6 ms·

Systemd’s “usernames that start with digit get root privileges” bug

55 points by Mojah 9y ago

notacoward 9y ago
To me, this reflects as much on "many eyes make all bugs shallow" as on systemd. How many have used this feature without noticing that it has a serious bug? How many pairs of eyes have even passed over that particular piece of code without seeing what was wrong with it? More eyes only make bugs shallow when they're trained and diligent eyes.
udsloiwdaa 9y ago
/. is gonna have a field day.
- digi_owl 9y ago
  Nah, the bots will make sure the pro views get all the insightful votes...
moe 9y ago
Systemd is the disaster that happens when we ignore the lessons of UNIX. UNIX is all about small, composable tools. Do one job and do it well. One of these tools didn't stand up to the test of time (SysV init) and needed to be replaced. We could have chosen one of the mature candidates (upstart, runit, minit) or even built a great new one from scratch. Life would have been good. But instead we ended up with this trainwreck of a monolith that not only replaced init, but at the same time tried to reinvent almost every critical userspace daemon from Syslog to NTP. It predictably failed on every metric. Now it is time for the major Linux distributions to conclude this experiment, roll back the Systemd mistake and return to the modularity that made UNIX successful.
- Blackthorn 9y ago
  This attitude does not match history. If Unix really was about that philosophy, we would have never seen tools like emacs and perl gain any sort of popularity.
  - moe 9y ago
    UNIX philosophy[1] is not about popularity but about choice. We get to choose between Emacs/Vim, Perl/Python, Syslog-ng/RSyslog, ntpd/openntpd and so on. This has resulted in multiple mature implementations for every core system task. Yet instead of sticking with this code that has stood the test of time over decades, we threw it all out for a poorly written jack of all trades that gives root to usernames starting with a digit... [1] https://en.wikipedia.org/wiki/Unix_philosophy#Origin https://en.wikipedia.org/wiki/Unix_philosophy#Origin
- e40 9y ago
  Perhaps someone can explain why it was chosen as the replacement for SysV init, when all of the parent's comments/critiques of systemd were known in advance of it being pulled into major distros.
  - deleted 9y ago
    [deleted]
  - digi_owl 9y ago
    Bundling. systemd as a package is more than just init. It is init, inetd, session manager (logind), udev, dns client, dhcp client, cron, su, and the list keeps growing. Basic thing is that first of all Poettering to it a toehold at Fedora (he works at Red Hat, so surprise surprise). Then he offered Gnome the code for supporting logind on a silver platter. End result is that to offer Gnome as the desktop you either have to patch it, shim it (ask Canonical how well that worked out) or adopt systemd. Effectively what is happening is that Fedora is becoming the de-facto standard for Linux. In part because it is effectively the testing distro for Red Hat Enterprise Linux, and thus a large portion of userland devs (and a number of kernel devs) use it as their "dogfood".
viraptor 9y ago
Another vector: some services may create users and services on request. You don't have to trick the administrator to setup the account if the main purpose of some SaaS/PaaS is to take user's code and run it in local environment - possibly as a service, with the username controlled by the user.
hueving 9y ago
The attack vector this article doesn't mention is systems where systemd unit files are generated automatically. For example, on some shared clusters I used there was a capability to request a service run as your user. This was before systemd at the time so it would end up generating an /etc/init.d entry, but I imagine a modern equivalent might generate a unit file. So this article downplays the vulnerability a bit by claiming you have to trick a sysadmin when you could actually just use an automated service management system.
digi_owl 9y ago
> Fire in the hole! There's a new systemd bug that gets the haters aroused! Cute...
mamon 9y ago
Setting aside issue with user names starting with a digit: Why on earth would anyone use "root" as default, fall back value for user name? In case of unparseable/unrecognized value the sane thing to do would be to raise an error.
- falcolas 9y ago
  It's guaranteed to exist. I've run across systems where "nobody:nogroup" do not exist, so I am personally not aware of a better default user. That said, refusing to run the unit would be a better default behavior.
  - bigbugbag 9y ago
    And who guarantees it ? Is it really impossible to rename, edit, delete the root user ?
    - digi_owl 9y ago
      The name is just something easy to remember. But "root" will always be user 0 (zero). Gobolinux as a joke used to ship with user 0 named gobo rather than root, but i think they stopped doing so because it broke certain scripts etc that assumed root and 0 was equivalent.
- quickben 9y ago
  Easier to backdoor. Otherwise one would just deny the request for lack of access.
- code_duck 9y ago
