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Linux systemd Affected by Memory Corruption Vulnerabilities, No Patches Yet (bleepingcomputer.com)
Major Linux distributions are vulnerable to three bugs in systemd, a Linux initialization system and service manager in widespread use, California-based security company Qualys said late yesterday. From a report: The bugs exist in 'journald' service, tasked with collecting and storing log data, and they can be exploited to obtain root privileges on the target machine or to leak information. No patches exist at the moment. Discovered by researchers at Qualys, the flaws are two memory corruption vulnerabilities (stack buffer overflow - CVE-2018-16864, and allocation of memory without limits - CVE-2018-16865) and one out-of-bounds error (CVE-2018-16866). They were able to obtain local root shell on both x86 and x64 machines by exploiting CVE-2018-16865 and CVE-2018-16866. The exploit worked faster on the x86 platform, achieving its purpose in ten minutes; on x64, though, the exploit took 70 minutes to complete. Qualys is planning on publishing the proof-of-concept exploit code in the near future, but they did provide details on how they were able to take advantage of the flaws.
Giant bloated executable where trim purpose built utilities and text should be used.
Looking at the code, all three of these bugs are inexcusable. The systemd devs really are incompetent.
In case you're interested to know the breakdown...
Politics; n. : A religion whereby man is god.
for me... I switched to Devuan a few months ago.
Yes, I know there are plenty of bugs and vulnerabilities to go around, but based on the frustrations that systemd caused me, I think I am afforded a bit of schadenfreude.
My beliefs do not require that you agree with them.
Shitty windows-ini-style Unit files, binary logs, 12 different subsystems gobbled up and "integrated" ... I mean did this kind of shit surprise someone? Really? After years of supporting Systemd and solving it's problems for others I can say with limited authority that, yes, it really is garbage. I know there were a few people who thought systemd was just "progress", but no it's a schism, a coup, a shitty revolution that left everyone worse than when they started. Linus and friends are too old and retarded now apparently to lose face and be critical of it because they stood by and shrugged while the Potterites and Fedora assholes ruined Linux. I mean BSD was always better, don't get me wrong. So, it's not as big a loss as some would frame it to be. However, it used to be fun, useful, and relatively untainted by anything this heinous but a few unenlightened windows folks came along and created this svchost.exe ripoff (systemd) for the purposes of enhancing GNOME and now you get this smelly mess that is now Linux. Ah well, it was (sorta) fun while it lasted. Back to my BSD boxes.
It's less about resisting change and more about resisting stupid.
The problem with systemd is that its design is wholly antithetical to the Unix philosophy. It is nothing less than a tragedy for Linux that something like it has become so tightly integrated into as many distros as it has.
File under 'M' for 'Manic ranting'
Probably a good chunk.
That said, init and upstart solved problems in a fairly small domain: starting daemons in dependency order. SMF, launchd, and a few others did the same thing. They sucked to learn, but they gave us parallel startup, services that could start in response to events (logins, socket connects, etc.) and that was worth some relearning.
Things that systemd has embraced into its scope that SMD and launchd did not include:
Thanks to RedHat's backing, the systemd developers have a bully pulpit to force policy on Linux users everywhere. Like when nohup stopped working by default. The usual rationale from Poettering and company are that things are "broken" or "nobody needs that."
Right now, on my Debian box, in ~root/ is a script called thanks-systemd.sh. It mostly boils down to: cd /dev ; for i in dm-? ; do ln -s ../$i mapper/$(cat /sys/devices/virtual/block/${i}/dm/name); done
Because for about two weeks my system stopped autobooting due to some churn between LVM2 and systemd. LVM2's worked nigh-flawlessly for 20 years, and its semantics haven't changed.
It's one thing to change a clunky misfeature (init scripts) in some jarring way to make them better. It's quite another to take over most aspects of systems management, do them differently "just because," and break random things because of scope creep.
Pining for the days when The Glorious MEEPT!!! graced SlapDash with his wisdom.
Yet I can't help wondering how much of it is really just people who resist change because they don't want to learn something new. The init/upstart process was easy enough to understand but clinky and as full of problems as systemd really. Except, of course of the most common use cases where it had been worked out.
Gonna call citation needed on that, especially if you're combining them as "init/upstart".
upstart, when primarily running as a traditional SysV init (meaning handle initial setup procedureally, then execute an rc script which executes a series of rc#.d/ scripts, which is how upstart was used in RHEL6, for example, was neither "clinky" nor "as full of problems as systemd".
A primary reason so many people have problems with systemd is that it intermingles the complexity along its entire axis of execution instead of isolating it in a discrete manner. Any time you have event-based management you have the potential for intermittent problems, race condition security issues, memory bugs, etc.
In previous init systems, persistent management or event mechanisms hung *OFF* the init path and only affected their own children or the services under their control if something went wrong. (This goes for all service managers: inet, xinetd, supervise, whatever.) Meanwhile, the init path is controlled by one-time scripts and as minimal an event mechanism in PID1 as possible.
Now, all that complexity happens as PID1, or communicates back to PID1, or relies on IPC between the two that is not particularly tight and isolated. Waaaaay more potential for chaos results here, which is why these types of holes are more and more likely to occur.
