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[$] A safer kmalloc() for 7.0
A pull request that touches over 8,000 files, changing over 20,000 lines of code in the process, is (fortunately) not something that happens every day. It did happen at the end of the 7.0 merge window, though, when Linus Torvalds merged an extensive set of changes by Kees Cook to the venerable kmalloc() API (and its users). As a result of that work, though, the kernel has a new set of type-safe memory-allocation functions, with a last-minute bonus change to make the API a little easier to use.
[$] More timing side-channels for the page cache
In 2019, researchers published a way to identify which file-backed pages were being accessed on a system using timing information from the page cache, leading to a handful of unpleasant consequences and a change to the design of the mincore() system call. Discussion at the time led to a number of ad-hoc patches to address the problem. The lack of new page-cache attacks suggested that attempts to fix things in a piecemeal fashion had succeeded. Now, however, Sudheendra Raghav Neela, Jonas Juffinger, Lukas Maar, and Daniel Gruss have found a new set of holes in the Linux kernel's page-cache-timing protections that allow the same general class of attack.
[$] Practical uses for a null filesystem
One of the first changes merged for the upcoming 7.0 release was nullfs, an empty filesystem that cannot actually contain any files. One might logically wonder why the kernel would need such a thing. It turns out, though, that there are places where a null filesystem can come in handy. For 7.0, nullfs will be used to make life a bit easier for init programs; future releases will likely use nullfs to increase the isolation of kernel threads from the init process.
[$] LWN.net Weekly Edition for March 12, 2026
Posted Mar 12, 2026 0:08 UTC (Thu)The LWN.net Weekly Edition for March 12, 2026 is available.
Inside this week's LWN.net Weekly Edition
- Front: Chardet; Linux and age verification; Debian AI; Python lazy imports; Python type-system PEP; PQC HTTPS certificates; MGLRU; Fedora strategy.
- Briefs: LLM vulnerability; NTP security; OpenWrt 25.12.0; SUSE sale; Buildroot 2026.02; digiKam 9.0.0; Rust 1.94.0; Quotes; ...
- Announcements: Newsletters, conferences, security updates, patches, and more.
[$] California's Digital Age Assurance Act and Linux distributions
A recently enacted law in California imposes an age-verification requirement on operating-system providers beginning next year. The language of the Digital Age Assurance Act does not restrict its requirements to proprietary or commercial operating systems; projects like Debian, FreeBSD, Fedora, and others seem to be on the hook just as much as Apple or Microsoft. There is some hope that the law will be amended, but there is no guarantee that it will be. This means that the developer communities behind Linux distributions are having to discuss whether and how to comply with the law with little time and even less legal guidance.
[$] HTTPS certificates in the age of quantum computing
There has been ongoing discussion in the Internet Engineering Task Force (IETF) about how to protect internet traffic against future quantum computers. So far, that work has focused on key exchange as the most urgent problem; now, a new IETF working group is looking at adopting post-quantum cryptography for authentication and certificate transparency as well. The main challenge to doing so is the increased size of certificates — around 40 times larger. The techniques that the working group is investigating to reduce that overhead could have efficiency benefits for traditional certificates as well.
[$] Disabling Python's lazy imports from the command line
The advent of lazy imports in the Python language is upon us, now that PEP 810 ("Explicit lazy imports") was accepted by the steering council and the feature will appear in the upcoming Python 3.15 release in October. There are a number of good reasons, performance foremost, for wanting to defer spending—perhaps wasting—the time to do an import before a needed symbol is used. However, there are also good reasons not to want that behavior, at least in some cases. The tension between those two positions is what led to an earlier PEP rejection, but it is also playing into a recent discussion of the API used to control lazy imports.
[$] Debian decides not to decide on AI-generated contributions
Debian is the latest in an ever-growing list of projects to wrestle (again) with the question of LLM-generated contributions; the latest debate stared in mid-February, after Lucas Nussbaum opened a discussion with a draft general resolution (GR) on whether Debian should accept AI-assisted contributions. It seems to have, mostly, subsided without a GR being put forward or any decisions being made, but the conversation was illuminating nonetheless.
