tipc: fix wrong connect() return code

The current 'tipc_wait_for_connect()' function does a wait-loop for the
condition 'sk->sk_state != TIPC_CONNECTING' to conclude if the socket
connecting has done. However, when the condition is met, it returns '0'
even in the case the connecting is actually failed, the socket state is
set to 'TIPC_DISCONNECTING' (e.g. when the server socket has closed..).
This results in a wrong return code for the 'connect()' call from user,
making it believe that the connection is established and go ahead with
building, sending a message, etc. but finally failed e.g. '-EPIPE'.

This commit fixes the issue by changing the wait condition to the
'tipc_sk_connected(sk)', so the function will return '0' only when the
connection is really established. Otherwise, either the socket 'sk_err'
if any or '-ETIMEDOUT'/'-EINTR' will be returned correspondingly.
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/tipc/socket.c

@@ -2443,8 +2443,8 @@ static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
 			return sock_intr_errno(*timeo_p);
 
 		add_wait_queue(sk_sleep(sk), &wait);
-		done = sk_wait_event(sk, timeo_p,
-				     sk->sk_state != TIPC_CONNECTING, &wait);
+		done = sk_wait_event(sk, timeo_p, tipc_sk_connected(sk),
+				     &wait);
 		remove_wait_queue(sk_sleep(sk), &wait);
 	} while (!done);
 	return 0;