+ {&MutationDispatcher::Mutate_EraseBytes, "EraseBytes"},
+ {&MutationDispatcher::Mutate_InsertByte, "InsertByte"},
+ {&MutationDispatcher::Mutate_InsertRepeatedBytes,
+ "InsertRepeatedBytes"},
+ {&MutationDispatcher::Mutate_ChangeByte, "ChangeByte"},
+ {&MutationDispatcher::Mutate_ChangeBit, "ChangeBit"},
+ {&MutationDispatcher::Mutate_ShuffleBytes, "ShuffleBytes"},
+ {&MutationDispatcher::Mutate_ChangeASCIIInteger, "ChangeASCIIInt"},
+ {&MutationDispatcher::Mutate_ChangeBinaryInteger, "ChangeBinInt"},
+ {&MutationDispatcher::Mutate_CopyPart, "CopyPart"},
+ {&MutationDispatcher::Mutate_CrossOver, "CrossOver"},
+ {&MutationDispatcher::Mutate_AddWordFromManualDictionary,
+ "ManualDict"},
+ {&MutationDispatcher::Mutate_AddWordFromPersistentAutoDictionary,
+ "PersAutoDict"},
+ });
+ if(Options.UseCmp)
+ DefaultMutators.push_back(
+ {&MutationDispatcher::Mutate_AddWordFromTORC, "CMP"});
+
+ if (EF->LLVMFuzzerCustomMutator)
+ Mutators.push_back({&MutationDispatcher::Mutate_Custom, "Custom"});
+ else
+ Mutators = DefaultMutators;
+
+ if (EF->LLVMFuzzerCustomCrossOver)
+ Mutators.push_back(
+ {&MutationDispatcher::Mutate_CustomCrossOver, "CustomCrossOver"});
+}
+
+static char RandCh(Random &Rand) {
+ if (Rand.RandBool()) return Rand(256);
+ const char Special[] = "!*'();:@&=+$,/?%#[]012Az-`~.\xff\x00";
+ return Special[Rand(sizeof(Special) - 1)];
+}
+
+size_t MutationDispatcher::Mutate_Custom(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ return EF->LLVMFuzzerCustomMutator(Data, Size, MaxSize, Rand.Rand());
+}
+
+size_t MutationDispatcher::Mutate_CustomCrossOver(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size == 0)
+ return 0;
+ if (!CrossOverWith) return 0;
+ const Unit &Other = *CrossOverWith;
+ if (Other.empty())
+ return 0;
+ CustomCrossOverInPlaceHere.resize(MaxSize);
+ auto &U = CustomCrossOverInPlaceHere;
+ size_t NewSize = EF->LLVMFuzzerCustomCrossOver(
+ Data, Size, Other.data(), Other.size(), U.data(), U.size(), Rand.Rand());
+ if (!NewSize)
+ return 0;
+ assert(NewSize <= MaxSize && "CustomCrossOver returned overisized unit");
+ memcpy(Data, U.data(), NewSize);
+ return NewSize;
+}
+
+size_t MutationDispatcher::Mutate_ShuffleBytes(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize || Size == 0) return 0;
+ size_t ShuffleAmount =
+ Rand(std::min(Size, (size_t)8)) + 1; // [1,8] and <= Size.
+ size_t ShuffleStart = Rand(Size - ShuffleAmount);
+ assert(ShuffleStart + ShuffleAmount <= Size);
+ std::shuffle(Data + ShuffleStart, Data + ShuffleStart + ShuffleAmount, Rand);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_EraseBytes(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size <= 1) return 0;
+ size_t N = Rand(Size / 2) + 1;
+ assert(N < Size);
+ size_t Idx = Rand(Size - N + 1);
+ // Erase Data[Idx:Idx+N].
+ memmove(Data + Idx, Data + Idx + N, Size - Idx - N);
+ // Printf("Erase: %zd %zd => %zd; Idx %zd\n", N, Size, Size - N, Idx);
+ return Size - N;
+}
+
+size_t MutationDispatcher::Mutate_InsertByte(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size >= MaxSize) return 0;
+ size_t Idx = Rand(Size + 1);
+ // Insert new value at Data[Idx].
+ memmove(Data + Idx + 1, Data + Idx, Size - Idx);
+ Data[Idx] = RandCh(Rand);
+ return Size + 1;
+}
+
+size_t MutationDispatcher::Mutate_InsertRepeatedBytes(uint8_t *Data,
+ size_t Size,
+ size_t MaxSize) {
+ const size_t kMinBytesToInsert = 3;
+ if (Size + kMinBytesToInsert >= MaxSize) return 0;
+ size_t MaxBytesToInsert = std::min(MaxSize - Size, (size_t)128);
+ size_t N = Rand(MaxBytesToInsert - kMinBytesToInsert + 1) + kMinBytesToInsert;
+ assert(Size + N <= MaxSize && N);
+ size_t Idx = Rand(Size + 1);
+ // Insert new values at Data[Idx].
+ memmove(Data + Idx + N, Data + Idx, Size - Idx);
+ // Give preference to 0x00 and 0xff.
+ uint8_t Byte = Rand.RandBool() ? Rand(256) : (Rand.RandBool() ? 0 : 255);
+ for (size_t i = 0; i < N; i++)
+ Data[Idx + i] = Byte;
+ return Size + N;
+}
+
+size_t MutationDispatcher::Mutate_ChangeByte(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ size_t Idx = Rand(Size);
+ Data[Idx] = RandCh(Rand);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_ChangeBit(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ size_t Idx = Rand(Size);
+ Data[Idx] ^= 1 << Rand(8);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_AddWordFromManualDictionary(uint8_t *Data,
+ size_t Size,
+ size_t MaxSize) {
+ return AddWordFromDictionary(ManualDictionary, Data, Size, MaxSize);
+}
+
+size_t MutationDispatcher::ApplyDictionaryEntry(uint8_t *Data, size_t Size,
+ size_t MaxSize,
+ DictionaryEntry &DE) {
+ const Word &W = DE.GetW();
+ bool UsePositionHint = DE.HasPositionHint() &&
+ DE.GetPositionHint() + W.size() < Size &&
+ Rand.RandBool();
+ if (Rand.RandBool()) { // Insert W.
+ if (Size + W.size() > MaxSize) return 0;
+ size_t Idx = UsePositionHint ? DE.GetPositionHint() : Rand(Size + 1);
+ memmove(Data + Idx + W.size(), Data + Idx, Size - Idx);
+ memcpy(Data + Idx, W.data(), W.size());
+ Size += W.size();
+ } else { // Overwrite some bytes with W.
+ if (W.size() > Size) return 0;
+ size_t Idx = UsePositionHint ? DE.GetPositionHint() : Rand(Size - W.size());
+ memcpy(Data + Idx, W.data(), W.size());
+ }
+ return Size;
+}
+
+// Somewhere in the past we have observed a comparison instructions
+// with arguments Arg1 Arg2. This function tries to guess a dictionary
+// entry that will satisfy that comparison.
+// It first tries to find one of the arguments (possibly swapped) in the
+// input and if it succeeds it creates a DE with a position hint.
+// Otherwise it creates a DE with one of the arguments w/o a position hint.
+DictionaryEntry MutationDispatcher::MakeDictionaryEntryFromCMP(
+ const void *Arg1, const void *Arg2,
+ const void *Arg1Mutation, const void *Arg2Mutation,
+ size_t ArgSize, const uint8_t *Data,
+ size_t Size) {
+ bool HandleFirst = Rand.RandBool();
+ const void *ExistingBytes, *DesiredBytes;
+ Word W;
+ const uint8_t *End = Data + Size;
+ for (int Arg = 0; Arg < 2; Arg++) {
+ ExistingBytes = HandleFirst ? Arg1 : Arg2;
+ DesiredBytes = HandleFirst ? Arg2Mutation : Arg1Mutation;
+ HandleFirst = !HandleFirst;
+ W.Set(reinterpret_cast<const uint8_t*>(DesiredBytes), ArgSize);
+ const size_t kMaxNumPositions = 8;
+ size_t Positions[kMaxNumPositions];
+ size_t NumPositions = 0;
+ for (const uint8_t *Cur = Data;
+ Cur < End && NumPositions < kMaxNumPositions; Cur++) {
+ Cur =
+ (const uint8_t *)SearchMemory(Cur, End - Cur, ExistingBytes, ArgSize);
+ if (!Cur) break;
+ Positions[NumPositions++] = Cur - Data;
+ }
+ if (!NumPositions) continue;
+ return DictionaryEntry(W, Positions[Rand(NumPositions)]);
+ }
+ DictionaryEntry DE(W);
+ return DE;
+}
+
+
+template <class T>
+DictionaryEntry MutationDispatcher::MakeDictionaryEntryFromCMP(
+ T Arg1, T Arg2, const uint8_t *Data, size_t Size) {
+ if (Rand.RandBool()) Arg1 = Bswap(Arg1);
+ if (Rand.RandBool()) Arg2 = Bswap(Arg2);
+ T Arg1Mutation = Arg1 + Rand(-1, 1);
+ T Arg2Mutation = Arg2 + Rand(-1, 1);
+ return MakeDictionaryEntryFromCMP(&Arg1, &Arg2, &Arg1Mutation, &Arg2Mutation,
+ sizeof(Arg1), Data, Size);
+}
+
+DictionaryEntry MutationDispatcher::MakeDictionaryEntryFromCMP(
+ const Word &Arg1, const Word &Arg2, const uint8_t *Data, size_t Size) {
+ return MakeDictionaryEntryFromCMP(Arg1.data(), Arg2.data(), Arg1.data(),
+ Arg2.data(), Arg1.size(), Data, Size);
+}
+
+size_t MutationDispatcher::Mutate_AddWordFromTORC(
+ uint8_t *Data, size_t Size, size_t MaxSize) {
+ Word W;
+ DictionaryEntry DE;
+ switch (Rand(4)) {
+ case 0: {
+ auto X = TPC.TORC8.Get(Rand.Rand());
+ DE = MakeDictionaryEntryFromCMP(X.A, X.B, Data, Size);
+ } break;
+ case 1: {
+ auto X = TPC.TORC4.Get(Rand.Rand());
+ if ((X.A >> 16) == 0 && (X.B >> 16) == 0 && Rand.RandBool())
+ DE = MakeDictionaryEntryFromCMP((uint16_t)X.A, (uint16_t)X.B, Data, Size);
+ else
+ DE = MakeDictionaryEntryFromCMP(X.A, X.B, Data, Size);
+ } break;
+ case 2: {
+ auto X = TPC.TORCW.Get(Rand.Rand());
+ DE = MakeDictionaryEntryFromCMP(X.A, X.B, Data, Size);
+ } break;
+ case 3: if (Options.UseMemmem) {
+ auto X = TPC.MMT.Get(Rand.Rand());
+ DE = DictionaryEntry(X);
+ } break;
+ default:
+ assert(0);
+ }
+ if (!DE.GetW().size()) return 0;
+ Size = ApplyDictionaryEntry(Data, Size, MaxSize, DE);
+ if (!Size) return 0;
+ DictionaryEntry &DERef =
+ CmpDictionaryEntriesDeque[CmpDictionaryEntriesDequeIdx++ %
+ kCmpDictionaryEntriesDequeSize];
+ DERef = DE;
+ CurrentDictionaryEntrySequence.push_back(&DERef);
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_AddWordFromPersistentAutoDictionary(
+ uint8_t *Data, size_t Size, size_t MaxSize) {
+ return AddWordFromDictionary(PersistentAutoDictionary, Data, Size, MaxSize);
+}
+
+size_t MutationDispatcher::AddWordFromDictionary(Dictionary &D, uint8_t *Data,
+ size_t Size, size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ if (D.empty()) return 0;
+ DictionaryEntry &DE = D[Rand(D.size())];
+ Size = ApplyDictionaryEntry(Data, Size, MaxSize, DE);
+ if (!Size) return 0;
+ DE.IncUseCount();
+ CurrentDictionaryEntrySequence.push_back(&DE);
+ return Size;
+}
+
+// Overwrites part of To[0,ToSize) with a part of From[0,FromSize).
+// Returns ToSize.
+size_t MutationDispatcher::CopyPartOf(const uint8_t *From, size_t FromSize,
+ uint8_t *To, size_t ToSize) {
+ // Copy From[FromBeg, FromBeg + CopySize) into To[ToBeg, ToBeg + CopySize).
+ size_t ToBeg = Rand(ToSize);
+ size_t CopySize = Rand(ToSize - ToBeg) + 1;
+ assert(ToBeg + CopySize <= ToSize);
+ CopySize = std::min(CopySize, FromSize);
+ size_t FromBeg = Rand(FromSize - CopySize + 1);
+ assert(FromBeg + CopySize <= FromSize);
+ memmove(To + ToBeg, From + FromBeg, CopySize);
+ return ToSize;
+}
+
+// Inserts part of From[0,ToSize) into To.
+// Returns new size of To on success or 0 on failure.
+size_t MutationDispatcher::InsertPartOf(const uint8_t *From, size_t FromSize,
+ uint8_t *To, size_t ToSize,
+ size_t MaxToSize) {
+ if (ToSize >= MaxToSize) return 0;
+ size_t AvailableSpace = MaxToSize - ToSize;
+ size_t MaxCopySize = std::min(AvailableSpace, FromSize);
+ size_t CopySize = Rand(MaxCopySize) + 1;
+ size_t FromBeg = Rand(FromSize - CopySize + 1);
+ assert(FromBeg + CopySize <= FromSize);
+ size_t ToInsertPos = Rand(ToSize + 1);
+ assert(ToInsertPos + CopySize <= MaxToSize);
+ size_t TailSize = ToSize - ToInsertPos;
+ if (To == From) {
+ MutateInPlaceHere.resize(MaxToSize);
+ memcpy(MutateInPlaceHere.data(), From + FromBeg, CopySize);
+ memmove(To + ToInsertPos + CopySize, To + ToInsertPos, TailSize);
+ memmove(To + ToInsertPos, MutateInPlaceHere.data(), CopySize);
+ } else {
+ memmove(To + ToInsertPos + CopySize, To + ToInsertPos, TailSize);
+ memmove(To + ToInsertPos, From + FromBeg, CopySize);
+ }
+ return ToSize + CopySize;
+}
+
+size_t MutationDispatcher::Mutate_CopyPart(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize || Size == 0) return 0;
+ // If Size == MaxSize, `InsertPartOf(...)` will
+ // fail so there's no point using it in this case.
+ if (Size == MaxSize || Rand.RandBool())
+ return CopyPartOf(Data, Size, Data, Size);
+ else
+ return InsertPartOf(Data, Size, Data, Size, MaxSize);
+}
+
+size_t MutationDispatcher::Mutate_ChangeASCIIInteger(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ size_t B = Rand(Size);
+ while (B < Size && !isdigit(Data[B])) B++;
+ if (B == Size) return 0;
+ size_t E = B;
+ while (E < Size && isdigit(Data[E])) E++;
+ assert(B < E);
+ // now we have digits in [B, E).
+ // strtol and friends don't accept non-zero-teminated data, parse it manually.
+ uint64_t Val = Data[B] - '0';
+ for (size_t i = B + 1; i < E; i++)
+ Val = Val * 10 + Data[i] - '0';
+
+ // Mutate the integer value.
+ switch(Rand(5)) {
+ case 0: Val++; break;
+ case 1: Val--; break;
+ case 2: Val /= 2; break;
+ case 3: Val *= 2; break;
+ case 4: Val = Rand(Val * Val); break;
+ default: assert(0);
+ }
+ // Just replace the bytes with the new ones, don't bother moving bytes.
+ for (size_t i = B; i < E; i++) {
+ size_t Idx = E + B - i - 1;
+ assert(Idx >= B && Idx < E);
+ Data[Idx] = (Val % 10) + '0';
+ Val /= 10;
+ }
+ return Size;
+}
+
+template<class T>
+size_t ChangeBinaryInteger(uint8_t *Data, size_t Size, Random &Rand) {
+ if (Size < sizeof(T)) return 0;
+ size_t Off = Rand(Size - sizeof(T) + 1);
+ assert(Off + sizeof(T) <= Size);
+ T Val;
+ if (Off < 64 && !Rand(4)) {
+ Val = Size;
+ if (Rand.RandBool())
+ Val = Bswap(Val);
+ } else {
+ memcpy(&Val, Data + Off, sizeof(Val));
+ T Add = Rand(21);
+ Add -= 10;
+ if (Rand.RandBool())
+ Val = Bswap(T(Bswap(Val) + Add)); // Add assuming different endiannes.
+ else
+ Val = Val + Add; // Add assuming current endiannes.
+ if (Add == 0 || Rand.RandBool()) // Maybe negate.
+ Val = -Val;
+ }
+ memcpy(Data + Off, &Val, sizeof(Val));
+ return Size;
+}
+
+size_t MutationDispatcher::Mutate_ChangeBinaryInteger(uint8_t *Data,
+ size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ switch (Rand(4)) {
+ case 3: return ChangeBinaryInteger<uint64_t>(Data, Size, Rand);
+ case 2: return ChangeBinaryInteger<uint32_t>(Data, Size, Rand);
+ case 1: return ChangeBinaryInteger<uint16_t>(Data, Size, Rand);
+ case 0: return ChangeBinaryInteger<uint8_t>(Data, Size, Rand);
+ default: assert(0);
+ }
+ return 0;
+}
+
+size_t MutationDispatcher::Mutate_CrossOver(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ if (Size > MaxSize) return 0;
+ if (Size == 0) return 0;
+ if (!CrossOverWith) return 0;
+ const Unit &O = *CrossOverWith;
+ if (O.empty()) return 0;
+ MutateInPlaceHere.resize(MaxSize);
+ auto &U = MutateInPlaceHere;
+ size_t NewSize = 0;
+ switch(Rand(3)) {
+ case 0:
+ NewSize = CrossOver(Data, Size, O.data(), O.size(), U.data(), U.size());
+ break;
+ case 1:
+ NewSize = InsertPartOf(O.data(), O.size(), U.data(), U.size(), MaxSize);
+ if (!NewSize)
+ NewSize = CopyPartOf(O.data(), O.size(), U.data(), U.size());
+ break;
+ case 2:
+ NewSize = CopyPartOf(O.data(), O.size(), U.data(), U.size());
+ break;
+ default: assert(0);
+ }
+ assert(NewSize > 0 && "CrossOver returned empty unit");
+ assert(NewSize <= MaxSize && "CrossOver returned overisized unit");
+ memcpy(Data, U.data(), NewSize);
+ return NewSize;
+}
+
+void MutationDispatcher::StartMutationSequence() {
+ CurrentMutatorSequence.clear();
+ CurrentDictionaryEntrySequence.clear();
+}
+
+// Copy successful dictionary entries to PersistentAutoDictionary.
+void MutationDispatcher::RecordSuccessfulMutationSequence() {
+ for (auto DE : CurrentDictionaryEntrySequence) {
+ // PersistentAutoDictionary.AddWithSuccessCountOne(DE);
+ DE->IncSuccessCount();
+ assert(DE->GetW().size());
+ // Linear search is fine here as this happens seldom.
+ if (!PersistentAutoDictionary.ContainsWord(DE->GetW()))
+ PersistentAutoDictionary.push_back({DE->GetW(), 1});
+ }
+}
+
+void MutationDispatcher::PrintRecommendedDictionary() {
+ Vector<DictionaryEntry> V;
+ for (auto &DE : PersistentAutoDictionary)
+ if (!ManualDictionary.ContainsWord(DE.GetW()))
+ V.push_back(DE);
+ if (V.empty()) return;
+ Printf("###### Recommended dictionary. ######\n");
+ for (auto &DE: V) {
+ assert(DE.GetW().size());
+ Printf("\"");
+ PrintASCII(DE.GetW(), "\"");
+ Printf(" # Uses: %zd\n", DE.GetUseCount());
+ }
+ Printf("###### End of recommended dictionary. ######\n");
+}
+
+void MutationDispatcher::PrintMutationSequence() {
+ Printf("MS: %zd ", CurrentMutatorSequence.size());
+ for (auto M : CurrentMutatorSequence)
+ Printf("%s-", M.Name);
+ if (!CurrentDictionaryEntrySequence.empty()) {
+ Printf(" DE: ");
+ for (auto DE : CurrentDictionaryEntrySequence) {
+ Printf("\"");
+ PrintASCII(DE->GetW(), "\"-");
+ }
+ }
+}
+
+size_t MutationDispatcher::Mutate(uint8_t *Data, size_t Size, size_t MaxSize) {
+ return MutateImpl(Data, Size, MaxSize, Mutators);
+}
+
+size_t MutationDispatcher::DefaultMutate(uint8_t *Data, size_t Size,
+ size_t MaxSize) {
+ return MutateImpl(Data, Size, MaxSize, DefaultMutators);
+}
+
+// Mutates Data in place, returns new size.
+size_t MutationDispatcher::MutateImpl(uint8_t *Data, size_t Size,
+ size_t MaxSize,
+ Vector<Mutator> &Mutators) {
+ assert(MaxSize > 0);
+ // Some mutations may fail (e.g. can't insert more bytes if Size == MaxSize),
+ // in which case they will return 0.
+ // Try several times before returning un-mutated data.
+ for (int Iter = 0; Iter < 100; Iter++) {
+ auto M = Mutators[Rand(Mutators.size())];
+ size_t NewSize = (this->*(M.Fn))(Data, Size, MaxSize);
+ if (NewSize && NewSize <= MaxSize) {
+ if (Options.OnlyASCII)
+ ToASCII(Data, NewSize);
+ CurrentMutatorSequence.push_back(M);
+ return NewSize;
+ }
+ }
+ *Data = ' ';
+ return 1; // Fallback, should not happen frequently.
+}
+
+// Mask represents the set of Data bytes that are worth mutating.
+size_t MutationDispatcher::MutateWithMask(uint8_t *Data, size_t Size,
+ size_t MaxSize,
+ const Vector<uint8_t> &Mask) {
+ size_t MaskedSize = std::min(Size, Mask.size());
+ // * Copy the worthy bytes into a temporary array T
+ // * Mutate T
+ // * Copy T back.
+ // This is totally unoptimized.
+ auto &T = MutateWithMaskTemp;
+ if (T.size() < Size)
+ T.resize(Size);
+ size_t OneBits = 0;
+ for (size_t I = 0; I < MaskedSize; I++)
+ if (Mask[I])
+ T[OneBits++] = Data[I];
+
+ if (!OneBits) return 0;
+ assert(!T.empty());
+ size_t NewSize = Mutate(T.data(), OneBits, OneBits);
+ assert(NewSize <= OneBits);
+ (void)NewSize;
+ // Even if NewSize < OneBits we still use all OneBits bytes.
+ for (size_t I = 0, J = 0; I < MaskedSize; I++)
+ if (Mask[I])
+ Data[I] = T[J++];
+ return Size;
+}
+
+void MutationDispatcher::AddWordToManualDictionary(const Word &W) {
+ ManualDictionary.push_back(
+ {W, std::numeric_limits<size_t>::max()});
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerMutate.h b/tools/fuzzing/libfuzzer/FuzzerMutate.h
new file mode 100644
index 0000000000..6cbce80276
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerMutate.h
@@ -0,0 +1,156 @@
+//===- FuzzerMutate.h - Internal header for the Fuzzer ----------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::MutationDispatcher
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_MUTATE_H
+#define LLVM_FUZZER_MUTATE_H
+
+#include "FuzzerDefs.h"
+#include "FuzzerDictionary.h"
+#include "FuzzerOptions.h"
+#include "FuzzerRandom.h"
+
+namespace fuzzer {
+
+class MutationDispatcher {
+public:
+ MutationDispatcher(Random &Rand, const FuzzingOptions &Options);
+ ~MutationDispatcher() {}
+ /// Indicate that we are about to start a new sequence of mutations.
+ void StartMutationSequence();
+ /// Print the current sequence of mutations.
+ void PrintMutationSequence();
+ /// Indicate that the current sequence of mutations was successful.
+ void RecordSuccessfulMutationSequence();
+ /// Mutates data by invoking user-provided mutator.
+ size_t Mutate_Custom(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by invoking user-provided crossover.
+ size_t Mutate_CustomCrossOver(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by shuffling bytes.
+ size_t Mutate_ShuffleBytes(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by erasing bytes.
+ size_t Mutate_EraseBytes(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by inserting a byte.
+ size_t Mutate_InsertByte(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by inserting several repeated bytes.
+ size_t Mutate_InsertRepeatedBytes(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by chanding one byte.
+ size_t Mutate_ChangeByte(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by chanding one bit.
+ size_t Mutate_ChangeBit(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Mutates data by copying/inserting a part of data into a different place.
+ size_t Mutate_CopyPart(uint8_t *Data, size_t Size, size_t MaxSize);
+
+ /// Mutates data by adding a word from the manual dictionary.
+ size_t Mutate_AddWordFromManualDictionary(uint8_t *Data, size_t Size,
+ size_t MaxSize);
+
+ /// Mutates data by adding a word from the TORC.
+ size_t Mutate_AddWordFromTORC(uint8_t *Data, size_t Size, size_t MaxSize);
+
+ /// Mutates data by adding a word from the persistent automatic dictionary.
+ size_t Mutate_AddWordFromPersistentAutoDictionary(uint8_t *Data, size_t Size,
+ size_t MaxSize);
+
+ /// Tries to find an ASCII integer in Data, changes it to another ASCII int.
+ size_t Mutate_ChangeASCIIInteger(uint8_t *Data, size_t Size, size_t MaxSize);
+ /// Change a 1-, 2-, 4-, or 8-byte integer in interesting ways.
+ size_t Mutate_ChangeBinaryInteger(uint8_t *Data, size_t Size, size_t MaxSize);
+
+ /// CrossOver Data with CrossOverWith.
+ size_t Mutate_CrossOver(uint8_t *Data, size_t Size, size_t MaxSize);
+
+ /// Applies one of the configured mutations.
+ /// Returns the new size of data which could be up to MaxSize.
+ size_t Mutate(uint8_t *Data, size_t Size, size_t MaxSize);
+
+ /// Applies one of the configured mutations to the bytes of Data
+ /// that have '1' in Mask.
