Re: [PATCH 3/5] input: twl6040-vibra: fix NULL pointer dereference by removing workqueue

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Mon, Apr 18, 2016 at 09:55:39PM +0200, H. Nikolaus Schaller wrote:
> commit 21fb9f0d5e91 ("Input: twl6040-vibra - use system workqueue")
> 
> says that it switches to use the system workqueue but it did neither
> 
> - remove the workqueue struct variable
> - replace code to really use the system workqueue
> 
> Instead it calls queue_work() on uninitialized info->workqueue.
> 
> The result is a NULL pointer dereference in vibra_play().
> 
> Solution: use schedule_work
> 
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>

Applied, thank you.

> ---
>  drivers/input/misc/twl6040-vibra.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/input/misc/twl6040-vibra.c b/drivers/input/misc/twl6040-vibra.c
> index 1e9902d..3805129 100644
> --- a/drivers/input/misc/twl6040-vibra.c
> +++ b/drivers/input/misc/twl6040-vibra.c
> @@ -45,7 +45,6 @@
>  struct vibra_info {
>  	struct device *dev;
>  	struct input_dev *input_dev;
> -	struct workqueue_struct *workqueue;
>  	struct work_struct play_work;
>  	struct mutex mutex;
>  	int irq;
> @@ -213,7 +212,7 @@ static int vibra_play(struct input_dev *input, void *data,
>  	info->strong_speed = effect->u.rumble.strong_magnitude;
>  	info->direction = effect->direction < EFFECT_DIR_180_DEG ? 1 : -1;
>  
> -	ret = queue_work(info->workqueue, &info->play_work);
> +	ret = schedule_work(&info->play_work);
>  	if (!ret) {
>  		dev_info(&input->dev, "work is already on queue\n");
>  		return ret;
> -- 
> 2.7.3
> 

-- 
Dmitry