On 14/01/14 08:41, Ying Xue wrote:

The following call chains indicate that batadv_is_on_batman_iface() is always under rtnl_lock protection as call_netdevice_notifier() is protected by rtnl_lock. So if __dev_get_by_index() rather than dev_get_by_index() is used to find interface handler in it, this would help us avoid to change interface reference counter.

call_netdevice_notifier() batadv_hard_if_event() batadv_hardif_add_interface() batadv_is_valid_iface() batadv_is_on_batman_iface()

Cc: Antonio Quartulli antonio@meshcoding.com Signed-off-by: Ying Xue ying.xue@windriver.com

Acked-by: Antonio Quartulli antonio@meshcoding.com

---

net/batman-adv/hard-interface.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index bebd46c..115d14e 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -86,15 +86,13 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev) return false;

/* recurse over the parent device */

• parent_dev = dev_get_by_index(&init_net, net_dev->iflink);

• parent_dev = __dev_get_by_index(&init_net, net_dev->iflink); /* if we got a NULL parent_dev there is something broken.. */ if (WARN(!parent_dev, "Cannot find parent device")) return false;

  ret = batadv_is_on_batman_iface(parent_dev);

• if (parent_dev)

• dev_put(parent_dev);
  

  return ret;

}