[PATCH] batman-adv: mcast: fix memory leak on deleting a batman-adv interface

[Linus Lüssing]

The batman-adv multicast tracker TVLV handler is registered for the
new batman-adv multicast packet type upon creating a batman-adv interface,
but not unregistered again upon the interface's deletion, leading to a
memory leak.

Fix this memory leak by calling the according TVLV handler unregister
routine for the multicast tracker TVLV upon batman-adv interface
deletion.

Fixes: 8ed36122d709 ("batman-adv: mcast: implement multicast packet reception 
and forwarding")
Reported-by: syzbot+ebe64cc5950868e77...@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000beadc4060f0cb...@google.com/
Signed-off-by: Linus Lüssing <linus.luess...@c0d3.blue>
---
 net/batman-adv/multicast.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index c8620905c2dc..38fab5e46ae2 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -2183,6 +2183,7 @@ void batadv_mcast_free(struct batadv_priv *bat_priv)
        cancel_delayed_work_sync(&bat_priv->mcast.work);
 
        batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
+       batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST_TRACKER, 1);
        batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
 
        /* safely calling outside of worker, as worker was canceled above */
-- 
2.43.0