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	Thu, 12 May 2011 19:37:23 +1000 (EST)
Date: Thu, 12 May 2011 02:24:24 -0700
From: Kees Cook <kees.cook@canonical.com>
To: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH 3/5] v2 seccomp_filters: Enable ftrace-based system call
	filtering
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Cc: linux-mips@linux-mips.org, linux-sh@vger.kernel.org,
	Peter Zijlstra <peterz@infradead.org>,
	Frederic Weisbecker <fweisbec@gmail.com>,
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Hi,

On Thu, May 12, 2011 at 09:48:50AM +0200, Ingo Molnar wrote:
> 1) We already have a specific ABI for this: you can set filters for events via 
>    an event fd.
> 
>    Why not extend that mechanism instead and improve *both* your sandboxing
>    bits and the events code? This new seccomp code has a lot more
>    to do with trace event filters than the minimal old seccomp code ...

Would this require privileges to get the event fd to start with? If so,
I would prefer to avoid that, since using prctl() as shown in the patch
set won't require any privs.

-Kees

-- 
Kees Cook
Ubuntu Security Team