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Diffstat (limited to 'toolkit/crashreporter/google-breakpad/src/processor/stackwalker_arm_unittest.cc')
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diff --git a/toolkit/crashreporter/google-breakpad/src/processor/stackwalker_arm_unittest.cc b/toolkit/crashreporter/google-breakpad/src/processor/stackwalker_arm_unittest.cc new file mode 100644 index 0000000000..256f7648c4 --- /dev/null +++ b/toolkit/crashreporter/google-breakpad/src/processor/stackwalker_arm_unittest.cc @@ -0,0 +1,979 @@ +// Copyright (c) 2010, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com> + +// stackwalker_arm_unittest.cc: Unit tests for StackwalkerARM class. + +#include <string.h> +#include <string> +#include <vector> + +#include "breakpad_googletest_includes.h" +#include "common/test_assembler.h" +#include "common/using_std_string.h" +#include "google_breakpad/common/minidump_format.h" +#include "google_breakpad/processor/basic_source_line_resolver.h" +#include "google_breakpad/processor/call_stack.h" +#include "google_breakpad/processor/code_module.h" +#include "google_breakpad/processor/source_line_resolver_interface.h" +#include "google_breakpad/processor/stack_frame_cpu.h" +#include "processor/stackwalker_unittest_utils.h" +#include "processor/stackwalker_arm.h" +#include "processor/windows_frame_info.h" + +using google_breakpad::BasicSourceLineResolver; +using google_breakpad::CallStack; +using google_breakpad::CodeModule; +using google_breakpad::StackFrameSymbolizer; +using google_breakpad::StackFrame; +using google_breakpad::StackFrameARM; +using google_breakpad::Stackwalker; +using google_breakpad::StackwalkerARM; +using google_breakpad::SystemInfo; +using google_breakpad::WindowsFrameInfo; +using google_breakpad::test_assembler::kLittleEndian; +using google_breakpad::test_assembler::Label; +using google_breakpad::test_assembler::Section; +using std::vector; +using testing::_; +using testing::AnyNumber; +using testing::DoAll; +using testing::Return; +using testing::SetArgumentPointee; +using testing::Test; + +class StackwalkerARMFixture { + public: + StackwalkerARMFixture() + : stack_section(kLittleEndian), + // Give the two modules reasonable standard locations and names + // for tests to play with. + module1(0x40000000, 0x10000, "module1", "version1"), + module2(0x50000000, 0x10000, "module2", "version2") { + // Identify the system as a Linux system. + system_info.os = "Linux"; + system_info.os_short = "linux"; + system_info.os_version = "Lugubrious Labrador"; + system_info.cpu = "arm"; + system_info.cpu_info = ""; + + // Put distinctive values in the raw CPU context. + BrandContext(&raw_context); + + // Create some modules with some stock debugging information. + modules.Add(&module1); + modules.Add(&module2); + + // By default, none of the modules have symbol info; call + // SetModuleSymbols to override this. + EXPECT_CALL(supplier, GetCStringSymbolData(_, _, _, _, _)) + .WillRepeatedly(Return(MockSymbolSupplier::NOT_FOUND)); + + // Avoid GMOCK WARNING "Uninteresting mock function call - returning + // directly" for FreeSymbolData(). + EXPECT_CALL(supplier, FreeSymbolData(_)).Times(AnyNumber()); + + // Reset max_frames_scanned since it's static. + Stackwalker::set_max_frames_scanned(1024); + } + + // Set the Breakpad symbol information that supplier should return for + // MODULE to INFO. + void SetModuleSymbols(MockCodeModule *module, const string &info) { + size_t buffer_size; + char *buffer = supplier.CopySymbolDataAndOwnTheCopy(info, &buffer_size); + EXPECT_CALL(supplier, GetCStringSymbolData(module, &system_info, _, _, _)) + .WillRepeatedly(DoAll(SetArgumentPointee<3>(buffer), + SetArgumentPointee<4>(buffer_size), + Return(MockSymbolSupplier::FOUND))); + } + + // Populate stack_region with the contents of stack_section. Use + // stack_section.start() as the region's starting address. + void RegionFromSection() { + string