Re: [PATCH 3/3] Input: 88pm860x-ts: fix child-node lookup

[Dmitry Torokhov]

On Sat, Nov 11, 2017 at 04:43:39PM +0100, Johan Hovold wrote:
> Fix child node-lookup during probe, which ended up searching the whole
> device tree depth-first starting at parent rather than just matching on
> its children.
> 
> To make things worse, the parent node was prematurely freed, while the
> child node was leaked.
> 
> Fixes: 2e57d56747e6 ("mfd: 88pm860x: Device tree support")
> Cc: stable <stable@xxxxxxxxxxxxxxx>     # 3.7
> Cc: Haojian Zhuang <haojian.zhuang@xxxxxxxxx>
> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>

Applied, thank you.

> ---
>  drivers/input/touchscreen/88pm860x-ts.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/input/touchscreen/88pm860x-ts.c b/drivers/input/touchscreen/88pm860x-ts.c
> index 7ed828a51f4c..3486d9403805 100644
> --- a/drivers/input/touchscreen/88pm860x-ts.c
> +++ b/drivers/input/touchscreen/88pm860x-ts.c
> @@ -126,7 +126,7 @@ static int pm860x_touch_dt_init(struct platform_device *pdev,
>  	int data, n, ret;
>  	if (!np)
>  		return -ENODEV;
> -	np = of_find_node_by_name(np, "touch");
> +	np = of_get_child_by_name(np, "touch");
>  	if (!np) {
>  		dev_err(&pdev->dev, "Can't find touch node\n");
>  		return -EINVAL;
> @@ -144,13 +144,13 @@ static int pm860x_touch_dt_init(struct platform_device *pdev,
>  	if (data) {
>  		ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
>  		if (ret < 0)
> -			return -EINVAL;
> +			goto err_put_node;
>  	}
>  	/* set tsi prebias time */
>  	if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
>  		ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
>  		if (ret < 0)
> -			return -EINVAL;
> +			goto err_put_node;
>  	}
>  	/* set prebias & prechg time of pen detect */
>  	data = 0;
> @@ -161,10 +161,18 @@ static int pm860x_touch_dt_init(struct platform_device *pdev,
>  	if (data) {
>  		ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
>  		if (ret < 0)
> -			return -EINVAL;
> +			goto err_put_node;
>  	}
>  	of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
> +
> +	of_node_put(np);
> +
>  	return 0;
> +
> +err_put_node:
> +	of_node_put(np);
> +
> +	return -EINVAL;
>  }
>  #else
>  #define pm860x_touch_dt_init(x, y, z)	(-1)
> -- 
> 2.15.0
> 

-- 
Dmitry