Author: Sami Tolvanen Date: 2024-08-20T16:51:16-07:00 New Revision: e1c36bde0551977d4b2efae032af6dfc4b2b3936
URL: https://github.com/llvm/llvm-project/commit/e1c36bde0551977d4b2efae032af6dfc4b2b3936 DIFF: https://github.com/llvm/llvm-project/commit/e1c36bde0551977d4b2efae032af6dfc4b2b3936.diff LOG: Fix KCFI types for generated functions with integer normalization (#104826) With -fsanitize-cfi-icall-experimental-normalize-integers, Clang appends ".normalized" to KCFI types in CodeGenModule::CreateKCFITypeId, which changes type hashes also for functions that don't have integer types in their signatures. However, llvm::setKCFIType does not take integer normalization into account, which means LLVM generated functions with KCFI types, e.g. sanitizer constructors, will fail KCFI checks when integer normalization is enabled in Clang. Add a cfi-normalize-integers module flag to indicate integer normalization is used, and append ".normalized" to KCFI types also in llvm::setKCFIType to fix the type mismatch. Added: llvm/test/Transforms/GCOVProfiling/kcfi-normalize.ll Modified: clang/lib/CodeGen/CodeGenModule.cpp clang/test/CodeGen/kcfi-normalize.c llvm/lib/Transforms/Utils/ModuleUtils.cpp llvm/test/Transforms/GCOVProfiling/kcfi.ll Removed: ################################################################################ diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index 0b61ef0f89989c..0d3b896af8aa39 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -1134,6 +1134,11 @@ void CodeGenModule::Release() { CodeGenOpts.SanitizeCfiCanonicalJumpTables); } + if (CodeGenOpts.SanitizeCfiICallNormalizeIntegers) { + getModule().addModuleFlag(llvm::Module::Override, "cfi-normalize-integers", + 1); + } + if (LangOpts.Sanitize.has(SanitizerKind::KCFI)) { getModule().addModuleFlag(llvm::Module::Override, "kcfi", 1); // KCFI assumes patchable-function-prefix is the same for all indirectly diff --git a/clang/test/CodeGen/kcfi-normalize.c b/clang/test/CodeGen/kcfi-normalize.c index 7660c908a7bdd5..b9150e88f6ab5f 100644 --- a/clang/test/CodeGen/kcfi-normalize.c +++ b/clang/test/CodeGen/kcfi-normalize.c @@ -28,6 +28,7 @@ void baz(void (*fn)(int, int, int), int arg1, int arg2, int arg3) { fn(arg1, arg2, arg3); } +// CHECK: ![[#]] = !{i32 4, !"cfi-normalize-integers", i32 1} // CHECK: ![[TYPE1]] = !{i32 -1143117868} // CHECK: ![[TYPE2]] = !{i32 -460921415} // CHECK: ![[TYPE3]] = !{i32 -333839615} diff --git a/llvm/lib/Transforms/Utils/ModuleUtils.cpp b/llvm/lib/Transforms/Utils/ModuleUtils.cpp index 309cf8e70b979c..7249571f344938 100644 --- a/llvm/lib/Transforms/Utils/ModuleUtils.cpp +++ b/llvm/lib/Transforms/Utils/ModuleUtils.cpp @@ -205,11 +205,13 @@ void llvm::setKCFIType(Module &M, Function &F, StringRef MangledType) { // Matches CodeGenModule::CreateKCFITypeId in Clang. LLVMContext &Ctx = M.getContext(); MDBuilder MDB(Ctx); - F.setMetadata( - LLVMContext::MD_kcfi_type, - MDNode::get(Ctx, MDB.createConstant(ConstantInt::get( - Type::getInt32Ty(Ctx), - static_cast<uint32_t>(xxHash64(MangledType)))))); + std::string Type = MangledType.str(); + if (M.getModuleFlag("cfi-normalize-integers")) + Type += ".normalized"; + F.setMetadata(LLVMContext::MD_kcfi_type, + MDNode::get(Ctx, MDB.createConstant(ConstantInt::get( + Type::getInt32Ty(Ctx), + static_cast<uint32_t>(xxHash64(Type)))))); // If the module was compiled with -fpatchable-function-entry, ensure // we use the same patchable-function-prefix. if (auto *MD = mdconst::extract_or_null<ConstantInt>( diff --git a/llvm/test/Transforms/GCOVProfiling/kcfi-normalize.ll b/llvm/test/Transforms/GCOVProfiling/kcfi-normalize.ll new file mode 100644 index 00000000000000..19122b920d1ca4 --- /dev/null +++ b/llvm/test/Transforms/GCOVProfiling/kcfi-normalize.ll @@ -0,0 +1,35 @@ +;; Ensure __llvm_gcov_(writeout|reset|init) have the correct !kcfi_type +;; with integer normalization. +; RUN: mkdir -p %t && cd %t +; RUN: opt < %s -S -passes=insert-gcov-profiling | FileCheck %s + +target triple = "x86_64-unknown-linux-gnu" + +define dso_local void @empty() !dbg !5 { +entry: + ret void, !dbg !8 +} + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!3, !4, !9, !10} + +!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "a.c", directory: "") +!2 = !{} +!3 = !{i32 7, !"Dwarf Version", i32 5} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = distinct !DISubprogram(name: "empty", scope: !1, file: !1, line: 1, type: !6, scopeLine: 1, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2) +!6 = !DISubroutineType(types: !7) +!7 = !{null} +!8 = !DILocation(line: 2, column: 1, scope: !5) +!9 = !{i32 4, !"kcfi", i32 1} +!10 = !{i32 4, !"cfi-normalize-integers", i32 1} + +; CHECK: define internal void @__llvm_gcov_writeout() +; CHECK-SAME: !kcfi_type ![[#TYPE:]] +; CHECK: define internal void @__llvm_gcov_reset() +; CHECK-SAME: !kcfi_type ![[#TYPE]] +; CHECK: define internal void @__llvm_gcov_init() +; CHECK-SAME: !kcfi_type ![[#TYPE]] + +; CHECK: ![[#TYPE]] = !{i32 -440107680} diff --git a/llvm/test/Transforms/GCOVProfiling/kcfi.ll b/llvm/test/Transforms/GCOVProfiling/kcfi.ll index b25f40f05d5bc4..1b97d25294cd65 100644 --- a/llvm/test/Transforms/GCOVProfiling/kcfi.ll +++ b/llvm/test/Transforms/GCOVProfiling/kcfi.ll @@ -24,8 +24,10 @@ entry: !9 = !{i32 4, !"kcfi", i32 1} ; CHECK: define internal void @__llvm_gcov_writeout() -; CHECK-SAME: !kcfi_type +; CHECK-SAME: !kcfi_type ![[#TYPE:]] ; CHECK: define internal void @__llvm_gcov_reset() -; CHECK-SAME: !kcfi_type +; CHECK-SAME: !kcfi_type ![[#TYPE]] ; CHECK: define internal void @__llvm_gcov_init() -; CHECK-SAME: !kcfi_type +; CHECK-SAME: !kcfi_type ![[#TYPE]] + +; CHECK: ![[#TYPE]] = !{i32 -1522505972} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
