Bdtyktl

BUG: Ubuntu Server 18.04.1 LTS tty1 "Login Incorrect"
Userspace break as a result of missing patch backport

As I understand the bug: upgrading the kernel has introduced a bug which has made it impossible to enter a password and log in.

Solutions:

1. 
   

   Move back to previous kernel:

   
   
   

   sudo apt install linux-{image,headers,modules,modules-extra}-4.15.0-43-generic
   
   

   
   



2. Move forward to kernel 4.18.0-15-generic using Linux commands.

Problem: How can I access my home Web Server when I am unable to log in to the terminal screen? I can manage Linux files using FileZilla on a Windows PC but have not set up sshd (PUTTY) to run Linux commands.

Any suggestions please?

Ur solution (2) would work fine, but consider using ssh meanwhile if you need canonical live patching, i would rather stay at 4.15.0-45, it should be fixed pretty soon:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813873/comments/29

If you configured FileZilla with sftp, ssh will most likely work with PuTTY, use same port and credentials.

Ubuntu 18.04.1 LTS Server (GNU/Linux 4.15.0-45-generic x86_64)
"Login Incorrect" repeated four times after entering user name.
"Userspace break as a result of missing patch backport"
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813873
three kernels installed 4.15.0.39 4.15.0.44 4.15.0.45-generic.
Is there a safe replacement for 4.15.0.45-generic?

-------- Forwarded Message --------
Subject: Re: Ubuntu 18.04.1 LTS Server
Date: Mon, 18 Feb 2019 11:38:32 +0100
From: Guilherme Piccoli
To: Kevin & Pauline Gordon
CC: ubuntu-server@lists.ubuntu.com

Hi, the kernel with this fix for Bionic is present in the -proposed repository,
the version is 4.15.0-46-generic. To enable proposed packages, you
can check [0].

Alternatively, you can install version 4.15.0-43-generic, which does not
have the offending patches that caused the tty issue.

Cheers,
Guilherme

QUESTION: To return to a normal stable Ubuntu Server what commands should I use?
I have three kernels installed 4.15.0.39 4.15.0.44 4.15.0.45-generic.
I have no graphical interface. I do not see a grub menu during boot-up.
There are further problems with 4.15.0-46-generic so I would like to install 4.15.0-43-generic. Can I have four kernels installed? What is the best apt-get syntax for this? Can I use commands to set a boot-up preference to 4.15.0-43-generic? I am seeking advice for my Ubuntu 18.04.1 LTS Server which was "stable" and I need it to be as near stable as possible now and in the future.

I used the following commands in this order:

sudo apt install linux-{image,headers,modules,modules-extra}-4.15.0-43-generic

sudo apt-mark hold linux-*-4.15.0-4[45]-generic

sudo apt remove linux-*-4.15.0-4[45]-generic

I then reboot and uname -a confirmed the default kernel is linux-4.15.0-43-generic