+ /// Mask.size() should be >= Size.
+ size_t MutateWithMask(uint8_t *Data, size_t Size, size_t MaxSize,
+ const Vector<uint8_t> &Mask);
+
+ /// Applies one of the default mutations. Provided as a service
+ /// to mutation authors.
+ size_t DefaultMutate(uint8_t *Data, size_t Size, size_t MaxSize);
+
+ /// Creates a cross-over of two pieces of Data, returns its size.
+ size_t CrossOver(const uint8_t *Data1, size_t Size1, const uint8_t *Data2,
+ size_t Size2, uint8_t *Out, size_t MaxOutSize);
+
+ void AddWordToManualDictionary(const Word &W);
+
+ void PrintRecommendedDictionary();
+
+ void SetCrossOverWith(const Unit *U) { CrossOverWith = U; }
+
+ Random &GetRand() { return Rand; }
+
+ private:
+ struct Mutator {
+ size_t (MutationDispatcher::*Fn)(uint8_t *Data, size_t Size, size_t Max);
+ const char *Name;
+ };
+
+ size_t AddWordFromDictionary(Dictionary &D, uint8_t *Data, size_t Size,
+ size_t MaxSize);
+ size_t MutateImpl(uint8_t *Data, size_t Size, size_t MaxSize,
+ Vector<Mutator> &Mutators);
+
+ size_t InsertPartOf(const uint8_t *From, size_t FromSize, uint8_t *To,
+ size_t ToSize, size_t MaxToSize);
+ size_t CopyPartOf(const uint8_t *From, size_t FromSize, uint8_t *To,
+ size_t ToSize);
+ size_t ApplyDictionaryEntry(uint8_t *Data, size_t Size, size_t MaxSize,
+ DictionaryEntry &DE);
+
+ template <class T>
+ DictionaryEntry MakeDictionaryEntryFromCMP(T Arg1, T Arg2,
+ const uint8_t *Data, size_t Size);
+ DictionaryEntry MakeDictionaryEntryFromCMP(const Word &Arg1, const Word &Arg2,
+ const uint8_t *Data, size_t Size);
+ DictionaryEntry MakeDictionaryEntryFromCMP(const void *Arg1, const void *Arg2,
+ const void *Arg1Mutation,
+ const void *Arg2Mutation,
+ size_t ArgSize,
+ const uint8_t *Data, size_t Size);
+
+ Random &Rand;
+ const FuzzingOptions Options;
+
+ // Dictionary provided by the user via -dict=DICT_FILE.
+ Dictionary ManualDictionary;
+ // Temporary dictionary modified by the fuzzer itself,
+ // recreated periodically.
+ Dictionary TempAutoDictionary;
+ // Persistent dictionary modified by the fuzzer, consists of
+ // entries that led to successful discoveries in the past mutations.
+ Dictionary PersistentAutoDictionary;
+
+ Vector<DictionaryEntry *> CurrentDictionaryEntrySequence;
+
+ static const size_t kCmpDictionaryEntriesDequeSize = 16;
+ DictionaryEntry CmpDictionaryEntriesDeque[kCmpDictionaryEntriesDequeSize];
+ size_t CmpDictionaryEntriesDequeIdx = 0;
+
+ const Unit *CrossOverWith = nullptr;
+ Vector<uint8_t> MutateInPlaceHere;
+ Vector<uint8_t> MutateWithMaskTemp;
+ // CustomCrossOver needs its own buffer as a custom implementation may call
+ // LLVMFuzzerMutate, which in turn may resize MutateInPlaceHere.
+ Vector<uint8_t> CustomCrossOverInPlaceHere;
+
+ Vector<Mutator> Mutators;
+ Vector<Mutator> DefaultMutators;
+ Vector<Mutator> CurrentMutatorSequence;
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_MUTATE_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerOptions.h b/tools/fuzzing/libfuzzer/FuzzerOptions.h
new file mode 100644
index 0000000000..9d975bd61f
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerOptions.h
@@ -0,0 +1,85 @@
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::FuzzingOptions
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_OPTIONS_H
+#define LLVM_FUZZER_OPTIONS_H
+
+#include "FuzzerDefs.h"
+
+namespace fuzzer {
+
+struct FuzzingOptions {
+ int Verbosity = 1;
+ size_t MaxLen = 0;
+ size_t LenControl = 1000;
+ int UnitTimeoutSec = 300;
+ int TimeoutExitCode = 70;
+ int OOMExitCode = 71;
+ int InterruptExitCode = 72;
+ int ErrorExitCode = 77;
+ bool IgnoreTimeouts = true;
+ bool IgnoreOOMs = true;
+ bool IgnoreCrashes = false;
+ int MaxTotalTimeSec = 0;
+ int RssLimitMb = 0;
+ int MallocLimitMb = 0;
+ bool DoCrossOver = true;
+ int MutateDepth = 5;
+ bool ReduceDepth = false;
+ bool UseCounters = false;
+ bool UseMemmem = true;
+ bool UseCmp = false;
+ int UseValueProfile = false;
+ bool Shrink = false;
+ bool ReduceInputs = false;
+ int ReloadIntervalSec = 1;
+ bool ShuffleAtStartUp = true;
+ bool PreferSmall = true;
+ size_t MaxNumberOfRuns = -1L;
+ int ReportSlowUnits = 10;
+ bool OnlyASCII = false;
+ bool Entropic = false;
+ size_t EntropicFeatureFrequencyThreshold = 0xFF;
+ size_t EntropicNumberOfRarestFeatures = 100;
+ std::string OutputCorpus;
+ std::string ArtifactPrefix = "./";
+ std::string ExactArtifactPath;
+ std::string ExitOnSrcPos;
+ std::string ExitOnItem;
+ std::string FocusFunction;
+ std::string DataFlowTrace;
+ std::string CollectDataFlow;
+ std::string FeaturesDir;
+ std::string StopFile;
+ bool SaveArtifacts = true;
+ bool PrintNEW = true; // Print a status line when new units are found;
+ bool PrintNewCovPcs = false;
+ int PrintNewCovFuncs = 0;
+ bool PrintFinalStats = false;
+ bool PrintCorpusStats = false;
+ bool PrintCoverage = false;
+ bool DumpCoverage = false;
+ bool DetectLeaks = true;
+ int PurgeAllocatorIntervalSec = 1;
+ int TraceMalloc = 0;
+ bool HandleAbrt = false;
+ bool HandleBus = false;
+ bool HandleFpe = false;
+ bool HandleIll = false;
+ bool HandleInt = false;
+ bool HandleSegv = false;
+ bool HandleTerm = false;
+ bool HandleXfsz = false;
+ bool HandleUsr1 = false;
+ bool HandleUsr2 = false;
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_OPTIONS_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerPlatform.h b/tools/fuzzing/libfuzzer/FuzzerPlatform.h
new file mode 100644
index 0000000000..8befdb882c
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerPlatform.h
@@ -0,0 +1,163 @@
+//===-- FuzzerPlatform.h --------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Common platform macros.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_PLATFORM_H
+#define LLVM_FUZZER_PLATFORM_H
+
+// Platform detection.
+#ifdef __linux__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 1
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif __APPLE__
+#define LIBFUZZER_APPLE 1
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif __NetBSD__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 1
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif __FreeBSD__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 1
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif __OpenBSD__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 1
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif _WIN32
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 1
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif __Fuchsia__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 1
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 0
+#elif __EMSCRIPTEN__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
+#define LIBFUZZER_EMSCRIPTEN 1
+#else
+#error "Support for your platform has not been implemented"
+#endif
+
+#if defined(_MSC_VER) && !defined(__clang__)
+// MSVC compiler is being used.
+#define LIBFUZZER_MSVC 1
+#else
+#define LIBFUZZER_MSVC 0
+#endif
+
+#ifndef __has_attribute
+#define __has_attribute(x) 0
+#endif
+
+#define LIBFUZZER_POSIX \
+ (LIBFUZZER_APPLE || LIBFUZZER_LINUX || LIBFUZZER_NETBSD || \
+ LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD || LIBFUZZER_EMSCRIPTEN)
+
+#ifdef __x86_64
+#if __has_attribute(target)
+#define ATTRIBUTE_TARGET_POPCNT __attribute__((target("popcnt")))
+#else
+#define ATTRIBUTE_TARGET_POPCNT
+#endif
+#else
+#define ATTRIBUTE_TARGET_POPCNT
+#endif
+
+#ifdef __clang__ // avoid gcc warning.
+#if __has_attribute(no_sanitize)
+#define ATTRIBUTE_NO_SANITIZE_MEMORY __attribute__((no_sanitize("memory")))
+#else
+#define ATTRIBUTE_NO_SANITIZE_MEMORY
+#endif
+#define ALWAYS_INLINE __attribute__((always_inline))
+#else
+#define ATTRIBUTE_NO_SANITIZE_MEMORY
+#define ALWAYS_INLINE
+#endif // __clang__
+
+#if LIBFUZZER_WINDOWS
+#define ATTRIBUTE_NO_SANITIZE_ADDRESS
+#else
+#define ATTRIBUTE_NO_SANITIZE_ADDRESS __attribute__((no_sanitize_address))
+#endif
+
+#if LIBFUZZER_WINDOWS
+#define ATTRIBUTE_ALIGNED(X) __declspec(align(X))
+#define ATTRIBUTE_INTERFACE __declspec(dllexport)
+// This is used for __sancov_lowest_stack which is needed for
+// -fsanitize-coverage=stack-depth. That feature is not yet available on
+// Windows, so make the symbol static to avoid linking errors.
+#define ATTRIBUTES_INTERFACE_TLS_INITIAL_EXEC static
+#define ATTRIBUTE_NOINLINE __declspec(noinline)
+#else
+#define ATTRIBUTE_ALIGNED(X) __attribute__((aligned(X)))
+#define ATTRIBUTE_INTERFACE __attribute__((visibility("default")))
+#define ATTRIBUTES_INTERFACE_TLS_INITIAL_EXEC \
+ ATTRIBUTE_INTERFACE __attribute__((tls_model("initial-exec"))) thread_local
+
+#define ATTRIBUTE_NOINLINE __attribute__((noinline))
+#endif
+
+#if defined(__has_feature)
+#if __has_feature(address_sanitizer)
+#define ATTRIBUTE_NO_SANITIZE_ALL ATTRIBUTE_NO_SANITIZE_ADDRESS
+#elif __has_feature(memory_sanitizer)
+#define ATTRIBUTE_NO_SANITIZE_ALL ATTRIBUTE_NO_SANITIZE_MEMORY
+#else
+#define ATTRIBUTE_NO_SANITIZE_ALL
+#endif
+#else
+#define ATTRIBUTE_NO_SANITIZE_ALL
+#endif
+
+#endif // LLVM_FUZZER_PLATFORM_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerRandom.h b/tools/fuzzing/libfuzzer/FuzzerRandom.h
new file mode 100644
index 0000000000..659283eee2
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerRandom.h
@@ -0,0 +1,38 @@
+//===- FuzzerRandom.h - Internal header for the Fuzzer ----------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::Random
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_RANDOM_H
+#define LLVM_FUZZER_RANDOM_H
+
+#include <random>
+
+namespace fuzzer {
+class Random : public std::minstd_rand {
+ public:
+ Random(unsigned int seed) : std::minstd_rand(seed) {}
+ result_type operator()() { return this->std::minstd_rand::operator()(); }
+ size_t Rand() { return this->operator()(); }
+ size_t RandBool() { return Rand() % 2; }
+ size_t SkewTowardsLast(size_t n) {
+ size_t T = this->operator()(n * n);
+ size_t Res = sqrt(T);
+ return Res;
+ }
+ size_t operator()(size_t n) { return n ? Rand() % n : 0; }
+ intptr_t operator()(intptr_t From, intptr_t To) {
+ assert(From < To);
+ intptr_t RangeSize = To - From + 1;
+ return operator()(RangeSize) + From;
+ }
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_RANDOM_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerSHA1.cpp b/tools/fuzzing/libfuzzer/FuzzerSHA1.cpp
new file mode 100644
index 0000000000..2005dc7003
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerSHA1.cpp
@@ -0,0 +1,223 @@
+//===- FuzzerSHA1.h - Private copy of the SHA1 implementation ---*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// This code is taken from public domain
+// (http://oauth.googlecode.com/svn/code/c/liboauth/src/sha1.c)
+// and modified by adding anonymous namespace, adding an interface
+// function fuzzer::ComputeSHA1() and removing unnecessary code.
+//
+// lib/Fuzzer can not use SHA1 implementation from openssl because
+// openssl may not be available and because we may be fuzzing openssl itself.
+// For the same reason we do not want to depend on SHA1 from LLVM tree.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerSHA1.h"
+#include "FuzzerDefs.h"
+#include "FuzzerPlatform.h"
+
+/* This code is public-domain - it is based on libcrypt
+ * placed in the public domain by Wei Dai and other contributors.
+ */
+
+#include <iomanip>
+#include <sstream>
+#include <stdint.h>
+#include <string.h>
+
+namespace { // Added for LibFuzzer
+
+#ifdef __BIG_ENDIAN__
+# define SHA_BIG_ENDIAN
+// Windows is always little endian and MSVC doesn't have <endian.h>
+#elif defined __LITTLE_ENDIAN__ || LIBFUZZER_WINDOWS
+/* override */
+#elif defined __BYTE_ORDER
+# if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define SHA_BIG_ENDIAN
+# endif
+#else // ! defined __LITTLE_ENDIAN__
+# include <endian.h> // machine/endian.h
+# if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define SHA_BIG_ENDIAN
+# endif
+#endif
+
+
+/* header */
+
+#define HASH_LENGTH 20
+#define BLOCK_LENGTH 64
+
+typedef struct sha1nfo {
+ uint32_t buffer[BLOCK_LENGTH/4];
+ uint32_t state[HASH_LENGTH/4];
+ uint32_t byteCount;
+ uint8_t bufferOffset;
+ uint8_t keyBuffer[BLOCK_LENGTH];
+ uint8_t innerHash[HASH_LENGTH];
+} sha1nfo;
+
+/* public API - prototypes - TODO: doxygen*/
+
+/**
+ */
+void sha1_init(sha1nfo *s);
+/**
+ */
+void sha1_writebyte(sha1nfo *s, uint8_t data);
+/**
+ */
+void sha1_write(sha1nfo *s, const char *data, size_t len);
+/**
+ */
+uint8_t* sha1_result(sha1nfo *s);
+
+
+/* code */
+#define SHA1_K0 0x5a827999
+#define SHA1_K20 0x6ed9eba1
+#define SHA1_K40 0x8f1bbcdc
+#define SHA1_K60 0xca62c1d6
+
+void sha1_init(sha1nfo *s) {
+ s->state[0] = 0x67452301;
+ s->state[1] = 0xefcdab89;
+ s->state[2] = 0x98badcfe;
+ s->state[3] = 0x10325476;
+ s->state[4] = 0xc3d2e1f0;
+ s->byteCount = 0;
+ s->bufferOffset = 0;
+}
+
+uint32_t sha1_rol32(uint32_t number, uint8_t bits) {
+ return ((number << bits) | (number >> (32-bits)));
+}
+
+void sha1_hashBlock(sha1nfo *s) {
+ uint8_t i;
+ uint32_t a,b,c,d,e,t;
+
+ a=s->state[0];
+ b=s->state[1];
+ c=s->state[2];
+ d=s->state[3];
+ e=s->state[4];
+ for (i=0; i<80; i++) {
+ if (i>=16) {
+ t = s->buffer[(i+13)&15] ^ s->buffer[(i+8)&15] ^ s->buffer[(i+2)&15] ^ s->buffer[i&15];
+ s->buffer[i&15] = sha1_rol32(t,1);
+ }
+ if (i<20) {
+ t = (d ^ (b & (c ^ d))) + SHA1_K0;
+ } else if (i<40) {
+ t = (b ^ c ^ d) + SHA1_K20;
+ } else if (i<60) {
+ t = ((b & c) | (d & (b | c))) + SHA1_K40;
+ } else {
+ t = (b ^ c ^ d) + SHA1_K60;
+ }
+ t+=sha1_rol32(a,5) + e + s->buffer[i&15];
+ e=d;
+ d=c;
+ c=sha1_rol32(b,30);
+ b=a;
+ a=t;
+ }
+ s->state[0] += a;
+ s->state[1] += b;
+ s->state[2] += c;
+ s->state[3] += d;
+ s->state[4] += e;
+}
+
+void sha1_addUncounted(sha1nfo *s, uint8_t data) {
+ uint8_t * const b = (uint8_t*) s->buffer;
+#ifdef SHA_BIG_ENDIAN
+ b[s->bufferOffset] = data;
+#else
+ b[s->bufferOffset ^ 3] = data;
+#endif
+ s->bufferOffset++;
+ if (s->bufferOffset == BLOCK_LENGTH) {
+ sha1_hashBlock(s);
+ s->bufferOffset = 0;
+ }
+}
+
+void sha1_writebyte(sha1nfo *s, uint8_t data) {
+ ++s->byteCount;
+ sha1_addUncounted(s, data);
+}
+
+void sha1_write(sha1nfo *s, const char *data, size_t len) {
+ for (;len--;) sha1_writebyte(s, (uint8_t) *data++);
+}
+
+void sha1_pad(sha1nfo *s) {
+ // Implement SHA-1 padding (fips180-2 §5.1.1)
+
+ // Pad with 0x80 followed by 0x00 until the end of the block
+ sha1_addUncounted(s, 0x80);
+ while (s->bufferOffset != 56) sha1_addUncounted(s, 0x00);
+
+ // Append length in the last 8 bytes
+ sha1_addUncounted(s, 0); // We're only using 32 bit lengths
+ sha1_addUncounted(s, 0); // But SHA-1 supports 64 bit lengths
+ sha1_addUncounted(s, 0); // So zero pad the top bits
+ sha1_addUncounted(s, s->byteCount >> 29); // Shifting to multiply by 8
+ sha1_addUncounted(s, s->byteCount >> 21); // as SHA-1 supports bitstreams as well as
+ sha1_addUncounted(s, s->byteCount >> 13); // byte.
+ sha1_addUncounted(s, s->byteCount >> 5);
+ sha1_addUncounted(s, s->byteCount << 3);
+}
+
+uint8_t* sha1_result(sha1nfo *s) {
+ // Pad to complete the last block
+ sha1_pad(s);
+
+#ifndef SHA_BIG_ENDIAN
+ // Swap byte order back
+ int i;
+ for (i=0; i<5; i++) {
+ s->state[i]=
+ (((s->state[i])<<24)& 0xff000000)
+ | (((s->state[i])<<8) & 0x00ff0000)
+ | (((s->state[i])>>8) & 0x0000ff00)
+ | (((s->state[i])>>24)& 0x000000ff);
+ }
+#endif
+
+ // Return pointer to hash (20 characters)
+ return (uint8_t*) s->state;
+}
+
+} // namespace; Added for LibFuzzer
+
+namespace fuzzer {
+
+// The rest is added for LibFuzzer
+void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out) {
+ sha1nfo s;
+ sha1_init(&s);
+ sha1_write(&s, (const char*)Data, Len);
+ memcpy(Out, sha1_result(&s), HASH_LENGTH);
+}
+
+std::string Sha1ToString(const uint8_t Sha1[kSHA1NumBytes]) {
+ std::stringstream SS;
+ for (int i = 0; i < kSHA1NumBytes; i++)
+ SS << std::hex << std::setfill('0') << std::setw(2) << (unsigned)Sha1[i];
+ return SS.str();
+}
+
+std::string Hash(const Unit &U) {
+ uint8_t Hash[kSHA1NumBytes];
+ ComputeSHA1(U.data(), U.size(), Hash);
+ return Sha1ToString(Hash);
+}
+
+}
diff --git a/tools/fuzzing/libfuzzer/FuzzerSHA1.h b/tools/fuzzing/libfuzzer/FuzzerSHA1.h
new file mode 100644
index 0000000000..05cbacda87
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerSHA1.h
@@ -0,0 +1,32 @@
+//===- FuzzerSHA1.h - Internal header for the SHA1 utils --------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// SHA1 utils.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_SHA1_H
+#define LLVM_FUZZER_SHA1_H
+
+#include "FuzzerDefs.h"
+#include <cstddef>
+#include <stdint.h>
+
+namespace fuzzer {
+
+// Private copy of SHA1 implementation.
+static const int kSHA1NumBytes = 20;
+
+// Computes SHA1 hash of 'Len' bytes in 'Data', writes kSHA1NumBytes to 'Out'.
+void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out);
+
+std::string Sha1ToString(const uint8_t Sha1[kSHA1NumBytes]);
+
+std::string Hash(const Unit &U);
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_SHA1_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp b/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp
new file mode 100644
index 0000000000..fbceda39bc
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp
@@ -0,0 +1,657 @@
+//===- FuzzerTracePC.cpp - PC tracing--------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Trace PCs.
+// This module implements __sanitizer_cov_trace_pc_guard[_init],
+// the callback required for -fsanitize-coverage=trace-pc-guard instrumentation.
+//
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerTracePC.h"
+#include "FuzzerBuiltins.h"
+#include "FuzzerBuiltinsMsvc.h"
+#include "FuzzerCorpus.h"
+#include "FuzzerDefs.h"
+#include "FuzzerDictionary.h"
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include "FuzzerPlatform.h"
+#include "FuzzerUtil.h"
+#include "FuzzerValueBitMap.h"
+#include <set>
+
+// Used by -fsanitize-coverage=stack-depth to track stack depth
+ATTRIBUTES_INTERFACE_TLS_INITIAL_EXEC uintptr_t __sancov_lowest_stack;
+
+namespace fuzzer {
+
+TracePC TPC;
+
+size_t TracePC::GetTotalPCCoverage() {
+ return ObservedPCs.size();
+}
+
+
+void TracePC::HandleInline8bitCountersInit(uint8_t *Start, uint8_t *Stop) {
+ if (Start == Stop) return;
+ if (NumModules &&
+ Modules[NumModules - 1].Start() == Start)
+ return;
+ assert(NumModules <
+ sizeof(Modules) / sizeof(Modules[0]));
+ auto &M = Modules[NumModules++];
+ uint8_t *AlignedStart = RoundUpByPage(Start);
+ uint8_t *AlignedStop = RoundDownByPage(Stop);
+ size_t NumFullPages = AlignedStop > AlignedStart ?
+ (AlignedStop - AlignedStart) / PageSize() : 0;
+ bool NeedFirst = Start < AlignedStart || !NumFullPages;
+ bool NeedLast = Stop > AlignedStop && AlignedStop >= AlignedStart;
+ M.NumRegions = NumFullPages + NeedFirst + NeedLast;;
+ assert(M.NumRegions > 0);
+ M.Regions = new Module::Region[M.NumRegions];
+ assert(M.Regions);
+ size_t R = 0;
+ if (NeedFirst)
+ M.Regions[R++] = {Start, std::min(Stop, AlignedStart), true, false};
+ for (uint8_t *P = AlignedStart; P < AlignedStop; P += PageSize())
+ M.Regions[R++] = {P, P + PageSize(), true, true};
+ if (NeedLast)
+ M.Regions[R++] = {AlignedStop, Stop, true, false};
+ assert(R == M.NumRegions);
+ assert(M.Size() == (size_t)(Stop - Start));
+ assert(M.Stop() == Stop);
+ assert(M.Start() == Start);
+ NumInline8bitCounters += M.Size();
+}
+
+void TracePC::HandlePCsInit(const uintptr_t *Start, const uintptr_t *Stop) {
+ const PCTableEntry *B = reinterpret_cast<const PCTableEntry *>(Start);
+ const PCTableEntry *E = reinterpret_cast<const PCTableEntry *>(Stop);
+ if (NumPCTables && ModulePCTable[NumPCTables - 1].Start == B) return;
+ assert(NumPCTables < sizeof(ModulePCTable) / sizeof(ModulePCTable[0]));
+ ModulePCTable[NumPCTables++] = {B, E};
+ NumPCsInPCTables += E - B;
+}
+
+void TracePC::PrintModuleInfo() {
+ if (NumModules) {
+ Printf("INFO: Loaded %zd modules (%zd inline 8-bit counters): ",
+ NumModules, NumInline8bitCounters);
+ for (size_t i = 0; i < NumModules; i++)
+ Printf("%zd [%p, %p), ", Modules[i].Size(), Modules[i].Start(),
+ Modules[i].Stop());
+ Printf("\n");
+ }
+ if (NumPCTables) {
+ Printf("INFO: Loaded %zd PC tables (%zd PCs): ", NumPCTables,
+ NumPCsInPCTables);
+ for (size_t i = 0; i < NumPCTables; i++) {
+ Printf("%zd [%p,%p), ", ModulePCTable[i].Stop - ModulePCTable[i].Start,
+ ModulePCTable[i].Start, ModulePCTable[i].Stop);
+ }
+ Printf("\n");
+
+ if (NumInline8bitCounters && NumInline8bitCounters != NumPCsInPCTables) {
+ Printf("ERROR: The size of coverage PC tables does not match the\n"
+ "number of instrumented PCs. This might be a compiler bug,\n"
+ "please contact the libFuzzer developers.\n"
+ "Also check https://bugs.llvm.org/show_bug.cgi?id=34636\n"
+ "for possible workarounds (tl;dr: don't use the old GNU ld)\n");
+ _Exit(1);
+ }
+ }
+ if (size_t NumExtraCounters = ExtraCountersEnd() - ExtraCountersBegin())
+ Printf("INFO: %zd Extra Counters\n", NumExtraCounters);
+}
+
+ATTRIBUTE_NO_SANITIZE_ALL
+void TracePC::HandleCallerCallee(uintptr_t Caller, uintptr_t Callee) {
+ const uintptr_t kBits = 12;
+ const uintptr_t kMask = (1 << kBits) - 1;
+ uintptr_t Idx = (Caller & kMask) | ((Callee & kMask) << kBits);
+ ValueProfileMap.AddValueModPrime(Idx);
+}
+
+/// \return the address of the previous instruction.
