Message-ID: <51490B5F.7070909@zytor.com>
Date: Tue, 19 Mar 2013 18:05:35 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Matthew Garrett <matthew.garrett@nebula.com>
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Subject: Re: [PATCH 01/12] Security: Add CAP_COMPROMISE_KERNEL
References: <1363642353-30749-1-git-send-email-matthew.garrett@nebula.com> <51490ABD.3050205@zytor.com>
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On 03/19/2013 06:02 PM, H. Peter Anvin wrote:
> 
> Looking at it in detail, EVERYTHING in CAP_SYS_RAWIO has the possibility
> of compromising the kernel, because they let device drivers be bypassed,
> which means arbitrary DMA, which means you have everything.
> 

Well, *unless* you have an iommu that you *actually know* is protecting you.

	-hpa


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

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