diff options
author | Alex Shlyapnikov <alekseys@google.com> | 2017-12-04 18:00:24 +0000 |
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committer | Alex Shlyapnikov <alekseys@google.com> | 2017-12-04 18:00:24 +0000 |
commit | 1ce8e22e8474d244b05bb842ef54e9d5af7188bc (patch) | |
tree | cabc1a5ab34ed91fd5f334b48a5ec4add8aad7b0 /lib/asan/asan_thread.cc | |
parent | 5551897294887d632c71275cf11c5654fd80cda7 (diff) |
[ASan] Enhance libsanitizer support for invalid-pointer-pair.
Following patch adds support of all memory origins in
CheckForInvalidPointerPair function. For small difference of pointers,
it's directly done in shadow memory (the limit was set to 2048B).
Then we search for origin of first pointer and verify that the second
one has the same origin. If so, we verify that it points either to a same
variable (in case of stack memory or a global variable), or to a same
heap segment.
Committing on behanf of marxin and jakubjelinek.
Reviewers: alekseyshl, kcc
Subscribers: llvm-commits
Differential revision: https://reviews.llvm.org/D40600
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@319668 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/asan/asan_thread.cc')
-rw-r--r-- | lib/asan/asan_thread.cc | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/lib/asan/asan_thread.cc b/lib/asan/asan_thread.cc index c41d3ba94..ad81512df 100644 --- a/lib/asan/asan_thread.cc +++ b/lib/asan/asan_thread.cc @@ -317,7 +317,7 @@ bool AsanThread::GetStackFrameAccessByAddr(uptr addr, access->frame_descr = (const char *)((uptr*)bottom)[1]; return true; } - uptr aligned_addr = addr & ~(SANITIZER_WORDSIZE/8 - 1); // align addr. + uptr aligned_addr = RoundDownTo(addr, SANITIZER_WORDSIZE / 8); // align addr. uptr mem_ptr = RoundDownTo(aligned_addr, SHADOW_GRANULARITY); u8 *shadow_ptr = (u8*)MemToShadow(aligned_addr); u8 *shadow_bottom = (u8*)MemToShadow(bottom); @@ -346,6 +346,29 @@ bool AsanThread::GetStackFrameAccessByAddr(uptr addr, return true; } +uptr AsanThread::GetStackVariableShadowStart(uptr addr) { + uptr bottom = 0; + if (AddrIsInStack(addr)) { + bottom = stack_bottom(); + } else if (has_fake_stack()) { + bottom = fake_stack()->AddrIsInFakeStack(addr); + CHECK(bottom); + } else + return 0; + + uptr aligned_addr = RoundDownTo(addr, SANITIZER_WORDSIZE / 8); // align addr. + u8 *shadow_ptr = (u8*)MemToShadow(aligned_addr); + u8 *shadow_bottom = (u8*)MemToShadow(bottom); + + while (shadow_ptr >= shadow_bottom && + (*shadow_ptr != kAsanStackLeftRedzoneMagic && + *shadow_ptr != kAsanStackMidRedzoneMagic && + *shadow_ptr != kAsanStackRightRedzoneMagic)) + shadow_ptr--; + + return (uptr)shadow_ptr + 1; +} + bool AsanThread::AddrIsInStack(uptr addr) { const auto bounds = GetStackBounds(); return addr >= bounds.bottom && addr < bounds.top; |