> Pondering the disastrous fate of the HP TouchPad, an early tablet based on WebOS that’s best known for being the subject of a well-remembered fire sale.

> So you tell me: Was this somebody carrying out an elaborate prank or somebody who simply didn’t understand what they were doing?

> Whether it was intended as such or not, this ended up being an effective denial-of-service attack against me personally, since I ended up spending quite a bit of time watching the videos closely, then reverse-engineering what the finder believed the vulnerability to be, and then studying the videos again to find out where they went wrong.

I was feeling frustrated just reading the story.

> This case deals with a venerable and vexing copyright law problem: if a person doesn’t own the copyright to his/her tattoos, do other people infringe by accurately depicting the person? The answer surely has to be “no.” Otherwise, ordinary daily activities, such as photos and videos in public, become an unnavigable thicket of potential liability. Fortunately, this case decisively reaches the right result. However, it’s unclear how much it predicts future cases.

> In January 2018, the world learned about Spectre and Meltdown, a new class of issues that affects virtually all modern CPUs via nearly imperceptible changes to their micro-architectural states and can result in full access to physical RAM or leaking of state between threads, processes, or guests. In this session, we examine one of these side-channel attacks in detail and explore the implications for multi-tenant computing. We discuss AWS design decisions and what AWS does to protect your instances, containers, and function invocations. Finally, we discuss what the future looks like in the presence of this new class of issue.

This is a good recap. Specific defenses starts around 42:00.

> This article is about how pipes are implemented the Unix kernel. I was a little disappointed that a recent article titled “How do Unix pipes work?” was not about the internals, and curious enough to go digging in some old sources to try to answer the question.

source: HN

> Since this dates from early 2018, I believe it’s in everything from OpenBSD 6.4 onward. It’s definitely in OpenBSD 6.6. This new CPU time category is supported in OpenBSD’s versions of top and systat, but it is not explicitly broken out by vmstat; in fact vmstat’s ‘sy’ time is actually the sum of OpenBSD ‘system’, ‘interrupt’, and ‘spinning’. Third party tools may or may not have been updated to add this new category.

> The logic responsible for handling ->exit_signal has been changed a few times and the current logic is locked down since Linux kernel 3.3.5. However, it is not fully robust and it’s still possible for the malicious user to bypass it. Basically, it’s possible to send arbitrary signals to a privileged (suidroot) parent process (Problem I.). Nevertheless, it’s not trivial and more limited comparing to the CVE-2009-1337.

source: solar

> This code gets a list of all memory maps from /proc/self/maps, then creates a new executable map where it jits some code that calls munmap() on each of the maps it just got, and finally on the map it’s on. This is just a quick example with no portability in mind, so the source code contains the actual bytes that would be emitted by a x64 compiler. After unmapping the final map, where the jit code lies, there’s no new instruction to execute and a segfault is raised.

source: HN

> The goals of high throughput and low latency conflict with each other. To get best throughput, a compiler needs to spend time on code motion, register allocation, and instruction selection; to get low latency, that’s exactly what a compiler should not do. Web browsers therefore take a two-pronged approach: they have a compiler optimized for throughput, and a compiler optimized for latency. As a WebAssembly file is being downloaded, it is first compiled by the quick-and-dirty low-latency compiler, with the goal of producing machine code as soon as possible. After that “baseline” compiler has run, the “optimizing” compiler works in the background to produce high-throughput code. The optimizing compiler can take more time because it runs on a separate thread. When the optimizing compiler is done, it replaces the baseline code. (The actual heuristics about whether to do baseline + optimizing (“tiering“) or just to go straight to the optimizing compiler are a bit hairy, but this is a summary.)

> This article is about the WebAssembly baseline compiler in Firefox. It’s a surprising bit of code and I learned a few things from it.

source: HN

> Large-scale social experiments are now ubiquitous, and conducted without public scrutiny. Has this new era of experimentation remembered the lessons of the old?

> Physics, chemistry, and medicine have had their revolution. But now, driven by experimentation, a further transformation is in the air. That’s the argument of “The Power of Experiments” (M.I.T.), by Michael Luca and Max H. Bazerman, both professors at the Harvard Business School. When it comes to driving our decisions in a world of data, they say, “the age of experiments is only beginning.”

