[PATCH stable v2 3/3] virtio_net: don't leak memory or block when too many frags

Michael S. Tsirkin
2013-12-26T13:29:09Z

We leak an skb when there are too many frags,
we also stop processing the packet in the middle,
the result is almost sure to be loss of networking.

Reported-by: Michael Dalton <mwdalton@google.com>
Acked-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
drivers/net/virtio_net.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index c0ed6d5..b8665588 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -344,7 +344,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
if (i >= MAX_SKB_FRAGS) {
pr_debug("%s: packet too long\n", skb->dev->name);
skb->dev->stats.rx_length_errors++;
- return NULL;
+ goto err_frags;
}
page = virtqueue_get_buf(rq->vq, &len);
if (!page) {
@@ -365,6 +365,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
err_skb:
give_pages(rq, page);
while (--num_buf) {
+err_frags:
buf = virtqueue_get_buf(rq->vq, &len);
if (unlikely(!buf)) {
pr_debug("%s: rx error: %d buffers missing\n",
--
MST