net/appletalk: Fix kernel memory disclosure

BugLink: http://bugs.launchpad.net/bugs/1745046

[ Upstream commit ce7e40c4 ]

ipddp_route structs contain alignment padding so kernel heap memory
is leaked when they are copied to user space in
ipddp_ioctl(SIOCFINDIPDDPRT). Change kmalloc() to kzalloc() to clear
that memory.
Signed-off-by: Vlad Tsyrklevich <vlad@tsyrklevich.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

drivers/net/appletalk/ipddp.c

@@ -191,7 +191,7 @@ static netdev_tx_t ipddp_xmit(struct sk_buff *skb, struct net_device *dev)
  */
 static int ipddp_create(struct ipddp_route *new_rt)
 {
-        struct ipddp_route *rt = kmalloc(sizeof(*rt), GFP_KERNEL);
+        struct ipddp_route *rt = kzalloc(sizeof(*rt), GFP_KERNEL);
 
         if (rt == NULL)
                 return -ENOMEM;