batman-adv: avoid double free when orig_node initialization fails

In the failure path of the orig_node initialization routine
the orig_node->bat_iv.bcast_own field is free'd twice: first
in batadv_iv_ogm_orig_get() and then later in
batadv_orig_node_free_rcu().

Fix it by removing the kfree in batadv_iv_ogm_orig_get().
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>

net/batman-adv/bat_iv_ogm.c

@@ -241,18 +241,16 @@ batadv_iv_ogm_orig_get(struct batadv_priv *bat_priv, const uint8_t *addr)
 	size = bat_priv->num_ifaces * sizeof(uint8_t);
 	orig_node->bat_iv.bcast_own_sum = kzalloc(size, GFP_ATOMIC);
 	if (!orig_node->bat_iv.bcast_own_sum)
-		goto free_bcast_own;
+		goto free_orig_node;
 
 	hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
 				     batadv_choose_orig, orig_node,
 				     &orig_node->hash_entry);
 	if (hash_added != 0)
-		goto free_bcast_own;
+		goto free_orig_node;
 
 	return orig_node;
 
-free_bcast_own:
-	kfree(orig_node->bat_iv.bcast_own);
 free_orig_node:
 	/* free twice, as batadv_orig_node_new sets refcount to 2 */
 	batadv_orig_node_free_ref(orig_node);