mac80211: fix AP_VLAN crypto tailroom calculation
Some splats I was seeing:
(a) WARNING: CPU: 1 PID: 0 at /devel/src/linux/net/mac80211/wep.c:102 ieee80211_wep_add_iv
(b) WARNING: CPU: 1 PID: 0 at /devel/src/linux/net/mac80211/wpa.c:73 ieee80211_tx_h_michael_mic_add
(c) WARNING: CPU: 3 PID: 0 at /devel/src/linux/net/mac80211/wpa.c:433 ieee80211_crypto_ccmp_encrypt
I've seen (a) and (b) with ath9k hw crypto and (c)
with ath9k sw crypto. All of them were related to
insufficient skb tailroom and I was able to
trigger these with ping6 program.
AP_VLANs may inherit crypto keys from parent AP.
This wasn't considered and yielded problems in
some setups resulting in inability to transmit
data because mac80211 wouldn't resize skbs when
necessary and subsequently drop some packets due
to insufficient tailroom.
For efficiency purposes don't inspect both AP_VLAN
and AP sdata looking for tailroom counter. Instead
update AP_VLAN tailroom counters whenever their
master AP tailroom counter changes.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index bab5c63..84cef60 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -522,6 +522,12 @@
memcpy(sdata->vif.hw_queue, master->vif.hw_queue,
sizeof(sdata->vif.hw_queue));
sdata->vif.bss_conf.chandef = master->vif.bss_conf.chandef;
+
+ mutex_lock(&local->key_mtx);
+ sdata->crypto_tx_tailroom_needed_cnt +=
+ master->crypto_tx_tailroom_needed_cnt;
+ mutex_unlock(&local->key_mtx);
+
break;
}
case NL80211_IFTYPE_AP:
diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 2291cd7..a907f2d 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -58,6 +58,22 @@
lockdep_assert_held(&local->key_mtx);
}
+static void
+update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
+{
+ struct ieee80211_sub_if_data *vlan;
+
+ if (sdata->vif.type != NL80211_IFTYPE_AP)
+ return;
+
+ mutex_lock(&sdata->local->mtx);
+
+ list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+ vlan->crypto_tx_tailroom_needed_cnt += delta;
+
+ mutex_unlock(&sdata->local->mtx);
+}
+
static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
{
/*
@@ -79,6 +95,8 @@
* http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
*/
+ update_vlan_tailroom_need_count(sdata, 1);
+
if (!sdata->crypto_tx_tailroom_needed_cnt++) {
/*
* Flush all XMIT packets currently using HW encryption or no
@@ -88,6 +106,15 @@
}
}
+static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
+ int delta)
+{
+ WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
+
+ update_vlan_tailroom_need_count(sdata, -delta);
+ sdata->crypto_tx_tailroom_needed_cnt -= delta;
+}
+
static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
{
struct ieee80211_sub_if_data *sdata;
@@ -144,7 +171,7 @@
if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
(key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
- sdata->crypto_tx_tailroom_needed_cnt--;
+ decrease_tailroom_need_count(sdata, 1);
WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
@@ -541,7 +568,7 @@
schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
HZ/2);
} else {
- sdata->crypto_tx_tailroom_needed_cnt--;
+ decrease_tailroom_need_count(sdata, 1);
}
}
@@ -631,6 +658,7 @@
void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_key *key;
+ struct ieee80211_sub_if_data *vlan;
ASSERT_RTNL();
@@ -639,7 +667,14 @@
mutex_lock(&sdata->local->key_mtx);
- sdata->crypto_tx_tailroom_needed_cnt = 0;
+ WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
+ sdata->crypto_tx_tailroom_pending_dec);
+
+ if (sdata->vif.type == NL80211_IFTYPE_AP) {
+ list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+ WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
+ vlan->crypto_tx_tailroom_pending_dec);
+ }
list_for_each_entry(key, &sdata->key_list, list) {
increment_tailroom_need_count(sdata);
@@ -649,6 +684,22 @@
mutex_unlock(&sdata->local->key_mtx);
}
+void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_sub_if_data *vlan;
+
+ mutex_lock(&sdata->local->key_mtx);
+
+ sdata->crypto_tx_tailroom_needed_cnt = 0;
+
+ if (sdata->vif.type == NL80211_IFTYPE_AP) {
+ list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+ vlan->crypto_tx_tailroom_needed_cnt = 0;
+ }
+
+ mutex_unlock(&sdata->local->key_mtx);
+}
+
void ieee80211_iter_keys(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
void (*iter)(struct ieee80211_hw *hw,
@@ -688,8 +739,8 @@
{
struct ieee80211_key *key, *tmp;
- sdata->crypto_tx_tailroom_needed_cnt -=
- sdata->crypto_tx_tailroom_pending_dec;
+ decrease_tailroom_need_count(sdata,
+ sdata->crypto_tx_tailroom_pending_dec);
sdata->crypto_tx_tailroom_pending_dec = 0;
ieee80211_debugfs_key_remove_mgmt_default(sdata);
@@ -709,6 +760,7 @@
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_sub_if_data *vlan;
+ struct ieee80211_sub_if_data *master;
struct ieee80211_key *key, *tmp;
LIST_HEAD(keys);
@@ -728,8 +780,20 @@
list_for_each_entry_safe(key, tmp, &keys, list)
__ieee80211_key_destroy(key, false);
- WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
- sdata->crypto_tx_tailroom_pending_dec);
+ if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
+ if (sdata->bss) {
+ master = container_of(sdata->bss,
+ struct ieee80211_sub_if_data,
+ u.ap);
+
+ WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
+ master->crypto_tx_tailroom_needed_cnt);
+ }
+ } else {
+ WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
+ sdata->crypto_tx_tailroom_pending_dec);
+ }
+
if (sdata->vif.type == NL80211_IFTYPE_AP) {
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
@@ -793,8 +857,8 @@
*/
mutex_lock(&sdata->local->key_mtx);
- sdata->crypto_tx_tailroom_needed_cnt -=
- sdata->crypto_tx_tailroom_pending_dec;
+ decrease_tailroom_need_count(sdata,
+ sdata->crypto_tx_tailroom_pending_dec);
sdata->crypto_tx_tailroom_pending_dec = 0;
mutex_unlock(&sdata->local->key_mtx);
}
diff --git a/net/mac80211/key.h b/net/mac80211/key.h
index c5a3183..96557dd 100644
--- a/net/mac80211/key.h
+++ b/net/mac80211/key.h
@@ -161,6 +161,7 @@
void ieee80211_free_sta_keys(struct ieee80211_local *local,
struct sta_info *sta);
void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata);
+void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata);
#define key_mtx_dereference(local, ref) \
rcu_dereference_protected(ref, lockdep_is_held(&((local)->key_mtx)))
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 79412f1..b864ebc 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -2023,6 +2023,9 @@
/* add back keys */
list_for_each_entry(sdata, &local->interfaces, list)
+ ieee80211_reset_crypto_tx_tailroom(sdata);
+
+ list_for_each_entry(sdata, &local->interfaces, list)
if (ieee80211_sdata_running(sdata))
ieee80211_enable_keys(sdata);