diff options
| -rw-r--r-- | lib/Transforms/Instrumentation/MemorySanitizer.cpp | 24 | ||||
| -rw-r--r-- | test/Instrumentation/MemorySanitizer/msan_basic.ll | 35 |
2 files changed, 49 insertions, 10 deletions
diff --git a/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/lib/Transforms/Instrumentation/MemorySanitizer.cpp index a3a688d..8e2baef 100644 --- a/lib/Transforms/Instrumentation/MemorySanitizer.cpp +++ b/lib/Transforms/Instrumentation/MemorySanitizer.cpp @@ -425,6 +425,8 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> { ValueMap<Value*, Value*> ShadowMap, OriginMap; bool InsertChecks; bool LoadShadow; + bool PoisonStack; + bool PoisonUndef; OwningPtr<VarArgHelper> VAHelper; struct ShadowOriginAndInsertPoint { @@ -440,10 +442,13 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> { MemorySanitizerVisitor(Function &F, MemorySanitizer &MS) : F(F), MS(MS), VAHelper(CreateVarArgHelper(F, MS, *this)) { - LoadShadow = InsertChecks = - !MS.BL->isIn(F) && - F.getAttributes().hasAttribute(AttributeSet::FunctionIndex, - Attribute::SanitizeMemory); + bool SanitizeFunction = !MS.BL->isIn(F) && F.getAttributes().hasAttribute( + AttributeSet::FunctionIndex, + Attribute::SanitizeMemory); + InsertChecks = SanitizeFunction; + LoadShadow = SanitizeFunction; + PoisonStack = SanitizeFunction && ClPoisonStack; + PoisonUndef = SanitizeFunction && ClPoisonUndef; DEBUG(if (!InsertChecks) dbgs() << "MemorySanitizer is not inserting checks into '" @@ -744,7 +749,7 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> { return Shadow; } if (UndefValue *U = dyn_cast<UndefValue>(V)) { - Value *AllOnes = ClPoisonUndef ? getPoisonedShadow(V) : getCleanShadow(V); + Value *AllOnes = PoisonUndef ? getPoisonedShadow(V) : getCleanShadow(V); DEBUG(dbgs() << "Undef: " << *U << " ==> " << *AllOnes << "\n"); (void)U; return AllOnes; @@ -1704,20 +1709,19 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> { void visitAllocaInst(AllocaInst &I) { setShadow(&I, getCleanShadow(&I)); - if (!ClPoisonStack) return; IRBuilder<> IRB(I.getNextNode()); uint64_t Size = MS.TD->getTypeAllocSize(I.getAllocatedType()); - if (ClPoisonStackWithCall) { + if (PoisonStack && ClPoisonStackWithCall) { IRB.CreateCall2(MS.MsanPoisonStackFn, IRB.CreatePointerCast(&I, IRB.getInt8PtrTy()), ConstantInt::get(MS.IntptrTy, Size)); } else { Value *ShadowBase = getShadowPtr(&I, Type::getInt8PtrTy(*MS.C), IRB); - IRB.CreateMemSet(ShadowBase, IRB.getInt8(ClPoisonStackPattern), - Size, I.getAlignment()); + Value *PoisonValue = IRB.getInt8(PoisonStack ? ClPoisonStackPattern : 0); + IRB.CreateMemSet(ShadowBase, PoisonValue, Size, I.getAlignment()); } - if (MS.TrackOrigins) { + if (PoisonStack && MS.TrackOrigins) { setOrigin(&I, getCleanOrigin()); SmallString<2048> StackDescriptionStorage; raw_svector_ostream StackDescription(StackDescriptionStorage); diff --git a/test/Instrumentation/MemorySanitizer/msan_basic.ll b/test/Instrumentation/MemorySanitizer/msan_basic.ll index 3a8092b..4fa0319 100644 --- a/test/Instrumentation/MemorySanitizer/msan_basic.ll +++ b/test/Instrumentation/MemorySanitizer/msan_basic.ll @@ -638,6 +638,41 @@ declare void @bar() ; CHECK: ret i32 +; Test that stack allocations are unpoisoned in functions missing +; sanitize_memory attribute + +define i32 @NoSanitizeMemoryAlloca() { +entry: + %p = alloca i32, align 4 + %x = call i32 @NoSanitizeMemoryAllocaHelper(i32* %p) + ret i32 %x +} + +declare i32 @NoSanitizeMemoryAllocaHelper(i32* %p) + +; CHECK: @NoSanitizeMemoryAlloca +; CHECK: call void @llvm.memset.p0i8.i64(i8* {{.*}}, i8 0, i64 4, i32 4, i1 false) +; CHECK: call i32 @NoSanitizeMemoryAllocaHelper(i32* +; CHECK: ret i32 + + +; Test that undef is unpoisoned in functions missing +; sanitize_memory attribute + +define i32 @NoSanitizeMemoryUndef() { +entry: + %x = call i32 @NoSanitizeMemoryUndefHelper(i32 undef) + ret i32 %x +} + +declare i32 @NoSanitizeMemoryUndefHelper(i32 %x) + +; CHECK: @NoSanitizeMemoryAlloca +; CHECK: store i32 0, i32* {{.*}} @__msan_param_tls +; CHECK: call i32 @NoSanitizeMemoryUndefHelper(i32 undef) +; CHECK: ret i32 + + ; Test argument shadow alignment define <2 x i64> @ArgumentShadowAlignment(i64 %a, <2 x i64> %b) sanitize_memory { |