diff mbox

mac80211: fix IBSS teardown race

Message ID 1307532343.3961.9.camel@jlt3.sipsolutions.net (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Johannes Berg June 8, 2011, 11:25 a.m. UTC 
From: Johannes Berg <johannes.berg@intel.com>

Ignacy reports that sometimes after leaving an IBSS
joining a new one didn't work because there still
were stations on the list. He fixed it by flushing
stations when attempting to join a new IBSS, but
this shouldn't be happening in the first case. When
I looked into it I saw a race condition in teardown
that could cause stations to be added after flush,
and thus cause this situation. Ignacy confirms that
after applying my patch he hasn't seen this happen
again.

Reported-by: Ignacy Gawedzki <i@lri.fr>
Debugged-by: Ignacy Gawedzki <i@lri.fr>
Tested-by: Ignacy Gawedzki <i@lri.fr>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/ibss.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)



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diff mbox

Patch

--- a/net/mac80211/ibss.c	2011-06-08 07:55:21.000000000 +0200
+++ b/net/mac80211/ibss.c	2011-06-08 13:16:20.000000000 +0200
@@ -965,6 +965,10 @@  int ieee80211_ibss_leave(struct ieee8021
 
 	mutex_lock(&sdata->u.ibss.mtx);
 
+	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
+	memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
+	sdata->u.ibss.ssid_len = 0;
+
 	active_ibss = ieee80211_sta_active_ibss(sdata);
 
 	if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
@@ -999,8 +1003,6 @@  int ieee80211_ibss_leave(struct ieee8021
 	kfree_skb(skb);
 
 	skb_queue_purge(&sdata->skb_queue);
-	memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
-	sdata->u.ibss.ssid_len = 0;
 
 	del_timer_sync(&sdata->u.ibss.timer);