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batman-adv: protect neigh_nodes used outside of rcu_locks with refcounting 

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
This commit is contained in:
Marek Lindner 2011-01-19 20:01:39 +00:00
parent 1a241a57be
commit a775eb847a
1 changed files with 31 additions and 9 deletions
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40
net/batman-adv/routing.c
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@ -151,6 +151,7 @@ static int is_bidirectional_neigh(struct orig_node *orig_node,
struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
struct hlist_node *node;
unsigned char total_count;
int ret = 0;
if (orig_node == orig_neigh_node) {
rcu_read_lock();
@ -162,7 +163,6 @@ static int is_bidirectional_neigh(struct orig_node *orig_node,
(tmp_neigh_node->if_incoming == if_incoming))
neigh_node = tmp_neigh_node;
}
rcu_read_unlock();
if (!neigh_node)
neigh_node = create_neighbor(orig_node,
@ -171,7 +171,10 @@ static int is_bidirectional_neigh(struct orig_node *orig_node,
if_incoming);
/* create_neighbor failed, return 0 */
if (!neigh_node)
return 0;
goto unlock;
kref_get(&neigh_node->refcount);
rcu_read_unlock();
neigh_node->last_valid = jiffies;
} else {
@ -185,7 +188,6 @@ static int is_bidirectional_neigh(struct orig_node *orig_node,
(tmp_neigh_node->if_incoming == if_incoming))
neigh_node = tmp_neigh_node;
}
rcu_read_unlock();
if (!neigh_node)
neigh_node = create_neighbor(orig_neigh_node,
@ -194,7 +196,10 @@ static int is_bidirectional_neigh(struct orig_node *orig_node,
if_incoming);
/* create_neighbor failed, return 0 */
if (!neigh_node)
return 0;
goto unlock;
kref_get(&neigh_node->refcount);
rcu_read_unlock();
}
orig_node->last_valid = jiffies;
@ -250,9 +255,16 @@ static int is_bidirectional_neigh(struct orig_node *orig_node,
/* if link has the minimum required transmission quality
* consider it bidirectional */
if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
return 1;
ret = 1;
return 0;
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
kref_put(&neigh_node->refcount, neigh_node_free_ref);
return ret;
}
static void update_orig(struct bat_priv *bat_priv,
@ -287,23 +299,25 @@ static void update_orig(struct bat_priv *bat_priv,
tmp_neigh_node->tq_avg =
ring_buffer_avg(tmp_neigh_node->tq_recv);
}
rcu_read_unlock();
if (!neigh_node) {
struct orig_node *orig_tmp;
orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
if (!orig_tmp)
return;
goto unlock;
neigh_node = create_neighbor(orig_node, orig_tmp,
ethhdr->h_source, if_incoming);
if (!neigh_node)
return;
goto unlock;
} else
bat_dbg(DBG_BATMAN, bat_priv,
"Updating existing last-hop neighbor of originator\n");
kref_get(&neigh_node->refcount);
rcu_read_unlock();
orig_node->flags = batman_packet->flags;
neigh_node->last_valid = jiffies;
@ -357,6 +371,14 @@ update_gw:
(atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
(atomic_read(&bat_priv->gw_sel_class) > 2))
gw_check_election(bat_priv, orig_node);
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
kref_put(&neigh_node->refcount, neigh_node_free_ref);
}
/* checks whether the host restarted and is in the protection time.