Index: clang/lib/Driver/SanitizerArgs.cpp =================================================================== --- clang/lib/Driver/SanitizerArgs.cpp +++ clang/lib/Driver/SanitizerArgs.cpp @@ -290,10 +290,11 @@ if (Add & Fuzzer) Add |= FuzzerNoLink; - // Enable coverage if the fuzzing flag is set. + // Enable coverage and stack depth tracking if the fuzzing flag is set. if (Add & FuzzerNoLink) CoverageFeatures |= CoverageTracePCGuard | CoverageIndirCall | - CoverageTraceCmp | CoveragePCTable; + CoverageTraceCmp | CoveragePCTable | + CoverageStackDepth; Kinds |= Add; } else if (Arg->getOption().matches(options::OPT_fno_sanitize_EQ)) { Index: compiler-rt/test/fuzzer/deep-recursion.test =================================================================== --- compiler-rt/test/fuzzer/deep-recursion.test +++ compiler-rt/test/fuzzer/deep-recursion.test @@ -1,4 +1,4 @@ # Test that we can find a stack overflow -RUN: %cpp_compiler -fsanitize-coverage=stack-depth %S/DeepRecursionTest.cpp -o %t +RUN: %cpp_compiler %S/DeepRecursionTest.cpp -o %t RUN: not %t -seed=1 -runs=100000000 2>&1 | FileCheck %s CHECK: ERROR: libFuzzer: deadly signal Index: llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp =================================================================== --- llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp +++ llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp @@ -25,6 +25,7 @@ #include "llvm/IR/GlobalVariable.h" #include "llvm/IR/IRBuilder.h" #include "llvm/IR/InlineAsm.h" +#include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/Intrinsics.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/MDBuilder.h" @@ -78,6 +79,9 @@ static const char *const SanCovLowestStackName = "__sancov_lowest_stack"; +__attribute__((tls_model("initial-exec"))) +thread_local uintptr_t __sancov_lowest_stack; + static cl::opt ClCoverageLevel( "sanitizer-coverage-level", cl::desc("Sanitizer Coverage. 0: none, 1: entry block, 2: all blocks, " @@ -200,13 +204,15 @@ ArrayRef GepTraceTargets); void InjectTraceForSwitch(Function &F, ArrayRef SwitchTraceTargets); - bool InjectCoverage(Function &F, ArrayRef AllBlocks); + bool InjectCoverage(Function &F, ArrayRef AllBlocks, + bool IsLeafFunc = true); GlobalVariable *CreateFunctionLocalArrayInSection(size_t NumElements, Function &F, Type *Ty, const char *Section); void CreateFunctionLocalArrays(Function &F, ArrayRef AllBlocks); void CreatePCArray(Function &F, ArrayRef AllBlocks); - void InjectCoverageAtBlock(Function &F, BasicBlock &BB, size_t Idx); + void InjectCoverageAtBlock(Function &F, BasicBlock &BB, size_t Idx, + bool IsLeafFunc = true); Function *CreateInitCallsForSections(Module &M, const char *InitFunctionName, Type *Ty, const char *Section); std::pair @@ -491,6 +497,7 @@ &getAnalysis(F).getDomTree(); const PostDominatorTree *PDT = &getAnalysis(F).getPostDomTree(); + bool IsLeafFunc = true; for (auto &BB : F) { if (shouldInstrumentBlock(F, &BB, DT, PDT, Options)) @@ -515,10 +522,14 @@ if (Options.TraceGep) if (GetElementPtrInst *GEP = dyn_cast(&Inst)) GepTraceTargets.push_back(GEP); - } + if (Options.StackDepth) + if (isa(Inst) || + (isa(Inst) && !isa(Inst))) + IsLeafFunc = false; + } } - InjectCoverage(F, BlocksToInstrument); + InjectCoverage(F, BlocksToInstrument, IsLeafFunc); InjectCoverageForIndirectCalls(F, IndirCalls); InjectTraceForCmp(F, CmpTraceTargets); InjectTraceForSwitch(F, SwitchTraceTargets); @@ -583,11 +594,12 @@ } bool SanitizerCoverageModule::InjectCoverage(Function &F, - ArrayRef AllBlocks) { + ArrayRef AllBlocks, + bool IsLeafFunc) { if (AllBlocks.empty()) return false; CreateFunctionLocalArrays(F, AllBlocks); for (size_t i = 0, N = AllBlocks.size(); i < N; i++) - InjectCoverageAtBlock(F, *AllBlocks[i], i); + InjectCoverageAtBlock(F, *AllBlocks[i], i, IsLeafFunc); return true; } @@ -721,7 +733,8 @@ } void SanitizerCoverageModule::InjectCoverageAtBlock(Function &F, BasicBlock &BB, - size_t Idx) { + size_t Idx, + bool IsLeafFunc) { BasicBlock::iterator IP = BB.getFirstInsertionPt(); bool IsEntryBB = &BB == &F.getEntryBlock(); DebugLoc EntryLoc; @@ -760,7 +773,7 @@ SetNoSanitizeMetadata(Load); SetNoSanitizeMetadata(Store); } - if (Options.StackDepth && IsEntryBB) { + if (Options.StackDepth && IsEntryBB && !IsLeafFunc) { // Check stack depth. If it's the deepest so far, record it. Function *GetFrameAddr = Intrinsic::getDeclaration(F.getParent(), Intrinsic::frameaddress); @@ -771,7 +784,9 @@ auto IsStackLower = IRB.CreateICmpULT(FrameAddrInt, LowestStack); auto ThenTerm = SplitBlockAndInsertIfThen(IsStackLower, &*IP, false); IRBuilder<> ThenIRB(ThenTerm); - ThenIRB.CreateStore(FrameAddrInt, SanCovLowestStack); + auto Store = ThenIRB.CreateStore(FrameAddrInt, SanCovLowestStack); + SetNoSanitizeMetadata(LowestStack); + SetNoSanitizeMetadata(Store); } } Index: llvm/test/Instrumentation/SanitizerCoverage/stack-depth.ll =================================================================== --- llvm/test/Instrumentation/SanitizerCoverage/stack-depth.ll +++ llvm/test/Instrumentation/SanitizerCoverage/stack-depth.ll @@ -1,9 +1,9 @@ ; This check verifies that stack depth instrumentation works correctly. ; RUN: opt < %s -sancov -sanitizer-coverage-level=1 \ -; RUN: -sanitizer-coverage-stack-depth -S | FileCheck %s --enable-var-scope +; RUN: -sanitizer-coverage-stack-depth -S | FileCheck %s ; RUN: opt < %s -sancov -sanitizer-coverage-level=3 \ ; RUN: -sanitizer-coverage-stack-depth -sanitizer-coverage-trace-pc-guard \ -; RUN: -S | FileCheck %s --enable-var-scope +; RUN: -S | FileCheck %s target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" @@ -14,13 +14,8 @@ define i32 @foo() { entry: ; CHECK-LABEL: define i32 @foo -; CHECK: [[framePtr:%[^ \t]+]] = call i8* @llvm.frameaddress(i32 0) -; CHECK: [[frameInt:%[^ \t]+]] = ptrtoint i8* [[framePtr]] to [[$intType:i[0-9]+]] -; CHECK: [[lowest:%[^ \t]+]] = load [[$intType]], [[$intType]]* @__sancov_lowest_stack -; CHECK: [[cmp:%[^ \t]+]] = icmp ult [[$intType]] [[frameInt]], [[lowest]] -; CHECK: br i1 [[cmp]], label %[[ifLabel:[^ \t]+]], label -; CHECK: