qemu/0305-virtio-out-of-bounds-buffer-write-on-invalid-state-l.patch
2014-05-11 18:43:54 -04:00

53 lines
1.6 KiB
Diff

From aa7a505a6ddfc7ae215adcbf49f9e135b8471643 Mon Sep 17 00:00:00 2001
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Thu, 3 Apr 2014 19:51:14 +0300
Subject: [PATCH] virtio: out-of-bounds buffer write on invalid state load
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 <mst@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
(cherry picked from commit cc45995294b92d95319b4782750a3580cabdbc0c)
---
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) {