libasan: prctl interceptor uses wrong type for calling prctl implementation - Githubissues

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libasan: prctl interceptor uses wrong type for calling prctl implementation #80497

Open fweimer-rh opened 8 months ago

fweimer-rh commented 8 months ago

The prctl function in glibc is variadic, yet libasan calls it with a fixed argument list. This causes stack corruption on powerpc64le-linux-gnu with glibc 2.32 or later because the prctl implementation assumes that the parameter save area has been set up by the caller, which only happens on variadic calls.

References:

Bug 29770 - prctl does not match manual page ABI on powerpc64le-linux-gnu
Bug 113728 - libasan uses incorrect prctl prototype

I don't know if I can get the ABI change reverted on the glibc side.

fweimer-rh commented 8 months ago

This has been worked around in glibc:

Linux: Switch back to assembly syscall wrapper for prctl (bug 29770)