From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42652) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XtyGq-0002eG-52 for qemu-devel@nongnu.org; Thu, 27 Nov 2014 07:34:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XtyGl-0007B0-Os for qemu-devel@nongnu.org; Thu, 27 Nov 2014 07:34:04 -0500 Date: Thu, 27 Nov 2014 14:33:41 +0200 From: "Michael S. Tsirkin" Message-ID: <20141127123341.GC13476@redhat.com> References: <1417082643-23907-1-git-send-email-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1417082643-23907-1-git-send-email-jasowang@redhat.com> Subject: Re: [Qemu-devel] [2.2 PATCH V2] virtio-net: fix unmap leak List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang Cc: peter.maydell@linaro.org, famz@redhat.com, Stefano Stabellini , qemu-stable@nongnu.org, qemu-devel@nongnu.org, aliguori@amazon.com On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > virtio_net_handle_ctrl() and other functions that process control vq > request call iov_discard_front() which will shorten the iov. This will > lead unmapping in virtqueue_push() leaks mapping. > > Fixes this by keeping the original iov untouched and using a temp variable > in those functions. > > Cc: Wen Congyang > Cc: Stefano Stabellini > Cc: qemu-stable@nongnu.org > Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin Peter, can you pick this up or do you want a pull request? > --- > Changes from V1: > - Use g_memdup() to simplify codes > --- > hw/net/virtio-net.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 9b88775..e574bd4 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -798,7 +798,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > virtio_net_ctrl_ack status = VIRTIO_NET_ERR; > VirtQueueElement elem; > size_t s; > - struct iovec *iov; > + struct iovec *iov, *iov2; > unsigned int iov_cnt; > > while (virtqueue_pop(vq, &elem)) { > @@ -808,8 +808,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > exit(1); > } > > - iov = elem.out_sg; > iov_cnt = elem.out_num; > + iov2 = iov = g_memdup(elem.out_sg, sizeof(struct iovec) * elem.out_num); > s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl)); > iov_discard_front(&iov, &iov_cnt, sizeof(ctrl)); > if (s != sizeof(ctrl)) { > @@ -833,6 +833,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > > virtqueue_push(vq, &elem, sizeof(status)); > virtio_notify(vdev, vq); > + g_free(iov2); > } > } > > -- > 1.9.1