Stas Sergeev wrote:
Even though the access(X_OK) is mostly not needed as the execve() would fail anyway, this is not the case for ld.so. I think it would be a good idea for ld.so to start using the access(R_OK | X_OK) before open().
Not really. If you want to do something along those lines it would be better to add a new open flag called something like O_RDEXONLY which would require r-x effective file permissions, and allow PROT_READ|PROT_EXEC mmaps (though for that to be really useful, you'd need to make an O_RDONLY fd not allow PROT_EXEC mmaps, which would break a few things).
access() is just plain racy, and can't be used safely for any kind of permission/security check.
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