From c91265cd0efb83778f015b4d4b1129bd2cfd075e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Sat, 14 May 2016 05:45:59 -0300 Subject: Linux-libre 4.5.4-gnu --- net/batman-adv/routing.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'net/batman-adv/routing.c') diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index e4f2646d9..43d15d6c4 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -104,6 +104,15 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, neigh_node = NULL; spin_lock_bh(&orig_node->neigh_list_lock); + /* curr_router used earlier may not be the current orig_ifinfo->router + * anymore because it was dereferenced outside of the neigh_list_lock + * protected region. After the new best neighbor has replace the current + * best neighbor the reference counter needs to decrease. Consequently, + * the code needs to ensure the curr_router variable contains a pointer + * to the replaced best neighbor. + */ + curr_router = rcu_dereference_protected(orig_ifinfo->router, true); + rcu_assign_pointer(orig_ifinfo->router, neigh_node); spin_unlock_bh(&orig_node->neigh_list_lock); batadv_orig_ifinfo_free_ref(orig_ifinfo); -- cgit v1.2.3