Re: systemd fails to parse user that should run service

[Eric Blake <eblake () redhat com>]

On 07/05/2017 03:50 AM, Pali Rohár wrote:
> There are basically two problems:
>
> 1) In more Linux distributions useradd tool allow to create a new user
> which starts with digit. Also according to POSIX such user name is a
> valid. This means that valid user name (for some Linux distributions)
> from /etc/passwd specified in systemd unit file results running service
> as root user.

In fact, it is possible to create a username of '0' which is a non-root
user.  GNU Coreutils has several tools that support a lookup of '+0' to
force a numeric uid interpretation (get information related to uid 0,
regardless of whether there is also a username "0"), while omitting the
leading + does a username lookup first then falls back to a uid, since
leading + is not a valid POSIX username start character.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

Attachment: signature.asc
Description: OpenPGP digital signature