Hire a Linux system administrator, systems engineer,
"The init/upstart process was easy enough to understand but clinky and as full of problems as systemd really."
No, it really wasn't. You are confusing user error with the actual utilities which were rock solid. There was some functionality missing but alternatives existed, they largely weren't widely adopted because that functionality just didn't offer enough benefit to be worth it.
The problem with systemd is that it was a solution that was built and broke all *nix design philosophy. Every layer of complexity added to a framework adds an order of magnitude of probability for error and trades flexibility for tight integration. If a bug does come up it will be fixed almost immediately with small and efficient utilities because you aren't debugging a complex behemoth you are debugging a tiny and simple application.
It really does just suck. It's not haters, it's not bias, it's not politics. It's also not only people resisting change, Systemd is just flat out technically inferior. Bad choices were made and the chickens definitely are coming home to roost. I get a *lot* of calls from frustrated/confused sysadmins who run into issue after issue with systemd. From subtle problems from malformed unit files to clear-as-mud dependency graph issues between units. Yes, they are fixable most of the time but systemd just throws obstacle after obstacle into your path. Want to know why something didn't work? Well, there's journald hording your logs as binary. Hope you have the magic decoder when your system crashes and journalctl pukes. I dug into systemd deeply because I support Linux and other systems professionally. I've studied a lot of the code to run down bugs or issues. I learned it quite well and it seems obvious that I know it's internals better than it's cheerleaders do. It shouldn't be this controversial. The only reason it is stems from the leadership folks not wanting to lose face and admit they made a serious mistake. Systemd sucks on it's own. It doesn't need fixing, it needs replacing. It's bad design that violates the "do one thing and do it well". It does a zillion things: all poorly.
Slackware ships with a simple, effective BSD-style init populated by simple and readable shell scripts. [....] Install Slackware, and many sysadmin's worries will go away.
You are missing the forest for the trees. What you really want isnt a "BSD-style init", what you really want is BSD.
Linux isnt unix, so dont expect it to maintain the unix philosophy. BSD is unix.
Fun fact: Been true forever
"His name was James Damore."
the one thing I learned at the place I work is that people and businesses are not rewarded for perfect code -- trouble-free code results in the project being thought of as small and not valuable -- if you want money, you need to build complex and buggy code - systemd supporters are no dummies and know what it takes to earn more money
Even simpler than a systemd declaration is saying "Alexa, start Apache".
That doesn't mean that Alexa's AI code is simpler than a 20-line bash script. You're comparing the *input* to the systemd code, a config file, vs the actual code that does things in SysVinit.
In sys V, the shell script starts the daemon, it *is* the code. If anything is wrong or you want to change anything, you can look through the shell script and change things. In systemd, the declaration is handed to a binary that does who-knows-what.
I was a RedHat user back on v5.1. I tried to upgrade my system, and it was awfully painful. But I stuck with RedHat. Then I upgraded again. And again. Every time it got a little less painful, but it still sucked. Then I decided to try out another distro. Mandrake. It was nice, and I liked KDE! I upgraded a couple of times, and it wasn't too bad. So change was good. After a few more upgrades, it still wasn't that smooth. I decided to try out Ubuntu, and I really liked it. Since I was liking KDE I switched to Kubuntu. Change was good! I upgraded a couple of times - near flawless! Change was great! Then KDE started to really annoy me - too much flash, and eventually a bug cropped up that caused me all kinds of headaches. So I switched to Xubuntu. XFCE was great, and change was good! I upgraded that system several times, and it was very smooth. After 7 upgrades, things were getting less stable. Since i was going to reinstall anyway, i looked at other distros.... ah, Linux Mint. Polished, but with XFCE not overly so. I had found my distro, change was great! The method of upgrading was to reinstall cleanly, so I made sure to set up my new system so that was minimally painful. Then I was able to upgrade in place - painlessly! All was right.
Then after one upgrade, I noticed that my machine started having various issues. I couldn't shutdown cleanly. I would take minutes to shutdown, where it used to take seconds. I thought it was hardware at first, but it wasn't. It was systemd. I hadn't noticed before upgrading that they were switching to systemd. I had begun to trust Mint so much that I just thought it would be smooth. I learned more and more about systemd, and tried to fix the issue. No deal. So I gritted my teeth and dealt with it. Change can be bad. Eventually I got a different computer, and then I had complete confirmation that my issues weren't hardware related because they persisted. It was time to find a new distro.
It wasn't an easy search, because by this time systemd had kind of taken over. Mint only went to it because it's a downstream of Ubuntu. Clem (maintainer of Mint) confirmed this to me, that it wasn't his choice at all and it was just the easiest route to take.
I looked at the BSDs, Arch, Slack, and a few others. But because I was familiar with and really liked the apt package manager, I chose Devuan. It was not only a great distro, but I know that it is specifically focused on NOT implementing systemd. It was a simple install and upgrade, and my system is fast as ever and shuts down within seconds again. So again... change is great!
My beliefs do not require that you agree with them.