On Wed, Jun 27, 2007 at 08:25:24AM -0400, Bill Nottingham wrote:
Miroslav Lichvar (mlichvar(a)redhat.com) said:
> > The entire idea of utempter is so that the terminal *doesn't* need to be
> > setgid - if it's setgid, what's the point of a helper?
>
> Well, the terminal doesn't need to be setgid utmp, but only utempter.
> Setgid utempter allows only adding/removing entries in utmp while
> setgid utmp allows unrestricted access.
Only if it's coded wrong (doesn't drop privs, etc.). By adding a
setgid to the binary, you're making the point of separating it
merely a code-sharing issue, as opposed to any huge security gains.
I'd remove the block on the directory - basically, you're intentionally
breaking user's environments for illusory security.
Ok, I've filed a bug report to drop the requirement in libutempter (#246063).
--
Miroslav Lichvar