netdev - [PATCH] net: wireless: ath: ath9k: Fix a possible data race in ath_chanctx_set

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-next>] [day] [month] [year] [list]

Date:   Tue,  8 May 2018 16:06:36 +0800
From:   Jia-Ju Bai <baijiaju1990@...il.com>
To:     ath9k-devel@....qualcomm.com, kvalo@...eaurora.org
Cc:     linux-wireless@...r.kernel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org, Jia-Ju Bai <baijiaju1990@...il.com>
Subject: [PATCH] net: wireless: ath: ath9k: Fix a possible data race in ath_chanctx_set_next

The write operation to "sc->next_chan" is protected by
the lock on line 1287, but the read operation to
this data on line 1262 is not protected by the lock.
Thus, there may exist a data race for "sc->next_chan".

To fix this data race, the read operation to "sc->next_chan" 
should be also protected by the lock.

Signed-off-by: Jia-Ju Bai <baijiaju1990@...il.com>
---
 drivers/net/wireless/ath/ath9k/channel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/channel.c b/drivers/net/wireless/ath/ath9k/channel.c
index 1b05b5d7a038..ed3cd5523481 100644
--- a/drivers/net/wireless/ath/ath9k/channel.c
+++ b/drivers/net/wireless/ath/ath9k/channel.c
@@ -1257,12 +1257,12 @@ void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 			"Stopping current chanctx: %d\n",
 			sc->cur_chan->chandef.center_freq1);
 		sc->cur_chan->stopped = true;
-		spin_unlock_bh(&sc->chan_lock);
 
 		if (sc->next_chan == &sc->offchannel.chan) {
 			getrawmonotonic(&ts);
 			measure_time = true;
 		}
+		spin_unlock_bh(&sc->chan_lock);
 
 		ath9k_chanctx_stop_queues(sc, sc->cur_chan);
 		queues_stopped = true;
-- 
2.17.0