tipc: use limited socket backlog

Make tipc adapt to the limited socket backlog change.

Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: NZhu Yi <yi.zhu@intel.com>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NAllan Stephens <allan.stephens@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/tipc/socket.c

@@ -1322,8 +1322,10 @@ static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf)
 	if (!sock_owned_by_user(sk)) {
 		res = filter_rcv(sk, buf);
 	} else {
-		sk_add_backlog(sk, buf);
-		res = TIPC_OK;
+		if (sk_add_backlog_limited(sk, buf))
+			res = TIPC_ERR_OVERLOAD;
+		else
+			res = TIPC_OK;
 	}
 	bh_unlock_sock(sk);