Hi, I looked over the "ClusterFuzz-External via monorail" emails and found some "real" issues. But in general it is hard to determined what this cluster is complaining about. The emails are somewhat opaque and don't contain proper backtraces (with file and line numbers), nor do they contain any context on how the target was configured or with which flags or arguments any fuzzing testcases were run.
The following fixes should fix reading of some broken ar archives and misaligned access of the section zero Shdr for mmaped ELF files where the start of the Elf image is at some offset from the start of the map. [PATCH 1/2] libelf: Take map offset into account for Shdr alignment [PATCH 2/2] libelf: Make sure ar_size starts with a digit before https://code.wildebeest.org/git/user/mjw/elfutils/log/?h=fuzz I haven't been able to replicate any other issues locally. I don't really trust the msan instrumentation, better use valgrind (although both might be too slow for fuzzing). There are also some other misaligned type access checks reported by ubsan, but I don't know if that is because of ALLOW_UNALIGNED is still defined or not (when configuring with --enable-analyze-undefined ALLOW_UNALIGNED is not defined, otherwise it is for some arches, including x86_64). I don't mind getting rid of ALLOW_UNALIGNED, but it is some work. Cheers, Mark
