Re: [PATCH v2] clk: rs9: Add clock index range check to rs9_of_clk_get()

[Geert Uytterhoeven]

Hi Marek,

On Wed, 21 Jan 2026 at 03:24, Marek Vasut <marek.vasut@xxxxxxxxxxx> wrote:
> On 1/20/26 10:05 AM, Geert Uytterhoeven wrote:
> > rs9_of_clk_get() does not validate the clock index in the passed
> > DT clock specifier.  If DT specifies an incorrect and out-of-range
> > index, this will access memory beyond the end of the clk_dif[] array.
> >
> > Fix by this adding a range check to rs9_of_clk_get().
> >
> > Fixes: 892e0ddea1aa6f70 ("clk: rs9: Add Renesas 9-series PCIe clock generator driver")
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > ---
> > This is v2 of "[PATCH] clk: rs9: Convert to clk_hw_onecell_data and
> > of_clk_hw_onecell_get()"
> > (https://lore.kernel.org/a6dce17b15d29a257d09fe0edc199a14c297f1a8.1768836042.git.geert+renesas@xxxxxxxxx)
> >
> > v2:
> >    - Just add the missing range check; the conversion to
> >      of_clk_hw_onecell_get() can be done later.
> > ---
> >   drivers/clk/clk-renesas-pcie.c | 3 +++
> >   1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/clk/clk-renesas-pcie.c b/drivers/clk/clk-renesas-pcie.c
> > index aa108df12e44fb9f..1adc5365ba1a3d59 100644
> > --- a/drivers/clk/clk-renesas-pcie.c
> > +++ b/drivers/clk/clk-renesas-pcie.c
> > @@ -277,6 +277,9 @@ rs9_of_clk_get(struct of_phandle_args *clkspec, void *data)
> >       struct rs9_driver_data *rs9 = data;
> >       unsigned int idx = clkspec->args[0];
> >
> > +     if (idx >= rs9->chip_info->num_clks)
>
> of_clk_src_onecell_get() does a pr_err("%s: invalid clock index %u\n",
> __func__, idx); on error, should this function do the same ?

I can add it if you want. But this function will (hopefully) be
short-lived anyway.
>
> > +             return ERR_PTR(-EINVAL);
> > +

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