mac80211: free all AP/VLAN keys at once

When the AP interface is stopped, free all AP and VLAN keys at
once to only require synchronize_net() once. Since that does
synchronize_net(), also move two such calls into the function
(using the new force_synchronize parameter) to avoid doing it
twice.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 18b56fb..8718401 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1098,10 +1098,7 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
                kfree_rcu(old_probe_resp, rcu_head);
 
        __sta_info_flush(sdata, true);
-       synchronize_net();
-       list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
-               ieee80211_free_keys(vlan);
-       ieee80211_free_keys(sdata);
+       ieee80211_free_keys(sdata, true);
 
        sdata->vif.bss_conf.enable_beacon = false;
        sdata->vif.bss_conf.ssid_len = 0;

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 687d4ea..3d2168c 100644 (file)
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -889,18 +889,15 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
                cancel_work_sync(&sdata->work);
                /*
                 * When we get here, the interface is marked down.
+                * Free the remaining keys, if there are any
+                * (shouldn't be, except maybe in WDS mode?)
                 *
-                * We need synchronize_rcu() to wait for the RX path in
-                * case it is using the interface and enqueuing frames
-                * at this very time on another CPU.
+                * Force the key freeing to always synchronize_net()
+                * to wait for the RX path in case it is using this
+                * interface enqueuing frames * at this very time on
+                * another CPU.
                 */
-               synchronize_rcu();
-
-               /*
-                * Free all remaining keys, there shouldn't be any,
-                * except maybe in WDS mode?
-                */
-               ieee80211_free_keys(sdata);
+               ieee80211_free_keys(sdata, true);
 
                /* fall through */
        case NL80211_IFTYPE_AP:
@@ -1026,7 +1023,7 @@ static void ieee80211_teardown_sdata(struct ieee80211_sub_if_data *sdata)
        int i;
 
        /* free extra data */
-       ieee80211_free_keys(sdata);
+       ieee80211_free_keys(sdata, false);
 
        ieee80211_debugfs_remove_netdev(sdata);
 

diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 12e6154..6ff65a1 100644 (file)
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -589,14 +589,10 @@ void ieee80211_iter_keys(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_iter_keys);
 
-void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata)
+static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
+                                     struct list_head *keys)
 {
        struct ieee80211_key *key, *tmp;
-       LIST_HEAD(keys);
-
-       cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
-
-       mutex_lock(&sdata->local->key_mtx);
 
        sdata->crypto_tx_tailroom_needed_cnt -=
                sdata->crypto_tx_tailroom_pending_dec;
@@ -608,21 +604,45 @@ void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata)
                ieee80211_key_replace(key->sdata, key->sta,
                                key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE,
                                key, NULL);
-               list_add_tail(&key->list, &keys);
+               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);
+void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
+                        bool force_synchronize)
+{
+       struct ieee80211_local *local = sdata->local;
+       struct ieee80211_sub_if_data *vlan;
+       struct ieee80211_key *key, *tmp;
+       LIST_HEAD(keys);
+
+       cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk);
+
+       mutex_lock(&local->key_mtx);
+
+       ieee80211_free_keys_iface(sdata, &keys);
+
+       if (sdata->vif.type == NL80211_IFTYPE_AP) {
+               list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+                       ieee80211_free_keys_iface(vlan, &keys);
        }
 
+       if (!list_empty(&keys) || force_synchronize)
+               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);
+       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);
+       }
 
-       mutex_unlock(&sdata->local->key_mtx);
+       mutex_unlock(&local->key_mtx);
 }
 
 void ieee80211_free_sta_keys(struct ieee80211_local *local,

diff --git a/net/mac80211/key.h b/net/mac80211/key.h
index 0aebb88..19db686 100644 (file)
--- a/net/mac80211/key.h
+++ b/net/mac80211/key.h
@@ -136,7 +136,8 @@ void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
                               bool uni, bool multi);
 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_keys(struct ieee80211_sub_if_data *sdata,
+                        bool force_synchronize);
 void ieee80211_free_sta_keys(struct ieee80211_local *local,
                             struct sta_info *sta);
 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata);