| From | Ben Hutchings <> | Date | Mon, 28 Apr 2014 02:11:21 +0100 | Subject | [PATCH 3.2 09/94] vhost: validate vhost_get_vq_desc return value |
| |
3.2.58-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: "Michael S. Tsirkin" <mst@redhat.com>
[ Upstream commit a39ee449f96a2cd44ce056d8a0a112211a9b1a1f ]
vhost fails to validate negative error code from vhost_get_vq_desc causing a crash: we are using -EFAULT which is 0xfffffff2 as vector size, which exceeds the allocated size.
The code in question was introduced in commit 8dd014adfea6f173c1ef6378f7e5e7924866c923 vhost-net: mergeable buffers support
CVE-2014-0055
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> --- drivers/vhost/net.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -319,9 +319,13 @@ static int get_rx_bufs(struct vhost_virt r = -ENOBUFS; goto err; } - d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, + r = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, ARRAY_SIZE(vq->iov) - seg, &out, &in, log, log_num); + if (unlikely(r < 0)) + goto err; + + d = r; if (d == vq->num) { r = 0; goto err;
|