diff options
Diffstat (limited to 'libsanitizer/asan/asan_fake_stack.cc')
| -rw-r--r-- | libsanitizer/asan/asan_fake_stack.cc | 70 |
1 files changed, 49 insertions, 21 deletions
diff --git a/libsanitizer/asan/asan_fake_stack.cc b/libsanitizer/asan/asan_fake_stack.cc index cfe96a0882f..de190d11a16 100644 --- a/libsanitizer/asan/asan_fake_stack.cc +++ b/libsanitizer/asan/asan_fake_stack.cc @@ -9,6 +9,7 @@ // // FakeStack is used to detect use-after-return bugs. //===----------------------------------------------------------------------===// + #include "asan_allocator.h" #include "asan_poisoning.h" #include "asan_thread.h" @@ -20,13 +21,19 @@ static const u64 kMagic2 = (kMagic1 << 8) | kMagic1; static const u64 kMagic4 = (kMagic2 << 16) | kMagic2; static const u64 kMagic8 = (kMagic4 << 32) | kMagic4; +static const u64 kAllocaRedzoneSize = 32UL; +static const u64 kAllocaRedzoneMask = 31UL; + // For small size classes inline PoisonShadow for better performance. ALWAYS_INLINE void SetShadow(uptr ptr, uptr size, uptr class_id, u64 magic) { CHECK_EQ(SHADOW_SCALE, 3); // This code expects SHADOW_SCALE=3. u64 *shadow = reinterpret_cast<u64*>(MemToShadow(ptr)); if (class_id <= 6) { - for (uptr i = 0; i < (1U << class_id); i++) + for (uptr i = 0; i < (1U << class_id); i++) { shadow[i] = magic; + // Make sure this does not become memset. + SanitizerBreakOptimization(nullptr); + } } else { // The size class is too big, it's cheaper to poison only size bytes. PoisonShadow(ptr, size, static_cast<u8>(magic)); @@ -56,7 +63,7 @@ FakeStack *FakeStack::Create(uptr stack_size_log) { void FakeStack::Destroy(int tid) { PoisonAll(0); - if (common_flags()->verbosity >= 2) { + if (Verbosity() >= 2) { InternalScopedString str(kNumberOfSizeClasses * 50); for (uptr class_id = 0; class_id < kNumberOfSizeClasses; class_id++) str.append("%zd: %zd/%zd; ", class_id, hint_position_[class_id], @@ -73,7 +80,9 @@ void FakeStack::PoisonAll(u8 magic) { magic); } +#if !defined(_MSC_VER) || defined(__clang__) ALWAYS_INLINE USED +#endif FakeFrame *FakeStack::Allocate(uptr stack_size_log, uptr class_id, uptr real_stack) { CHECK_LT(class_id, kNumberOfSizeClasses); @@ -99,7 +108,7 @@ FakeFrame *FakeStack::Allocate(uptr stack_size_log, uptr class_id, *SavedFlagPtr(reinterpret_cast<uptr>(res), class_id) = &flags[pos]; return res; } - return 0; // We are out of fake stack. + return nullptr; // We are out of fake stack. } uptr FakeStack::AddrIsInFakeStack(uptr ptr, uptr *frame_beg, uptr *frame_end) { @@ -176,7 +185,7 @@ void SetTLSFakeStack(FakeStack *fs) { } static FakeStack *GetFakeStack() { AsanThread *t = GetCurrentThread(); - if (!t) return 0; + if (!t) return nullptr; return t->fake_stack(); } @@ -184,40 +193,39 @@ static FakeStack *GetFakeStackFast() { if (FakeStack *fs = GetTLSFakeStack()) return fs; if (!