linux/net/mac80211/mesh_pathtbl.c
Nicolas Escande b7d7f11a29 wifi: mac80211: mesh: Fix leak of mesh_preq_queue objects
The hwmp code use objects of type mesh_preq_queue, added to a list in
ieee80211_if_mesh, to keep track of mpath we need to resolve. If the mpath
gets deleted, ex mesh interface is removed, the entries in that list will
never get cleaned. Fix this by flushing all corresponding items of the
preq_queue in mesh_path_flush_pending().

This should take care of KASAN reports like this:

unreferenced object 0xffff00000668d800 (size 128):
  comm "kworker/u8:4", pid 67, jiffies 4295419552 (age 1836.444s)
  hex dump (first 32 bytes):
    00 1f 05 09 00 00 ff ff 00 d5 68 06 00 00 ff ff  ..........h.....
    8e 97 ea eb 3e b8 01 00 00 00 00 00 00 00 00 00  ....>...........
  backtrace:
    [<000000007302a0b6>] __kmem_cache_alloc_node+0x1e0/0x35c
    [<00000000049bd418>] kmalloc_trace+0x34/0x80
    [<0000000000d792bb>] mesh_queue_preq+0x44/0x2a8
    [<00000000c99c3696>] mesh_nexthop_resolve+0x198/0x19c
    [<00000000926bf598>] ieee80211_xmit+0x1d0/0x1f4
    [<00000000fc8c2284>] __ieee80211_subif_start_xmit+0x30c/0x764
    [<000000005926ee38>] ieee80211_subif_start_xmit+0x9c/0x7a4
    [<000000004c86e916>] dev_hard_start_xmit+0x174/0x440
    [<0000000023495647>] __dev_queue_xmit+0xe24/0x111c
    [<00000000cfe9ca78>] batadv_send_skb_packet+0x180/0x1e4
    [<000000007bacc5d5>] batadv_v_elp_periodic_work+0x2f4/0x508
    [<00000000adc3cd94>] process_one_work+0x4b8/0xa1c
    [<00000000b36425d1>] worker_thread+0x9c/0x634
    [<0000000005852dd5>] kthread+0x1bc/0x1c4
    [<000000005fccd770>] ret_from_fork+0x10/0x20
unreferenced object 0xffff000009051f00 (size 128):
  comm "kworker/u8:4", pid 67, jiffies 4295419553 (age 1836.440s)
  hex dump (first 32 bytes):
    90 d6 92 0d 00 00 ff ff 00 d8 68 06 00 00 ff ff  ..........h.....
    36 27 92 e4 02 e0 01 00 00 58 79 06 00 00 ff ff  6'.......Xy.....
  backtrace:
    [<000000007302a0b6>] __kmem_cache_alloc_node+0x1e0/0x35c
    [<00000000049bd418>] kmalloc_trace+0x34/0x80
    [<0000000000d792bb>] mesh_queue_preq+0x44/0x2a8
    [<00000000c99c3696>] mesh_nexthop_resolve+0x198/0x19c
    [<00000000926bf598>] ieee80211_xmit+0x1d0/0x1f4
    [<00000000fc8c2284>] __ieee80211_subif_start_xmit+0x30c/0x764
    [<000000005926ee38>] ieee80211_subif_start_xmit+0x9c/0x7a4
    [<000000004c86e916>] dev_hard_start_xmit+0x174/0x440
    [<0000000023495647>] __dev_queue_xmit+0xe24/0x111c
    [<00000000cfe9ca78>] batadv_send_skb_packet+0x180/0x1e4
    [<000000007bacc5d5>] batadv_v_elp_periodic_work+0x2f4/0x508
    [<00000000adc3cd94>] process_one_work+0x4b8/0xa1c
    [<00000000b36425d1>] worker_thread+0x9c/0x634
    [<0000000005852dd5>] kthread+0x1bc/0x1c4
    [<000000005fccd770>] ret_from_fork+0x10/0x20

Fixes: 050ac52cbe ("mac80211: code for on-demand Hybrid Wireless Mesh Protocol")
Signed-off-by: Nicolas Escande <nico.escande@gmail.com>
Link: https://msgid.link/20240528142605.1060566-1-nico.escande@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-05-29 15:17:03 +02:00

1101 lines
30 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2008, 2009 open80211s Ltd.
