linux-kernel - [044/104] mac80211: dont stop a single aggregation session twice

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20111207161218.387461686@clark.kroah.org>
Date:	Wed, 07 Dec 2011 08:11:46 -0800
From:	Greg KH <gregkh@...e.de>
To:	<linux-kernel@...r.kernel.org>, <stable@...r.kernel.org>
Cc:	<torvalds@...ux-foundation.org>, <akpm@...ux-foundation.org>,
	<alan@...rguk.ukuu.org.uk>,
	Johannes Berg <johannes.berg@...el.com>,
	"John W. Linville" <linville@...driver.com>
Subject: [044/104] mac80211: dont stop a single aggregation session twice

3.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johannes Berg <johannes.berg@...el.com>

commit 24f50a9d165745fd0701c6e089d35f58a229ea69 upstream.

Nikolay noticed (by code review) that mac80211 can
attempt to stop an aggregation session while it is
already being stopped. So to fix it, check whether
stop is already being done and bail out if so.

Also move setting the STOPPING state into the lock
so things are properly atomic.

Reported-by: Nikolay Martynov <mar.kolya@...il.com>
Signed-off-by: Johannes Berg <johannes.berg@...el.com>
Signed-off-by: John W. Linville <linville@...driver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>

---
 net/mac80211/agg-tx.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -162,6 +162,12 @@ int ___ieee80211_stop_tx_ba_session(stru
 		return -ENOENT;
 	}
 
+	/* if we're already stopping ignore any new requests to stop */
+	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
+		spin_unlock_bh(&sta->lock);
+		return -EALREADY;
+	}
+
 	if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
 		/* not even started yet! */
 		ieee80211_assign_tid_tx(sta, tid, NULL);
@@ -170,6 +176,8 @@ int ___ieee80211_stop_tx_ba_session(stru
 		return 0;
 	}
 
+	set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
+
 	spin_unlock_bh(&sta->lock);
 
 #ifdef CONFIG_MAC80211_HT_DEBUG
@@ -177,8 +185,6 @@ int ___ieee80211_stop_tx_ba_session(stru
 	       sta->sta.addr, tid);
 #endif /* CONFIG_MAC80211_HT_DEBUG */
 
-	set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
-
 	del_timer_sync(&tid_tx->addba_resp_timer);
 
 	/*


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/