[31253] in bugtraq
Re: Buffer overflow prevention
daemon@ATHENA.MIT.EDU (Mariusz Woloszyn)
Mon Aug 18 15:09:02 2003
Date: Mon, 18 Aug 2003 20:01:51 +0200 (EEST)
From: Mariusz Woloszyn <emsi@ipartners.pl>
To: pageexec@freemail.hu
Cc: bugtraq@securityfocus.com
In-Reply-To: <3F40B615.4644.E269C65@localhost>
Message-ID: <Pine.LNX.4.50.0308181957130.2830-100000@dzyngiel.ipartners.pl>
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On Mon, 18 Aug 2003 pageexec@freemail.hu wrote:
> > Anyways, on an i386 you can do W^X somewhat. Not as perfectly as you
> > can on cpus that have a per-page X bit...
>
> You are wrong again, PaX provides perfect per-page non-executable pages
> using segmentation (SEGMEXEC), there are no restrictions on the ordering
> of data/code pages like in OpenBSD.
>
BTW: have anyone tried to talk wih Linus about implementing some PaX (or
even GR) functionality in official Kernels?
I know that the argument for not implementing Solar Designer's
nonexecutable stack patch in official kernel was that it is easily
bypassable, so what about PaX???
I hate seeing GOT and other segments rwx nowdays (while it's marked as r-x
it IS executable).
--
Mariusz Wołoszyn
Internet Security Specialist, GTS - Internet Partners
