net: orphan frags on stand-alone ptype in dev_queue_xmit_nit
authorWillem de Bruijn <willemb@google.com>
Fri, 22 Sep 2017 23:42:37 +0000 (19:42 -0400)
committerDavid S. Miller <davem@davemloft.net>
Sat, 23 Sep 2017 03:31:29 +0000 (20:31 -0700)
Zerocopy skbs frags are copied when the skb is looped to a local sock.
Commit 1080e512d44d ("net: orphan frags on receive") introduced calls
to skb_orphan_frags to deliver_skb and __netif_receive_skb for this.

With msg_zerocopy, these skbs can also exist in the tx path and thus
loop from dev_queue_xmit_nit. This already calls deliver_skb in its
loop. But it does not orphan before a separate pt_prev->func().

Add the missing skb_orphan_frags_rx.

Changes
  v1->v2: handle skb_orphan_frags_rx failure

Fixes: 1f8b977ab32d ("sock: enable MSG_ZEROCOPY")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/dev.c

index 9a2254f9802f325de65fa569ceeaa5411a31dfcc..588b473194a8a8ce23bde368b2b0350a3317db8b 100644 (file)
@@ -1948,8 +1948,12 @@ again:
                goto again;
        }
 out_unlock:
-       if (pt_prev)
-               pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
+       if (pt_prev) {
+               if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC))
+                       pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
+               else
+                       kfree_skb(skb2);
+       }
        rcu_read_unlock();
 }
 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);