Commit 6da7be7d authored by Sven Eckelmann's avatar Sven Eckelmann Committed by Simon Wunderlich
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batman-adv: Fix debugfs path for renamed softif 



batman-adv is creating special debugfs directories in the init
net_namespace for each created soft-interface (batadv net_device). But it
is possible to rename a net_device to a completely different name then the
original one.

It can therefore happen that a user registers a new batadv net_device with
the name "bat0". batman-adv is then also adding a new directory under
$debugfs/batman-adv/ with the name "wlan0".

The user then decides to rename this device to "bat1" and registers a
different batadv device with the name "bat0". batman-adv will then try to
create a directory with the name "bat0" under $debugfs/batman-adv/ again.
But there already exists one with this name under this path and thus this
fails. batman-adv will detect a problem and rollback the registering of
this device.

batman-adv must therefore take care of renaming the debugfs directories for
soft-interfaces whenever it detects such a net_device rename.

Fixes: c6c8fea2 ("net: Add batman-adv meshing protocol")
Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
Signed-off-by: default avatarSimon Wunderlich <sw@simonwunderlich.de>
parent 36dc621c

net/batman-adv/debugfs.c

+20 −0
Original line number Diff line number Diff line
@@ -433,6 +433,26 @@ out: 
	return -ENOMEM;

}



/**

 * batadv_debugfs_rename_meshif() - Fix debugfs path for renamed softif

 * @dev: net_device which was renamed

 */

void batadv_debugfs_rename_meshif(struct net_device *dev)

{

	struct batadv_priv *bat_priv = netdev_priv(dev);

	const char *name = dev->name;

	struct dentry *dir;

	struct dentry *d;



	dir = bat_priv->debug_dir;

	if (!dir)

		return;



	d = debugfs_rename(dir->d_parent, dir, dir->d_parent, name);

	if (!d)

		pr_err("Can't rename debugfs dir to %s\n", name);

}



/**

 * batadv_debugfs_del_meshif() - Remove interface dependent debugfs entries

 * @dev: netdev struct of the soft interface

net/batman-adv/debugfs.h

+5 −0
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ struct net_device; 
void batadv_debugfs_init(void);

void batadv_debugfs_destroy(void);

int batadv_debugfs_add_meshif(struct net_device *dev);

void batadv_debugfs_rename_meshif(struct net_device *dev);

void batadv_debugfs_del_meshif(struct net_device *dev);

int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface);

void batadv_debugfs_rename_hardif(struct batadv_hard_iface *hard_iface);
@@ -50,6 +51,10 @@ static inline int batadv_debugfs_add_meshif(struct net_device *dev) 
	return 0;

}



static inline void batadv_debugfs_rename_meshif(struct net_device *dev)

{

}



static inline void batadv_debugfs_del_meshif(struct net_device *dev)

{

}

net/batman-adv/hard-interface.c

+28 −6
Original line number Diff line number Diff line
@@ -989,21 +989,43 @@ void batadv_hardif_remove_interfaces(void) 
	rtnl_unlock();

}



static int batadv_hard_if_event(struct notifier_block *this,

				unsigned long event, void *ptr)

/**

 * batadv_hard_if_event_softif() - Handle events for soft interfaces

 * @event: NETDEV_* event to handle

 * @net_dev: net_device which generated an event

 *

 * Return: NOTIFY_* result

 */

static int batadv_hard_if_event_softif(unsigned long event,

				       struct net_device *net_dev)

{

	struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);

	struct batadv_hard_iface *hard_iface;

	struct batadv_hard_iface *primary_if = NULL;

	struct batadv_priv *bat_priv;



	if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {

	switch (event) {

	case NETDEV_REGISTER:

		batadv_sysfs_add_meshif(net_dev);

		bat_priv = netdev_priv(net_dev);

		batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);

		break;

	case NETDEV_CHANGENAME:

		batadv_debugfs_rename_meshif(net_dev);

		break;

	}



	return NOTIFY_DONE;

}



static int batadv_hard_if_event(struct notifier_block *this,

				unsigned long event, void *ptr)

{

	struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);

	struct batadv_hard_iface *hard_iface;

	struct batadv_hard_iface *primary_if = NULL;

	struct batadv_priv *bat_priv;



	if (batadv_softif_is_valid(net_dev))

		return batadv_hard_if_event_softif(event, net_dev);



	hard_iface = batadv_hardif_get_by_netdev(net_dev);

	if (!hard_iface && (event == NETDEV_REGISTER ||

			    event == NETDEV_POST_TYPE_CHANGE))

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