Re: [PATCH] eeprom: at24: Annotate struct at24_data with __counted_by

From: Bartosz Golaszewski
Date: Mon Sep 25 2023 - 03:41:15 EST


On Fri, Sep 22, 2023 at 7:51 PM Kees Cook <keescook@xxxxxxxxxxxx> 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 at24_data.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Bartosz Golaszewski <brgl@xxxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: linux-i2c@xxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
> drivers/misc/eeprom/at24.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index af83aca452b7..7dfd7fdb423e 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -92,7 +92,7 @@ struct at24_data {
> * them for us.
> */
> u8 bank_addr_shift;
> - struct regmap *client_regmaps[];
> + struct regmap *client_regmaps[] __counted_by(num_addresses);
> };
>
> /*
> --
> 2.34.1
>

Applied, thanks!

Bart