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Date: Sat, 3 Nov 2012 00:22:44 +0000
From: Matthew Garrett <mjg@redhat.com>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Pavel Machek <pavel@ucw.cz>, Chris Friesen <chris.friesen@genband.com>,
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        Josh Boyer <jwboyer@gmail.com>, linux-kernel@vger.kernel.org,
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Subject: Re: [RFC] Second attempt at kernel secure boot support
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On Fri, Nov 02, 2012 at 11:38:23PM +0000, James Bottomley wrote:
> On Fri, 2012-11-02 at 18:04 +0000, Matthew Garrett wrote:
> > A user runs a binary that elevates itself to admin. Absent any flaws in 
> > Windows (cough), that should be all it can do in a Secure Boot world. 
> > But if you can drop a small trusted Linux system in there and use that 
> > to boot a compromised Windows kernel, it can make itself persistent.
> 
> We seem to be talking past each other.  Assume you managed to install a
> Linux boot system on the windows machine.  If the linux boot requires
> present user on first boot (either because the key of the bootloader
> isn't in db or because the MOK database isn't initialised), you still
> don't have a compromise because the loader won't start automatically.

Why would an attacker use one of those Linux systems? There's going to 
be plenty available that don't have that restriction.

-- 
Matthew Garrett | mjg59@srcf.ucam.org
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