* Copyright (C) 2023 Intel Corporation
* Author: Luis Carlos Cobo <luisca@cozybit.com>
*/
#include <linux/etherdevice.h>
#include <linux/list.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <net/mac80211.h>
#include "wme.h"
#include "ieee80211_i.h"
#include "mesh.h"
#include <linux/rhashtable.h>
static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath);
static u32 mesh_table_hash(const void *addr, u32 len, u32 seed)
{
/* Use last four bytes of hw addr as hash index */
return jhash_1word(__get_unaligned_cpu32((u8 *)addr + 2), seed);
}
static const struct rhashtable_params mesh_rht_params = {
.nelem_hint = 2,
.automatic_shrinking = true,
.key_len = ETH_ALEN,
.key_offset = offsetof(struct mesh_path, dst),
.head_offset = offsetof(struct mesh_path, rhash),
.hashfn = mesh_table_hash,
};
static const struct rhashtable_params fast_tx_rht_params = {
.nelem_hint = 10,
.automatic_shrinking = true,
.key_len = sizeof_field(struct ieee80211_mesh_fast_tx, key),
.key_offset = offsetof(struct ieee80211_mesh_fast_tx, key),
.head_offset = offsetof(struct ieee80211_mesh_fast_tx, rhash),
.hashfn = mesh_table_hash,
};
static void __mesh_fast_tx_entry_free(void *ptr, void *tblptr)
{
struct ieee80211_mesh_fast_tx *entry = ptr;
kfree_rcu(entry, fast_tx.rcu_head);
}
static void mesh_fast_tx_deinit(struct ieee80211_sub_if_data *sdata)
{
struct mesh_tx_cache *cache;
cache = &sdata->u.mesh.tx_cache;
rhashtable_free_and_destroy(&cache->rht,
__mesh_fast_tx_entry_free, NULL);
}
static void mesh_fast_tx_init(struct ieee80211_sub_if_data *sdata)
{
struct mesh_tx_cache *cache;
cache = &sdata->u.mesh.tx_cache;
rhashtable_init(&cache->rht, &fast_tx_rht_params);
INIT_HLIST_HEAD(&cache->walk_head);
spin_lock_init(&cache->walk_lock);
}
static inline bool mpath_expired(struct mesh_path *mpath)
{
return (mpath->flags & MESH_PATH_ACTIVE) &&
time_after(jiffies, mpath->exp_time) &&
!(mpath->flags & MESH_PATH_FIXED);
}
static void mesh_path_rht_free(void *ptr, void *tblptr)
{
struct mesh_path *mpath = ptr;
struct mesh_table *tbl = tblptr;
mesh_path_free_rcu(tbl, mpath);
}
static void mesh_table_init(struct mesh_table *tbl)
{
INIT_HLIST_HEAD(&tbl->known_gates);
INIT_HLIST_HEAD(&tbl->walk_head);
atomic_set(&tbl->entries, 0);
spin_lock_init(&tbl->gates_lock);
spin_lock_init(&tbl->walk_lock);
/* rhashtable_init() may fail only in case of wrong
* mesh_rht_params
*/
WARN_ON(rhashtable_init(&tbl->rhead, &mesh_rht_params));
}
static void mesh_table_free(struct mesh_table *tbl)
{
rhashtable_free_and_destroy(&tbl->rhead,
mesh_path_rht_free, tbl);
}
/**
* mesh_path_assign_nexthop - update mesh path next hop
*
* @mpath: mesh path to update
* @sta: next hop to assign
*
* Locking: mpath->state_lock must be held when calling this function
*/
void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
{
struct sk_buff *skb;
struct ieee80211_hdr *hdr;
unsigned long flags;
rcu_assign_pointer(mpath->next_hop, sta);
spin_lock_irqsave(&mpath->frame_queue.lock, flags);
skb_queue_walk(&mpath->frame_queue, skb) {
hdr = (struct ieee80211_hdr *) skb->data;
memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr);
}
spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
}
static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
struct mesh_path *gate_mpath)
{
struct ieee80211_hdr *hdr;
struct ieee80211s_hdr *mshdr;
int mesh_hdrlen, hdrlen;
char *next_hop;
hdr = (struct ieee80211_hdr *) skb->data;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
if (!(mshdr->flags & MESH_FLAGS_AE)) {
/* size of the fixed part of the mesh header */
mesh_hdrlen = 6;
/* make room for the two extended addresses */
skb_push(skb, 2 * ETH_ALEN);
memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
hdr = (struct ieee80211_hdr *) skb->data;
/* we preserve the previous mesh header and only add
* the new addresses */
mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
mshdr->flags = MESH_FLAGS_AE_A5_A6;
memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
}
/* update next hop */
hdr = (struct ieee80211_hdr *) skb->data;
rcu_read_lock();
next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
memcpy(hdr->addr1, next_hop, ETH_ALEN);
rcu_read_unlock();
memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
memcpy(hdr->addr3, dst_addr, ETH_ALEN);
}
/**
* mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
*
* @gate_mpath: An active mpath the frames will be sent to (i.e. the gate)
* @from_mpath: The failed mpath
* @copy: When true, copy all the frames to the new mpath queue. When false,
* move them.
