[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20201109125027.460261273@linuxfoundation.org>
Date: Mon, 9 Nov 2020 13:54:24 +0100
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org,
Madhuparna Bhowmik <madhuparnabhowmik10@...il.com>,
Guenter Roeck <linux@...ck-us.net>,
Florian Fainelli <f.fainelli@...il.com>,
Wim Van Sebroeck <wim@...ux-watchdog.org>,
Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.9 038/117] drivers: watchdog: rdc321x_wdt: Fix race condition bugs
From: Madhuparna Bhowmik <madhuparnabhowmik10@...il.com>
[ Upstream commit 4b2e7f99cdd314263c9d172bc17193b8b6bba463 ]
In rdc321x_wdt_probe(), rdc321x_wdt_device.queue is initialized
after misc_register(), hence if ioctl is called before its
initialization which can call rdc321x_wdt_start() function,
it will see an uninitialized value of rdc321x_wdt_device.queue,
hence initialize it before misc_register().
Also, rdc321x_wdt_device.default_ticks is accessed in reset()
function called from write callback, thus initialize it before
misc_register().
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@...il.com>
Reviewed-by: Guenter Roeck <linux@...ck-us.net>
Reviewed-by: Florian Fainelli <f.fainelli@...il.com>
Link: https://lore.kernel.org/r/20200807112902.28764-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Guenter Roeck <linux@...ck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@...ux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
drivers/watchdog/rdc321x_wdt.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/watchdog/rdc321x_wdt.c b/drivers/watchdog/rdc321x_wdt.c
index 47a8f1b1087d4..4568af9a165be 100644
--- a/drivers/watchdog/rdc321x_wdt.c
+++ b/drivers/watchdog/rdc321x_wdt.c
@@ -244,6 +244,8 @@ static int rdc321x_wdt_probe(struct platform_device *pdev)
rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
rdc321x_wdt_device.base_reg = r->start;
+ rdc321x_wdt_device.queue = 0;
+ rdc321x_wdt_device.default_ticks = ticks;
err = misc_register(&rdc321x_wdt_misc);
if (err < 0) {
@@ -258,14 +260,11 @@ static int rdc321x_wdt_probe(struct platform_device *pdev)
rdc321x_wdt_device.base_reg, RDC_WDT_RST);
init_completion(&rdc321x_wdt_device.stop);
- rdc321x_wdt_device.queue = 0;
clear_bit(0, &rdc321x_wdt_device.inuse);
setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
- rdc321x_wdt_device.default_ticks = ticks;
-
dev_info(&pdev->dev, "watchdog init success\n");
return 0;
--
2.27.0
Powered by blists - more mailing lists