contents; + ASSERT_TRUE(stack_section.GetContents(&contents)); + stack_region.Init(stack_section.start().Value(), contents); + } + + // Fill RAW_CONTEXT with pseudo-random data, for round-trip checking. + void BrandContext(MDRawContextARM *raw_context) { + uint8_t x = 173; + for (size_t i = 0; i < sizeof(*raw_context); i++) + reinterpret_cast<uint8_t *>(raw_context)[i] = (x += 17); + } + + SystemInfo system_info; + MDRawContextARM raw_context; + Section stack_section; + MockMemoryRegion stack_region; + MockCodeModule module1; + MockCodeModule module2; + MockCodeModules modules; + MockSymbolSupplier supplier; + BasicSourceLineResolver resolver; + CallStack call_stack; + const vector<StackFrame *> *frames; +}; + +class SanityCheck: public StackwalkerARMFixture, public Test { }; + +TEST_F(SanityCheck, NoResolver) { + // Since we have no call frame information, and all unwinding + // requires call frame information, the stack walk will end after + // the first frame. + StackFrameSymbolizer frame_symbolizer(NULL, NULL); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + // This should succeed even without a resolver or supplier. + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(1U, frames->size()); + StackFrameARM *frame = static_cast<StackFrameARM *>(frames->at(0)); + // Check that the values from the original raw context made it + // through to the context in the stack frame. + EXPECT_EQ(0, memcmp(&raw_context, &frame->context, sizeof(raw_context))); +} + +class GetContextFrame: public StackwalkerARMFixture, public Test { }; + +TEST_F(GetContextFrame, Simple) { + // Since we have no call frame information, and all unwinding + // requires call frame information, the stack walk will end after + // the first frame. + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(1U, frames->size()); + StackFrameARM *frame = static_cast<StackFrameARM *>(frames->at(0)); + // Check that the values from the original raw context made it + // through to the context in the stack frame. + EXPECT_EQ(0, memcmp(&raw_context, &frame->context, sizeof(raw_context))); +} + +// The stackwalker should be able to produce the context frame even +// without stack memory present. +TEST_F(GetContextFrame, NoStackMemory) { + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, NULL, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(1U, frames->size()); + StackFrameARM *frame = static_cast<StackFrameARM *>(frames->at(0)); + // Check that the values from the original raw context made it + // through to the context in the stack frame. + EXPECT_EQ(0, memcmp(&raw_context, &frame->context, sizeof(raw_context))); +} + +class GetCallerFrame: public StackwalkerARMFixture, public Test { }; + +TEST_F(GetCallerFrame, ScanWithoutSymbols) { + // When the stack walker resorts to scanning the stack, + // only addresses located within loaded modules are + // considered valid return addresses. + // Force scanning through three frames to ensure that the + // stack pointer is set properly in scan-recovered frames. + stack_section.start() = 0x80000000; + uint32_t return_address1 = 0x50000100; + uint32_t return_address2 = 0x50000900; + Label frame1_sp, frame2_sp; + stack_section + // frame 0 + .Append(16, 0) // space + + .D32(0x40090000) // junk that's not + .D32(0x60000000) // a return address + + .D32(return_address1) // actual return address + // frame 1 + .Mark(&frame1_sp) + .Append(16, 0) // space + + .D32(0xF0000000) // more junk + .D32(0x0000000D) + + .D32(return_address2) // actual return address + // frame 2 + .Mark(&frame2_sp) + .Append(32, 0); // end of stack + RegionFromSection(); + + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510; + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(2U, modules_without_symbols.size()); + ASSERT_EQ("module1", modules_without_symbols[0]->debug_file()); + ASSERT_EQ("module2", modules_without_symbols[1]->debug_file()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(3U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity); + EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context))); + + StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1)); + EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame1->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_SP), + frame1->context_validity); + EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]); + + StackFrameARM *frame2 = static_cast<StackFrameARM *>(frames->at(2)); + EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame2->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_SP), + frame2->context_validity); + EXPECT_EQ(return_address2, frame2->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(frame2_sp.Value(), frame2->context.iregs[MD_CONTEXT_ARM_REG_SP]); +} + +TEST_F(GetCallerFrame, ScanWithFunctionSymbols) { + // During stack scanning, if a potential return address + // is located within a loaded module that has symbols, + // it is only considered a valid return address if it + // lies within a function's bounds. + stack_section.start() = 0x80000000; + uint32_t return_address = 0x50000200; + Label frame1_sp; + + stack_section + // frame 0 + .Append(16, 0) // space + + .D32(0x40090000) // junk that's not + .D32(0x60000000) // a return address + + .D32(0x40001000) // a couple of plausible addresses + .D32(0x5000F000) // that are not within functions + + .D32(return_address) // actual return address + // frame 1 + .Mark(&frame1_sp) + .Append(32, 0); // end of stack + RegionFromSection(); + + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40000200; + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + SetModuleSymbols(&module1, + // The youngest frame's function. + "FUNC 100 400 10 monotreme\n"); + SetModuleSymbols(&module2, + // The calling frame's function. + "FUNC 100 400 10 marsupial\n"); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(2U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity); + EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context))); + EXPECT_EQ("monotreme", frame0->function_name); + EXPECT_EQ(0x40000100U, frame0->function_base); + + StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1)); + EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame1->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_SP), + frame1->context_validity); + EXPECT_EQ(return_address, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]); + EXPECT_EQ("marsupial", frame1->function_name); + EXPECT_EQ(0x50000100U, frame1->function_base); +} + +TEST_F(GetCallerFrame, ScanFirstFrame) { + // If the stackwalker resorts to stack scanning, it will scan much + // farther to find the caller of the context frame. + stack_section.start() = 0x80000000; + uint32_t return_address1 = 0x50000100; + uint32_t return_address2 = 0x50000900; + Label frame1_sp, frame2_sp; + stack_section + // frame 0 + .Append(32, 0) // space + + .D32(0x40090000) // junk that's not + .D32(0x60000000) // a return address + + .Append(96, 0) // more space + + .D32(return_address1) // actual return address + // frame 1 + .Mark(&frame1_sp) + .Append(32, 0) // space + + .D32(0xF0000000) // more junk + .D32(0x0000000D) + + .Append(136, 0) // more space + + .D32(return_address2) // actual return address + // (won't be found) + // frame 2 + .Mark(&frame2_sp) + .Append(32, 0); // end of stack + RegionFromSection(); + + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510; + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(2U, modules_without_symbols.size()); + ASSERT_EQ("module1", modules_without_symbols[0]->debug_file()); + ASSERT_EQ("module2", modules_without_symbols[1]->debug_file()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(2U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity); + EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context))); + + StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1)); + EXPECT_EQ(StackFrame::FRAME_TRUST_SCAN, frame1->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_SP), + frame1->context_validity); + EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]); +} + +// Test