*
* This function is used to transfer or copy frames from an unresolved mpath to
* a gate mpath. The function also adds the Address Extension field and
* updates the next hop.
*
* If a frame already has an Address Extension field, only the next hop and
* destination addresses are updated.
*
* The gate mpath must be an active mpath with a valid mpath->next_hop.
*/
static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
struct mesh_path *from_mpath,
bool copy)
{
struct sk_buff *skb, *fskb, *tmp;
struct sk_buff_head failq;
unsigned long flags;
if (WARN_ON(gate_mpath == from_mpath))
return;
if (WARN_ON(!gate_mpath->next_hop))
return;
__skb_queue_head_init(&failq);
spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
skb_queue_splice_init(&from_mpath->frame_queue, &failq);
spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
skb_queue_walk_safe(&failq, fskb, tmp) {
if (skb_queue_len(&gate_mpath->frame_queue) >=
MESH_FRAME_QUEUE_LEN) {
mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
break;
}
skb = skb_copy(fskb, GFP_ATOMIC);
if (WARN_ON(!skb))
break;
prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
skb_queue_tail(&gate_mpath->frame_queue, skb);
if (copy)
continue;
__skb_unlink(fskb, &failq);
kfree_skb(fskb);
}
mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
if (!copy)
return;
spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
skb_queue_splice(&failq, &from_mpath->frame_queue);
spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
}
static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
struct ieee80211_sub_if_data *sdata)
{
struct mesh_path *mpath;
mpath = rhashtable_lookup(&tbl->rhead, dst, mesh_rht_params);
if (mpath && mpath_expired(mpath)) {
spin_lock_bh(&mpath->state_lock);
mpath->flags &= ~MESH_PATH_ACTIVE;
spin_unlock_bh(&mpath->state_lock);
}
return mpath;
}
/**
* mesh_path_lookup - look up a path in the mesh path table
* @sdata: local subif
* @dst: hardware address (ETH_ALEN length) of destination
*
* Returns: pointer to the mesh path structure, or NULL if not found
*
* Locking: must be called within a read rcu section.
*/
struct mesh_path *
mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
{
return mpath_lookup(&sdata->u.mesh.mesh_paths, dst, sdata);
}
struct mesh_path *
mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
{
return mpath_lookup(&sdata->u.mesh.mpp_paths, dst, sdata);
}
static struct mesh_path *
__mesh_path_lookup_by_idx(struct mesh_table *tbl, int idx)
{
int i = 0;
struct mesh_path *mpath;
hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) {
if (i++ == idx)
break;
}
if (!mpath)
return NULL;
if (mpath_expired(mpath)) {
spin_lock_bh(&mpath->state_lock);
mpath->flags &= ~MESH_PATH_ACTIVE;
spin_unlock_bh(&mpath->state_lock);
}
return mpath;
}
/**
* mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
* @idx: index
* @sdata: local subif, or NULL for all entries
*
* Returns: pointer to the mesh path structure, or NULL if not found.
*
* Locking: must be called within a read rcu section.
*/
struct mesh_path *
mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
{
return __mesh_path_lookup_by_idx(&sdata->u.mesh.mesh_paths, idx);
}
/**
* mpp_path_lookup_by_idx - look up a path in the proxy path table by its index
* @idx: index
* @sdata: local subif, or NULL for all entries
*
* Returns: pointer to the proxy path structure, or NULL if not found.
*
* Locking: must be called within a read rcu section.
