[PATCH 4.4 06/53] s390/qeth: avoid null pointer dereference on OSN

Greg Kroah-Hartman
2017-06-05T16:20:40Z

From: Julian Wiedmann <jwi@linux.vnet.ibm.com>

[ Upstream commit 25e2c341e7818a394da9abc403716278ee646014 ]

Access card->dev only after checking whether's its valid.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/s390/net/qeth_l2_main.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -1112,7 +1112,6 @@ static int qeth_l2_setup_netdev(struct q
case QETH_CARD_TYPE_OSN:
card->dev = alloc_netdev(0, "osn%d", NET_NAME_UNKNOWN,
ether_setup);
- card->dev->flags |= IFF_NOARP;
break;
default:
card->dev = alloc_etherdev(0);
@@ -1125,9 +1124,12 @@ static int qeth_l2_setup_netdev(struct q
card->dev->watchdog_timeo = QETH_TX_TIMEOUT;
card->dev->mtu = card->info.initial_mtu;
card->dev->netdev_ops = &qeth_l2_netdev_ops;
- card->dev->ethtool_ops =
- (card->info.type != QETH_CARD_TYPE_OSN) ?
- &qeth_l2_ethtool_ops : &qeth_l2_osn_ops;
+ if (card->info.type == QETH_CARD_TYPE_OSN) {
+ card->dev->ethtool_ops = &qeth_l2_osn_ops;
+ card->dev->flags |= IFF_NOARP;
+ } else {
+ card->dev->ethtool_ops = &qeth_l2_ethtool_ops;
+ }
card->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
if (card->info.type == QETH_CARD_TYPE_OSD && !card->info.guestlan) {
card->dev->hw_features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM;