Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 1 Feb 2021 15:24:27 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Kalle Valo <kvalo@codeaurora.org>
Cc:     Carl Huang <cjhuang@codeaurora.org>, ath11k@lists.infradead.org,
        linux-wireless@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [PATCH] ath11k: fix a locking bug in ath11k_mac_op_start()
Message-ID: <YBfy+zc3XkiyIe6t@mwanda>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Precedence: bulk

This error path leads to a Smatch warning:

    drivers/net/wireless/ath/ath11k/mac.c:4269 ath11k_mac_op_start()
    error: double unlocked '&ar->conf_mutex' (orig line 4251)

We're not holding the lock when we do the "goto err;" so it leads to a
double unlock.  We should hold the lock because the error path sets
"ar->state" so the right fix is to take the lock before doing the goto.

Fixes: c83c500b55b6 ("ath11k: enable idle power save mode")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 drivers/net/wireless/ath/ath11k/mac.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index c1608f64ea95..12e981e9e3d7 100644
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -4259,6 +4259,7 @@ static int ath11k_mac_op_start(struct ieee80211_hw *hw)
 						1, pdev->pdev_id);
 		if (ret) {
 			ath11k_err(ab, "failed to enable idle ps: %d\n", ret);
+			mutex_lock(&ar->conf_mutex);
 			goto err;
 		}
 	}
-- 
2.29.2