farsync: fix info leak in ioctl

[ Upstream commit 96b340406724d87e4621284ebac5e059d67b2194 ]

The fst_get_iface() code fails to initialize the two padding bytes of
struct sync_serial_settings after the ->loopback member. Add an explicit
memset(0) before filling the structure to avoid the info leak.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/net/wan/farsync.c b/drivers/net/wan/farsync.c
index ebb9f24..7a4c491 100644 (file)
--- a/drivers/net/wan/farsync.c
+++ b/drivers/net/wan/farsync.c
@@ -1972,6 +1972,7 @@ fst_get_iface(struct fst_card_info *card, struct fst_port_info *port,
        }
 
        i = port->index;
+       memset(&sync, 0, sizeof(sync));
        sync.clock_rate = FST_RDL(card, portConfig[i].lineSpeed);
        /* Lucky card and linux use same encoding here */
        sync.clock_type = FST_RDB(card, portConfig[i].internalClock) ==