From 0afe9d4ab9d40c281bdcdd118661fe8e4bdcef18 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sat, 9 Dec 2017 21:10:10 +0100 Subject: [PATCH] mac80211: fix locking in ieee80211_sta_tear_down_BA_sessions Due to overlap between commit 1281103770e9 ("mac80211: Simplify locking in ieee80211_sta_tear_down_BA_sessions()") and the way that Luca modified commit 72e2c3438ba3 ("mac80211: tear down RX aggregations first") when sending it upstream from Intel's internal tree, we get the following warning: WARNING: CPU: 0 PID: 5472 at net/mac80211/agg-tx.c:315 ___ieee80211_stop_tx_ba_session+0x158/0x1f0 since there's no appropriate locking around the call to ___ieee80211_stop_tx_ba_session; Sara's original just had a call to the locked __ieee80211_stop_tx_ba_session (one less underscore) but it looks like Luca modified both of the calls when fixing it up for upstream, leading to the problem at hand. Move the locking appropriately to fix this problem. Reported-by: Kalle Valo Reported-by: Pavel Machek Tested-by: Pavel Machek Signed-off-by: Johannes Berg --- net/mac80211/ht.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c index 167f83b853e6..1621b6ab17ba 100644 --- a/net/mac80211/ht.c +++ b/net/mac80211/ht.c @@ -291,16 +291,15 @@ void ieee80211_sta_tear_down_BA_sessions(struct sta_info *sta, int i; mutex_lock(&sta->ampdu_mlme.mtx); - for (i = 0; i < IEEE80211_NUM_TIDS; i++) { + for (i = 0; i < IEEE80211_NUM_TIDS; i++) ___ieee80211_stop_rx_ba_session(sta, i, WLAN_BACK_RECIPIENT, WLAN_REASON_QSTA_LEAVE_QBSS, reason != AGG_STOP_DESTROY_STA && reason != AGG_STOP_PEER_REQUEST); - } - mutex_unlock(&sta->ampdu_mlme.mtx); for (i = 0; i < IEEE80211_NUM_TIDS; i++) ___ieee80211_stop_tx_ba_session(sta, i, reason); + mutex_unlock(&sta->ampdu_mlme.mtx); /* stopping might queue the work again - so cancel only afterwards */ cancel_work_sync(&sta->ampdu_mlme.work);