Re: [PATCH 1/2] gpio: mt7621: report failure of devm_kasprintf()

[Bartosz Golaszewski <brgl@xxxxxxxx>]

śr., 21 lis 2018 o 19:13 Nicholas Mc Guire <hofrat@xxxxxxxxx> napisał(a):
>
> kasprintf() may return NULL on failure of internal allocation thus the
> assigned  label  is not safe if not explicitly checked. On error
> mediatek_gpio_bank_probe() returns negative values so -ENOMEM in the
> (unlikely) failure case should be fine here.
>
> Signed-off-by: Nicholas Mc Guire <hofrat@xxxxxxxxx>
> Fixes: 4ba9c3afda41 ("gpio: mt7621: Add a driver for MT7621")
> ---
>
> V2: The dev_err() for the unlikely case of the devm_kasprintf()
>     failing was removed on request from Bartosz Golaszewski
>     <bgolaszewski@xxxxxxxxxxxx>
>
> Problem located with experimental coccinelle script
>
> Patch was compile tested with: omega2p_defconfig, SOC_MT7621=y,
> GPIOLIB=y, GPIO_MT7621=y
>
> Patch is against 4.20-rc3 (localversion-next is next-20181121)
>
>  drivers/gpio/gpio-mt7621.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c
> index d72af6f..1ec95bc 100644
> --- a/drivers/gpio/gpio-mt7621.c
> +++ b/drivers/gpio/gpio-mt7621.c
> @@ -244,6 +244,8 @@ mediatek_gpio_bank_probe(struct device *dev,
>         rg->chip.of_xlate = mediatek_gpio_xlate;
>         rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d",
>                                         dev_name(dev), bank);
> +       if (!rg->chip.label)
> +               return -ENOMEM;
>
>         ret = devm_gpiochip_add_data(dev, &rg->chip, mtk);
>         if (ret < 0) {
> --
> 2.1.4
>

Reviewed-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>