From: Eric Dumazet <edumazet@google.com>
Date: Fri, 8 Sep 2017 12:44:47 -0700
Subject: tcp: fix a request socket leak
Patch-mainline: v4.14-rc1
Git-commit: 1f3b359f1004bd34b7b0bad70b93e3c7af92a37b
References: bsc#1076830

While the cited commit fixed a possible deadlock, it added a leak
of the request socket, since reqsk_put() must be called if the BPF
filter decided the ACK packet must be dropped.

Fixes: d624d276d1dd ("tcp: fix possible deadlock in TCP stack vs BPF filter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Kubecek <mkubecek@suse.cz>

---
 net/ipv4/tcp_ipv4.c | 6 +++---
 net/ipv6/tcp_ipv6.c | 6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 0d4cdd9e7058..8bbc1ef4dcfd 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1616,9 +1616,9 @@ int tcp_v4_rcv(struct sk_buff *skb)
 		 */
 		sock_hold(sk);
 		refcounted = true;
-		if (tcp_filter(sk, skb))
-			goto discard_and_relse;
-		nsk = tcp_check_req(sk, skb, req, false);
+		nsk = NULL;
+		if (!tcp_filter(sk, skb))
+			nsk = tcp_check_req(sk, skb, req, false);
 		if (!nsk) {
 			reqsk_put(req);
 			goto discard_and_relse;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 608037f83acc..98c4d17a4543 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1445,9 +1445,9 @@ static int tcp_v6_rcv(struct sk_buff *skb)
 		}
 		sock_hold(sk);
 		refcounted = true;
-		if (tcp_filter(sk, skb))
-			goto discard_and_relse;
-		nsk = tcp_check_req(sk, skb, req, false);
+		nsk = NULL;
+		if (!tcp_filter(sk, skb))
+			nsk = tcp_check_req(sk, skb, req, false);
 		if (!nsk) {
 			reqsk_put(req);
 			goto discard_and_relse;
-- 
2.16.2