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Date: Thu, 28 Feb 2013 19:30:23 +0000
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Chris Friesen <chris.friesen@genband.com>
Cc: Florian Weimer <fw@deneb.enyo.de>, Greg KH <gregkh@linuxfoundation.org>,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [GIT PULL] Load keys from signed PE binaries
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On Thu, Feb 28, 2013 at 09:43:10AM -0600, Chris Friesen wrote:
> On 02/28/2013 01:57 AM, Florian Weimer wrote:
> 
> >In any case, there's another reading of the UEFI Secure Boot
> >requirements: you may run any code you wish after calling
> >ExitBootServices().  That could be an unsigned, traditional GRUB.  But
> >this will not generally address the issue of dual-booting Windows 8 in
> >such a way that Windows sees that the device has enabled Microsoft
> >Secure Boot.
> 
> Would it be possible to have a signed bootloader that allows booting
> Win8 from within the secure environment, or it could exit the secure
> environment and run unsigned grub?

What would stop the unsigned grub from installing a firmware hook that 
lies about whether or not Secure Boot is enabled, and then booting 
Windows?

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