*/
struct mesh_path *
mpp_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
{
return __mesh_path_lookup_by_idx(&sdata->u.mesh.mpp_paths, idx);
}
/**
* mesh_path_add_gate - add the given mpath to a mesh gate to our path table
* @mpath: gate path to add to table
*
* Returns: 0 on success, -EEXIST
*/
int mesh_path_add_gate(struct mesh_path *mpath)
{
struct mesh_table *tbl;
int err;
rcu_read_lock();
tbl = &mpath->sdata->u.mesh.mesh_paths;
spin_lock_bh(&mpath->state_lock);
if (mpath->is_gate) {
err = -EEXIST;
spin_unlock_bh(&mpath->state_lock);
goto err_rcu;
}
mpath->is_gate = true;
mpath->sdata->u.mesh.num_gates++;
spin_lock(&tbl->gates_lock);
hlist_add_head_rcu(&mpath->gate_list, &tbl->known_gates);
spin_unlock(&tbl->gates_lock);
spin_unlock_bh(&mpath->state_lock);
mpath_dbg(mpath->sdata,
"Mesh path: Recorded new gate: %pM. %d known gates\n",
mpath->dst, mpath->sdata->u.mesh.num_gates);
err = 0;
err_rcu:
rcu_read_unlock();
return err;
}
/**
* mesh_gate_del - remove a mesh gate from the list of known gates
* @tbl: table which holds our list of known gates
* @mpath: gate mpath
*/
static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
{
lockdep_assert_held(&mpath->state_lock);
if (!mpath->is_gate)
return;
mpath->is_gate = false;
spin_lock_bh(&tbl->gates_lock);
hlist_del_rcu(&mpath->gate_list);
mpath->sdata->u.mesh.num_gates--;
spin_unlock_bh(&tbl->gates_lock);
mpath_dbg(mpath->sdata,
"Mesh path: Deleted gate: %pM. %d known gates\n",
mpath->dst, mpath->sdata->u.mesh.num_gates);
}
/**
* mesh_gate_num - number of gates known to this interface
* @sdata: subif data
*
* Returns: The number of gates
*/
int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
{
return sdata->u.mesh.num_gates;
}
static
struct mesh_path *mesh_path_new(struct ieee80211_sub_if_data *sdata,
const u8 *dst, gfp_t gfp_flags)
{
struct mesh_path *new_mpath;
new_mpath = kzalloc(sizeof(struct mesh_path), gfp_flags);
if (!new_mpath)
return NULL;
memcpy(new_mpath->dst, dst, ETH_ALEN);
eth_broadcast_addr(new_mpath->rann_snd_addr);
new_mpath->is_root = false;
new_mpath->sdata = sdata;
new_mpath->flags = 0;
skb_queue_head_init(&new_mpath->frame_queue);
new_mpath->exp_time = jiffies;
spin_lock_init(&new_mpath->state_lock);
timer_setup(&new_mpath->timer, mesh_path_timer, 0);
return new_mpath;
}
static void mesh_fast_tx_entry_free(struct mesh_tx_cache *cache,
struct ieee80211_mesh_fast_tx *entry)
{
hlist_del_rcu(&entry->walk_list);
rhashtable_remove_fast(&cache->rht, &entry->rhash, fast_tx_rht_params);
kfree_rcu(entry, fast_tx.rcu_head);
}
struct ieee80211_mesh_fast_tx *
mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mesh_fast_tx_key *key)
{
struct ieee80211_mesh_fast_tx *entry;
struct mesh_tx_cache *cache;
cache = &sdata->u.mesh.tx_cache;
entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params);
if (!entry)
return NULL;
if (!(entry->mpath->flags & MESH_PATH_ACTIVE) ||
mpath_expired(entry->mpath)) {
spin_lock_bh(&cache->walk_lock);
entry = rhashtable_lookup(&cache->rht, key, fast_tx_rht_params);
if (entry)
mesh_fast_tx_entry_free(cache, entry);
spin_unlock_bh(&cache->walk_lock);
return NULL;
}
mesh_path_refresh(sdata, entry->mpath, NULL);
if (entry->mppath)
entry->mppath->exp_time = jiffies;
entry->timestamp = jiffies;
return entry;
}
void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb, struct mesh_path *mpath)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_mesh_fast_tx *entry, *prev;
struct ieee80211_mesh_fast_tx build = {};
struct ieee80211s_hdr *meshhdr;
struct mesh_tx_cache *cache;
struct ieee80211_key *key;
struct mesh_path *mppath;
struct sta_info *sta;
u8 *qc;
if (sdata->noack_map ||
!ieee80211_is_data_qos(hdr->frame_control))
return;
build.fast_tx.hdr_len = ieee80211_hdrlen(hdr->frame_control);
meshhdr = (struct ieee80211s_hdr *)(skb->data + build.fast_tx.hdr_len);
build.hdrlen = ieee80211_get_mesh_hdrlen(meshhdr);
cache = &sdata->u.mesh.tx_cache;
if (atomic_read(&cache->rht.nelems) >= MESH_FAST_TX_CACHE_MAX_SIZE)
return;
sta = rcu_dereference(mpath->next_hop);
if (!sta)
return;
build.key.type = MESH_FAST_TX_TYPE_LOCAL;
if ((meshhdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6) {
/* This is required to keep the mppath alive */
mppath = mpp_path_lookup(sdata, meshhdr->eaddr1);
if (!mppath)
return;
build.mppath = mppath;
if (!ether_addr_equal(meshhdr->eaddr2, sdata->vif.addr))
build.key.type = MESH_FAST_TX_TYPE_PROXIED;
} else if (ieee80211_has_a4(hdr->frame_control)) {
mppath = mpath;
} else {
return;
}
if (!ether_addr_equal(hdr->addr4, sdata->vif.addr))
build.key.type = MESH_FAST_TX_TYPE_FORWARDED;
/* rate limit, in case fast xmit can't be enabled */
if (mppath->fast_tx_check == jiffies)
return;
mppath->fast_tx_check = jiffies;
/*
* Same use of the sta lock as in ieee80211_check_fast_xmit, in order
* to protect against concurrent sta key updates.
