Re: [PATCH] watchdog: Fix memleak in watchdog_cdev_register

[Guenter Roeck]

On Mon, Aug 24, 2020 at 10:40:01AM +0800, Dinghao Liu wrote:
> When watchdog_kworker is NULL, we should free wd_data
> before the function returns to prevent memleak.
> 
> Fixes: 664a39236e718 ("watchdog: Introduce hardware maximum heartbeat in watchdog core")
> Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
>  drivers/watchdog/watchdog_dev.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
> index 6798addabd5a..785270ee337c 100644
> --- a/drivers/watchdog/watchdog_dev.c
> +++ b/drivers/watchdog/watchdog_dev.c
> @@ -994,8 +994,10 @@ static int watchdog_cdev_register(struct watchdog_device *wdd)
>  	wd_data->wdd = wdd;
>  	wdd->wd_data = wd_data;
>  
> -	if (IS_ERR_OR_NULL(watchdog_kworker))
> +	if (IS_ERR_OR_NULL(watchdog_kworker)) {
> +		kfree(wd_data);
>  		return -ENODEV;
> +	}
>  
>  	device_initialize(&wd_data->dev);
>  	wd_data->dev.devt = MKDEV(MAJOR(watchdog_devt), wdd->id);
> -- 
> 2.17.1
>