Date: Tue, 14 Aug 2007 12:34:25 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Avi Kivity <avi@argo.co.il>
Cc: hinoue@ccsl.carleton.ca, linux-kernel@vger.kernel.org
Subject: Re: System call interposition/unprotecting the table
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On Tue, 14 Aug 2007 08:12:29 +0300
Avi Kivity <avi@argo.co.il> wrote:

> Alan Cox wrote:
> > This is to protect it from being changed by an attacker or someone trying
> > to do strange and bogus things to the kernel.
> >   
> 
> Someone who apparently hasn't heard of vmap(), etc.
> 
> It's a debug aid at best.

You assume the average attacker is smart. Fortunately this isn't true,
although some certainly are. For guests however we can push this further
as a hypervisor can implement 'irrevocably read only' pages for a guest.
Something we don't currently do but should.

Alan
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