*/
spin_lock_bh(&sta->lock);
key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
if (!key)
key = rcu_access_pointer(sdata->default_unicast_key);
build.fast_tx.key = key;
if (key) {
bool gen_iv, iv_spc;
gen_iv = key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
iv_spc = key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) ||
(key->flags & KEY_FLAG_TAINTED))
goto unlock_sta;
switch (key->conf.cipher) {
case WLAN_CIPHER_SUITE_CCMP:
case WLAN_CIPHER_SUITE_CCMP_256:
if (gen_iv)
build.fast_tx.pn_offs = build.fast_tx.hdr_len;
if (gen_iv || iv_spc)
build.fast_tx.hdr_len += IEEE80211_CCMP_HDR_LEN;
break;
case WLAN_CIPHER_SUITE_GCMP:
case WLAN_CIPHER_SUITE_GCMP_256:
if (gen_iv)
build.fast_tx.pn_offs = build.fast_tx.hdr_len;
if (gen_iv || iv_spc)
build.fast_tx.hdr_len += IEEE80211_GCMP_HDR_LEN;
break;
default:
goto unlock_sta;
}
}
memcpy(build.key.addr, mppath->dst, ETH_ALEN);
build.timestamp = jiffies;
build.fast_tx.band = info->band;
build.fast_tx.da_offs = offsetof(struct ieee80211_hdr, addr3);
build.fast_tx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
build.mpath = mpath;
memcpy(build.hdr, meshhdr, build.hdrlen);
memcpy(build.hdr + build.hdrlen, rfc1042_header, sizeof(rfc1042_header));
build.hdrlen += sizeof(rfc1042_header);
memcpy(build.fast_tx.hdr, hdr, build.fast_tx.hdr_len);
hdr = (struct ieee80211_hdr *)build.fast_tx.hdr;
if (build.fast_tx.key)
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
qc = ieee80211_get_qos_ctl(hdr);
qc[1] |= IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8;
entry = kmemdup(&build, sizeof(build), GFP_ATOMIC);
if (!entry)
goto unlock_sta;
spin_lock(&cache->walk_lock);
prev = rhashtable_lookup_get_insert_fast(&cache->rht,
&entry->rhash,
fast_tx_rht_params);
if (unlikely(IS_ERR(prev))) {
kfree(entry);
goto unlock_cache;
}
/*
* replace any previous entry in the hash table, in case we're
* replacing it with a different type (e.g. mpath -> mpp)
*/
if (unlikely(prev)) {
rhashtable_replace_fast(&cache->rht, &prev->rhash,
&entry->rhash, fast_tx_rht_params);
hlist_del_rcu(&prev->walk_list);
kfree_rcu(prev, fast_tx.rcu_head);
}
hlist_add_head(&entry->walk_list, &cache->walk_head);
unlock_cache:
spin_unlock(&cache->walk_lock);
unlock_sta:
spin_unlock_bh(&sta->lock);
}
void mesh_fast_tx_gc(struct ieee80211_sub_if_data *sdata)
{
unsigned long timeout = msecs_to_jiffies(MESH_FAST_TX_CACHE_TIMEOUT);
struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
struct ieee80211_mesh_fast_tx *entry;
struct hlist_node *n;
if (atomic_read(&cache->rht.nelems) < MESH_FAST_TX_CACHE_THRESHOLD_SIZE)
return;
spin_lock_bh(&cache->walk_lock);
hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
if (!time_is_after_jiffies(entry->timestamp + timeout))
mesh_fast_tx_entry_free(cache, entry);
spin_unlock_bh(&cache->walk_lock);
}
void mesh_fast_tx_flush_mpath(struct mesh_path *mpath)
{
struct ieee80211_sub_if_data *sdata = mpath->sdata;
struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
struct ieee80211_mesh_fast_tx *entry;
struct hlist_node *n;
spin_lock_bh(&cache->walk_lock);
hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
if (entry->mpath == mpath)
mesh_fast_tx_entry_free(cache, entry);