+/// Note: the logic is copied from `sanitizer_common/sanitizer_stacktrace.h`
+inline ALWAYS_INLINE uintptr_t GetPreviousInstructionPc(uintptr_t PC) {
+#if defined(__arm__)
+ // T32 (Thumb) branch instructions might be 16 or 32 bit long,
+ // so we return (pc-2) in that case in order to be safe.
+ // For A32 mode we return (pc-4) because all instructions are 32 bit long.
+ return (PC - 3) & (~1);
+#elif defined(__powerpc__) || defined(__powerpc64__) || defined(__aarch64__)
+ // PCs are always 4 byte aligned.
+ return PC - 4;
+#elif defined(__sparc__) || defined(__mips__)
+ return PC - 8;
+#else
+ return PC - 1;
+#endif
+}
+
+/// \return the address of the next instruction.
+/// Note: the logic is copied from `sanitizer_common/sanitizer_stacktrace.cpp`
+ALWAYS_INLINE uintptr_t TracePC::GetNextInstructionPc(uintptr_t PC) {
+#if defined(__mips__)
+ return PC + 8;
+#elif defined(__powerpc__) || defined(__sparc__) || defined(__arm__) || \
+ defined(__aarch64__)
+ return PC + 4;
+#else
+ return PC + 1;
+#endif
+}
+
+void TracePC::UpdateObservedPCs() {
+ Vector<uintptr_t> CoveredFuncs;
+ auto ObservePC = [&](const PCTableEntry *TE) {
+ if (ObservedPCs.insert(TE).second && DoPrintNewPCs) {
+ PrintPC("\tNEW_PC: %p %F %L", "\tNEW_PC: %p",
+ GetNextInstructionPc(TE->PC));
+ Printf("\n");
+ }
+ };
+
+ auto Observe = [&](const PCTableEntry *TE) {
+ if (PcIsFuncEntry(TE))
+ if (++ObservedFuncs[TE->PC] == 1 && NumPrintNewFuncs)
+ CoveredFuncs.push_back(TE->PC);
+ ObservePC(TE);
+ };
+
+ if (NumPCsInPCTables) {
+ if (NumInline8bitCounters == NumPCsInPCTables) {
+ for (size_t i = 0; i < NumModules; i++) {
+ auto &M = Modules[i];
+ assert(M.Size() ==
+ (size_t)(ModulePCTable[i].Stop - ModulePCTable[i].Start));
+ for (size_t r = 0; r < M.NumRegions; r++) {
+ auto &R = M.Regions[r];
+ if (!R.Enabled) continue;
+ for (uint8_t *P = R.Start; P < R.Stop; P++)
+ if (*P)
+ Observe(&ModulePCTable[i].Start[M.Idx(P)]);
+ }
+ }
+ }
+ }
+
+ for (size_t i = 0, N = Min(CoveredFuncs.size(), NumPrintNewFuncs); i < N;
+ i++) {
+ Printf("\tNEW_FUNC[%zd/%zd]: ", i + 1, CoveredFuncs.size());
+ PrintPC("%p %F %L", "%p", GetNextInstructionPc(CoveredFuncs[i]));
+ Printf("\n");
+ }
+}
+
+uintptr_t TracePC::PCTableEntryIdx(const PCTableEntry *TE) {
+ size_t TotalTEs = 0;
+ for (size_t i = 0; i < NumPCTables; i++) {
+ auto &M = ModulePCTable[i];
+ if (TE >= M.Start && TE < M.Stop)
+ return TotalTEs + TE - M.Start;
+ TotalTEs += M.Stop - M.Start;
+ }
+ assert(0);
+ return 0;
+}
+
+const TracePC::PCTableEntry *TracePC::PCTableEntryByIdx(uintptr_t Idx) {
+ for (size_t i = 0; i < NumPCTables; i++) {
+ auto &M = ModulePCTable[i];
+ size_t Size = M.Stop - M.Start;
+ if (Idx < Size) return &M.Start[Idx];
+ Idx -= Size;
+ }
+ return nullptr;
+}
+
+static std::string GetModuleName(uintptr_t PC) {
+ char ModulePathRaw[4096] = ""; // What's PATH_MAX in portable C++?
+ void *OffsetRaw = nullptr;
+ if (!EF->__sanitizer_get_module_and_offset_for_pc(
+ reinterpret_cast<void *>(PC), ModulePathRaw,
+ sizeof(ModulePathRaw), &OffsetRaw))
+ return "";
+ return ModulePathRaw;
+}
+
+template<class CallBack>
+void TracePC::IterateCoveredFunctions(CallBack CB) {
+ for (size_t i = 0; i < NumPCTables; i++) {
+ auto &M = ModulePCTable[i];
+ assert(M.Start < M.Stop);
+ auto ModuleName = GetModuleName(M.Start->PC);
+ for (auto NextFE = M.Start; NextFE < M.Stop; ) {
+ auto FE = NextFE;
+ assert(PcIsFuncEntry(FE) && "Not a function entry point");
+ do {
+ NextFE++;
+ } while (NextFE < M.Stop && !(PcIsFuncEntry(NextFE)));
+ CB(FE, NextFE, ObservedFuncs[FE->PC]);
+ }
+ }
+}
+
+int TracePC::SetFocusFunction(const std::string &FuncName) {
+ // This function should be called once.
+ assert(!FocusFunctionCounterPtr);
+ // "auto" is not a valid function name. If this function is called with "auto"
+ // that means the auto focus functionality failed.
+ if (FuncName.empty() || FuncName == "auto")
+ return 0;
+ for (size_t M = 0; M < NumModules; M++) {
+ auto &PCTE = ModulePCTable[M];
+ size_t N = PCTE.Stop - PCTE.Start;
+ for (size_t I = 0; I < N; I++) {
+ if (!(PcIsFuncEntry(&PCTE.Start[I]))) continue; // not a function entry.
+ auto Name = DescribePC("%F", GetNextInstructionPc(PCTE.Start[I].PC));
+ if (Name[0] == 'i' && Name[1] == 'n' && Name[2] == ' ')
+ Name = Name.substr(3, std::string::npos);
+ if (FuncName != Name) continue;
+ Printf("INFO: Focus function is set to '%s'\n", Name.c_str());
+ FocusFunctionCounterPtr = Modules[M].Start() + I;
+ return 0;
+ }
+ }
+
+ Printf("ERROR: Failed to set focus function. Make sure the function name is "
+ "valid (%s) and symbolization is enabled.\n", FuncName.c_str());
+ return 1;
+}
+
+bool TracePC::ObservedFocusFunction() {
+ return FocusFunctionCounterPtr && *FocusFunctionCounterPtr;
+}
+
+void TracePC::PrintCoverage() {
+ if (!EF->__sanitizer_symbolize_pc ||
+ !EF->__sanitizer_get_module_and_offset_for_pc) {
+ Printf("INFO: __sanitizer_symbolize_pc or "
+ "__sanitizer_get_module_and_offset_for_pc is not available,"
+ " not printing coverage\n");
+ return;
+ }
+ Printf("COVERAGE:\n");
+ auto CoveredFunctionCallback = [&](const PCTableEntry *First,
+ const PCTableEntry *Last,
+ uintptr_t Counter) {
+ assert(First < Last);
+ auto VisualizePC = GetNextInstructionPc(First->PC);
+ std::string FileStr = DescribePC("%s", VisualizePC);
+ if (!IsInterestingCoverageFile(FileStr))
+ return;
+ std::string FunctionStr = DescribePC("%F", VisualizePC);
+ if (FunctionStr.find("in ") == 0)
+ FunctionStr = FunctionStr.substr(3);
+ std::string LineStr = DescribePC("%l", VisualizePC);
+ size_t NumEdges = Last - First;
+ Vector<uintptr_t> UncoveredPCs;
+ for (auto TE = First; TE < Last; TE++)
+ if (!ObservedPCs.count(TE))
+ UncoveredPCs.push_back(TE->PC);
+ Printf("%sCOVERED_FUNC: hits: %zd", Counter ? "" : "UN", Counter);
+ Printf(" edges: %zd/%zd", NumEdges - UncoveredPCs.size(), NumEdges);
+ Printf(" %s %s:%s\n", FunctionStr.c_str(), FileStr.c_str(),
+ LineStr.c_str());
+ if (Counter)
+ for (auto PC : UncoveredPCs)
+ Printf(" UNCOVERED_PC: %s\n",
+ DescribePC("%s:%l", GetNextInstructionPc(PC)).c_str());
+ };
+
+ IterateCoveredFunctions(CoveredFunctionCallback);
+}
+
+// Value profile.
+// We keep track of various values that affect control flow.
+// These values are inserted into a bit-set-based hash map.
+// Every new bit in the map is treated as a new coverage.
+//
+// For memcmp/strcmp/etc the interesting value is the length of the common
+// prefix of the parameters.
+// For cmp instructions the interesting value is a XOR of the parameters.
+// The interesting value is mixed up with the PC and is then added to the map.
+
+ATTRIBUTE_NO_SANITIZE_ALL
+void TracePC::AddValueForMemcmp(void *caller_pc, const void *s1, const void *s2,
+ size_t n, bool StopAtZero) {
+ if (!n) return;
+ size_t Len = std::min(n, Word::GetMaxSize());
+ const uint8_t *A1 = reinterpret_cast<const uint8_t *>(s1);
+ const uint8_t *A2 = reinterpret_cast<const uint8_t *>(s2);
+ uint8_t B1[Word::kMaxSize];
+ uint8_t B2[Word::kMaxSize];
+ // Copy the data into locals in this non-msan-instrumented function
+ // to avoid msan complaining further.
+ size_t Hash = 0; // Compute some simple hash of both strings.
+ for (size_t i = 0; i < Len; i++) {
+ B1[i] = A1[i];
+ B2[i] = A2[i];
+ size_t T = B1[i];
+ Hash ^= (T << 8) | B2[i];
+ }
+ size_t I = 0;
+ uint8_t HammingDistance = 0;
+ for (; I < Len; I++) {
+ if (B1[I] != B2[I] || (StopAtZero && B1[I] == 0)) {
+ HammingDistance = Popcountll(B1[I] ^ B2[I]);
+ break;
+ }
+ }
+ size_t PC = reinterpret_cast<size_t>(caller_pc);
+ size_t Idx = (PC & 4095) | (I << 12);
+ Idx += HammingDistance;
+ ValueProfileMap.AddValue(Idx);
+ TORCW.Insert(Idx ^ Hash, Word(B1, Len), Word(B2, Len));
+}
+
+template <class T>
+ATTRIBUTE_TARGET_POPCNT ALWAYS_INLINE
+ATTRIBUTE_NO_SANITIZE_ALL
+void TracePC::HandleCmp(uintptr_t PC, T Arg1, T Arg2) {
+ uint64_t ArgXor = Arg1 ^ Arg2;
+ if (sizeof(T) == 4)
+ TORC4.Insert(ArgXor, Arg1, Arg2);
+ else if (sizeof(T) == 8)
+ TORC8.Insert(ArgXor, Arg1, Arg2);
+ uint64_t HammingDistance = Popcountll(ArgXor); // [0,64]
+ uint64_t AbsoluteDistance = (Arg1 == Arg2 ? 0 : Clzll(Arg1 - Arg2) + 1);
+ ValueProfileMap.AddValue(PC * 128 + HammingDistance);
+ ValueProfileMap.AddValue(PC * 128 + 64 + AbsoluteDistance);
+}
+
+static size_t InternalStrnlen(const char *S, size_t MaxLen) {
+ size_t Len = 0;
+ for (; Len < MaxLen && S[Len]; Len++) {}
+ return Len;
+}
+
+// Finds min of (strlen(S1), strlen(S2)).
+// Needed bacause one of these strings may actually be non-zero terminated.
+static size_t InternalStrnlen2(const char *S1, const char *S2) {
+ size_t Len = 0;
+ for (; S1[Len] && S2[Len]; Len++) {}
+ return Len;
+}
+
+void TracePC::ClearInlineCounters() {
+ IterateCounterRegions([](const Module::Region &R){
+ if (R.Enabled)
+ memset(R.Start, 0, R.Stop - R.Start);
+ });
+}
+
+ATTRIBUTE_NO_SANITIZE_ALL
+void TracePC::RecordInitialStack() {
+ int stack;
+ __sancov_lowest_stack = InitialStack = reinterpret_cast<uintptr_t>(&stack);
+}
+
+uintptr_t TracePC::GetMaxStackOffset() const {
+ return InitialStack - __sancov_lowest_stack; // Stack grows down
+}
+
+void WarnAboutDeprecatedInstrumentation(const char *flag) {
+ // Use RawPrint because Printf cannot be used on Windows before OutputFile is
+ // initialized.
+ RawPrint(flag);
+ RawPrint(
+ " is no longer supported by libFuzzer.\n"
+ "Please either migrate to a compiler that supports -fsanitize=fuzzer\n"
+ "or use an older version of libFuzzer\n");
+ exit(1);
+}
+
+} // namespace fuzzer
+
+extern "C" {
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+void __sanitizer_cov_trace_pc_guard(uint32_t *Guard) {
+ fuzzer::WarnAboutDeprecatedInstrumentation(
+ "-fsanitize-coverage=trace-pc-guard");
+}
+
+// Best-effort support for -fsanitize-coverage=trace-pc, which is available
+// in both Clang and GCC.
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+void __sanitizer_cov_trace_pc() {
+ fuzzer::WarnAboutDeprecatedInstrumentation("-fsanitize-coverage=trace-pc");
+}
+
+ATTRIBUTE_INTERFACE
+void __sanitizer_cov_trace_pc_guard_init(uint32_t *Start, uint32_t *Stop) {
+ fuzzer::WarnAboutDeprecatedInstrumentation(
+ "-fsanitize-coverage=trace-pc-guard");
+}
+
+ATTRIBUTE_INTERFACE
+void __sanitizer_cov_8bit_counters_init(uint8_t *Start, uint8_t *Stop) {
+ fuzzer::TPC.HandleInline8bitCountersInit(Start, Stop);
+}
+
+ATTRIBUTE_INTERFACE
+void __sanitizer_cov_pcs_init(const uintptr_t *pcs_beg,
+ const uintptr_t *pcs_end) {
+ fuzzer::TPC.HandlePCsInit(pcs_beg, pcs_end);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+void __sanitizer_cov_trace_pc_indir(uintptr_t Callee) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCallerCallee(PC, Callee);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_cmp8(uint64_t Arg1, uint64_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+// Now the __sanitizer_cov_trace_const_cmp[1248] callbacks just mimic
+// the behaviour of __sanitizer_cov_trace_cmp[1248] ones. This, however,
+// should be changed later to make full use of instrumentation.
+void __sanitizer_cov_trace_const_cmp8(uint64_t Arg1, uint64_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_cmp4(uint32_t Arg1, uint32_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_const_cmp4(uint32_t Arg1, uint32_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_cmp2(uint16_t Arg1, uint16_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_const_cmp2(uint16_t Arg1, uint16_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_cmp1(uint8_t Arg1, uint8_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_const_cmp1(uint8_t Arg1, uint8_t Arg2) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_switch(uint64_t Val, uint64_t *Cases) {
+ uint64_t N = Cases[0];
+ uint64_t ValSizeInBits = Cases[1];
+ uint64_t *Vals = Cases + 2;
+ // Skip the most common and the most boring case: all switch values are small.
+ // We may want to skip this at compile-time, but it will make the
+ // instrumentation less general.
+ if (Vals[N - 1] < 256)
+ return;
+ // Also skip small inputs values, they won't give good signal.
+ if (Val < 256)
+ return;
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ size_t i;
+ uint64_t Smaller = 0;
+ uint64_t Larger = ~(uint64_t)0;
+ // Find two switch values such that Smaller < Val < Larger.
+ // Use 0 and 0xfff..f as the defaults.
+ for (i = 0; i < N; i++) {
+ if (Val < Vals[i]) {
+ Larger = Vals[i];
+ break;
+ }
+ if (Val > Vals[i]) Smaller = Vals[i];
+ }
+
+ // Apply HandleCmp to {Val,Smaller} and {Val, Larger},
+ // use i as the PC modifier for HandleCmp.
+ if (ValSizeInBits == 16) {
+ fuzzer::TPC.HandleCmp(PC + 2 * i, static_cast<uint16_t>(Val),
+ (uint16_t)(Smaller));
+ fuzzer::TPC.HandleCmp(PC + 2 * i + 1, static_cast<uint16_t>(Val),
+ (uint16_t)(Larger));
+ } else if (ValSizeInBits == 32) {
+ fuzzer::TPC.HandleCmp(PC + 2 * i, static_cast<uint32_t>(Val),
+ (uint32_t)(Smaller));
+ fuzzer::TPC.HandleCmp(PC + 2 * i + 1, static_cast<uint32_t>(Val),
+ (uint32_t)(Larger));
+ } else {
+ fuzzer::TPC.HandleCmp(PC + 2*i, Val, Smaller);
+ fuzzer::TPC.HandleCmp(PC + 2*i + 1, Val, Larger);
+ }
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_div4(uint32_t Val) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Val, (uint32_t)0);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_div8(uint64_t Val) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Val, (uint64_t)0);
+}
+
+ATTRIBUTE_INTERFACE
+ATTRIBUTE_NO_SANITIZE_ALL
+ATTRIBUTE_TARGET_POPCNT
+void __sanitizer_cov_trace_gep(uintptr_t Idx) {
+ uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
+ fuzzer::TPC.HandleCmp(PC, Idx, (uintptr_t)0);
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_memcmp(void *caller_pc, const void *s1,
+ const void *s2, size_t n, int result) {
+ if (!fuzzer::RunningUserCallback) return;
+ if (result == 0) return; // No reason to mutate.
+ if (n <= 1) return; // Not interesting.
+ fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n, /*StopAtZero*/false);
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_strncmp(void *caller_pc, const char *s1,
+ const char *s2, size_t n, int result) {
+ if (!fuzzer::RunningUserCallback) return;
+ if (result == 0) return; // No reason to mutate.
+ size_t Len1 = fuzzer::InternalStrnlen(s1, n);
+ size_t Len2 = fuzzer::InternalStrnlen(s2, n);
+ n = std::min(n, Len1);
+ n = std::min(n, Len2);
+ if (n <= 1) return; // Not interesting.
+ fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n, /*StopAtZero*/true);
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_strcmp(void *caller_pc, const char *s1,
+ const char *s2, int result) {
+ if (!fuzzer::RunningUserCallback) return;
+ if (result == 0) return; // No reason to mutate.
+ size_t N = fuzzer::InternalStrnlen2(s1, s2);
+ if (N <= 1) return; // Not interesting.
+ fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, N, /*StopAtZero*/true);
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_strncasecmp(void *called_pc, const char *s1,
+ const char *s2, size_t n, int result) {
+ if (!fuzzer::RunningUserCallback) return;
+ return __sanitizer_weak_hook_strncmp(called_pc, s1, s2, n, result);
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_strcasecmp(void *called_pc, const char *s1,
+ const char *s2, int result) {
+ if (!fuzzer::RunningUserCallback) return;
+ return __sanitizer_weak_hook_strcmp(called_pc, s1, s2, result);
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1,
+ const char *s2, char *result) {
+ if (!fuzzer::RunningUserCallback) return;
+ fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1,
+ const char *s2, char *result) {
+ if (!fuzzer::RunningUserCallback) return;
+ fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
+}
+
+ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
+void __sanitizer_weak_hook_memmem(void *called_pc, const void *s1, size_t len1,
+ const void *s2, size_t len2, void *result) {
+ if (!fuzzer::RunningUserCallback) return;
+ fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), len2);
+}
+} // extern "C"
diff --git a/tools/fuzzing/libfuzzer/FuzzerTracePC.h b/tools/fuzzing/libfuzzer/FuzzerTracePC.h
new file mode 100644
index 0000000000..b46ebb909d
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerTracePC.h
@@ -0,0 +1,289 @@
+//===- FuzzerTracePC.h - Internal header for the Fuzzer ---------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// fuzzer::TracePC
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_TRACE_PC
+#define LLVM_FUZZER_TRACE_PC
+
+#include "FuzzerDefs.h"
+#include "FuzzerDictionary.h"
+#include "FuzzerValueBitMap.h"
+
+#include <set>
+#include <unordered_map>
+
+namespace fuzzer {
+
+// TableOfRecentCompares (TORC) remembers the most recently performed
+// comparisons of type T.
+// We record the arguments of CMP instructions in this table unconditionally
+// because it seems cheaper this way than to compute some expensive
+// conditions inside __sanitizer_cov_trace_cmp*.
+// After the unit has been executed we may decide to use the contents of
+// this table to populate a Dictionary.
+template<class T, size_t kSizeT>
+struct TableOfRecentCompares {
+ static const size_t kSize = kSizeT;
+ struct Pair {
+ T A, B;
+ };
+ ATTRIBUTE_NO_SANITIZE_ALL
+ void Insert(size_t Idx, const T &Arg1, const T &Arg2) {
+ Idx = Idx % kSize;
+ Table[Idx].A = Arg1;
+ Table[Idx].B = Arg2;
+ }
+
+ Pair Get(size_t I) { return Table[I % kSize]; }
+
+ Pair Table[kSize];
+};
+
+template <size_t kSizeT>
+struct MemMemTable {
+ static const size_t kSize = kSizeT;
+ Word MemMemWords[kSize];
+ Word EmptyWord;
+
+ void Add(const uint8_t *Data, size_t Size) {
+ if (Size <= 2) return;
+ Size = std::min(Size, Word::GetMaxSize());
+ size_t Idx = SimpleFastHash(Data, Size) % kSize;
+ MemMemWords[Idx].Set(Data, Size);
+ }
+ const Word &Get(size_t Idx) {
+ for (size_t i = 0; i < kSize; i++) {
+ const Word &W = MemMemWords[(Idx + i) % kSize];
+ if (W.size()) return W;
+ }
+ EmptyWord.Set(nullptr, 0);
+ return EmptyWord;
+ }
+};
+
+class TracePC {
+ public:
+ void HandleInline8bitCountersInit(uint8_t *Start, uint8_t *Stop);
+ void HandlePCsInit(const uintptr_t *Start, const uintptr_t *Stop);
+ void HandleCallerCallee(uintptr_t Caller, uintptr_t Callee);
+ template <class T> void HandleCmp(uintptr_t PC, T Arg1, T Arg2);
+ size_t GetTotalPCCoverage();
+ void SetUseCounters(bool UC) { UseCounters = UC; }
+ void SetUseValueProfileMask(uint32_t VPMask) { UseValueProfileMask = VPMask; }
+ void SetPrintNewPCs(bool P) { DoPrintNewPCs = P; }
+ void SetPrintNewFuncs(size_t P) { NumPrintNewFuncs = P; }
+ void UpdateObservedPCs();
+ template <class Callback> void CollectFeatures(Callback CB) const;
+
+ void ResetMaps() {
+ ValueProfileMap.Reset();
+ ClearExtraCounters();
+ ClearInlineCounters();
+ }
+
+ void ClearInlineCounters();
+
+ void UpdateFeatureSet(size_t CurrentElementIdx, size_t CurrentElementSize);
+ void PrintFeatureSet();
+
+ void PrintModuleInfo();
+
+ void PrintCoverage();
+
+ template<class CallBack>
+ void IterateCoveredFunctions(CallBack CB);
+
+ void AddValueForMemcmp(void *caller_pc, const void *s1, const void *s2,
+ size_t n, bool StopAtZero);
+
+ TableOfRecentCompares<uint32_t, 32> TORC4;
+ TableOfRecentCompares<uint64_t, 32> TORC8;
+ TableOfRecentCompares<Word, 32> TORCW;
+ MemMemTable<1024> MMT;
+
+ void RecordInitialStack();
+ uintptr_t GetMaxStackOffset() const;
+
+ template<class CallBack>
+ void ForEachObservedPC(CallBack CB) {
+ for (auto PC : ObservedPCs)
+ CB(PC);
+ }
+
+ int SetFocusFunction(const std::string &FuncName);
+ bool ObservedFocusFunction();
+
+ struct PCTableEntry {
+ uintptr_t PC, PCFlags;
+ };
+
+ uintptr_t PCTableEntryIdx(const PCTableEntry *TE);
+ const PCTableEntry *PCTableEntryByIdx(uintptr_t Idx);
+ static uintptr_t GetNextInstructionPc(uintptr_t PC);
+ bool PcIsFuncEntry(const PCTableEntry *TE) { return TE->PCFlags & 1; }
+
+private:
+ bool UseCounters = false;
+ uint32_t UseValueProfileMask = false;
+ bool DoPrintNewPCs = false;
+ size_t NumPrintNewFuncs = 0;
+
+ // Module represents the array of 8-bit counters split into regions
+ // such that every region, except maybe the first and the last one, is one
+ // full page.
+ struct Module {
+ struct Region {
+ uint8_t *Start, *Stop;
+ bool Enabled;
+ bool OneFullPage;
+ };
+ Region *Regions;
+ size_t NumRegions;
+ uint8_t *Start() { return Regions[0].Start; }
+ uint8_t *Stop() { return Regions[NumRegions - 1].Stop; }
+ size_t Size() { return Stop() - Start(); }
+ size_t Idx(uint8_t *P) {
+ assert(P >= Start() && P < Stop());
+ return P - Start();
+ }
+ };
+
+ Module Modules[4096];
+ size_t NumModules; // linker-initialized.
+ size_t NumInline8bitCounters;
+
+ template <class Callback>
+ void IterateCounterRegions(Callback CB) {
+ for (size_t m = 0; m < NumModules; m++)
+ for (size_t r = 0; r < Modules[m].NumRegions; r++)
+ CB(Modules[m].Regions[r]);
+ }
+
+ struct { const PCTableEntry *Start, *Stop; } ModulePCTable[4096];
+ size_t NumPCTables;
+ size_t NumPCsInPCTables;
+
+ Set<const PCTableEntry*> ObservedPCs;
+ std::unordered_map<uintptr_t, uintptr_t> ObservedFuncs; // PC => Counter.
