From: Sven Eckelmann sven@narfation.org
It is hard to understand why the refcnt is increased when it isn't done near the actual place the new reference is used. So using kref_get right before the place which requires the reference and in the same function helps to avoid accidental problems caused by incorrect reference counting.
Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Marek Lindner mareklindner@neomailbox.ch Signed-off-by: Simon Wunderlich sw@simonwunderlich.de --- net/batman-adv/gateway_client.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c index b889e1f..4b51b1c 100644 --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -339,14 +339,15 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv, if (!gw_node) return;
+ kref_init(&gw_node->refcount); INIT_HLIST_NODE(&gw_node->list); kref_get(&orig_node->refcount); gw_node->orig_node = orig_node; gw_node->bandwidth_down = ntohl(gateway->bandwidth_down); gw_node->bandwidth_up = ntohl(gateway->bandwidth_up); - kref_init(&gw_node->refcount);
spin_lock_bh(&bat_priv->gw.list_lock); + kref_get(&gw_node->refcount); hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list); spin_unlock_bh(&bat_priv->gw.list_lock);
@@ -357,6 +358,9 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv, ntohl(gateway->bandwidth_down) % 10, ntohl(gateway->bandwidth_up) / 10, ntohl(gateway->bandwidth_up) % 10); + + /* don't return reference to new gw_node */ + batadv_gw_node_put(gw_node); }
/**