BSD Now

Unix virtual memory when you have no swap space, Dsynth details on Dragonfly, Instant Workstation on FreeBSD, new servers new tech, Experimenting with streaming setups on NetBSD, NetBSD’s progress towards Steam support thanks to GSoC, and more.

Recently, Artem S. Tashkinov wrote on the Linux kernel mailing list about a Linux problem under memory pressure (via, and threaded here). The specific reproduction instructions involved having low RAM, turning off swap space, and then putting the system under load, and when that happened (emphasis mine):

Once you hit a situation when opening a new tab requires more RAM than is currently available, the system will stall hard. You will barely be able to move the mouse pointer. Your disk LED will be flashing incessantly (I'm not entirely sure why). [...]

I'm afraid I have bad news for the people snickering at Linux here; if you're running without swap space, you can probably get any Unix to behave this way under memory pressure. If you can't on your particular Unix, I'd actually say that your Unix is probably not letting you get full use out of your RAM.

To simplify a bit, we can divide pages of user memory up into anonymous pages and file-backed pages. File-backed pages are what they sound like; they come from some specific file on the filesystem that they can be written out to (if they're dirty) or read back in from. Anonymous pages are not backed by a file, so the only place they can be written out to and read back in from is swap space. Anonymous pages mostly come from dynamic memory allocations and from modifying the program's global variables and data; file backed pages come mostly from mapping files into memory with mmap() and also, crucially, from the code and read-only data of the program.

First, history: DragonFly has had binaries of dports available for download for quite some time. These were originally built using poudriere, and then using the synth tool put together by John Marino. Synth worked both to build all software in dports, and as a way to test DragonFly’s SMP capability under extreme load.

Matthew Dillon is working on a new version, called dsynth. It is available now but not yet part of the build. He’s been working quickly on it and there’s plenty more commits than what I have linked here. It’s already led to finding more high-load fixes.

DSynth is basically synth written in C, from scratch. It is designed to give us a bulk builder in base and be friendly to porting and jails down the line (for now its uses chroot's).

The original synth was written by John R. Marino and its basic flow was used in writing this program, but as it was written in ada no code was directly copied.

Some considerable time ago I wrote up instructions on how to set up a FreeBSD machine with the latest KDE Plasma Desktop. Those instructions, while fairly short (set up X, install the KDE meta-port, .. and that’s it) are a bit fiddly.

So – prompted slightly by a Twitter exchange recently – I’ve started a mini-sub-project to script the installation of a desktop environment and the bits needed to support it. To give it at least a modicum of UI, dialog(1) is used to ask for an environment to install and a display manager.

The tricky bits – pointed out to me after I started – are hardware support, although a best-effort is better than having nothing, I think.

In any case, in a VBox host it’s now down to running a single script and picking Plasma and SDDM to get a usable system for me. Other combinations have not been tested, nor has system-hardware-setup. I’ll probably maintain it for a while and if I have time and energy it’ll be tried with nVidia (those work quite well on FreeBSD) and AMD (not so much, in my experience) graphics cards when I shuffle some machines around.

Following up on an earlier post, the new servers for DragonFly are in place. The old 40-core machine used for bulk build, monster, is being retired. The power efficiency of the new machines is startling. Incidentally, this is where donations go – infrastructure.

We have three new servers in the colo now that will be taking most/all bulk package building duties from monster and the two blades (muscles and pkgbox64) that previously did the work. Monster will be retired. The new servers are a dual-socket Xeon (sting) and two 3900X based systems (thor and loki) which all together burn only around half the wattage that monster burned (500W vs 1000W) and 3 times the performance. That's at least a 6:1 improvement in performance efficiency.

With SSD prices down significantly the new machines have all-SSDs. These new machines allow us to build dports binary packages for release, master, and staged at the same time and reduces the full-on bulk build times for getting all three done down from 2 weeks to 2 days. It will allow us to more promptly synchronize updates to ports with dports and get binary packages up sooner.

Monster, our venerable 48-core quad-socket opteron is being retired. This was a wonderful dev machine for working on DragonFly's SMP algorithms over the last 6+ years precisely because its inter-core and inter-socket latencies were quite high. If a SMP algorithm wasn't spot-on, you could feel it. Over the years DragonFly's performance on monster in doing things like bulk builds increased radically as the SMP algorithms got better and the cores became more and more localized. This kept monster relevant far longer than I thought it would be.

But we are at a point now where improvements in efficiency are just too good to ignore. Monster's quad-socket opteron (4 x 12 core 6168's) pulls 1000W under full load while a single Ryzen 3900X (12 core / 24 thread) in a server configuration pulls only 150W, and is slightly faster on the same workload to boot.

