Re: /bin/su (was: CVE request -- coreutils -- tty hijacking possible in "su" via TIOCSTI ioctl)

[Ondrej Vasik <ovasik () redhat com>]

On Wed, 2011-06-15 at 09:49 +0200, Ludwig Nussel wrote:
> Bernhard Rosenkraenzer wrote:
> > On Friday, June 10, 2011 11:55 CEST, Ludwig Nussel <ludwig.nussel () suse de> wrote: 
> >  
> > > The issue also reminds me that there are several su implemenations.
> > > On Fedora and SUSE we have a patched coreutils version, Debian uses
> > > the one from shadow-utils and then there's also a su from
> > > SimplePAMApps, used by e.g. Owl. Of course each one has it's own
> > > quirks and weird features. Does anyone still remember why a
> > > particular implementation was chosen? :-)
> >
> >
> > In Ark Linux, we switched from the coreutils one to the shadow-utils one
> > about 2 years ago because the shadow-utils one does what we need (incl. PAM
> > support) without having to port the PAM patch on every new coreutils release.
>
> Upstream coreutils indicated that they consider su in coreutils kind
> of deprecated, basically only kept for legacy reasons on non-Linux
> OSes. They would accept the PAM patch though so distros don't need
> to maintain it.
>
> Is there actually any serious distro that doesn't use PAM though?
> Those #ifdefs to keep old shadow compatibility makes the code rather
> ugly and hard to read. Maybe it's time to just rip out the old code
> and submit a clean, PAM only su to util-linux.

For me, having it in coreutils, shadow-utils, SimplePAMApps and possibly
- in util-linux - could only cause a lot of confusion. Some
consolidation might be better.

Adding util-linux upstream maintainer to CC.

Greetings,
         Ondrej Vasik