From: cpebenito@tresys.com (Christopher J. PeBenito)
Date: Mon, 07 Jun 2010 09:39:15 -0400
Subject: [refpolicy] kernel_devices.patch
In-Reply-To: <4C0CF2EF.4090909@redhat.com>
References: <4C06BCD3.5020900@redhat.com>
	<1275916842.809.90.camel@gorn.columbia.tresys.com>
	<4C0CF2EF.4090909@redhat.com>
Message-ID: <1275917955.809.93.camel@gorn.columbia.tresys.com>
To: refpolicy@oss.tresys.com
List-Id: refpolicy.oss.tresys.com

On Mon, 2010-06-07 at 09:23 -0400, Daniel J Walsh wrote:
> On 06/07/2010 09:20 AM, Christopher J. PeBenito wrote:
> > On Wed, 2010-06-02 at 16:19 -0400, Daniel J Walsh wrote:
> >> http://people.fedoraproject.org/~dwalsh/SELinux/F14/kernel_devices.patch
> >>
> >> Added default label for /sys so libvirt could relabel to it.
> >
> > I don't understand this.  There should be no files labeled sysfs_t,
> > except for the entries created by the kernel on the fs itself, which get
> > the right label already.
> >
> libvirt currently does the equivalent of
> 
> chcon svirt_t:MCS1 DEVICE
> Run QEMU
> restorecon DEVICE
> 
> If /sys is <<none>> then it does not have a label to change the context 
> back to.  And leaves the context with a label svirt_t:MCS1.  If it later 
> picks an svirt_t:MCS1 for a different image, this /sys device is vulnerable.

I still don't understand.  There are no device nodes in sysfs.

-- 
Chris PeBenito
Tresys Technology, LLC
www.tresys.com | oss.tresys.com