Re: [PATCH v6 1/3] random: add vgetrandom_alloc() syscall

From: Florian Weimer
Date: Wed Nov 23 2022 - 05:58:19 EST


* Jason A. Donenfeld:

> + * The vgetrandom() function in userspace requires an opaque state, which this
> + * function provides to userspace, by mapping a certain number of special pages
> + * into the calling process. It takes a hint as to the number of opaque states
> + * desired, and returns the number of opaque states actually allocated, the
> + * size of each one in bytes, and the address of the first state.
> + */
> +SYSCALL_DEFINE3(vgetrandom_alloc, unsigned long __user *, num,
> + unsigned long __user *, size_per_each, unsigned int, flags)

I think you should make this __u64, so that you get a consistent
userspace interface on all architectures, without the need for compat
system calls.

Thanks,
Florian