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Mickaël Salaün an me will give a talk on recent Landlock developments at the upcoming Linux Security Summit Europe in Prague: Landlock gained a few interesting features to restrict more operations.

Linux 7.2 introduces the following Landlock features: Controls for UDP connect/send/bind operations (Matthieu Buffet) (Wiki, Docs) LANDLOCK_ADD_RULE_QUIET flag for landlock_add_rule(2) (Tingmao Wang) (Docs) Overview on the Landlock ABI Versioning Page

📢 I gave a talk about Go-Landlock and Multithreaded Policy Enforcement with LANDLOCK_RESTRICT_SELF_TSYNC at the Zurich Gophers Meetup on 2026-04-23.

Splitting a git commit is now easy, using: git history split ${REF} It will ask you hunk by hunk for the things to include in the first commit, and then bring up the editor for the first and second commit message.

I discussed previously that AI projects have a short lifespan, on average.

The Lindy Effect is a theorized phenomenon by which the future life expectancy of some non-perishable thing, like a technology or an idea, is proportional to its current age.

I did not expect that I’d quote the Catholic Church on this blog.

Objective Hypothesis Implementation Measurements Effects on Landlock code complexity Effects on Performance Noteworthy results: Conclusion Full results fs_bench net_bench scoped_bench Objective Landlock supports multiple nested sandboxes, so when an opera…

To extract text between two regular expressions, use sed -n '/first_regex/second_regex/p'.

With Linux 7.0, Landlock gains the new LANDLOCK_RESTRICT_SELF_TSYNC feature.

The big question for science is: Does it stay on the ground in the jar, or does it form floating lumps?

Is your test in the business of calculating the expected output from the inputs?

Mickaël’s FOSDEM talk about the Island sandboxing tool: https://fosdem.org/2026/schedule/event/EW8M3R-island/ (with 📽️ video!)

The time is overdue.

I will be at FOSDEM 2026 this year, with a hunger for Belgian waffles and a big bag of freshly printed Landlock stickers.

I am excited to share that my team at Google, Google Big Sleep, has published the reports for a few (now fixed) Linux kernel vulnerabilities: BIGSLEEP-458654612 BIGSLEEP-462435176 BIGSLEEP-463332873 The full public list of issues discovered by Google Big…

The following script takes an email on stdin and constructs the associated lore.kernel.org link based on the email’s Message-ID header.

The classic TCP client/server interaction When a TCP client calls connect(2), it usually gets assigned a port number from the ephemeral port range which is not used yet.

While I wasn’t looking, C23 has standardized checked integer arithmetic functions, replacing the old “__builtin_mul_overflow()” compiler intrinsics that shipped with GCC and Clang.

We’ve all heard the horror stories where an unsandboxed coding agent deletes the user’s entire home directory.

When I posted about the Emacs mouse bug in February, I looked into the patch set again, and of course spotted more mistakes.

I accidentally broke Emacs mouse support on the Linux console. o_O The TIOCLINUX patch for disabling dangerous IOCTLs for the Linux console driver (background discussed on the Wiki) ended up accidentally making the mouse cursor invisible on the Linux cons…

People have apparently started believing that in order to use git, you’d have to also have to host the project on Github or Gitlab: A few weeks ago, a friend told me that he keeps his pass password repository on Github.

Thoughts on sandboxing, found via Aaron Swartz’s weblog, who in turn found it in a writeup about Dan Bernstein’s 2005 research activities (at the end): The software installed on my newest home computer contains 78 million lines of C and C++ source code.

I will be attending the following conferences: Vintage Computer Festival Zurich, January 18-19, 2025 FOSDEM 2025, February 1-2, 2025 I am collecting a few interesting talks over on the wiki Obligatory Landlock talk: Sandbox IDs with Landlock We have Landl…

📢 I gave a talk about the recent changes in Landlock and its new support for restricting IOCTL usage at the Linux Security Summit Europe 2024 in Vienna: 🌍 Talk page | 🎥 Video on YouTube | 😎 We have stickers!

In the context of Alejandro Colomar stepping down as a man-pages maintainer :(, I learned from him that it is possible with git to create an email patch set that spans multiple target repositories.

📢 I will give a talk about the recent changes in Landlock and its new support for restricting IOCTL usage at the Linux Security Summit Europe 2024 in Vienna: The Landlock security module lets Linux processes restrict what they can do and puts developers in

Landlock’s IOCTL support for device files has landed in Linux 6.10 🚀.

This has always been true, but it begs repeating: Every docstring should provide additional information about the thing that it is documenting, which is not obvious from the thing’s name and its type information.

Introduction This feature is mis-documented /dev/fd/* behave different on other Unixes Part 1: An experiment!

In Linux 6.7, Konstantin Meskhidze introduced TCP Networking support for Landlock. 🚀 I am happy to announce that Go-Landlock is one of the first libraries using it, and it has a demo tool.

Twitter Posting: You can tweet, but the public can’t read it1.

I wrote a tool, Mailprint, for printing out nice-looking emails from Mutt and other classic Mail user agents.

Intro When I came back to the email account where I first subscribed to LKML, it was full.

This is less of a “Today I learned” article, but more like a Unix trick that took me too long to realize.

ABI versions and matching access rights The problem: Refer is different Implementation of best-effort fallback in C Common part: ABI version compatibility table Case 1: the sandboxed program does not need to reparent files Case 2: the sandboxed program ne…

Linus Torvalds released Linux 6.2 yesterday, and this kernel release supports restricting the truncate(2) and ftruncate(2) operations with Landlock.

Motivation Philosophy The Landlock approach 1.

So, there was a post by Justine Tunney about her port of OpenBSD’s pledge() to her own libc, the Cosmopolitan libc.

This explains how to configure multiple keyboards in Sway, and how to use advanced configuration when regular xkb_options are not enough.

This is a collection of interesting literature on the subject of error handling which I had collected to research my own blog post on the subject a while ago.

Linux 5.13 is going to include the unprivileged sandboxing feature Landlock, which has been in the making for many years now.

Tests should be correct by inspection Tests require a different approach than normal code.

If your plan is to loop over a collection: You shouldn’t check for it being non-empty first.

My toy Lisp fn is an inherently single-threaded language, but with its built-in stack-inspection capabilities, it’s easy to build coroutines on top.

Recently, almost all my digital drawings were made with a Bamboo Slate tablet and Tuhi.

In Go 1.14, the new T.Cleanup() function schedules defer-like work to be done after the current test.

The main technique in software design is this: You look at the entirety of your system and you decompose it into pieces that are more manageable and have clear interfaces.

Renaissance gopher Johannes Gopherberg after inventing html/template I’m using html/template much too seldom to remember how to properly share common template blocks across multiple pages.