From d1ada486bbdecd785762a192eae716a3484d4f16 Mon Sep 17 00:00:00 2001 From: Michael S. Tsirkin Date: Wed, 14 May 2014 08:07:52 +0200 Subject: [PATCH 05/30] virtio: avoid buffer overrun on incoming migration RH-Author: Michael S. Tsirkin Message-id: <1400054498-4366-10-git-send-email-mst@redhat.com> Patchwork-id: 58843 O-Subject: [PATCH qemu-kvm RHEL7.0] virtio: avoid buffer overrun on incoming migration Bugzilla: 1095737 RH-Acked-by: Dr. David Alan Gilbert (git) RH-Acked-by: Xiao Wang RH-Acked-by: Amos Kong 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 Reviewed-by: Peter Maydell Signed-off-by: Juan Quintela (cherry picked from commit 4b53c2c72cb5541cf394033b528a6fe2a86c0ac1) Tested: lightly on developer's box Brew build: http://brewweb.devel.redhat.com/brew/taskinfo?taskID=7450401 Bugzilla:1095737 --- hw/virtio/virtio.c | 3 +++ 1 file changed, 3 insertions(+) Signed-off-by: Miroslav Rezanina --- hw/virtio/virtio.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 070d64e..9600a12 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -867,6 +867,9 @@ 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) { -- 1.7.1