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| -rw-r--r-- | memory/gtest/TestJemalloc.cpp | 756 |
1 files changed, 756 insertions, 0 deletions
diff --git a/memory/gtest/TestJemalloc.cpp b/memory/gtest/TestJemalloc.cpp new file mode 100644 index 0000000000..7f3b3f9cf3 --- /dev/null +++ b/memory/gtest/TestJemalloc.cpp @@ -0,0 +1,756 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* 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/. */ + +#include "mozilla/mozalloc.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Unused.h" +#include "mozilla/Vector.h" +#include "mozilla/gtest/MozHelpers.h" +#include "mozmemory.h" +#include "nsCOMPtr.h" +#include "Utils.h" + +#include "gtest/gtest.h" + +#ifdef MOZ_PHC +# include "replace_malloc_bridge.h" +#endif + +using namespace mozilla; + +class AutoDisablePHCOnCurrentThread { + public: + AutoDisablePHCOnCurrentThread() { +#ifdef MOZ_PHC + ReplaceMalloc::DisablePHCOnCurrentThread(); +#endif + } + + ~AutoDisablePHCOnCurrentThread() { +#ifdef MOZ_PHC + ReplaceMalloc::ReenablePHCOnCurrentThread(); +#endif + } +}; + +static inline void TestOne(size_t size) { + size_t req = size; + size_t adv = malloc_good_size(req); + char* p = (char*)malloc(req); + size_t usable = moz_malloc_usable_size(p); + // NB: Using EXPECT here so that we still free the memory on failure. + EXPECT_EQ(adv, usable) << "malloc_good_size(" << req << ") --> " << adv + << "; " + "malloc_usable_size(" + << req << ") --> " << usable; + free(p); +} + +static inline void TestThree(size_t size) { + ASSERT_NO_FATAL_FAILURE(TestOne(size - 1)); + ASSERT_NO_FATAL_FAILURE(TestOne(size)); + ASSERT_NO_FATAL_FAILURE(TestOne(size + 1)); +} + +TEST(Jemalloc, UsableSizeInAdvance) +{ + /* + * Test every size up to a certain point, then (N-1, N, N+1) triplets for a + * various sizes beyond that. + */ + + for (size_t n = 0; n < 16_KiB; n++) ASSERT_NO_FATAL_FAILURE(TestOne(n)); + + for (size_t n = 16_KiB; n < 1_MiB; n += 4_KiB) + ASSERT_NO_FATAL_FAILURE(TestThree(n)); + + for (size_t n = 1_MiB; n < 8_MiB; n += 128_KiB) + ASSERT_NO_FATAL_FAILURE(TestThree(n)); +} + +static int gStaticVar; + +bool InfoEq(jemalloc_ptr_info_t& aInfo, PtrInfoTag aTag, void* aAddr, + size_t aSize, arena_id_t arenaId) { + return aInfo.tag == aTag && aInfo.addr == aAddr && aInfo.size == aSize +#ifdef MOZ_DEBUG + && aInfo.arenaId == arenaId +#endif + ; +} + +bool InfoEqFreedPage(jemalloc_ptr_info_t& aInfo, void* aAddr, size_t aPageSize, + arena_id_t arenaId) { + size_t pageSizeMask = aPageSize - 1; + + return jemalloc_ptr_is_freed_page(&aInfo) && + aInfo.addr == (void*)(uintptr_t(aAddr) & ~pageSizeMask) && + aInfo.size == aPageSize +#ifdef MOZ_DEBUG + && aInfo.arenaId == arenaId +#endif + ; +} + +TEST(Jemalloc, PtrInfo) +{ + arena_id_t arenaId = moz_create_arena(); + ASSERT_TRUE(arenaId != 0); + + jemalloc_stats_t stats; + jemalloc_stats(&stats); + + jemalloc_ptr_info_t info; + Vector<char*> small, large, huge; + + // For small (less than half the page size) allocations, test every position + // within many possible sizes. + size_t small_max = + stats.subpage_max ? stats.subpage_max : stats.quantum_wide_max; + for (size_t n = 0; n <= small_max; n += 8) { + auto p = (char*)moz_arena_malloc(arenaId, n); + size_t usable = moz_malloc_size_of(p); + ASSERT_TRUE(small.append(p)); + for (size_t j = 0; j < usable; j++) { + jemalloc_ptr_info(&p[j], &info); + ASSERT_TRUE(InfoEq(info, TagLiveAlloc, p, usable, arenaId)); + } + } + + // Similar for large (small_max + 1 KiB .. 