screen -ls displays incorrect dates and times for existing sessions

[Stephen Bosch]

Consider the following output:

380639.pts-1.host user@host 2024-01-23 13:09:12 ~ $ screen -ls
There are screens on:
        380639.pts-1.host (11.02.2024 07:05:02) (Attached)
1 Socket in /run/screen/S-user.
 380639.pts-1.host user@host 2024-01-23 13:09:33 ~ $ LANG=C date
Tue Jan 23 13:09:42 UTC 2024
 380639.pts-1.host user@host 2024-01-23 13:09:42 ~ $

1. Ubuntu version
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04.3 LTS"

2. Package version
$ LANG=C apt-cache policy screen
screen:
  Installed: 4.9.0-1
  Candidate: 4.9.0-1
  Version table:
 *** 4.9.0-1 500
        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
        100 /var/lib/dpkg/status

3. I expect creation dates for screen sessions listed via screen -ls to be in the past and to be accurate.

4. screen -ls dates are in the future.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: screen 4.9.0-1
ProcVersionSignature: Ubuntu 5.4.0-169.187-generic 5.4.257
Uname: Linux 5.4.0-169-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
CasperMD5CheckResult: unknown
CloudArchitecture: x86_64
CloudID: lxd
CloudName: lxd
CloudPlatform: lxd
CloudSubPlatform: LXD socket API v. 1.0 (/dev/lxd/sock)
Date: Tue Jan 23 12:44:59 2024
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=de_DE.utf8
 SHELL=/bin/bash
SourcePackage: screen
UpgradeStatus: No upgrade log present (probably fresh install)

[Sergio Durigan Junior (sergiodj)]

Thanks for taking the time to report a bug.

I've confirmed the problem locally. I have also noticed that the Debian package (which is where Ubuntu's screen comes from) carries its own patch to calculate session creation time. This is probably an issue with that patch, although I haven't tested other distros.

I opened a bug against the Debian package. Meanwhile, I'll set this one as Triaged and with a low priority.

Thank you.

[Stephen Bosch (omnicorn)]

I'm relieved you were able to reproduce it.

What I don't understand is that not all my Jammy containers exhibit this behaviour with screen. I wonder what it is about this specific instance that triggers this bug.

Do you have any insight into the mechanism?

[Athos Ribeiro (athos-ribeiro)]

> I wonder what it is about this specific instance that triggers this bug.

This would require further analysis of the patch mentioned by Sergio (and possibly more info on your setup). FWIW, it would be nice to provide such additional information in the Debian bug filed by Sergio so the Debian maintainers can get more context on the issue.