Re: [PATCH 3/5] cxgb4: Annotate struct cxgb4_tc_u32_table with __counted_by

[Gustavo A. R. Silva]

On 9/29/23 20:11, 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 cxgb4_tc_u32_table.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Raju Rangoju <rajur@xxxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
>   drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h
> index f59dd4b2ae6f..9050568a034c 100644
> --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h
> +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h
> @@ -331,6 +331,6 @@ struct cxgb4_link {
>   
>   struct cxgb4_tc_u32_table {
>   	unsigned int size;          /* number of entries in table */
> -	struct cxgb4_link table[]; /* Jump table */
> +	struct cxgb4_link table[] __counted_by(size); /* Jump table */
>   };
>   #endif /* __CXGB4_TC_U32_PARSE_H */