1MiB - 8KiB) allocations. + for (size_t n = small_max + 1_KiB; n <= stats.large_max; n += 1_KiB) { + auto p = (char*)moz_arena_malloc(arenaId, n); + size_t usable = moz_malloc_size_of(p); + ASSERT_TRUE(large.append(p)); + for (size_t j = 0; j < usable; j += 347) { + jemalloc_ptr_info(&p[j], &info); + ASSERT_TRUE(InfoEq(info, TagLiveAlloc, p, usable, arenaId)); + } + } + + // Similar for huge (> 1MiB - 8KiB) allocations. + for (size_t n = stats.chunksize; n <= 10_MiB; n += 512_KiB) { + auto p = (char*)moz_arena_malloc(arenaId, n); + size_t usable = moz_malloc_size_of(p); + ASSERT_TRUE(huge.append(p)); + for (size_t j = 0; j < usable; j += 567) { + jemalloc_ptr_info(&p[j], &info); + ASSERT_TRUE(InfoEq(info, TagLiveAlloc, p, usable, arenaId)); + } + } + + // The following loops check freed allocations. We step through the vectors + // using prime-sized steps, which gives full coverage of the arrays while + // avoiding deallocating in the same order we allocated. + size_t len; + + // Free the small allocations and recheck them. + int isFreedAlloc = 0, isFreedPage = 0; + len = small.length(); + for (size_t i = 0, j = 0; i < len; i++, j = (j + 19) % len) { + char* p = small[j]; + size_t usable = moz_malloc_size_of(p); + free(p); + for (size_t k = 0; k < usable; k++) { + jemalloc_ptr_info(&p[k], &info); + // There are two valid outcomes here. + if (InfoEq(info, TagFreedAlloc, p, usable, arenaId)) { + isFreedAlloc++; + } else if (InfoEqFreedPage(info, &p[k], stats.page_size, arenaId)) { + isFreedPage++; + } else { + ASSERT_TRUE(false); + } + } + } + // There should be both FreedAlloc and FreedPage results, but a lot more of + // the former. + ASSERT_TRUE(isFreedAlloc != 0); + ASSERT_TRUE(isFreedPage != 0); + ASSERT_TRUE(isFreedAlloc / isFreedPage > 8); + + // Free the large allocations and recheck them. + len = large.length(); + for (size_t i = 0, j = 0; i < len; i++, j = (j + 31) % len) { + char* p = large[j]; + size_t usable = moz_malloc_size_of(p); + free(p); + for (size_t k = 0; k < usable; k += 357) { + jemalloc_ptr_info(&p[k], &info); + ASSERT_TRUE(InfoEqFreedPage(info, &p[k], stats.page_size, arenaId)); + } + } + + // Free the huge allocations and recheck them. + len = huge.length(); + for (size_t i = 0, j = 0; i < len; i++, j = (j + 7) % len) { + char* p = huge[j]; + size_t usable = moz_malloc_size_of(p); + free(p); + for (size_t k = 0; k < usable; k += 587) { + jemalloc_ptr_info(&p[k], &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + } + } + + // Null ptr. + jemalloc_ptr_info(nullptr, &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + + // Near-null ptr. + jemalloc_ptr_info((void*)0x123, &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + + // Maximum address. + jemalloc_ptr_info((void*)uintptr_t(-1), &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + + // Stack memory. + int stackVar; + jemalloc_ptr_info(&stackVar, &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + + // Code memory. + jemalloc_ptr_info((const void*)&jemalloc_ptr_info, &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + + // Static memory. + jemalloc_ptr_info(&gStaticVar, &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + + // Chunk header. + UniquePtr<int> p = MakeUnique<int>(); + size_t chunksizeMask = stats.chunksize - 1; + char* chunk = (char*)(uintptr_t(p.get()) & ~chunksizeMask); + size_t chunkHeaderSize = stats.chunksize - stats.large_max - stats.page_size; + for (size_t i = 0; i < chunkHeaderSize; i += 64) { + jemalloc_ptr_info(&chunk[i], &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + } + + // Run header. + size_t page_sizeMask = stats.page_size - 1; + char* run = (char*)(uintptr_t(p.get()) & ~page_sizeMask); + for (size_t i = 0; i < 4 * sizeof(void*); i++) { + jemalloc_ptr_info(&run[i], &info); + ASSERT_TRUE(InfoEq(info, TagUnknown, nullptr, 0U, 0U)); + } + + // Entire chunk. It's impossible to check what