Re: [PATCH] pinctrl: renesas:fix possible null pointer dereference struct pinmux_range *

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Alex,

Thanks for your patch!

On Sun, Feb 7, 2021 at 4:08 PM <alex_luca@xxxxxxx> wrote:
> From: Zhang Kun <zhangkun@xxxxxxxxxx>
>
> The parameters of  sh_pfc_enum_in_range() pinmux_range *r should be checked
> first for possible null ponter, especially when PINMUX_TYPE_FUNCTION as the
> pinmux_type was passed by sh_pfc_config_mux().

If pinmux_type in sh_pfc_config_mux() is PINMUX_TYPE_FUNCTION or
PINMUX_TYPE_GPIO, range is indeed NULL.
But as the call

    in_range = sh_pfc_enum_in_range(enum_id, range);

is not done in case of these pinmux types, I don't see where the
problem is.  What am I missing?

> Signed-off-by: Zhang Kun <zhangkun@xxxxxxxxxx>

As you picked up a patch from Zhang, you should add your own SoB here.

> --- a/drivers/pinctrl/renesas/core.c
> +++ b/drivers/pinctrl/renesas/core.c
> @@ -128,6 +128,9 @@ int sh_pfc_get_pin_index(struct sh_pfc *pfc, unsigned int pin)
>
>  static int sh_pfc_enum_in_range(u16 enum_id, const struct pinmux_range *r)
>  {
> +       if (!r)
> +               return 0;
> +
>         if (enum_id < r->begin)
>                 return 0;

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds