tipc: fix memory leak in tipc_accept_from_sock()

BugLink: http://bugs.launchpad.net/bugs/1745047

[ Upstream commit a7d5f107 ]

When the function tipc_accept_from_sock() fails to create an instance of
struct tipc_subscriber it omits to free the already created instance of
struct tipc_conn instance before it returns.

We fix that with this commit.
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

net/tipc/server.c

@@ -311,6 +311,7 @@ static int tipc_accept_from_sock(struct tipc_conn *con)
 	newcon->usr_data = s->tipc_conn_new(newcon->conid);
 	if (!newcon->usr_data) {
 		sock_release(newsock);
+		conn_put(newcon);
 		return -ENOMEM;
 	}