From: Johannes Thumshirn <jth@xxxxxxxxxx> [ Upstream commit 87b22656ca6a896d0378e9e60ffccb0c82f48b08 ] Doing a 'cat /dev/watchdog0' with menz069_wdt as watchdog0 will result in a NULL pointer dereference. This happens because we're passing the wrong pointer to watchdog_register_device(). Fix this by getting rid of the static watchdog_device structure and use the one embedded into the driver's per-instance private data. Signed-off-by: Johannes Thumshirn <jth@xxxxxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230418172531.177349-2-jth@xxxxxxxxxx Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/watchdog/menz69_wdt.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c index 8973f98bc6a56..bca0938f3429f 100644 --- a/drivers/watchdog/menz69_wdt.c +++ b/drivers/watchdog/menz69_wdt.c @@ -98,14 +98,6 @@ static const struct watchdog_ops men_z069_ops = { .set_timeout = men_z069_wdt_set_timeout, }; -static struct watchdog_device men_z069_wdt = { - .info = &men_z069_info, - .ops = &men_z069_ops, - .timeout = MEN_Z069_DEFAULT_TIMEOUT, - .min_timeout = 1, - .max_timeout = MEN_Z069_WDT_COUNTER_MAX / MEN_Z069_TIMER_FREQ, -}; - static int men_z069_probe(struct mcb_device *dev, const struct mcb_device_id *id) { @@ -125,15 +117,19 @@ static int men_z069_probe(struct mcb_device *dev, goto release_mem; drv->mem = mem; + drv->wdt.info = &men_z069_info; + drv->wdt.ops = &men_z069_ops; + drv->wdt.timeout = MEN_Z069_DEFAULT_TIMEOUT; + drv->wdt.min_timeout = 1; + drv->wdt.max_timeout = MEN_Z069_WDT_COUNTER_MAX / MEN_Z069_TIMER_FREQ; - drv->wdt = men_z069_wdt; watchdog_init_timeout(&drv->wdt, 0, &dev->dev); watchdog_set_nowayout(&drv->wdt, nowayout); watchdog_set_drvdata(&drv->wdt, drv); drv->wdt.parent = &dev->dev; mcb_set_drvdata(dev, drv); - return watchdog_register_device(&men_z069_wdt); + return watchdog_register_device(&drv->wdt); release_mem: mcb_release_mem(mem); -- 2.39.2
