linux-kernel - [PATCH AUTOSEL 5.1 004/219] ath9k: Don't trust TX status TID number when reporting airtime

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: <20190715140341.6443-4-sashal@kernel.org>
Date:   Mon, 15 Jul 2019 10:00:05 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Toke Høiland-Jørgensen <toke@...hat.com>,
        Miguel Catalan Cid <miguel.catalan@...at.net>,
        Kalle Valo <kvalo@...eaurora.org>,
        Sasha Levin <sashal@...nel.org>,
        linux-wireless@...r.kernel.org, netdev@...r.kernel.org
Subject: [PATCH AUTOSEL 5.1 004/219] ath9k: Don't trust TX status TID number when reporting airtime

From: Toke Høiland-Jørgensen <toke@...hat.com>

[ Upstream commit 389b72e58259336c2d56d58b660b79cf4b9e0dcb ]

As already noted a comment in ath_tx_complete_aggr(), the hardware will
occasionally send a TX status with the wrong tid number. If we trust the
value, airtime usage will be reported to the wrong AC, which can cause the
deficit on that AC to become very low, blocking subsequent attempts to
transmit.

To fix this, account airtime usage to the TID number from the original skb,
instead of the one in the hardware TX status report.

Reported-by: Miguel Catalan Cid <miguel.catalan@...at.net>
Signed-off-by: Toke Høiland-Jørgensen <toke@...hat.com>
Signed-off-by: Kalle Valo <kvalo@...eaurora.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/net/wireless/ath/ath9k/xmit.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index b17e1ca40995..3be0aeedb9b5 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -668,7 +668,8 @@ static bool bf_is_ampdu_not_probing(struct ath_buf *bf)
 static void ath_tx_count_airtime(struct ath_softc *sc,
 				 struct ieee80211_sta *sta,
 				 struct ath_buf *bf,
-				 struct ath_tx_status *ts)
+				 struct ath_tx_status *ts,
+				 u8 tid)
 {
 	u32 airtime = 0;
 	int i;
@@ -679,7 +680,7 @@ static void ath_tx_count_airtime(struct ath_softc *sc,
 		airtime += rate_dur * bf->rates[i].count;
 	}
 
-	ieee80211_sta_register_airtime(sta, ts->tid, airtime, 0);
+	ieee80211_sta_register_airtime(sta, tid, airtime, 0);
 }
 
 static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
@@ -709,7 +710,7 @@ static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
 	if (sta) {
 		struct ath_node *an = (struct ath_node *)sta->drv_priv;
 		tid = ath_get_skb_tid(sc, an, bf->bf_mpdu);
-		ath_tx_count_airtime(sc, sta, bf, ts);
+		ath_tx_count_airtime(sc, sta, bf, ts, tid->tidno);
 		if (ts->ts_status & (ATH9K_TXERR_FILT | ATH9K_TXERR_XRETRY))
 			tid->clear_ps_filter = true;
 	}
-- 
2.20.1