is put into |info| for all of + // these addresses; this is more about checking that we don't crash. + for (size_t i = 0; i < stats.chunksize; i += 256) { + jemalloc_ptr_info(&chunk[i], &info); + } + + moz_dispose_arena(arenaId); +} + +size_t sSizes[] = {1, 42, 79, 918, 1.4_KiB, + 73_KiB, 129_KiB, 1.1_MiB, 2.6_MiB, 5.1_MiB}; + +TEST(Jemalloc, Arenas) +{ + arena_id_t arena = moz_create_arena(); + ASSERT_TRUE(arena != 0); + void* ptr = moz_arena_malloc(arena, 42); + ASSERT_TRUE(ptr != nullptr); + ptr = moz_arena_realloc(arena, ptr, 64); + ASSERT_TRUE(ptr != nullptr); + moz_arena_free(arena, ptr); + ptr = moz_arena_calloc(arena, 24, 2); + // For convenience, free can be used to free arena pointers. + free(ptr); + moz_dispose_arena(arena); + + // Avoid death tests adding some unnecessary (long) delays. + SAVE_GDB_SLEEP_LOCAL(); + + // Can't use an arena after it's disposed. + // ASSERT_DEATH_WRAP(moz_arena_malloc(arena, 80), ""); + + // Arena id 0 can't be used to somehow get to the main arena. + ASSERT_DEATH_WRAP(moz_arena_malloc(0, 80), ""); + + arena = moz_create_arena(); + arena_id_t arena2 = moz_create_arena(); + // Ensure arena2 is used to prevent OSX errors: + (void)arena2; + + // For convenience, realloc can also be used to reallocate arena pointers. + // The result should be in the same arena. Test various size class + // transitions. + for (size_t from_size : sSizes) { + SCOPED_TRACE(testing::Message() << "from_size = " << from_size); + for (size_t to_size : sSizes) { + SCOPED_TRACE(testing::Message() << "to_size = " << to_size); + ptr = moz_arena_malloc(arena, from_size); + ptr = realloc(ptr, to_size); + // Freeing with the wrong arena should crash. + ASSERT_DEATH_WRAP(moz_arena_free(arena2, ptr), ""); + // Likewise for moz_arena_realloc. + ASSERT_DEATH_WRAP(moz_arena_realloc(arena2, ptr, from_size), ""); + // The following will crash if it's not in the right arena. + moz_arena_free(arena, ptr); + } + } + + moz_dispose_arena(arena2); + moz_dispose_arena(arena); + + RESTORE_GDB_SLEEP_LOCAL(); +} + +// Check that a buffer aPtr is entirely filled with a given character from +// aOffset to aSize. For faster comparison, the caller is required to fill a +// reference buffer with the wanted character, and give the size of that +// reference buffer. +static void bulk_compare(char* aPtr, size_t aOffset, size_t aSize, + char* aReference, size_t aReferenceSize) { + for (size_t i = aOffset; i < aSize; i += aReferenceSize) { + size_t length = std::min(aSize - i, aReferenceSize); + if (memcmp(aPtr + i, aReference, length)) { + // We got a mismatch, we now want to report more precisely where. + for (size_t j = i; j < i + length; j++) { + ASSERT_EQ(aPtr[j], *aReference); + } + } + } +} + +// A range iterator for size classes between two given values. +class SizeClassesBetween { + public: + SizeClassesBetween(size_t aStart, size_t aEnd) : mStart(aStart), mEnd(aEnd) {} + + class Iterator { + public: + explicit Iterator(size_t aValue) : mValue(malloc_good_size(aValue)) {} + + operator size_t() const { return mValue; } + size_t operator*() const { return mValue; } + Iterator& operator++() { + mValue = malloc_good_size(mValue + 1); + return *this; + } + + private: + size_t mValue; + }; + + Iterator begin() { return Iterator(mStart); } + Iterator end() { return Iterator(mEnd); } + + private: + size_t mStart, mEnd; +}; + +#define ALIGNMENT_CEILING(s, alignment) \ + (((s) + ((alignment)-1)) & (~((alignment)-1))) + +#define ALIGNMENT_FLOOR(s, alignment) ((s) & (~((alignment)-1))) + +static bool IsSameRoundedHugeClass(size_t aSize1, size_t aSize2, + jemalloc_stats_t& aStats) { + return (aSize1 > aStats.large_max && aSize2 > aStats.large_max && + ALIGNMENT_CEILING(aSize1 + aStats.page_size, aStats.chunksize) == + ALIGNMENT_CEILING(aSize2 + aStats.page_size, aStats.chunksize)); +} + +static bool CanReallocInPlace(size_t aFromSize, size_t aToSize, + jemalloc_stats_t& aStats) { + // PHC allocations must be disabled because PHC reallocs differently to + // mozjemalloc. +#ifdef MOZ_PHC + MOZ_RELEASE_ASSERT(!ReplaceMalloc::IsPHCEnabledOnCurrentThread()); +#endif + + if (aFromSize == malloc_good_size(aToSize)) { + // Same size class: in-place. + return true; + } + if (aFromSize >= aStats.page_size && aFromSize <= aStats.large_max && + aToSize >= aStats.page_size && aToSize <= aStats.large_max) { + // Any large class to any large class: in-place when there is space to. + return true; + } + if (IsSameRoundedHugeClass(aFromSize, aToSize, aStats)) { + // Huge sizes that round up to the same multiple of the chunk size: + // in-place. + return true; + } + return false; +} + +TEST(Jemalloc, InPlace) +{ + // Disable PHC allocations for this test, because CanReallocInPlace() isn't + // valid for PHC allocations. + AutoDisablePHCOnCurrentThread disable; + + jemalloc_stats_t stats; + jemalloc_stats(&stats); + + // Using a separate arena, which is always emptied after an iteration, ensures + // that in-place reallocation happens in all cases it can happen. This test is + // intended for developers to notice they may have to adapt other tests if + // they change the conditions for in-place reallocation. + arena_id_t arena = moz_create_arena(); + + for (size_t from_size : SizeClassesBetween(1, 2 * stats.chunksize)) { + SCOPED_TRACE(testing::Message() << "from_size = " << from_size); + for (size_t to_size : sSizes) { + SCOPED_TRACE(testing::Message() << "to_size = " << to_size); + char* ptr = (char*)moz_arena_malloc(arena, from_size); + char* ptr2 = (char*)moz_arena_realloc(arena, ptr, to_size); + if (CanReallocInPlace(from_size, to_size, stats)) { + EXPECT_EQ(ptr, ptr2); + } else { + EXPECT_NE(ptr, ptr2); + } + moz_arena_free(arena, ptr2); + } + } + + moz_dispose_arena(arena); +} + +// Bug 1474254: disable this test for windows ccov builds because it leads to +// timeout. +#if !defined(XP_WIN) || !defined(MOZ_CODE_COVERAGE) +TEST(Jemalloc, JunkPoison) +{ + // Disable PHC allocations for this test, because CanReallocInPlace() isn't + // valid for PHC allocations, and the testing UAFs aren't valid. + AutoDisablePHCOnCurrentThread disable; + + jemalloc_stats_t stats; + jemalloc_stats(&stats); + + // Avoid death tests adding some unnecessary (long) delays. + SAVE_GDB_SLEEP_LOCAL(); + + // Create buffers in a separate arena, for faster comparisons with + // bulk_compare. + arena_id_t buf_arena = moz_create_arena(); + char* junk_buf = (char*)moz_arena_malloc(buf_arena, stats.page_size); + // Depending on its configuration, the allocator will either fill the + // requested allocation with the junk byte (0xe4) or with zeroes, or do + // nothing, in which case, since we're allocating in a fresh arena, + // we'll be getting zeroes. + char junk = stats.opt_junk ? '\xe4' : '\0'; + for (size_t i = 0; i < stats.page_size; i++) { + ASSERT_EQ(junk_buf[i], junk); + } + + char* poison_buf = (char*)moz_arena_malloc(buf_arena, stats.page_size); + memset(poison_buf, 0xe5, stats.page_size); + + static const char fill = 0x42; + char* fill_buf = (char*)moz_arena_malloc(buf_arena, stats.page_size); + memset(fill_buf, fill, stats.page_size); + + arena_params_t params; + // Allow as many dirty pages in the arena as possible, so that purge never + // happens in it. Purge breaks some of the tests below randomly depending on + // what other things happen on other threads. + params.mMaxDirty = size_t(-1); + arena_id_t arena = moz_create_arena_with_params(¶ms); + + // Allocating should junk the buffer, and freeing should poison the buffer. + for (size_t size : sSizes) { + if (size <= stats.large_max) { + SCOPED_TRACE(testing::Message() << "size = " << size); + char* buf = (char*)moz_arena_malloc(arena, size); + size_t allocated = moz_malloc_usable_size(buf); + if (stats.opt_junk || stats.opt_zero) { + ASSERT_NO_FATAL_FAILURE( + bulk_compare(buf, 0, allocated, junk_buf, stats.page_size)); + } + moz_arena_free(arena, buf); + // We purposefully do a use-after-free here, to check that the data was + // poisoned. + ASSERT_NO_FATAL_FAILURE( + bulk_compare(buf, 0, allocated, poison_buf, stats.page_size)); + } + } + + // Shrinking in the same size class should be in place and poison between the + // new allocation size and the old one. + size_t prev = 0; + for (size_t size : SizeClassesBetween(1, 2 * stats.chunksize)) { + SCOPED_TRACE(testing::Message() << "size = " << size); + SCOPED_TRACE(testing::Message() << "prev = " << prev); + char* ptr = (char*)moz_arena_malloc(arena, size); + memset(ptr, fill, moz_malloc_usable_size(ptr)); + char* ptr2 = (char*)moz_arena_realloc(arena, ptr, prev + 1); + ASSERT_EQ(ptr, ptr2); + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr, 0, prev + 1, fill_buf, stats.page_size)); + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr, prev + 1, size, poison_buf, stats.page_size)); + moz_arena_free(arena, ptr); + prev = size; + } + + // In-place realloc should junk the new bytes when growing and poison the old + // bytes when shrinking. + for (size_t from_size : SizeClassesBetween(1, 2 * stats.chunksize)) { + SCOPED_TRACE(testing::Message() << "from_size = " << from_size); + for (size_t to_size : sSizes) { + SCOPED_TRACE(testing::Message() << "to_size = " << to_size); + if (CanReallocInPlace(from_size, to_size, stats)) { + char* ptr = (char*)moz_arena_malloc(arena, from_size); + memset(ptr, fill, moz_malloc_usable_size(ptr)); + char* ptr2 = (char*)moz_arena_realloc(arena, ptr, to_size); + ASSERT_EQ(ptr, ptr2); + // Shrinking allocation + if (from_size >= to_size) { + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr, 0, to_size, fill_buf, stats.page_size)); + // Huge allocations have guards and will crash when accessing + // beyond the valid range. + if (to_size > stats.large_max) { + size_t page_limit = ALIGNMENT_CEILING(to_size, stats.page_size); + ASSERT_NO_FATAL_FAILURE(bulk_compare(ptr, to_size, page_limit, + poison_buf, stats.page_size)); + ASSERT_DEATH_WRAP(ptr[page_limit] = 0, ""); + } else { + ASSERT_NO_FATAL_FAILURE(bulk_compare(ptr, to_size, from_size, + poison_buf, stats.page_size)); + } + } else { + // Enlarging allocation + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr, 0, from_size, fill_buf, stats.page_size)); + if (stats.opt_junk || stats.opt_zero) { + ASSERT_NO_FATAL_FAILURE(bulk_compare(ptr, from_size, to_size, + junk_buf, stats.page_size)); + } + // Huge allocation, so should have a guard page following + if (to_size > stats.large_max) { + ASSERT_DEATH_WRAP( + ptr[ALIGNMENT_CEILING(to_size, stats.page_size)] = 0, ""); + } + } + moz_arena_free(arena, ptr2); + } + } + } + + // Growing to a different size class should poison the old allocation, + // preserve the original bytes, and junk the new bytes in the new allocation. + for (size_t from_size : SizeClassesBetween(1, 2 * stats.chunksize)) { + SCOPED_TRACE(testing::Message() << "from_size = " << from_size); + for (size_t to_size : sSizes) { + if (from_size < to_size && malloc_good_size(to_size) != from_size && + !IsSameRoundedHugeClass(from_size, to_size, stats)) { + SCOPED_TRACE(testing::Message() << "to_size = " << to_size); + char* ptr = (char*)moz_arena_malloc(arena, from_size); + memset(ptr, fill, moz_malloc_usable_size(ptr)); + // Avoid in-place realloc by allocating a buffer, expecting it to be + // right after the buffer we just received. Buffers smaller than the + // page size and exactly or larger than the size of the largest large + // size class can't be reallocated in-place. + char* avoid_inplace = nullptr; + if (from_size >= stats.page_size && from_size < stats.large_max) { + avoid_inplace = (char*)moz_arena_malloc(arena, stats.page_size); + ASSERT_EQ(ptr + from_size, avoid_inplace); + } + char* ptr2 = (char*)moz_arena_realloc(arena, ptr, to_size); + ASSERT_NE(ptr, ptr2); + if (from_size <= stats.large_max) { + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr, 0, from_size, poison_buf, stats.page_size)); + } + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr2, 0, from_size, fill_buf, stats.page_size)); + if (stats.opt_junk || stats.opt_zero) { + size_t rounded_to_size = malloc_good_size(to_size); + ASSERT_NE(to_size, rounded_to_size); + ASSERT_NO_FATAL_FAILURE(bulk_compare(ptr2, from_size, rounded_to_size, + junk_buf, stats.page_size)); + } + moz_arena_free(arena, ptr2); + moz_arena_free(arena, avoid_inplace); + } + } + } + + // Shrinking to a different size class should poison the old allocation, + // preserve the original bytes, and junk the extra bytes in the new + // allocation. + for (size_t from_size : SizeClassesBetween(1, 2 * stats.chunksize)) { + SCOPED_TRACE(testing::Message() << "from_size = " << from_size); + for (size_t to_size : sSizes) { + if (from_size > to_size && + !CanReallocInPlace(from_size, to_size, stats)) { + SCOPED_TRACE(testing::Message() << "to_size = " << to_size); + char* ptr = (char*)moz_arena_malloc(arena, from_size); + memset(ptr, fill, from_size); + char* ptr2 = (char*)moz_arena_realloc(arena, ptr, to_size); + ASSERT_NE(ptr, ptr2); + if (from_size <= stats.large_max) { + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr, 0, from_size, poison_buf, stats.page_size)); + } + ASSERT_NO_FATAL_FAILURE( + bulk_compare(ptr2, 0, to_size, fill_buf, stats.page_size)); + if (stats.opt_junk || stats.opt_zero) { + size_t rounded_to_size = malloc_good_size(to_size); + ASSERT_NE(to_size, rounded_to_size); + ASSERT_NO_FATAL_FAILURE(bulk_compare(ptr2, from_size, rounded_to_size, + junk_buf, stats.page_size)); + } + moz_arena_free(arena, ptr2); + } + } + } + + moz_dispose_arena(arena); + + moz_arena_free(buf_arena, poison_buf); + moz_arena_free(buf_arena, junk_buf); + moz_arena_free(buf_arena, fill_buf); + moz_dispose_arena(buf_arena); + + RESTORE_GDB_SLEEP_LOCAL(); +} +#endif // !defined(XP_WIN) || !defined(MOZ_CODE_COVERAGE) + +TEST(Jemalloc, TrailingGuard) +{ + // Disable PHC allocations for this test, because even a single PHC + // allocation occurring can throw it off. + AutoDisablePHCOnCurrentThread disable; + + jemalloc_stats_t stats; + jemalloc_stats(&stats); + + // Avoid death tests adding some unnecessary (long) delays. + SAVE_GDB_SLEEP_LOCAL(); + + arena_id_t arena = moz_create_arena(); + ASSERT_TRUE(arena != 0); + + // Do enough large allocations to fill a chunk, and then one additional one, + // and check that the guard page is still present after the one-but-last + // allocation, i.e. that we didn't allocate the guard. + Vector<void*> ptr_list; + for (size_t cnt = 0; cnt < stats.large_max / stats.page_size; cnt++) { + void* ptr = moz_arena_malloc(arena, stats.page_size); + ASSERT_TRUE(ptr != nullptr); + ASSERT_TRUE(ptr_list.append(ptr)); + } + + void* last_ptr_in_chunk = ptr_list[ptr_list.length() - 1]; + void* extra_ptr = moz_arena_malloc(arena, stats.page_size); + void* guard_page = (void*)ALIGNMENT_CEILING( + (uintptr_t)last_ptr_in_chunk + stats.page_size, stats.page_size); + jemalloc_ptr_info_t info; + jemalloc_ptr_info(guard_page, &info); + ASSERT_TRUE(jemalloc_ptr_is_freed_page(&info)); + + ASSERT_DEATH_WRAP(*(char*)guard_page = 0, ""); + + for (void* ptr : ptr_list) { + moz_arena_free(arena, ptr); + } + moz_arena_free(arena, extra_ptr); + + moz_dispose_arena(arena); + + RESTORE_GDB_SLEEP_LOCAL(); +} + +TEST(Jemalloc, LeadingGuard) +{ + // Disable PHC allocations for this test, because even a single PHC + // allocation occurring can throw it off. + AutoDisablePHCOnCurrentThread disable; + + jemalloc_stats_t stats; + jemalloc_stats(&stats); + + // Avoid death tests adding some unnecessary (long) delays. + SAVE_GDB_SLEEP_LOCAL(); + + arena_id_t arena = moz_create_arena(); + ASSERT_TRUE(arena != 0); + + // Do a simple normal allocation, but force all the allocation space + // in the chunk to be used up. This allows us to check that we get + // the safe area right in the logic that follows (all memory will be + // committed and initialized), and it forces this pointer to the start + // of the zone to sit at the very start of the usable chunk area. + void* ptr = moz_arena_malloc(arena, stats.large_max); + ASSERT_TRUE(ptr != nullptr); + // If ptr is chunk-aligned, the above allocation went wrong. + void* chunk_start = (void*)ALIGNMENT_FLOOR((uintptr_t)ptr, stats.chunksize); + ASSERT_NE((uintptr_t)ptr, (uintptr_t)chunk_start); + // If ptr is 1 page after the chunk start (so right after the header), + // we must have missed adding the guard page. + ASSERT_NE((uintptr_t)ptr, (uintptr_t)chunk_start + stats.page_size); + // The actual start depends on the amount of metadata versus the page + // size, so we can't check equality without pulling in too many + // implementation details. + + // Guard page should be right before data area + void* guard_page = (void*)(((uintptr_t)ptr) - sizeof(void*)); + jemalloc_ptr_info_t info; + jemalloc_ptr_info(guard_page, &info); + ASSERT_TRUE(info.tag == TagUnknown); + ASSERT_DEATH_WRAP(*(char*)guard_page = 0, ""); + + moz_arena_free(arena, ptr); + moz_dispose_arena(arena); + + RESTORE_GDB_SLEEP_LOCAL(); +} + +TEST(Jemalloc, DisposeArena) +{ + jemalloc_stats_t stats; + jemalloc_stats(&stats); + + // Avoid death tests adding some unnecessary (long) delays. + SAVE_GDB_SLEEP_LOCAL(); + + arena_id_t arena = moz_create_arena(); + void* ptr = moz_arena_malloc(arena, 42); + // Disposing of the arena when it's not empty is a MOZ_CRASH-worthy error. + ASSERT_DEATH_WRAP(moz_dispose_arena(arena), ""); + moz_arena_free(arena, ptr); + moz_dispose_arena(arena); + + arena = moz_create_arena(); + ptr = moz_arena_malloc(arena, stats.page_size * 2); + // Disposing of the arena when it's not empty is a MOZ_CRASH-worthy error. + ASSERT_DEATH_WRAP(moz_dispose_arena(arena), ""); + moz_arena_free(arena, ptr); + moz_dispose_arena(arena); + + arena = moz_create_arena(); + ptr = moz_arena_malloc(arena, stats.chunksize * 2); +#ifdef MOZ_DEBUG + // On debug builds, we do the expensive check that arenas are empty. + ASSERT_DEATH_WRAP(moz_dispose_arena(arena), ""); + moz_arena_free(arena, ptr); + moz_dispose_arena(arena); +#else + // Currently, the allocator can't trivially check whether the arena is empty + // of huge allocations, so disposing of it works. + moz_dispose_arena(arena); + // But trying to free a pointer that belongs to it will MOZ_CRASH. + ASSERT_DEATH_WRAP(free(ptr), ""); + // Likewise for realloc + ASSERT_DEATH_WRAP(ptr = realloc(ptr, stats.chunksize * 3), ""); +#endif + + // Using the arena after it's been disposed of is MOZ_CRASH-worthy. + ASSERT_DEATH_WRAP(moz_arena_malloc(arena, 42), ""); + + RESTORE_GDB_SLEEP_LOCAL(); +} |