Re: [RCF] [PATCH] unprivileged mount/umount

Miklos Szeredi
2005-05-11T21:26:19Z

> This is not a proposal - I'm not saying it's pretty - but a suggestion
> that you can use today.
>
> Use clone(), and then have the child task open "/" and pass that file
> descriptor back to the parent process using a unix socket. The child
> can exit and the parent can use the new namespace how it likes. Short
> and sweet, and you can create as many namespaces as you like :)
>
> That's mkdir done.

Right.

> You can't do a lot with the new namespace, because of the security
> restrictions on mount() on a foreign namespace. That's what I meant
> about the "small fixes" - get rid of the current->namespace checks and
> it'll be usable.
>
> I don't see the purpose of current->namespace and the associated mount
> restrictions at all. I asked Al Viro what it's for, but haven't seen
> a reply :( IMHO current->namespace should simply be removed, because the
> "current namespace" is represented just fine by
> current->fs->rootmnt->mnt_namespace.

I'll look at what it would take to remove current->namespace.

Miklos