tipc: Fix missing connection request handling
authorParthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Wed, 26 Apr 2017 08:05:00 +0000 (10:05 +0200)
committerDavid S. Miller <davem@davemloft.net>
Fri, 28 Apr 2017 16:20:42 +0000 (12:20 -0400)
In filter_connect, we use waitqueue_active() to check for any
connections to wakeup. But waitqueue_active() is missing memory
barriers while accessing the critical sections, leading to
inconsistent results.

In this commit, we replace this with an SMP safe wq_has_sleeper()
using the generic socket callback sk_data_ready().

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/tipc/socket.c

index 566906795c8c7696126cc8ad9d56e65ed4168497..3b8df510a80c3a77cb5dc3a87728b9c378cdf3ca 100644 (file)
@@ -1581,8 +1581,7 @@ static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb)
                        return true;
 
                /* If empty 'ACK-' message, wake up sleeping connect() */
-               if (waitqueue_active(sk_sleep(sk)))
-                       wake_up_interruptible(sk_sleep(sk));
+               sk->sk_data_ready(sk);
 
                /* 'ACK-' message is neither accepted nor rejected: */
                msg_set_dest_droppable(hdr, 1);