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path: root/net/batman-adv/bridge_loop_avoidance.c
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Diffstat (limited to 'net/batman-adv/bridge_loop_avoidance.c')
-rw-r--r--net/batman-adv/bridge_loop_avoidance.c116
1 files changed, 92 insertions, 24 deletions
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 748a9ead7ce5..825a5cdf4382 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -177,10 +177,21 @@ static void batadv_backbone_gw_put(struct batadv_bla_backbone_gw *backbone_gw)
static void batadv_claim_release(struct kref *ref)
{
struct batadv_bla_claim *claim;
+ struct batadv_bla_backbone_gw *old_backbone_gw;
claim = container_of(ref, struct batadv_bla_claim, refcount);
- batadv_backbone_gw_put(claim->backbone_gw);
+ spin_lock_bh(&claim->backbone_lock);
+ old_backbone_gw = claim->backbone_gw;
+ claim->backbone_gw = NULL;
+ spin_unlock_bh(&claim->backbone_lock);
+
+ spin_lock_bh(&old_backbone_gw->crc_lock);
+ old_backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
+ spin_unlock_bh(&old_backbone_gw->crc_lock);
+
+ batadv_backbone_gw_put(old_backbone_gw);
+
kfree_rcu(claim, rcu);
}
@@ -418,9 +429,12 @@ static void batadv_bla_send_claim(struct batadv_priv *bat_priv, u8 *mac,
break;
}
- if (vid & BATADV_VLAN_HAS_TAG)
+ if (vid & BATADV_VLAN_HAS_TAG) {
skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
vid & VLAN_VID_MASK);
+ if (!skb)
+ goto out;
+ }
skb_reset_mac_header(skb);
skb->protocol = eth_type_trans(skb, soft_iface);
@@ -674,8 +688,10 @@ static void batadv_bla_add_claim(struct batadv_priv *bat_priv,
const u8 *mac, const unsigned short vid,
struct batadv_bla_backbone_gw *backbone_gw)
{
+ struct batadv_bla_backbone_gw *old_backbone_gw;
struct batadv_bla_claim *claim;
struct batadv_bla_claim search_claim;
+ bool remove_crc = false;
int hash_added;
ether_addr_copy(search_claim.addr, mac);
@@ -689,8 +705,10 @@ static void batadv_bla_add_claim(struct batadv_priv *bat_priv,
return;
ether_addr_copy(claim->addr, mac);
+ spin_lock_init(&claim->backbone_lock);
claim->vid = vid;
claim->lasttime = jiffies;
+ kref_get(&backbone_gw->refcount);
claim->backbone_gw = backbone_gw;
kref_init(&claim->refcount);
@@ -718,15 +736,26 @@ static void batadv_bla_add_claim(struct batadv_priv *bat_priv,
"bla_add_claim(): changing ownership for %pM, vid %d\n",
mac, BATADV_PRINT_VID(vid));
- spin_lock_bh(&claim->backbone_gw->crc_lock);
- claim->backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
- spin_unlock_bh(&claim->backbone_gw->crc_lock);
- batadv_backbone_gw_put(claim->backbone_gw);
+ remove_crc = true;
}
- /* set (new) backbone gw */
+
+ /* replace backbone_gw atomically and adjust reference counters */
+ spin_lock_bh(&claim->backbone_lock);
+ old_backbone_gw = claim->backbone_gw;
kref_get(&backbone_gw->refcount);
claim->backbone_gw = backbone_gw;
+ spin_unlock_bh(&claim->backbone_lock);
+ if (remove_crc) {
+ /* remove claim address from old backbone_gw */
+ spin_lock_bh(&old_backbone_gw->crc_lock);
+ old_backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
+ spin_unlock_bh(&old_backbone_gw->crc_lock);
+ }
+
+ batadv_backbone_gw_put(old_backbone_gw);
+
+ /* add claim address to new backbone_gw */
spin_lock_bh(&backbone_gw->crc_lock);
backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
spin_unlock_bh(&backbone_gw->crc_lock);
@@ -737,6 +766,26 @@ claim_free_ref:
}
/**
+ * batadv_bla_claim_get_backbone_gw - Get valid reference for backbone_gw of
+ * claim
+ * @claim: claim whose backbone_gw should be returned
+ *
+ * Return: valid reference to claim::backbone_gw
+ */
+static struct batadv_bla_backbone_gw *
+batadv_bla_claim_get_backbone_gw(struct batadv_bla_claim *claim)
+{
+ struct batadv_bla_backbone_gw *backbone_gw;
+
+ spin_lock_bh(&claim->backbone_lock);
+ backbone_gw = claim->backbone_gw;
+ kref_get(&backbone_gw->refcount);
+ spin_unlock_bh(&claim->backbone_lock);
+
+ return backbone_gw;
+}
+
+/**
* batadv_bla_del_claim - delete a claim from the claim hash
* @bat_priv: the bat priv with all the soft interface information
* @mac: mac address of the claim to be removed
@@ -760,10 +809,6 @@ static void batadv_bla_del_claim(struct batadv_priv *bat_priv,
batadv_choose_claim, claim);
batadv_claim_put(claim); /* reference from the hash is gone */
- spin_lock_bh(&claim->backbone_gw->crc_lock);
