cannot add a user with username beginning with a number

[Josep Lladonosa Capell]

The GUI to add a user in Ubuntu allows a username beginning with a number
(checked appears ok but call to user creation fails).
The reason is that the called Perl script adduser does not accept it. This script is configurable in /etc/adduser.conf:

# check user and group names also against this regular expression.
#NAME_REGEX="^[a-z][-a-z0-9_]*\$"

As it is commented out, (same) value is taken from /usr/share/perl5/Debian/AdduserCommon.pm:

$configref->{"name_regex"} = "^[a-z][-a-z0-9_]*\$";

To solve this, you could:

- validate only names matching the expression.

- modify /etc/adduser.conf with another NAME_REGEX to fit Ubuntu's policies
(in this case, adduser would be affected, too).

Added to this, in a root terminal, adduser/passwd allow any password.
This GUI limits this possibility (for security matters, that is ok, but IMHO user creating an account from GUI should behave "like root").

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gnome-control-center 1:3.28.2-0ubuntu0.18.04.6
ProcVersionSignature: Ubuntu 5.3.0-42.34~18.04.1-generic 5.3.18
Uname: Linux 5.3.0-42-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.12
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Fri Apr 24 11:59:24 2020
ExecutablePath: /usr/bin/gnome-control-center
InstallationDate: Installed on 2020-03-10 (45 days ago)
InstallationMedia: Ubuntu 18.04.4 LTS "Bionic Beaver" - Release amd64 (20200203.1)
SourcePackage: gnome-control-center
UpgradeStatus: No upgrade log present (probably fresh install)

[Sebastien Bacher (seb128)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1630417, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.