  My impression is that the script is being run as root. It's going along, running everything as root... It encounters an attempt to run a command as a different user, and being unable to find a user matching that, says okay, whatever, I'll just run that as root too.
  - digi_owl 9y ago
falcolas 9y ago
Err, there are such things as user level systemd unit files[0]. I have no idea if this bug gets triggered by those as well, but it's a pretty big deal if it is. > There's a new systemd bug that gets the haters aroused! Oiy... I feel like I am walking into the middle of a Vim/Emacs flame war. Very unfortunate. [0] https://www.freedesktop.org/software/systemd/man/systemd.unit.html#id-1.7.5 https://www.freedesktop.org/software/systemd/man/systemd.uni... [EDIT] As noted downstream, the parsing error causes the 'User=' directive to just be ignored, so a user unit file will be run by the user. Still too many vectors of attack, sadly.
- joombaga 9y ago
  Yeah, Mattias is super defensive in this. It doesn't help your cause to downplay serious vulnerabilities in the software you're championing. Anyone acting like this is a point for upstart/sysvinit/whatever is obviously misguided; there's no need to preempt that misguidance.
- the_mitsuhiko 9y ago
  > I have no idea if this bug gets triggered by those as well Why should it? The bug is not that it runs as root but that it encounters a parsing error and uses the default. The default for root is root and the default for user A is user A.
  - falcolas 9y ago
    > Why should it? Thank you for the correct, if condescending, answer. It was unclear from the original bug, or this article, if it was falling back on a hardcoded 0 or the user used when the directive is not present. Since systemd's own behavior is inconsistent, I can't depend on that behavior to derive the reasonable answer. That inconsistency stems from the fact that a "valid" user name that doesn't exist triggers different behavior than an "invalid" user name; and the definition of "valid" is different between systemd and the rest of Linux.
peterkelly 9y ago
Another attack vector: An administrator deliberately creates a user starting with a 0, for example if they chose to name it after a system they are using (e.g. www.0xproject.com). They assume that the program is running as a user with limited privileges. Then, an exploit gets found in that program, and now instead of an attacker gaining user-level access, they now have root-level access. By far the most worrying part of the issue for me was that the developers said "oh it's not a bug" and just closed the issue, without properly thinking through the implications of the behaviour (such as the other attack vectors mentioned here). That's gross negligence.
- wolco 9y ago
  I agree finding a bug is part of the development lifecycle. Having the developer just close the bug and claim its not an issue is the worrisome part. When the next bug is found there is less reason to report it.
digi_owl 9y ago
Sadly it seems the "gamersgate" mob has latched onto systemd as another controversial topic to toy with...
- dijit 9y ago
  I'm having difficulty following the mental gymnastics required to follow your statement. Are you saying everyone you disagree with is "gamer gate"?
  - digi_owl 9y ago
    No, i am saying that at the height of gamersgate there seemed to be a mob of people that went around harassing (trolling if you will) the people involved simply because they found doing so amusing. And gamersgate lost media attention, my impression that a sizeable chunk of that mob has latched onto systemd as their target. The problem is that the people being harassed can't separate the harassers from the people voicing actual complaints, lumping them all into the trolls/haters bin. And frankly gamersgate was just the "peak" of a sorts, the root of it all lay further back. It is basically a mutated, nastier, form of the antics done under the "anonymous" moniker.
    - dijit 9y ago
      "Gamer gate" has absolutely nothing to do with legitimate criticisms of systemd. I am not a gamer, I have never trolled. I am a sysadmin in an 11,000+ person organisation and I have qualms with systemd. And frankly speaking, proponents of systemd usually fobbed us off by saying that we're dinosaurs. Or intentionally misrepresenting our arguments. Now we're being fobbed off as being some weird gaming industry crap? No.
      - digi_owl 9y ago
        Now you are misrepresenting what i am saying. I think there are legitimate complaints against systemd. but at the same time i also think there is harassment going on. From our side of the fence it is easy to tell the two apart. But from the systemd developer side, and apparently also the systemd proponent side, the two intermix. This akin to how hooligans join protest marches simply to start fights and riots, knowing it will be blamed on the legitimate protesters.
comstock 9y ago
The article says: "Should this be fixed? Yes, it's an obvious bug" The author of systemd says: "So, yeah, I don't think there's anything to fix in systemd here. I understand this is annoying, but still: the username is clearly not valid." And that's basically the problem. Not that the bug exists. But the systemd author doesn't recognize it as such, and refuses to fix it. This seems to be a recurring theme with systemd.
