3 files changed, 23 insertions, 9 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index fb306814576a..a6893602f87a 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2582,7 +2582,7 @@ static int ieee80211_cancel_roc(struct ieee80211_local *local,
 			list_del(&dep->list);
 			mutex_unlock(&local->mtx);
 
-			ieee80211_roc_notify_destroy(dep);
+			ieee80211_roc_notify_destroy(dep, true);
 			return 0;
 		}
 
@@ -2622,7 +2622,7 @@ static int ieee80211_cancel_roc(struct ieee80211_local *local,
 			ieee80211_start_next_roc(local);
 		mutex_unlock(&local->mtx);
 
-		ieee80211_roc_notify_destroy(found);
+		ieee80211_roc_notify_destroy(found, true);
 	} else {
 		/* work may be pending so use it all the time */
 		found->abort = true;
@@ -2632,6 +2632,8 @@ static int ieee80211_cancel_roc(struct ieee80211_local *local,
 
 		/* work will clean up etc */
 		flush_delayed_work(&found->work);
+		WARN_ON(!found->to_be_freed);
+		kfree(found);
 	}
 
 	return 0;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 388580a1bada..7bdefd901f9d 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -309,6 +309,7 @@ struct ieee80211_roc_work {
 	struct ieee80211_channel *chan;
 
 	bool started, abort, hw_begun, notified;
+	bool to_be_freed;
 
 	unsigned long hw_start_time;
 
@@ -1347,7 +1348,7 @@ void ieee80211_offchannel_return(struct ieee80211_local *local);
 void ieee80211_roc_setup(struct ieee80211_local *local);
 void ieee80211_start_next_roc(struct ieee80211_local *local);
 void ieee80211_roc_purge(struct ieee80211_sub_if_data *sdata);
-void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc);
+void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc, bool free);
 void ieee80211_sw_roc_work(struct work_struct *work);
 void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc);
 
diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index cc79b4a2e821..430bd254e496 100644
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -297,10 +297,13 @@ void ieee80211_start_next_roc(struct ieee80211_local *local)
 	}
 }
 
-void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc)
+void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc, bool free)
 {
 	struct ieee80211_roc_work *dep, *tmp;
 
+	if (WARN_ON(roc->to_be_freed))
+		return;
+
 	/* was never transmitted */
 	if (roc->frame) {
 		cfg80211_mgmt_tx_status(&roc->sdata->wdev,
@@ -316,9 +319,12 @@ void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc)
 						   GFP_KERNEL);
 
 	list_for_each_entry_safe(dep, tmp, &roc->dependents, list)
-		ieee80211_roc_notify_destroy(dep);
+		ieee80211_roc_notify_destroy(dep, true);
 
-	kfree(roc);
+	if (free)
+		kfree(roc);
+	else
+		roc->to_be_freed = true;
 }
 
 void ieee80211_sw_roc_work(struct work_struct *work)
@@ -331,6 +337,9 @@ void ieee80211_sw_roc_work(struct work_struct *work)
 
 	mutex_lock(&local->mtx);
 
+	if (roc->to_be_freed)
+		goto out_unlock;
+
 	if (roc->abort)
 		goto finish;
 
@@ -370,7 +379,7 @@ void ieee80211_sw_roc_work(struct work_struct *work)
  finish:
 		list_del(&roc->list);
 		started = roc->started;
-		ieee80211_roc_notify_destroy(roc);
+		ieee80211_roc_notify_destroy(roc, !roc->abort);
 
 		if (started) {
 			drv_flush(local, false);
@@ -410,7 +419,7 @@ static void ieee80211_hw_roc_done(struct work_struct *work)
 
 	list_del(&roc->list);
 
-	ieee80211_roc_notify_destroy(roc);
+	ieee80211_roc_notify_destroy(roc, true);
 
 	/* if there's another roc, start it now */
 	ieee80211_start_next_roc(local);
@@ -460,12 +469,14 @@ void ieee80211_roc_purge(struct ieee80211_sub_if_data *sdata)
 	list_for_each_entry_safe(roc, tmp, &tmp_list, list) {
 		if (local->ops->remain_on_channel) {
 			list_del(&roc->list);
-			ieee80211_roc_notify_destroy(roc);
+			ieee80211_roc_notify_destroy(roc, true);
 		} else {
 			ieee80211_queue_delayed_work(&local->hw, &roc->work, 0);
 
 			/* work will clean up etc */
 			flush_delayed_work(&roc->work);
+			WARN_ON(!roc->to_be_freed);
+			kfree(roc);
 		}
 	}