To: Jakub Jelinek <jakub@redhat.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Non-Exec stack patches
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From: Andi Kleen <ak@suse.de>
Date: 24 Mar 2004 18:49:21 +0100
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Jakub Jelinek <jakub@redhat.com> writes:
> 
> Nope.  Think about multithreaded apps.  Furthermore, getting the exact
> extents of the particular stack is difficult to find for applications,
> but e.g. the threading library has to know such things.

It's actually not that difficult. You just have to read /proc/self/maps
and check for the mapping of your current stack pointer.
For the main stack GROWSDOWN will inherit the x or nx on growing
down.

And cache a flag about this in a TLS variable.

-Andi
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