> In this paper I present an analysis of 1,976 unsolicited answers received from the targets of a malicious email campaign, who were mostly unaware that they were not contacting the real sender of the malicious messages. I received the messages because the spammers, whom I had described previously on my blog, decided to take revenge by putting my email address in the ‘reply-to’ field of a malicious email campaign. Many of the victims were unaware that the message they had received was fake and contained malware. Some even asked me to resend the malware as it had been blocked by their anti-virus product. I have read those 1,976 messages, analysed and classified victims’ answers, and present them here. The key takeaway is that we need to train users, but at the same time we should not count on them to react properly to Internet threats. Despite dealing with cybercrime victims daily for the last seven years I was surprised by most of the reactions and realized how little we, as the security industry, know about the average Internet user’s ability (or rather inability) to identify threats online. We need to build solutions that will protect users, without their knowledge, sometimes against their will, from their ability to harm themselves.

> The fifth group is actually the most worrying. I call this group ‘MY ANTI-VIRUS WORKED, PLEASE SEND AGAIN’, as these are recipients who mention that their security product (mostly anti-virus) warned them against an infected file, but they wanted the file to be resent because they could not open it. The group consisted of 44 individuals (2.35%).

source: grugq

> At one point we noticed that our disks were not as fast as we would like them to be. Some profiling as well as a quick A/B test pointed to Linux disk encryption. Because not encrypting the data (even if it is supposed-to-be a public Internet cache) is not a sustainable option, we decided to take a closer look into Linux disk encryption performance.

> To be fair the request does not always traverse all these queues, but the important part here is that write requests may be queued up to 4 times in dm-crypt and read requests up to 3 times. At this point we were wondering if all this extra queueing can cause any performance issues. For example, there is a nice presentation from Google about the relationship between queueing and tail latency. One key takeaway from the presentation is: A significant amount of tail latency is due to queueing effects

source: HN

> In the end, this random number generator was quickly removed, and that was that. But one can still wonder—is this generator secure but unanalyzed, or would it have been broken just to prove a point?

source: R

> The goal of this talk is to broaden the awareness of the how and why container escapes work, starting from a brief intro to what makes a process a container, and then spanning the gamut of escape techniques, covering exposed orchestrators, access to the Docker socket, exposed mount points, /proc, all the way down to overwriting/exploiting the kernel structures to leave the confines of the container.

source: white

> Knowing how relatively calm the situation has been here in the Netherlands (especially in Haarlem, where there is one reported case), we at Bellingcat felt that the video was likely fake — and set out to prove it.

> Their argument was simple. How could these disasters have happened with such regularity if the agency had not been penetrated by Soviet moles? The problem with this line of thought was that it did not so much overestimate CIA security as underestimate the brainpower of their Russian counterparts.

source: grugq

> First, the linuxulator is not an emulation. It is “just” a binary interface which is a little bit different from the FreeBSD-“native”-one. This means that the binary files in FreeBSD and Linux are both files which comply to the ELF specification.

source: vermaden

> oxbar is a X11 status bar for OpenBSD showing various system stats. It has a configurable display and works out-of-the-box on most modern window managers in an intuitive fashion. oxbar supports FreeType font rendering and styling, true transparency & alpha blending on all UI components (including the root window), and a simple configuration format that can concisely support multiple themes.

source: vermaden

> The goal for my infrastructure is to run the services I need. While a lot of people in the homelab community experiment and play with software for its own sake, I actively use the stuff I host. When I stop, I kill the service (though I’m not as proficient at this as Google). These are my production systems, and when one of them is down, I do miss it.

source: vermaden

> A decade after Doom’s release, in 2003, journalist David Kushner published a book about id Software called Masters of Doom, which has since become the canonical account of Doom’s creation. I read Masters of Doom a few years ago and don’t remember much of it now, but there was one story in the book about lead programmer John Carmack that has stuck with me. This is a loose gloss of the story (see below for the full details), but essentially, early in the development of Doom, Carmack realized that the 3D renderer he had written for the game slowed to a crawl when trying to render certain levels. This was unacceptable, because Doom was supposed to be action-packed and frenetic. So Carmack, realizing the problem with his renderer was fundamental enough that he would need to find a better rendering algorithm, started reading research papers. He eventually implemented a technique called “binary space partitioning,” never before used in a video game, that dramatically sped up the Doom engine.

History of research into BSP.