The following commit has been merged in the master branch: commit a08d497d6718d579e496a801115aecc1c4fbb770 Author: Sven Eckelmann sven@narfation.org Date: Sat Mar 5 16:09:22 2016 +0100

batman-adv: Use kref_get for batadv_gw_select

batadv_gw_select requires that the caller already has a valid reference for new_gw_node. It is therefore not possible that it has an reference counter of 0 and was still given to this function

The kref_get function instead WARNs (with debug information) when the reference counter would still be 0. This makes a bug in batman-adv better visible because kref_get_unless_zero would have ignored this problem.

Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Marek Lindner mareklindner@neomailbox.ch Signed-off-by: Antonio Quartulli a@unstable.cc

diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c index c59aff5..bb1c4f3 100644 --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -135,8 +135,8 @@ static void batadv_gw_select(struct batadv_priv *bat_priv,

spin_lock_bh(&bat_priv->gw.list_lock);

- if (new_gw_node && !kref_get_unless_zero(&new_gw_node->refcount)) - new_gw_node = NULL; + if (new_gw_node) + kref_get(&new_gw_node->refcount);

curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1); rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);