[PATCH 4.9 21/72] rds: tcp: use sock_create_lite() to create the accept socket

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Sowmini Varadhan <sowmini.varadhan@xxxxxxxxxx>

commit 0933a578cd55b02dc80f219dc8f2efb17ec61c9a upstream.

There are two problems with calling sock_create_kern() from
rds_tcp_accept_one()
1. it sets up a new_sock->sk that is wasteful, because this ->sk
   is going to get replaced by inet_accept() in the subsequent ->accept()
2. The new_sock->sk is a leaked reference in sock_graft() which
   expects to find a null parent->sk

Avoid these problems by calling sock_create_lite().

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@xxxxxxxxxx>
Acked-by: Santosh Shilimkar <santosh.shilimkar@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/rds/tcp_listen.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/rds/tcp_listen.c
+++ b/net/rds/tcp_listen.c
@@ -129,7 +129,7 @@ int rds_tcp_accept_one(struct socket *so
 	if (!sock) /* module unload or netns delete in progress */
 		return -ENETUNREACH;
 
-	ret = sock_create_kern(sock_net(sock->sk), sock->sk->sk_family,
+	ret = sock_create_lite(sock->sk->sk_family,
 			       sock->sk->sk_type, sock->sk->sk_protocol,
 			       &new_sock);
 	if (ret)