Commit 1a28c78b authored Mar 10, 2009 by Herton Ronaldo Krzesinski Committed by John W. Linville Mar 16, 2009

mac80211: deauth before flushing STA information



Even after commit "mac80211: deauth when interface is marked down"
(e327b847 on Linus tree), userspace still isn't notified when interface
goes down. There isn't a problem with this commit, but because of other
code changes it doesn't work on kernels >= 2.6.28 (works if same/similar
change applied on 2.6.27 for example).

The issue is as follows: after commit "mac80211: restructure disassoc/deauth
flows" in 2.6.28, the call to ieee80211_sta_deauthenticate added by
commit e327b847 will not work: because we do sta_info_flush(local, sdata)
inside ieee80211_stop (iface.c), all stations in interface are cleared, so
when calling ieee80211_sta_deauthenticate->ieee80211_set_disassoc (mlme.c),
inside ieee80211_set_disassoc we have this in the beginning:

         sta = sta_info_get(local, ifsta->bssid);
         if (!sta) {

The !sta check triggers, thus the function returns early and
ieee80211_sta_send_apinfo(sdata, ifsta) later isn't called, so
wpa_supplicant/userspace isn't notified with SIOCGIWAP.

This commit moves deauthentication to before flushing STA info
(sta_info_flush), thus the above can't happen and userspace is really
notified when interface goes down.

Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent af88b907

net/mac80211/iface.c

+12 −4

Original line number	Diff line number	Diff line
		@@ -369,6 +369,18 @@ static int ieee80211_stop(struct net_device *dev)

		rcu_read_unlock();

		/*
		* Announce that we are leaving the network, in case we are a
		* station interface type. This must be done before removing
		* all stations associated with sta_info_flush, otherwise STA
		* information will be gone and no announce being done.
		*/
		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
		if (sdata->u.mgd.state != IEEE80211_STA_MLME_DISABLED)
		ieee80211_sta_deauthenticate(sdata,
		WLAN_REASON_DEAUTH_LEAVING);
		}

		/*
		* Remove all stations associated with this interface.
		*
		@@ -454,10 +466,6 @@ static int ieee80211_stop(struct net_device *dev)
		netif_addr_unlock_bh(local->mdev);
		break;
		case NL80211_IFTYPE_STATION:
		/* Announce that we are leaving the network. */
		if (sdata->u.mgd.state != IEEE80211_STA_MLME_DISABLED)
		ieee80211_sta_deauthenticate(sdata,
		WLAN_REASON_DEAUTH_LEAVING);
		memset(sdata->u.mgd.bssid, 0, ETH_ALEN);
		del_timer_sync(&sdata->u.mgd.chswitch_timer);
		del_timer_sync(&sdata->u.mgd.timer);

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