openvswitch: Fix double reporting of drops in dropwatch

[ Upstream commit 1100248a5c5ccd57059eb8d02ec077e839a23826 ]

Frames sent to userspace can be reported as dropped in
ovs_dp_process_packet, however, if they are dropped in the netlink code
then netlink_attachskb will report the same frame as dropped.

This patch checks for error codes which indicate that the frame has
already been freed.

Signed-off-by: Mike Pattrick <mkp@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2109946
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 3248cf04d0b361bd6d87ca0ffb526ccdea7c121c..42616aca0ce44531892ef2b86e50c16fa5e8ad80 100644 (file)
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -276,10 +276,17 @@ void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
                upcall.portid = ovs_vport_find_upcall_portid(p, skb);
                upcall.mru = OVS_CB(skb)->mru;
                error = ovs_dp_upcall(dp, skb, key, &upcall, 0);
-               if (unlikely(error))
-                       kfree_skb(skb);
-               else
+               switch (error) {
+               case 0:
+               case -EAGAIN:
+               case -ERESTARTSYS:
+               case -EINTR:
                        consume_skb(skb);
+                       break;
+               default:
+                       kfree_skb(skb);
+                       break;
+               }
                stats_counter = &stats->n_missed;
                goto out;
        }