[compiler-rt] 4688df6 - Avoid partial munmap (#92109)

[via llvm-commits]

Author: Stephan Bergmann
Date: 2024-05-15T08:58:14+02:00
New Revision: 4688df68f9d022dd8bc102675a9e86ad274355d6

URL: https://github.com/llvm/llvm-project/commit/4688df68f9d022dd8bc102675a9e86ad274355d6
DIFF: https://github.com/llvm/llvm-project/commit/4688df68f9d022dd8bc102675a9e86ad274355d6.diff

LOG: Avoid partial munmap (#92109)

...which caused issues like

> ==42==ERROR: AddressSanitizer failed to deallocate 0x32 (50) bytes at
address 0x117e0000 (error code: 28)
> ==42==Cannot dump memory map on emscriptenAddressSanitizer: CHECK
failed: sanitizer_common.cpp:81 "((0 && "unable to unmmap")) != (0)"
(0x0, 0x0) (tid=288045824)
> #0 0x14f73b0c in __asan::CheckUnwind()+0x14f73b0c
(this.program+0x14f73b0c)
> #1 0x14f8a3c2 in __sanitizer::CheckFailed(char const*, int, char
const*, unsigned long long, unsigned long long)+0x14f8a3c2
(this.program+0x14f8a3c2)
> #2 0x14f7d6e1 in __sanitizer::ReportMunmapFailureAndDie(void*,
unsigned long, int, bool)+0x14f7d6e1 (this.program+0x14f7d6e1)
> #3 0x14f81fbd in __sanitizer::UnmapOrDie(void*, unsigned
long)+0x14f81fbd (this.program+0x14f81fbd)
> #4 0x14f875df in __sanitizer::SuppressionContext::ParseFromFile(char
const*)+0x14f875df (this.program+0x14f875df)
> #5 0x14f74eab in __asan::InitializeSuppressions()+0x14f74eab
(this.program+0x14f74eab)
> #6 0x14f73a1a in __asan::AsanInitInternal()+0x14f73a1a
(this.program+0x14f73a1a)

when trying to use an ASan suppressions file under Emscripten: Even
though it would be considered OK by SUSv4, the Emscripten runtime states
"We don't support partial munmapping" (see

<https://github.com/emscripten-core/emscripten/commit/f4115eb2c36bac741685300273cb9fa186d719e1>
"Implement MAP_ANONYMOUS on top of malloc in STANDALONE_WASM mode
(#16289)").

Co-authored-by: Stephan Bergmann <stephan.bergmann at allotropia.de>

Added: 
    

Modified: 
    compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cpp

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cpp
index 9c8c4bf9d1a48..62ebbb38feaed 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_suppressions.cpp
@@ -86,7 +86,7 @@ void SuppressionContext::ParseFromFile(const char *filename) {
   }
 
   Parse(file_contents);
-  UnmapOrDie(file_contents, contents_size);
+  UnmapOrDie(file_contents, buffer_size);
 }
 
 bool SuppressionContext::Match(const char *str, const char *type,