[net] tipc: fix wrong connect() return code

[net] tipc: fix wrong connect() return code

[Tuong Lien]

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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
---
 net/tipc/socket.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 6ebd809ef207..f9b4fb92c0b1 100644
--- a/net/tipc/socket.c
+++ b/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;
-- 
2.13.7

Re: [net] tipc: fix wrong connect() return code

[David Miller]

From: Tuong Lien <tuong.t.lien@dektech.com.au>
Date: Wed,  8 Jan 2020 09:19:00 +0700

> 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: Ying Xue <ying.xue@windriver.com>
> Acked-by: Jon Maloy <jon.maloy@ericsson.com>
> Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>

Applied.