mac80211: fix no-op authorized transitions

When userspace attempts to authorize a station
that is already authorized, nothing happens as
you'd expect. Similarly, when it unauthorizes
a station that is associated, nothing happens.

However, when it unauthorizes a station that
isn't even associated yet, we erroneously try
to move the station to associated. This seems
to happen occasionally as a result of a race
when wpa_supplicant attempts to unauthorize
the port in managed mode. Particularly with my
new patches to keep stations, it can then move
a station into ASSOCIATED state before we have
really associated, which is really confusing.

I introduced this bug in
"mac80211: refactor station state transitions"
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/cfg.c

@@ -791,7 +791,7 @@ static int sta_apply_parameters(struct ieee80211_local *local,
 		if (set & BIT(NL80211_STA_FLAG_AUTHORIZED))
 			ret = sta_info_move_state_checked(sta,
 					IEEE80211_STA_AUTHORIZED);
-		else
+		else if (test_sta_flag(sta, WLAN_STA_AUTHORIZED))
 			ret = sta_info_move_state_checked(sta,
 					IEEE80211_STA_ASSOC);
 		if (ret)