Re: [PATCH v2 0/6] unshare: Add support for mapping ranges of user/group IDs

[Daniel Gerber <dg@atufi.org>]

2022-01-14, Sean Anderson:
> It's stack garbage. Try
>
> diff --git i/sys-utils/unshare.c w/sys-utils/unshare.c
> index 3cdd90329..5ac7af3de 100644
> --- i/sys-utils/unshare.c
> +++ w/sys-utils/unshare.c
> @@ -385,10 +385,10 @@ struct map_range {
>   */
>  static int uint_to_id(const char *name, size_t sz)
>  {
> -       char buf[UID_BUFSIZ];
> +       char buf[UID_BUFSIZ] = {0};
>  -       mem2strcpy(buf, name, sz, sizeof(buf));
> -       return strtoul_or_err(name, _("could not parse ID"));
> +       memcpy(buf, name, min(sz, sizeof(buf) - 1));
> +       return strtoul_or_err(buf, _("could not parse ID"));
>  }
>    /**

That works, thanks.


> > Also, I would suggest adopting the same argument order as in /proc/<pid>/uid_map and newuidmap -- inner,outer,count.

> I think this is a rather silly order. Since this is a mapping, the "natural" order is

> outer -> inner

> and only from the new namespace's PoV is it

> inner -> outer

> It certainly helped me remember things once I reversed the order...

All right, this may make some sense to me now. To the user discovering these tools though (me yesterday) the worst is missing one "standard" notation...

> > This doc string has it reversed:

> As noted above, this is intended.

> >   * struct map_range - A range of IDs to map
> >   * @outer: First ID inside the namespace
> >   * @inner: First ID outside the namespace

I mean "@outer: First ID inside ..." surely is a typo, isn't it?


Best,

Daniel