locked out of system when upgrading to bionic from xenial

[Cyrus Harmon]

I was attempting to upgrade to bionic from xenial using do-release-upgrade but forgot to turn off screen locking. After an hour of inactivity, I ended up at the login screen but the keyboard won't allow me to enter keys in the login window and clicking the field results in a bizarre repeated "Failed to authenticate" message. See attached screenshot.

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DistroRelease: Ubuntu 18.04
InstallationDate: Installed on 2010-04-12 (2970 days ago)
InstallationMedia: Xubuntu 10.04 "Lucid Lynx" - Beta amd64 (20100406)
NonfreeKernelModules: nvidia_modeset nvidia
Package: lightdm 1.26.0-0ubuntu1
PackageArchitecture: amd64
ProcCpuinfoMinimal:
 processor : 3
 vendor_id : GenuineIntel
 cpu family : 6
 model : 42
 model name : Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz
 stepping : 7
 microcode : 0x25
 cpu MHz : 1689.366
 cache size : 6144 KB
 physical id : 0
 siblings : 4
 core id : 3
 cpu cores : 4
 apicid : 6
 initial apicid : 6
 fpu : yes
 fpu_exception : yes
 cpuid level : 13
 wp : yes
 flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm epb pti tpr_shadow vnmi flexpriority ept vpid xsaveopt dtherm ida arat pln pts
 bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass
 bogomips : 6219.77
 clflush size : 64
 cache_alignment : 64
 address sizes : 36 bits physical, 48 bits virtual
 power management:
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17
Tags: bionic
Uname: Linux 4.15.0-22-generic x86_64
UpgradeStatus: Upgraded to bionic on 2018-05-24 (5 days ago)
UserGroups: adm admin audio cdrom dialout lpadmin mythtv plugdev sambashare

[Daniel van Vugt (vanvugt)]

It appears you're still using lightdm that is not part of bionic.

It was part of xenial though, so that must be a leftover from the upgrade.

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Please execute the following command only once, as it will automatically gather debugging information, in a terminal:

apport-collect 1773268

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[Cyrus Harmon (ch-launchpad)]

Apport output attached.