- claim->backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
- spin_unlock_bh(&claim->backbone_gw->crc_lock);
-
/* don't need the reference from hash_find() anymore */
batadv_claim_put(claim);
}
@@ -1216,6 +1261,7 @@ static void batadv_bla_purge_claims(struct batadv_priv *bat_priv,
struct batadv_hard_iface *primary_if,
int now)
{
+ struct batadv_bla_backbone_gw *backbone_gw;
struct batadv_bla_claim *claim;
struct hlist_head *head;
struct batadv_hashtable *hash;
@@ -1230,14 +1276,17 @@ static void batadv_bla_purge_claims(struct batadv_priv *bat_priv,
rcu_read_lock();
hlist_for_each_entry_rcu(claim, head, hash_entry) {
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
if (now)
goto purge_now;
- if (!batadv_compare_eth(claim->backbone_gw->orig,
+
+ if (!batadv_compare_eth(backbone_gw->orig,
primary_if->net_dev->dev_addr))
- continue;
+ goto skip;
+
if (!batadv_has_timed_out(claim->lasttime,
BATADV_BLA_CLAIM_TIMEOUT))
- continue;
+ goto skip;
batadv_dbg(BATADV_DBG_BLA, bat_priv,
"bla_purge_claims(): %pM, vid %d, time out\n",
@@ -1245,8 +1294,10 @@ static void batadv_bla_purge_claims(struct batadv_priv *bat_priv,
purge_now:
batadv_handle_unclaim(bat_priv, primary_if,
- claim->backbone_gw->orig,
+ backbone_gw->orig,
claim->addr, claim->vid);
+skip:
+ batadv_backbone_gw_put(backbone_gw);
}
rcu_read_unlock();
}
@@ -1757,9 +1808,11 @@ batadv_bla_loopdetect_check(struct batadv_priv *bat_priv, struct sk_buff *skb,
bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb,
unsigned short vid, bool is_bcast)
{
+ struct batadv_bla_backbone_gw *backbone_gw;
struct ethhdr *ethhdr;
struct batadv_bla_claim search_claim, *claim = NULL;
struct batadv_hard_iface *primary_if;
+ bool own_claim;
bool ret;
ethhdr = eth_hdr(skb);
@@ -1794,8 +1847,12 @@ bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb,
}
/* if it is our own claim ... */
- if (batadv_compare_eth(claim->backbone_gw->orig,
- primary_if->net_dev->dev_addr)) {
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
+ own_claim = batadv_compare_eth(backbone_gw->orig,
+ primary_if->net_dev->dev_addr);
+ batadv_backbone_gw_put(backbone_gw);
+
+ if (own_claim) {
/* ... allow it in any case */
claim->lasttime = jiffies;
goto allow;
@@ -1859,7 +1916,9 @@ bool batadv_bla_tx(struct batadv_priv *bat_priv, struct sk_buff *skb,
{
struct ethhdr *ethhdr;
struct batadv_bla_claim search_claim, *claim = NULL;
+ struct batadv_bla_backbone_gw *backbone_gw;
struct batadv_hard_iface *primary_if;
+ bool client_roamed;
bool ret = false;
primary_if = batadv_primary_if_get_selected(bat_priv);
@@ -1889,8 +1948,12 @@ bool batadv_bla_tx(struct batadv_priv *bat_priv, struct sk_buff *skb,
goto allow;
/* check if we are responsible. */
- if (batadv_compare_eth(claim->backbone_gw->orig,
- primary_if->net_dev->dev_addr)) {
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
+ client_roamed = batadv_compare_eth(backbone_gw->orig,
+ primary_if->net_dev->dev_addr);
+ batadv_backbone_gw_put(backbone_gw);
+
+ if (client_roamed) {
/* if yes, the client has roamed and we have
* to unclaim it.
*/
@@ -1938,6 +2001,7 @@ int batadv_bla_claim_table_seq_print_text(struct seq_file *seq, void *offset)
struct net_device *net_dev = (struct net_device *)seq->private;
struct batadv_priv *bat_priv = netdev_priv(net_dev);
struct batadv_hashtable *hash = bat_priv->bla.claim_hash;
+ struct batadv_bla_backbone_gw *backbone_gw;
struct batadv_bla_claim *claim;
struct batadv_hard_iface *primary_if;
struct hlist_head *head;
@@ -1962,17 +2026,21 @@ int batadv_bla_claim_table_seq_print_text(struct seq_file *seq, void *offset)
rcu_read_lock();
hlist_for_each_entry_rcu(claim, head, hash_entry) {
- is_own = batadv_compare_eth(claim->backbone_gw->orig,
+ backbone_gw = batadv_bla_claim_get_backbone_gw(claim);
+
+ is_own = batadv_compare_eth(backbone_gw->orig,
primary_addr);
- spin_lock_bh(&claim->backbone_gw->crc_lock);
- backbone_crc = claim->backbone_gw->crc;
- spin_unlock_bh(&claim->backbone_gw->crc_lock);
+ spin_lock_bh(&backbone_gw->crc_lock);
+ backbone_crc = backbone_gw->crc;
+ spin_unlock_bh(&backbone_gw->crc_lock);
seq_printf(seq, " * %pM on %5d by %pM [%c] (%#.4x)\n",
claim->addr, BATADV_PRINT_VID(claim->vid),
- claim->backbone_gw->orig,
+ backbone_gw->orig,
(is_own ? 'x' : ' '),
backbone_crc);
+
+ batadv_backbone_gw_put(backbone_gw);
}
rcu_read_unlock();
}
generated by cgit (git 2.34.1) at 2024-05-06 12:11:21 +0000