spin_unlock_bh(&cache->walk_lock);
}
void mesh_fast_tx_flush_sta(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta)
{
struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
struct ieee80211_mesh_fast_tx *entry;
struct hlist_node *n;
spin_lock_bh(&cache->walk_lock);
hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
if (rcu_access_pointer(entry->mpath->next_hop) == sta)
mesh_fast_tx_entry_free(cache, entry);
spin_unlock_bh(&cache->walk_lock);
}
void mesh_fast_tx_flush_addr(struct ieee80211_sub_if_data *sdata,
const u8 *addr)
{
struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
struct ieee80211_mesh_fast_tx_key key = {};
struct ieee80211_mesh_fast_tx *entry;
int i;
ether_addr_copy(key.addr, addr);
spin_lock_bh(&cache->walk_lock);
for (i = 0; i < NUM_MESH_FAST_TX_TYPE; i++) {
key.type = i;
entry = rhashtable_lookup_fast(&cache->rht, &key, fast_tx_rht_params);
if (entry)
mesh_fast_tx_entry_free(cache, entry);
}
spin_unlock_bh(&cache->walk_lock);
}
/**
* mesh_path_add - allocate and add a new path to the mesh path table
* @dst: destination address of the path (ETH_ALEN length)
* @sdata: local subif
*
* Returns: 0 on success
*
* State: the initial state of the new path is set to 0
*/
struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
const u8 *dst)
{
struct mesh_table *tbl;
struct mesh_path *mpath, *new_mpath;
if (ether_addr_equal(dst, sdata->vif.addr))
/* never add ourselves as neighbours */
return ERR_PTR(-EOPNOTSUPP);
if (is_multicast_ether_addr(dst))
return ERR_PTR(-EOPNOTSUPP);
if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
return ERR_PTR(-ENOSPC);
new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
if (!new_mpath)
return ERR_PTR(-ENOMEM);
tbl = &sdata->u.mesh.mesh_paths;
spin_lock_bh(&tbl->walk_lock);
mpath = rhashtable_lookup_get_insert_fast(&tbl->rhead,
&new_mpath->rhash,
mesh_rht_params);
if (!mpath)
hlist_add_head(&new_mpath->walk_list, &tbl->walk_head);
spin_unlock_bh(&tbl->walk_lock);
if (mpath) {
kfree(new_mpath);
if (IS_ERR(mpath))
return mpath;
new_mpath = mpath;
}
sdata->u.mesh.mesh_paths_generation++;
return new_mpath;
}
int mpp_path_add(struct ieee80211_sub_if_data *sdata,
const u8 *dst, const u8 *mpp)
{
struct mesh_table *tbl;
struct mesh_path *new_mpath;
int ret;
if (ether_addr_equal(dst, sdata->vif.addr))
/* never add ourselves as neighbours */
return -EOPNOTSUPP;
if (is_multicast_ether_addr(dst))
return -EOPNOTSUPP;
new_mpath = mesh_path_new(sdata, dst, GFP_ATOMIC);
if (!new_mpath)
return -ENOMEM;
memcpy(new_mpath->mpp, mpp, ETH_ALEN);
tbl = &sdata->u.mesh.mpp_paths;
spin_lock_bh(&tbl->walk_lock);
ret = rhashtable_lookup_insert_fast(&tbl->rhead,
&new_mpath->rhash,
mesh_rht_params);
if (!ret)
hlist_add_head_rcu(&new_mpath->walk_list, &tbl->walk_head);
spin_unlock_bh(&tbl->walk_lock);
if (ret)
kfree(new_mpath);
else
mesh_fast_tx_flush_addr(sdata, dst);
sdata->u.mesh.mpp_paths_generation++;
return ret;
}
/**
* mesh_plink_broken - deactivates paths and sends perr when a link breaks
*
* @sta: broken peer link
*
* This function must be called from the rate control algorithm if enough
* delivery errors suggest that a peer link is no longer usable.
