Re: [PATCH] power: supply: axp20x_ac_power: Annotate struct axp20x_ac_power with __counted_by

From: Gustavo A. R. Silva
Date: Sat Sep 23 2023 - 05:03:55 EST


On Fri, Sep 22, 2023 at 10:53:55AM -0700, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct axp20x_ac_power.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Sebastian Reichel <sre@xxxxxxxxxx>
> Cc: Chen-Yu Tsai <wens@xxxxxxxx>
> Cc: linux-pm@xxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Thanks
--
Gustavo

> ---
> drivers/power/supply/axp20x_ac_power.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/power/supply/axp20x_ac_power.c b/drivers/power/supply/axp20x_ac_power.c
> index 19a118633115..e5733cb9e19e 100644
> --- a/drivers/power/supply/axp20x_ac_power.c
> +++ b/drivers/power/supply/axp20x_ac_power.c
> @@ -45,7 +45,7 @@ struct axp20x_ac_power {
> struct iio_channel *acin_i;
> bool has_acin_path_sel;
> unsigned int num_irqs;
> - unsigned int irqs[];
> + unsigned int irqs[] __counted_by(num_irqs);
> };
>
> static irqreturn_t axp20x_ac_power_irq(int irq, void *devid)
> --
> 2.34.1
>
>