- kps 9y ago
  > the username is clearly not valid. It was, until systemd said it wasn't.
  - rnhmjoj 9y ago
    I understand the criticism towards systemd but let's not start making things up. From useradd (8) manual: "Usernames must start with a lower case letter or an underscore, followed by lower case letters, digits, underscores, or dashes. They can end with a dollar sign. In regular expression terms: [a-z_][a-z0-9_-]*[$]?"
    - dlgtho 9y ago
      Mine(Ubuntu) differs: It is usually recommended to only use usernames that begin with a lower case letter or an underscore, followed by lower case letters, digits, underscores, or dashes. They can end with a dollar sign. In regular expression terms: [a-z_][a-z0-9_-]*[$]? On Debian, the only constraints are that usernames must neither start with a dash ('-') nor plus ('+') nor tilde ('~') nor contain a colon (':'), a comma (','), or a whitespace (space: ' ', end of line: '\n', tabulation: '\t', etc.). Note that using a slash ('/') may break the default algorithm for the definition of the user's home directory.
    - kps 9y ago
      As dlgtho notes, your system's useradd(8) man page is not a description of all existing systems. Historically, the prohibitions were against ‘:’ (breaks passwd(5)), initial ‘-’ (mistaken for an option by login(1)), and upper case without lower case (makes getty(8) think you have an upper-case-only terminal). (Not much point in continuing this, since the post has dropped from front page to 7th in half an hour, and will never be seen again.)
baybal2 9y ago
Systemd's authors certainly deserve to be hounded relentlessly
- scrollaway 9y ago
  This is a seriously fucked up thing to say. Christ, do you even realize what you're saying? You're advocating for bullying people just because they were involved in writing a piece of software. Seek help.
  - deleted 9y ago
    [deleted]
  - baybal2 9y ago
    I see no reason not to hound out bad people from the developer community. It is a legitimate reaction to people whose offence of Linux development community goes far beyond writing bad software.
    - Ao7bei3s 9y ago
      No, personal attacks are never acceptable. Doubly so if you're an outsider who has done nothing for the project except attack the main developer. The legitimate way would be to take part in the development and convince based on technical reasons. If people disagree with you, consider that you might be wrong. If you think you're right anyway, fork it, and see if /other/ people agree with you. Chances are they won't. The people actually maintaining all the distros didn't all switch to systemd within a few years for no reason.
      - baybal2 9y ago
        >The people actually maintaining all the distros didn't all switch to systemd within a few years for no reason. They switched out of prospect having unmaintainable initscripts and having DEs being turned useless. RH/SystemD liaisoning with distro maintainers at around 2013 can be said to be trollish blackmail. Again, the point here is how apaling is the conduct of RH/SystemD core developers. SystemD could've been treated as a simple piece of bad software, if not for the group of people pushing it having such toxic personalities. You do not confront trolling with bugreports and patches.
throwanem 9y ago
Why will systemd start a unit it can't sensibly parse? If it thinks the user is invalid, shouldn't that be a fatal error?
- digi_owl 9y ago
  Sometimes it will, sometimes it won't. If you mangle the dependency chain in any way, you are likely to find yourself looking at the emergency console.
moomin 9y ago
May I propose Moomin's Law: Any statement about how hard a security issue is exploit is unlikely to be true unless made by someone who has exploited it.
bigbugbag 9y ago
I don't know the author and he does not provide context, so I don't really get what the fuss is about. Mentions haters, personal threats of violence but this looks like the usual: a bug in systemd due to an incorrect assumption by the developers, proposed solution: decide that there is no bug and systemd is correct, the use case is wrong. I experienced one first hand, a definition in fstab for a removable drive suddenly (after a systemd update and no warning) caused the computer to fail at boot time because the removable drive was not present. The fun part is that the emergency shell had a bug too that prevented itself from starting and looped to infinity instead. It was nice to have to drive 6h each way to deal with this systemd new "feature".
JdeBP 9y ago
The original bug report is already on Hacker News as https://news.ycombinator.com/item?id=14681377 https://news.ycombinator.com/item?id=14681377
Grue3 9y ago
https://github.com/systemd/systemd/issues/6237#issuecomment-311900864 https://github.com/systemd/systemd/issues/6237#issuecomment-... There are no words. How can someone so obviously incompetent be in charge of such an important open source project? Unless he's hired by some 3-letter agency to leave as many security holes in systemd as possible.

