netfilter: conntrack: don't increment invalid counter on NF_REPEAT

The packet isn't invalid, REPEAT means we're trying again after cleaning
out a stale connection, e.g. via tcp tracker.

This caused increases of invalid stat counter in a test case involving
frequent connection reuse, even though no packet is actually invalid.

Fixes: 56a62e2218f5 ("netfilter: conntrack: fix NF_REPEAT handling")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 894a325..d6aa5b4 100644 (file)
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -1924,15 +1924,17 @@ repeat:
                pr_debug("nf_conntrack_in: Can't track with proto module\n");
                nf_ct_put(ct);
                skb->_nfct = 0;
-               NF_CT_STAT_INC_ATOMIC(state->net, invalid);
-               if (ret == -NF_DROP)
-                       NF_CT_STAT_INC_ATOMIC(state->net, drop);
                /* Special case: TCP tracker reports an attempt to reopen a
                 * closed/aborted connection. We have to go back and create a
                 * fresh conntrack.
                 */
                if (ret == -NF_REPEAT)
                        goto repeat;
+
+               NF_CT_STAT_INC_ATOMIC(state->net, invalid);
+               if (ret == -NF_DROP)
+                       NF_CT_STAT_INC_ATOMIC(state->net, drop);
+
                ret = -ret;
                goto out;
        }