__asan_option_detect_stack_use_after_return) - return 0; + return nullptr; return GetFakeStack(); } -ALWAYS_INLINE uptr OnMalloc(uptr class_id, uptr size, uptr real_stack) { +ALWAYS_INLINE uptr OnMalloc(uptr class_id, uptr size) { FakeStack *fs = GetFakeStackFast(); - if (!fs) return real_stack; + if (!fs) return 0; + uptr local_stack; + uptr real_stack = reinterpret_cast<uptr>(&local_stack); FakeFrame *ff = fs->Allocate(fs->stack_size_log(), class_id, real_stack); - if (!ff) - return real_stack; // Out of fake stack, return the real one. + if (!ff) return 0; // Out of fake stack. uptr ptr = reinterpret_cast<uptr>(ff); SetShadow(ptr, size, class_id, 0); return ptr; } -ALWAYS_INLINE void OnFree(uptr ptr, uptr class_id, uptr size, uptr real_stack) { - if (ptr == real_stack) - return; +ALWAYS_INLINE void OnFree(uptr ptr, uptr class_id, uptr size) { FakeStack::Deallocate(ptr, class_id); SetShadow(ptr, size, class_id, kMagic8); } -} // namespace __asan +} // namespace __asan // ---------------------- Interface ---------------- {{{1 using namespace __asan; #define DEFINE_STACK_MALLOC_FREE_WITH_CLASS_ID(class_id) \ extern "C" SANITIZER_INTERFACE_ATTRIBUTE uptr \ - __asan_stack_malloc_##class_id(uptr size, uptr real_stack) { \ - return OnMalloc(class_id, size, real_stack); \ + __asan_stack_malloc_##class_id(uptr size) { \ + return OnMalloc(class_id, size); \ } \ extern "C" SANITIZER_INTERFACE_ATTRIBUTE void __asan_stack_free_##class_id( \ - uptr ptr, uptr size, uptr real_stack) { \ - OnFree(ptr, class_id, size, real_stack); \ + uptr ptr, uptr size) { \ + OnFree(ptr, class_id, size); \ } DEFINE_STACK_MALLOC_FREE_WITH_CLASS_ID(0) @@ -239,15 +247,35 @@ SANITIZER_INTERFACE_ATTRIBUTE void *__asan_addr_is_in_fake_stack(void *fake_stack, void *addr, void **beg, void **end) { FakeStack *fs = reinterpret_cast<FakeStack*>(fake_stack); - if (!fs) return 0; + if (!fs) return nullptr; uptr frame_beg, frame_end; FakeFrame *frame = reinterpret_cast<FakeFrame *>(fs->AddrIsInFakeStack( reinterpret_cast<uptr>(addr), &frame_beg, &frame_end)); - if (!frame) return 0; + if (!frame) return nullptr; if (frame->magic != kCurrentStackFrameMagic) - return 0; + return nullptr; if (beg) *beg = reinterpret_cast<void*>(frame_beg); if (end) *end = reinterpret_cast<void*>(frame_end); return reinterpret_cast<void*>(frame->real_stack); } -} // extern "C" + +SANITIZER_INTERFACE_ATTRIBUTE +void __asan_alloca_poison(uptr addr, uptr size) { + uptr LeftRedzoneAddr = addr - kAllocaRedzoneSize; + uptr PartialRzAddr = addr + size; + uptr RightRzAddr = (PartialRzAddr + kAllocaRedzoneMask) & ~kAllocaRedzoneMask; + uptr PartialRzAligned = PartialRzAddr & ~(SHADOW_GRANULARITY - 1); + FastPoisonShadow(LeftRedzoneAddr, kAllocaRedzoneSize, kAsanAllocaLeftMagic); + FastPoisonShadowPartialRightRedzone( + PartialRzAligned, PartialRzAddr % SHADOW_GRANULARITY, + RightRzAddr - PartialRzAligned, kAsanAllocaRightMagic); + FastPoisonShadow(RightRzAddr, kAllocaRedzoneSize, kAsanAllocaRightMagic); +} + +SANITIZER_INTERFACE_ATTRIBUTE +void __asan_allocas_unpoison(uptr top, uptr bottom) { + if ((!top) || (top > bottom)) return; + REAL(memset)(reinterpret_cast<void*>(MemToShadow(top)), 0, + (bottom - top) / SHADOW_GRANULARITY); +} +} // extern "C" |