batman-adv: Make bat_priv->primary_if an rcu protected pointer
The rcu protected macros rcu_dereference() and rcu_assign_pointer()
for the bat_priv->primary_if need to be used, as well as spin/rcu locking.
Otherwise we might end up using a primary_if pointer pointing to already
freed memory.
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index af128ef..65f3953 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -439,30 +439,32 @@
{
struct net_device *net_dev = (struct net_device *)seq->private;
struct bat_priv *bat_priv = netdev_priv(net_dev);
+ struct hard_iface *primary_if;
struct gw_node *gw_node;
struct hlist_node *node;
- int gw_count = 0;
+ int gw_count = 0, ret = 0;
- if (!bat_priv->primary_if) {
-
- return seq_printf(seq, "BATMAN mesh %s disabled - please "
- "specify interfaces to enable it\n",
- net_dev->name);
+ primary_if = primary_if_get_selected(bat_priv);
+ if (!primary_if) {
+ ret = seq_printf(seq, "BATMAN mesh %s disabled - please "
+ "specify interfaces to enable it\n",
+ net_dev->name);
+ goto out;
}
- if (bat_priv->primary_if->if_status != IF_ACTIVE) {
-
- return seq_printf(seq, "BATMAN mesh %s disabled - "
- "primary interface not active\n",
- net_dev->name);
+ if (primary_if->if_status != IF_ACTIVE) {
+ ret = seq_printf(seq, "BATMAN mesh %s disabled - "
+ "primary interface not active\n",
+ net_dev->name);
+ goto out;
}
seq_printf(seq, " %-12s (%s/%i) %17s [%10s]: gw_class ... "
"[B.A.T.M.A.N. adv %s%s, MainIF/MAC: %s/%pM (%s)]\n",
"Gateway", "#", TQ_MAX_VALUE, "Nexthop",
"outgoingIF", SOURCE_VERSION, REVISION_VERSION_STR,
- bat_priv->primary_if->net_dev->name,
- bat_priv->primary_if->net_dev->dev_addr, net_dev->name);
+ primary_if->net_dev->name,
+ primary_if->net_dev->dev_addr, net_dev->name);
rcu_read_lock();
hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
@@ -480,7 +482,10 @@
if (gw_count == 0)
seq_printf(seq, "No gateways in range ...\n");
- return 0;
+out:
+ if (primary_if)
+ hardif_free_ref(primary_if);
+ return ret;
}
int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb)