Re: [PATCH RFC v2] fhandle: expose u64 mount id to name_to_handle_at(2)

[hch@xxxxxxxxxxxxx]

On Wed, May 29, 2024 at 09:25:49AM +1000, Dave Chinner wrote:
> But no-one has bothered to reply or acknowledge my comments so I'll
> point them out again and repeat: Filehandles generated by
> the kernel for unprivileged use *must* be self describing and self
> validating as the kernel must be able to detect and prevent
> unprivelged users from generating custom filehandles that can be
> used to access files outside the restricted scope of their
> container.

We must not generate file handle for unprivileged use at all, as they
bypass all the path based access controls.