From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41755) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WUd12-0000Tt-0o for qemu-devel@nongnu.org; Mon, 31 Mar 2014 10:16:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WUd0u-0000fj-H2 for qemu-devel@nongnu.org; Mon, 31 Mar 2014 10:16:43 -0400 Date: Mon, 31 Mar 2014 17:16:58 +0300 From: "Michael S. Tsirkin" Message-ID: <1396275242-10810-17-git-send-email-mst@redhat.com> References: <1396275242-10810-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1396275242-10810-1-git-send-email-mst@redhat.com> Subject: [Qemu-devel] [PATCH v4 16/30] virtio: avoid buffer overrun on incoming migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, dgilbert@redhat.com, Anthony Liguori , mdroth@linux.vnet.ibm.com From: Michael Roth CVE-2013-6399 vdev->queue_sel is read from the wire, and later used in the emulation code as an index into vdev->vq[]. If the value of vdev->queue_sel exceeds the length of vdev->vq[], currently allocated to be VIRTIO_PCI_QUEUE_MAX elements, subsequent PIO operations such as VIRTIO_PCI_QUEUE_PFN can be used to overrun the buffer with arbitrary data originating from the source. Fix this by failing migration if the value from the wire exceeds VIRTIO_PCI_QUEUE_MAX. Signed-off-by: Michael Roth Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 9008430..bcbfbb2 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -907,6 +907,9 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f) qemu_get_8s(f, &vdev->status); qemu_get_8s(f, &vdev->isr); qemu_get_be16s(f, &vdev->queue_sel); + if (vdev->queue_sel >= VIRTIO_PCI_QUEUE_MAX) { + return -1; + } qemu_get_be32s(f, &features); if (virtio_set_features(vdev, features) < 0) { -- MST