wifi: cfg80211: hold wiphy lock in auto-disconnect

[ Upstream commit e9da6df ]

Most code paths in cfg80211 already hold the wiphy lock,
mostly by virtue of being called from nl80211, so make
the auto-disconnect worker also hold it, aligning the
locking promises between different parts of cfg80211.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Stable-dep-of: 37c20b2 ("wifi: cfg80211: fix cqm_config access race")
Signed-off-by: Sasha Levin <sashal@kernel.org>

net/wireless/core.c

@@ -1162,10 +1162,6 @@ static void _cfg80211_unregister_wdev(struct wireless_dev *wdev,
 	kfree_sensitive(wdev->wext.keys);
 	wdev->wext.keys = NULL;
 #endif
-	/* only initialized if we have a netdev */
-	if (wdev->netdev)
-		flush_work(&wdev->disconnect_wk);
-
 	cfg80211_cqm_config_free(wdev);
 
 	/*
@@ -1439,6 +1435,8 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
 		cfg80211_leave(rdev, wdev);
 		cfg80211_remove_links(wdev);
 		wiphy_unlock(&rdev->wiphy);
+		/* since we just did cfg80211_leave() nothing to do there */
+		cancel_work_sync(&wdev->disconnect_wk);
 		break;
 	case NETDEV_DOWN:
 		wiphy_lock(&rdev->wiphy);

net/wireless/sme.c

@@ -5,7 +5,7 @@
  * (for nl80211's connect() and wext)
  *
  * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
- * Copyright (C) 2009, 2020, 2022 Intel Corporation. All rights reserved.
+ * Copyright (C) 2009, 2020, 2022-2023 Intel Corporation. All rights reserved.
  * Copyright 2017	Intel Deutschland GmbH
  */
 
@@ -1555,6 +1555,7 @@ void cfg80211_autodisconnect_wk(struct work_struct *work)
 		container_of(work, struct wireless_dev, disconnect_wk);
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 
+	wiphy_lock(wdev->wiphy);
 	wdev_lock(wdev);
 
 	if (wdev->conn_owner_nlportid) {
@@ -1593,4 +1594,5 @@ void cfg80211_autodisconnect_wk(struct work_struct *work)
 	}
 
 	wdev_unlock(wdev);
+	wiphy_unlock(wdev->wiphy);
 }