that set_max_frames_scanned prevents using stack scanning +// to find caller frames. +TEST_F(GetCallerFrame, ScanningNotAllowed) { + // When the stack walker resorts to scanning the stack, + // only addresses located within loaded modules are + // considered valid return addresses. + stack_section.start() = 0x80000000; + uint32_t return_address1 = 0x50000100; + uint32_t return_address2 = 0x50000900; + Label frame1_sp, frame2_sp; + stack_section + // frame 0 + .Append(16, 0) // space + + .D32(0x40090000) // junk that's not + .D32(0x60000000) // a return address + + .D32(return_address1) // actual return address + // frame 1 + .Mark(&frame1_sp) + .Append(16, 0) // space + + .D32(0xF0000000) // more junk + .D32(0x0000000D) + + .D32(return_address2) // actual return address + // frame 2 + .Mark(&frame2_sp) + .Append(32, 0); // end of stack + RegionFromSection(); + + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510; + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + Stackwalker::set_max_frames_scanned(0); + + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(1U, modules_without_symbols.size()); + ASSERT_EQ("module1", modules_without_symbols[0]->debug_file()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(1U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity); + EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context))); +} + +struct CFIFixture: public StackwalkerARMFixture { + CFIFixture() { + // Provide a bunch of STACK CFI records; we'll walk to the caller + // from every point in this series, expecting to find the same set + // of register values. + SetModuleSymbols(&module1, + // The youngest frame's function. + "FUNC 4000 1000 10 enchiridion\n" + // Initially, nothing has been pushed on the stack, + // and the return address is still in the link register. + "STACK CFI INIT 4000 100 .cfa: sp .ra: lr\n" + // Push r4, the frame pointer, and the link register. + "STACK CFI 4001 .cfa: sp 12 + r4: .cfa 12 - ^" + " r11: .cfa 8 - ^ .ra: .cfa 4 - ^\n" + // Save r4..r7 in r0..r3: verify that we populate + // the youngest frame with all the values we have. + "STACK CFI 4002 r4: r0 r5: r1 r6: r2 r7: r3\n" + // Restore r4..r7. Save the non-callee-saves register r1. + "STACK CFI 4003 .cfa: sp 16 + r1: .cfa 16 - ^" + " r4: r4 r5: r5 r6: r6 r7: r7\n" + // Move the .cfa back four bytes, to point at the return + // address, and restore the sp explicitly. + "STACK CFI 4005 .cfa: sp 12 + r1: .cfa 12 - ^" + " r11: .cfa 4 - ^ .ra: .cfa ^ sp: .cfa 4 +\n" + // Recover the PC explicitly from a new stack slot; + // provide garbage for the .ra. + "STACK CFI 4006 .cfa: sp 16 + pc: .cfa 16 - ^\n" + + // The calling function. + "FUNC 5000 1000 10 epictetus\n" + // Mark it as end of stack. + "STACK CFI INIT 5000 1000 .cfa: 0 .ra: 0\n" + + // A function whose CFI makes the stack pointer + // go backwards. + "FUNC 6000 1000 20 palinal\n" + "STACK CFI INIT 6000 1000 .cfa: sp 4 - .ra: lr\n" + + // A function with CFI expressions that can't be + // evaluated. + "FUNC 7000 1000 20 rhetorical\n" + "STACK CFI INIT 7000 1000 .cfa: moot .ra: ambiguous\n"); + + // Provide some distinctive values for the caller's registers. + expected.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510; + expected.iregs[MD_CONTEXT_ARM_REG_SP] = 0x80000000; + expected.iregs[4] = 0xb5d55e68; + expected.iregs[5] = 0xebd134f3; + expected.iregs[6] = 0xa31e74bc; + expected.iregs[7] = 0x2dcb16b3; + expected.iregs[8] = 0x2ada2137; + expected.iregs[9] = 0xbbbb557d; + expected.iregs[10] = 0x48bf8ca7; + expected.iregs[MD_CONTEXT_ARM_REG_FP] = 0x8112e110; + + // Expect CFI to recover all callee-saves registers. Since CFI is the + // only stack frame construction technique we have, aside from the + // context frame itself, there's no way for us to have a set of valid + // registers smaller than this. + expected_validity = (StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_SP | + StackFrameARM::CONTEXT_VALID_R4 | + StackFrameARM::CONTEXT_VALID_R5 | + StackFrameARM::CONTEXT_VALID_R6 | + StackFrameARM::CONTEXT_VALID_R7 | + StackFrameARM::CONTEXT_VALID_R8 | + StackFrameARM::CONTEXT_VALID_R9 | + StackFrameARM::CONTEXT_VALID_R10 | + StackFrameARM::CONTEXT_VALID_FP); + + // By default, context frames provide all registers, as normal. + context_frame_validity = StackFrameARM::CONTEXT_VALID_ALL; + + // By default, registers are unchanged. + raw_context = expected; + } + + // Walk the stack, using stack_section as the contents of the stack + // and raw_context as the current register values. (Set the stack + // pointer to the stack's starting address.) Expect two stack + // frames; in the older frame, expect the callee-saves registers to + // have values matching those in 'expected'. + void CheckWalk() { + RegionFromSection(); + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, + &modules, &frame_symbolizer); + walker.SetContextFrameValidity(context_frame_validity); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(2U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(context_frame_validity, frame0->context_validity); + EXPECT_EQ("enchiridion", frame0->function_name); + EXPECT_EQ(0x40004000U, frame0->function_base); + + StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CFI, frame1->trust); + ASSERT_EQ(expected_validity, frame1->context_validity); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R1) + EXPECT_EQ(expected.iregs[1], frame1->context.iregs[1]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R4) + EXPECT_EQ(expected.iregs[4], frame1->context.iregs[4]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R5) + EXPECT_EQ(expected.iregs[5], frame1->context.iregs[5]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R6) + EXPECT_EQ(expected.iregs[6], frame1->context.iregs[6]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R7) + EXPECT_EQ(expected.iregs[7], frame1->context.iregs[7]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R8) + EXPECT_EQ(expected.iregs[8], frame1->context.iregs[8]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R9) + EXPECT_EQ(expected.iregs[9], frame1->context.iregs[9]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_R10) + EXPECT_EQ(expected.iregs[10], frame1->context.iregs[10]); + if (expected_validity & StackFrameARM::CONTEXT_VALID_FP) + EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_FP], + frame1->context.iregs[MD_CONTEXT_ARM_REG_FP]); + + // We would never have gotten a frame in the first place if the SP + // and PC weren't valid or ->instruction weren't set. + EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_SP], + frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]); + EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_PC], + frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(expected.iregs[MD_CONTEXT_ARM_REG_PC], + frame1->instruction + 2); + EXPECT_EQ("epictetus", frame1->function_name); + } + + // The values we expect to find for the caller's registers. + MDRawContextARM expected; + + // The validity mask for expected. + int expected_validity; + + // The validity mask to impose on the context frame. + int context_frame_validity; +}; + +class CFI: public CFIFixture, public Test { }; + +TEST_F(CFI, At4000) { + stack_section.start() = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004000; + raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = 0x40005510; + CheckWalk(); +} + +TEST_F(CFI, At4001) { + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0xb5d55e68) // saved r4 + .D32(0x8112e110) // saved fp + .D32(0x40005510) // return address + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004001; + raw_context.iregs[4] = 0x635adc9f; // distinct callee r4 + raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0xbe145fc4; // distinct callee fp + CheckWalk(); +} + +// As above, but unwind from a context that has only the PC and SP. +TEST_F(CFI, At4001LimitedValidity) { + context_frame_validity = + StackFrameARM::CONTEXT_VALID_PC | StackFrameARM::CONTEXT_VALID_SP; + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004001; + raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0xbe145fc4; // distinct callee fp + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0xb5d55e68) // saved r4 + .D32(0x8112e110) // saved fp + .D32(0x40005510) // return address + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + expected_validity = (StackFrameARM::CONTEXT_VALID_PC + | StackFrameARM::CONTEXT_VALID_SP + | StackFrameARM::CONTEXT_VALID_FP + | StackFrameARM::CONTEXT_VALID_R4); + CheckWalk(); +} + +TEST_F(CFI, At4002) { + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0xfb81ff3d) // no longer saved r4 + .D32(0x8112e110) // saved fp + .D32(0x40005510) // return address + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004002; + raw_context.iregs[0] = 0xb5d55e68; // saved r4 + raw_context.iregs[1] = 0xebd134f3; // saved r5 + raw_context.iregs[2] = 0xa31e74bc; // saved r6 + raw_context.iregs[3] = 0x2dcb16b3; // saved r7 + raw_context.iregs[4] = 0xfdd35466; // distinct callee r4 + raw_context.iregs[5] = 0xf18c946c; // distinct callee r5 + raw_context.iregs[6] = 0xac2079e8; // distinct callee r6 + raw_context.iregs[7] = 0xa449829f; // distinct callee r7 + raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0xbe145fc4; // distinct callee fp + CheckWalk(); +} + +TEST_F(CFI, At4003) { + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves) + .D32(0xcb78040e) // no longer saved r4 + .D32(0x8112e110) // saved fp + .D32(0x40005510) // return address + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004003; + raw_context.iregs[1] = 0xfb756319; // distinct callee r1 + raw_context.iregs[MD_CONTEXT_ARM_REG_FP] = 0x0a2857ea; // distinct callee fp + expected.iregs[1] = 0x48c8dd5a; // caller's r1 + expected_validity |= StackFrameARM::CONTEXT_VALID_R1; + CheckWalk(); +} + +// We have no new rule at module offset 0x4004, so the results here should +// be the same as those at module offset 0x4003. +TEST_F(CFI, At4004) { + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves) + .D32(0xcb78040e) // no longer saved r4 + .D32(0x8112e110) // saved fp + .D32(0x40005510) // return address + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004004; + raw_context.iregs[1] = 0xfb756319; // distinct callee r1 + expected.iregs[1] = 0x48c8dd5a; // caller's r1 + expected_validity |= StackFrameARM::CONTEXT_VALID_R1; + CheckWalk(); +} + +// Here we move the .cfa, but provide an explicit rule to recover the SP, +// so again there should be no change in the registers recovered. +TEST_F(CFI, At4005) { + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves) + .D32(0xf013f841) // no longer saved r4 + .D32(0x8112e110) // saved fp + .D32(0x40005510) // return address + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004005; + raw_context.iregs[1] = 0xfb756319; // distinct callee r1 + expected.iregs[1] = 0x48c8dd5a; // caller's r1 + expected_validity |= StackFrameARM::CONTEXT_VALID_R1; + CheckWalk(); +} + +// Here we provide an explicit rule for the PC, and have the saved .ra be +// bogus. +TEST_F(CFI, At4006) { + Label frame1_sp = expected.iregs[MD_CONTEXT_ARM_REG_SP]; + stack_section + .D32(0x40005510) // saved pc + .D32(0x48c8dd5a) // saved r1 (even though it's not callee-saves) + .D32(0xf013f841) // no longer saved r4 + .D32(0x8112e110) // saved fp + .D32(0xf8d15783) // .ra rule recovers this, which is garbage + .Mark(&frame1_sp); // This effectively sets stack_section.start(). + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40004006; + raw_context.iregs[1] = 0xfb756319; // callee's r1, different from caller's + expected.iregs[1] = 0x48c8dd5a; // caller's r1 + expected_validity |= StackFrameARM::CONTEXT_VALID_R1; + CheckWalk(); +} + +// Check that we reject rules that would cause the stack pointer to +// move in the wrong direction. +TEST_F(CFI, RejectBackwards) { + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40006000; + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = 0x80000000; + raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = 0x40005510; + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(1U, frames->size()); +} + +// Check that we reject rules whose expressions' evaluation fails. +TEST_F(CFI, RejectBadExpressions) { + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40007000; + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = 0x80000000; + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, -1, &stack_region, &modules, + &frame_symbolizer); + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(0U, modules_without_symbols.size()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(1U, frames->size()); +} + +class StackwalkerARMFixtureIOS : public StackwalkerARMFixture { + public: + StackwalkerARMFixtureIOS() { + // iOS_test is used instead of iOS because the stackwalker has a check to + // avoid using CFI for iOS dumps. This is a workaround for bad CFI being + // produced by dump_syms for iOS. + // https://bugs.chromium.org/p/google-breakpad/issues/detail?id=764 + system_info.os = "iOS_test"; + system_info.os_short = "ios_test"; + } +}; + +class GetFramesByFramePointer: public StackwalkerARMFixtureIOS, public Test { }; + +TEST_F(GetFramesByFramePointer, OnlyFramePointer) { + stack_section.start() = 0x80000000; + uint32_t return_address1 = 0x50000100; + uint32_t return_address2 = 0x50000900; + Label frame1_sp, frame2_sp; + Label frame1_fp, frame2_fp; + stack_section + // frame 0 + .Append(32, 0) // Whatever values on the stack. + .D32(0x0000000D) // junk that's not + .D32(0xF0000000) // a return address. + + .Mark(&frame1_fp) // Next fp will point to the next value. + .D32(frame2_fp) // Save current frame pointer. + .D32(return_address2) // Save current link register. + .Mark(&frame1_sp) + + // frame 1 + .Append(32, 0) // Whatever values on the stack. + .D32(0x0000000D) // junk that's not + .D32(0xF0000000) // a return address. + + .Mark(&frame2_fp) + .D32(0) + .D32(0) + .Mark(&frame2_sp) + + // frame 2 + .Append(32, 0) // Whatever values on the stack. + .D32(0x0000000D) // junk that's not + .D32(0xF0000000); // a return address. + RegionFromSection(); + + + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x40005510; + raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = return_address1; + raw_context.iregs[MD_CONTEXT_ARM_REG_IOS_FP] = frame1_fp.Value(); + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, MD_CONTEXT_ARM_REG_IOS_FP, + &stack_region, &modules, &frame_symbolizer); + + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(2U, modules_without_symbols.size()); + ASSERT_EQ("module1", modules_without_symbols[0]->debug_file()); + ASSERT_EQ("module2", modules_without_symbols[1]->debug_file()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(3U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity); + EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context))); + + StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1)); + EXPECT_EQ(StackFrame::FRAME_TRUST_FP, frame1->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_LR | + StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) | + StackFrameARM::CONTEXT_VALID_SP), + frame1->context_validity); + EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(return_address2, frame1->context.iregs[MD_CONTEXT_ARM_REG_LR]); + EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]); + EXPECT_EQ(frame2_fp.Value(), + frame1->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]); + + StackFrameARM *frame2 = static_cast<StackFrameARM *>(frames->at(2)); + EXPECT_EQ(StackFrame::FRAME_TRUST_FP, frame2->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_LR | + StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) | + StackFrameARM::CONTEXT_VALID_SP), + frame2->context_validity); + EXPECT_EQ(return_address2, frame2->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_LR]); + EXPECT_EQ(frame2_sp.Value(), frame2->context.iregs[MD_CONTEXT_ARM_REG_SP]); + EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]); +} + +TEST_F(GetFramesByFramePointer, FramePointerAndCFI) { + // Provide the standatd STACK CFI records that is obtained when exmining an + // executable produced by XCode. + SetModuleSymbols(&module1, + // Adding a function in CFI. + "FUNC 4000 1000 10 enchiridion\n" + + "STACK CFI INIT 4000 100 .cfa: sp 0 + .ra: lr\n" + "STACK CFI 4001 .cfa: sp 8 + .ra: .cfa -4 + ^" + " r7: .cfa -8 + ^\n" + "STACK CFI 4002 .cfa: r7 8 +\n" + ); + + stack_section.start() = 0x80000000; + uint32_t return_address1 = 0x40004010; + uint32_t return_address2 = 0x50000900; + Label frame1_sp, frame2_sp; + Label frame1_fp, frame2_fp; + stack_section + // frame 0 + .Append(32, 0) // Whatever values on the stack. + .D32(0x0000000D) // junk that's not + .D32(0xF0000000) // a return address. + + .Mark(&frame1_fp) // Next fp will point to the next value. + .D32(frame2_fp) // Save current frame pointer. + .D32(return_address2) // Save current link register. + .Mark(&frame1_sp) + + // frame 1 + .Append(32, 0) // Whatever values on the stack. + .D32(0x0000000D) // junk that's not + .D32(0xF0000000) // a return address. + + .Mark(&frame2_fp) + .D32(0) + .D32(0) + .Mark(&frame2_sp) + + // frame 2 + .Append(32, 0) // Whatever values on the stack. + .D32(0x0000000D) // junk that's not + .D32(0xF0000000); // a return address. + RegionFromSection(); + + + raw_context.iregs[MD_CONTEXT_ARM_REG_PC] = 0x50000400; + raw_context.iregs[MD_CONTEXT_ARM_REG_LR] = return_address1; + raw_context.iregs[MD_CONTEXT_ARM_REG_IOS_FP] = frame1_fp.Value(); + raw_context.iregs[MD_CONTEXT_ARM_REG_SP] = stack_section.start().Value(); + + StackFrameSymbolizer frame_symbolizer(&supplier, &resolver); + StackwalkerARM walker(&system_info, &raw_context, MD_CONTEXT_ARM_REG_IOS_FP, + &stack_region, &modules, &frame_symbolizer); + + vector<const CodeModule*> modules_without_symbols; + vector<const CodeModule*> modules_with_corrupt_symbols; + ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols, + &modules_with_corrupt_symbols)); + ASSERT_EQ(1U, modules_without_symbols.size()); + ASSERT_EQ("module2", modules_without_symbols[0]->debug_file()); + ASSERT_EQ(0U, modules_with_corrupt_symbols.size()); + frames = call_stack.frames(); + ASSERT_EQ(3U, frames->size()); + + StackFrameARM *frame0 = static_cast<StackFrameARM *>(frames->at(0)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CONTEXT, frame0->trust); + ASSERT_EQ(StackFrameARM::CONTEXT_VALID_ALL, frame0->context_validity); + EXPECT_EQ(0, memcmp(&raw_context, &frame0->context, sizeof(raw_context))); + + StackFrameARM *frame1 = static_cast<StackFrameARM *>(frames->at(1)); + EXPECT_EQ(StackFrame::FRAME_TRUST_FP, frame1->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_LR | + StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) | + StackFrameARM::CONTEXT_VALID_SP), + frame1->context_validity); + EXPECT_EQ(return_address1, frame1->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(return_address2, frame1->context.iregs[MD_CONTEXT_ARM_REG_LR]); + EXPECT_EQ(frame1_sp.Value(), frame1->context.iregs[MD_CONTEXT_ARM_REG_SP]); + EXPECT_EQ(frame2_fp.Value(), + frame1->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]); + EXPECT_EQ("enchiridion", frame1->function_name); + EXPECT_EQ(0x40004000U, frame1->function_base); + + + StackFrameARM *frame2 = static_cast<StackFrameARM *>(frames->at(2)); + EXPECT_EQ(StackFrame::FRAME_TRUST_CFI, frame2->trust); + ASSERT_EQ((StackFrameARM::CONTEXT_VALID_PC | + StackFrameARM::CONTEXT_VALID_LR | + StackFrameARM::RegisterValidFlag(MD_CONTEXT_ARM_REG_IOS_FP) | + StackFrameARM::CONTEXT_VALID_SP), + frame2->context_validity); + EXPECT_EQ(return_address2, frame2->context.iregs[MD_CONTEXT_ARM_REG_PC]); + EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_LR]); + EXPECT_EQ(frame2_sp.Value(), frame2->context.iregs[MD_CONTEXT_ARM_REG_SP]); + EXPECT_EQ(0U, frame2->context.iregs[MD_CONTEXT_ARM_REG_IOS_FP]); +} |