pcmcia: synclink_cs: fix information leak to userland

Structure new_line is copied to userland with some padding fields unitialized.
It leads to leaking of stack memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
CC: stable@kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

drivers/char/pcmcia/synclink_cs.c

@@ -4097,6 +4097,8 @@ static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 	if (cmd != SIOCWANDEV)
 		return hdlc_ioctl(dev, ifr, cmd);
 
+	memset(&new_line, 0, size);
+
 	switch(ifr->ifr_settings.type) {
 	case IF_GET_IFACE: /* return current sync_serial_settings */