From d01b6332079910051ae08b763c84018e37a2f425 Mon Sep 17 00:00:00 2001 From: Madhuparna Bhowmik Date: Fri, 7 Aug 2020 16:59:02 +0530 Subject: [PATCH] drivers: watchdog: rdc321x_wdt: Fix race condition bugs [ 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 Reviewed-by: Guenter Roeck Reviewed-by: Florian Fainelli Link: https://lore.kernel.org/r/20200807112902.28764-1-madhuparnabhowmik10@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin --- 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 2e608ae6cbc7..e0efbc583198 100644 --- a/drivers/watchdog/rdc321x_wdt.c +++ b/drivers/watchdog/rdc321x_wdt.c @@ -230,6 +230,8 @@ 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) { @@ -244,14 +246,11 @@ 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); timer_setup(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0); - rdc321x_wdt_device.default_ticks = ticks; - dev_info(&pdev->dev, "watchdog init success\n"); return 0;