From: Sven Eckelmann Date: Thu, 29 Sep 2016 15:22:58 +0000 (+0200) Subject: batman-adv: Modify neigh_list only with rcu-list functions X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9ca488dd53088d4fcc97258aeeccf21f63b7da1e;p=linux-beck.git batman-adv: Modify neigh_list only with rcu-list functions The batadv_hard_iface::neigh_list is accessed via rcu based primitives. Thus all operations done on it have to fulfill the requirements by RCU. So using non-RCU mechanisms like hlist_add_head is not allowed because it misses the barriers required to protect concurrent readers when accessing the data behind the pointer. Fixes: cef63419f7db ("batman-adv: add list of unique single hop neighbors per hard-interface") Signed-off-by: Sven Eckelmann Acked-by: Linus Lüssing Signed-off-by: Simon Wunderlich --- diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 5f3bfc41aeb1..7c8d16086f0f 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -544,7 +544,7 @@ batadv_hardif_neigh_create(struct batadv_hard_iface *hard_iface, if (bat_priv->algo_ops->neigh.hardif_init) bat_priv->algo_ops->neigh.hardif_init(hardif_neigh); - hlist_add_head(&hardif_neigh->list, &hard_iface->neigh_list); + hlist_add_head_rcu(&hardif_neigh->list, &hard_iface->neigh_list); out: spin_unlock_bh(&hard_iface->neigh_list_lock);