Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:46662 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751049AbZGYJ6h (ORCPT ); Sat, 25 Jul 2009 05:58:37 -0400 Subject: [PATCH] mac80211: fix receiving deauth From: Johannes Berg To: John Linville Cc: Marcel Holtmann , linux-wireless Content-Type: text/plain Date: Sat, 25 Jul 2009 11:58:36 +0200 Message-Id: <1248515916.19945.1.camel@johannes.local> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: Marcel reported a warning, which quite obviously comes from an oversight in the code handling deauth frames, and which resulted in multiple follow-up warnings due to this missing handling. This patch adds the missing deauth handling (telling cfg80211 about it) and also removes the follow-up warnings since they could happen due to races even if nothing is wrong. I've explained the races in the comments. Signed-off-by: Johannes Berg Reported-by: Marcel Holtmann --- net/mac80211/mlme.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) --- wireless-testing.orig/net/mac80211/mlme.c 2009-07-25 11:03:12.000000000 +0200 +++ wireless-testing/net/mac80211/mlme.c 2009-07-25 11:55:35.000000000 +0200 @@ -2003,6 +2003,9 @@ static void ieee80211_sta_rx_queued_mgmt case RX_MGMT_CFG80211_ASSOC: cfg80211_send_rx_assoc(sdata->dev, (u8 *) mgmt, skb->len); break; + case RX_MGMT_CFG80211_DEAUTH: + cfg80211_send_deauth(sdata->dev, (u8 *)mgmt, skb->len, NULL); + break; default: WARN(1, "unexpected: %d", rma); } @@ -2498,8 +2501,13 @@ int ieee80211_mgd_deauth(struct ieee8021 } } - /* cfg80211 should catch this... */ - if (WARN_ON(!bssid)) { + /* + * cfg80211 should catch this ... but it's racy since + * we can receive a deauth frame, process it, hand it + * to cfg80211 while that's in a locked section already + * trying to tell us that the user wants to disconnect. + */ + if (!bssid) { mutex_unlock(&ifmgd->mtx); return -ENOLINK; } @@ -2524,8 +2532,13 @@ int ieee80211_mgd_disassoc(struct ieee80 mutex_lock(&ifmgd->mtx); - /* cfg80211 should catch that */ - if (WARN_ON(&ifmgd->associated->cbss != req->bss)) { + /* + * cfg80211 should catch this ... but it's racy since + * we can receive a disassoc frame, process it, hand it + * to cfg80211 while that's in a locked section already + * trying to tell us that the user wants to disconnect. + */ + if (&ifmgd->associated->cbss != req->bss) { mutex_unlock(&ifmgd->mtx); return -ENOLINK; }