linux/net/batman-adv/hard-interface.h
Marek Lindner 32ae9b221e batman-adv: Make bat_priv->primary_if an rcu protected pointer
The rcu protected macros rcu_dereference() and rcu_assign_pointer()
for the bat_priv->primary_if need to be used, as well as spin/rcu locking.

Otherwise we might end up using a primary_if pointer pointing to already
freed memory.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-05-01 22:49:03 +02:00

67 lines
2.0 KiB
C

/*
* Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
*
* Marek Lindner, Simon Wunderlich
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*
*/
#ifndef _NET_BATMAN_ADV_HARD_INTERFACE_H_
#define _NET_BATMAN_ADV_HARD_INTERFACE_H_
#define IF_NOT_IN_USE 0
#define IF_TO_BE_REMOVED 1
#define IF_INACTIVE 2
#define IF_ACTIVE 3
#define IF_TO_BE_ACTIVATED 4
#define IF_I_WANT_YOU 5
extern struct notifier_block hard_if_notifier;
struct hard_iface *hardif_get_by_netdev(struct net_device *net_dev);
int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name);
void hardif_disable_interface(struct hard_iface *hard_iface);
void hardif_remove_interfaces(void);
int hardif_min_mtu(struct net_device *soft_iface);
void update_min_mtu(struct net_device *soft_iface);
void hardif_free_rcu(struct rcu_head *rcu);
static inline void hardif_free_ref(struct hard_iface *hard_iface)
{
if (atomic_dec_and_test(&hard_iface->refcount))
call_rcu(&hard_iface->rcu, hardif_free_rcu);
}
static inline struct hard_iface *primary_if_get_selected(
struct bat_priv *bat_priv)
{
struct hard_iface *hard_iface;
rcu_read_lock();
hard_iface = rcu_dereference(bat_priv->primary_if);
if (!hard_iface)
goto out;
if (!atomic_inc_not_zero(&hard_iface->refcount))
hard_iface = NULL;
out:
rcu_read_unlock();
return hard_iface;
}
#endif /* _NET_BATMAN_ADV_HARD_INTERFACE_H_ */