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Date: Wed, 13 Feb 2013 17:08:55 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Matthew Garrett <matthew.garrett@nebula.com>
CC: Casey Schaufler <casey@schaufler-ca.com>, Borislav Petkov <bp@alien8.de>,
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Subject: Re: [PATCH] x86: Lock down MSR writing in secure boot
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On 02/13/2013 05:04 PM, Matthew Garrett wrote:
> On Wed, 2013-02-13 at 16:44 -0800, Casey Schaufler wrote:
> 
>> If you want that sort of granularity throw yourself on the SELinux
>> bandwagon. Fine grained capabilities are insane and unmanageable
>> and will only lead to tears. Security is despised because of the
>> notion that making systems impossible to use is a good thing.
> 
> SELinux is completely unusable for this specific case.
> 

Well, for at least things with device nodes (/dev/mem, /dev/msr and so
on) it should be possible, no?  ioperm() and iopl() are another matter.

	-hpa