diff options
| author | Kostya Serebryany <kcc@google.com> | 2013-09-18 14:07:14 +0000 |
|---|---|---|
| committer | Kostya Serebryany <kcc@google.com> | 2013-09-18 14:07:14 +0000 |
| commit | ac04abaf5a1df4c4bf48367cfbb41600289c4d78 (patch) | |
| tree | 536183ab9168de00b66908a26106bd2edef59ba5 | |
| parent | fa7b1e24e51e94f29a3d0d33a0b1dd329024d5b4 (diff) | |
| download | external_llvm-ac04abaf5a1df4c4bf48367cfbb41600289c4d78.zip external_llvm-ac04abaf5a1df4c4bf48367cfbb41600289c4d78.tar.gz external_llvm-ac04abaf5a1df4c4bf48367cfbb41600289c4d78.tar.bz2 | |
[asan] call __asan_stack_malloc_N only if use-after-return detection is enabled with the run-time option
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190939 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Transforms/Instrumentation/AddressSanitizer.cpp | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp index 2ee0f9d..8f8af20 100644 --- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -88,6 +88,9 @@ static const char *const kAsanPoisonStackMemoryName = static const char *const kAsanUnpoisonStackMemoryName = "__asan_unpoison_stack_memory"; +static const char *const kAsanOptionDetectUAR = + "__asan_option_detect_stack_use_after_return"; + // These constants must match the definitions in the run-time library. static const int kAsanStackLeftRedzoneMagic = 0xf1; static const int kAsanStackMidRedzoneMagic = 0xf2; @@ -1409,10 +1412,28 @@ void FunctionStackPoisoner::poisonStack() { Value *LocalStackBase = OrigStackBase; if (DoStackMalloc) { + // LocalStackBase = OrigStackBase + // if (__asan_option_detect_stack_use_after_return) + // LocalStackBase = __asan_stack_malloc_N(LocalStackBase, OrigStackBase); StackMallocIdx = StackMallocSizeClass(LocalStackSize); assert(StackMallocIdx <= kMaxAsanStackMallocSizeClass); - LocalStackBase = IRB.CreateCall2(AsanStackMallocFunc[StackMallocIdx], + Constant *OptionDetectUAR = F.getParent()->getOrInsertGlobal( + kAsanOptionDetectUAR, IRB.getInt32Ty()); + Value *Cmp = IRB.CreateICmpNE(IRB.CreateLoad(OptionDetectUAR), + Constant::getNullValue(IRB.getInt32Ty())); + Instruction *Term = + SplitBlockAndInsertIfThen(cast<Instruction>(Cmp), false); + BasicBlock *CmpBlock = cast<Instruction>(Cmp)->getParent(); + IRBuilder<> IRBIf(Term); + LocalStackBase = IRBIf.CreateCall2( + AsanStackMallocFunc[StackMallocIdx], ConstantInt::get(IntptrTy, LocalStackSize), OrigStackBase); + BasicBlock *SetBlock = cast<Instruction>(LocalStackBase)->getParent(); + IRB.SetInsertPoint(InsBefore); + PHINode *Phi = IRB.CreatePHI(IntptrTy, 2); + Phi->addIncoming(OrigStackBase, CmpBlock); + Phi->addIncoming(LocalStackBase, SetBlock); + LocalStackBase = Phi; } // This string will be parsed by the run-time (DescribeAddressIfStack). |