[Darwin][ASan][Test] Create a noinlined wrapper function for reliable suppression in test.

[padriff]

CFStringCreateWithBytes may not always appear on stack due to optimizations. Create a wrapper function for the purposes of testing suppression files that will always appear on stack for test stability.

Also necessary to disable leaks to pass on Apple Silicon.

rdar://144800068

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[llvmbot]

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: Paddy McDonald (padriff)

Changes

CFStringCreateWithBytes may not always appear on stack due to optimizations. Create a wrapper function for the purposes of testing suppression files that will always appear on stack for test stability.

Also necessary to disable leaks to pass on Apple Silicon.

rdar://144800068

---

Full diff: https://github.com/llvm/llvm-project/pull/131247.diff

1 Files Affected:

• (modified) compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp (+10-5)

diff --git a/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp b/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
index 966f21346e4fe..50dfd1e2e332b 100644
--- a/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
+++ b/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
@@ -3,8 +3,8 @@
 // RUN: not %run %t 2>&1 | FileCheck --check-prefix=CHECK-CRASH %s
 
 // Check that suppressing a function name works within a no-fork sandbox
-// RUN: echo "interceptor_via_fun:CFStringCreateWithBytes" > %t.supp
-// RUN: %env_asan_opts=suppressions='"%t.supp"' \
+// RUN: echo "interceptor_via_fun:createCFString" > %t.supp
+// RUN: %env_asan_opts=suppressions='"%t.supp"':verbostiy=1:  \
 // RUN:   sandbox-exec -p '(version 1)(allow default)(deny process-fork)' \
 // RUN:   %run %t 2>&1 | FileCheck --check-prefix=CHECK-IGNORE %s
 
@@ -13,12 +13,17 @@
 
 #include <CoreFoundation/CoreFoundation.h>
 
+// Use a noinline + disable_tail_calls wrapper function to suppress to stabilize test.
+__attribute__((noinline)) __attribute__((disable_tail_calls)) CFStringRef
+createCFString(const unsigned char *bytes, CFIndex length) {
+  return CFStringCreateWithBytes(kCFAllocatorDefault, bytes, length,
+                                 kCFStringEncodingUTF8, FALSE);
+}
+
 int main() {
   char *a = (char *)malloc(6);
   strcpy(a, "hello");
-  CFStringRef str =
-      CFStringCreateWithBytes(kCFAllocatorDefault, (unsigned char *)a, 10,
-                              kCFStringEncodingUTF8, FALSE);  // BOOM
+  CFStringRef str = createCFString((unsigned char *)a, 10); // BOOM
   fprintf(stderr, "Ignored.\n");
   free(a);
   CFRelease(str);

[thetruestblue]

nit: __attribute__((noinline, disable_tail_calls))

also this feels a bit like overkill.

[padriff]

The two optimizations that could break the test are inlining of the function and if the function were optimized to tail call to the callee. Admittedly I don't think the current optimizer will add a tail call as the callee is external to the binary, but if we are explicitly disabling one that can break it then shouldn't we do both?

[thetruestblue]

approved, but please address nits

[yln]

LGTM, with nits, thanks!

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[aeubanks]

this seems to have broken the test on x86-64 macs:

 ******************** TEST 'AddressSanitizer-x86_64-darwin :: TestCases/Darwin/suppressions-sandbox.cpp' FAILED ********************
 Exit Code: 1
 
 Command Output (stderr):
 --
 RUN: at line 2: /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/./bin/clang  --driver-mode=g++ -fsanitize=address -mno-omit-leaf-frame-pointer -fno-omit-frame-pointer -fno-optimize-sibling-calls -gline-tables-only  -arch x86_64 -stdlib=libc++ -mmacosx-version-min=10.12 -isysroot /Volumes/Work/s/w/ir/cache/osx_sdk/XCode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.2.sdk -mlinker-version=1115.7.3  -shared-libasan -O0 /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp -o /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp -framework Foundation
 + /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/./bin/clang --driver-mode=g++ -fsanitize=address -mno-omit-leaf-frame-pointer -fno-omit-frame-pointer -fno-optimize-sibling-calls -gline-tables-only -arch x86_64 -stdlib=libc++ -mmacosx-version-min=10.12 -isysroot /Volumes/Work/s/w/ir/cache/osx_sdk/XCode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.2.sdk -mlinker-version=1115.7.3 -shared-libasan -O0 /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp -o /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp -framework Foundation
 RUN: at line 3: not  /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp 2>&1 | FileCheck --check-prefix=CHECK-CRASH /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
 + not /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp
 + FileCheck --check-prefix=CHECK-CRASH /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
 RUN: at line 6: echo "interceptor_via_fun:createCFString" > /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp.supp
 + echo interceptor_via_fun:createCFString
 RUN: at line 7: env ASAN_OPTIONS=abort_on_error=0:log_to_syslog=0:detect_leaks=1:suppressions='"/Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp.supp"'    sandbox-exec -p '(version 1)(allow default)(deny process-fork)'     /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp 2>&1 | FileCheck --check-prefix=CHECK-IGNORE /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
 + env 'ASAN_OPTIONS=abort_on_error=0:log_to_syslog=0:detect_leaks=1:suppressions="/Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp.supp"' sandbox-exec -p '(version 1)(allow default)(deny process-fork)' /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm-build/Release+Asserts/runtimes/runtimes-bins/compiler-rt/test/asan/X86_64DarwinConfig/TestCases/Darwin/Output/suppressions-sandbox.cpp.tmp
 + FileCheck --check-prefix=CHECK-IGNORE /Volumes/Work/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/test/asan/TestCases/Darwin/suppressions-sandbox.cpp
 
 --

the test logs are not very helpful though...

[aeubanks]

also started failing at https://green.lab.llvm.org/job/llvm.org/job/clang-stage1-RA/3852/ with this PR in the blamelist, can we revert this?

[aeubanks]

I've reverted this in a65cbc4, feel free to reland once you've figured out the x86-64 issue

also I'm surprised this is necessary given the test uses -O0

[padriff]

@aeubanks - thanks, I was working on a fix yesterday to address this. The issue is related to the FIXME comment in DemangleCXXABI in compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp.
LeakSanitizer was firing on a leak caused by demangling the symbol for the suppressed function name.

The tail call optimization that breaks the test on AS is in the external code rather than in the test code, so the -O0 doesn't impact that.

Updated PR which also moves the suppression to a non-sanitized dylib