Bug#718628: Cannot login as different user after accidentally selecting the wrong name

[musbur at posteo.at]

Package: gdm3
Version: 3.4.1-9
Severity: important

Dear Maintainer,

it seems that gdm3 doesn't recover from a wrong user selection on the
login screen. The only way for a non-root and system-savvy user is
a complete reboot. I'm writing this from the perspective of my wife
and kids. My kids wouldn't even be able to find the reboot option.
From this perspective this bug rates "important" because it effectively
brings down the system.

*** Please consider answering these questions, where appropriate ***

   * What led up to the situation?

   Normal boot-up of the system, gdm3 login window showing with user
   list.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?
    
    Selecting a wrong user name from the list, and subsequently clicking
    "Cancel" hoping to get back to the initial screen with the full user
    list displayed

   * What was the outcome of this action?

    User display window collapses to a thin blue horizontal line, and
    after hitting "Enter" gdm3 keeps asking the password for the wrong
    user, with no way of selecting the correct user.

   * What outcome did you expect instead?

   Coming back to the initial login screen.

*** End of the template - remove these lines ***


-- System Information:
Debian Release: jessie/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)

Kernel: Linux 3.9-1-686-pae (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages gdm3 depends on:
ii  accountsservice                             0.6.34-1
ii  adduser                                     3.113+nmu3
ii  dconf-gsettings-backend                     0.16.1-1
ii  dconf-tools                                 0.16.1-1
ii  debconf [debconf-2.0]                       1.5.50
ii  gir1.2-freedesktop                          1.36.0-2+b1
ii  gir1.2-glib-2.0                             1.36.0-2+b1
ii  gnome-session [x-session-manager]           3.4.2.1-4
ii  gnome-session-bin                           3.4.2.1-4
ii  gnome-session-fallback [x-session-manager]  3.4.2.1-4
ii  gnome-settings-daemon
3.4.2+git20121218.7c1322-6+b1 ii  gnome-terminal
[x-terminal-emulator]        3.8.3-1 ii
gsettings-desktop-schemas                   3.4.2-3 ii
libaccountsservice0                         0.6.34-1 ii
libatk1.0-0                                 2.8.0-2 ii
libattr1                                    1:2.4.47-1 ii
libaudit0                                   1:1.7.18-1.1 ii
libc6                                       2.17-7 ii
libcairo-gobject2                           1.12.14-4 ii
libcairo2                                   1.12.14-4 ii
libcanberra-gtk3-0                          0.30-2 ii
libcanberra0                                0.30-2 ii
libdbus-1-3                                 1.6.12-1 ii
libdbus-glib-1-2                            0.100.2-1 ii
libfontconfig1                              2.10.2-2 ii
libgdk-pixbuf2.0-0                          2.28.2-1 ii
libglib2.0-0                                2.36.3-3 ii
libglib2.0-bin                              2.36.3-3 ii
libgtk-3-0                                  3.8.2-3 ii
libpam-modules                              1.1.3-9 ii
libpam-runtime                              1.1.3-9 ii
libpam0g                                    1.1.3-9 ii
libpango-1.0-0                              1.32.5-5+b1 ii
libpangocairo-1.0-0                         1.32.5-5+b1 ii
librsvg2-common                             2.36.4-2 ii
libselinux1                                 2.1.13-2 ii
libupower-glib1                             0.9.20-2 ii
libwrap0                                    7.6.q-24 ii
libx11-6                                    2:1.6.0-1 ii
libxau6                                     1:1.0.8-1 ii
libxdmcp6                                   1:1.1.1-1 ii
libxklavier16                               5.2.1-1 ii
libxrandr2                                  2:1.4.1-1 ii
lsb-base                                    4.1+Debian12 ii  lxsession
[x-session-manager]               0.4.6.1-4 ii  lxterminal
[x-terminal-emulator]            0.1.11-4 ii  metacity
[x-window-manager]                 1:2.34.13-1 ii  openbox
[x-window-manager]                  3.5.0-7 ii
policykit-1-gnome                           0.105-2 ii  rxvt-unicode
[x-terminal-emulator]          9.18-2 ii
upower                                      0.9.20-2 ii
x11-common                                  1:7.7+3 ii
x11-xserver-utils                           7.7~3 ii  xfce4-session
[x-session-manager]           4.10.1-1 ii  xfwm4
[x-window-manager]                    4.10.1-1

Versions of packages gdm3 recommends:
ii  at-spi2-core               2.9.4-1
ii  desktop-base               7.0.3
ii  gnome-icon-theme           3.8.2-2
ii  gnome-icon-theme-symbolic  3.8.2.2-2
ii  x11-xkb-utils              7.7~1
ii  xserver-xephyr             2:1.12.4-6
ii  xserver-xorg               1:7.7+3
ii  zenity                     3.8.0-1

Versions of packages gdm3 suggests:
pn  gnome-orca            <none>
ii  gnome-shell           3.4.2-11
ii  libpam-gnome-keyring  3.8.2-2

-- Configuration Files:
/etc/gdm3/daemon.conf changed:
[daemon]
[security]
[xdmcp]
[greeter]
[chooser]
[debug]


-- debconf information:
* shared/default-x-display-manager: gdm3
  gdm3/daemon_name: /usr/sbin/gdm3