From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Rusty Russell To: Jason Wang , kvm@vger.kernel.org Cc: nab@linux-iscsi.org, linux-scsi@vger.kernel.org, virtualization@lists.linux-foundation.org, Asias He , stable@vger.kernel.org, Jason Wang Subject: Re: [PATCH V2] virtio-scsi: Fix hotcpu_notifier use-after-free with virtscsi_freeze In-Reply-To: <1387258568-11309-1-git-send-email-jasowang@redhat.com> References: <1387258568-11309-1-git-send-email-jasowang@redhat.com> Date: Wed, 15 Jan 2014 10:08:12 +1030 Message-ID: <87fvoqxhgb.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: kvm-owner@vger.kernel.org List-ID: Jason Wang writes: > From: Asias He > > vqs are freed in virtscsi_freeze but the hotcpu_notifier is not > unregistered. We will have a use-after-free usage when the notifier > callback is called after virtscsi_freeze. > > Fixes: 285e71ea6f3583a85e27cb2b9a7d8c35d4c0d558 > ("virtio-scsi: reset virtqueue affinity when doing cpu hotplug") Sorry, I missed this in my earlier sweep (I was only skimming emails during the break). Applied, Rusty. > Cc: stable@vger.kernel.org > Signed-off-by: Asias He > Reviewed-by: Paolo Bonzini > Signed-off-by: Jason Wang > --- > Changes from V1: > - Add "Fixes" line > - CC stable > --- > drivers/scsi/virtio_scsi.c | 15 ++++++++++++++- > 1 file changed, 14 insertions(+), 1 deletion(-) > > diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c > index c3173dc..16bfd50 100644 > --- a/drivers/scsi/virtio_scsi.c > +++ b/drivers/scsi/virtio_scsi.c > @@ -956,6 +956,10 @@ static void virtscsi_remove(struct virtio_device *vdev) > #ifdef CONFIG_PM_SLEEP > static int virtscsi_freeze(struct virtio_device *vdev) > { > + struct Scsi_Host *sh = virtio_scsi_host(vdev); > + struct virtio_scsi *vscsi = shost_priv(sh); > + > + unregister_hotcpu_notifier(&vscsi->nb); > virtscsi_remove_vqs(vdev); > return 0; > } > @@ -964,8 +968,17 @@ static int virtscsi_restore(struct virtio_device *vdev) > { > struct Scsi_Host *sh = virtio_scsi_host(vdev); > struct virtio_scsi *vscsi = shost_priv(sh); > + int err; > + > + err = virtscsi_init(vdev, vscsi); > + if (err) > + return err; > + > + err = register_hotcpu_notifier(&vscsi->nb); > + if (err) > + vdev->config->del_vqs(vdev); > > - return virtscsi_init(vdev, vscsi); > + return err; > } > #endif > > -- > 1.8.3.2