batman-adv: Place kref_get for tt_local_entry near use

It is hard to understand why the refcnt is increased when it isn't done
near the actual place the new reference is used. So using kref_get right
before the place which requires the reference and in the same function
helps to avoid accidental problems caused by incorrect reference counting.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index 5cc500f..094da1a 100644 (file)
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -734,7 +734,6 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
        if (batadv_is_wifi_netdev(in_dev))
                tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
        kref_init(&tt_local->common.refcount);
-       kref_get(&tt_local->common.refcount);
        tt_local->last_seen = jiffies;
        tt_local->common.added_at = tt_local->last_seen;
        tt_local->vlan = vlan;
@@ -746,6 +745,7 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
            is_multicast_ether_addr(addr))
                tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;
 
+       kref_get(&tt_local->common.refcount);
        hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
                                     batadv_choose_tt, &tt_local->common,
                                     &tt_local->common.hash_entry);