If you maintain widely-used software, you're going to get a lot of bug reports which are in fact user error, and you don't have a great deal of time to spend on each report.
So it's easy to mistakenly dismiss a report when it contains at least one user error, or even something close to a user error, even when it also exposes a real bug.
(It's less forgivable to continue being loudly wrong once other people have pointed out real problems more clearly.)
Yes, that might be true. I never complained about him before "in public" so there was some steam to release. However I hope I still gave enough clear thought on how I think he is acting wrong repeatedly.
Which only makes it worse. There is a good deal of serious replies to the issue, but because of some trolling, the whole discussion is considered invalid by the maintainers, or at least they make it look like that by just closing it without any further comment. Only about an hour ago did poettering reply again giving some more insight, but the damage has been done and next time there will probably be even more trolling.
I'm not sure if POSIX has any relevance here. Afaik systemd isn't claiming any sort of POSIX compliance, nor is it targeting POSIX systems in general, in fact it is explicitly Linux-only.
Similarly they will retain previously introduced, but flawed, interfaces etc until they are damn sure that they are no longer in use.
It’s a mindset/philosophy problem, and that doesn’t change when bugs get fixed. It would require the devs to change, but that didn’t happen in the past decade, so we cannot just assume that it will happen in the next.
What is going on here is that an admin thinks he has shored up the service defined in the service file, because hey, it runs. Only to later have the server 0wned because apparently it was running as root the whole time...
EDIT: No; it acts as if the 'User=' directive doesn't exist.
On the other hand, you come here to uselessly complain and have the temerity to complain that poettering doesn't write exactly the code you want him to write.
How do you justify your ridiculous attitude?
No, apparently I'm not. In the thread I read, OP mentioned a regex that he found somewhere on the internet, and poettering just confirms it would be invalid. No references who says it's invalid or where to look up the definition. Nothing. Also no mention of the "default to root" issue in his post, which clearly could be considered a security issue as mentioned in several comments on the issue and here in the comments. He says config options are validated to prevent mistakes, but doesn't give any insight why anyone would consider default to root a sane fallback. You call that "explaining precisely"?
I gave examples of his contradictory behaviour regarding usability and dangerous pitfalls while claiming systemd would be elegant and easy to use. I'm not complaining he doesn't write code I want, I'm complaining he doesn't practice what he preaches and--as stated by the very first phrase of my comment--to explain why it doesn't come as much of a surprise to me he gets so much hate.
I've been working with systemd since late 2012 and like a lot of its ideas and concepts, but the way this guy deals with bug reports and people is just horrible.
Oh well, guess I just fed the troll by replying.
systemd rejects usernames starting with a digit even though they exist in the wild;
systemd ignores config lines containing values it considers invalid, rather than failing the whole unit;
systemd defaults User to root, rather than making User required.
Any of those might be defensible on their own, but the combination is horrid.
We can argue if User= lines should be validated more carefully or cause hard errors (vs warnings), but if you do not provide a valid User= line, the process will spawn with the current uid (which is 0 for initd).
Many of my services do not run as root for a reason.
Indeed, and once that was pointed out his response was equally polite and accurate, offering a workaround which keeps everyone happy.
Literally, what more do people expect?
While understandable (maintainers are busy people and likely have to deal with a lot of reports that have clear cut answers), it sadly fits into the image people have of them.
I personally think "thumbs down" (since you referenced those) is a completely valid response to that – but to be clear, posting insults or other attacks is not!
You're running a SaaS which spawns restricted demons/containers per customer, separating the users by assigning them local user accounts. One day, user "0zero" registers and their account has access to your whole environment. Would you expect this? Would you not classify this as a security issue?
root # chpst -u 0zero id
uid=1462(0zero) gid=1481(0zero) groups=1481(0zero)
root # setuidgid 0zero id
uid=1462(0zero) gid=1481(0zero) groups=1481(0zero)
root # chpst -u 0day id
chpst: fatal: unable to get password/group file entry: file does not exist
root # setuidgid 0day id
setuidgid: FATAL: 0day: No such user.
... as is documented in their user manuals, resulting in ...
root # system-control convert-systemd-units ./0day.service
root # install -d /home/0day
root # ln -s /etc/service-bundles/services/sysinit-log 0day/log
root # system-control start 0day
root # system-control status 0day
State : failed since 2017-07-02 11:14:17 +0100; 0s ago
Main PID: 80083
Started: exit 0 at 2017-07-02 11:13:35 +0100; 42s ago
Ran: exit 111 at 2017-07-02 11:14:17 +0100; 0s ago
Config : enabled
2017-07-02 11:14:17.130870725 setuidgid: FATAL: 0day: No such user.
