I think OP is referring to the "unprivileged user namespaces" [1] feature of Linux, which caused numerous security incidents in the past. AFAIK, this is mainly because with this feature enabled, unprivilged users can create environments/namespaces which allow them to exploit kernel bugs much more easily. Most of them revolve around broken permission checks (read: root inside container but not outside, yet feature X falsely checks for the permissions _inside_). [2] has a nice list of CVEs caused by unprivileged user namespaces.
Given that rootful docker e.g. is also prone to causing security issues, it's ultimately an attacker model / pick-your-poison situation though.
My experience with Cpp isn't that extensive, but what is the use-case of a garbage collector in this language? I always had the impression that with the well-defined lifetimes of objects, you wouldn't really create garbage to begin with, but I guess there are some use-cases I don't yet know about?
It is worth noting that this release currently breaks the banIP package [1], which relies on the old fw3. So for those relying on it, it might be worth waiting for a short while.
Fascinating link, thank you!
On that note though: How are the horizontal bars (first one right below the introduction) made? My guess is that they gathered all colours from all pixels, made a histogram, and then converted that into a horizontal stacked bar. However, the ordering seems weird, as some colours look like they appear multiple times (say for example the almost black-ish regions), disproving my histogram hypothesis. Then again, that may be due to image compression. And ordering the colour vectors would highly depend on the used colour space & the used partial order.
I similarly stumbled over the image-version of these bars in section "The colours within a single object" further down, which I just don't quite understand how they're made.
Does someone have insight on the methodology or maybe a link to a paper? The present methodology section seems to focus on object similarity.
> Note: This blog post has been rewritten at least 3 times. I started with describing how I configured the system, then I went to bragging about how I love bspwm, how I set up all my jails, etc. I might still write about it at some point, but not this time. Every time I started writing the post, I realised that I was missing a point. I can say now that I know what I really wanted to say: that I love FreeBSD and I find joy in using it.
I really appreciate the honesty and I think it was a good choice to focus on fleshing out the message.
Also: Quite the un-evangelistic stance on this rather controversy-inducing topic!
What I found interesting is the ripple-like throughput fluctuations. Especially on the TX2 v8.1a, this seems very odd.
User 'MB' has already asked this on the sites forum, but the author could not explain it either.
Maybe someone on HN has an idea?
I took a university class on said book last year, held by one of the authors Prof. Tobias Nipkow.
Its a fascinating introduction into general program semantics, formal analyses and proofs for program properties.
During the lecture I struggled somewhat as I didn‘t really have sufficient background knowledge for it to run smoothly.
But all the concepts are supported by, well, concrete examples which you can immediately try to solve in Isabelle. So I definitely recommend giving it a go!
It was an eye-opening experience for me, especially since I never really looked into formal program analysis.
[1] https://www.man7.org/linux/man-pages/man7/user_namespaces.7....
[2] https://security.stackexchange.com/a/209533