Message-ID: <5086BB94.3040208@zytor.com>
Date: Tue, 23 Oct 2012 08:45:24 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Kees Cook <keescook@chromium.org>
CC: Lucas De Marchi <lucas.demarchi@profusion.mobi>,
        Rusty Russell <rusty@rustcorp.com.au>, mtk.manpages@gmail.com,
        linux-kernel@vger.kernel.org, jonathon@jonmasters.org
Subject: Re: [PATCH 1/4] module: add syscall to load module from fd
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On 10/23/2012 08:42 AM, Kees Cook wrote:
>
> Hm, yeah, userspace mangling of a module plus signing would fail.
> Seems like mangling and signing aren't compatible. Doing it in
> kernel-space (as now written for finit_module) solves that, but it
> means that now compression isn't possible if you need both signing and
> mangling.
>
> I'm not a user of signing, compression, or mangling, so I'm probably a
> bit unimaginative here. It seems like the case for needing all three
> is pretty uncommon. (e.g. if you're doing compression, you're probably
> building embedded images, which means you're unlikely to need
> --force.)
>

In particular, mangling and signing aren't compatible... however, 
signing and compression should be just fine (sign before compression).

	-hpa


-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

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