From 6d10e46be5ac1d0ae787babd3dafd52b30686db5 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 6 Mar 2013 23:09:11 +0100 Subject: [PATCH] mac80211: batch key free synchronize_net() Instead of calling synchronize_net() for every key on an interface or when a station is removed, do it only once for all keys in both of these cases. As a side-effect, removing station keys now always calls synchronize_net() even if there are no keys, which fixes an issue with station removal happening in the driver while the station could still be used for TX. Signed-off-by: Johannes Berg --- net/mac80211/key.c | 81 ++++++++++++++++++++++++++++++++++------- net/mac80211/key.h | 2 + net/mac80211/sta_info.c | 12 ++---- 3 files changed, 73 insertions(+), 22 deletions(-) diff --git a/net/mac80211/key.c b/net/mac80211/key.c index 953887bdc63..67059b88fea 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -406,18 +406,9 @@ static void ieee80211_key_free_common(struct ieee80211_key *key) kfree(key); } -static void ieee80211_key_destroy(struct ieee80211_key *key, - bool delay_tailroom) +static void __ieee80211_key_destroy(struct ieee80211_key *key, + bool delay_tailroom) { - if (!key) - return; - - /* - * Synchronize so the TX path can no longer be using - * this key before we free/remove it. - */ - synchronize_net(); - if (key->local) ieee80211_key_disable_hw_accel(key); @@ -439,6 +430,21 @@ static void ieee80211_key_destroy(struct ieee80211_key *key, ieee80211_key_free_common(key); } +static void ieee80211_key_destroy(struct ieee80211_key *key, + bool delay_tailroom) +{ + if (!key) + return; + + /* + * Synchronize so the TX path can no longer be using + * this key before we free/remove it. + */ + synchronize_net(); + + __ieee80211_key_destroy(key, delay_tailroom); +} + void ieee80211_key_free_unused(struct ieee80211_key *key) { WARN_ON(key->sdata || key->local); @@ -560,6 +566,7 @@ EXPORT_SYMBOL(ieee80211_iter_keys); void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata) { struct ieee80211_key *key, *tmp; + LIST_HEAD(keys); cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk); @@ -571,17 +578,65 @@ void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata) ieee80211_debugfs_key_remove_mgmt_default(sdata); - list_for_each_entry_safe(key, tmp, &sdata->key_list, list) - ieee80211_key_free(key, false); + list_for_each_entry_safe(key, tmp, &sdata->key_list, list) { + ieee80211_key_replace(key->sdata, key->sta, + key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, + key, NULL); + list_add_tail(&key->list, &keys); + } ieee80211_debugfs_key_update_default(sdata); + if (!list_empty(&keys)) { + synchronize_net(); + 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); mutex_unlock(&sdata->local->key_mtx); } +void ieee80211_free_sta_keys(struct ieee80211_local *local, + struct sta_info *sta) +{ + struct ieee80211_key *key, *tmp; + LIST_HEAD(keys); + int i; + + mutex_lock(&local->key_mtx); + for (i = 0; i < NUM_DEFAULT_KEYS; i++) { + key = key_mtx_dereference(local, sta->gtk[i]); + if (!key) + continue; + ieee80211_key_replace(key->sdata, key->sta, + key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, + key, NULL); + list_add(&key->list, &keys); + } + + key = key_mtx_dereference(local, sta->ptk); + if (key) { + ieee80211_key_replace(key->sdata, key->sta, + key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, + key, NULL); + list_add(&key->list, &keys); + } + + /* + * NB: the station code relies on this being + * done even if there aren't any keys + */ + synchronize_net(); + + list_for_each_entry_safe(key, tmp, &keys, list) + __ieee80211_key_destroy(key, true); + + mutex_unlock(&local->key_mtx); +} + void ieee80211_delayed_tailroom_dec(struct work_struct *wk) { struct ieee80211_sub_if_data *sdata; diff --git a/net/mac80211/key.h b/net/mac80211/key.h index a353ddd63b5..e8de3e6d780 100644 --- a/net/mac80211/key.h +++ b/net/mac80211/key.h @@ -141,6 +141,8 @@ void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx, void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx); void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata); +void ieee80211_free_sta_keys(struct ieee80211_local *local, + struct sta_info *sta); void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata); #define key_mtx_dereference(local, ref) \ diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 2961f3d6b20..11216bc13b2 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -783,7 +783,7 @@ int __must_check __sta_info_destroy(struct sta_info *sta) { struct ieee80211_local *local; struct ieee80211_sub_if_data *sdata; - int ret, i; + int ret; might_sleep(); @@ -810,14 +810,8 @@ int __must_check __sta_info_destroy(struct sta_info *sta) list_del_rcu(&sta->list); - mutex_lock(&local->key_mtx); - for (i = 0; i < NUM_DEFAULT_KEYS; i++) - ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i]), - true); - if (sta->ptk) - ieee80211_key_free(key_mtx_dereference(local, sta->ptk), - true); - mutex_unlock(&local->key_mtx); + /* this always calls synchronize_net() */ + ieee80211_free_sta_keys(local, sta); sta->dead = true; -- 2.41.0