On Tue, Jun 26, 2007 at 06:26:39PM -0400, Bill Nottingham wrote:
Miroslav Lichvar (mlichvar(a)redhat.com) said:
> The problem is that setgid binaries have some environment variables
> like LD_LIBRARY_PATH and TMPDIR removed. I got bugs #229360 #243069
> reported for xterm. Unfortunately I can't fix it unless utempter is
> accessible without setgid. Do we really need to protect the file from
> bad applications?
>
> Gnome-terminal, on the other hand, uses gnome-pty-helper binary that
> has utmp setgid. The binary is not hidden and every application can
> make entries in the utmp file.
>
> To have some consistency, either gnome-pty-helper needs to be also
> made accessible only to the utempter group and gnome-terminal is made
> setgid or utemper is made accessible to everyone and xterm drops setgid.
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.
The question is, should users be allowed to add entries in utmp
without starting a terminal emulator?
--
Miroslav Lichvar