I would like to thank everyone's generous donations over the last few years! We burned a few thousand on the new machines (as well as the major SSD upgrades we did to the blades) and made very good use of the money, particularly this year as prices for all major components (RAM, SSDs, CPUs, Mobos, etc) have dropped significantly.

Ever since OBS was successfully ported to NetBSD, I’ve been trying it out, seeing what works and what doesn’t. I’ve only just gotten started, and there’ll definitely be a lot of tweaking going forward.

Capturing a specific application’s windows seems to work okay. Capturing an entire display works, too. I actually haven’t tried streaming to Twitch or YouTube yet, but in a previous experiment a few weeks ago, I was able to run a FFmpeg command line and that could stream to Twitch mostly OK.

My laptop combined with my external monitor allows me to have a dual-monitor setup wherein the smaller laptop screen can be my “broadcasting station” while the bigger screen is where all the action takes place. I can make OBS visible on all Xfce workspaces, but keep it tucked away on that display only. Altogether, the setup should let me use the big screen for the fun stuff but I can still monitor everything in the small screen.

Ultimately the goal is to get Valve's Steam client running on NetBSD using their Linux compatibility layer while the focus the past few months with Google Summer of Code 2019 were supporting the necessary DRM ioctls for allowing Linux software running on NetBSD to be able to tap accelerated graphics support.

Student developer Surya P spent the summer working on compat_netbsd32 DRM interfaces to allow Direct Rendering Manager using applications running under their Linux compatibility layer.

These interfaces have been tested and working as well as updating the "suse131" packages in NetBSD to make use of those interfaces. So the necessary interfaces are now in place for Linux software running on NetBSD to be able to use accelerated graphics though Steam itself isn't yet running on NetBSD with this layer.

Those curious about this DRM ioctl GSoC project can learn more from the NetBSD blog. NetBSD has also been seeing work this summer on Wayland support and better Wine support to ultimately make this BSD a better desktop operating system and potentially a comparable gaming platform to Linux.

OpenBSD on 7th gen Thinkpad X1 Carbon, how to install FreeBSD on a MacBook, Kernel portion of in-kernel TLS (KTLS), Boot Environments on DragonflyBSD, Project Trident Updates, vBSDcon schedule, and more.

Another year, another ThinkPad X1 Carbon, this time with a Dolby Atmos sound system and a smaller battery.

FreeBSD with some additional setup can be installed on a MacBook 1,1 or 2,1. This article covers how to do so with FreeBSD 10-12.

FreeBSD can be installed as the only OS on your MacBook if desired. What you should have is:

One of the projects I have been working on for the past several months in conjunction with several other folks is upstreaming work from Netflix to handle some aspects of Transport Layer Security (TLS) in the kernel. In particular, this lets a web server use sendfile() to send static content on HTTPS connections. There is a lot more detail in the review itself, so I will spare pasting a big wall of text here. However, I have posted the patch to add the kernel-side of KTLS for review at the URL below. KTLS also requires other patches to OpenSSL and nginx, but this review is only for the kernel bits. Patches and reviews for the other bits will follow later.

This is a tool inspired by the beadm utility for FreeBSD/Illumos systems that creates and manages ZFS boot environments. This utility in contrast is written from the ground up in C, this should provide better performance, integration, and extensibility than the POSIX sh and awk script it was inspired by. During the time this project has been worked on, beadm has been superseded by bectl on FreeBSD. After hammering out some of the outstanding internal logic issues, I might look at providing a similar interface to the command as bectl.

This is a general package update to the CURRENT release repository based upon TrueOS 19.08.

This is the third general package update to the STABLE release repository based upon TrueOS 12-Stable.

The UNIX Philosophy in 2019, why use package managers, touchpad interrupted, Porting wine to amd64 on NetBSD second evaluation report, Enhancing Syzkaller Support for NetBSD, all about the Pinebook Pro, killing a process and all of its descendants, fast software the best software, and more.

Today, Linux and open source rules the world, and the UNIX philosophy is widely considered compulsory. Organizations are striving to build small, focused applications that work collaboratively in a cloud and microservices environment. We rely on the network, as well as HTTP (text) APIs for storing and referencing data. Moreover, nearly all configuration is stored and communicated using text (e.g. YAML, JSON or XML). And while the UNIX philosophy has changed dramatically over the past 5 decades, it hasn’t strayed too far from Ken Thompson’s original definition in 1973:

Valuable research is often hindered or outright prevented by the inability to install software. This need not be the case.

Since I began supporting research computing in 1999, I’ve frequently seen researchers struggle for days or weeks trying to install a single open source application. In most cases, they ultimately failed.

