[NET]: Fix sk->sk_filter field access

Function sk_filter() is called from tcp_v{4,6}_rcv() functions with arg
needlock = 0, while socket is not locked at that moment. In order to avoid
this and similar issues in the future, use rcu for sk->sk_filter field read
protection.

Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Kirill Korotaev <dev@openvz.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 2b18918f3011..2546fc9f0a78 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1075,7 +1075,7 @@ 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 (sk_filter(sk, skb, 0))
+        if (sk_filter(sk, skb))
                 goto discard;
 
         /*
@@ -1232,7 +1232,7 @@ process:
         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
                 goto discard_and_relse;
 
-        if (sk_filter(sk, skb, 0))
+        if (sk_filter(sk, skb))
                 goto discard_and_relse;
 
         skb->dev = NULL;