[Instrumentation] Do not request sanitizers for naked functions

antoniofrighetto · antoniofrighetto · commit 9dd4fd7c0ad2 · 2024-09-15T15:19:28.000+02:00
Sanitizers instrumentation may be incompatible with naked functions,
which lack of standard prologue/epilogue.
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/HWAddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
@@ -1598,6 +1598,10 @@ void HWAddressSanitizer::sanitizeFunction(Function &F,
   if (&F == HwasanCtorFunction)
     return;
 
+  // Do not apply any instrumentation for naked functions.
+  if (F.hasFnAttribute(Attribute::Naked))
+    return;
+
   if (!F.hasFnAttribute(Attribute::SanitizeHWAddress))
     return;
 
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-naked.ll b/llvm/test/Instrumentation/sanitizers-naked.ll
@@ -11,85 +11,65 @@
 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(ptr byval(i32) %p) {
+define void @naked_function(ptr byval(i32) %p) naked {
 ; CHECK-ASAN-LABEL: define void @naked_function(
-; CHECK-ASAN-SAME: ptr byval(i32) [[P:%.*]]) {
+; CHECK-ASAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-ASAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-ASAN-NEXT:    unreachable
 ;
 ; CHECK-TSAN-LABEL: define void @naked_function(
-; CHECK-TSAN-SAME: ptr byval(i32) [[P:%.*]]) personality ptr @__gcc_personality_v0 {
-; CHECK-TSAN-NEXT:    [[TMP1:%.*]] = call ptr @llvm.returnaddress(i32 0)
-; CHECK-TSAN-NEXT:    call void @__tsan_func_entry(ptr [[TMP1]])
-; CHECK-TSAN-NEXT:    invoke void asm sideeffect "nop", ""()
-; CHECK-TSAN-NEXT:            to [[DOTNOEXC:label %.*]] unwind label %[[TSAN_CLEANUP:.*]]
-; CHECK-TSAN:       [[_NOEXC:.*:]]
+; CHECK-TSAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-TSAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-TSAN-NEXT:    unreachable
-; CHECK-TSAN:       [[TSAN_CLEANUP]]:
-; CHECK-TSAN-NEXT:    [[CLEANUP_LPAD:%.*]] = landingpad { ptr, i32 }
-; CHECK-TSAN-NEXT:            cleanup
-; CHECK-TSAN-NEXT:    call void @__tsan_func_exit()
-; CHECK-TSAN-NEXT:    resume { ptr, i32 } [[CLEANUP_LPAD]]
 ;
 ; CHECK-MSAN-LABEL: define void @naked_function(
-; CHECK-MSAN-SAME: ptr byval(i32) [[P:%.*]]) {
+; CHECK-MSAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-MSAN-NEXT:    call void @llvm.donothing()
 ; CHECK-MSAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-MSAN-NEXT:    unreachable
 ;
 ; CHECK-HWASAN-LABEL: define void @naked_function(
-; CHECK-HWASAN-SAME: ptr byval(i32) [[P:%.*]]) {
+; CHECK-HWASAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-HWASAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-HWASAN-NEXT:    unreachable
 ;
 ; CHECK-SANCOV-LABEL: define void @naked_function(
-; CHECK-SANCOV-SAME: ptr byval(i32) [[P:%.*]]) {
+; CHECK-SANCOV-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-SANCOV-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-SANCOV-NEXT:    unreachable
 ;
 ; CHECK-SANMD-LABEL: define void @naked_function(
-; CHECK-SANMD-SAME: ptr byval(i32) [[P:%.*]]) !pcsections [[META0:![0-9]+]] {
+; CHECK-SANMD-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-SANMD-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-SANMD-NEXT:    unreachable
 ;
   call void asm sideeffect "nop", ""()
   unreachable
 }
 
