tipc: ignore requests when the connection state is not CONNECTED

BugLink: http://bugs.launchpad.net/bugs/1698817

[ Upstream commit 4c887aa6 ]

In tipc_conn_sendmsg(), we first queue the request to the outqueue
followed by the connection state check. If the connection is not
connected, we should not queue this message.

In this commit, we reject the messages if the connection state is
not CF_CONNECTED.
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Tested-by: John Thompson <thompa.atl@gmail.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

net/tipc/server.c

@@ -452,6 +452,11 @@ int tipc_conn_sendmsg(struct tipc_server *s, int conid,
 	if (!con)
 		return -EINVAL;
 
+	if (!test_bit(CF_CONNECTED, &con->flags)) {
+		conn_put(con);
+		return 0;
+	}
+
 	e = tipc_alloc_entry(data, len);
 	if (!e) {
 		conn_put(con);
@@ -465,12 +470,8 @@ int tipc_conn_sendmsg(struct tipc_server *s, int conid,
 	list_add_tail(&e->list, &con->outqueue);
 	spin_unlock_bh(&con->outqueue_lock);
 
-	if (test_bit(CF_CONNECTED, &con->flags)) {
-		if (!queue_work(s->send_wq, &con->swork))
-			conn_put(con);
-	} else {
+	if (!queue_work(s->send_wq, &con->swork))
 		conn_put(con);
-	}
 	return 0;
 }
 
@@ -494,7 +495,7 @@ static void tipc_send_to_sock(struct tipc_conn *con)
 	int ret;
 
 	spin_lock_bh(&con->outqueue_lock);
-	while (1) {
+	while (test_bit(CF_CONNECTED, &con->flags)) {
 		e = list_entry(con->outqueue.next, struct outqueue_entry,
 			       list);
 		if ((struct list_head *) e == &con->outqueue)