Re: Executable memory: some apps that work on RH9 don't on FC1

[Roland McGrath <roland redhat com>]

You can disable the exec-shield functionality globally with
/proc/sys/kernel/exec-shield, but that doesn't do anything different for an
older binary that is not marked or for a binary that is marked as requiring
executable stack.  exec-shield is always disabled for those execs.

The issue you are having is probably that malloc does not use PROT_EXEC in
its mmap-based allocations.  Executability should be enabled in the brk
area when exec-shield is disabled.  Verify the situation by looking at
/proc/PID/maps for the process in question.