In many cases, they could have easily installed the software in seconds with one simple command, using a package manager such as Debian packages, FreeBSD ports, MacPorts, or Pkgsrc, just to name a few.

Developer websites often contain poorly written instructions for doing “caveman installs”; manually downloading, unpacking, patching, and building the software. The same laborious process must often be followed for other software packages on which it depends, which can sometimes number in the dozens. Many researchers are simply unaware that there are easier ways to install the software they need. Caveman installs are a colossal waste of man-hours. If 1000 people around the globe spend an average of 20 hours each trying to install the same program that could have been installed with a package manager (this is not uncommon), then 20,000 man-hours have been lost that could have gone toward science. How many important discoveries are delayed by this?

The elite research institutions have ample funding and dozens of IT staff dedicated to research computing. They can churn out publications even if their operation is inefficient. Most institutions, however, have few or no IT staff dedicated to research, and cannot afford to squander precious man-hours on temporary, one-off software installs. The wise approach for those of us in that situation is to collaborate on making software deployment easier for everyone. If we do so, then even the smallest research groups can leverage that work to be more productive and make more frequent contributions to science.

Fortunately, the vast majority of open source software installs can be made trivial for anyone to do for themselves. Modern package managers perform all the same steps as a caveman install, but automatically. Package managers also install dependencies for us automatically.

For two years I've been driving myself crazy trying to figure out the source of a driver problem on OpenBSD: interrupts never arrived for certain touchpad devices. A couple weeks ago, I put out a public plea asking for help in case any non-OpenBSD developers recognized the problem, but while debugging an unrelated issue over the weekend, I finally solved it.

It's been a long journey and it's a technical tale, but here it is.

Presently, Wine on amd64 is in test phase. It seems to work fine with caveats like LD_LIBRARY_PATH which has to be set as 32-bit Xorg libs don't have ${PREFIX}/emul/netbsd32/lib in its rpath section. The latter is due to us extracting 32-bit libs from tarballs in lieu of building 32-bit Xorg on amd64. As previously stated, pkgsrc doesn't search for pkgconfig files in ${PREFIX}/emul/netbsd32/lib which might have inadvertent effects that I am unaware of as of now. I shall be working on these issues during the final coding period. I would like to thank @leot, @maya and @christos for saving me from shooting myself in the foot many a time. I, admittedly, have had times when multiple approaches, which all seemed right at that time, perplexed me. I believe those are times when having a mentor counts, and I have been lucky enough to have really good ones. Once again, thanks to Google for this wonderful opportunity.

As a part of Google Summer of Code’19, I am working on improving the support for Syzkaller kernel fuzzer. Syzkaller is an unsupervised coverage-guided kernel fuzzer, that supports a variety of operating systems including NetBSD. This report details the work done during the second coding period.

You can also take a look at the first report to learn more about the initial support that we added. : https://blog.netbsd.org/tnf/entry/enhancing_syzkaller_support_for_netbsd

"So I said I won’t be talking about the BSDs, but I feel like I should at the very least give you a general overview of the RK3399 *BSD functionality. I’ll make it quick. I’ve spoken to *BSD devs whom worked on the RockPro64 and from what I’ve gathered (despite the different *BSDs having varying degree of support for the RK3399 SOC) many of the core features are already supported, which bodes well for *BSD on the Pro. That said, some of the things you’d require on a functional laptop – such as the LCD (using eDP) for instance – will not work on the Pinebook Pro using *BSD as of today. So clearly a degree of work is yet needed for a BSD to run on the device. However, keep in mind that *BSD developers will be receiving their units soon and by the time you receive yours some basic functionality may be available."

Killing processes in a Unix-like system can be trickier than expected. Last week I was debugging an odd issue related to job stopping on Semaphore. More specifically, an issue related to the killing of a running process in a job. Here are the highlights of what I learned:

Unix-like operating systems have sophisticated process relationships. Parent-child, process groups, sessions, and session leaders. However, the details are not uniform across operating systems like Linux and macOS. POSIX compliant operating systems support sending signals to process groups with a negative PID number.

Sending signals to all processes in a session is not trivial with syscalls.

Child processes started with exec inherit their parent signal configuration. If the parent process is ignoring the SIGHUP signal, for example, this configuration is propagated to the children.

The answer to the “What happens with orphaned process groups” question is not trivial.

I love fast software. That is, software speedy both in function and interface. Software with minimal to no lag between wanting to activate or manipulate something and the thing happening. Lightness.

Software that’s speedy usually means it’s focused. Like a good tool, it often means that it’s simple, but that’s not necessarily true. Speed in software is probably the most valuable, least valued asset. To me, speedy software is the difference between an application smoothly integrating into your life, and one called upon with great reluctance. Fastness in software is like great margins in a book — makes you smile without necessarily knowing why.

