Bug#673102: gdm3 greeter shows ALL users with non-/bin/false shells

[sacrificial-spam-address at horizon.com]

Package: gdm3
Version: 3.0.4-4
Severity:important
Architecture: i386

I'm tracking debian/unstable, and my computer was down for a week or so
with a bad power supply.  After bringing it up to date, I found a stupid
number of users listed in the gdm3 greeter.

Users like "backup", "Majordomo" (ud 31), gnats (uid 41), etc.

This is, if I understand correctly, Not Supposed To Happen.

Changing shells to /bin/false makes users disappear from the list,
but /bin/symlink-to-bash does not.

System is 64-bit kernel, i386 userland, 16 GB RAM, i7-2700K processor,
3.3.0-rc5 kernel (upgrading soon), onboard (Intel HD 3000) graphics.

The bug might not be in the gdm3 binary proper, but rather one of the
support libraries, but I'm not up to figuring out what is going on.
gdm3 is ultimately responsible.


Attempts to specify only listed users in /etc/gdm3/daemon.comf,
section [greeter], using IncludeAll=false and Include="user,user2"
did not work.  Nor did Exclude="majordomo".

Neither did equivalent edits to /usr/share/gdm/gdm.schemas.