Commit 6116ba09 authored by Sven Eckelmann's avatar Sven Eckelmann Committed by Simon Wunderlich
Browse files

batman-adv: Request iflink once in batadv_get_real_netdevice 



There is no need to call dev_get_iflink multiple times for the same
net_device in batadv_get_real_netdevice. And since some of the
ndo_get_iflink callbacks are dynamic (for example via RCUs like in
vxcan_get_iflink), it could easily happen that the returned values are not
stable. The pre-checks before __dev_get_by_index are then of course bogus.

Fixes: 5ed4a460 ("batman-adv: additional checks for virtual interfaces on top of WiFi")
Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
Signed-off-by: default avatarSimon Wunderlich <sw@simonwunderlich.de>
parent 690bb6fb

net/batman-adv/hard-interface.c

+5 −4
Original line number Diff line number Diff line
@@ -215,14 +215,16 @@ static struct net_device *batadv_get_real_netdevice(struct net_device *netdev) 
	struct net_device *real_netdev = NULL;

	struct net *real_net;

	struct net *net;

	int ifindex;

	int iflink;



	ASSERT_RTNL();



	if (!netdev)

		return NULL;



	if (netdev->ifindex == dev_get_iflink(netdev)) {

	iflink = dev_get_iflink(netdev);



	if (netdev->ifindex == iflink) {

		dev_hold(netdev);

		return netdev;

	}
@@ -232,9 +234,8 @@ static struct net_device *batadv_get_real_netdevice(struct net_device *netdev) 
		goto out;



	net = dev_net(hard_iface->soft_iface);

	ifindex = dev_get_iflink(netdev);

	real_net = batadv_getlink_net(netdev, net);

	real_netdev = dev_get_by_index(real_net, ifindex);

	real_netdev = dev_get_by_index(real_net, iflink);



out:

	batadv_hardif_put(hard_iface);