But why is slow bad? Fast software is not always good software, but slow software is rarely able to rise to greatness. Fast software gives the user a chance to “meld” with its toolset. That is, not break flow. When the nerds upon Nerd Hill fight to the death over Vi and Emacs, it’s partly because they have such a strong affinity for the flow of the application and its meldiness. They have invested. The Tool Is Good, so they feel. Not breaking flow is an axiom of great tools.

A typewriter is an excellent tool because, even though it’s slow in a relative sense, every aspect of the machine itself operates as quickly as the user can move. It is focused. There are no delays when making a new line or slamming a key into the paper. Yes, you have to put a new sheet of paper into the machine at the end of a page, but that action becomes part of the flow of using the machine, and the accumulation of paper a visual indication of work completed. It is not wasted work. There are no fundamental mechanical delays in using the machine. The best software inches ever closer to the physical directness of something like a typewriter. (The machine may break down, of course, ribbons need to be changed — but this is maintenance and separate from the use of the tool. I’d be delighted to “maintain” Photoshop if it would lighten it up.)

NetBSD 9.0 release process has started, xargs, a tale of two spellcheckers, Adapting TriforceAFL for NetBSD, Exploiting a no-name freebsd kernel vulnerability, and more.

If you have been following source-changes, you may have noticed the creation of the netbsd-9 branch! It has some really exciting items that we worked on:

We try to test NetBSD as best as we can, but your testing can help NetBSD 9.0 a great release. Please test it and let us know of any bugs you find.

xargs is probably one of the more difficult to understand of the unix command arsenal and of course that just means it’s one of the most useful too.

This is a transcript of the talk I gave at pkgsrcCon 2019 in Cambridge, UK. It is about spellcheckers, but there are much more general software engineering lessons that we can learn from this case study.

I have been working on adapting TriforceAFL for NetBSD kernel syscall fuzzing. This blog post summarizes the work done until the second evaluation.

GlocalMe G3 Mobile Travel HotSpot and Powerbank

Huawei E5770s-320 4G LTE 150 Mbps Mobile WiFi Pro

OPNsense 19.7.1 is out, ZFS on Linux still has annoying issues with ARC size, Hammer2 is now default, NetBSD audio – an application perspective, new FreeNAS Mini, and more.

We do not wish to keep you from enjoying your summer time, but this

Full patch notes:

Stay safe and hydrated, Your OPNsense team

One of the frustrating things about operating ZFS on Linux is that the ARC size is critical but ZFS's auto-tuning of it is opaque and apparently prone to malfunctions, where your ARC will mysteriously shrink drastically and then stick there.

Linux's regular filesystem disk cache is very predictable; if you do disk IO, the cache will relentlessly grow to use all of your free memory. This sometimes disconcerts people when free reports that there's very little memory actually free, but at least you're getting value from your RAM. This is so reliable and regular that we generally don't think about 'is my system going to use all of my RAM as a disk cache', because the answer is always 'yes'. (The general filesystem cache is also called the page cache.)

This is unfortunately not the case with the ZFS ARC in ZFS on Linux (and it wasn't necessarily the case even on Solaris). ZFS has both a current size and a 'target size' for the ARC (called 'c' in ZFS statistics). When your system boots this target size starts out as the maximum allowed size for the ARC, but various events afterward can cause it to be reduced (which obviously limits the size of your ARC, since that's its purpose). In practice, this reduction in the target size is both pretty sticky and rather mysterious (as ZFS on Linux doesn't currently expose enough statistics to tell why your ARC target size shrunk in any particular case).

The net effect is that the ZFS ARC is not infrequently quite shy and hesitant about using memory, in stark contrast to Linux's normal filesystem cache. The default maximum ARC size starts out as only half of your RAM (unlike the regular filesystem cache, which will use all of it), and then it shrinks from there, sometimes very significantly, and once shrunk it only recovers slowly (if at all).

NetBSD audio – an application perspective ... or, "doing it natively, because we can"

Two new FreeNAS Mini systems join the very popular FreeNAS Mini and Mini XL:

FreeNAS Mini XL+: This powerful 10 Bay platform (8x 3.5” and 1x 2.5” hot-swap, 1x 2.5” internal) includes the latest, compact server technology and provides dual 10GbE ports, 8 CPU cores and 32 GB RAM for high performance workgroups. The Mini XL+ scales beyond 100TB and is ideal for very demanding applications, including hosting virtual machines and multimedia editing. Starting at $1499, the Mini XL+ configured with cache SSD and 80 TB capacity is $4299, and consumes about 100 Watts.

