linux/net/batman-adv/types.h
Marek Lindner 7d2b554826 batman-adv: Correct rcu refcounting for softif_neigh
It might be possible that 2 threads access the same data in the same
rcu grace period. The first thread calls call_rcu() to decrement the
refcount and free the data while the second thread increases the
refcount to use the data. To avoid this race condition all refcount
operations have to be atomic.

Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:05 +01:00

276 lines
7.3 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_TYPES_H_
#define _NET_BATMAN_ADV_TYPES_H_
#include "packet.h"
#include "bitarray.h"
#define BAT_HEADER_LEN (sizeof(struct ethhdr) + \
((sizeof(struct unicast_packet) > sizeof(struct bcast_packet) ? \
sizeof(struct unicast_packet) : \
sizeof(struct bcast_packet))))
struct batman_if {
struct list_head list;
int16_t if_num;
char if_status;
struct net_device *net_dev;
atomic_t seqno;
atomic_t frag_seqno;
unsigned char *packet_buff;
int packet_len;
struct kobject *hardif_obj;
struct kref refcount;
struct packet_type batman_adv_ptype;
struct net_device *soft_iface;
struct rcu_head rcu;
};
/**
* orig_node - structure for orig_list maintaining nodes of mesh
* @primary_addr: hosts primary interface address
* @last_valid: when last packet from this node was received
* @bcast_seqno_reset: time when the broadcast seqno window was reset
* @batman_seqno_reset: time when the batman seqno window was reset
* @gw_flags: flags related to gateway class
* @flags: for now only VIS_SERVER flag
* @last_real_seqno: last and best known squence number
* @last_ttl: ttl of last received packet
* @last_bcast_seqno: last broadcast sequence number received by this host
*
* @candidates: how many candidates are available
* @selected: next bonding candidate
*/
struct orig_node {
uint8_t orig[ETH_ALEN];
uint8_t primary_addr[ETH_ALEN];
struct neigh_node *router;
unsigned long *bcast_own;
uint8_t *bcast_own_sum;
uint8_t tq_own;
int tq_asym_penalty;
unsigned long last_valid;
unsigned long bcast_seqno_reset;
unsigned long batman_seqno_reset;
uint8_t gw_flags;
uint8_t flags;
unsigned char *hna_buff;
int16_t hna_buff_len;
uint32_t last_real_seqno;
uint8_t last_ttl;
unsigned long bcast_bits[NUM_WORDS];
uint32_t last_bcast_seqno;
struct hlist_head neigh_list;
struct list_head frag_list;
spinlock_t neigh_list_lock; /* protects neighbor list */
struct kref refcount;
struct bat_priv *bat_priv;
unsigned long last_frag_packet;
spinlock_t ogm_cnt_lock; /* protects ogm counter */
atomic_t bond_candidates;
struct list_head bond_list;
};
struct gw_node {
struct hlist_node list;
struct orig_node *orig_node;
unsigned long deleted;
atomic_t refcount;
struct rcu_head rcu;
};
/**
* neigh_node
* @last_valid: when last packet via this neighbor was received
*/
struct neigh_node {
struct hlist_node list;
uint8_t addr[ETH_ALEN];
uint8_t real_packet_count;
uint8_t tq_recv[TQ_GLOBAL_WINDOW_SIZE];
uint8_t tq_index;
uint8_t tq_avg;
uint8_t last_ttl;
struct list_head bonding_list;
unsigned long last_valid;
unsigned long real_bits[NUM_WORDS];
atomic_t refcount;
struct rcu_head rcu;
struct orig_node *orig_node;
struct batman_if *if_incoming;
};
struct bat_priv {
atomic_t mesh_state;
struct net_device_stats stats;
atomic_t aggregated_ogms; /* boolean */
atomic_t bonding; /* boolean */
atomic_t fragmentation; /* boolean */
atomic_t vis_mode; /* VIS_TYPE_* */
atomic_t gw_mode; /* GW_MODE_* */
atomic_t gw_sel_class; /* uint */
atomic_t gw_bandwidth; /* gw bandwidth */
