Pointer guard for static binaries?

[Ulrich Drepper]

Roland McGrath wrote:
> It's not clear to me why x86-64 should put the global
> pointer-guard value in tcbhead_t, given that's it's only used in libc.so
> and so a local symbol there could be used.

Because it is so easy to access the value it is a weakness.  The TCB
address is not at a constant relative address to the libc code and
therefore accessing the value is much harder.

-- 
➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖

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