diff options
-rw-r--r-- | net/openvswitch/conntrack.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index 6a2507f24b0f..1829adb23505 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -361,10 +361,38 @@ ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone, u16 proto, const struct sk_buff *skb) { struct nf_conntrack_tuple tuple; + struct nf_conntrack_expect *exp; if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple)) return NULL; - return __nf_ct_expect_find(net, zone, &tuple); + + exp = __nf_ct_expect_find(net, zone, &tuple); + if (exp) { + struct nf_conntrack_tuple_hash *h; + + /* Delete existing conntrack entry, if it clashes with the + * expectation. This can happen since conntrack ALGs do not + * check for clashes between (new) expectations and existing + * conntrack entries. nf_conntrack_in() will check the + * expectations only if a conntrack entry can not be found, + * which can lead to OVS finding the expectation (here) in the + * init direction, but which will not be removed by the + * nf_conntrack_in() call, if a matching conntrack entry is + * found instead. In this case all init direction packets + * would be reported as new related packets, while reply + * direction packets would be reported as un-related + * established packets. + */ + h = nf_conntrack_find_get(net, zone, &tuple); + if (h) { + struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); + + nf_ct_delete(ct, 0, 0); + nf_conntrack_put(&ct->ct_general); + } + } + + return exp; } /* Determine whether skb->nfct is equal to the result of conntrack lookup. */ |