Re: [PATCH] backlight: pcf50633: pdata may be a null pointer, null pointer dereference cause crash

From: Lee Jones
Date: Tue Feb 02 2021 - 03:29:42 EST


On Mon, 01 Feb 2021, Wenjia Zhao wrote:

Please provide a suitable commit messages.

Describe the problem.
Describe the issue was found.
Describe the solution.

> Signed-off-by: Wenjia Zhao <driverfuzzing@xxxxxxxxx>
> ---
> drivers/video/backlight/pcf50633-backlight.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/video/backlight/pcf50633-backlight.c b/drivers/video/backlight/pcf50633-backlight.c
> index 540dd338..43267af 100644
> --- a/drivers/video/backlight/pcf50633-backlight.c
> +++ b/drivers/video/backlight/pcf50633-backlight.c
> @@ -127,7 +127,8 @@ static int pcf50633_bl_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, pcf_bl);
>
> - pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDDIM, pdata->ramp_time);
> + if (pdata)
> + pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDDIM, pdata->ramp_time);

A tab should be 8 chars in Linux.

> /*
> * Should be different from bl_props.brightness, so we do not exit

--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
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