bpf: Remove duplicate tcp_filter hook in ipv6

Chenbo Feng · davem330 · commit 384abed1fe49 · 2017-06-10T16:08:02.000-04:00
There are two tcp_filter hooks in tcp_ipv6 ingress path currently.
One is at tcp_v6_rcv and another is in tcp_v6_do_rcv. It seems the
tcp_filter() call inside tcp_v6_do_rcv is redundent and some packet
will be filtered twice in this situation. This will cause trouble
when using eBPF filters to account traffic data.

Signed-off-by: Chenbo Feng &lt;fengc@google.com&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
@@ -1249,9 +1249,6 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 	if (skb->protocol == htons(ETH_P_IP))
 		return tcp_v4_do_rcv(sk, skb);
 
-	if (tcp_filter(sk, skb))
-		goto discard;
-
 	/*
 	 *	socket locking is here for SMP purposes as backlog rcv
 	 *	is currently called with bh processing disabled.
