From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH net 2/2] vhost: do not try to access device IOTLB when not initialized Date: Tue, 23 Jan 2018 17:58:10 +0200 Message-ID: <20180123175804-mutt-send-email-mst@kernel.org> References: <1516699646-7321-1-git-send-email-jasowang@redhat.com> <1516699646-7321-2-git-send-email-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1516699646-7321-2-git-send-email-jasowang@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Jason Wang Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org On Tue, Jan 23, 2018 at 05:27:26PM +0800, Jason Wang wrote: > The code will try to access dev->iotlb when processing > VHOST_IOTLB_INVALIDATE even if it was not initialized which may lead > to NULL pointer dereference. Fixes this by check dev->iotlb before. > > Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API") > Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin > --- > drivers/vhost/vhost.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index 549771a..5727b18 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -1015,6 +1015,10 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev, > vhost_iotlb_notify_vq(dev, msg); > break; > case VHOST_IOTLB_INVALIDATE: > + if (!dev->iotlb) { > + ret = -EFAULT; > + break; > + } > vhost_vq_meta_reset(dev); > vhost_del_umem_range(dev->iotlb, msg->iova, > msg->iova + msg->size - 1); > -- > 2.7.4