From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: BUG: IPv4: Attempt to release TCP socket in state 1
Date: Sun, 17 Mar 2013 12:00:44 -0700
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Cc: Cong Wang <xiyou.wangcong@gmail.com>, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org
To: dormando <dormando@rydia.net>
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On Sun, 2013-03-17 at 09:52 -0700, Eric Dumazet wrote:

> 
> We perform a sock_hold() somewhere while the socket is already dead.

Oh well, thats not exactly that.

When processing ICMP messages we perform a full inet[6] lookup and can
find a LISTEN socket.

Please try the following fix :

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index b7ab868..3d250c6 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -407,7 +407,8 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
 		if (code > NR_ICMP_UNREACH)
 			goto out;
 
-		if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */
+		if (sk->sk_state != TCP_LISTEN &&
+		    code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */
 			tp->mtu_info = info;
 			if (!sock_owned_by_user(sk)) {
 				tcp_v4_mtu_reduced(sk);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 9b64600..c12b3ff 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -388,7 +388,7 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 			dst->ops->redirect(dst, sk, skb);
 	}
 
-	if (type == ICMPV6_PKT_TOOBIG) {
+	if (type == ICMPV6_PKT_TOOBIG && sk->sk_state != TCP_LISTEN) {
 		tp->mtu_info = ntohl(info);
 		if (!sock_owned_by_user(sk))
 			tcp_v6_mtu_reduced(sk);