This is a note to let you know that I've just added the patch titled watchdog: menz069_wdt: fix watchdog initialisation to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: watchdog-menz069_wdt-fix-watchdog-initialisation.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3fb4ea6c321847acdad9075f7043862eb62cce2b Author: Johannes Thumshirn <jth@xxxxxxxxxx> Date: Tue Apr 18 19:25:30 2023 +0200 watchdog: menz069_wdt: fix watchdog initialisation [ 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> diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c index ed18238c54074..96a25d18ab643 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);