+
+ uint8_t *FocusFunctionCounterPtr = nullptr;
+
+ ValueBitMap ValueProfileMap;
+ uintptr_t InitialStack;
+};
+
+template <class Callback>
+// void Callback(size_t FirstFeature, size_t Idx, uint8_t Value);
+ATTRIBUTE_NO_SANITIZE_ALL
+size_t ForEachNonZeroByte(const uint8_t *Begin, const uint8_t *End,
+ size_t FirstFeature, Callback Handle8bitCounter) {
+ typedef uintptr_t LargeType;
+ const size_t Step = sizeof(LargeType) / sizeof(uint8_t);
+ const size_t StepMask = Step - 1;
+ auto P = Begin;
+ // Iterate by 1 byte until either the alignment boundary or the end.
+ for (; reinterpret_cast<uintptr_t>(P) & StepMask && P < End; P++)
+ if (uint8_t V = *P)
+ Handle8bitCounter(FirstFeature, P - Begin, V);
+
+ // Iterate by Step bytes at a time.
+ for (; P < End; P += Step)
+ if (LargeType Bundle = *reinterpret_cast<const LargeType *>(P))
+ for (size_t I = 0; I < Step; I++, Bundle >>= 8)
+ if (uint8_t V = Bundle & 0xff)
+ Handle8bitCounter(FirstFeature, P - Begin + I, V);
+
+ // Iterate by 1 byte until the end.
+ for (; P < End; P++)
+ if (uint8_t V = *P)
+ Handle8bitCounter(FirstFeature, P - Begin, V);
+ return End - Begin;
+}
+
+// Given a non-zero Counter returns a number in the range [0,7].
+template<class T>
+unsigned CounterToFeature(T Counter) {
+ // Returns a feature number by placing Counters into buckets as illustrated
+ // below.
+ //
+ // Counter bucket: [1] [2] [3] [4-7] [8-15] [16-31] [32-127] [128+]
+ // Feature number: 0 1 2 3 4 5 6 7
+ //
+ // This is a heuristic taken from AFL (see
+ // http://lcamtuf.coredump.cx/afl/technical_details.txt).
+ //
+ // This implementation may change in the future so clients should
+ // not rely on it.
+ assert(Counter);
+ unsigned Bit = 0;
+ /**/ if (Counter >= 128) Bit = 7;
+ else if (Counter >= 32) Bit = 6;
+ else if (Counter >= 16) Bit = 5;
+ else if (Counter >= 8) Bit = 4;
+ else if (Counter >= 4) Bit = 3;
+ else if (Counter >= 3) Bit = 2;
+ else if (Counter >= 2) Bit = 1;
+ return Bit;
+}
+
+template <class Callback> // void Callback(size_t Feature)
+ATTRIBUTE_NO_SANITIZE_ADDRESS
+ATTRIBUTE_NOINLINE
+void TracePC::CollectFeatures(Callback HandleFeature) const {
+ auto Handle8bitCounter = [&](size_t FirstFeature,
+ size_t Idx, uint8_t Counter) {
+ if (UseCounters)
+ HandleFeature(FirstFeature + Idx * 8 + CounterToFeature(Counter));
+ else
+ HandleFeature(FirstFeature + Idx);
+ };
+
+ size_t FirstFeature = 0;
+
+ for (size_t i = 0; i < NumModules; i++) {
+ for (size_t r = 0; r < Modules[i].NumRegions; r++) {
+ if (!Modules[i].Regions[r].Enabled) continue;
+ FirstFeature += 8 * ForEachNonZeroByte(Modules[i].Regions[r].Start,
+ Modules[i].Regions[r].Stop,
+ FirstFeature, Handle8bitCounter);
+ }
+ }
+
+ FirstFeature +=
+ 8 * ForEachNonZeroByte(ExtraCountersBegin(), ExtraCountersEnd(),
+ FirstFeature, Handle8bitCounter);
+
+ if (UseValueProfileMask) {
+ ValueProfileMap.ForEach([&](size_t Idx) {
+ HandleFeature(FirstFeature + Idx);
+ });
+ FirstFeature += ValueProfileMap.SizeInBits();
+ }
+
+ // Step function, grows similar to 8 * Log_2(A).
+ auto StackDepthStepFunction = [](uint32_t A) -> uint32_t {
+ if (!A) return A;
+ uint32_t Log2 = Log(A);
+ if (Log2 < 3) return A;
+ Log2 -= 3;
+ return (Log2 + 1) * 8 + ((A >> Log2) & 7);
+ };
+ assert(StackDepthStepFunction(1024) == 64);
+ assert(StackDepthStepFunction(1024 * 4) == 80);
+ assert(StackDepthStepFunction(1024 * 1024) == 144);
+
+ if (auto MaxStackOffset = GetMaxStackOffset())
+ HandleFeature(FirstFeature + StackDepthStepFunction(MaxStackOffset / 8));
+}
+
+extern TracePC TPC;
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_TRACE_PC
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtil.cpp b/tools/fuzzing/libfuzzer/FuzzerUtil.cpp
new file mode 100644
index 0000000000..7eecb68d07
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtil.cpp
@@ -0,0 +1,236 @@
+//===- FuzzerUtil.cpp - Misc utils ----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Misc utils.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerUtil.h"
+#include "FuzzerIO.h"
+#include "FuzzerInternal.h"
+#include <cassert>
+#include <chrono>
+#include <cstring>
+#include <errno.h>
+#include <mutex>
+#include <signal.h>
+#include <sstream>
+#include <stdio.h>
+#include <sys/types.h>
+#include <thread>
+
+namespace fuzzer {
+
+void PrintHexArray(const uint8_t *Data, size_t Size,
+ const char *PrintAfter) {
+ for (size_t i = 0; i < Size; i++)
+ Printf("0x%x,", (unsigned)Data[i]);
+ Printf("%s", PrintAfter);
+}
+
+void Print(const Unit &v, const char *PrintAfter) {
+ PrintHexArray(v.data(), v.size(), PrintAfter);
+}
+
+void PrintASCIIByte(uint8_t Byte) {
+ if (Byte == '\\')
+ Printf("\\\\");
+ else if (Byte == '"')
+ Printf("\\\"");
+ else if (Byte >= 32 && Byte < 127)
+ Printf("%c", Byte);
+ else
+ Printf("\\x%02x", Byte);
+}
+
+void PrintASCII(const uint8_t *Data, size_t Size, const char *PrintAfter) {
+ for (size_t i = 0; i < Size; i++)
+ PrintASCIIByte(Data[i]);
+ Printf("%s", PrintAfter);
+}
+
+void PrintASCII(const Unit &U, const char *PrintAfter) {
+ PrintASCII(U.data(), U.size(), PrintAfter);
+}
+
+bool ToASCII(uint8_t *Data, size_t Size) {
+ bool Changed = false;
+ for (size_t i = 0; i < Size; i++) {
+ uint8_t &X = Data[i];
+ auto NewX = X;
+ NewX &= 127;
+ if (!isspace(NewX) && !isprint(NewX))
+ NewX = ' ';
+ Changed |= NewX != X;
+ X = NewX;
+ }
+ return Changed;
+}
+
+bool IsASCII(const Unit &U) { return IsASCII(U.data(), U.size()); }
+
+bool IsASCII(const uint8_t *Data, size_t Size) {
+ for (size_t i = 0; i < Size; i++)
+ if (!(isprint(Data[i]) || isspace(Data[i]))) return false;
+ return true;
+}
+
+bool ParseOneDictionaryEntry(const std::string &Str, Unit *U) {
+ U->clear();
+ if (Str.empty()) return false;
+ size_t L = 0, R = Str.size() - 1; // We are parsing the range [L,R].
+ // Skip spaces from both sides.
+ while (L < R && isspace(Str[L])) L++;
+ while (R > L && isspace(Str[R])) R--;
+ if (R - L < 2) return false;
+ // Check the closing "
+ if (Str[R] != '"') return false;
+ R--;
+ // Find the opening "
+ while (L < R && Str[L] != '"') L++;
+ if (L >= R) return false;
+ assert(Str[L] == '\"');
+ L++;
+ assert(L <= R);
+ for (size_t Pos = L; Pos <= R; Pos++) {
+ uint8_t V = (uint8_t)Str[Pos];
+ if (!isprint(V) && !isspace(V)) return false;
+ if (V =='\\') {
+ // Handle '\\'
+ if (Pos + 1 <= R && (Str[Pos + 1] == '\\' || Str[Pos + 1] == '"')) {
+ U->push_back(Str[Pos + 1]);
+ Pos++;
+ continue;
+ }
+ // Handle '\xAB'
+ if (Pos + 3 <= R && Str[Pos + 1] == 'x'
+ && isxdigit(Str[Pos + 2]) && isxdigit(Str[Pos + 3])) {
+ char Hex[] = "0xAA";
+ Hex[2] = Str[Pos + 2];
+ Hex[3] = Str[Pos + 3];
+ U->push_back(strtol(Hex, nullptr, 16));
+ Pos += 3;
+ continue;
+ }
+ return false; // Invalid escape.
+ } else {
+ // Any other character.
+ U->push_back(V);
+ }
+ }
+ return true;
+}
+
+bool ParseDictionaryFile(const std::string &Text, Vector<Unit> *Units) {
+ if (Text.empty()) {
+ Printf("ParseDictionaryFile: file does not exist or is empty\n");
+ return false;
+ }
+ std::istringstream ISS(Text);
+ Units->clear();
+ Unit U;
+ int LineNo = 0;
+ std::string S;
+ while (std::getline(ISS, S, '\n')) {
+ LineNo++;
+ size_t Pos = 0;
+ while (Pos < S.size() && isspace(S[Pos])) Pos++; // Skip spaces.
+ if (Pos == S.size()) continue; // Empty line.
+ if (S[Pos] == '#') continue; // Comment line.
+ if (ParseOneDictionaryEntry(S, &U)) {
+ Units->push_back(U);
+ } else {
+ Printf("ParseDictionaryFile: error in line %d\n\t\t%s\n", LineNo,
+ S.c_str());
+ return false;
+ }
+ }
+ return true;
+}
+
+// Code duplicated (and tested) in llvm/include/llvm/Support/Base64.h
+std::string Base64(const Unit &U) {
+ static const char Table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/";
+ std::string Buffer;
+ Buffer.resize(((U.size() + 2) / 3) * 4);
+
+ size_t i = 0, j = 0;
+ for (size_t n = U.size() / 3 * 3; i < n; i += 3, j += 4) {
+ uint32_t x = ((unsigned char)U[i] << 16) | ((unsigned char)U[i + 1] << 8) |
+ (unsigned char)U[i + 2];
+ Buffer[j + 0] = Table[(x >> 18) & 63];
+ Buffer[j + 1] = Table[(x >> 12) & 63];
+ Buffer[j + 2] = Table[(x >> 6) & 63];
+ Buffer[j + 3] = Table[x & 63];
+ }
+ if (i + 1 == U.size()) {
+ uint32_t x = ((unsigned char)U[i] << 16);
+ Buffer[j + 0] = Table[(x >> 18) & 63];
+ Buffer[j + 1] = Table[(x >> 12) & 63];
+ Buffer[j + 2] = '=';
+ Buffer[j + 3] = '=';
+ } else if (i + 2 == U.size()) {
+ uint32_t x = ((unsigned char)U[i] << 16) | ((unsigned char)U[i + 1] << 8);
+ Buffer[j + 0] = Table[(x >> 18) & 63];
+ Buffer[j + 1] = Table[(x >> 12) & 63];
+ Buffer[j + 2] = Table[(x >> 6) & 63];
+ Buffer[j + 3] = '=';
+ }
+ return Buffer;
+}
+
+static std::mutex SymbolizeMutex;
+
+std::string DescribePC(const char *SymbolizedFMT, uintptr_t PC) {
+ std::unique_lock<std::mutex> l(SymbolizeMutex, std::try_to_lock);
+ if (!EF->__sanitizer_symbolize_pc || !l.owns_lock())
+ return "<can not symbolize>";
+ char PcDescr[1024] = {};
+ EF->__sanitizer_symbolize_pc(reinterpret_cast<void*>(PC),
+ SymbolizedFMT, PcDescr, sizeof(PcDescr));
+ PcDescr[sizeof(PcDescr) - 1] = 0; // Just in case.
+ return PcDescr;
+}
+
+void PrintPC(const char *SymbolizedFMT, const char *FallbackFMT, uintptr_t PC) {
+ if (EF->__sanitizer_symbolize_pc)
+ Printf("%s", DescribePC(SymbolizedFMT, PC).c_str());
+ else
+ Printf(FallbackFMT, PC);
+}
+
+void PrintStackTrace() {
+ std::unique_lock<std::mutex> l(SymbolizeMutex, std::try_to_lock);
+ if (EF->__sanitizer_print_stack_trace && l.owns_lock())
+ EF->__sanitizer_print_stack_trace();
+}
+
+void PrintMemoryProfile() {
+ std::unique_lock<std::mutex> l(SymbolizeMutex, std::try_to_lock);
+ if (EF->__sanitizer_print_memory_profile && l.owns_lock())
+ EF->__sanitizer_print_memory_profile(95, 8);
+}
+
+unsigned NumberOfCpuCores() {
+ unsigned N = std::thread::hardware_concurrency();
+ if (!N) {
+ Printf("WARNING: std::thread::hardware_concurrency not well defined for "
+ "your platform. Assuming CPU count of 1.\n");
+ N = 1;
+ }
+ return N;
+}
+
+size_t SimpleFastHash(const uint8_t *Data, size_t Size) {
+ size_t Res = 0;
+ for (size_t i = 0; i < Size; i++)
+ Res = Res * 11 + Data[i];
+ return Res;
+}
+
+} // namespace fuzzer
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtil.h b/tools/fuzzing/libfuzzer/FuzzerUtil.h
new file mode 100644
index 0000000000..4ae3583830
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtil.h
@@ -0,0 +1,111 @@
+//===- FuzzerUtil.h - Internal header for the Fuzzer Utils ------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Util functions.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_UTIL_H
+#define LLVM_FUZZER_UTIL_H
+
+#include "FuzzerBuiltins.h"
+#include "FuzzerBuiltinsMsvc.h"
+#include "FuzzerCommand.h"
+#include "FuzzerDefs.h"
+
+namespace fuzzer {
+
+void PrintHexArray(const Unit &U, const char *PrintAfter = "");
+
+void PrintHexArray(const uint8_t *Data, size_t Size,
+ const char *PrintAfter = "");
+
+void PrintASCII(const uint8_t *Data, size_t Size, const char *PrintAfter = "");
+
+void PrintASCII(const Unit &U, const char *PrintAfter = "");
+
+// Changes U to contain only ASCII (isprint+isspace) characters.
+// Returns true iff U has been changed.
+bool ToASCII(uint8_t *Data, size_t Size);
+
+bool IsASCII(const Unit &U);
+
+bool IsASCII(const uint8_t *Data, size_t Size);
+
+std::string Base64(const Unit &U);
+
+void PrintPC(const char *SymbolizedFMT, const char *FallbackFMT, uintptr_t PC);
+
+std::string DescribePC(const char *SymbolizedFMT, uintptr_t PC);
+
+void PrintStackTrace();
+
+void PrintMemoryProfile();
+
+unsigned NumberOfCpuCores();
+
+// Platform specific functions.
+void SetSignalHandler(const FuzzingOptions& Options);
+
+void SleepSeconds(int Seconds);
+
+unsigned long GetPid();
+
+size_t GetPeakRSSMb();
+
+int ExecuteCommand(const Command &Cmd);
+bool ExecuteCommand(const Command &Cmd, std::string *CmdOutput);
+
+// Fuchsia does not have popen/pclose.
+FILE *OpenProcessPipe(const char *Command, const char *Mode);
+int CloseProcessPipe(FILE *F);
+
+const void *SearchMemory(const void *haystack, size_t haystacklen,
+ const void *needle, size_t needlelen);
+
+std::string CloneArgsWithoutX(const Vector<std::string> &Args,
+ const char *X1, const char *X2);
+
+inline std::string CloneArgsWithoutX(const Vector<std::string> &Args,
+ const char *X) {
+ return CloneArgsWithoutX(Args, X, X);
+}
+
+inline std::pair<std::string, std::string> SplitBefore(std::string X,
+ std::string S) {
+ auto Pos = S.find(X);
+ if (Pos == std::string::npos)
+ return std::make_pair(S, "");
+ return std::make_pair(S.substr(0, Pos), S.substr(Pos));
+}
+
+void DiscardOutput(int Fd);
+
+std::string DisassembleCmd(const std::string &FileName);
+
+std::string SearchRegexCmd(const std::string &Regex);
+
+size_t SimpleFastHash(const uint8_t *Data, size_t Size);
+
+inline uint32_t Log(uint32_t X) { return 32 - Clz(X) - 1; }
+
+inline size_t PageSize() { return 4096; }
+inline uint8_t *RoundUpByPage(uint8_t *P) {
+ uintptr_t X = reinterpret_cast<uintptr_t>(P);
+ size_t Mask = PageSize() - 1;
+ X = (X + Mask) & ~Mask;
+ return reinterpret_cast<uint8_t *>(X);
+}
+inline uint8_t *RoundDownByPage(uint8_t *P) {
+ uintptr_t X = reinterpret_cast<uintptr_t>(P);
+ size_t Mask = PageSize() - 1;
+ X = X & ~Mask;
+ return reinterpret_cast<uint8_t *>(X);
+}
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_UTIL_H
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtilDarwin.cpp b/tools/fuzzing/libfuzzer/FuzzerUtilDarwin.cpp
new file mode 100644
index 0000000000..a5bed658a4
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtilDarwin.cpp
@@ -0,0 +1,170 @@
+//===- FuzzerUtilDarwin.cpp - Misc utils ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Misc utils for Darwin.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_APPLE
+#include "FuzzerCommand.h"
+#include "FuzzerIO.h"
+#include <mutex>
+#include <signal.h>
+#include <spawn.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+// There is no header for this on macOS so declare here
+extern "C" char **environ;
+
+namespace fuzzer {
+
+static std::mutex SignalMutex;
+// Global variables used to keep track of how signal handling should be
+// restored. They should **not** be accessed without holding `SignalMutex`.
+static int ActiveThreadCount = 0;
+static struct sigaction OldSigIntAction;
+static struct sigaction OldSigQuitAction;
+static sigset_t OldBlockedSignalsSet;
+
+// This is a reimplementation of Libc's `system()`. On Darwin the Libc
+// implementation contains a mutex which prevents it from being used
+// concurrently. This implementation **can** be used concurrently. It sets the
+// signal handlers when the first thread enters and restores them when the last
+// thread finishes execution of the function and ensures this is not racey by
+// using a mutex.
+int ExecuteCommand(const Command &Cmd) {
+ std::string CmdLine = Cmd.toString();
+ posix_spawnattr_t SpawnAttributes;
+ if (posix_spawnattr_init(&SpawnAttributes))
+ return -1;
+ // Block and ignore signals of the current process when the first thread
+ // enters.
+ {
+ std::lock_guard<std::mutex> Lock(SignalMutex);
+ if (ActiveThreadCount == 0) {
+ static struct sigaction IgnoreSignalAction;
+ sigset_t BlockedSignalsSet;
+ memset(&IgnoreSignalAction, 0, sizeof(IgnoreSignalAction));
+ IgnoreSignalAction.sa_handler = SIG_IGN;
+
+ if (sigaction(SIGINT, &IgnoreSignalAction, &OldSigIntAction) == -1) {
+ Printf("Failed to ignore SIGINT\n");
+ (void)posix_spawnattr_destroy(&SpawnAttributes);
+ return -1;
+ }
+ if (sigaction(SIGQUIT, &IgnoreSignalAction, &OldSigQuitAction) == -1) {
+ Printf("Failed to ignore SIGQUIT\n");
+ // Try our best to restore the signal handlers.
+ (void)sigaction(SIGINT, &OldSigIntAction, NULL);
+ (void)posix_spawnattr_destroy(&SpawnAttributes);
+ return -1;
+ }
+
+ (void)sigemptyset(&BlockedSignalsSet);
+ (void)sigaddset(&BlockedSignalsSet, SIGCHLD);
+ if (sigprocmask(SIG_BLOCK, &BlockedSignalsSet, &OldBlockedSignalsSet) ==
+ -1) {
+ Printf("Failed to block SIGCHLD\n");
+ // Try our best to restore the signal handlers.
+ (void)sigaction(SIGQUIT, &OldSigQuitAction, NULL);
+ (void)sigaction(SIGINT, &OldSigIntAction, NULL);
+ (void)posix_spawnattr_destroy(&SpawnAttributes);
+ return -1;
+ }
+ }
+ ++ActiveThreadCount;
+ }
+
+ // NOTE: Do not introduce any new `return` statements past this
+ // point. It is important that `ActiveThreadCount` always be decremented
+ // when leaving this function.
+
+ // Make sure the child process uses the default handlers for the
+ // following signals rather than inheriting what the parent has.
+ sigset_t DefaultSigSet;
+ (void)sigemptyset(&DefaultSigSet);
+ (void)sigaddset(&DefaultSigSet, SIGQUIT);
+ (void)sigaddset(&DefaultSigSet, SIGINT);
+ (void)posix_spawnattr_setsigdefault(&SpawnAttributes, &DefaultSigSet);
+ // Make sure the child process doesn't block SIGCHLD
+ (void)posix_spawnattr_setsigmask(&SpawnAttributes, &OldBlockedSignalsSet);
+ short SpawnFlags = POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK;
+ (void)posix_spawnattr_setflags(&SpawnAttributes, SpawnFlags);
+
+ pid_t Pid;
+ char **Environ = environ; // Read from global
+ const char *CommandCStr = CmdLine.c_str();
+ char *const Argv[] = {
+ strdup("sh"),
+ strdup("-c"),
+ strdup(CommandCStr),
+ NULL
+ };
+ int ErrorCode = 0, ProcessStatus = 0;
+ // FIXME: We probably shouldn't hardcode the shell path.
+ ErrorCode = posix_spawn(&Pid, "/bin/sh", NULL, &SpawnAttributes,
+ Argv, Environ);
+ (void)posix_spawnattr_destroy(&SpawnAttributes);
+ if (!ErrorCode) {
+ pid_t SavedPid = Pid;
+ do {
+ // Repeat until call completes uninterrupted.
+ Pid = waitpid(SavedPid, &ProcessStatus, /*options=*/0);
+ } while (Pid == -1 && errno == EINTR);
+ if (Pid == -1) {
+ // Fail for some other reason.
+ ProcessStatus = -1;
+ }
+ } else if (ErrorCode == ENOMEM || ErrorCode == EAGAIN) {
+ // Fork failure.
+ ProcessStatus = -1;
+ } else {
+ // Shell execution failure.
+ ProcessStatus = W_EXITCODE(127, 0);
+ }
+ for (unsigned i = 0, n = sizeof(Argv) / sizeof(Argv[0]); i < n; ++i)
+ free(Argv[i]);
+
+ // Restore the signal handlers of the current process when the last thread
+ // using this function finishes.
+ {
+ std::lock_guard<std::mutex> Lock(SignalMutex);
+ --ActiveThreadCount;
+ if (ActiveThreadCount == 0) {
+ bool FailedRestore = false;
+ if (sigaction(SIGINT, &OldSigIntAction, NULL) == -1) {
+ Printf("Failed to restore SIGINT handling\n");
+ FailedRestore = true;
+ }
+ if (sigaction(SIGQUIT, &OldSigQuitAction, NULL) == -1) {
+ Printf("Failed to restore SIGQUIT handling\n");
+ FailedRestore = true;
+ }
+ if (sigprocmask(SIG_BLOCK, &OldBlockedSignalsSet, NULL) == -1) {
+ Printf("Failed to unblock SIGCHLD\n");
+ FailedRestore = true;
+ }
+ if (FailedRestore)
+ ProcessStatus = -1;
+ }
+ }
+ return ProcessStatus;
+}
+
+void DiscardOutput(int Fd) {
+ FILE* Temp = fopen("/dev/null", "w");
+ if (!Temp)
+ return;
+ dup2(fileno(Temp), Fd);
+ fclose(Temp);
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_APPLE
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtilFuchsia.cpp b/tools/fuzzing/libfuzzer/FuzzerUtilFuchsia.cpp
new file mode 100644
index 0000000000..190fb78666
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtilFuchsia.cpp
@@ -0,0 +1,565 @@
+//===- FuzzerUtilFuchsia.cpp - Misc utils for Fuchsia. --------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Misc utils implementation using Fuchsia/Zircon APIs.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+
+#if LIBFUZZER_FUCHSIA
+
+#include "FuzzerInternal.h"
+#include "FuzzerUtil.h"
+#include <cassert>
+#include <cerrno>
+#include <cinttypes>
+#include <cstdint>
+#include <fcntl.h>
+#include <lib/fdio/fdio.h>
+#include <lib/fdio/spawn.h>
+#include <string>
+#include <sys/select.h>
+#include <thread>
+#include <unistd.h>
+#include <zircon/errors.h>
+#include <zircon/process.h>
+#include <zircon/sanitizer.h>
+#include <zircon/status.h>
+#include <zircon/syscalls.h>
+#include <zircon/syscalls/debug.h>
+#include <zircon/syscalls/exception.h>
+#include <zircon/syscalls/object.h>
+#include <zircon/types.h>
+
+#include <vector>
+
+namespace fuzzer {
+
+// Given that Fuchsia doesn't have the POSIX signals that libFuzzer was written
+// around, the general approach is to spin up dedicated threads to watch for
+// each requested condition (alarm, interrupt, crash). Of these, the crash
+// handler is the most involved, as it requires resuming the crashed thread in
+// order to invoke the sanitizers to get the needed state.
+
+// Forward declaration of assembly trampoline needed to resume crashed threads.
+// This appears to have external linkage to C++, which is why it's not in the
+// anonymous namespace. The assembly definition inside MakeTrampoline()
+// actually defines the symbol with internal linkage only.
+void CrashTrampolineAsm() __asm__("CrashTrampolineAsm");
+
+namespace {
+
+// Helper function to handle Zircon syscall failures.