*/
void mesh_plink_broken(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct mesh_table *tbl = &sdata->u.mesh.mesh_paths;
static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
struct mesh_path *mpath;
rcu_read_lock();
hlist_for_each_entry_rcu(mpath, &tbl->walk_head, walk_list) {
if (rcu_access_pointer(mpath->next_hop) == sta &&
mpath->flags & MESH_PATH_ACTIVE &&
!(mpath->flags & MESH_PATH_FIXED)) {
spin_lock_bh(&mpath->state_lock);
mpath->flags &= ~MESH_PATH_ACTIVE;
++mpath->sn;
spin_unlock_bh(&mpath->state_lock);
mesh_path_error_tx(sdata,
sdata->u.mesh.mshcfg.element_ttl,
mpath->dst, mpath->sn,
WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast);
}
}
rcu_read_unlock();
}
static void mesh_path_free_rcu(struct mesh_table *tbl,
struct mesh_path *mpath)
{
struct ieee80211_sub_if_data *sdata = mpath->sdata;
spin_lock_bh(&mpath->state_lock);
mpath->flags |= MESH_PATH_RESOLVING | MESH_PATH_DELETED;
mesh_gate_del(tbl, mpath);
spin_unlock_bh(&mpath->state_lock);
timer_shutdown_sync(&mpath->timer);
atomic_dec(&sdata->u.mesh.mpaths);
atomic_dec(&tbl->entries);
mesh_path_flush_pending(mpath);
kfree_rcu(mpath, rcu);
}
static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath)
{
hlist_del_rcu(&mpath->walk_list);
rhashtable_remove_fast(&tbl->rhead, &mpath->rhash, mesh_rht_params);
if (tbl == &mpath->sdata->u.mesh.mpp_paths)
mesh_fast_tx_flush_addr(mpath->sdata, mpath->dst);
else
mesh_fast_tx_flush_mpath(mpath);
mesh_path_free_rcu(tbl, mpath);
}
/**
* mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
*
* @sta: mesh peer to match
*
* RCU notes: this function is called when a mesh plink transitions from
* PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
* allows path creation. This will happen before the sta can be freed (because
* sta_info_destroy() calls this) so any reader in a rcu read block will be
* protected against the plink disappearing.
*/
void mesh_path_flush_by_nexthop(struct sta_info *sta)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct mesh_table *tbl = &sdata->u.mesh.mesh_paths;
struct mesh_path *mpath;
struct hlist_node *n;
spin_lock_bh(&tbl->walk_lock);
hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
if (rcu_access_pointer(mpath->next_hop) == sta)
__mesh_path_del(tbl, mpath);
}
spin_unlock_bh(&tbl->walk_lock);
}
static void mpp_flush_by_proxy(struct ieee80211_sub_if_data *sdata,
const u8 *proxy)
{
struct mesh_table *tbl = &sdata->u.mesh.mpp_paths;
struct mesh_path *mpath;
struct hlist_node *n;
spin_lock_bh(&tbl->walk_lock);
hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
if (ether_addr_equal(mpath->mpp, proxy))
__mesh_path_del(tbl, mpath);
}
spin_unlock_bh(&tbl->walk_lock);
}
static void table_flush_by_iface(struct mesh_table *tbl)
{
struct mesh_path *mpath;
struct hlist_node *n;
spin_lock_bh(&tbl->walk_lock);
hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
__mesh_path_del(tbl, mpath);
}
spin_unlock_bh(&tbl->walk_lock);
}
/**
* mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
*
* @sdata: interface data to match
*
* This function deletes both mesh paths as well as mesh portal paths.
*/
void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
{
table_flush_by_iface(&sdata->u.mesh.mesh_paths);
table_flush_by_iface(&sdata->u.mesh.mpp_paths);
}
/**
* table_path_del - delete a path from the mesh or mpp table
*
* @tbl: mesh or mpp path table
* @sdata: local subif
* @addr: dst address (ETH_ALEN length)
*
* Returns: 0 if successful
*/
static int table_path_del(struct mesh_table *tbl,
struct ieee80211_sub_if_data *sdata,
const u8 *addr)
{
struct mesh_path *mpath;
spin_lock_bh(&tbl->walk_lock);
mpath = rhashtable_lookup_fast(&tbl->rhead, addr, mesh_rht_params);
if (!mpath) {
spin_unlock_bh(&tbl->walk_lock);
return -ENXIO;
}
__mesh_path_del(tbl, mpath);
spin_unlock_bh(&tbl->walk_lock);
return 0;
}
/**
* mesh_path_del - delete a mesh path from the table
*
* @addr: dst address (ETH_ALEN length)
* @sdata: local subif
*
* Returns: 0 if successful
*/
int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
{
int err;
/* flush relevant mpp entries first */
mpp_flush_by_proxy(sdata, addr);
err = table_path_del(&sdata->u.mesh.mesh_paths, sdata, addr);
sdata->u.mesh.mesh_paths_generation++;
return err;
}
/**
* mesh_path_tx_pending - sends pending frames in a mesh path queue
*
* @mpath: mesh path to activate
*
* Locking: the state_lock of the mpath structure must NOT be held when calling
* this function.
*/
void mesh_path_tx_pending(struct mesh_path *mpath)
{
if (mpath->flags & MESH_PATH_ACTIVE)
ieee80211_add_pending_skbs(mpath->sdata->local,
&mpath->frame_queue);
}
/**
* mesh_path_send_to_gates - sends pending frames to all known mesh gates
*
* @mpath: mesh path whose queue will be emptied
*
* If there is only one gate, the frames are transferred from the failed mpath
* queue to that gate's queue. If there are more than one gates, the frames
* are copied from each gate to the next. After frames are copied, the
* mpath queues are emptied onto the transmission queue.
