[PATCH 3.16 169/366] net/xen-netfront: only clean up queues if present
From: Ben Hutchings
Date: Sun Nov 11 2018 - 15:37:21 EST
3.16.61-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Chas Williams <3chas3@xxxxxxxxx>
commit 9a873c71e91cabf4c10fd9bbd8358c22deaf6c9e upstream.
If you simply load and unload the module without starting the interfaces,
the queues are never created and you get a bad pointer dereference.
Signed-off-by: Chas Williams <3chas3@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/net/xen-netfront.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1422,7 +1422,7 @@ static void xennet_disconnect_backend(st
netif_carrier_off(info->netdev);
- for (i = 0; i < num_queues; ++i) {
+ for (i = 0; i < num_queues && info->queues; ++i) {
struct netfront_queue *queue = &info->queues[i];
del_timer_sync(&queue->rx_refill_timer);
@@ -2294,7 +2294,8 @@ static int xennet_remove(struct xenbus_d
unregister_netdev(info->netdev);
- xennet_destroy_queues(info);
+ if (info->queues)
+ xennet_destroy_queues(info);
xennet_free_netdev(info->netdev);
return 0;