Public bug reported: To reproduce:
1. Install Xubuntu 16.04 LTS, update fully 2. Install packages xinetd, vnc4server 3. Append to /etc/services: vnc 5900/tcp # VNC Virtual Network Computing 4. Append to /etc/lightdm/lightdm.conf: [XDMCPServer] enabled=true 5. Create /etc/xinetd.d/vnc: service vnc { disable = no socket_type = stream protocol = tcp group = tty wait = no user = nobody server = /usr/bin/Xvnc server_args = -inetd -query localhost -once -securitytypes=none -geometry 1024x768 } # NOTE: might need to add an arg like ":1" to get out of way of local X server # my case is special as I am trying to run headless, nobody is logged in on console 6. Signal xinetd and lightdm to reconfigure: $ sudo killall -1 xinetd $ sudo service lightdm restart # or however your init system works 7. Don't know if significant (I am 400 miles away from test host and can't test): do NOT have anyone logged in on the test host console. In fact, to most closely reproduce my case, shut down the test host, power it off, disconnect all monitors and keyboards, then power it on and access from the net. 8. From another system, connect to the test host: $ gvncviewer testhost:0 # Your favorite VNC viewer & test host name... 9. VNC connects briefly, displays grey hashed background, disconnects. Syslog on test host says: Mar 29 15:07:40 osmium lightdm[13828]: (lightdm:13828): GLib-GObject-CRITICAL **: g_object_unref: assertion 'G_IS_OBJECT (object)' failed Mar 29 15:07:40 osmium systemd[1]: Started Session c11 of user lightdm. Mar 29 15:07:40 osmium lightdm[13828]: ** (lightdm:13828): WARNING **: Error activating login1 session: GDBus.Error:org.freedesktop.DBus.Error.NotSupported: Operation not supported Mar 29 15:07:40 osmium kernel: [14985.100699] lightdm-gtk-gre[13972]: segfault at 0 ip 00007f3f23bd09bf sp 00007ffc64b32058 error 4 in libc-2.23.so[7f3f23b3b000+1bf000] Mar 29 15:07:41 osmium lightdm[13828]: /etc/modprobe.d is not a file Mar 29 15:07:41 osmium lightdm[13828]: message repeated 4 times: [ /etc/modprobe.d is not a file] Mar 29 15:07:41 osmium lightdm[13828]: update-alternatives: error: no alternatives for x86_64-linux-gnu_gfxcore_conf and core-like-thing ends up in /var/crash/... ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: xorg 1:7.7+13ubuntu3 ProcVersionSignature: Ubuntu 4.4.0-70.91-generic 4.4.49 Uname: Linux 4.4.0-70-generic x86_64 NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia ApportVersion: 2.20.1-0ubuntu2.5 Architecture: amd64 CurrentDesktop: XFCE Date: Wed Mar 29 14:52:52 2017 InstallationDate: Installed on 2017-03-28 (1 days ago) InstallationMedia: Xubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719) ProcEnviron: TERM=xterm SHELL=/bin/bash PATH=(custom, no user) LANG=en_US.UTF-8 XDG_RUNTIME_DIR=<set> SourcePackage: xorg Symptom: display Title: Xorg crash UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: lightdm-gtk-greeter (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug crash xenial ** Package changed: xorg (Ubuntu) => lightdm-gtk-greeter (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1677397 Title: lightdm-gtk-greeter SIGSEGV when invoked by Xvnc -inetd -query To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm-gtk-greeter/+bug/1677397/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs