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/bat_iv_ogm.c | 7 ++++--- net/batman-adv/bat_v_ogm.c | 5 ++--- net/batman-adv/gateway_client.c | 2 +- net/batman-adv/network-coding.c | 7 +++---- net/batman-adv/originator.c | 1 - 5 files changed, 10 insertions(+), 12 deletions(-)
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 9ed4f1f..3c7900d 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -324,17 +324,18 @@ batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const u8 *addr) if (!orig_node->bat_iv.bcast_own_sum) goto free_orig_node;
+ kref_get(&orig_node->refcount); hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig, batadv_choose_orig, orig_node, &orig_node->hash_entry); if (hash_added != 0) - goto free_orig_node; + goto free_orig_node_hash;
return orig_node;
-free_orig_node: - /* free twice, as batadv_orig_node_new sets refcount to 2 */ +free_orig_node_hash: batadv_orig_node_put(orig_node); +free_orig_node: batadv_orig_node_put(orig_node);
return NULL; diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index 6fbba4e..1aeeadc 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -73,13 +73,12 @@ struct batadv_orig_node *batadv_v_ogm_orig_get(struct batadv_priv *bat_priv, if (!orig_node) return NULL;
+ kref_get(&orig_node->refcount); hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig, batadv_choose_orig, orig_node, &orig_node->hash_entry); if (hash_added != 0) { - /* orig_node->refcounter is initialised to 2 by - * batadv_orig_node_new() - */ + /* remove refcnt for newly created orig_node and hash entry */ batadv_orig_node_put(orig_node); batadv_orig_node_put(orig_node); orig_node = NULL; diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c index c2928c2..b889e1f 100644 --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -339,8 +339,8 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv, if (!gw_node) return;
- kref_get(&orig_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); diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index 293ef4f..3814cfb 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -856,14 +856,13 @@ batadv_nc_get_nc_node(struct batadv_priv *bat_priv, if (!nc_node) return NULL;
- kref_get(&orig_neigh_node->refcount); - /* Initialize nc_node */ INIT_LIST_HEAD(&nc_node->list); - ether_addr_copy(nc_node->addr, orig_node->orig); - nc_node->orig_node = orig_neigh_node; kref_init(&nc_node->refcount); kref_get(&nc_node->refcount); + ether_addr_copy(nc_node->addr, orig_node->orig); + kref_get(&orig_neigh_node->refcount); + nc_node->orig_node = orig_neigh_node;
/* Select ingoing or outgoing coding node */ if (in_coding) { diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 0792de8..0b7d57a 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -989,7 +989,6 @@ struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv,
/* extra reference for return */ kref_init(&orig_node->refcount); - kref_get(&orig_node->refcount);
orig_node->bat_priv = bat_priv; ether_addr_copy(orig_node->orig, addr);