[PATCH v1 net] af_unix: Fix memleak of newsk in unix_stream_connect().

[Kuniyuki Iwashima <kuniyu@google.com>]

When prepare_peercred() fails in unix_stream_connect(),
unix_release_sock() is not called for newsk, and the memory
is leaked.

Let's move prepare_peercred() before unix_create1().

Fixes: fd0a109a0f6b ("net, pidfs: prepare for handing out pidfds for reaped sk->sk_peer_pid")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
---
 net/unix/af_unix.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index d0511225799b..f6d56e70c7a2 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1650,10 +1650,9 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr_unsized *uad
 
 	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
 
-	/* First of all allocate resources.
-	 * If we will make it after state is locked,
-	 * we will have to recheck all again in any case.
-	 */
+	err = prepare_peercred(&peercred);
+	if (err)
+		goto out;
 
 	/* create new sock for complete connection */
 	newsk = unix_create1(net, NULL, 0, sock->type);
@@ -1662,10 +1661,6 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr_unsized *uad
 		goto out;
 	}
 
-	err = prepare_peercred(&peercred);
-	if (err)
-		goto out;
-
 	/* Allocate skb for sending to listening sock */
 	skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL);
 	if (!skb) {
-- 
2.53.0.rc2.204.g2597b5adb4-goog