mISDN: Fix skb leak in error cases

If the channel receive function returns an error the skb must be freed.
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/mISDN/socket.c

@@ -209,7 +209,7 @@ mISDN_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 
 	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
 		err = -EFAULT;
-		goto drop;
+		goto done;
 	}
 
 	memcpy(mISDN_HEAD_P(skb), skb->data, MISDN_HEADER_LEN);
@@ -230,19 +230,21 @@ mISDN_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
 		     __func__, mISDN_HEAD_ID(skb));
 
 	err = -ENODEV;
-	if (!_pms(sk)->ch.peer ||
-	    (err = _pms(sk)->ch.recv(_pms(sk)->ch.peer, skb)))
-		goto drop;
-
+	if (!_pms(sk)->ch.peer)
+		goto done;
+	err = _pms(sk)->ch.recv(_pms(sk)->ch.peer, skb);
+	if (err)
+		goto done;
+	else {
+		skb = NULL;
 		err = len;
+	}
 
 done:
+	if (skb)
+		kfree_skb(skb);
 	release_sock(sk);
 	return err;
-
-drop:
-	kfree_skb(skb);
-	goto done;
 }
 
 static int