From 64a1b241dd84ed6b12b62bbb67b380609bdd50b2 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 24 Nov 2011 20:06:14 +0100 Subject: mac80211: don't stop a single aggregation session twice 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 Signed-off-by: Johannes Berg Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- net/mac80211/agg-tx.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c index c8be8eff70da..23418753a4d5 100644 --- a/net/mac80211/agg-tx.c +++ b/net/mac80211/agg-tx.c @@ -162,6 +162,12 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, 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(struct sta_info *sta, u16 tid, 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(struct sta_info *sta, u16 tid, 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); /* -- cgit v1.2.3