FreeNAS Mini E: This cost-effective 4 Bay platform provides the resources required for SOHO use with quad GbE ports and 8 GB of RAM. The Mini E is ideal for file sharing, streaming and transcoding video at 1080p. Starting at $749, the Mini E configured with 8 TB capacity is $999, and consumes about 36 Watts.

DragonFlyBSD Project Update - colo upgrade, future trends, resuming ZFS send, realtime bandwidth terminal graph visualization, fixing telnet fixes, a chapter from the FBI’s history with OpenBSD and an OpenSSH vuln, and more.

For the last week I've been testing out a replacement for Monster, our 48-core opteron server. The project will be removing Monster from the colo in a week or two and replacing it with three machines which together will use half the power that Monster did alone.

The goal is to clear out a little power budget in the colo and to really beef-up our package-building capabilities to reduce the turn-around time needed to test ports syncs and updates to the binary package system.

Currently we use two blades to do most of the building, plus monster sometimes. The blades take almost a week (120 hours+) to do a full synth run and monster takes around 27.5 hours. But we need to do three bulk builds more or less at the same time... one for the release branch, one for the development branch, and one for staging updates. It just takes too long and its been gnawing at me for a little while.

Well, Zen 2 to the rescue! These new CPUs can take ECC, there's actually an IPMI mobo available, and they are fast as hell and cheap for what we get.

The new machines will be two 3900X based servers, plus a dual-xeon system that I already had at home. The 3900X's can each do a full synth run in 24.5 hours and the Xeon can do it in around 31 hours. Monster will be retired. And the crazy thing about this? Monster burns 1000W going full bore. Each of the 3900X servers burns 160W and the Xeon burns 200W. In otherwords, we are replacing 1000W with only 520W and getting roughly 6x the performance efficiency in the upgrade. This tell you just how much more power-efficient machines have become in the last 9 years or so. > This upgrade will allow us to do full builds for both release and dev in roughly one day instead of seven days, and do it without interfering with staging work that might be happening at the same time.

Future trends - DragonFlyBSD has reached a bit of a cross-roads. With most of the SMP work now essentially complete across the entire system the main project focus is now on supplying reliable binary ports for release and developer branches, DRM (GPU) support and other UI elements to keep DragonFlyBSD relevant on workstations, and continuing Filesystem work on HAMMER2 to get multi-device and clustering going.

One of the amazing functionalities of ZFS is the possibility of sending a whole dataset from one place to another. This mechanism is amazing to create backups of your ZFS based machines. Although, there were some issues with this functionality for a long time when a user sent a big chunk of data. What if you would do that over the network and your connection has disappeared? What if your machine was rebooted as you are sending a snapshot?

For a very long time, you didn't have any options - you had to send a snapshot from the beginning. Now, this limitation was already bad enough. However, another downside of this approach was that all the data which you already send was thrown away. Therefore, ZFS had to go over all this data and remove them from the dataset. Imagine the terabytes of data which you sent via the network was thrown away because as you were sending the last few bytes, the network went off.

In this short post, I don't want to go over the whole ZFS snapshot infrastructure (if you think that such a post would be useful, please leave a comment). Now, to get back to the point, this infrastructure is used to clone the datasets. Some time ago a new feature called “Resuming ZFS send” was introduced. That means that if there was some problem with transmitting the dataset from one point to another you could resume it or throw them away. But the point is, that yes, you finally have a choice.

If for some reasons you want to visualize your bandwidth traffic on an interface (in or out) in a terminal with a nice graph, here is a small script to do so, involving ttyplot, a nice software making graphics in a terminal.

The following will works on OpenBSD. You can install ttyplot by pkg_add ttyplot as root, ttyplot package appeared since OpenBSD 6.5.

There’s a FreeBSD commit to telnet. fix a couple of snprintf() buffer overflows. It’s received a bit of attention for various reasons, telnet in 2019?, etc. I thought I’d take a look. Here’s a few random observations.

Earlier this year I FOIAed the FBI for details on allegations of backdoor installed in the IPSEC stack in 2010, originally discussed by OpenBSD devs (https://marc.info/?l=openbsd-tech&m=129236621626462 …) Today, I got an interesting but unexpected responsive record:

Replacing a (silently) failing disk in a ZFS pool, OPNsense 19.7 RC1 released, implementing DRM ioctl support for NetBSD, High quality/low latency VOIP server with umurmur/Mumble on OpenBSD, the PDP-7 where Unix began, LLDB watchpoints, and more.

Maybe I can’t read, but I have the feeling that official documentations explain every single corner case for a given tool, except the one you will actually need. My today’s struggle: replacing a disk within a FreeBSD ZFS pool.