+void ExitOnErr(zx_status_t Status, const char *Syscall) {
+ if (Status != ZX_OK) {
+ Printf("libFuzzer: %s failed: %s\n", Syscall,
+ _zx_status_get_string(Status));
+ exit(1);
+ }
+}
+
+void AlarmHandler(int Seconds) {
+ while (true) {
+ SleepSeconds(Seconds);
+ Fuzzer::StaticAlarmCallback();
+ }
+}
+
+void InterruptHandler() {
+ fd_set readfds;
+ // Ctrl-C sends ETX in Zircon.
+ do {
+ FD_ZERO(&readfds);
+ FD_SET(STDIN_FILENO, &readfds);
+ select(STDIN_FILENO + 1, &readfds, nullptr, nullptr, nullptr);
+ } while(!FD_ISSET(STDIN_FILENO, &readfds) || getchar() != 0x03);
+ Fuzzer::StaticInterruptCallback();
+}
+
+// CFAOffset is used to reference the stack pointer before entering the
+// trampoline (Stack Pointer + CFAOffset = prev Stack Pointer). Before jumping
+// to the trampoline we copy all the registers onto the stack. We need to make
+// sure that the new stack has enough space to store all the registers.
+//
+// The trampoline holds CFI information regarding the registers stored in the
+// stack, which is then used by the unwinder to restore them.
+#if defined(__x86_64__)
+// In x86_64 the crashing function might also be using the red zone (128 bytes
+// on top of their rsp).
+constexpr size_t CFAOffset = 128 + sizeof(zx_thread_state_general_regs_t);
+#elif defined(__aarch64__)
+// In aarch64 we need to always have the stack pointer aligned to 16 bytes, so we
+// make sure that we are keeping that same alignment.
+constexpr size_t CFAOffset = (sizeof(zx_thread_state_general_regs_t) + 15) & -(uintptr_t)16;
+#endif
+
+// For the crash handler, we need to call Fuzzer::StaticCrashSignalCallback
+// without POSIX signal handlers. To achieve this, we use an assembly function
+// to add the necessary CFI unwinding information and a C function to bridge
+// from that back into C++.
+
+// FIXME: This works as a short-term solution, but this code really shouldn't be
+// architecture dependent. A better long term solution is to implement remote
+// unwinding and expose the necessary APIs through sanitizer_common and/or ASAN
+// to allow the exception handling thread to gather the crash state directly.
+//
+// Alternatively, Fuchsia may in future actually implement basic signal
+// handling for the machine trap signals.
+#if defined(__x86_64__)
+#define FOREACH_REGISTER(OP_REG, OP_NUM) \
+ OP_REG(rax) \
+ OP_REG(rbx) \
+ OP_REG(rcx) \
+ OP_REG(rdx) \
+ OP_REG(rsi) \
+ OP_REG(rdi) \
+ OP_REG(rbp) \
+ OP_REG(rsp) \
+ OP_REG(r8) \
+ OP_REG(r9) \
+ OP_REG(r10) \
+ OP_REG(r11) \
+ OP_REG(r12) \
+ OP_REG(r13) \
+ OP_REG(r14) \
+ OP_REG(r15) \
+ OP_REG(rip)
+
+#elif defined(__aarch64__)
+#define FOREACH_REGISTER(OP_REG, OP_NUM) \
+ OP_NUM(0) \
+ OP_NUM(1) \
+ OP_NUM(2) \
+ OP_NUM(3) \
+ OP_NUM(4) \
+ OP_NUM(5) \
+ OP_NUM(6) \
+ OP_NUM(7) \
+ OP_NUM(8) \
+ OP_NUM(9) \
+ OP_NUM(10) \
+ OP_NUM(11) \
+ OP_NUM(12) \
+ OP_NUM(13) \
+ OP_NUM(14) \
+ OP_NUM(15) \
+ OP_NUM(16) \
+ OP_NUM(17) \
+ OP_NUM(18) \
+ OP_NUM(19) \
+ OP_NUM(20) \
+ OP_NUM(21) \
+ OP_NUM(22) \
+ OP_NUM(23) \
+ OP_NUM(24) \
+ OP_NUM(25) \
+ OP_NUM(26) \
+ OP_NUM(27) \
+ OP_NUM(28) \
+ OP_NUM(29) \
+ OP_REG(sp)
+
+#else
+#error "Unsupported architecture for fuzzing on Fuchsia"
+#endif
+
+// Produces a CFI directive for the named or numbered register.
+// The value used refers to an assembler immediate operand with the same name
+// as the register (see ASM_OPERAND_REG).
+#define CFI_OFFSET_REG(reg) ".cfi_offset " #reg ", %c[" #reg "]\n"
+#define CFI_OFFSET_NUM(num) CFI_OFFSET_REG(x##num)
+
+// Produces an assembler immediate operand for the named or numbered register.
+// This operand contains the offset of the register relative to the CFA.
+#define ASM_OPERAND_REG(reg) \
+ [reg] "i"(offsetof(zx_thread_state_general_regs_t, reg) - CFAOffset),
+#define ASM_OPERAND_NUM(num) \
+ [x##num] "i"(offsetof(zx_thread_state_general_regs_t, r[num]) - CFAOffset),
+
+// Trampoline to bridge from the assembly below to the static C++ crash
+// callback.
+__attribute__((noreturn))
+static void StaticCrashHandler() {
+ Fuzzer::StaticCrashSignalCallback();
+ for (;;) {
+ _Exit(1);
+ }
+}
+
+// Creates the trampoline with the necessary CFI information to unwind through
+// to the crashing call stack:
+// * Defining the CFA so that it points to the stack pointer at the point
+// of crash.
+// * Storing all registers at the point of crash in the stack and refer to them
+// via CFI information (relative to the CFA).
+// * Setting the return column so the unwinder knows how to continue unwinding.
+// * (x86_64) making sure rsp is aligned before calling StaticCrashHandler.
+// * Calling StaticCrashHandler that will trigger the unwinder.
+//
+// The __attribute__((used)) is necessary because the function
+// is never called; it's just a container around the assembly to allow it to
+// use operands for compile-time computed constants.
+__attribute__((used))
+void MakeTrampoline() {
+ __asm__(".cfi_endproc\n"
+ ".pushsection .text.CrashTrampolineAsm\n"
+ ".type CrashTrampolineAsm,STT_FUNC\n"
+"CrashTrampolineAsm:\n"
+ ".cfi_startproc simple\n"
+ ".cfi_signal_frame\n"
+#if defined(__x86_64__)
+ ".cfi_return_column rip\n"
+ ".cfi_def_cfa rsp, %c[CFAOffset]\n"
+ FOREACH_REGISTER(CFI_OFFSET_REG, CFI_OFFSET_NUM)
+ "mov %%rsp, %%rbp\n"
+ ".cfi_def_cfa_register rbp\n"
+ "andq $-16, %%rsp\n"
+ "call %c[StaticCrashHandler]\n"
+ "ud2\n"
+#elif defined(__aarch64__)
+ ".cfi_return_column 33\n"
+ ".cfi_def_cfa sp, %c[CFAOffset]\n"
+ FOREACH_REGISTER(CFI_OFFSET_REG, CFI_OFFSET_NUM)
+ ".cfi_offset 33, %c[pc]\n"
+ ".cfi_offset 30, %c[lr]\n"
+ "bl %c[StaticCrashHandler]\n"
+ "brk 1\n"
+#else
+#error "Unsupported architecture for fuzzing on Fuchsia"
+#endif
+ ".cfi_endproc\n"
+ ".size CrashTrampolineAsm, . - CrashTrampolineAsm\n"
+ ".popsection\n"
+ ".cfi_startproc\n"
+ : // No outputs
+ : FOREACH_REGISTER(ASM_OPERAND_REG, ASM_OPERAND_NUM)
+#if defined(__aarch64__)
+ ASM_OPERAND_REG(pc)
+ ASM_OPERAND_REG(lr)
+#endif
+ [StaticCrashHandler] "i" (StaticCrashHandler),
+ [CFAOffset] "i" (CFAOffset));
+}
+
+void CrashHandler(zx_handle_t *Event) {
+ // This structure is used to ensure we close handles to objects we create in
+ // this handler.
+ struct ScopedHandle {
+ ~ScopedHandle() { _zx_handle_close(Handle); }
+ zx_handle_t Handle = ZX_HANDLE_INVALID;
+ };
+
+ // Create the exception channel. We need to claim to be a "debugger" so the
+ // kernel will allow us to modify and resume dying threads (see below). Once
+ // the channel is set, we can signal the main thread to continue and wait
+ // for the exception to arrive.
+ ScopedHandle Channel;
+ zx_handle_t Self = _zx_process_self();
+ ExitOnErr(_zx_task_create_exception_channel(
+ Self, ZX_EXCEPTION_CHANNEL_DEBUGGER, &Channel.Handle),
+ "_zx_task_create_exception_channel");
+
+ ExitOnErr(_zx_object_signal(*Event, 0, ZX_USER_SIGNAL_0),
+ "_zx_object_signal");
+
+ // This thread lives as long as the process in order to keep handling
+ // crashes. In practice, the first crashed thread to reach the end of the
+ // StaticCrashHandler will end the process.
+ while (true) {
+ ExitOnErr(_zx_object_wait_one(Channel.Handle, ZX_CHANNEL_READABLE,
+ ZX_TIME_INFINITE, nullptr),
+ "_zx_object_wait_one");
+
+ zx_exception_info_t ExceptionInfo;
+ ScopedHandle Exception;
+ ExitOnErr(_zx_channel_read(Channel.Handle, 0, &ExceptionInfo,
+ &Exception.Handle, sizeof(ExceptionInfo), 1,
+ nullptr, nullptr),
+ "_zx_channel_read");
+
+ // Ignore informational synthetic exceptions.
+ if (ZX_EXCP_THREAD_STARTING == ExceptionInfo.type ||
+ ZX_EXCP_THREAD_EXITING == ExceptionInfo.type ||
+ ZX_EXCP_PROCESS_STARTING == ExceptionInfo.type) {
+ continue;
+ }
+
+ // At this point, we want to get the state of the crashing thread, but
+ // libFuzzer and the sanitizers assume this will happen from that same
+ // thread via a POSIX signal handler. "Resurrecting" the thread in the
+ // middle of the appropriate callback is as simple as forcibly setting the
+ // instruction pointer/program counter, provided we NEVER EVER return from
+ // that function (since otherwise our stack will not be valid).
+ ScopedHandle Thread;
+ ExitOnErr(_zx_exception_get_thread(Exception.Handle, &Thread.Handle),
+ "_zx_exception_get_thread");
+
+ zx_thread_state_general_regs_t GeneralRegisters;
+ ExitOnErr(_zx_thread_read_state(Thread.Handle, ZX_THREAD_STATE_GENERAL_REGS,
+ &GeneralRegisters,
+ sizeof(GeneralRegisters)),
+ "_zx_thread_read_state");
+
+ // To unwind properly, we need to push the crashing thread's register state
+ // onto the stack and jump into a trampoline with CFI instructions on how
+ // to restore it.
+#if defined(__x86_64__)
+ uintptr_t StackPtr = GeneralRegisters.rsp - CFAOffset;
+ __unsanitized_memcpy(reinterpret_cast<void *>(StackPtr), &GeneralRegisters,
+ sizeof(GeneralRegisters));
+ GeneralRegisters.rsp = StackPtr;
+ GeneralRegisters.rip = reinterpret_cast<zx_vaddr_t>(CrashTrampolineAsm);
+
+#elif defined(__aarch64__)
+ uintptr_t StackPtr = GeneralRegisters.sp - CFAOffset;
+ __unsanitized_memcpy(reinterpret_cast<void *>(StackPtr), &GeneralRegisters,
+ sizeof(GeneralRegisters));
+ GeneralRegisters.sp = StackPtr;
+ GeneralRegisters.pc = reinterpret_cast<zx_vaddr_t>(CrashTrampolineAsm);
+
+#else
+#error "Unsupported architecture for fuzzing on Fuchsia"
+#endif
+
+ // Now force the crashing thread's state.
+ ExitOnErr(
+ _zx_thread_write_state(Thread.Handle, ZX_THREAD_STATE_GENERAL_REGS,
+ &GeneralRegisters, sizeof(GeneralRegisters)),
+ "_zx_thread_write_state");
+
+ // Set the exception to HANDLED so it resumes the thread on close.
+ uint32_t ExceptionState = ZX_EXCEPTION_STATE_HANDLED;
+ ExitOnErr(_zx_object_set_property(Exception.Handle, ZX_PROP_EXCEPTION_STATE,
+ &ExceptionState, sizeof(ExceptionState)),
+ "zx_object_set_property");
+ }
+}
+
+} // namespace
+
+// Platform specific functions.
+void SetSignalHandler(const FuzzingOptions &Options) {
+ // Make sure information from libFuzzer and the sanitizers are easy to
+ // reassemble. `__sanitizer_log_write` has the added benefit of ensuring the
+ // DSO map is always available for the symbolizer.
+ // A uint64_t fits in 20 chars, so 64 is plenty.
+ char Buf[64];
+ memset(Buf, 0, sizeof(Buf));
+ snprintf(Buf, sizeof(Buf), "==%lu== INFO: libFuzzer starting.\n", GetPid());
+ if (EF->__sanitizer_log_write)
+ __sanitizer_log_write(Buf, sizeof(Buf));
+ Printf("%s", Buf);
+
+ // Set up alarm handler if needed.
+ if (Options.UnitTimeoutSec > 0) {
+ std::thread T(AlarmHandler, Options.UnitTimeoutSec / 2 + 1);
+ T.detach();
+ }
+
+ // Set up interrupt handler if needed.
+ if (Options.HandleInt || Options.HandleTerm) {
+ std::thread T(InterruptHandler);
+ T.detach();
+ }
+
+ // Early exit if no crash handler needed.
+ if (!Options.HandleSegv && !Options.HandleBus && !Options.HandleIll &&
+ !Options.HandleFpe && !Options.HandleAbrt)
+ return;
+
+ // Set up the crash handler and wait until it is ready before proceeding.
+ zx_handle_t Event;
+ ExitOnErr(_zx_event_create(0, &Event), "_zx_event_create");
+
+ std::thread T(CrashHandler, &Event);
+ zx_status_t Status =
+ _zx_object_wait_one(Event, ZX_USER_SIGNAL_0, ZX_TIME_INFINITE, nullptr);
+ _zx_handle_close(Event);
+ ExitOnErr(Status, "_zx_object_wait_one");
+
+ T.detach();
+}
+
+void SleepSeconds(int Seconds) {
+ _zx_nanosleep(_zx_deadline_after(ZX_SEC(Seconds)));
+}
+
+unsigned long GetPid() {
+ zx_status_t rc;
+ zx_info_handle_basic_t Info;
+ if ((rc = _zx_object_get_info(_zx_process_self(), ZX_INFO_HANDLE_BASIC, &Info,
+ sizeof(Info), NULL, NULL)) != ZX_OK) {
+ Printf("libFuzzer: unable to get info about self: %s\n",
+ _zx_status_get_string(rc));
+ exit(1);
+ }
+ return Info.koid;
+}
+
+size_t GetPeakRSSMb() {
+ zx_status_t rc;
+ zx_info_task_stats_t Info;
+ if ((rc = _zx_object_get_info(_zx_process_self(), ZX_INFO_TASK_STATS, &Info,
+ sizeof(Info), NULL, NULL)) != ZX_OK) {
+ Printf("libFuzzer: unable to get info about self: %s\n",
+ _zx_status_get_string(rc));
+ exit(1);
+ }
+ return (Info.mem_private_bytes + Info.mem_shared_bytes) >> 20;
+}
+
+template <typename Fn>
+class RunOnDestruction {
+ public:
+ explicit RunOnDestruction(Fn fn) : fn_(fn) {}
+ ~RunOnDestruction() { fn_(); }
+
+ private:
+ Fn fn_;
+};
+
+template <typename Fn>
+RunOnDestruction<Fn> at_scope_exit(Fn fn) {
+ return RunOnDestruction<Fn>(fn);
+}
+
+static fdio_spawn_action_t clone_fd_action(int localFd, int targetFd) {
+ return {
+ .action = FDIO_SPAWN_ACTION_CLONE_FD,
+ .fd =
+ {
+ .local_fd = localFd,
+ .target_fd = targetFd,
+ },
+ };
+}
+
+int ExecuteCommand(const Command &Cmd) {
+ zx_status_t rc;
+
+ // Convert arguments to C array
+ auto Args = Cmd.getArguments();
+ size_t Argc = Args.size();
+ assert(Argc != 0);
+ std::unique_ptr<const char *[]> Argv(new const char *[Argc + 1]);
+ for (size_t i = 0; i < Argc; ++i)
+ Argv[i] = Args[i].c_str();
+ Argv[Argc] = nullptr;
+
+ // Determine output. On Fuchsia, the fuzzer is typically run as a component
+ // that lacks a mutable working directory. Fortunately, when this is the case
+ // a mutable output directory must be specified using "-artifact_prefix=...",
+ // so write the log file(s) there.
+ // However, we don't want to apply this logic for absolute paths.
+ int FdOut = STDOUT_FILENO;
+ bool discardStdout = false;
+ bool discardStderr = false;
+
+ if (Cmd.hasOutputFile()) {
+ std::string Path = Cmd.getOutputFile();
+ if (Path == getDevNull()) {
+ // On Fuchsia, there's no "/dev/null" like-file, so we
+ // just don't copy the FDs into the spawned process.
+ discardStdout = true;
+ } else {
+ bool IsAbsolutePath = Path.length() > 1 && Path[0] == '/';
+ if (!IsAbsolutePath && Cmd.hasFlag("artifact_prefix"))
+ Path = Cmd.getFlagValue("artifact_prefix") + "/" + Path;
+
+ FdOut = open(Path.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0);
+ if (FdOut == -1) {
+ Printf("libFuzzer: failed to open %s: %s\n", Path.c_str(),
+ strerror(errno));
+ return ZX_ERR_IO;
+ }
+ }
+ }
+ auto CloseFdOut = at_scope_exit([FdOut]() {
+ if (FdOut != STDOUT_FILENO)
+ close(FdOut);
+ });
+
+ // Determine stderr
+ int FdErr = STDERR_FILENO;
+ if (Cmd.isOutAndErrCombined()) {
+ FdErr = FdOut;
+ if (discardStdout)
+ discardStderr = true;
+ }
+
+ // Clone the file descriptors into the new process
+ std::vector<fdio_spawn_action_t> SpawnActions;
+ SpawnActions.push_back(clone_fd_action(STDIN_FILENO, STDIN_FILENO));
+
+ if (!discardStdout)
+ SpawnActions.push_back(clone_fd_action(FdOut, STDOUT_FILENO));
+ if (!discardStderr)
+ SpawnActions.push_back(clone_fd_action(FdErr, STDERR_FILENO));
+
+ // Start the process.
+ char ErrorMsg[FDIO_SPAWN_ERR_MSG_MAX_LENGTH];
+ zx_handle_t ProcessHandle = ZX_HANDLE_INVALID;
+ rc = fdio_spawn_etc(ZX_HANDLE_INVALID,
+ FDIO_SPAWN_CLONE_ALL & (~FDIO_SPAWN_CLONE_STDIO), Argv[0],
+ Argv.get(), nullptr, SpawnActions.size(),
+ SpawnActions.data(), &ProcessHandle, ErrorMsg);
+
+ if (rc != ZX_OK) {
+ Printf("libFuzzer: failed to launch '%s': %s, %s\n", Argv[0], ErrorMsg,
+ _zx_status_get_string(rc));
+ return rc;
+ }
+ auto CloseHandle = at_scope_exit([&]() { _zx_handle_close(ProcessHandle); });
+
+ // Now join the process and return the exit status.
+ if ((rc = _zx_object_wait_one(ProcessHandle, ZX_PROCESS_TERMINATED,
+ ZX_TIME_INFINITE, nullptr)) != ZX_OK) {
+ Printf("libFuzzer: failed to join '%s': %s\n", Argv[0],
+ _zx_status_get_string(rc));
+ return rc;
+ }
+
+ zx_info_process_t Info;
+ if ((rc = _zx_object_get_info(ProcessHandle, ZX_INFO_PROCESS, &Info,
+ sizeof(Info), nullptr, nullptr)) != ZX_OK) {
+ Printf("libFuzzer: unable to get return code from '%s': %s\n", Argv[0],
+ _zx_status_get_string(rc));
+ return rc;
+ }
+
+ return Info.return_code;
+}
+
+bool ExecuteCommand(const Command &BaseCmd, std::string *CmdOutput) {
+ auto LogFilePath = TempPath("SimPopenOut", ".txt");
+ Command Cmd(BaseCmd);
+ Cmd.setOutputFile(LogFilePath);
+ int Ret = ExecuteCommand(Cmd);
+ *CmdOutput = FileToString(LogFilePath);
+ RemoveFile(LogFilePath);
+ return Ret == 0;
+}
+
+const void *SearchMemory(const void *Data, size_t DataLen, const void *Patt,
+ size_t PattLen) {
+ return memmem(Data, DataLen, Patt, PattLen);
+}
+
+// In fuchsia, accessing /dev/null is not supported. There's nothing
+// similar to a file that discards everything that is written to it.
+// The way of doing something similar in fuchsia is by using
+// fdio_null_create and binding that to a file descriptor.
+void DiscardOutput(int Fd) {
+ fdio_t *fdio_null = fdio_null_create();
+ if (fdio_null == nullptr) return;
+ int nullfd = fdio_bind_to_fd(fdio_null, -1, 0);
+ if (nullfd < 0) return;
+ dup2(nullfd, Fd);
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_FUCHSIA
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtilLinux.cpp b/tools/fuzzing/libfuzzer/FuzzerUtilLinux.cpp
new file mode 100644
index 0000000000..95490b992e
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtilLinux.cpp
@@ -0,0 +1,41 @@
+//===- FuzzerUtilLinux.cpp - Misc utils for Linux. ------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Misc utils for Linux.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FREEBSD || \
+ LIBFUZZER_OPENBSD || LIBFUZZER_EMSCRIPTEN
+#include "FuzzerCommand.h"
+
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+
+namespace fuzzer {
+
+int ExecuteCommand(const Command &Cmd) {
+ std::string CmdLine = Cmd.toString();
+ int exit_code = system(CmdLine.c_str());
+ if (WIFEXITED(exit_code))
+ return WEXITSTATUS(exit_code);
+ return exit_code;
+}
+
+void DiscardOutput(int Fd) {
+ FILE* Temp = fopen("/dev/null", "w");
+ if (!Temp)
+ return;
+ dup2(fileno(Temp), Fd);
+ fclose(Temp);
+}
+
+} // namespace fuzzer
+
+#endif
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtilPosix.cpp b/tools/fuzzing/libfuzzer/FuzzerUtilPosix.cpp
new file mode 100644
index 0000000000..fc57b724db
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtilPosix.cpp
@@ -0,0 +1,185 @@
+//===- FuzzerUtilPosix.cpp - Misc utils for Posix. ------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Misc utils implementation using Posix API.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_POSIX
+#include "FuzzerIO.h"
+#include "FuzzerInternal.h"
+#include "FuzzerTracePC.h"
+#include <cassert>
+#include <chrono>
+#include <cstring>
+#include <errno.h>
+#include <iomanip>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <thread>
+#include <unistd.h>
+
+namespace fuzzer {
+
+static void AlarmHandler(int, siginfo_t *, void *) {
+ Fuzzer::StaticAlarmCallback();
+}
+
+static void (*upstream_segv_handler)(int, siginfo_t *, void *);
+
+static void SegvHandler(int sig, siginfo_t *si, void *ucontext) {
+ assert(si->si_signo == SIGSEGV);
+ if (upstream_segv_handler)
+ return upstream_segv_handler(sig, si, ucontext);
+ Fuzzer::StaticCrashSignalCallback();
+}
+
+static void CrashHandler(int, siginfo_t *, void *) {
+ Fuzzer::StaticCrashSignalCallback();
+}
+
+static void InterruptHandler(int, siginfo_t *, void *) {
+ Fuzzer::StaticInterruptCallback();
+}
+
+static void GracefulExitHandler(int, siginfo_t *, void *) {
+ Fuzzer::StaticGracefulExitCallback();
+}
+
+static void FileSizeExceedHandler(int, siginfo_t *, void *) {
+ Fuzzer::StaticFileSizeExceedCallback();
+}
+
+static void SetSigaction(int signum,
+ void (*callback)(int, siginfo_t *, void *)) {
+ struct sigaction sigact = {};
+ if (sigaction(signum, nullptr, &sigact)) {
+ Printf("libFuzzer: sigaction failed with %d\n", errno);
+ exit(1);
+ }
+ if (sigact.sa_flags & SA_SIGINFO) {
+ if (sigact.sa_sigaction) {
+ if (signum != SIGSEGV)
+ return;
+ upstream_segv_handler = sigact.sa_sigaction;
+ }
+ } else {
+ if (sigact.sa_handler != SIG_DFL && sigact.sa_handler != SIG_IGN &&
+ sigact.sa_handler != SIG_ERR)
+ return;
+ }
+
+ sigact = {};
+ sigact.sa_flags = SA_SIGINFO;
+ sigact.sa_sigaction = callback;
+ if (sigaction(signum, &sigact, 0)) {
+ Printf("libFuzzer: sigaction failed with %d\n", errno);
+ exit(1);
+ }
+}
+
+// Return true on success, false otherwise.
+bool ExecuteCommand(const Command &Cmd, std::string *CmdOutput) {
+ FILE *Pipe = popen(Cmd.toString().c_str(), "r");
+ if (!Pipe)
+ return false;
+
+ if (CmdOutput) {
+ char TmpBuffer[128];
+ while (fgets(TmpBuffer, sizeof(TmpBuffer), Pipe))
+ CmdOutput->append(TmpBuffer);
+ }
+ return pclose(Pipe) == 0;
+}
+
+void SetTimer(int Seconds) {
+ struct itimerval T {
+ {Seconds, 0}, { Seconds, 0 }
+ };
+ if (setitimer(ITIMER_REAL, &T, nullptr)) {
+ Printf("libFuzzer: setitimer failed with %d\n", errno);
+ exit(1);
+ }
+ SetSigaction(SIGALRM, AlarmHandler);
+}
+
+void SetSignalHandler(const FuzzingOptions& Options) {
+ // setitimer is not implemented in emscripten.
