Message-ID: <4F3DA2BC.7010706@zytor.com>
Date: Thu, 16 Feb 2012 16:43:40 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Will Drewry <wad@chromium.org>
CC: Markus Gutschke <markus@chromium.org>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v8 3/8] seccomp: add system call filtering using BPF
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On 02/16/2012 03:00 PM, Will Drewry wrote:
>
> Without the addition of x32, it is still the intersection of
> is_compat_task()/TS_COMPAT and CONFIG_64BIT for all arches to
> determine if the call is 32-bit or 64-bit, but this will add another
> wrinkle.  Would it make sense to assume that system call namespaces
> may be ever expanding and offer up an unsigned integer value?
>

This is definitely the most general solution.

By the way, although most processes only use one set of system calls, 
there are legitimate reasons for cross-mode tasks, and those probably 
have a high overlap with the ones that would benefit from this kind of 
filtering facility, e.g. pin.

	-hpa

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