Hi there,

Ioctls are input/output control system calls and DRM stands for direct rendering manager The DRM layer provides several services to graphics drivers, many of them driven by the application interfaces it provides through libdrm, the library that wraps most of the DRM ioctls. These include vblank event handling, memory management, output management, framebuffer management, command submission & fencing, suspend/resume support, and DMA services.

NetBSD was able to make native DRM ioctl calls with hardware rendering once xorg and proper mesa packages where installed. We used the glxinfo and glxgears applications to test this out.

Discord users keep telling about their so called discord server, which is not dedicated to them at all. And Discord has a very bad quality and a lot of voice distorsion.

From time to time, I like to review my knowledge in a certain area, even when I feel like I know a lot about it already. I go back to the basics and read tutorials, manuals, books or watch interesting videos.

In preparation for a talk on Seventh Edition Unix this fall, I stumbled upon a service list from DEC for all known PDP-7 machines. From that list, and other sources, I believe that PDP-7 serial number 34 was the original Unix machine.

Upstream describes LLDB as a next generation, high-performance debugger. It is built on top of LLVM/Clang toolchain, and features great integration with it. At the moment, it primarily supports debugging C, C++ and ObjC code, and there is interest in extending it to more languages.

FreeBSD 11.3 has been released, OpenBSD workstation, write your own fuzzer for the NetBSD kernel, Exploiting FreeBSD-SA-19:02.fd, streaming to twitch using OpenBSD, 3 different ways of dumping hex contents of a file, and more.

The FreeBSD Release Engineering Team is pleased to announce the availability of FreeBSD 11.3-RELEASE. This is the fourth release of the stable/11 branch.

Why OpenBSD? Simply because it is the best tool for the job for me for my new-to-me Lenovo Thinkpad T420. Additionally, I do care about security and non-bloat in my personal operating systems (business needs can have different priorities, to be clear).

I will try to detail what my reasons are for going with OpenBSD (instead of GNU/Linux, NetBSD, or FreeBSD of which I’m comfortable using without issue), challenges and frustrations I’ve encountered, and what my opinions are along the way.

Disclaimer: in this post, I’m speaking about what is my opinion, and I’m not trying to convince you to use OpenBSD or anything else. I don’t truly care, but wanted to share in case it could be useful to you. I do hope you give OpenBSD a shot as your workstation, especially if it has been a while.

I’m not new to OpenBSD, to be clear. I’ve been using it off and on for over 20 years. The biggest time in my life was the early 2000s (I was even the Python port maintainer for a bit), where I not only used it for my workstation, but also for production servers and network devices.

I just haven’t used it as a workstation (outside of a virtual machine) in over 10 years, but have used it for servers. Workstation needs, especially for a primary workstation, are greatly different and the small things end up mattering most.

The easy way to describe fuzzing is to compare it to the process of unit testing a program, but with different input. This input can be random, or it can be generated in some way that makes it unexpected form standard execution perspective.

The simplest 'fuzzer' can be written in few lines of bash, by getting N bytes from /dev/rand, and putting them to the program as a parameter.

What can be done to make fuzzing more effective? If we think about fuzzing as a process, where we place data into the input of the program (which is a black box), and we can only interact via input, not much more can be done.

However, programs usually process different inputs at different speeds, which can give us some insight into the program's behavior. During fuzzing, we are trying to crash the program, thus we need additional probes to observe the program's behaviour.

Additional knowledge about program state can be exploited as a feedback loop for generating new input vectors. Knowledge about the program itself and the structure of input data can also be considered. As an example, if the input data is in the form of HTML, changing characters inside the body will probably cause less problems for the parser than experimenting with headers and HTML tags.

For open source programs, we can read the source code to know what input takes which execution path. Nonetheless, this might be very time consuming, and it would be much more helpful if this can be automated. As it turns out, this process can be improved by tracing coverage of the execution

You can submit your proposal at https://easychair.org/conferences/?conf=vbsdcon2019

The talks will have a very strong technical content bias. Proposals of a business development or marketing nature are not appropriate for this venue.

If you are doing something interesting with a BSD operating system, please submit a proposal. Whether you are developing a very complex system using BSD as the foundation, or helping others and have a story to tell about how BSD played a role, we want to hear about your experience. People using BSD as a platform for research are also encouraged to submit a proposal.

Possible topics include: How we manage a giant installation with respect to handling spam, snd/or sysadmin, and/or networking, Cool new stuff in BSD, Tell us about your project which runs on BSD.

Both users and developers are encouraged to share their experiences.

