From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 9 Mar 2010 05:55:56 +0000 (+0000)
Subject: tcp: Fix tcp_v4_rcv()
X-Git-Tag: firefly_0821_release~9833^2~2199^2~266
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=bb134d5d9580fc7b945e3bca3c4b263947022966;p=firefly-linux-kernel-4.4.55.git

tcp: Fix tcp_v4_rcv()

Commit d218d111 (tcp: Generalized TTL Security Mechanism) added a bug
for TIMEWAIT sockets. We should not test min_ttl for TW sockets.

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.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 8d51d39ad1bb..70df40980a87 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1651,15 +1651,15 @@ int tcp_v4_rcv(struct sk_buff *skb)
 	if (!sk)
 		goto no_tcp_socket;
 
+process:
+	if (sk->sk_state == TCP_TIME_WAIT)
+		goto do_time_wait;
+
 	if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) {
 		NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
 		goto discard_and_relse;
 	}
 
-process:
-	if (sk->sk_state == TCP_TIME_WAIT)
-		goto do_time_wait;
-
 	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
 		goto discard_and_relse;
 	nf_reset(skb);