Commit a5256f7e authored Aug 04, 2015 by Antonio Quartulli

batman-adv: don't access unregistered net_device object



In batadv_hardif_disable_interface() there is a call to
batadv_softif_destroy_sysfs() which in turns invokes
unregister_netdevice() on the soft_iface.
After this point we cannot rely on the soft_iface object
anymore because it might get free'd by the netdev periodic
routine at any time.

For this reason the netdev_upper_dev_unlink(.., soft_iface) call
is moved before the invocation of batadv_softif_destroy_sysfs() so
that we can be sure that the soft_iface object is still valid.

Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>

parent 07c48eca

net/batman-adv/hard-interface.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -528,6 +528,8 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
		batadv_purge_outstanding_packets(bat_priv, hard_iface);
		dev_put(hard_iface->soft_iface);

		netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);

		/* nobody uses this interface anymore */
		if (!bat_priv->num_ifaces) {
		batadv_gw_check_client_stop(bat_priv);
		@@ -536,7 +538,6 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
		batadv_softif_destroy_sysfs(hard_iface->soft_iface);
		}

		netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
		hard_iface->soft_iface = NULL;
		batadv_hardif_free_ref(hard_iface);