Date: Tue, 14 Aug 2007 23:42:06 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Andi Kleen <andi@firstfloor.org>
Cc: Hajime Inoue <hinoue@ccsl.carleton.ca>, linux-kernel@vger.kernel.org
Subject: Re: System call interposition/unprotecting the table
Message-ID: <20070814234206.76121d02@the-village.bc.nu>
In-Reply-To: <p73zm0tnbf8.fsf@bingen.suse.de>
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> So even with Alan's hypervisor support the whole thing would be still
> quite holey.  The argument of raising the bar also doesn't seem very

Its materially harder, especially with the hypervisor.

> convincing to me, because attackers reuse code too and it's enough
> when someone publishes such code once, then they can cut'n'paste
> it into any exploits forever.

Then you fix the specific case and the game continues.

> In general the .data protection is only considered a debugging
> feature. I don't know why Fedora enables it in their production
> kernels.

That would be because we think you are wrong 8)

Alan
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