batman-adv: clean untagged VLAN on netdev registration failure

commit 8669a550c7 upstream.

When an mesh interface is registered, it creates an untagged struct
batadv_meshif_vlan on top of it via the NETDEV_REGISTER notifier. But in
this process, another receiver of this notification can veto the
registration. The netdev registration will be aborted because of this veto.

The register_netdevice() call will try to clean up the net_device using
unregister_netdevice_queue() - which only uses the .priv_destructor to
free private resources. In this situation, .dellink will not be called.

The cleanup of the untagged batadv_meshif_vlan must thefore be done in the
destructor to avoid a leak of this object.

Cc: stable@vger.kernel.org
Fixes: 5d2c05b213 ("batman-adv: add per VLAN interface attribute framework")
[ switch to old "mesh_iface" name "soft_iface" ]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Sven Eckelmann
2026-07-24 16:03:43 +02:00
committed by Greg Kroah-Hartman
parent e6640923af
commit f2423da559
3 changed files with 12 additions and 11 deletions
+8
View File
@@ -258,6 +258,7 @@ err_orig:
void batadv_mesh_free(struct net_device *soft_iface)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct batadv_softif_vlan *vlan;
atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
@@ -273,6 +274,13 @@ void batadv_mesh_free(struct net_device *soft_iface)
batadv_mcast_free(bat_priv);
/* destroy the "untagged" VLAN */
vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
if (vlan) {
batadv_softif_destroy_vlan(bat_priv, vlan);
batadv_softif_vlan_put(vlan);
}
/* Free the TT and the originator tables only after having terminated
* all the other depending components which may use these structures for
* their purposes.
+2 -11
View File
@@ -603,8 +603,8 @@ int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
* @bat_priv: the bat priv with all the soft interface information
* @vlan: the object to remove
*/
static void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
struct batadv_softif_vlan *vlan)
void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
struct batadv_softif_vlan *vlan)
{
/* explicitly remove the associated TT local entry because it is marked
* with the NOPURGE flag
@@ -1086,22 +1086,13 @@ static int batadv_softif_newlink(struct net *src_net, struct net_device *dev,
static void batadv_softif_destroy_netlink(struct net_device *soft_iface,
struct list_head *head)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct batadv_hard_iface *hard_iface;
struct batadv_softif_vlan *vlan;
list_for_each_entry(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface == soft_iface)
batadv_hardif_disable_interface(hard_iface);
}
/* destroy the "untagged" VLAN */
vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
if (vlan) {
batadv_softif_destroy_vlan(bat_priv, vlan);
batadv_softif_vlan_put(vlan);
}
unregister_netdevice_queue(soft_iface, head);
}
+2
View File
@@ -22,6 +22,8 @@ void batadv_interface_rx(struct net_device *soft_iface,
bool batadv_softif_is_valid(const struct net_device *net_dev);
extern struct rtnl_link_ops batadv_link_ops;
int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid);
void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
struct batadv_softif_vlan *vlan);
void batadv_softif_vlan_release(struct kref *ref);
struct batadv_softif_vlan *batadv_softif_vlan_get(struct batadv_priv *bat_priv,
unsigned short vid);