batman-adv: Increase orig_node refcount before releasing rcu read lock

When unicast_send_skb() is increasing the orig_node's refcount another
thread might have been freeing this orig_node already. We need to
increase the refcount in the rcu read lock protected area to avoid that.

Signed-off-by: Linus Lüssing <linus.luessing@ascom.ch>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
This commit is contained in:
Linus Lüssing 2011-02-13 21:13:04 +00:00 committed by Marek Lindner
parent 5d02b3cdfa
commit 43c70ad5ce
2 changed files with 5 additions and 3 deletions

View File

@ -54,6 +54,9 @@ void *gw_get_selected(struct bat_priv *bat_priv)
orig_node = curr_gateway_tmp->orig_node;
if (orig_node)
kref_get(&orig_node->refcount);
out:
rcu_read_unlock();
return orig_node;

View File

@ -293,10 +293,9 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
spin_lock_bh(&bat_priv->orig_hash_lock);
/* get routing information */
if (is_multicast_ether_addr(ethhdr->h_dest))
if (is_multicast_ether_addr(ethhdr->h_dest)) {
orig_node = (struct orig_node *)gw_get_selected(bat_priv);
if (orig_node) {
kref_get(&orig_node->refcount);
if (orig_node)
goto find_router;
}