mac80211: call skb_dequeue/ieee80211_free_txskb instead of __skb_queue_purge

Fixes more wifi status skb leaks, leading to hostapd/wpa_supplicant hangs.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

4 files changed, 20 insertions, 6 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 8c804550465b..156e5835e37f 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1314,6 +1314,8 @@ netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
                                          struct net_device *dev);
 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
                                        struct net_device *dev);
+void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
+                              struct sk_buff_head *skbs);
 
 /* HT */
 void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 89ccd3ec7eb8..3b5911ed4312 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -117,8 +117,8 @@ static void free_sta_work(struct work_struct *wk)
 
         for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
                 local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
-                __skb_queue_purge(&sta->ps_tx_buf[ac]);
-                __skb_queue_purge(&sta->tx_filtered[ac]);
+                ieee80211_purge_tx_queue(&local->hw, &sta->ps_tx_buf[ac]);
+                ieee80211_purge_tx_queue(&local->hw, &sta->tx_filtered[ac]);
         }
 
 #ifdef CONFIG_MAC80211_MESH
@@ -141,7 +141,7 @@ static void free_sta_work(struct work_struct *wk)
                 tid_tx = rcu_dereference_raw(sta->ampdu_mlme.tid_tx[i]);
                 if (!tid_tx)
                         continue;
-                __skb_queue_purge(&tid_tx->pending);
+                ieee80211_purge_tx_queue(&local->hw, &tid_tx->pending);
                 kfree(tid_tx);
         }
 
diff --git a/net/mac80211/status.c b/net/mac80211/status.c
index 3af0cc4130f1..101eb88a2b78 100644
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -668,3 +668,12 @@ void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
         dev_kfree_skb_any(skb);
 }
 EXPORT_SYMBOL(ieee80211_free_txskb);
+
+void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
+                              struct sk_buff_head *skbs)
+{
+        struct sk_buff *skb;
+
+        while ((skb = __skb_dequeue(skbs)))
+                ieee80211_free_txskb(hw, skb);
+}
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index c9bf83f36657..b858ebe41fda 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1358,7 +1358,7 @@ static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
                 if (tx->skb)
                         ieee80211_free_txskb(&tx->local->hw, tx->skb);
                 else
-                        __skb_queue_purge(&tx->skbs);
+                        ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
                 return -1;
         } else if (unlikely(res == TX_QUEUED)) {
                 I802_DEBUG_INC(tx->local->tx_handlers_queued);
@@ -2120,10 +2120,13 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
  */
 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
 {
+        struct sk_buff *skb;
         int i;
 
-        for (i = 0; i < local->hw.queues; i++)
-                skb_queue_purge(&local->pending[i]);
+        for (i = 0; i < local->hw.queues; i++) {
+                while ((skb = skb_dequeue(&local->pending[i])) != NULL)
+                        ieee80211_free_txskb(&local->hw, skb);
+        }
 }
 
 /*