netrom: Fix nr_getname() leak

nr_getname() can leak kernel memory to user.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/netrom/af_netrom.c

@@ -847,6 +847,7 @@ static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
 		sax->fsa_ax25.sax25_family = AF_NETROM;
 		sax->fsa_ax25.sax25_ndigis = 1;
 		sax->fsa_ax25.sax25_call   = nr->user_addr;
+		memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
 		sax->fsa_digipeater[0]     = nr->dest_addr;
 		*uaddr_len = sizeof(struct full_sockaddr_ax25);
 	} else {