From 429a07b0fde07d5c6a56681fb22947f8cbe5c92c Mon Sep 17 00:00:00 2001
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 10 Mar 2012 09:20:21 +0000
Subject: [PATCH] --- yaml --- r: 288437 b: refs/heads/master c:
 dfd25ffffc132c00070eed64200e8950da5d7e9d h: refs/heads/master i:   288435:
 923b3e682ccf3eb4fd0e50b1e8706b57ee388d02 v: v3

---
 [refs]                      |  2 +-
 trunk/net/ipv4/syncookies.c | 30 ++++++++++++++++--------------
 trunk/net/ipv4/tcp_ipv4.c   | 10 +++++++---
 3 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/[refs] b/[refs]
index efb499aea8c7..eee858832ca9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 4e50391968849860dff1aacde358b4eb14aa5127
+refs/heads/master: dfd25ffffc132c00070eed64200e8950da5d7e9d
diff --git a/trunk/net/ipv4/syncookies.c b/trunk/net/ipv4/syncookies.c
index 51fdbb490437..eab2a7fb15d1 100644
--- a/trunk/net/ipv4/syncookies.c
+++ b/trunk/net/ipv4/syncookies.c
@@ -278,6 +278,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
 	struct rtable *rt;
 	__u8 rcv_wscale;
 	bool ecn_ok = false;
+	struct flowi4 fl4;
 
 	if (!sysctl_tcp_syncookies || !th->ack || th->rst)
 		goto out;
@@ -346,20 +347,16 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
 	 * hasn't changed since we received the original syn, but I see
 	 * no easy way to do this.
 	 */
-	{
-		struct flowi4 fl4;
-
-		flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
-				   RT_SCOPE_UNIVERSE, IPPROTO_TCP,
-				   inet_sk_flowi_flags(sk),
-				   (opt && opt->srr) ? opt->faddr : ireq->rmt_addr,
-				   ireq->loc_addr, th->source, th->dest);
-		security_req_classify_flow(req, flowi4_to_flowi(&fl4));
-		rt = ip_route_output_key(sock_net(sk), &fl4);
-		if (IS_ERR(rt)) {
-			reqsk_free(req);
-			goto out;
-		}
+	flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
+			   RT_SCOPE_UNIVERSE, IPPROTO_TCP,
+			   inet_sk_flowi_flags(sk),
+			   (opt && opt->srr) ? opt->faddr : ireq->rmt_addr,
+			   ireq->loc_addr, th->source, th->dest);
+	security_req_classify_flow(req, flowi4_to_flowi(&fl4));
+	rt = ip_route_output_key(sock_net(sk), &fl4);
+	if (IS_ERR(rt)) {
+		reqsk_free(req);
+		goto out;
 	}
 
 	/* Try to redo what tcp_v4_send_synack did. */
@@ -373,5 +370,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
 	ireq->rcv_wscale  = rcv_wscale;
 
 	ret = get_cookie_sock(sk, skb, req, &rt->dst);
+	/* ip_queue_xmit() depends on our flow being setup
+	 * Normal sockets get it right from inet_csk_route_child_sock()
+	 */
+	if (ret)
+		inet_sk(ret)->cork.fl.u.ip4 = fl4;
 out:	return ret;
 }
diff --git a/trunk/net/ipv4/tcp_ipv4.c b/trunk/net/ipv4/tcp_ipv4.c
index 94d683a61cba..fd54c5f8a255 100644
--- a/trunk/net/ipv4/tcp_ipv4.c
+++ b/trunk/net/ipv4/tcp_ipv4.c
@@ -1466,9 +1466,13 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 		inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
 	newinet->inet_id = newtp->write_seq ^ jiffies;
 
-	if (!dst && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL)
-		goto put_and_exit;
-
+	if (!dst) {
+		dst = inet_csk_route_child_sock(sk, newsk, req);
+		if (!dst)
+			goto put_and_exit;
+	} else {
+		/* syncookie case : see end of cookie_v4_check() */
+	}
 	sk_setup_caps(newsk, dst);
 
 	tcp_mtup_init(newsk);