tipc: fix RDM/DGRAM connect() regression

[ Upstream commit 0e632089 ]

Fix regression bug introduced in
commit 365ad353 ("tipc: reduce risk of user starvation during link
congestion")

Only signal -EDESTADDRREQ for RDM/DGRAM if we don't have a cached
sockaddr.

Fixes: 365ad353 ("tipc: reduce risk of user starvation during link congestion")
Signed-off-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

net/tipc/socket.c

@@ -1318,7 +1318,7 @@ static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen)
 
 	if (unlikely(!dest)) {
 		dest = &tsk->peer;
-		if (!syn || dest->family != AF_TIPC)
+		if (!syn && dest->family != AF_TIPC)
 			return -EDESTADDRREQ;
 	}