batman-adv: Use kref_get for batadv_nc_get_nc_node

batadv_nc_get_nc_node requires that the caller already has a valid
reference for orig_neigh_node. It is therefore not possible that it has an
reference counter of 0 and was still given to this function

The kref_get function instead WARNs (with debug information) when the
reference counter would still be 0. This makes a bug in batman-adv better
visible because kref_get_unless_zero would have ignored this problem.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>

diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c
index 1da8e0e..953dff1 100644 (file)
--- a/net/batman-adv/network-coding.c
+++ b/net/batman-adv/network-coding.c
@@ -856,8 +856,7 @@ batadv_nc_get_nc_node(struct batadv_priv *bat_priv,
        if (!nc_node)
                return NULL;
 
-       if (!kref_get_unless_zero(&orig_neigh_node->refcount))
-               goto free;
+       kref_get(&orig_neigh_node->refcount);
 
        /* Initialize nc_node */
        INIT_LIST_HEAD(&nc_node->list);
@@ -884,10 +883,6 @@ batadv_nc_get_nc_node(struct batadv_priv *bat_priv,
        spin_unlock_bh(lock);
 
        return nc_node;
-
-free:
-       kfree(nc_node);
-       return NULL;
 }
 
 /**