| Message ID | 20160929152258.8217-1-sven.eckelmann@open-mesh.com |
|---|---|
| State | Accepted, archived |
| Commit | 0e384ddb1995ae400766cf33b95537fb115a7800 |
| Delegated to: | Sven Eckelmann |
| Headers | show |
On Thu, Sep 29, 2016 at 05:22:58PM +0200, Sven Eckelmann wrote: > 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: fed2826b490c ("batman-adv: add list of unique single hop neighbors per hard-interface") > Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com> Acked-by: Linus Lüssing <linus.luessing@c0d3.blue>
On Donnerstag, 29. September 2016 17:22:58 CEST Sven Eckelmann wrote: > 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: fed2826b490c ("batman-adv: add list of unique single hop neighbors > per hard-interface") Signed-off-by: Sven Eckelmann > <sven.eckelmann@open-mesh.com> > Acked-by: Linus Lüssing <linus.luessing@c0d3.blue> > --- > net/batman-adv/originator.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Applied in 0e384ddb1995ae400766cf33b95537fb115a7800 [1]. Kind regards, Sven [1] https://git.open-mesh.org/batman-adv.git/commit/0e384ddb1995ae400766cf33b95537fb115a7800
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 3940b5d..3e9667e 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -537,7 +537,7 @@ 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);
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: fed2826b490c ("batman-adv: add list of unique single hop neighbors per hard-interface") Signed-off-by: Sven Eckelmann <sven.eckelmann@open-mesh.com> --- net/batman-adv/originator.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)