From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39716) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4Z4h-0003Ku-4u for qemu-devel@nongnu.org; Tue, 08 Jul 2014 13:21:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X4Z4N-0007g9-Kb for qemu-devel@nongnu.org; Tue, 08 Jul 2014 13:21:03 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:43754) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4Z4N-0007fV-0B for qemu-devel@nongnu.org; Tue, 08 Jul 2014 13:20:43 -0400 Received: from /spool/local by e9.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 8 Jul 2014 13:20:42 -0400 From: Michael Roth Date: Tue, 8 Jul 2014 12:17:09 -0500 Message-Id: <1404839947-1086-39-git-send-email-mdroth@linux.vnet.ibm.com> In-Reply-To: <1404839947-1086-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1404839947-1086-1-git-send-email-mdroth@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH 038/156] virtio: out-of-bounds buffer write on invalid state load List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org From: "Michael S. Tsirkin" CVE-2013-4151 QEMU 1.0 out-of-bounds buffer write in virtio_load@hw/virtio/virtio.c So we have this code since way back when: num = qemu_get_be32(f); for (i = 0; i < num; i++) { vdev->vq[i].vring.num = qemu_get_be32(f); array of vqs has size VIRTIO_PCI_QUEUE_MAX, so on invalid input this will write beyond end of buffer. Signed-off-by: Michael S. Tsirkin Reviewed-by: Michael Roth Signed-off-by: Juan Quintela (cherry picked from commit cc45995294b92d95319b4782750a3580cabdbc0c) Signed-off-by: Michael Roth --- hw/virtio/virtio.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 965b2c0..8dc3cb3 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -888,7 +888,8 @@ int virtio_set_features(VirtIODevice *vdev, uint32_t val) int virtio_load(VirtIODevice *vdev, QEMUFile *f) { - int num, i, ret; + int i, ret; + uint32_t num; uint32_t features; uint32_t supported_features; BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); @@ -916,6 +917,11 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f) num = qemu_get_be32(f); + if (num > VIRTIO_PCI_QUEUE_MAX) { + error_report("Invalid number of PCI queues: 0x%x", num); + return -1; + } + for (i = 0; i < num; i++) { vdev->vq[i].vring.num = qemu_get_be32(f); if (k->has_variable_vring_alignment) { -- 1.9.1