net: tipc: fix information leak to userland

commit 88f8a5e3e7defccd3925cabb1ee4d3994e5cdb52 upstream.

Structure sockaddr_tipc is copied to userland with padding bytes after
"id" field in union field "name" unitialized.  It leads to leaking of
contents of kernel stack memory.  We have to initialize them to zero.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Moritz Muehlenhoff <jmm@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 4b235fc1c70ff7948c372a6c0d36e7ca9b5ad39a..c7344c3608a89c1b7943db826bd0ab3542289d7a 100644 (file)
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -395,6 +395,7 @@ static int get_name(struct socket *sock, struct sockaddr *uaddr,
        struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
        struct tipc_sock *tsock = tipc_sk(sock->sk);
 
+       memset(addr, 0, sizeof(*addr));
        if (peer) {
                if ((sock->state != SS_CONNECTED) &&
                        ((peer != 2) || (sock->state != SS_DISCONNECTING)))