error in commented-out NAME_REGEX

[Peter Abeln]

The default /etc/adduser.conf contains the line:

    #NAME_REGEX="^[a-z][-.a-z0-9_]*\$"

Commenting this out in preparation of updating it does not work as expected:

    pra@PABELN-X1E:~$ grep NAME_REGEX /etc/adduser.conf; sudo adduser testuser
    NAME_REGEX="^[a-z][-a-z0-9_]*\$"
    adduser: Please enter a username matching the regular expression configured
    via the NAME_REGEX[_SYSTEM] configuration variable. Use the `--force-badname'
    option to relax this check or reconfigure NAME_REGEX.
    pra@PABELN-X1E:~$

This is due to the overeager escaping of the dollar sign, which has the undesired effect of requring that usernames end in `$`:

    pra@PABELN-X1E:~$ sudo adduser testuser$
    Adding user `testuser$' ...
    Adding new group `testuser$' (1002) ...
    Adding new user `testuser$' (1002) with group `testuser$' ...
    Creating home directory `/home/testuser$' ...
    Copying files from `/etc/skel' ...
    New password:

Removing the backslash escaping the terminal `$` corrects the issue:

    pra@PABELN-X1E:~$ grep NAME_REGEX /etc/adduser.conf; sudo adduser testuser
    NAME_REGEX="^[a-z][-a-z0-9_]*$"
    Adding user `testuser' ...
    Adding new group `testuser' (1002) ...
    Adding new user `testuser' (1002) with group `testuser' ...
    Creating home directory `/home/testuser' ...
    Copying files from `/etc/skel' ...
    New password:

I reported this for the `adduser` package because it seemed the closest match. The file /etc/adduser.conf is not owned by any package.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: adduser 3.118ubuntu5
Uname: Linux 5.10.102.1-microsoft-standard-WSL2 x86_64
ApportVersion: 2.20.11-0ubuntu82.1
Architecture: amd64
CasperMD5CheckResult: unknown
Date: Thu Jul 21 19:56:02 2022
PackageArchitecture: all
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: adduser
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Benjamin Drung (bdrung)]

Fixed in Debian release 3.119: https://salsa.debian.org/debian/adduser/-/commit/3982734b7cea35182b15b23945816ce42c001619

[Benjamin Drung (bdrung)]

Thanks for reporting this bug. Reporting it against adduser was correct, since adduser creates and manages /etc/adduser.conf

[Benjamin Drung (bdrung)]

Fixed in adduser 3.129ubuntu1 in Ubuntu 23.04 (lunar).