Re: [PATCH v2] gpio: dwapb: fix NULL pointer dereference at dwapb_gpio_suspend()

From: Bartosz Golaszewski
Date: Mon Nov 30 2020 - 11:43:38 EST


On Fri, Nov 27, 2020 at 9:50 AM Luo Jiaxing <luojiaxing@xxxxxxxxxx> wrote:
>
> Following Calltrace is found when running echo freeze > /sys/power/state.
>
> [ 272.755506] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
> [ 272.755585] Call trace:
> [ 272.755587] dwapb_gpio_suspend+0x18/0x318
> [ 272.755588] pm_generic_suspend+0x2c/0x48
> [ 272.755595] acpi_subsys_suspend+0x60/0x70
> [ 272.755599] dpm_run_callback.isra.18+0x40/0xe0
> [ 272.755601] __device_suspend+0xf4/0x360
>
> The reason is platform_set_drvdata() is deleted, and dwapb_gpio_suspend()
> get *gpio by dev_get_drvdata().
>
> Fixes: feeaefd378ca ("gpio: dwapb: Use resource managed GPIO-chip add data method")
> Signed-off-by: Luo Jiaxing <luojiaxing@xxxxxxxxxx>
> Acked-by: Serge Semin <fancer.lancer@xxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
>
> ---
> v1->v2:
> 1. reduce calltrace log
> 2. delete blank line in tag block
> ---
> ---
> drivers/gpio/gpio-dwapb.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
> index 2a9046c..4275c18 100644
> --- a/drivers/gpio/gpio-dwapb.c
> +++ b/drivers/gpio/gpio-dwapb.c
> @@ -724,6 +724,8 @@ static int dwapb_gpio_probe(struct platform_device *pdev)
> return err;
> }
>
> + platform_set_drvdata(pdev, gpio);
> +
> return 0;
> }
>
> --
> 2.7.4
>

Applied, thanks!

Bartosz