core.git: vcl/workben

[Caolán McNamara (via logerrit)]

 vcl/workben/fodt2pdffuzzer.cxx |    6 ++++++
 1 file changed, 6 insertions(+)

New commits:
commit 9d8a223b3550326d89f80124287acc071853405c
Author:     Caolán McNamara <caolan.mcnam...@collabora.com>
AuthorDate: Sun Jan 21 21:02:09 2024 +0000
Commit:     Caolán McNamara <caolan.mcnam...@collabora.com>
CommitDate: Sun Jan 21 22:04:50 2024 +0100

    Try harder to clear Use-of-uninitialized-value from LLVMFuzzerCustomMutator
    
    Try the workaround of https://github.com/google/oss-fuzz/issues/4605
    
    Change-Id: If02072f244b05e005c0c180ce689f7a919105ec4
    Reviewed-on: https://gerrit.libreoffice.org/c/core/+/162353
    Tested-by: Caolán McNamara <caolan.mcnam...@collabora.com>
    Reviewed-by: Caolán McNamara <caolan.mcnam...@collabora.com>

diff --git a/vcl/workben/fodt2pdffuzzer.cxx b/vcl/workben/fodt2pdffuzzer.cxx
index 0b6323a61ad8..91e04966c1ff 100644
--- a/vcl/workben/fodt2pdffuzzer.cxx
+++ b/vcl/workben/fodt2pdffuzzer.cxx
@@ -57,11 +57,17 @@ extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv)
 
 extern "C" size_t LLVMFuzzerMutate(uint8_t* Data, size_t Size, size_t MaxSize);
 
+extern "C" {
+__attribute__((weak)) void __msan_unpoison(const volatile void*, size_t) {}
+}
+
 extern "C" size_t LLVMFuzzerCustomMutator(uint8_t* Data, size_t Size, size_t 
MaxSize,
                                           unsigned int /*Seed*/)
 {
     size_t Ret = LLVMFuzzerMutate(Data, Size, MaxSize);
 
+    __msan_unpoison(Data, Ret);
+
     // an effort to only generate valid xml, in this fuzzer we only really care
     // about the deeper levels of turning valid input into writer layout and
     // pdf export