Repository : ssh://git@open-mesh.org/batman-adv

On branch : master

commit 04614cb8702d557e24f2181412abdf200d4ffe43 Author: Sven Eckelmann sven@narfation.org Date: Mon Apr 11 13:06:40 2016 +0200

batman-adv: Use kref_get for hard_iface subfunctions

The callers of the functions using batadv_hard_iface objects already make sure that they hold a valid reference. The subfunctions don't have to check whether the reference counter is > 0 because this was checked by the callers.

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

04614cb8702d557e24f2181412abdf200d4ffe43 net/batman-adv/bat_iv_ogm.c | 14 +++----------- net/batman-adv/hard-interface.c | 7 +++---- net/batman-adv/originator.c | 30 +++++++----------------------- 3 files changed, 13 insertions(+), 38 deletions(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index b390ff9..395019f 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -679,18 +679,12 @@ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff, unsigned char *skb_buff; unsigned int skb_size;

- if (!kref_get_unless_zero(&if_incoming->refcount)) - return; - - if (!kref_get_unless_zero(&if_outgoing->refcount)) - goto out_free_incoming; - /* own packet should always be scheduled */ if (!own_packet) { if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "batman packet queue full\n"); - goto out_free_outgoing; + return; } }

@@ -716,6 +710,8 @@ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff, forw_packet_aggr->packet_len = packet_len; memcpy(skb_buff, packet_buff, packet_len);

+ kref_get(&if_incoming->refcount); + kref_get(&if_outgoing->refcount); forw_packet_aggr->own = own_packet; forw_packet_aggr->if_incoming = if_incoming; forw_packet_aggr->if_outgoing = if_outgoing; @@ -745,10 +741,6 @@ out_free_forw_packet: out_nomem: if (!own_packet) atomic_inc(&bat_priv->batman_queue_left); -out_free_outgoing: - batadv_hardif_put(if_outgoing); -out_free_incoming: - batadv_hardif_put(if_incoming); }

/* aggregate a new packet into the existing ogm packet */ diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 22cc5ec..1ef180a 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -236,8 +236,8 @@ static void batadv_primary_if_select(struct batadv_priv *bat_priv,

ASSERT_RTNL();

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

curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1); rcu_assign_pointer(bat_priv->primary_if, new_hard_iface); @@ -464,8 +464,7 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) goto out;

- if (!kref_get_unless_zero(&hard_iface->refcount)) - goto out; + kref_get(&hard_iface->refcount);

soft_iface = dev_get_by_name(&init_net, iface_name);

diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 275de41..0f50c43 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -381,12 +381,8 @@ batadv_orig_ifinfo_new(struct batadv_orig_node *orig_node, if (!orig_ifinfo) goto out;

- if (if_outgoing != BATADV_IF_DEFAULT && - !kref_get_unless_zero(&if_outgoing->refcount)) { - kfree(orig_ifinfo); - orig_ifinfo = NULL; - goto out; - } + if (if_outgoing != BATADV_IF_DEFAULT) + kref_get(&if_outgoing->refcount);

reset_time = jiffies - 1; reset_time -= msecs_to_jiffies(BATADV_RESET_PROTECTION_MS); @@ -462,11 +458,8 @@ batadv_neigh_ifinfo_new(struct batadv_neigh_node *neigh, if (!neigh_ifinfo) goto out;

- if (if_outgoing && !kref_get_unless_zero(&if_outgoing->refcount)) { - kfree(neigh_ifinfo); - neigh_ifinfo = NULL; - goto out; - } + if (if_outgoing) + kref_get(&if_outgoing->refcount);

INIT_HLIST_NODE(&neigh_ifinfo->list); kref_init(&neigh_ifinfo->refcount); @@ -539,15 +532,11 @@ batadv_hardif_neigh_create(struct batadv_hard_iface *hard_iface, if (hardif_neigh) goto out;

- if (!kref_get_unless_zero(&hard_iface->refcount)) - goto out; - hardif_neigh = kzalloc(sizeof(*hardif_neigh), GFP_ATOMIC); - if (!hardif_neigh) { - batadv_hardif_put(hard_iface); + if (!hardif_neigh) goto out; - }

+ kref_get(&hard_iface->refcount); INIT_HLIST_NODE(&hardif_neigh->list); ether_addr_copy(hardif_neigh->addr, neigh_addr); hardif_neigh->if_incoming = hard_iface; @@ -650,16 +639,11 @@ batadv_neigh_node_new(struct batadv_orig_node *orig_node, if (!neigh_node) goto out;

- if (!kref_get_unless_zero(&hard_iface->refcount)) { - kfree(neigh_node); - neigh_node = NULL; - goto out; - } - INIT_HLIST_NODE(&neigh_node->list); INIT_HLIST_HEAD(&neigh_node->ifinfo_list); spin_lock_init(&neigh_node->ifinfo_lock);

+ kref_get(&hard_iface->refcount); ether_addr_copy(neigh_node->addr, neigh_addr); neigh_node->if_incoming = hard_iface; neigh_node->orig_node = orig_node;