*
* Returns: 0 on success, -EHOSTUNREACH
*/
int mesh_path_send_to_gates(struct mesh_path *mpath)
{
struct ieee80211_sub_if_data *sdata = mpath->sdata;
struct mesh_table *tbl;
struct mesh_path *from_mpath = mpath;
struct mesh_path *gate;
bool copy = false;
tbl = &sdata->u.mesh.mesh_paths;
rcu_read_lock();
hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
if (gate->flags & MESH_PATH_ACTIVE) {
mpath_dbg(sdata, "Forwarding to %pM\n", gate->dst);
mesh_path_move_to_queue(gate, from_mpath, copy);
from_mpath = gate;
copy = true;
} else {
mpath_dbg(sdata,
"Not forwarding to %pM (flags %#x)\n",
gate->dst, gate->flags);
}
}
hlist_for_each_entry_rcu(gate, &tbl->known_gates, gate_list) {
mpath_dbg(sdata, "Sending to %pM\n", gate->dst);
mesh_path_tx_pending(gate);
}
rcu_read_unlock();
return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
}
/**
* mesh_path_discard_frame - discard a frame whose path could not be resolved
*
* @skb: frame to discard
* @sdata: network subif the frame was to be sent through
*
* Locking: the function must me called within a rcu_read_lock region
*/
void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
ieee80211_free_txskb(&sdata->local->hw, skb);
sdata->u.mesh.mshstats.dropped_frames_no_route++;
}
/**
* mesh_path_flush_pending - free the pending queue of a mesh path
*
* @mpath: mesh path whose queue has to be freed
*
* Locking: the function must me called within a rcu_read_lock region
*/
void mesh_path_flush_pending(struct mesh_path *mpath)
{
struct ieee80211_sub_if_data *sdata = mpath->sdata;
struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
struct mesh_preq_queue *preq, *tmp;
struct sk_buff *skb;
while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
mesh_path_discard_frame(mpath->sdata, skb);
spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
list_for_each_entry_safe(preq, tmp, &ifmsh->preq_queue.list, list) {
if (ether_addr_equal(mpath->dst, preq->dst)) {
list_del(&preq->list);
kfree(preq);
--ifmsh->preq_queue_len;
}
}
spin_unlock_bh(&ifmsh->mesh_preq_queue_lock);
}
/**
* mesh_path_fix_nexthop - force a specific next hop for a mesh path
*
* @mpath: the mesh path to modify
* @next_hop: the next hop to force
*
* Locking: this function must be called holding mpath->state_lock
*/
void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
{
spin_lock_bh(&mpath->state_lock);
mesh_path_assign_nexthop(mpath, next_hop);
mpath->sn = 0xffff;
mpath->metric = 0;
mpath->hop_count = 0;
mpath->exp_time = 0;
mpath->flags = MESH_PATH_FIXED | MESH_PATH_SN_VALID;
mesh_path_activate(mpath);
mesh_fast_tx_flush_mpath(mpath);
spin_unlock_bh(&mpath->state_lock);
ewma_mesh_fail_avg_init(&next_hop->mesh->fail_avg);
/* init it at a low value - 0 start is tricky */
ewma_mesh_fail_avg_add(&next_hop->mesh->fail_avg, 1);
mesh_path_tx_pending(mpath);
}
void mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata)
{
mesh_table_init(&sdata->u.mesh.mesh_paths);
mesh_table_init(&sdata->u.mesh.mpp_paths);
mesh_fast_tx_init(sdata);
}
static
void mesh_path_tbl_expire(struct ieee80211_sub_if_data *sdata,
struct mesh_table *tbl)
{
struct mesh_path *mpath;
struct hlist_node *n;
spin_lock_bh(&tbl->walk_lock);
hlist_for_each_entry_safe(mpath, n, &tbl->walk_head, walk_list) {
if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
(!(mpath->flags & MESH_PATH_FIXED)) &&
time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
__mesh_path_del(tbl, mpath);
}
spin_unlock_bh(&tbl->walk_lock);
}
void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
{
mesh_path_tbl_expire(sdata, &sdata->u.mesh.mesh_paths);
mesh_path_tbl_expire(sdata, &sdata->u.mesh.mpp_paths);
}
void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata)
{
mesh_fast_tx_deinit(sdata);
mesh_table_free(&sdata->u.mesh.mesh_paths);
mesh_table_free(&sdata->u.mesh.mpp_paths);
}