virtio_net: Fix out of bounds access of sq

When XDP is disabled, curr_queue_pairs + smp_processor_id() can be
larger than max_queue_pairs.
There is no guarantee that we have enough XDP send queues dedicated for
each cpu when XDP is disabled, so do not count drops on sq in that case.

Fixes: 5b8f3c8d30 ("virtio_net: Add XDP related stats")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Toshiaki Makita 2019-01-29 09:45:56 +09:00 committed by David S. Miller
parent 188313c137
commit 1667c08a9d
1 changed files with 7 additions and 10 deletions

View File

@ -491,20 +491,17 @@ static int virtnet_xdp_xmit(struct net_device *dev,
int ret, err;
int i;
sq = virtnet_xdp_sq(vi);
if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
ret = -EINVAL;
drops = n;
goto out;
}
/* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this
* indicate XDP resources have been successfully allocated.
*/
xdp_prog = rcu_dereference(rq->xdp_prog);
if (!xdp_prog) {
ret = -ENXIO;
if (!xdp_prog)
return -ENXIO;
sq = virtnet_xdp_sq(vi);
if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) {
ret = -EINVAL;
drops = n;
goto out;
}