tcp: md5: increment sk_drops on syn_recv state

TCP MD5 mismatches do increment sk_drops counter in all states but
SYN_RECV.

This is very unlikely to happen in the real world, but worth adding
to help diagnostics.

We increase the parent (listener) sk_drops.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 32b048e..436d978 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1602,6 +1602,7 @@ process:
 
                sk = req->rsk_listener;
                if (unlikely(tcp_v4_inbound_md5_hash(sk, skb))) {
+                       sk_drops_add(sk, skb);
                        reqsk_put(req);
                        goto discard_it;
                }

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index e0f4643..ac0ed7b 100644 (file)
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1409,6 +1409,7 @@ process:
                sk = req->rsk_listener;
                tcp_v6_fill_cb(skb, hdr, th);
                if (tcp_v6_inbound_md5_hash(sk, skb)) {
+                       sk_drops_add(sk, skb);
                        reqsk_put(req);
                        goto discard_it;
                }