mac80211: mark station unauthorized before key removal

If a station is still marked as authorized, mark it as no longer
so before removing its keys. This allows frames transmitted to it
to be rejected, providing additional protection against leaking
plain text data during the disconnection flow.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200326155133.ccb4fb0bb356.If48f0f0504efdcf16b8921f48c6d3bb2cb763c99@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/sta_info.c

@@ -4,7 +4,7 @@
  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
  * Copyright (C) 2015 - 2017 Intel Deutschland GmbH
- * Copyright (C) 2018-2019 Intel Corporation
+ * Copyright (C) 2018-2020 Intel Corporation
  */
 
 #include <linux/module.h>
@@ -1049,6 +1049,11 @@ static void __sta_info_destroy_part2(struct sta_info *sta)
 	might_sleep();
 	lockdep_assert_held(&local->sta_mtx);
 
+	while (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
+		ret = sta_info_move_state(sta, IEEE80211_STA_ASSOC);
+		WARN_ON_ONCE(ret);
+	}
+
 	/* now keys can no longer be reached */
 	ieee80211_free_sta_keys(local, sta);