commit f2d23861b818d08bcd15cc1612ae94aa33b3931c upstream.
The shutdown of an batman-adv interface can happen with one of its slave
interfaces still being in the BATADV_IF_TO_BE_ACTIVATED state. A possible
reason for it is that the routing algorithm BATMAN_V was selected and
batadv_schedule_bat_ogm was not yet called for this interface. This slave
interface still has to be set to BATADV_IF_INACTIVE or the batman-adv
interface will never reduce its usage counter and thus never gets shutdown.
This problem can be simulated via:
$ modprobe dummy
$ modprobe batman-adv routing_algo=BATMAN_V
$ ip link add bat0 type batadv
$ ip link set dummy0 master bat0
$ ip link set dummy0 up
$ ip link del bat0
unregister_netdevice: waiting for bat0 to become free. Usage count = 3
Reported-by: Matthias Schiffer <mschiffer@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx>
Signed-off-by: Marek Lindner <mareklindner@xxxxxxxxxxxxx>
Signed-off-by: Antonio Quartulli <a@xxxxxxxxxxx>
---
net/batman-adv/hard-interface.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index 933f36012ae6..ecaa68ae62f5 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -562,8 +562,7 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct batadv_hard_iface *primary_if = NULL;
- if (hard_iface->if_status == BATADV_IF_ACTIVE)
- batadv_hardif_deactivate_interface(hard_iface);
+ batadv_hardif_deactivate_interface(hard_iface);
if (hard_iface->if_status != BATADV_IF_INACTIVE)
goto out;
--
2.20.1
