diff mbox series

[1/2] watchdog: menz069_wdt: fix watchdog initialisation

Message ID 20230418172531.177349-2-jth@kernel.org
State New
Headers
Series watchdog: fixes for menz069_wdt driver |

Commit Message

Johannes Thumshirn April 18, 2023, 5:25 p.m. UTC 
  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@kernel.org>
---
 drivers/watchdog/menz69_wdt.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

Comments

Guenter Roeck April 18, 2023, 6:20 p.m. UTC | #1 
On 4/18/23 10:25, Johannes Thumshirn wrote:
> 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@kernel.org>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   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 8973f98bc6a5..bca0938f3429 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);
diff mbox series

Patch

diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c
index 8973f98bc6a5..bca0938f3429 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);