3.16.61-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: David Vrabel <[email protected]> commit ad0681185770716523c81b156c44b9804d7b8ed2 upstream. xennet_remove() freed the queues before freeing the netdevice which results in a use-after-free when free_netdev() tries to delete the napi instances that have already been freed. Fix this by fully destroy the queues (which includes deleting the napi instances) before freeing the netdevice. Signed-off-by: David Vrabel <[email protected]> Reviewed-by: Boris Ostrovsky <[email protected]> Signed-off-by: David S. Miller <[email protected]> [bwh: Backported to 3.16: I already backported most of this along with the later commit 74470954857c "xen-netfront: Delete rx_refill_timer in xennet_disconnect_backend()"; don't move the del_timer_sync() again.] Signed-off-by: Ben Hutchings <[email protected]> --- --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -2294,7 +2294,6 @@ static const struct xenbus_device_id net static int xennet_remove(struct xenbus_device *dev) { struct netfront_info *info = dev_get_drvdata(&dev->dev); - unsigned int num_queues = info->netdev->real_num_tx_queues; dev_dbg(&dev->dev, "%s\n", dev->nodename); @@ -2302,11 +2301,7 @@ static int xennet_remove(struct xenbus_d unregister_netdev(info->netdev); - if (num_queues) { - kfree(info->queues); - info->queues = NULL; - } - + xennet_destroy_queues(info); xennet_free_netdev(info->netdev); return 0;
