mac80211: don't stop a single aggregation session twice
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.
Cc: stable@vger.kernel.org
Reported-by: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 2ac0339..674b345 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -160,6 +160,12 @@
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);
@@ -168,6 +174,8 @@
return 0;
}
+ set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
+
spin_unlock_bh(&sta->lock);
#ifdef CONFIG_MAC80211_HT_DEBUG
@@ -175,8 +183,6 @@
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);
/*