atomic_t orig_interval; /* uint */
atomic_t hop_penalty; /* uint */
atomic_t log_level; /* uint */
atomic_t bcast_seqno;
atomic_t bcast_queue_left;
atomic_t batman_queue_left;
char num_ifaces;
struct hlist_head softif_neigh_list;
struct softif_neigh *softif_neigh;
struct debug_log *debug_log;
struct batman_if *primary_if;
struct kobject *mesh_obj;
struct dentry *debug_dir;
struct hlist_head forw_bat_list;
struct hlist_head forw_bcast_list;
struct hlist_head gw_list;
struct list_head vis_send_list;
struct hashtable_t *orig_hash;
struct hashtable_t *hna_local_hash;
struct hashtable_t *hna_global_hash;
struct hashtable_t *vis_hash;
spinlock_t orig_hash_lock; /* protects orig_hash */
spinlock_t forw_bat_list_lock; /* protects forw_bat_list */
spinlock_t forw_bcast_list_lock; /* protects */
spinlock_t hna_lhash_lock; /* protects hna_local_hash */
spinlock_t hna_ghash_lock; /* protects hna_global_hash */
spinlock_t gw_list_lock; /* protects gw_list */
spinlock_t vis_hash_lock; /* protects vis_hash */
spinlock_t vis_list_lock; /* protects vis_info::recv_list */
spinlock_t softif_neigh_lock; /* protects soft-interface neigh list */
int16_t num_local_hna;
atomic_t hna_local_changed;
struct delayed_work hna_work;
struct delayed_work orig_work;
struct delayed_work vis_work;
struct gw_node *curr_gw;
struct vis_info *my_vis_info;
};
struct socket_client {
struct list_head queue_list;
unsigned int queue_len;
unsigned char index;
spinlock_t lock; /* protects queue_list, queue_len, index */
wait_queue_head_t queue_wait;
struct bat_priv *bat_priv;
};
struct socket_packet {
struct list_head list;
size_t icmp_len;
struct icmp_packet_rr icmp_packet;
};
struct hna_local_entry {
uint8_t addr[ETH_ALEN];
unsigned long last_seen;
char never_purge;
};
struct hna_global_entry {
uint8_t addr[ETH_ALEN];
struct orig_node *orig_node;
};
/**
* forw_packet - structure for forw_list maintaining packets to be
* send/forwarded
*/
struct forw_packet {
struct hlist_node list;
unsigned long send_time;
uint8_t own;
struct sk_buff *skb;
uint16_t packet_len;
uint32_t direct_link_flags;
uint8_t num_packets;
struct delayed_work delayed_work;
struct batman_if *if_incoming;
};
/* While scanning for vis-entries of a particular vis-originator
* this list collects its interfaces to create a subgraph/cluster
* out of them later
*/
struct if_list_entry {
uint8_t addr[ETH_ALEN];
bool primary;
struct hlist_node list;
};
struct debug_log {
char log_buff[LOG_BUF_LEN];
unsigned long log_start;
unsigned long log_end;
spinlock_t lock; /* protects log_buff, log_start and log_end */
wait_queue_head_t queue_wait;
};
struct frag_packet_list_entry {
struct list_head list;
uint16_t seqno;
struct sk_buff *skb;
};
struct vis_info {
unsigned long first_seen;
struct list_head recv_list;
/* list of server-neighbors we received a vis-packet
* from. we should not reply to them. */
struct list_head send_list;
struct kref refcount;
struct bat_priv *bat_priv;
/* this packet might be part of the vis send queue. */
struct sk_buff *skb_packet;
/* vis_info may follow here*/
} __packed;
struct vis_info_entry {
uint8_t src[ETH_ALEN];
uint8_t dest[ETH_ALEN];
uint8_t quality; /* quality = 0 means HNA */
} __packed;
struct recvlist_node {
struct list_head list;
uint8_t mac[ETH_ALEN];
};
struct softif_neigh {
struct hlist_node list;
uint8_t addr[ETH_ALEN];
unsigned long last_seen;
short vid;
atomic_t refcount;
struct rcu_head rcu;
};
#endif /* _NET_BATMAN_ADV_TYPES_H_ */