From mboxrd@z Thu Jan  1 00:00:00 1970
From: George Dunlap <george.dunlap@eu.citrix.com>
Subject: Re: DOMID_XEN and iomem_access_permitted
Date: Wed, 12 May 2010 15:55:57 -0500
Message-ID: <4BEB15DD.7020208@eu.citrix.com>
References: <C810D2A1.1CAF%keir.fraser@eu.citrix.com>
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To: Keir Fraser <Keir.Fraser@eu.citrix.com>
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Keir Fraser wrote:
> Unprivileged domains will be unable to obtain a reference to dom_xen. So
> this bug can only trigger from dom0.
>   
OK -- and DOMID_IO redirects the checks back to current->domain before 
calling iomem_access_permitted() in get_page_from_l1e().  So we don't 
believe a domU should be able to pass a "dummy domain" to 
iomem_access_permitted().  Good to know. :-)

 -George