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Date: Tue, 4 Sep 2012 17:13:43 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org,
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Subject: Re: [PATCH 05/11] asus-wmi: Restrict debugfs interface
Message-ID: <20120904161343.GB22961@srcf.ucam.org>
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On Tue, Sep 04, 2012 at 05:12:05PM +0100, Alan Cox wrote:
> On Tue,  4 Sep 2012 11:55:11 -0400
> Matthew Garrett <mjg@redhat.com> wrote:
> 
> > We have no way of validating what all of the Asus WMI methods do on a
> > given machine, and there's a risk that some will allow hardware state to
> > be manipulated in such a way that arbitrary code can be executed in the
> > kernel. Add a capability check to prevent that.
> 
> This is true of any firmware method on any device Why pick on ASUS. Have
> you run this through ASUS and discussed it with them. It seems highly
> inappropriate to cripple a specific vendors feature set without
> discussion and an Ack from the vendor concerned.

Because asus-wmi is the only driver that has a debugfs interface that 
lets you run arbitrary WMI methods.

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