55 points by Mojah 9y ago

To me, this reflects as much on "many eyes make all bugs shallow" as on systemd. How many have used this feature without noticing that it has a serious bug? How many pairs of eyes have even passed over that particular piece of code without seeing what was wrong with it? More eyes only make bugs shallow when they're trained and diligent eyes.

udsloiwdaa 9y ago

/. is gonna have a field day.

digi_owl 9y ago
Nah, the bots will make sure the pro views get all the insightful votes...

moe 9y ago

Systemd is the disaster that happens when we ignore the lessons of UNIX. UNIX is all about small, composable tools. Do one job and do it well. One of these tools didn't stand up to the test of time (SysV init) and needed to be replaced. We could have chosen one of the mature candidates (upstart, runit, minit) or even built a great new one from scratch. Life would have been good. But instead we ended up with this trainwreck of a monolith that not only replaced init, but at the same time tried to reinvent almost every critical userspace daemon from Syslog to NTP. It predictably failed on every metric. Now it is time for the major Linux distributions to conclude this experiment, roll back the Systemd mistake and return to the modularity that made UNIX successful.

Blackthorn 9y ago
This attitude does not match history. If Unix really was about that philosophy, we would have never seen tools like emacs and perl gain any sort of popularity.
- moe 9y ago
  UNIX philosophy[1] is not about popularity but about choice. We get to choose between Emacs/Vim, Perl/Python, Syslog-ng/RSyslog, ntpd/openntpd and so on. This has resulted in multiple mature implementations for every core system task. Yet instead of sticking with this code that has stood the test of time over decades, we threw it all out for a poorly written jack of all trades that gives root to usernames starting with a digit... [1] https://en.wikipedia.org/wiki/Unix_philosophy#Origin https://en.wikipedia.org/wiki/Unix_philosophy#Origin
e40 9y ago
Perhaps someone can explain why it was chosen as the replacement for SysV init, when all of the parent's comments/critiques of systemd were known in advance of it being pulled into major distros.
- deleted 9y ago
  [deleted]
- digi_owl 9y ago
  Bundling. systemd as a package is more than just init. It is init, inetd, session manager (logind), udev, dns client, dhcp client, cron, su, and the list keeps growing. Basic thing is that first of all Poettering to it a toehold at Fedora (he works at Red Hat, so surprise surprise). Then he offered Gnome the code for supporting logind on a silver platter. End result is that to offer Gnome as the desktop you either have to patch it, shim it (ask Canonical how well that worked out) or adopt systemd. Effectively what is happening is that Fedora is becoming the de-facto standard for Linux. In part because it is effectively the testing distro for Red Hat Enterprise Linux, and thus a large portion of userland devs (and a number of kernel devs) use it as their "dogfood".

viraptor 9y ago

Another vector: some services may create users and services on request. You don't have to trick the administrator to setup the account if the main purpose of some SaaS/PaaS is to take user's code and run it in local environment - possibly as a service, with the username controlled by the user.

hueving 9y ago

The attack vector this article doesn't mention is systems where systemd unit files are generated automatically. For example, on some shared clusters I used there was a capability to request a service run as your user. This was before systemd at the time so it would end up generating an /etc/init.d entry, but I imagine a modern equivalent might generate a unit file. So this article downplays the vulnerability a bit by claiming you have to trick a sysadmin when you could actually just use an automated service management system.

digi_owl 9y ago

> Fire in the hole! There's a new systemd bug that gets the haters aroused! Cute...

mamon 9y ago

Setting aside issue with user names starting with a digit: Why on earth would anyone use "root" as default, fall back value for user name? In case of unparseable/unrecognized value the sane thing to do would be to raise an error.

falcolas 9y ago
It's guaranteed to exist. I've run across systems where "nobody:nogroup" do not exist, so I am personally not aware of a better default user. That said, refusing to run the unit would be a better default behavior.
- bigbugbag 9y ago
  And who guarantees it ? Is it really impossible to rename, edit, delete the root user ?
  - digi_owl 9y ago
    The name is just something easy to remember. But "root" will always be user 0 (zero). Gobolinux as a joke used to ship with user 0 named gobo rather than root, but i think they stopped doing so because it broke certain scripts etc that assumed root and 0 was equivalent.
quickben 9y ago
Easier to backdoor. Otherwise one would just deny the request for lack of access.
code_duck 9y ago
My impression is that the script is being run as root. It's going along, running everything as root... It encounters an attempt to run a command as a different user, and being unable to find a user matching that, says okay, whatever, I'll just run that as root too.
- digi_owl 9y ago

falcolas 9y ago

Err, there are such things as user level systemd unit files[0]. I have no idea if this bug gets triggered by those as well, but it's a pretty big deal if it is. > There's a new systemd bug that gets the haters aroused! Oiy... I feel like I am walking into the middle of a Vim/Emacs flame war. Very unfortunate. [0] https://www.freedesktop.org/software/systemd/man/systemd.unit.html#id-1.7.5 https://www.freedesktop.org/software/systemd/man/systemd.uni... [EDIT] As noted downstream, the parsing error causes the 'User=' directive to just be ignored, so a user unit file will be run by the user. Still too many vectors of attack, sadly.

joombaga 9y ago
Yeah, Mattias is super defensive in this. It doesn't help your cause to downplay serious vulnerabilities in the software you're championing. Anyone acting like this is a point for upstart/sysvinit/whatever is obviously misguided; there's no need to preempt that misguidance.
the_mitsuhiko 9y ago
> I have no idea if this bug gets triggered by those as well Why should it? The bug is not that it runs as root but that it encounters a parsing error and uses the default. The default for root is root and the default for user A is user A.
- falcolas 9y ago
  > Why should it? Thank you for the correct, if condescending, answer. It was unclear from the original bug, or this article, if it was falling back on a hardcoded 0 or the user used when the directive is not present. Since systemd's own behavior is inconsistent, I can't depend on that behavior to derive the reasonable answer. That inconsistency stems from the fact that a "valid" user name that doesn't exist triggers different behavior than an "invalid" user name; and the definition of "valid" is different between systemd and the rest of Linux.

peterkelly 9y ago

Another attack vector: An administrator deliberately creates a user starting with a 0, for example if they chose to name it after a system they are using (e.g. www.0xproject.com). They assume that the program is running as a user with limited privileges. Then, an exploit gets found in that program, and now instead of an attacker gaining user-level access, they now have root-level access. By far the most worrying part of the issue for me was that the developers said "oh it's not a bug" and just closed the issue, without properly thinking through the implications of the behaviour (such as the other attack vectors mentioned here). That's gross negligence.

wolco 9y ago
I agree finding a bug is part of the development lifecycle. Having the developer just close the bug and claim its not an issue is the worrisome part. When the next bug is found there is less reason to report it.

digi_owl 9y ago

Sadly it seems the "gamersgate" mob has latched onto systemd as another controversial topic to toy with...

dijit 9y ago
I'm having difficulty following the mental gymnastics required to follow your statement. Are you saying everyone you disagree with is "gamer gate"?
- digi_owl 9y ago
  No, i am saying that at the height of gamersgate there seemed to be a mob of people that went around harassing (trolling if you will) the people involved simply because they found doing so amusing. And gamersgate lost media attention, my impression that a sizeable chunk of that mob has latched onto systemd as their target. The problem is that the people being harassed can't separate the harassers from the people voicing actual complaints, lumping them all into the trolls/haters bin. And frankly gamersgate was just the "peak" of a sorts, the root of it all lay further back. It is basically a mutated, nastier, form of the antics done under the "anonymous" moniker.
  - dijit 9y ago
    "Gamer gate" has absolutely nothing to do with legitimate criticisms of systemd. I am not a gamer, I have never trolled. I am a sysadmin in an 11,000+ person organisation and I have qualms with systemd. And frankly speaking, proponents of systemd usually fobbed us off by saying that we're dinosaurs. Or intentionally misrepresenting our arguments. Now we're being fobbed off as being some weird gaming industry crap? No.
    - digi_owl 9y ago
      Now you are misrepresenting what i am saying. I think there are legitimate complaints against systemd. but at the same time i also think there is harassment going on. From our side of the fence it is easy to tell the two apart. But from the systemd developer side, and apparently also the systemd proponent side, the two intermix. This akin to how hooligans join protest marches simply to start fights and riots, knowing it will be blamed on the legitimate protesters.

comstock 9y ago

The article says: "Should this be fixed? Yes, it's an obvious bug" The author of systemd says: "So, yeah, I don't think there's anything to fix in systemd here. I understand this is annoying, but still: the username is clearly not valid." And that's basically the problem. Not that the bug exists. But the systemd author doesn't recognize it as such, and refuses to fix it. This seems to be a recurring theme with systemd.

