Merge tag 'batman-adv-fix-for-davem' of git://git.open-mesh.org/linux-merge
Included changes:
- properly release neigh_ifinfo in batadv_iv_ogm_process_per_outif()
- properly release orig_ifinfo->router when freeing orig_ifinfo
- properly release neigh_node objects during periodic check
- properly release neigh_info objects when the related hard_iface
is free'd
These changes are all very important because they fix some
reference counting imbalances that lead to the
impossibility of releasing the netdev object used by
batman-adv on shutdown.
The consequence is that such object cannot be destroyed by
the networking stack (the refcounter does not reach zero)
thus bringing the system in hanging state during a normal
reboot operation or a network reconfiguration.
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index b3bd4ec..f04224c 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -1545,6 +1545,8 @@
if ((orig_neigh_node) && (!is_single_hop_neigh))
batadv_orig_node_free_ref(orig_neigh_node);
out:
+ if (router_ifinfo)
+ batadv_neigh_ifinfo_free_ref(router_ifinfo);
if (router)
batadv_neigh_node_free_ref(router);
if (router_router)
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index ffd9dfb..1785da3 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -501,12 +501,17 @@
static void batadv_orig_ifinfo_free_rcu(struct rcu_head *rcu)
{
struct batadv_orig_ifinfo *orig_ifinfo;
+ struct batadv_neigh_node *router;
orig_ifinfo = container_of(rcu, struct batadv_orig_ifinfo, rcu);
if (orig_ifinfo->if_outgoing != BATADV_IF_DEFAULT)
batadv_hardif_free_ref_now(orig_ifinfo->if_outgoing);
+ /* this is the last reference to this object */
+ router = rcu_dereference_protected(orig_ifinfo->router, true);
+ if (router)
+ batadv_neigh_node_free_ref_now(router);
kfree(orig_ifinfo);
}
@@ -702,6 +707,47 @@
}
/**
+ * batadv_purge_neigh_ifinfo - purge obsolete ifinfo entries from neighbor
+ * @bat_priv: the bat priv with all the soft interface information
+ * @neigh: orig node which is to be checked
+ */
+static void
+batadv_purge_neigh_ifinfo(struct batadv_priv *bat_priv,
+ struct batadv_neigh_node *neigh)
+{
+ struct batadv_neigh_ifinfo *neigh_ifinfo;
+ struct batadv_hard_iface *if_outgoing;
+ struct hlist_node *node_tmp;
+
+ spin_lock_bh(&neigh->ifinfo_lock);
+
+ /* for all ifinfo objects for this neighinator */
+ hlist_for_each_entry_safe(neigh_ifinfo, node_tmp,
+ &neigh->ifinfo_list, list) {
+ if_outgoing = neigh_ifinfo->if_outgoing;
+
+ /* always keep the default interface */
+ if (if_outgoing == BATADV_IF_DEFAULT)
+ continue;
+
+ /* don't purge if the interface is not (going) down */
+ if ((if_outgoing->if_status != BATADV_IF_INACTIVE) &&
+ (if_outgoing->if_status != BATADV_IF_NOT_IN_USE) &&
+ (if_outgoing->if_status != BATADV_IF_TO_BE_REMOVED))
+ continue;
+
+ batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+ "neighbor/ifinfo purge: neighbor %pM, iface: %s\n",
+ neigh->addr, if_outgoing->net_dev->name);
+
+ hlist_del_rcu(&neigh_ifinfo->list);
+ batadv_neigh_ifinfo_free_ref(neigh_ifinfo);
+ }
+
+ spin_unlock_bh(&neigh->ifinfo_lock);
+}
+
+/**
* batadv_purge_orig_ifinfo - purge obsolete ifinfo entries from originator
* @bat_priv: the bat priv with all the soft interface information
* @orig_node: orig node which is to be checked
@@ -800,6 +846,11 @@
hlist_del_rcu(&neigh_node->list);
batadv_neigh_node_free_ref(neigh_node);
+ } else {
+ /* only necessary if not the whole neighbor is to be
+ * deleted, but some interface has been removed.
+ */
+ batadv_purge_neigh_ifinfo(bat_priv, neigh_node);
}
}
@@ -857,7 +908,7 @@
{
struct batadv_neigh_node *best_neigh_node;
struct batadv_hard_iface *hard_iface;
- bool changed;
+ bool changed_ifinfo, changed_neigh;
if (batadv_has_timed_out(orig_node->last_seen,
2 * BATADV_PURGE_TIMEOUT)) {
@@ -867,10 +918,10 @@
jiffies_to_msecs(orig_node->last_seen));
return true;
}
- changed = batadv_purge_orig_ifinfo(bat_priv, orig_node);
- changed = changed || batadv_purge_orig_neighbors(bat_priv, orig_node);
+ changed_ifinfo = batadv_purge_orig_ifinfo(bat_priv, orig_node);
+ changed_neigh = batadv_purge_orig_neighbors(bat_priv, orig_node);
- if (!changed)
+ if (!changed_ifinfo && !changed_neigh)
return false;
/* first for NULL ... */