2017-07-02 11:14:17.247334398 setuidgid: FATAL: 0day: No such user.
2017-07-02 11:14:17.363857132 setuidgid: FATAL: 0day: No such user.
2017-07-02 11:14:17.481175128 setuidgid: FATAL: 0day: No such user.
2017-07-02 11:14:17.598958702 setuidgid: FATAL: 0day: No such user.
A 0day is supposed to get you root access, so behaviour is working as expected.
If you define "usernames starting with numbers" as invalid, and then define the behaviour of unit files with a user directive containing an invalid user to run as root, then the behaviour is as expected, and is not a bug.
The fact the software doesn't do what any sensible user would expect is completely irrelevant to it being a "bug" or not.
[edit: removed dig at poettering]
Logs and error and continues? I think you're confused by Systemd exposing all sorts of frailties of traditional software. How do you propose that it differentiate between UIDs and user names?
That's not the problem, though. The problem is that systemd encounters a username setting, and the workaround decided upon was that if you find an explicitly stated username setting, that the best thing to do in the case of that explicity stated username being something you consider invalid (despite it being completely valid on the largest platform you target) is to throw that statement away and proceed as the highest privileged user on the system, even though the very intent of the username setting is often to restrict privileges. It tells you about it in a log file, though, that you'll definitely see before it's too late!
Even that poorly thought out situation being the status quo isn't the problem. The problem is refusing to consider that this is perhaps not the best workaround, prior to this workaround becoming a de facto standard embedded by practice.
This isn't an us-versus-them thing. It's not about being combative or saying that anyone is wrong or bad. It's about looking for continual improvement.
Maybe follow GNU coreutils, prefix ids with +
It's something that has to be picked, and the parent poster will undoubtedly count as 'arrogance' for choosing a workaround.
Make User= only accept input that starts with a character.
Add another option for Uid= that would only accept numeric digits.
Why he said 0day not valid user?
I create '0day' user on my computer without problem (Fedora 26 Beta, Debian 9)
$ id 0day
uid=1003(0day) gid=1003(0day) groups=1003(0day)
I don't think systemd (which is after all attempting to be universally deployed) is entitled to assume that the system administrator hasn't changed the default.
Systemd is running something as root because it doesn't like something in configuration file, instead of returning error or running it under the correct user. That's a huge WTF and a possible security issue, but alas. Systemd doesn't make mistakes and everything is someone elses fault.
They've had to delete multiple posts from the thread which are nothing but trolls, hell YOUR post is nothing but a troll.
Tempted to label it as a ripple effect of the rising SJW element in FOSS, because both terms seems to attract that group in defense of the shouter without concern for context.
nobody is not a suitable account for running daemons as. It has a very specific purpose, originating in NFS. That purpose is to be the visible owner of files and directories in mounted NFS filesystems in certain circumstances. Daemon processes in general run as unprivileged accounts that should own a minimal amount of filesystem entities relevant to their operation. They certainly should not run as accounts that own vast tracts of the filesystem that the daemon programs have no business dealing in.
For best results, a daemon process that has dropped privileges should run under the aegis of an unprivileged account that is a rôle account specific to that one service. This allows one to grant filesystem access and object ownership specifically, and enables the kernel's usual mechanisms for preventing other (unprivileged) processes from messing with the daemon process with the likes of ptrace() and kill().
And if the account given as the one to drop privileges to does not exist in the user account database and is invalid, the service should fail to run.
This is what daemontools-family service management does; because setuidgid (or runuid, or chpst, or whatever) abends with a fatal error when it fails to find the account in the system's account database. This is what the Solaris SMF does, too. It switches the service to the "maintenance" state when the "user" property for the method context is wrong:
Nov 12 22:24:17 aocdbs02a inetd: Property 'user' of instance svc:/network/stdiscover:default is missing, inconsistent or invalid
Nov 12 22:24:17 aocdbs02a inetd: Invalid configuration for instance svc:/network/stdiscover:default, placing in maintenance
If you can’t see the irony of granting the services of that user root access, have a look at the imprint (the owner of that domain).