diff options
author | Stefan Hajnoczi <stefanha@redhat.com> | 2016-08-04 14:52:53 +0100 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2016-08-09 13:42:37 +0300 |
commit | 3fda5d6e580193fa005014355b3a61498f1b3ae0 (patch) | |
tree | 351ecd0bebf5e2e863ad233fe356cf54a08d9ce3 | |
parent | 1b8553c04bf95180eb91be94f089a1e8b38cfd62 (diff) | |
download | linux-3fda5d6e580193fa005014355b3a61498f1b3ae0.tar.bz2 |
vhost/vsock: fix vhost virtio_vsock_pkt use-after-free
Stash the packet length in a local variable before handing over
ownership of the packet to virtio_transport_recv_pkt() or
virtio_transport_free_pkt().
This patch solves the use-after-free since pkt is no longer guaranteed
to be alive.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
-rw-r--r-- | drivers/vhost/vsock.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index 0ddf3a2dbfc4..e3b30ea9ece5 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -307,6 +307,8 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work) vhost_disable_notify(&vsock->dev, vq); for (;;) { + u32 len; + if (!vhost_vsock_more_replies(vsock)) { /* Stop tx until the device processes already * pending replies. Leave tx virtqueue @@ -334,13 +336,15 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work) continue; } + len = pkt->len; + /* Only accept correctly addressed packets */ if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid) virtio_transport_recv_pkt(pkt); else virtio_transport_free_pkt(pkt); - vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len); + vhost_add_used(vq, head, sizeof(pkt->hdr) + len); added = true; } |