Re: [PATCH] pinctrl: mediatek: fix global-out-of-bounds issue

[Sean Wang]

HI, Zhiyong

On Wed, Nov 3, 2021 at 6:40 PM Zhiyong Tao <zhiyong.tao@xxxxxxxxxxxx> wrote:
>
> From: Guodong Liu <guodong.liu@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
>
> When eint virtual eint number is greater than gpio number,
> it maybe produce 'desc[eint_n]' size globle-out-of-bounds issue.
>
> Signed-off-by: Zhiyong Tao <zhiyong.tao@xxxxxxxxxxxx>
> Signed-off-by: Guodong Liu <guodong.liu@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> index 45ebdeba985a..9d57c897835c 100644
> --- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> +++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> @@ -286,7 +286,8 @@ static int mtk_xt_get_gpio_n(void *data, unsigned long eint_n,
>         *gpio_chip = &hw->chip;
>
>         /* Be greedy to guess first gpio_n is equal to eint_n */
> -       if (desc[eint_n].eint.eint_n == eint_n)
> +       if (((*gpio_chip)->ngpio > eint_n) &&

please use "hw->soc->npins > eint_n" to perform the boundary check to
be consistent with the other places for the same purpose

> +           desc[eint_n].eint.eint_n == eint_n)
>                 *gpio_n = eint_n;
>         else
>                 *gpio_n = mtk_xt_find_eint_num(hw, eint_n);
> --
> 2.25.1
>