Re: [PATCH v10 3/4] random: introduce generic vDSO getrandom() implementation

Florian Weimer
2022-11-30T10:44:42Z

* Jason A. Donenfeld:

> diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
> index 73eb622e7663..9ae4d76b36c7 100644
> --- a/include/vdso/datapage.h
> +++ b/include/vdso/datapage.h
> @@ -109,6 +109,16 @@ struct vdso_data {
> struct arch_vdso_data arch_data;
> };
>
> +/**
> + * struct vdso_rng_data - vdso RNG state information
> + * @generation: a counter representing the number of RNG reseeds
> + * @is_ready: whether the RNG is initialized
> + */
> +struct vdso_rng_data {
> + unsigned long generation;
> + bool is_ready;
> +};
> +

I don't think you can use a type like long here. The header says this:

* vdso_data will be accessed by 64 bit and compat code at the same time
* so we should be careful before modifying this structure.

So the ABI must be same for 32-bit and 64-bit mode, and long isn't.

Thanks,
Florian