xen-netback: free queues after freeing the net device

If a queue still has a NAPI instance added to the net device, freeing
the queues early results in a use-after-free.

The shouldn't ever happen because we disconnect and tear down all queues
before freeing the net device, but doing this makes it obviously safe.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Vrabel 2016-01-15 14:55:36 +00:00 committed by David S. Miller
parent 4a65852727
commit 9c6f3ffe82

View File

@ -685,22 +685,16 @@ void xenvif_deinit_queue(struct xenvif_queue *queue)
void xenvif_free(struct xenvif *vif)
{
struct xenvif_queue *queue = NULL;
struct xenvif_queue *queues = vif->queues;
unsigned int num_queues = vif->num_queues;
unsigned int queue_index;
unregister_netdev(vif->dev);
for (queue_index = 0; queue_index < num_queues; ++queue_index) {
queue = &vif->queues[queue_index];
xenvif_deinit_queue(queue);
}
vfree(vif->queues);
vif->queues = NULL;
vif->num_queues = 0;
free_netdev(vif->dev);
for (queue_index = 0; queue_index < num_queues; ++queue_index)
xenvif_deinit_queue(&queues[queue_index]);
vfree(queues);
module_put(THIS_MODULE);
}