virtio-net: correctly check num_buf during err path

If we successfully linearize the packet, num_buf will be set to zero
which may confuse error handling path which assumes num_buf is at
least 1 and this can lead the code tries to pop the descriptor of next
buffer. Fixing this by checking num_buf against 1 before decreasing.

Fixes: 4941d472bf ("virtio-net: do not reset during XDP set")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jason Wang 2018-05-22 11:44:30 +08:00 committed by David S. Miller
parent 5d458a13dd
commit 850e088d5b

View File

@ -875,7 +875,7 @@ err_xdp:
rcu_read_unlock();
err_skb:
put_page(page);
while (--num_buf) {
while (num_buf-- > 1) {
buf = virtqueue_get_buf(rq->vq, &len);
if (unlikely(!buf)) {
pr_debug("%s: rx error: %d buffers missing\n",