netrom: copy_datagram_iovec can fail

Check for an error from this and if so bail properly.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
index 06592d8..1b9024e 100644
--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -1169,7 +1169,12 @@
 		msg->msg_flags |= MSG_TRUNC;
 	}
 
-	skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
+	er = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
+	if (er < 0) {
+		skb_free_datagram(sk, skb);
+		release_sock(sk);
+		return er;
+	}
 
 	if (sax != NULL) {
 		sax->sax25_family = AF_NETROM;