[Instrumentation] Do not run sanitizers for naked functions

Sanitizers instrumentation is incompatible with naked functions, which are expected to contain only inline asm.
llvm · Sep 13, 2024 · d76f9d7 · d76f9d7
1 parent c0e308b
commit d76f9d7
Show file tree

Hide file tree

Showing 6 changed files with 65 additions and 1 deletion.
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -2960,6 +2960,10 @@ bool AddressSanitizer::instrumentFunction(Function &F,
 
   bool FunctionModified = false;
 
+  // Do not apply any instrumentation for naked functions.
+  if (F.hasFnAttribute(Attribute::Naked))
+    return FunctionModified;
+
   // If needed, insert __asan_init before checking for SanitizeAddress attr.
   // This function needs to be called even if the function body is not
   // instrumented.

diff --git a/llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp
@@ -1545,8 +1545,9 @@ bool DataFlowSanitizer::runImpl(
   SmallPtrSet<Function *, 2> FnsWithForceZeroLabel;
   SmallPtrSet<Constant *, 1> PersonalityFns;
   for (Function &F : M)
+    // Do not apply any instrumentation for naked functions or if disabled.
     if (!F.isIntrinsic() && !DFSanRuntimeFunctions.contains(&F) &&
-        !LibAtomicFunction(F) &&
+        !LibAtomicFunction(F) && !F.hasFnAttribute(Attribute::Naked) &&
         !F.hasFnAttribute(Attribute::DisableSanitizerInstrumentation)) {
       FnsToInstrument.push_back(&F);
       if (F.hasPersonalityFn())

diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -6078,6 +6078,10 @@ bool MemorySanitizer::sanitizeFunction(Function &F, TargetLibraryInfo &TLI) {
   if (!CompileKernel && F.getName() == kMsanModuleCtorName)
     return false;
 
+  // Do not apply any instrumentation for naked functions.
+  if (F.hasFnAttribute(Attribute::Naked))
+    return false;
+
   if (F.hasFnAttribute(Attribute::DisableSanitizerInstrumentation))
     return false;
 

diff --git a/llvm/lib/Transforms/Instrumentation/SanitizerBinaryMetadata.cpp b/llvm/lib/Transforms/Instrumentation/SanitizerBinaryMetadata.cpp
@@ -258,6 +258,9 @@ bool SanitizerBinaryMetadata::run() {
 void SanitizerBinaryMetadata::runOn(Function &F, MetadataInfoSet &MIS) {
   if (F.empty())
     return;
+  // Do not apply any instrumentation for naked functions.
+  if (F.hasFnAttribute(Attribute::Naked))
+    return;
   if (F.hasFnAttribute(Attribute::DisableSanitizerInstrumentation))
     return;
   if (Ignorelist && Ignorelist->inSection("metadata", "fun", F.getName()))

diff --git a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
@@ -629,6 +629,9 @@ void ModuleSanitizerCoverage::instrumentFunction(Function &F) {
     return;
   if (Blocklist && Blocklist->inSection("coverage", "fun", F.getName()))
     return;
+  // Do not apply any instrumentation for naked functions.
+  if (F.hasFnAttribute(Attribute::Naked))
+    return;
   if (F.hasFnAttribute(Attribute::NoSanitizeCoverage))
     return;
   if (F.hasFnAttribute(Attribute::DisableSanitizerInstrumentation))

diff --git a/llvm/test/Instrumentation/sanitizers-no-naked.ll b/llvm/test/Instrumentation/sanitizers-no-naked.ll
@@ -0,0 +1,49 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -passes=asan -S | FileCheck %s
+; RUN: opt < %s -passes=tsan -S | FileCheck %s
+; RUN: opt < %s -passes=dfsan -dfsan-track-origins=1  -S | FileCheck %s
+; RUN: opt < %s -passes='module(sancov-module)' -sanitizer-coverage-level=3 -sanitizer-coverage-control-flow -S | FileCheck %s
+; RUN: opt < %s -passes='module(sanmd-module)' -sanitizer-metadata-atomics -S | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @naked_function() naked {
+; CHECK-LABEL: define void @naked_function(
+; CHECK-SAME: ) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:    call void asm sideeffect "nop", ""()
+; CHECK-NEXT:    unreachable
+;
+  call void asm sideeffect "nop", ""()
+  unreachable
+}
+
+define void @naked_function_with_asan() sanitize_address naked {
+; CHECK-LABEL: define void @naked_function_with_asan(
+; CHECK-SAME: ) #[[ATTR1:[0-9]+]] {
+; CHECK-NEXT:    call void asm sideeffect "nop", ""()
+; CHECK-NEXT:    unreachable
+;
+  call void asm sideeffect "nop", ""()
+  unreachable
+}
+
+define void @naked_function_with_tsan() sanitize_thread naked {
+; CHECK-LABEL: define void @naked_function_with_tsan(
+; CHECK-SAME: ) #[[ATTR2:[0-9]+]] {
+; CHECK-NEXT:    call void asm sideeffect "nop", ""()
+; CHECK-NEXT:    unreachable
+;
+  call void asm sideeffect "nop", ""()
+  unreachable
+}
+
+define void @naked_function_with_msan() sanitize_memory naked {
+; CHECK-LABEL: define void @naked_function_with_msan(
+; CHECK-SAME: ) #[[ATTR3:[0-9]+]] {
+; CHECK-NEXT:    call void asm sideeffect "nop", ""()
+; CHECK-NEXT:    unreachable
+;
+  call void asm sideeffect "nop", ""()
+  unreachable
+}