From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH] virtio-pci: fix use after free
Date: Tue, 08 Nov 2011 20:49:27 +1030
Message-ID: <87y5vqrk5s.fsf@rustcorp.com.au>
References: <20111107163703.GA10358@redhat.com>
	<20111108054616.GC2068@amit-x200.redhat.com>
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To: Amit Shah <amit.shah@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>
Cc: stable@kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org
List-Id: virtualization@lists.linuxfoundation.org

On Tue, 8 Nov 2011 11:16:16 +0530, Amit Shah <amit.shah@redhat.com> wrote:
> On (Mon) 07 Nov 2011 [18:37:05], Michael S. Tsirkin wrote:
> > Commit 31a3ddda166cda86d2b5111e09ba4bda5239fae6 introduced
> > a use after free in virtio-pci. The main issue is
> > that the release method signals removal of the virtio device,
> > while remove signals removal of the pci device.
> > 
> > For example, on driver removal or hot-unplug,
> > virtio_pci_release_dev is called before virtio_pci_remove.
> > We then might get a crash as virtio_pci_remove tries to use the
> > device freed by virtio_pci_release_dev.
> > 
> > We allocate/free all resources together with the
> > pci device, so we can leave the release method empty.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> 
> Acked-by: Amit Shah <amit.shah@redhat.com>
> 
> (note: Adding CC: stable@kernel.org to the commit log is the way
> patches get automatically pulled from upstream when committed; CC'ing
> stable on submissions won't help with that.)

Yeah, I fixed it though.

Cheers,
Rusty.