In February 2019 the FreeBSD project issued an advisory about a possible vulnerability in the handling of file descriptors. UNIX-like systems such as FreeBSD allow to send file descriptors to other processes via UNIX-domain sockets. This can for example be used to pass file access privileges to the receiving process.

Inside the kernel, file descriptors are used to indirectly reference a C struct which stores the relevant information about the file object. This could for instance include a reference to a vnode which describes the file for the file system, the file type, or the access privileges.

What really happens if a UNIX-domain socket is used to send a file descriptor to another process is that for the receiving process, inside the kernel a reference to this struct is created. As the new file descriptor is a reference to the same file object, all information is inherited. For instance, this can allow to give another process write access to a file on the drive even if the process owner is normally not able to open the file writable.

The advisory describes that FreeBSD 12.0 introduced a bug in this mechanism. As the file descriptor information is sent via a socket, the sender and the receiver have to allocate buffers for the procedure. If the receiving buffer is not large enough, the FreeBSD kernel attempts to close the received file descriptors to prevent a leak of these to the sender. However, while the responsible function closes the file descriptor, it fails to release the reference from the file descriptor to the file object. This could cause the reference counter to wrap.

The advisory further states that the impact of this bug is possibly a local privilege escalation to gain root privileges or a jail escape. However, no proof-of-concept was provided by the advisory authors.

The privilege escalation is now a piece of cake thanks to a technique used by kingcope, who published a FreeBSD root exploit in 2005, which writes to the file /etc/libmap.conf. This configuration file can be used to hook the loading of dynamic libraries if a program is started. The exploit therefore creates a dynamic library, which copies /bin/sh to another file and sets the suid-bit for the copy. The hooked library is libutil, which is for instance called by su. Therefore, a call to su by the user will afterwards result in a suid copy of /bin/sh.

If you ever wanted to make a twitch stream from your OpenBSD system, this is now possible, thanks to OpenBSD developer thfr@ who made a wrapper named fauxstream using ffmpeg with relevant parameters.

The setup is quite easy, it only requires a few steps and searching on Twitch website two informations, hopefully, to ease the process, I found the links for you.

You will need to make an account on twitch, get your api key (a long string of characters) which should stay secret because it allow anyone having it to stream on your account.

Am5x86 based retro UNIX build log, setting up services in a FreeNAS Jail, first taste of DragonflyBSD, streaming Netflix on NetBSD, NetBSD on the last G4 Mac mini, Hammer vs Hammer2, and more.

I have recently acquired an Am5x86 computer, in a surprisingly good condition. This is an ongoing project, check this page often for updates!

I began by connecting a front panel. The panel came from a different chassis and is slightly too wide, so I had to attach it with a couple of zip-ties. However, that makes it stick out from the PC front at an angle, allowing easy access when the computer sits at the floor - and thats where it is most of the time. It's not that bad, to be honest, and its way easier to access than it would be, if mounted vertically

There is a mains switch on the front panel because the computer uses an older style power supply. Those power supplies instead of relying on a PSON signal, like modern ATX supplies, run a 4 wire cable to a mains switch. The cable carries live and neutral both ways, and the switch keys in or out the power. The system powers on as soon as the switch is enabled.

Originally there was no graphics card in it. Since a PC will not boot with out a GPU, I had to find one. The mainboard only has PCI and ISA slots, and all the GPUs I had were AGP. Fortunately, I bought a PCI GPU hoping it would solve my issue...

However the GPU turned out to be faulty. It took me some time to repair it. I had to repair a broken trace leading to one of the EEPROM pins, and replace a contact in the EEPROM's socket. Then I replaced all the electrolytic capacitors on it, and that fixed it for good.

Having used up only one of the three PCI slots, I populated the remaining pair with two ethernet cards. I still have a bunch of ISA slots available, but I have nothing to install there. Yet.

This piece demonstrates the setup of a server service in a FreeNAS jail and how to share files with a jail using Apache 2.4 as an example. Jails are powerful, self-contained FreeBSD environments with separate network settings, package management, and access to thousands of FreeBSD application packages. Popular packages such as Apache, NGINX, LigHTTPD, MySQL, and PHP can be found and installed with the pkg search and pkg install commands.

This example shows creating a jail, installing an Apache web server, and setting up a simple web page.

NOTE: Do not directly attach FreeNAS to an external network (WAN). Use port forwarding, proper firewalls and DDoS protections when using FreeNAS for external web sites. This example demonstrates expanding the functionality of FreeNAS in an isolated LAN environment.

Last week, I needed to pick a BSD Operating System which supports NUMA to do some testing, so I decided to give Dragonfly BSD a shot. Dragonfly BSDonly can run on X86_64 architecture, which reminds me of Arch Linux, and after some tweaking, I feel Dragonfly BSD may be a “developer-friendly” Operating System, at least for me.