-define void @naked_function_with_asan(ptr byval(i32) %p) sanitize_address {
+define void @naked_function_with_asan(ptr byval(i32) %p) sanitize_address naked {
 ; CHECK-ASAN-LABEL: define void @naked_function_with_asan(
-; CHECK-ASAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR0:[0-9]+]] {
-; CHECK-ASAN-NEXT:    [[P_BYVAL:%.*]] = alloca i32, align 4
-; CHECK-ASAN-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[P_BYVAL]], ptr align 4 [[P]], i64 4, i1 false)
+; CHECK-ASAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR1:[0-9]+]] {
 ; CHECK-ASAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-ASAN-NEXT:    unreachable
 ;
   call void asm sideeffect "nop", ""()
   unreachable
 }
 
-define void @naked_function_with_tsan(ptr byval(i32) %p) sanitize_thread {
+define void @naked_function_with_tsan(ptr byval(i32) %p) sanitize_thread naked {
 ; CHECK-TSAN-LABEL: define void @naked_function_with_tsan(
-; CHECK-TSAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR1:[0-9]+]] personality ptr @__gcc_personality_v0 {
-; CHECK-TSAN-NEXT:    [[TMP1:%.*]] = call ptr @llvm.returnaddress(i32 0)
-; CHECK-TSAN-NEXT:    call void @__tsan_func_entry(ptr [[TMP1]])
-; CHECK-TSAN-NEXT:    invoke void asm sideeffect "nop", ""()
-; CHECK-TSAN-NEXT:            to [[DOTNOEXC:label %.*]] unwind label %[[TSAN_CLEANUP:.*]]
-; CHECK-TSAN:       [[_NOEXC:.*:]]
+; CHECK-TSAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR2:[0-9]+]] {
+; CHECK-TSAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-TSAN-NEXT:    unreachable
-; CHECK-TSAN:       [[TSAN_CLEANUP]]:
-; CHECK-TSAN-NEXT:    [[CLEANUP_LPAD:%.*]] = landingpad { ptr, i32 }
-; CHECK-TSAN-NEXT:            cleanup
-; CHECK-TSAN-NEXT:    call void @__tsan_func_exit()
-; CHECK-TSAN-NEXT:    resume { ptr, i32 } [[CLEANUP_LPAD]]
 ;
   call void asm sideeffect "nop", ""()
   unreachable
 }
 
-define void @naked_function_with_msan(ptr byval(i32) %p) sanitize_memory {
+define void @naked_function_with_msan(ptr byval(i32) %p) sanitize_memory naked {
 ; CHECK-MSAN-LABEL: define void @naked_function_with_msan(
-; CHECK-MSAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR2:[0-9]+]] {
+; CHECK-MSAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR3:[0-9]+]] {
 ; CHECK-MSAN-NEXT:    call void @llvm.donothing()
 ; CHECK-MSAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-MSAN-NEXT:    unreachable
@@ -98,16 +78,12 @@ define void @naked_function_with_msan(ptr byval(i32) %p) sanitize_memory {
   unreachable
 }
 
-define void @naked_function_with_hwasan(ptr byval(i32) %p) sanitize_hwaddress {
+define void @naked_function_with_hwasan(ptr byval(i32) %p) sanitize_hwaddress naked {
 ; CHECK-HWASAN-LABEL: define void @naked_function_with_hwasan(
-; CHECK-HWASAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR3:[0-9]+]] {
+; CHECK-HWASAN-SAME: ptr byval(i32) [[P:%.*]]) #[[ATTR4:[0-9]+]] personality ptr @__hwasan_personality_thunk {
 ; CHECK-HWASAN-NEXT:    call void asm sideeffect "nop", ""()
 ; CHECK-HWASAN-NEXT:    unreachable
 ;
   call void asm sideeffect "nop", ""()
   unreachable
 }
-;.
-; CHECK-SANMD: [[META0]] = !{!"sanmd_covered2!C", [[META1:![0-9]+]]}
-; CHECK-SANMD: [[META1]] = !{i64 1}
-;.
