Message-ID: <4060E24C.9000507@redhat.com>
Date: Tue, 23 Mar 2004 17:20:12 -0800
From: Ulrich Drepper <drepper@redhat.com>
Organization: Red Hat, Inc.
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To: davidm@hpl.hp.com
CC: linux-kernel@vger.kernel.org
Subject: Re: Non-Exec stack patches
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David Mosberger wrote:

> I guess I never quiet understood why an entire program header is
> needed for this, but that's just me.

This just means you haven't looked at the problem.

First, the ELF bits are limited and very crowded on some archs.  There
is no central assignment so conflicts will happen.

And one single bit does not cut it.  If you'd take a look, the
PT_GNU_STACK entry's permissions field specifies what permissions the
stack must have, not the presence of the field.  So at least two bits
are needed which only adds to the problems of finding appropriate bits.

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