I mainly use Dragonfly BSD as a server, so I don’t care whether GUI is fancy or not. But I have high requirements of developer tools, i.e., compiler and debugger. The default compiler of Dragonfly BSD is gcc 8.3, and I can also install clang 8.0.0 from package. This means I can test state-of-the-art features of compilers, and it is really important for me. gdb‘s version is 7.6.1, a little lag behind, but still OK.

Furthermore, the upgradation of Dragonfly BSD is pretty simple and straightforward. I followed document to upgrade my Operating System to 5.6.0 this morning, just copied and pasted, no single error, booted successfully.

Here's a step-by-step guide that allows streaming Netflix media on NetBSD using a intel-haxm accelerated QEMU vm.

Heads-up! Sound doesn't work, but everything else is fine. Please read the rest of this thread for a solution to this!!

I’m about halfway through the new edition of Sudo Mastery. Assuming nothing terrible happens, should have a complete first draft in four to six weeks. Enough stuff has changed in sudo that I need to carefully double-check every single feature. (I’m also horrified by the painfully obsolete versions of sudo shipped in the latest versions of CentOS and Debian, but people running those operating systems are already accustomed to their creaky obsolescence.)

But the reason for this blog post? I have Eddie Sharam’s glorious cover art. My Patronizers saw it last month, so now the rest of you get a turn.

I'm a big fan of NetBSD. I've run it since 2000 on a Mac IIci (of course it's still running it) and I ran it for several years on a Power Mac 7300 with a G3 card which was the second incarnation of the Floodgap gopher server. Today I also still run it on a MIPS-based Cobalt RaQ 2 and an HP Jornada 690. I think NetBSD is a better match for smaller or underpowered systems than current-day Linux, and is fairly easy to harden and keep secure even though none of these systems are exposed to the outside world.

Recently I had a need to set up a bridge system that would be fast enough to connect two networks and I happened to have two of the "secret" last-of-the-line 1.5GHz G4 Mac minis sitting on the shelf doing nothing. Yes, they're probably outclassed by later Raspberry Pi models, but I don't have to buy anything and I like putting old hardware to good use.

With the newly released DragonFlyBSD 5.6 there are improvements to its original HAMMER2 file-system to the extent that it's now selected by its installer as the default file-system choice for new installations. Curious how the performance now compares between HAMMER and HAMMER2, here are some initial benchmarks on an NVMe solid-state drive using DragonFlyBSD 5.6.0.

With a 120GB Toshiba NVMe SSD on an Intel Core i7 8700K system, I ran some benchmarks of DragonFlyBSD 5.6.0 freshly installed with HAMMER2 and then again when returning to the original HAMMER file-system that remains available via its installer. No other changes were made to the setup during testing.

And then for the more synthetic workloads it was just a mix. But overall HAMMER2 was performing well during the initial testing and great to see it continuing to offer noticeable leads in real-world workloads compared to the aging HAMMER file-system. HAMMER2 also offers better clustering, online deduplication, snapshots, compression, encryption, and many other modern file-system features.

Website protection with OPNsense, FreeBSD Support Pull Request for ZFS-on-Linux, How much has Unix changed, Porting Wine to amd64 on NetBSD, FreeBSD Enterprise 1 PB Storage, the death watch for X11 has started, and more.

The OPNsense security platform can help you to protect your network and your webservers with the nginx plugin addition.

UNIX-like systems have dominated computing for decades, and with the rise of the internet and mobile devices their reach has become even larger. True, most systems now use more modern OSs like Linux, but how much has the UNIX-like landscape changed since the early days?

I have been working on porting Wine to amd64 on NetBSD as a GSoC 2019 project. Wine is a compatibility layer which allows running Microsoft Windows applications on POSIX-complaint operating systems. This report provides an overview of the progress of the project during the first coding period.

Today FreeBSD operating system turns 26 years old. 19 June is an International FreeBSD Day. This is why I got something special today :). How about using FreeBSD as an Enterprise Storage solution on real hardware? This where FreeBSD shines with all its storage features ZFS included.

Once we are done with this we expect X.org to go into hard maintenance mode fairly quickly. The reality is that X.org is basically maintained by us and thus once we stop paying attention to it there is unlikely to be any major new releases coming out and there might even be some bitrot setting in over time. We will keep an eye on it as we will want to ensure X.org stays supportable until the end of the RHEL8 lifecycle at a minimum, but let this be a friendly notice for everyone who rely the work we do maintaining the Linux graphics stack, get onto Wayland, that is where the future is.