I think that given that align is a non zero const we can trust it.
Le ven. 17 mai 2024, 15:56, Gao Xiang <hsiang...@linux.alibaba.com> a
écrit :
> The following EROFS patch will use this helper to handle overflow
> ALIGN_UP() cases.
>
> Signed-off-by: Gao Xiang <hsiang...@linux.alibaba.com>
> ---
> include/grub/safemath.h | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/include/grub/safemath.h b/include/grub/safemath.h
> index fbd9b5925..baaea0ef4 100644
> --- a/include/grub/safemath.h
> +++ b/include/grub/safemath.h
> @@ -32,6 +32,22 @@
>
> #define grub_cast(a, res) grub_add ((a), 0, (res))
>
> +#define ALIGN_UP_OVF(v, align, res) \
> +({ \
> + bool __failed; \
> + typeof(v) a; \
> + \
> + __failed = grub_sub ((typeof(v))(align), 1, &a); \
> + if (__failed == false) \
> + { \
> + __failed = grub_add (v, a, res); \
> + if (__failed == false) \
> + { \
> + *(res) &= ~a; \
> + } \
> + } \
> +__failed;})
> +
> #else
> #error gcc 5.1 or newer or clang 8.0 or newer is required
> #endif
> --
> 2.39.3
>
>
_______________________________________________
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