+ if (Options.UnitTimeoutSec > 0 && !LIBFUZZER_EMSCRIPTEN)
+ SetTimer(Options.UnitTimeoutSec / 2 + 1);
+ if (Options.HandleInt)
+ SetSigaction(SIGINT, InterruptHandler);
+ if (Options.HandleTerm)
+ SetSigaction(SIGTERM, InterruptHandler);
+ if (Options.HandleSegv)
+ SetSigaction(SIGSEGV, SegvHandler);
+ if (Options.HandleBus)
+ SetSigaction(SIGBUS, CrashHandler);
+ if (Options.HandleAbrt)
+ SetSigaction(SIGABRT, CrashHandler);
+ if (Options.HandleIll)
+ SetSigaction(SIGILL, CrashHandler);
+ if (Options.HandleFpe)
+ SetSigaction(SIGFPE, CrashHandler);
+ if (Options.HandleXfsz)
+ SetSigaction(SIGXFSZ, FileSizeExceedHandler);
+ if (Options.HandleUsr1)
+ SetSigaction(SIGUSR1, GracefulExitHandler);
+ if (Options.HandleUsr2)
+ SetSigaction(SIGUSR2, GracefulExitHandler);
+}
+
+void SleepSeconds(int Seconds) {
+ sleep(Seconds); // Use C API to avoid coverage from instrumented libc++.
+}
+
+unsigned long GetPid() { return (unsigned long)getpid(); }
+
+size_t GetPeakRSSMb() {
+ struct rusage usage;
+ if (getrusage(RUSAGE_SELF, &usage))
+ return 0;
+ if (LIBFUZZER_LINUX || LIBFUZZER_FREEBSD || LIBFUZZER_NETBSD ||
+ LIBFUZZER_OPENBSD || LIBFUZZER_EMSCRIPTEN) {
+ // ru_maxrss is in KiB
+ return usage.ru_maxrss >> 10;
+ } else if (LIBFUZZER_APPLE) {
+ // ru_maxrss is in bytes
+ return usage.ru_maxrss >> 20;
+ }
+ assert(0 && "GetPeakRSSMb() is not implemented for your platform");
+ return 0;
+}
+
+FILE *OpenProcessPipe(const char *Command, const char *Mode) {
+ return popen(Command, Mode);
+}
+
+int CloseProcessPipe(FILE *F) {
+ return pclose(F);
+}
+
+const void *SearchMemory(const void *Data, size_t DataLen, const void *Patt,
+ size_t PattLen) {
+ return memmem(Data, DataLen, Patt, PattLen);
+}
+
+std::string DisassembleCmd(const std::string &FileName) {
+ return "objdump -d " + FileName;
+}
+
+std::string SearchRegexCmd(const std::string &Regex) {
+ return "grep '" + Regex + "'";
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_POSIX
diff --git a/tools/fuzzing/libfuzzer/FuzzerUtilWindows.cpp b/tools/fuzzing/libfuzzer/FuzzerUtilWindows.cpp
new file mode 100644
index 0000000000..6c693e3d7e
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerUtilWindows.cpp
@@ -0,0 +1,221 @@
+//===- FuzzerUtilWindows.cpp - Misc utils for Windows. --------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Misc utils implementation for Windows.
+//===----------------------------------------------------------------------===//
+#include "FuzzerPlatform.h"
+#if LIBFUZZER_WINDOWS
+#include "FuzzerCommand.h"
+#include "FuzzerIO.h"
+#include "FuzzerInternal.h"
+#include <cassert>
+#include <chrono>
+#include <cstring>
+#include <errno.h>
+#include <io.h>
+#include <iomanip>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <windows.h>
+
+// This must be included after windows.h.
+#include <psapi.h>
+
+namespace fuzzer {
+
+static const FuzzingOptions* HandlerOpt = nullptr;
+
+static LONG CALLBACK ExceptionHandler(PEXCEPTION_POINTERS ExceptionInfo) {
+ switch (ExceptionInfo->ExceptionRecord->ExceptionCode) {
+ case EXCEPTION_ACCESS_VIOLATION:
+ case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
+ case EXCEPTION_STACK_OVERFLOW:
+ if (HandlerOpt->HandleSegv)
+ Fuzzer::StaticCrashSignalCallback();
+ break;
+ case EXCEPTION_DATATYPE_MISALIGNMENT:
+ case EXCEPTION_IN_PAGE_ERROR:
+ if (HandlerOpt->HandleBus)
+ Fuzzer::StaticCrashSignalCallback();
+ break;
+ case EXCEPTION_ILLEGAL_INSTRUCTION:
+ case EXCEPTION_PRIV_INSTRUCTION:
+ if (HandlerOpt->HandleIll)
+ Fuzzer::StaticCrashSignalCallback();
+ break;
+ case EXCEPTION_FLT_DENORMAL_OPERAND:
+ case EXCEPTION_FLT_DIVIDE_BY_ZERO:
+ case EXCEPTION_FLT_INEXACT_RESULT:
+ case EXCEPTION_FLT_INVALID_OPERATION:
+ case EXCEPTION_FLT_OVERFLOW:
+ case EXCEPTION_FLT_STACK_CHECK:
+ case EXCEPTION_FLT_UNDERFLOW:
+ case EXCEPTION_INT_DIVIDE_BY_ZERO:
+ case EXCEPTION_INT_OVERFLOW:
+ if (HandlerOpt->HandleFpe)
+ Fuzzer::StaticCrashSignalCallback();
+ break;
+ // TODO: handle (Options.HandleXfsz)
+ }
+ return EXCEPTION_CONTINUE_SEARCH;
+}
+
+BOOL WINAPI CtrlHandler(DWORD dwCtrlType) {
+ switch (dwCtrlType) {
+ case CTRL_C_EVENT:
+ if (HandlerOpt->HandleInt)
+ Fuzzer::StaticInterruptCallback();
+ return TRUE;
+ case CTRL_BREAK_EVENT:
+ if (HandlerOpt->HandleTerm)
+ Fuzzer::StaticInterruptCallback();
+ return TRUE;
+ }
+ return FALSE;
+}
+
+void CALLBACK AlarmHandler(PVOID, BOOLEAN) {
+ Fuzzer::StaticAlarmCallback();
+}
+
+class TimerQ {
+ HANDLE TimerQueue;
+ public:
+ TimerQ() : TimerQueue(NULL) {}
+ ~TimerQ() {
+ if (TimerQueue)
+ DeleteTimerQueueEx(TimerQueue, NULL);
+ }
+ void SetTimer(int Seconds) {
+ if (!TimerQueue) {
+ TimerQueue = CreateTimerQueue();
+ if (!TimerQueue) {
+ Printf("libFuzzer: CreateTimerQueue failed.\n");
+ exit(1);
+ }
+ }
+ HANDLE Timer;
+ if (!CreateTimerQueueTimer(&Timer, TimerQueue, AlarmHandler, NULL,
+ Seconds*1000, Seconds*1000, 0)) {
+ Printf("libFuzzer: CreateTimerQueueTimer failed.\n");
+ exit(1);
+ }
+ }
+};
+
+static TimerQ Timer;
+
+static void CrashHandler(int) { Fuzzer::StaticCrashSignalCallback(); }
+
+void SetSignalHandler(const FuzzingOptions& Options) {
+ HandlerOpt = &Options;
+
+ if (Options.UnitTimeoutSec > 0)
+ Timer.SetTimer(Options.UnitTimeoutSec / 2 + 1);
+
+ if (Options.HandleInt || Options.HandleTerm)
+ if (!SetConsoleCtrlHandler(CtrlHandler, TRUE)) {
+ DWORD LastError = GetLastError();
+ Printf("libFuzzer: SetConsoleCtrlHandler failed (Error code: %lu).\n",
+ LastError);
+ exit(1);
+ }
+
+ if (Options.HandleSegv || Options.HandleBus || Options.HandleIll ||
+ Options.HandleFpe)
+ SetUnhandledExceptionFilter(ExceptionHandler);
+
+ if (Options.HandleAbrt)
+ if (SIG_ERR == signal(SIGABRT, CrashHandler)) {
+ Printf("libFuzzer: signal failed with %d\n", errno);
+ exit(1);
+ }
+}
+
+void SleepSeconds(int Seconds) { Sleep(Seconds * 1000); }
+
+unsigned long GetPid() { return GetCurrentProcessId(); }
+
+size_t GetPeakRSSMb() {
+ PROCESS_MEMORY_COUNTERS info;
+ if (!GetProcessMemoryInfo(GetCurrentProcess(), &info, sizeof(info)))
+ return 0;
+ return info.PeakWorkingSetSize >> 20;
+}
+
+FILE *OpenProcessPipe(const char *Command, const char *Mode) {
+ return _popen(Command, Mode);
+}
+
+int CloseProcessPipe(FILE *F) {
+ return _pclose(F);
+}
+
+int ExecuteCommand(const Command &Cmd) {
+ std::string CmdLine = Cmd.toString();
+ return system(CmdLine.c_str());
+}
+
+bool ExecuteCommand(const Command &Cmd, std::string *CmdOutput) {
+ FILE *Pipe = _popen(Cmd.toString().c_str(), "r");
+ if (!Pipe)
+ return false;
+
+ if (CmdOutput) {
+ char TmpBuffer[128];
+ while (fgets(TmpBuffer, sizeof(TmpBuffer), Pipe))
+ CmdOutput->append(TmpBuffer);
+ }
+ return _pclose(Pipe) == 0;
+}
+
+const void *SearchMemory(const void *Data, size_t DataLen, const void *Patt,
+ size_t PattLen) {
+ // TODO: make this implementation more efficient.
+ const char *Cdata = (const char *)Data;
+ const char *Cpatt = (const char *)Patt;
+
+ if (!Data || !Patt || DataLen == 0 || PattLen == 0 || DataLen < PattLen)
+ return NULL;
+
+ if (PattLen == 1)
+ return memchr(Data, *Cpatt, DataLen);
+
+ const char *End = Cdata + DataLen - PattLen + 1;
+
+ for (const char *It = Cdata; It < End; ++It)
+ if (It[0] == Cpatt[0] && memcmp(It, Cpatt, PattLen) == 0)
+ return It;
+
+ return NULL;
+}
+
+std::string DisassembleCmd(const std::string &FileName) {
+ Vector<std::string> command_vector;
+ command_vector.push_back("dumpbin /summary > nul");
+ if (ExecuteCommand(Command(command_vector)) == 0)
+ return "dumpbin /disasm " + FileName;
+ Printf("libFuzzer: couldn't find tool to disassemble (dumpbin)\n");
+ exit(1);
+}
+
+std::string SearchRegexCmd(const std::string &Regex) {
+ return "findstr /r \"" + Regex + "\"";
+}
+
+void DiscardOutput(int Fd) {
+ FILE* Temp = fopen("nul", "w");
+ if (!Temp)
+ return;
+ _dup2(_fileno(Temp), Fd);
+ fclose(Temp);
+}
+
+} // namespace fuzzer
+
+#endif // LIBFUZZER_WINDOWS
diff --git a/tools/fuzzing/libfuzzer/FuzzerValueBitMap.h b/tools/fuzzing/libfuzzer/FuzzerValueBitMap.h
new file mode 100644
index 0000000000..ddbfe200af
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/FuzzerValueBitMap.h
@@ -0,0 +1,73 @@
+//===- FuzzerValueBitMap.h - INTERNAL - Bit map -----------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// ValueBitMap.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_VALUE_BIT_MAP_H
+#define LLVM_FUZZER_VALUE_BIT_MAP_H
+
+#include "FuzzerPlatform.h"
+#include <cstdint>
+
+namespace fuzzer {
+
+// A bit map containing kMapSizeInWords bits.
+struct ValueBitMap {
+ static const size_t kMapSizeInBits = 1 << 16;
+ static const size_t kMapPrimeMod = 65371; // Largest Prime < kMapSizeInBits;
+ static const size_t kBitsInWord = (sizeof(uintptr_t) * 8);
+ static const size_t kMapSizeInWords = kMapSizeInBits / kBitsInWord;
+ public:
+
+ // Clears all bits.
+ void Reset() { memset(Map, 0, sizeof(Map)); }
+
+ // Computes a hash function of Value and sets the corresponding bit.
+ // Returns true if the bit was changed from 0 to 1.
+ ATTRIBUTE_NO_SANITIZE_ALL
+ inline bool AddValue(uintptr_t Value) {
+ uintptr_t Idx = Value % kMapSizeInBits;
+ uintptr_t WordIdx = Idx / kBitsInWord;
+ uintptr_t BitIdx = Idx % kBitsInWord;
+ uintptr_t Old = Map[WordIdx];
+ uintptr_t New = Old | (1ULL << BitIdx);
+ Map[WordIdx] = New;
+ return New != Old;
+ }
+
+ ATTRIBUTE_NO_SANITIZE_ALL
+ inline bool AddValueModPrime(uintptr_t Value) {
+ return AddValue(Value % kMapPrimeMod);
+ }
+
+ inline bool Get(uintptr_t Idx) {
+ assert(Idx < kMapSizeInBits);
+ uintptr_t WordIdx = Idx / kBitsInWord;
+ uintptr_t BitIdx = Idx % kBitsInWord;
+ return Map[WordIdx] & (1ULL << BitIdx);
+ }
+
+ size_t SizeInBits() const { return kMapSizeInBits; }
+
+ template <class Callback>
+ ATTRIBUTE_NO_SANITIZE_ALL
+ void ForEach(Callback CB) const {
+ for (size_t i = 0; i < kMapSizeInWords; i++)
+ if (uintptr_t M = Map[i])
+ for (size_t j = 0; j < sizeof(M) * 8; j++)
+ if (M & ((uintptr_t)1 << j))
+ CB(i * sizeof(M) * 8 + j);
+ }
+
+ private:
+ ATTRIBUTE_ALIGNED(512) uintptr_t Map[kMapSizeInWords];
+};
+
+} // namespace fuzzer
+
+#endif // LLVM_FUZZER_VALUE_BIT_MAP_H
diff --git a/tools/fuzzing/libfuzzer/LICENSE.TXT b/tools/fuzzing/libfuzzer/LICENSE.TXT
new file mode 100644
index 0000000000..555c8bb952
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/LICENSE.TXT
@@ -0,0 +1,68 @@
+==============================================================================
+LLVM Release License
+==============================================================================
+University of Illinois/NCSA
+Open Source License
+
+Copyright (c) 2003-2016 University of Illinois at Urbana-Champaign.
+All rights reserved.
+
+Developed by:
+
+ LLVM Team
+
+ University of Illinois at Urbana-Champaign
+
+ http://llvm.org
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal with
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+ * Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimers.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimers in the
+ documentation and/or other materials provided with the distribution.
+
+ * Neither the names of the LLVM Team, University of Illinois at
+ Urbana-Champaign, nor the names of its contributors may be used to
+ endorse or promote products derived from this Software without specific
+ prior written permission.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
+SOFTWARE.
+
+==============================================================================
+Copyrights and Licenses for Third Party Software Distributed with LLVM:
+==============================================================================
+The LLVM software contains code written by third parties. Such software will
+have its own individual LICENSE.TXT file in the directory in which it appears.
+This file will describe the copyrights, license, and restrictions which apply
+to that code.
+
+The disclaimer of warranty in the University of Illinois Open Source License
+applies to all code in the LLVM Distribution, and nothing in any of the
+other licenses gives permission to use the names of the LLVM Team or the
+University of Illinois to endorse or promote products derived from this
+Software.
+
+The following pieces of software have additional or alternate copyrights,
+licenses, and/or restrictions:
+
+Program Directory
+------- ---------
+Google Test llvm/utils/unittest/googletest
+OpenBSD regex llvm/lib/Support/{reg*, COPYRIGHT.regex}
+pyyaml tests llvm/test/YAMLParser/{*.data, LICENSE.TXT}
+ARM contributions llvm/lib/Target/ARM/LICENSE.TXT
+md5 contributions llvm/lib/Support/MD5.cpp llvm/include/llvm/Support/MD5.h
diff --git a/tools/fuzzing/libfuzzer/clone_libfuzzer.sh b/tools/fuzzing/libfuzzer/clone_libfuzzer.sh
new file mode 100755
index 0000000000..ca01df2978
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/clone_libfuzzer.sh
@@ -0,0 +1,36 @@
+#!/bin/bash -e
+
+# Optionally get revision from cmd line
+[ $1 ] && REVISION=$1 || REVISION=76d07503f0c69f6632e6d8d4736e2a4cb4055a92
+
+mkdir tmp
+git clone --single-branch --no-checkout --shallow-since "2020-07-01" https://github.com/llvm/llvm-project tmp
+
+(cd tmp && git reset --hard $REVISION)
+
+# libFuzzer source files
+CPPS=($(ls tmp/compiler-rt/lib/fuzzer/*.cpp | sort -r))
+CPPS=(${CPPS[@]##*/})
+CPPS=(${CPPS[@]##FuzzerMain*}) # ignored
+CPPS=(${CPPS[@]##FuzzerInterceptors*}) # ignored
+
+# Update SOURCES entries
+sed -e "/^SOURCES/,/^]/ {/'/d}" -i moz.build
+for CPP in ${CPPS[@]}; do sed -e "/^SOURCES/ a \\ '${CPP}'," -i moz.build; done
+
+# Remove previous files
+rm *.{cpp,h,def}
+
+# Copy files
+cp tmp/compiler-rt/lib/fuzzer/*.{cpp,h,def} .
+
+# Apply local patches
+for patch in patches/*.patch
+do
+ patch -p4 < $patch
+done
+
+# Remove the temporary directory
+rm -Rf tmp/
+
+echo "Updated libFuzzer to ${REVISION}"
diff --git a/tools/fuzzing/libfuzzer/moz.build b/tools/fuzzing/libfuzzer/moz.build
new file mode 100644
index 0000000000..a04169df57
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/moz.build
@@ -0,0 +1,55 @@
+# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+Library('fuzzer')
+
+EXPORTS += [
+ 'FuzzerDefs.h',
+ 'FuzzerExtFunctions.def',
+ 'FuzzerExtFunctions.h',
+]
+
+SOURCES += [
+ 'FuzzerCrossOver.cpp',
+ 'FuzzerDataFlowTrace.cpp',
+ 'FuzzerDriver.cpp',
+ 'FuzzerExtFunctionsDlsym.cpp',
+ 'FuzzerExtFunctionsWeak.cpp',
+ 'FuzzerExtFunctionsWindows.cpp',
+ 'FuzzerExtraCounters.cpp',
+ 'FuzzerFork.cpp',
+ 'FuzzerIO.cpp',
+ 'FuzzerIOPosix.cpp',
+ 'FuzzerIOWindows.cpp',
+ 'FuzzerLoop.cpp',
+ 'FuzzerMerge.cpp',
+ 'FuzzerMutate.cpp',
+ 'FuzzerSHA1.cpp',
+ 'FuzzerTracePC.cpp',
+ 'FuzzerUtil.cpp',
+ 'FuzzerUtilDarwin.cpp',
+ 'FuzzerUtilFuchsia.cpp',
+ 'FuzzerUtilLinux.cpp',
+ 'FuzzerUtilPosix.cpp',
+ 'FuzzerUtilWindows.cpp',
+]
+
+if CONFIG['CC_TYPE'] == 'clang':
+ CXXFLAGS += ['-Wno-unreachable-code-return']
+
+# According to the LLVM docs, LibFuzzer isn't supposed to be built with any
+# sanitizer flags and in fact, building it with ASan coverage currently causes
+# Clang 3.9+ to crash, so we filter out all sanitizer-related flags here.
+for flags_var in ('OS_CFLAGS', 'OS_CXXFLAGS'):
+ COMPILE_FLAGS[flags_var] = [
+ f for f in COMPILE_FLAGS.get(flags_var, [])
+ if not f.startswith('-fsanitize')
+ ]
+
+LINK_FLAGS['OS'] = [
+ f for f in LINK_FLAGS.get('OS', [])
+ if not f.startswith('-fsanitize')
+]
diff --git a/tools/fuzzing/libfuzzer/patches/10-ef-runtime.patch b/tools/fuzzing/libfuzzer/patches/10-ef-runtime.patch
new file mode 100644
index 0000000000..34562e27a5
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/patches/10-ef-runtime.patch
@@ -0,0 +1,31 @@
+# HG changeset patch
+# User Christian Holler <choller@mozilla.com>
+# Date 1596126054 -7200
+# Thu Jul 30 18:20:54 2020 +0200
+# Node ID 8a2a26b33d516c43c366b2f24d731d27d9843349
+# Parent 997c4109edd112695097fd8c55cbacd976cab24a
+[libFuzzer] Allow external functions to be defined at runtime
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerDriver.cpp b/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
+--- a/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
+@@ -608,17 +608,18 @@ static Vector<SizedFile> ReadCorpora(con
+ SizedFiles.push_back({File, Size});
+ return SizedFiles;
+ }
+
+ int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
+ using namespace fuzzer;
+ assert(argc && argv && "Argument pointers cannot be nullptr");
+ std::string Argv0((*argv)[0]);
+- EF = new ExternalFunctions();
++ if (!EF)
++ EF = new ExternalFunctions();
+ if (EF->LLVMFuzzerInitialize)
+ EF->LLVMFuzzerInitialize(argc, argv);
+ if (EF->__msan_scoped_disable_interceptor_checks)
+ EF->__msan_scoped_disable_interceptor_checks();
+ const Vector<std::string> Args(*argv, *argv + *argc);
+ assert(!Args.empty());
+ ProgName = new std::string(Args[0]);
+ if (Argv0 != *ProgName) {
diff --git a/tools/fuzzing/libfuzzer/patches/11-callback-rv.patch b/tools/fuzzing/libfuzzer/patches/11-callback-rv.patch
new file mode 100644
index 0000000000..650444442c
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/patches/11-callback-rv.patch
@@ -0,0 +1,132 @@
+# HG changeset patch
+# User Christian Holler <choller@mozilla.com>
+# Date 1596126448 -7200
+# Thu Jul 30 18:27:28 2020 +0200
+# Node ID ea198a0331a6db043cb5978512226977514104db
+# Parent 8a2a26b33d516c43c366b2f24d731d27d9843349
+[libFuzzer] Change libFuzzer callback contract to allow positive return values
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerInternal.h b/tools/fuzzing/libfuzzer/FuzzerInternal.h
+--- a/tools/fuzzing/libfuzzer/FuzzerInternal.h
++++ b/tools/fuzzing/libfuzzer/FuzzerInternal.h
+@@ -60,17 +60,17 @@ public:
+
+ static void StaticAlarmCallback();
+ static void StaticCrashSignalCallback();
+ static void StaticExitCallback();
+ static void StaticInterruptCallback();
+ static void StaticFileSizeExceedCallback();
+ static void StaticGracefulExitCallback();
+
+- void ExecuteCallback(const uint8_t *Data, size_t Size);
++ int ExecuteCallback(const uint8_t *Data, size_t Size);
+ bool RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile = false,
+ InputInfo *II = nullptr, bool *FoundUniqFeatures = nullptr);
+
+ // Merge Corpora[1:] into Corpora[0].
+ void Merge(const Vector<std::string> &Corpora);
+ void CrashResistantMergeInternalStep(const std::string &ControlFilePath);
+ MutationDispatcher &GetMD() { return MD; }
+ void PrintFinalStats();
+diff --git a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
+--- a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
+@@ -463,17 +463,19 @@ static void RenameFeatureSetFile(const s
+ DirPlusFile(FeaturesDir, NewFile));
+ }
+
+ bool Fuzzer::RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile,
+ InputInfo *II, bool *FoundUniqFeatures) {
+ if (!Size)
+ return false;
+
+- ExecuteCallback(Data, Size);
++ if (ExecuteCallback(Data, Size) > 0) {
++ return false;
++ }
+
+ UniqFeatureSetTmp.clear();
+ size_t FoundUniqFeaturesOfII = 0;
+ size_t NumUpdatesBefore = Corpus.NumFeatureUpdates();
+ TPC.CollectFeatures([&](size_t Feature) {
+ if (Corpus.AddFeature(Feature, Size, Options.Shrink))
+ UniqFeatureSetTmp.push_back(Feature);
+ if (Options.Entropic)
+@@ -530,48 +532,49 @@ static bool LooseMemeq(const uint8_t *A,
+ const size_t Limit = 64;
+ if (Size <= 64)
+ return !memcmp(A, B, Size);
+ // Compare first and last Limit/2 bytes.
+ return !memcmp(A, B, Limit / 2) &&
+ !memcmp(A + Size - Limit / 2, B + Size - Limit / 2, Limit / 2);
+ }
+
+-void Fuzzer::ExecuteCallback(const uint8_t *Data, size_t Size) {
++int Fuzzer::ExecuteCallback(const uint8_t *Data, size_t Size) {
+ TPC.RecordInitialStack();
+ TotalNumberOfRuns++;
+ assert(InFuzzingThread());
+ // We copy the contents of Unit into a separate heap buffer
+ // so that we reliably find buffer overflows in it.
