mac80211: station state transition error handling

In the future, when we start notifying drivers,
state transitions could potentially fail. To make
it easier to distinguish between programming bugs
and driver failures:
 * rename sta_info_move_state() to
   sta_info_pre_move_state() which can only be
   called before the station is inserted (and
   check this with a new station flag).
 * rename sta_info_move_state_checked() to just
   plain sta_info_move_state(), as it will be
   the regular function that can fail for more
   than just one reason (bad transition or an
   error from the driver)

This makes the programming model easier -- one of
the functions can only be called before insertion
and can't fail, the other can fail.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 13 insertions, 4 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index de3268c..acc11b5 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1587,10 +1587,19 @@ static bool ieee80211_assoc_success(struct ieee80211_work *wk,
 		return false;
 	}
 
-	sta_info_move_state(sta, IEEE80211_STA_AUTH);
-	sta_info_move_state(sta, IEEE80211_STA_ASSOC);
-	if (!(ifmgd->flags & IEEE80211_STA_CONTROL_PORT))
-		sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
+	err = sta_info_move_state(sta, IEEE80211_STA_AUTH);
+	if (!err)
+		err = sta_info_move_state(sta, IEEE80211_STA_ASSOC);
+	if (!err && !(ifmgd->flags & IEEE80211_STA_CONTROL_PORT))
+		err = sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
+	if (err) {
+		printk(KERN_DEBUG
+		       "%s: failed to move station %pM to desired state\n",
+		       sdata->name, sta->sta.addr);
+		WARN_ON(__sta_info_destroy(sta));
+		mutex_unlock(&sdata->local->sta_mtx);
+		return false;
+	}
 
 	rates = 0;
 	basic_rates = 0;