From: Chenbo Feng <fengc@google.com>
Date: Fri, 9 Jun 2017 19:17:37 +0000 (-0700)
Subject: bpf: Remove duplicate tcp_filter hook in ipv6
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=384abed1fe49cd3f473d61d3297a6fec5e420699;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

bpf: Remove duplicate tcp_filter hook in ipv6

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

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 0840543fc245..84ad50218255 100644
--- 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.