kps 9y ago
> the username is clearly not valid. It was, until systemd said it wasn't.
- rnhmjoj 9y ago
  I understand the criticism towards systemd but let's not start making things up. From useradd (8) manual: "Usernames must start with a lower case letter or an underscore, followed by lower case letters, digits, underscores, or dashes. They can end with a dollar sign. In regular expression terms: [a-z_][a-z0-9_-]*[$]?"
  - dlgtho 9y ago
    Mine(Ubuntu) differs: It is usually recommended to only use usernames that begin with a lower case letter or an underscore, followed by lower case letters, digits, underscores, or dashes. They can end with a dollar sign. In regular expression terms: [a-z_][a-z0-9_-]*[$]? On Debian, the only constraints are that usernames must neither start with a dash ('-') nor plus ('+') nor tilde ('~') nor contain a colon (':'), a comma (','), or a whitespace (space: ' ', end of line: '\n', tabulation: '\t', etc.). Note that using a slash ('/') may break the default algorithm for the definition of the user's home directory.
  - kps 9y ago
    As dlgtho notes, your system's useradd(8) man page is not a description of all existing systems. Historically, the prohibitions were against ‘:’ (breaks passwd(5)), initial ‘-’ (mistaken for an option by login(1)), and upper case without lower case (makes getty(8) think you have an upper-case-only terminal). (Not much point in continuing this, since the post has dropped from front page to 7th in half an hour, and will never be seen again.)

baybal2 9y ago

Systemd's authors certainly deserve to be hounded relentlessly

scrollaway 9y ago
This is a seriously fucked up thing to say. Christ, do you even realize what you're saying? You're advocating for bullying people just because they were involved in writing a piece of software. Seek help.
- deleted 9y ago
  [deleted]
- baybal2 9y ago
  I see no reason not to hound out bad people from the developer community. It is a legitimate reaction to people whose offence of Linux development community goes far beyond writing bad software.
  - Ao7bei3s 9y ago
    No, personal attacks are never acceptable. Doubly so if you're an outsider who has done nothing for the project except attack the main developer. The legitimate way would be to take part in the development and convince based on technical reasons. If people disagree with you, consider that you might be wrong. If you think you're right anyway, fork it, and see if /other/ people agree with you. Chances are they won't. The people actually maintaining all the distros didn't all switch to systemd within a few years for no reason.
    - baybal2 9y ago
      >The people actually maintaining all the distros didn't all switch to systemd within a few years for no reason. They switched out of prospect having unmaintainable initscripts and having DEs being turned useless. RH/SystemD liaisoning with distro maintainers at around 2013 can be said to be trollish blackmail. Again, the point here is how apaling is the conduct of RH/SystemD core developers. SystemD could've been treated as a simple piece of bad software, if not for the group of people pushing it having such toxic personalities. You do not confront trolling with bugreports and patches.

throwanem 9y ago

Why will systemd start a unit it can't sensibly parse? If it thinks the user is invalid, shouldn't that be a fatal error?

digi_owl 9y ago
Sometimes it will, sometimes it won't. If you mangle the dependency chain in any way, you are likely to find yourself looking at the emergency console.

moomin 9y ago

May I propose Moomin's Law: Any statement about how hard a security issue is exploit is unlikely to be true unless made by someone who has exploited it.

bigbugbag 9y ago

I don't know the author and he does not provide context, so I don't really get what the fuss is about. Mentions haters, personal threats of violence but this looks like the usual: a bug in systemd due to an incorrect assumption by the developers, proposed solution: decide that there is no bug and systemd is correct, the use case is wrong. I experienced one first hand, a definition in fstab for a removable drive suddenly (after a systemd update and no warning) caused the computer to fail at boot time because the removable drive was not present. The fun part is that the emergency shell had a bug too that prevented itself from starting and looped to infinity instead. It was nice to have to drive 6h each way to deal with this systemd new "feature".

JdeBP 9y ago

The original bug report is already on Hacker News as https://news.ycombinator.com/item?id=14681377 https://news.ycombinator.com/item?id=14681377

Grue3 9y ago

https://github.com/systemd/systemd/issues/6237#issuecomment-311900864 https://github.com/systemd/systemd/issues/6237#issuecomment-... There are no words. How can someone so obviously incompetent be in charge of such an important open source project? Unless he's hired by some 3-letter agency to leave as many security holes in systemd as possible.