+ uint8_t *DataCopy = new uint8_t[Size];
+ memcpy(DataCopy, Data, Size);
+ if (EF->__msan_unpoison)
+ EF->__msan_unpoison(DataCopy, Size);
+ if (EF->__msan_unpoison_param)
+ EF->__msan_unpoison_param(2);
+ if (CurrentUnitData && CurrentUnitData != Data)
+ memcpy(CurrentUnitData, Data, Size);
+ CurrentUnitSize = Size;
++ int Res = 0;
+ {
+ ScopedEnableMsanInterceptorChecks S;
+ AllocTracer.Start(Options.TraceMalloc);
+ UnitStartTime = system_clock::now();
+ TPC.ResetMaps();
+ RunningUserCallback = true;
+- int Res = CB(DataCopy, Size);
++ Res = CB(DataCopy, Size);
+ RunningUserCallback = false;
+ UnitStopTime = system_clock::now();
+- (void)Res;
+- assert(Res == 0);
++ assert(Res >= 0);
+ HasMoreMallocsThanFrees = AllocTracer.Stop();
+ }
+ if (!LooseMemeq(DataCopy, Data, Size))
+ CrashOnOverwrittenData();
+ CurrentUnitSize = 0;
+ delete[] DataCopy;
++ return Res;
+ }
+
+ std::string Fuzzer::WriteToOutputCorpus(const Unit &U) {
+ if (Options.OnlyASCII)
+ assert(IsASCII(U));
+ if (Options.OutputCorpus.empty())
+ return "";
+ std::string Path = DirPlusFile(Options.OutputCorpus, Hash(U));
+diff --git a/tools/fuzzing/libfuzzer/FuzzerMerge.cpp b/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
+--- a/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
+@@ -223,17 +223,19 @@ void Fuzzer::CrashResistantMergeInternal
+ U.shrink_to_fit();
+ }
+
+ // Write the pre-run marker.
+ OF << "STARTED " << i << " " << U.size() << "\n";
+ OF.flush(); // Flush is important since Command::Execute may crash.
+ // Run.
+ TPC.ResetMaps();
+- ExecuteCallback(U.data(), U.size());
++ if (ExecuteCallback(U.data(), U.size()) > 0) {
++ continue;
++ }
+ // Collect coverage. We are iterating over the files in this order:
+ // * First, files in the initial corpus ordered by size, smallest first.
+ // * Then, all other files, smallest first.
+ // So it makes no sense to record all features for all files, instead we
+ // only record features that were not seen before.
+ Set<size_t> UniqFeatures;
+ TPC.CollectFeatures([&](size_t Feature) {
+ if (AllFeatures.insert(Feature).second)
diff --git a/tools/fuzzing/libfuzzer/patches/12-custom-mutator-fail.patch b/tools/fuzzing/libfuzzer/patches/12-custom-mutator-fail.patch
new file mode 100644
index 0000000000..2457c1f046
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/patches/12-custom-mutator-fail.patch
@@ -0,0 +1,53 @@
+# HG changeset patch
+# User Christian Holler <choller@mozilla.com>
+# Date 1596126768 -7200
+# Thu Jul 30 18:32:48 2020 +0200
+# Node ID 64e7d096fa77a62b71a306b2c5383b8f75ac4945
+# Parent ea198a0331a6db043cb5978512226977514104db
+[libFuzzer] Allow custom mutators to fail
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
+--- a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
+@@ -690,16 +690,20 @@ void Fuzzer::MutateAndTestOne() {
+ if (II.HasFocusFunction && !II.DataFlowTraceForFocusFunction.empty() &&
+ Size <= CurrentMaxMutationLen)
+ NewSize = MD.MutateWithMask(CurrentUnitData, Size, Size,
+ II.DataFlowTraceForFocusFunction);
+
+ // If MutateWithMask either failed or wasn't called, call default Mutate.
+ if (!NewSize)
+ NewSize = MD.Mutate(CurrentUnitData, Size, CurrentMaxMutationLen);
++
++ if (!NewSize)
++ continue;
++
+ assert(NewSize > 0 && "Mutator returned empty unit");
+ assert(NewSize <= CurrentMaxMutationLen && "Mutator return oversized unit");
+ Size = NewSize;
+ II.NumExecutedMutations++;
+ Corpus.IncrementNumExecutedMutations();
+
+ bool FoundUniqFeatures = false;
+ bool NewCov = RunOne(CurrentUnitData, Size, /*MayDeleteFile=*/true, &II,
+@@ -850,17 +854,19 @@ void Fuzzer::Loop(Vector<SizedFile> &Cor
+ void Fuzzer::MinimizeCrashLoop(const Unit &U) {
+ if (U.size() <= 1)
+ return;
+ while (!TimedOut() && TotalNumberOfRuns < Options.MaxNumberOfRuns) {
+ MD.StartMutationSequence();
+ memcpy(CurrentUnitData, U.data(), U.size());
+ for (int i = 0; i < Options.MutateDepth; i++) {
+ size_t NewSize = MD.Mutate(CurrentUnitData, U.size(), MaxMutationLen);
+- assert(NewSize > 0 && NewSize <= MaxMutationLen);
++ assert(NewSize <= MaxMutationLen);
++ if (!NewSize)
++ continue;
+ ExecuteCallback(CurrentUnitData, NewSize);
+ PrintPulseAndReportSlowInput(CurrentUnitData, NewSize);
+ TryDetectingAMemoryLeak(CurrentUnitData, NewSize,
+ /*DuringInitialCorpusExecution*/ false);
+ }
+ }
+ }
+
diff --git a/tools/fuzzing/libfuzzer/patches/13-unused-write.patch b/tools/fuzzing/libfuzzer/patches/13-unused-write.patch
new file mode 100644
index 0000000000..f8ef7a5ac9
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/patches/13-unused-write.patch
@@ -0,0 +1,88 @@
+# HG changeset patch
+# User Christian Holler <choller@mozilla.com>
+# Date 1596126946 -7200
+# Thu Jul 30 18:35:46 2020 +0200
+# Node ID 6c779ec81530b6784a714063af66085681ab7318
+# Parent 64e7d096fa77a62b71a306b2c5383b8f75ac4945
+[libFuzzer] Suppress warnings about unused return values
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerIO.cpp b/tools/fuzzing/libfuzzer/FuzzerIO.cpp
+--- a/tools/fuzzing/libfuzzer/FuzzerIO.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerIO.cpp
+@@ -3,16 +3,17 @@
+ // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+ // See https://llvm.org/LICENSE.txt for license information.
+ // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ //
+ //===----------------------------------------------------------------------===//
+ // IO functions.
+ //===----------------------------------------------------------------------===//
+
++#include "mozilla/Unused.h"
+ #include "FuzzerDefs.h"
+ #include "FuzzerExtFunctions.h"
+ #include "FuzzerIO.h"
+ #include "FuzzerUtil.h"
+ #include <algorithm>
+ #include <cstdarg>
+ #include <fstream>
+ #include <iterator>
+@@ -68,17 +69,17 @@ void WriteToFile(const std::string &Data
+ WriteToFile(reinterpret_cast<const uint8_t *>(Data.c_str()), Data.size(),
+ Path);
+ }
+
+ void WriteToFile(const uint8_t *Data, size_t Size, const std::string &Path) {
+ // Use raw C interface because this function may be called from a sig handler.
+ FILE *Out = fopen(Path.c_str(), "wb");
+ if (!Out) return;
+- fwrite(Data, sizeof(Data[0]), Size, Out);
++ mozilla::Unused << fwrite(Data, sizeof(Data[0]), Size, Out);
+ fclose(Out);
+ }
+
+ void ReadDirToVectorOfUnits(const char *Path, Vector<Unit> *V,
+ long *Epoch, size_t MaxSize, bool ExitOnError) {
+ long E = Epoch ? *Epoch : 0;
+ Vector<std::string> Files;
+ ListFilesInDirRecursive(Path, Epoch, &Files, /*TopDir*/true);
+diff --git a/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp b/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
+--- a/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
+@@ -2,16 +2,17 @@
+ //
+ // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+ // See https://llvm.org/LICENSE.txt for license information.
+ // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ //
+ //===----------------------------------------------------------------------===//
+ // IO functions implementation using Posix API.
+ //===----------------------------------------------------------------------===//
++#include "mozilla/Unused.h"
+ #include "FuzzerPlatform.h"
+ #if LIBFUZZER_POSIX || LIBFUZZER_FUCHSIA
+
+ #include "FuzzerExtFunctions.h"
+ #include "FuzzerIO.h"
+ #include <cstdarg>
+ #include <cstdio>
+ #include <dirent.h>
+@@ -150,17 +151,17 @@ bool IsInterestingCoverageFile(const std
+ if (FileName.find("/usr/include/") != std::string::npos)
+ return false;
+ if (FileName == "<null>")
+ return false;
+ return true;
+ }
+
+ void RawPrint(const char *Str) {
+- write(2, Str, strlen(Str));
++ mozilla::Unused << write(2, Str, strlen(Str));
+ }
+
+ void MkDir(const std::string &Path) {
+ mkdir(Path.c_str(), 0700);
+ }
+
+ void RmDir(const std::string &Path) {
+ rmdir(Path.c_str());
diff --git a/tools/fuzzing/libfuzzer/patches/14-explicit-allocator.patch b/tools/fuzzing/libfuzzer/patches/14-explicit-allocator.patch
new file mode 100644
index 0000000000..8e02273193
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/patches/14-explicit-allocator.patch
@@ -0,0 +1,30 @@
+# HG changeset patch
+# User Christian Holler <choller@mozilla.com>
+# Date 1596126981 -7200
+# Thu Jul 30 18:36:21 2020 +0200
+# Node ID 069dfa3715b1d30905ff0ea1c0f66db88ce146f9
+# Parent 6c779ec81530b6784a714063af66085681ab7318
+[libFuzzer] Make fuzzer_allocator explicit
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerDefs.h b/tools/fuzzing/libfuzzer/FuzzerDefs.h
+--- a/tools/fuzzing/libfuzzer/FuzzerDefs.h
++++ b/tools/fuzzing/libfuzzer/FuzzerDefs.h
+@@ -41,17 +41,17 @@ extern ExternalFunctions *EF;
+ // We are using a custom allocator to give a different symbol name to STL
+ // containers in order to avoid ODR violations.
+ template<typename T>
+ class fuzzer_allocator: public std::allocator<T> {
+ public:
+ fuzzer_allocator() = default;
+
+ template<class U>
+- fuzzer_allocator(const fuzzer_allocator<U>&) {}
++ explicit fuzzer_allocator(const fuzzer_allocator<U>&) {}
+
+ template<class Other>
+ struct rebind { typedef fuzzer_allocator<Other> other; };
+ };
+
+ template<typename T>
+ using Vector = std::vector<T, fuzzer_allocator<T>>;
+
diff --git a/tools/fuzzing/libfuzzer/patches/15-return-to-exit.patch b/tools/fuzzing/libfuzzer/patches/15-return-to-exit.patch
new file mode 100644
index 0000000000..4adb9f59a9
--- /dev/null
+++ b/tools/fuzzing/libfuzzer/patches/15-return-to-exit.patch
@@ -0,0 +1,968 @@
+commit f80733b3b1b5e05e7dfd7a071f60050fe20108c3
+Author: Jesse Schwartzentruber <truber@mozilla.com>
+Date: Mon Mar 1 15:47:38 2021 -0500
+
+ [libfuzzer] In most cases, return instead of exit().
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp
+index 0e9cdf7e66b1..06ea287a3cfe 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.cpp
+@@ -102,9 +102,11 @@ Vector<double> BlockCoverage::FunctionWeights(size_t NumFunctions) const {
+ return Res;
+ }
+
+-void DataFlowTrace::ReadCoverage(const std::string &DirPath) {
++int DataFlowTrace::ReadCoverage(const std::string &DirPath) {
+ Vector<SizedFile> Files;
+- GetSizedFilesFromDir(DirPath, &Files);
++ int Res = GetSizedFilesFromDir(DirPath, &Files);
++ if (Res != 0)
++ return Res;
+ for (auto &SF : Files) {
+ auto Name = Basename(SF.File);
+ if (Name == kFunctionsTxt) continue;
+@@ -112,6 +114,7 @@ void DataFlowTrace::ReadCoverage(const std::string &DirPath) {
+ std::ifstream IF(SF.File);
+ Coverage.AppendCoverage(IF);
+ }
++ return 0;
+ }
+
+ static void DFTStringAppendToVector(Vector<uint8_t> *DFT,
+@@ -157,12 +160,14 @@ static bool ParseDFTLine(const std::string &Line, size_t *FunctionNum,
+ return true;
+ }
+
+-bool DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
++int DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
+ Vector<SizedFile> &CorporaFiles, Random &Rand) {
+- if (DirPath.empty()) return false;
++ if (DirPath.empty()) return 0;
+ Printf("INFO: DataFlowTrace: reading from '%s'\n", DirPath.c_str());
+ Vector<SizedFile> Files;
+- GetSizedFilesFromDir(DirPath, &Files);
++ int Res = GetSizedFilesFromDir(DirPath, &Files);
++ if (Res != 0)
++ return Res;
+ std::string L;
+ size_t FocusFuncIdx = SIZE_MAX;
+ Vector<std::string> FunctionNames;
+@@ -181,14 +186,16 @@ bool DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
+ FocusFuncIdx = NumFunctions - 1;
+ }
+ if (!NumFunctions)
+- return false;
++ return 0;
+
+ if (*FocusFunction == "auto") {
+ // AUTOFOCUS works like this:
+ // * reads the coverage data from the DFT files.
+ // * assigns weights to functions based on coverage.
+ // * chooses a random function according to the weights.
+- ReadCoverage(DirPath);
++ Res = ReadCoverage(DirPath);
++ if (Res != 0)
++ return Res;
+ auto Weights = Coverage.FunctionWeights(NumFunctions);
+ Vector<double> Intervals(NumFunctions + 1);
+ std::iota(Intervals.begin(), Intervals.end(), 0);
+@@ -209,7 +216,7 @@ bool DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
+ }
+
+ if (!NumFunctions || FocusFuncIdx == SIZE_MAX || Files.size() <= 1)
+- return false;
++ return 0;
+
+ // Read traces.
+ size_t NumTraceFiles = 0;
+@@ -228,8 +235,10 @@ bool DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
+ FunctionNum == FocusFuncIdx) {
+ NumTracesWithFocusFunction++;
+
+- if (FunctionNum >= NumFunctions)
+- return ParseError("N is greater than the number of functions", L);
++ if (FunctionNum >= NumFunctions) {
++ ParseError("N is greater than the number of functions", L);
++ return 0;
++ }
+ Traces[Name] = DFTStringToVector(DFTString);
+ // Print just a few small traces.
+ if (NumTracesWithFocusFunction <= 3 && DFTString.size() <= 16)
+@@ -241,7 +250,7 @@ bool DataFlowTrace::Init(const std::string &DirPath, std::string *FocusFunction,
+ Printf("INFO: DataFlowTrace: %zd trace files, %zd functions, "
+ "%zd traces with focus function\n",
+ NumTraceFiles, NumFunctions, NumTracesWithFocusFunction);
+- return NumTraceFiles > 0;
++ return 0;
+ }
+
+ int CollectDataFlow(const std::string &DFTBinary, const std::string &DirPath,
+diff --git a/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h
+index d6e3de30a4ef..767bad24f1d0 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h
++++ b/tools/fuzzing/libfuzzer/FuzzerDataFlowTrace.h
+@@ -113,8 +113,8 @@ class BlockCoverage {
+
+ class DataFlowTrace {
+ public:
+- void ReadCoverage(const std::string &DirPath);
+- bool Init(const std::string &DirPath, std::string *FocusFunction,
++ int ReadCoverage(const std::string &DirPath);
++ int Init(const std::string &DirPath, std::string *FocusFunction,
+ Vector<SizedFile> &CorporaFiles, Random &Rand);
+ void Clear() { Traces.clear(); }
+ const Vector<uint8_t> *Get(const std::string &InputSha1) const {
+diff --git a/tools/fuzzing/libfuzzer/FuzzerDriver.cpp b/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
+index cd720200848b..bedad16efa7b 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerDriver.cpp
+@@ -326,7 +326,7 @@ int CleanseCrashInput(const Vector<std::string> &Args,
+ if (Inputs->size() != 1 || !Flags.exact_artifact_path) {
+ Printf("ERROR: -cleanse_crash should be given one input file and"
+ " -exact_artifact_path\n");
+- exit(1);
++ return 1;
+ }
+ std::string InputFilePath = Inputs->at(0);
+ std::string OutputFilePath = Flags.exact_artifact_path;
+@@ -380,7 +380,7 @@ int MinimizeCrashInput(const Vector<std::string> &Args,
+ const FuzzingOptions &Options) {
+ if (Inputs->size() != 1) {
+ Printf("ERROR: -minimize_crash should be given one input file\n");
+- exit(1);
++ return 1;
+ }
+ std::string InputFilePath = Inputs->at(0);
+ Command BaseCmd(Args);
+@@ -411,7 +411,7 @@ int MinimizeCrashInput(const Vector<std::string> &Args,
+ bool Success = ExecuteCommand(Cmd, &CmdOutput);
+ if (Success) {
+ Printf("ERROR: the input %s did not crash\n", CurrentFilePath.c_str());
+- exit(1);
++ return 1;
+ }
+ Printf("CRASH_MIN: '%s' (%zd bytes) caused a crash. Will try to minimize "
+ "it further\n",
+@@ -466,42 +466,51 @@ int MinimizeCrashInputInternalStep(Fuzzer *F, InputCorpus *Corpus) {
+ Printf("INFO: Starting MinimizeCrashInputInternalStep: %zd\n", U.size());
+ if (U.size() < 2) {
+ Printf("INFO: The input is small enough, exiting\n");
+- exit(0);
++ return 0;
+ }
+ F->SetMaxInputLen(U.size());
+ F->SetMaxMutationLen(U.size() - 1);
+ F->MinimizeCrashLoop(U);
+ Printf("INFO: Done MinimizeCrashInputInternalStep, no crashes found\n");
+- exit(0);
+ return 0;
+ }
+
+-void Merge(Fuzzer *F, FuzzingOptions &Options, const Vector<std::string> &Args,
++int Merge(Fuzzer *F, FuzzingOptions &Options, const Vector<std::string> &Args,
+ const Vector<std::string> &Corpora, const char *CFPathOrNull) {
+ if (Corpora.size() < 2) {
+ Printf("INFO: Merge requires two or more corpus dirs\n");
+- exit(0);
++ return 0;
+ }
+
+ Vector<SizedFile> OldCorpus, NewCorpus;
+- GetSizedFilesFromDir(Corpora[0], &OldCorpus);
+- for (size_t i = 1; i < Corpora.size(); i++)
+- GetSizedFilesFromDir(Corpora[i], &NewCorpus);
++ int Res = GetSizedFilesFromDir(Corpora[0], &OldCorpus);
++ if (Res != 0)
++ return Res;
++ for (size_t i = 1; i < Corpora.size(); i++) {
++ Res = GetSizedFilesFromDir(Corpora[i], &NewCorpus);
++ if (Res != 0)
++ return Res;
++ }
+ std::sort(OldCorpus.begin(), OldCorpus.end());
+ std::sort(NewCorpus.begin(), NewCorpus.end());
+
+ std::string CFPath = CFPathOrNull ? CFPathOrNull : TempPath("Merge", ".txt");
+ Vector<std::string> NewFiles;
+ Set<uint32_t> NewFeatures, NewCov;
+- CrashResistantMerge(Args, OldCorpus, NewCorpus, &NewFiles, {}, &NewFeatures,
++ Res = CrashResistantMerge(Args, OldCorpus, NewCorpus, &NewFiles, {}, &NewFeatures,
+ {}, &NewCov, CFPath, true);
++ if (Res != 0)
++ return Res;
++
++ if (F->isGracefulExitRequested())
++ return 0;
+ for (auto &Path : NewFiles)
+ F->WriteToOutputCorpus(FileToVector(Path, Options.MaxLen));
+ // We are done, delete the control file if it was a temporary one.
+ if (!Flags.merge_control_file)
+ RemoveFile(CFPath);
+
+- exit(0);
++ return 0;
+ }
+
+ int AnalyzeDictionary(Fuzzer *F, const Vector<Unit>& Dict,
+@@ -570,10 +579,9 @@ int AnalyzeDictionary(Fuzzer *F, const Vector<Unit>& Dict,
+ return 0;
+ }
+
+-Vector<std::string> ParseSeedInuts(const char *seed_inputs) {
++int ParseSeedInuts(const char *seed_inputs, Vector<std::string> &Files) {
+ // Parse -seed_inputs=file1,file2,... or -seed_inputs=@seed_inputs_file
+- Vector<std::string> Files;
+- if (!seed_inputs) return Files;
++ if (!seed_inputs) return 0;
+ std::string SeedInputs;
+ if (Flags.seed_inputs[0] == '@')
+ SeedInputs = FileToString(Flags.seed_inputs + 1); // File contains list.
+@@ -581,7 +589,7 @@ Vector<std::string> ParseSeedInuts(const char *seed_inputs) {
+ SeedInputs = Flags.seed_inputs; // seed_inputs contains the list.
+ if (SeedInputs.empty()) {
+ Printf("seed_inputs is empty or @file does not exist.\n");
+- exit(1);
++ return 1;
+ }
+ // Parse SeedInputs.
+ size_t comma_pos = 0;
+@@ -590,7 +598,7 @@ Vector<std::string> ParseSeedInuts(const char *seed_inputs) {
+ SeedInputs = SeedInputs.substr(0, comma_pos);
+ }
+ Files.push_back(SeedInputs);
+- return Files;
++ return 0;
+ }
+
+ static Vector<SizedFile> ReadCorpora(const Vector<std::string> &CorpusDirs,
+@@ -624,7 +632,7 @@ int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
+ ProgName = new std::string(Args[0]);
+ if (Argv0 != *ProgName) {
+ Printf("ERROR: argv[0] has been modified in LLVMFuzzerInitialize\n");
+- exit(1);
++ return 1;
+ }
+ ParseFlags(Args, EF);
+ if (Flags.help) {
+@@ -723,7 +731,7 @@ int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
+ if (!Options.FocusFunction.empty()) {
+ Printf("ERROR: The parameters `--entropic` and `--focus_function` cannot "
+ "be used together.\n");
+- exit(1);
++ return 1;
+ }
+ Printf("INFO: Running with entropic power schedule (0x%X, %d).\n",
+ Options.EntropicFeatureFrequencyThreshold,
+@@ -809,22 +817,21 @@ int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
+ "*** executed the target code on a fixed set of inputs.\n"
+ "***\n");
+ F->PrintFinalStats();
+- exit(0);
++ return 0;
+ }
+
+ if (Flags.fork)
+- FuzzWithFork(F->GetMD().GetRand(), Options, Args, *Inputs, Flags.fork);
++ return FuzzWithFork(F->GetMD().GetRand(), Options, Args, *Inputs, Flags.fork);
+
+ if (Flags.merge)
+- Merge(F, Options, Args, *Inputs, Flags.merge_control_file);
++ return Merge(F, Options, Args, *Inputs, Flags.merge_control_file);
+
+ if (Flags.merge_inner) {
+ const size_t kDefaultMaxMergeLen = 1 << 20;
+ if (Options.MaxLen == 0)
+ F->SetMaxInputLen(kDefaultMaxMergeLen);
+ assert(Flags.merge_control_file);
+- F->CrashResistantMergeInternalStep(Flags.merge_control_file);
+- exit(0);
++ return F->CrashResistantMergeInternalStep(Flags.merge_control_file);
+ }
+
+ if (Flags.analyze_dict) {
+@@ -842,21 +849,31 @@ int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
+ }
+ if (AnalyzeDictionary(F, Dictionary, InitialCorpus)) {
+ Printf("Dictionary analysis failed\n");
+- exit(1);
++ return 1;
+ }
+ Printf("Dictionary analysis succeeded\n");
+- exit(0);
++ return 0;
+ }
+
+- auto CorporaFiles = ReadCorpora(*Inputs, ParseSeedInuts(Flags.seed_inputs));
+- F->Loop(CorporaFiles);
++ {
++ Vector<std::string> Files;
++ int Res = ParseSeedInuts(Flags.seed_inputs, Files);
++ if (Res != 0)
++ return Res;
++ auto CorporaFiles = ReadCorpora(*Inputs, Files);
++ Res = F->Loop(CorporaFiles);
++ if (Res != 0)
++ return Res;
++ if (F->isGracefulExitRequested())
++ return 0;
++ }
+
+ if (Flags.verbosity)
+ Printf("Done %zd runs in %zd second(s)\n", F->getTotalNumberOfRuns(),
+ F->secondsSinceProcessStartUp());
+ F->PrintFinalStats();
+
+- exit(0); // Don't let F destroy itself.
++ return 0; // Don't let F destroy itself.
+ }
+
+ extern "C" ATTRIBUTE_INTERFACE int
+diff --git a/tools/fuzzing/libfuzzer/FuzzerFork.cpp b/tools/fuzzing/libfuzzer/FuzzerFork.cpp
+index d9e6b79443e0..ee2a99a250c1 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerFork.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerFork.cpp
+@@ -177,14 +177,16 @@ struct GlobalEnv {
+ return Job;
+ }
+
+- void RunOneMergeJob(FuzzJob *Job) {
++ int RunOneMergeJob(FuzzJob *Job) {
+ auto Stats = ParseFinalStatsFromLog(Job->LogPath);
+ NumRuns += Stats.number_of_executed_units;
+
+ Vector<SizedFile> TempFiles, MergeCandidates;
+ // Read all newly created inputs and their feature sets.
+ // Choose only those inputs that have new features.
+- GetSizedFilesFromDir(Job->CorpusDir, &TempFiles);
++ int Res = GetSizedFilesFromDir(Job->CorpusDir, &TempFiles);
++ if (Res != 0)
++ return Res;
+ std::sort(TempFiles.begin(), TempFiles.end());
+ for (auto &F : TempFiles) {
+ auto FeatureFile = F.File;
+@@ -207,12 +209,14 @@ struct GlobalEnv {
+ Stats.average_exec_per_sec, NumOOMs, NumTimeouts, NumCrashes,
+ secondsSinceProcessStartUp(), Job->JobId, Job->DftTimeInSeconds);
+
+- if (MergeCandidates.empty()) return;
++ if (MergeCandidates.empty()) return 0;
+
+ Vector<std::string> FilesToAdd;
+ Set<uint32_t> NewFeatures, NewCov;
+ CrashResistantMerge(Args, {}, MergeCandidates, &FilesToAdd, Features,
+ &NewFeatures, Cov, &NewCov, Job->CFPath, false);
++ if (Fuzzer::isGracefulExitRequested())
++ return 0;
+ for (auto &Path : FilesToAdd) {
+ auto U = FileToVector(Path);
+ auto NewPath = DirPlusFile(MainCorpusDir, Hash(U));
+@@ -226,7 +230,7 @@ struct GlobalEnv {
+ if (TPC.PcIsFuncEntry(TE))
+ PrintPC(" NEW_FUNC: %p %F %L\n", "",
+ TPC.GetNextInstructionPc(TE->PC));
+-
++ return 0;
+ }
+
+
+@@ -280,7 +284,7 @@ void WorkerThread(JobQueue *FuzzQ, JobQueue *MergeQ) {
+ }
+
+ // This is just a skeleton of an experimental -fork=1 feature.
