Re: [PATCH] memstick: jmb38x_ms: Annotate struct jmb38x_ms with __counted_by

From: Ulf Hansson
Date: Tue Sep 26 2023 - 11:04:52 EST


On Fri, 22 Sept 2023 at 19:52, 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 jmb38x_ms.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Maxim Levitsky <maximlevitsky@xxxxxxxxx>
> Cc: Alex Dubov <oakad@xxxxxxxxx>
> Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Cc: Tom Rix <trix@xxxxxxxxxx>
> Cc: Len Baker <len.baker@xxxxxxx>
> Cc: Dan Carpenter <error27@xxxxxxxxx>
> Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
> Cc: linux-mmc@xxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Applied for next, thanks!

Kind regards
Uffe


> ---
> drivers/memstick/host/jmb38x_ms.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/memstick/host/jmb38x_ms.c b/drivers/memstick/host/jmb38x_ms.c
> index 21cb2a786058..e77eb8b0eb12 100644
> --- a/drivers/memstick/host/jmb38x_ms.c
> +++ b/drivers/memstick/host/jmb38x_ms.c
> @@ -66,7 +66,7 @@ struct jmb38x_ms_host {
> struct jmb38x_ms {
> struct pci_dev *pdev;
> int host_cnt;
> - struct memstick_host *hosts[];
> + struct memstick_host *hosts[] __counted_by(host_cnt);
> };
>
> #define BLOCK_COUNT_MASK 0xffff0000
> --
> 2.34.1
>