+-void FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
++int FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ const Vector<std::string> &Args,
+ const Vector<std::string> &CorpusDirs, int NumJobs) {
+ Printf("INFO: -fork=%d: fuzzing in separate process(s)\n", NumJobs);
+@@ -294,8 +298,12 @@ void FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ Env.DataFlowBinary = Options.CollectDataFlow;
+
+ Vector<SizedFile> SeedFiles;
+- for (auto &Dir : CorpusDirs)
+- GetSizedFilesFromDir(Dir, &SeedFiles);
++ int Res;
++ for (auto &Dir : CorpusDirs) {
++ Res = GetSizedFilesFromDir(Dir, &SeedFiles);
++ if (Res != 0)
++ return Res;
++ }
+ std::sort(SeedFiles.begin(), SeedFiles.end());
+ Env.TempDir = TempPath("FuzzWithFork", ".dir");
+ Env.DFTDir = DirPlusFile(Env.TempDir, "DFT");
+@@ -310,9 +318,14 @@ void FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ Env.MainCorpusDir = CorpusDirs[0];
+
+ auto CFPath = DirPlusFile(Env.TempDir, "merge.txt");
+- CrashResistantMerge(Env.Args, {}, SeedFiles, &Env.Files, {}, &Env.Features,
++ Res = CrashResistantMerge(Env.Args, {}, SeedFiles, &Env.Files, {}, &Env.Features,
+ {}, &Env.Cov,
+ CFPath, false);
++ if (Res != 0)
++ return Res;
++ if (Fuzzer::isGracefulExitRequested())
++ return 0;
++
+ RemoveFile(CFPath);
+ Printf("INFO: -fork=%d: %zd seed inputs, starting to fuzz in %s\n", NumJobs,
+ Env.Files.size(), Env.TempDir.c_str());
+@@ -345,9 +358,14 @@ void FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ StopJobs();
+ break;
+ }
+- Fuzzer::MaybeExitGracefully();
++ if (Fuzzer::MaybeExitGracefully())
++ return 0;
+
+- Env.RunOneMergeJob(Job.get());
++ Res = Env.RunOneMergeJob(Job.get());
++ if (Res != 0)
++ return Res;
++ if (Fuzzer::isGracefulExitRequested())
++ return 0;
+
+ // Continue if our crash is one of the ignorred ones.
+ if (Options.IgnoreTimeouts && ExitCode == Options.TimeoutExitCode)
+@@ -403,7 +421,7 @@ void FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ // Use the exit code from the last child process.
+ Printf("INFO: exiting: %d time: %zds\n", ExitCode,
+ Env.secondsSinceProcessStartUp());
+- exit(ExitCode);
++ return ExitCode;
+ }
+
+ } // namespace fuzzer
+diff --git a/tools/fuzzing/libfuzzer/FuzzerFork.h b/tools/fuzzing/libfuzzer/FuzzerFork.h
+index b29a43e13fbc..1352171ad49d 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerFork.h
++++ b/tools/fuzzing/libfuzzer/FuzzerFork.h
+@@ -16,7 +16,7 @@
+ #include <string>
+
+ namespace fuzzer {
+-void FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
++int FuzzWithFork(Random &Rand, const FuzzingOptions &Options,
+ const Vector<std::string> &Args,
+ const Vector<std::string> &CorpusDirs, int NumJobs);
+ } // namespace fuzzer
+diff --git a/tools/fuzzing/libfuzzer/FuzzerIO.cpp b/tools/fuzzing/libfuzzer/FuzzerIO.cpp
+index 0053ef39f2b9..6be2be67c691 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerIO.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerIO.cpp
+@@ -82,7 +82,9 @@ void ReadDirToVectorOfUnits(const char *Path, Vector<Unit> *V,
+ long *Epoch, size_t MaxSize, bool ExitOnError) {
+ long E = Epoch ? *Epoch : 0;
+ Vector<std::string> Files;
+- ListFilesInDirRecursive(Path, Epoch, &Files, /*TopDir*/true);
++ int Res = ListFilesInDirRecursive(Path, Epoch, &Files, /*TopDir*/true);
++ if (ExitOnError && Res != 0)
++ exit(Res);
+ size_t NumLoaded = 0;
+ for (size_t i = 0; i < Files.size(); i++) {
+ auto &X = Files[i];
+@@ -97,12 +99,15 @@ void ReadDirToVectorOfUnits(const char *Path, Vector<Unit> *V,
+ }
+
+
+-void GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V) {
++int GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V) {
+ Vector<std::string> Files;
+- ListFilesInDirRecursive(Dir, 0, &Files, /*TopDir*/true);
++ int Res = ListFilesInDirRecursive(Dir, 0, &Files, /*TopDir*/true);
++ if (Res != 0)
++ return Res;
+ for (auto &File : Files)
+ if (size_t Size = FileSize(File))
+ V->push_back({File, Size});
++ return 0;
+ }
+
+ std::string DirPlusFile(const std::string &DirPath,
+diff --git a/tools/fuzzing/libfuzzer/FuzzerIO.h b/tools/fuzzing/libfuzzer/FuzzerIO.h
+index 6e4368b971fa..6c90ba637322 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerIO.h
++++ b/tools/fuzzing/libfuzzer/FuzzerIO.h
+@@ -60,7 +60,7 @@ void RawPrint(const char *Str);
+ bool IsFile(const std::string &Path);
+ size_t FileSize(const std::string &Path);
+
+-void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
++int ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ Vector<std::string> *V, bool TopDir);
+
+ void RmDirRecursive(const std::string &Dir);
+@@ -79,7 +79,7 @@ struct SizedFile {
+ bool operator<(const SizedFile &B) const { return Size < B.Size; }
+ };
+
+-void GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V);
++int GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V);
+
+ char GetSeparator();
+ // Similar to the basename utility: returns the file name w/o the dir prefix.
+diff --git a/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp b/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
+index 4b453d286c80..1a50295c010f 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerIOPosix.cpp
+@@ -53,16 +53,16 @@ std::string Basename(const std::string &Path) {
+ return Path.substr(Pos + 1);
+ }
+
+-void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
++int ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ Vector<std::string> *V, bool TopDir) {
+ auto E = GetEpoch(Dir);
+ if (Epoch)
+- if (E && *Epoch >= E) return;
++ if (E && *Epoch >= E) return 0;
+
+ DIR *D = opendir(Dir.c_str());
+ if (!D) {
+ Printf("%s: %s; exiting\n", strerror(errno), Dir.c_str());
+- exit(1);
++ return 1;
+ }
+ while (auto E = readdir(D)) {
+ std::string Path = DirPlusFile(Dir, E->d_name);
+@@ -71,12 +71,16 @@ void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ V->push_back(Path);
+ else if ((E->d_type == DT_DIR ||
+ (E->d_type == DT_UNKNOWN && IsDirectory(Path))) &&
+- *E->d_name != '.')
+- ListFilesInDirRecursive(Path, Epoch, V, false);
++ *E->d_name != '.') {
++ int Res = ListFilesInDirRecursive(Path, Epoch, V, false);
++ if (Res != 0)
++ return Res;
++ }
+ }
+ closedir(D);
+ if (Epoch && TopDir)
+ *Epoch = E;
++ return 0;
+ }
+
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp b/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp
+index 651283a551cf..0e977bd02557 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerIOWindows.cpp
+@@ -98,11 +98,12 @@ size_t FileSize(const std::string &Path) {
+ return size.QuadPart;
+ }
+
+-void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
++int ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ Vector<std::string> *V, bool TopDir) {
++ int Res;
+ auto E = GetEpoch(Dir);
+ if (Epoch)
+- if (E && *Epoch >= E) return;
++ if (E && *Epoch >= E) return 0;
+
+ std::string Path(Dir);
+ assert(!Path.empty());
+@@ -116,9 +117,9 @@ void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ if (FindHandle == INVALID_HANDLE_VALUE)
+ {
+ if (GetLastError() == ERROR_FILE_NOT_FOUND)
+- return;
++ return 0;
+ Printf("No such file or directory: %s; exiting\n", Dir.c_str());
+- exit(1);
++ return 1;
+ }
+
+ do {
+@@ -131,7 +132,9 @@ void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+ FindInfo.cFileName[1] == '.'))
+ continue;
+
+- ListFilesInDirRecursive(FileName, Epoch, V, false);
++ int Res = ListFilesInDirRecursive(FileName, Epoch, V, false);
++ if (Res != 0)
++ return Res;
+ }
+ else if (IsFile(FileName, FindInfo.dwFileAttributes))
+ V->push_back(FileName);
+@@ -145,6 +148,7 @@ void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+
+ if (Epoch && TopDir)
+ *Epoch = E;
++ return 0;
+ }
+
+
+diff --git a/tools/fuzzing/libfuzzer/FuzzerInternal.h b/tools/fuzzing/libfuzzer/FuzzerInternal.h
+index 1f7d671ed848..cc2650b58ef1 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerInternal.h
++++ b/tools/fuzzing/libfuzzer/FuzzerInternal.h
+@@ -35,8 +35,8 @@ public:
+ Fuzzer(UserCallback CB, InputCorpus &Corpus, MutationDispatcher &MD,
+ FuzzingOptions Options);
+ ~Fuzzer();
+- void Loop(Vector<SizedFile> &CorporaFiles);
+- void ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles);
++ int Loop(Vector<SizedFile> &CorporaFiles);
++ int ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles);
+ void MinimizeCrashLoop(const Unit &U);
+ void RereadOutputCorpus(size_t MaxSize);
+
+@@ -65,13 +65,16 @@ public:
+ static void StaticFileSizeExceedCallback();
+ static void StaticGracefulExitCallback();
+
++ static void GracefullyExit();
++ static bool isGracefulExitRequested();
++
+ int ExecuteCallback(const uint8_t *Data, size_t Size);
+ bool RunOne(const uint8_t *Data, size_t Size, bool MayDeleteFile = false,
+ InputInfo *II = nullptr, bool *FoundUniqFeatures = nullptr);
+
+ // Merge Corpora[1:] into Corpora[0].
+ void Merge(const Vector<std::string> &Corpora);
+- void CrashResistantMergeInternalStep(const std::string &ControlFilePath);
++ int CrashResistantMergeInternalStep(const std::string &ControlFilePath);
+ MutationDispatcher &GetMD() { return MD; }
+ void PrintFinalStats();
+ void SetMaxInputLen(size_t MaxInputLen);
+@@ -84,7 +87,7 @@ public:
+ bool DuringInitialCorpusExecution);
+
+ void HandleMalloc(size_t Size);
+- static void MaybeExitGracefully();
++ static bool MaybeExitGracefully();
+ std::string WriteToOutputCorpus(const Unit &U);
+
+ private:
+@@ -93,7 +96,7 @@ private:
+ void ExitCallback();
+ void CrashOnOverwrittenData();
+ void InterruptCallback();
+- void MutateAndTestOne();
++ bool MutateAndTestOne();
+ void PurgeAllocator();
+ void ReportNewCoverage(InputInfo *II, const Unit &U);
+ void PrintPulseAndReportSlowInput(const uint8_t *Data, size_t Size);
+diff --git a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
+index 4c4e8c271b1f..e7dfc187dbfe 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerLoop.cpp
+@@ -254,12 +254,20 @@ void Fuzzer::ExitCallback() {
+ _Exit(Options.ErrorExitCode);
+ }
+
+-void Fuzzer::MaybeExitGracefully() {
+- if (!F->GracefulExitRequested) return;
++bool Fuzzer::MaybeExitGracefully() {
++ if (!F->GracefulExitRequested) return false;
+ Printf("==%lu== INFO: libFuzzer: exiting as requested\n", GetPid());
+ RmDirRecursive(TempPath("FuzzWithFork", ".dir"));
+ F->PrintFinalStats();
+- _Exit(0);
++ return true;
++}
++
++void Fuzzer::GracefullyExit() {
++ F->GracefulExitRequested = true;
++}
++
++bool Fuzzer::isGracefulExitRequested() {
++ return F->GracefulExitRequested;
+ }
+
+ void Fuzzer::InterruptCallback() {
+@@ -663,7 +671,7 @@ void Fuzzer::TryDetectingAMemoryLeak(const uint8_t *Data, size_t Size,
+ }
+ }
+
+-void Fuzzer::MutateAndTestOne() {
++bool Fuzzer::MutateAndTestOne() {
+ MD.StartMutationSequence();
+
+ auto &II = Corpus.ChooseUnitToMutate(MD.GetRand());
+@@ -685,7 +693,7 @@ void Fuzzer::MutateAndTestOne() {
+ for (int i = 0; i < Options.MutateDepth; i++) {
+ if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+ break;
+- MaybeExitGracefully();
++ if (MaybeExitGracefully()) return true;
+ size_t NewSize = 0;
+ if (II.HasFocusFunction && !II.DataFlowTraceForFocusFunction.empty() &&
+ Size <= CurrentMaxMutationLen)
+@@ -719,6 +727,7 @@ void Fuzzer::MutateAndTestOne() {
+ }
+
+ II.NeedsEnergyUpdate = true;
++ return false;
+ }
+
+ void Fuzzer::PurgeAllocator() {
+@@ -736,7 +745,7 @@ void Fuzzer::PurgeAllocator() {
+ LastAllocatorPurgeAttemptTime = system_clock::now();
+ }
+
+-void Fuzzer::ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles) {
++int Fuzzer::ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles) {
+ const size_t kMaxSaneLen = 1 << 20;
+ const size_t kMinDefaultLen = 4096;
+ size_t MaxSize = 0;
+@@ -795,16 +804,23 @@ void Fuzzer::ReadAndExecuteSeedCorpora(Vector<SizedFile> &CorporaFiles) {
+ if (Corpus.empty() && Options.MaxNumberOfRuns) {
+ Printf("ERROR: no interesting inputs were found. "
+ "Is the code instrumented for coverage? Exiting.\n");
+- exit(1);
++ return 1;
+ }
++ return 0;
+ }
+
+-void Fuzzer::Loop(Vector<SizedFile> &CorporaFiles) {
++int Fuzzer::Loop(Vector<SizedFile> &CorporaFiles) {
+ auto FocusFunctionOrAuto = Options.FocusFunction;
+- DFT.Init(Options.DataFlowTrace, &FocusFunctionOrAuto, CorporaFiles,
++ int Res = DFT.Init(Options.DataFlowTrace, &FocusFunctionOrAuto, CorporaFiles,
+ MD.GetRand());
+- TPC.SetFocusFunction(FocusFunctionOrAuto);
+- ReadAndExecuteSeedCorpora(CorporaFiles);
++ if (Res != 0)
++ return Res;
++ Res = TPC.SetFocusFunction(FocusFunctionOrAuto);
++ if (Res != 0)
++ return Res;
++ Res = ReadAndExecuteSeedCorpora(CorporaFiles);
++ if (Res != 0)
++ return Res;
+ DFT.Clear(); // No need for DFT any more.
+ TPC.SetPrintNewPCs(Options.PrintNewCovPcs);
+ TPC.SetPrintNewFuncs(Options.PrintNewCovFuncs);
+@@ -842,13 +858,15 @@ void Fuzzer::Loop(Vector<SizedFile> &CorporaFiles) {
+ }
+
+ // Perform several mutations and runs.
+- MutateAndTestOne();
++ if (MutateAndTestOne())
++ return 0;
+
+ PurgeAllocator();
+ }
+
+ PrintStats("DONE ", "\n");
+ MD.PrintRecommendedDictionary();
++ return 0;
+ }
+
+ void Fuzzer::MinimizeCrashLoop(const Unit &U) {
+diff --git a/tools/fuzzing/libfuzzer/FuzzerMerge.cpp b/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
+index 919eea848580..0a185c7325bb 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerMerge.cpp
+@@ -28,11 +28,12 @@ bool Merger::Parse(const std::string &Str, bool ParseCoverage) {
+ return Parse(SS, ParseCoverage);
+ }
+
+-void Merger::ParseOrExit(std::istream &IS, bool ParseCoverage) {
++int Merger::ParseOrExit(std::istream &IS, bool ParseCoverage) {
+ if (!Parse(IS, ParseCoverage)) {
+ Printf("MERGE: failed to parse the control file (unexpected error)\n");
+- exit(1);
++ return 1;
+ }
++ return 0;
+ }
+
+ // The control file example:
+@@ -194,11 +195,13 @@ Set<uint32_t> Merger::AllFeatures() const {
+ }
+
+ // Inner process. May crash if the target crashes.
+-void Fuzzer::CrashResistantMergeInternalStep(const std::string &CFPath) {
++int Fuzzer::CrashResistantMergeInternalStep(const std::string &CFPath) {
+ Printf("MERGE-INNER: using the control file '%s'\n", CFPath.c_str());
+ Merger M;
+ std::ifstream IF(CFPath);
+- M.ParseOrExit(IF, false);
++ int Res = M.ParseOrExit(IF, false);
++ if (Res != 0)
++ return Res;
+ IF.close();
+ if (!M.LastFailure.empty())
+ Printf("MERGE-INNER: '%s' caused a failure at the previous merge step\n",
+@@ -216,7 +219,8 @@ void Fuzzer::CrashResistantMergeInternalStep(const std::string &CFPath) {
+ };
+ Set<const TracePC::PCTableEntry *> AllPCs;
+ for (size_t i = M.FirstNotProcessedFile; i < M.Files.size(); i++) {
+- Fuzzer::MaybeExitGracefully();
++ if (Fuzzer::MaybeExitGracefully())
++ return 0;
+ auto U = FileToVector(M.Files[i].Name);
+ if (U.size() > MaxInputLen) {
+ U.resize(MaxInputLen);
+@@ -261,12 +265,14 @@ void Fuzzer::CrashResistantMergeInternalStep(const std::string &CFPath) {
+ OF.flush();
+ }
+ PrintStatsWrapper("DONE ");
++ return 0;
+ }
+
+-static size_t WriteNewControlFile(const std::string &CFPath,
++static int WriteNewControlFile(const std::string &CFPath,
+ const Vector<SizedFile> &OldCorpus,
+ const Vector<SizedFile> &NewCorpus,
+- const Vector<MergeFileInfo> &KnownFiles) {
++ const Vector<MergeFileInfo> &KnownFiles,
++ size_t &NumFiles) {
+ std::unordered_set<std::string> FilesToSkip;
+ for (auto &SF: KnownFiles)
+ FilesToSkip.insert(SF.Name);
+@@ -292,14 +298,15 @@ static size_t WriteNewControlFile(const std::string &CFPath,
+ if (!ControlFile) {
+ Printf("MERGE-OUTER: failed to write to the control file: %s\n",
+ CFPath.c_str());
+- exit(1);
++ return 1;
+ }
+
+- return FilesToUse.size();
++ NumFiles = FilesToUse.size();
++ return 0;
+ }
+
+ // Outer process. Does not call the target code and thus should not fail.
+-void CrashResistantMerge(const Vector<std::string> &Args,
++int CrashResistantMerge(const Vector<std::string> &Args,
+ const Vector<SizedFile> &OldCorpus,
+ const Vector<SizedFile> &NewCorpus,
+ Vector<std::string> *NewFiles,
+@@ -309,8 +316,9 @@ void CrashResistantMerge(const Vector<std::string> &Args,
+ Set<uint32_t> *NewCov,
+ const std::string &CFPath,
+ bool V /*Verbose*/) {
+- if (NewCorpus.empty() && OldCorpus.empty()) return; // Nothing to merge.
++ if (NewCorpus.empty() && OldCorpus.empty()) return 0; // Nothing to merge.
+ size_t NumAttempts = 0;
++ int Res;
+ Vector<MergeFileInfo> KnownFiles;
+ if (FileSize(CFPath)) {
+ VPrintf(V, "MERGE-OUTER: non-empty control file provided: '%s'\n",
+@@ -331,7 +339,8 @@ void CrashResistantMerge(const Vector<std::string> &Args,
+ VPrintf(
+ V,
+ "MERGE-OUTER: nothing to do, merge has been completed before\n");
+- exit(0);
++ Fuzzer::GracefullyExit();
++ return 0;
+ }
+
+ // Number of input files likely changed, start merge from scratch, but
+@@ -356,7 +365,9 @@ void CrashResistantMerge(const Vector<std::string> &Args,
+ "%zd files, %zd in the initial corpus, %zd processed earlier\n",
+ OldCorpus.size() + NewCorpus.size(), OldCorpus.size(),
+ KnownFiles.size());
+- NumAttempts = WriteNewControlFile(CFPath, OldCorpus, NewCorpus, KnownFiles);
++ Res = WriteNewControlFile(CFPath, OldCorpus, NewCorpus, KnownFiles, NumAttempts);
++ if (Res != 0)
++ return Res;
+ }
+
+ // Execute the inner process until it passes.
+@@ -366,7 +377,8 @@ void CrashResistantMerge(const Vector<std::string> &Args,
+ BaseCmd.removeFlag("fork");
+ BaseCmd.removeFlag("collect_data_flow");
+ for (size_t Attempt = 1; Attempt <= NumAttempts; Attempt++) {
+- Fuzzer::MaybeExitGracefully();
++ if (Fuzzer::MaybeExitGracefully())
++ return 0;
+ VPrintf(V, "MERGE-OUTER: attempt %zd\n", Attempt);
+ Command Cmd(BaseCmd);
+ Cmd.addFlag("merge_control_file", CFPath);
+@@ -388,7 +400,9 @@ void CrashResistantMerge(const Vector<std::string> &Args,
+ VPrintf(V, "MERGE-OUTER: the control file has %zd bytes\n",
+ (size_t)IF.tellg());
+ IF.seekg(0, IF.beg);
+- M.ParseOrExit(IF, true);
++ Res = M.ParseOrExit(IF, true);
++ if (Res != 0)
++ return Res;
+ IF.close();
+ VPrintf(V,
+ "MERGE-OUTER: consumed %zdMb (%zdMb rss) to parse the control file\n",
+@@ -399,6 +413,7 @@ void CrashResistantMerge(const Vector<std::string> &Args,
+ VPrintf(V, "MERGE-OUTER: %zd new files with %zd new features added; "
+ "%zd new coverage edges\n",
+ NewFiles->size(), NewFeatures->size(), NewCov->size());
++ return 0;
+ }
+
+ } // namespace fuzzer
+diff --git a/tools/fuzzing/libfuzzer/FuzzerMerge.h b/tools/fuzzing/libfuzzer/FuzzerMerge.h
+index e0c6bc539bdb..6dc1c4c45abf 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerMerge.h
++++ b/tools/fuzzing/libfuzzer/FuzzerMerge.h
+@@ -63,7 +63,7 @@ struct Merger {
+
+ bool Parse(std::istream &IS, bool ParseCoverage);
+ bool Parse(const std::string &Str, bool ParseCoverage);
+- void ParseOrExit(std::istream &IS, bool ParseCoverage);
++ int ParseOrExit(std::istream &IS, bool ParseCoverage);
+ size_t Merge(const Set<uint32_t> &InitialFeatures, Set<uint32_t> *NewFeatures,
+ const Set<uint32_t> &InitialCov, Set<uint32_t> *NewCov,
+ Vector<std::string> *NewFiles);
+@@ -71,7 +71,7 @@ struct Merger {
+ Set<uint32_t> AllFeatures() const;
+ };
+
+-void CrashResistantMerge(const Vector<std::string> &Args,
++int CrashResistantMerge(const Vector<std::string> &Args,
+ const Vector<SizedFile> &OldCorpus,
+ const Vector<SizedFile> &NewCorpus,
+ Vector<std::string> *NewFiles,
+diff --git a/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp b/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp
+index b2ca7693e540..fbceda39bc22 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp
++++ b/tools/fuzzing/libfuzzer/FuzzerTracePC.cpp
+@@ -238,13 +238,13 @@ void TracePC::IterateCoveredFunctions(CallBack CB) {
+ }
+ }
+
+-void TracePC::SetFocusFunction(const std::string &FuncName) {
++int TracePC::SetFocusFunction(const std::string &FuncName) {
+ // This function should be called once.
+ assert(!FocusFunctionCounterPtr);
+ // "auto" is not a valid function name. If this function is called with "auto"
+ // that means the auto focus functionality failed.
+ if (FuncName.empty() || FuncName == "auto")
+- return;
++ return 0;
+ for (size_t M = 0; M < NumModules; M++) {
+ auto &PCTE = ModulePCTable[M];
+ size_t N = PCTE.Stop - PCTE.Start;
+@@ -256,13 +256,13 @@ void TracePC::SetFocusFunction(const std::string &FuncName) {
+ if (FuncName != Name) continue;
+ Printf("INFO: Focus function is set to '%s'\n", Name.c_str());
+ FocusFunctionCounterPtr = Modules[M].Start() + I;
+- return;
++ return 0;
+ }
+ }
+
+ Printf("ERROR: Failed to set focus function. Make sure the function name is "
+ "valid (%s) and symbolization is enabled.\n", FuncName.c_str());
+- exit(1);
++ return 1;
+ }
+
+ bool TracePC::ObservedFocusFunction() {
+diff --git a/tools/fuzzing/libfuzzer/FuzzerTracePC.h b/tools/fuzzing/libfuzzer/FuzzerTracePC.h
+index 501f3b544971..b46ebb909dbf 100644
+--- a/tools/fuzzing/libfuzzer/FuzzerTracePC.h
++++ b/tools/fuzzing/libfuzzer/FuzzerTracePC.h
+@@ -116,7 +116,7 @@ class TracePC {
+ CB(PC);
+ }
+
+- void SetFocusFunction(const std::string &FuncName);
++ int SetFocusFunction(const std::string &FuncName);
+ bool ObservedFocusFunction();
+
+ struct PCTableEntry {