[$] Inspecting and modifying Python types during type checking
Python has a unique approach to static typing. Python programs can contain type annotations, and even access those annotations at run time, but the annotations aren't evaluated by default. Instead, it is up to external programs to ascribe meaning to those annotations. The annotations themselves can be arbitrary Python expressions, but in practice usually involve using helpers from the built-in typing module, the meanings of which external type-checkers mostly agree upon. Yet the type system implicitly defined by the typing module and common type-checkers is insufficiently powerful to model all of the kinds of dynamic metaprogramming found in real-world Python programs. PEP 827 ("Type Manipulation") aims to add additional capabilities to Python's type system to fix this, but discussion of the PEP has been of mixed sentiment.
[$] Fedora shares strategy updates and "weird research university" model
In early February, members of the Fedora Council met in Tirana, Albania to discuss and set the strategic direction for the Fedora Project. The council has published summaries from its strategy summit, and Fedora Project Leader (FPL) Jef Spaleta, as well as some of the council members, held a video meeting to discuss outcomes from the summit on February 25. Topics included a plan to experiment with Open Collective to raise funds for specific Fedora projects, tools to build image-based editions, and more. Spaleta also explained his model for Fedora governance.
Debian Project Leader election underway
Kurt Roeckx has announced that Debian has moved to the campaigning period for the 2026 Debian Project Leader (DPL) election. This year there is only one candidate, Sruthi Chandran, so Debian voters will have a choice between Chandran as DPL or "None of the above". The campaign period will run through April 3, and the voting period will run from April 4 to April 17. Chandran has not yet posted a platform for the 2026 election, but her 2024 platform is available on the Debian wiki.
GIMP 3.2 released
After a year's worth of development since GIMP 3.0 was released, the team behind the open-source image editor has released GIMP 3.2. It comes as part of the plan to release GIMP more frequently, rather than wait six or seven years between releases. The release comes with lots of new features (as can be seen in more detail in the release notes), including 20 new brushes for the MyPaint Brush tool, an "overwrite" paint mode, new and upgraded file formats, UI improvements in a variety of places, such as the on-canvas text editor, and new non-destructive layers:
- You can now use Link Layers to incorporate external image as part of your compositions, easily scaling, rotating, and transforming them without losing quality or sharpness. The link layer's content is updated when the source file is modified
- The Path tool can now create Vector Layers, which lets you draw shapes with adjustable fill and stroke settings.
Security updates for Monday
Security updates have been issued by AlmaLinux (.NET 10.0, .NET 8.0, .NET 9.0, delve, git-lfs, gnutls, kernel, mingw-libpng, nfs-utils, opentelemetry-collector, python3.11, python3.12, python3.9, and vim), Debian (chromium, gimp, kernel, linux-6.1, and wireless-regdb), Fedora (alertmanager, chromium, freerdp, glab, golang-github-openprinting-ipp-usb, gst-devtools, gst-editing-services, gstreamer1, gstreamer1-doc, gstreamer1-plugin-libav, gstreamer1-plugins-bad-free, gstreamer1-plugins-base, gstreamer1-plugins-good, gstreamer1-plugins-ugly-free, gstreamer1-rtsp-server, insight, pcs, pgadmin4, python-gstreamer1, python3.10, python3.11, python3.6, qgis, SDL2_sound, SDL3_sound, systemd, and wireshark), Mageia (python-nltk, tomcat, and vim), Oracle (.NET 10.0, .NET 8.0, .NET 9.0, compat-openssl11, dtrace, python3.12, and vim), Red Hat (buildah, git-lfs, golang-github-openprinting-ipp-usb, opentelemetry-collector, podman, and runc), and SUSE (amazon-ssm-agent, busybox, clamav, firefox, giflib-devel-32bit, glibc, heroic-games-launcher, himmelblau, kubelogin, libpng15, libsoup, libsoup2, mingw32-binutils, mingw64-binutils, osc, obs-scm-bridge, python, python-black, python3, qemu, ruby4.0-rubygem-actioncable, ruby4.0-rubygem-actiontext, ruby4.0-rubygem-activejob, ruby4.0-rubygem-activemodel, tomcat, and tomcat10).
Kernel prepatch 7.0-rc4
Linus has released 7.0-rc4 for testing.
Then Thursday hit with the networking pull. And then on Friday everybody else decided to send in their work for the week, with a few more trickling in over the weekend. End result: what had for a short few days looked like a nice calm week turned into another "bigger than usual" release candidate.To be fair, that "almost everything comes in at the end of the week" is 100% normal, and none of this is surprising. I was admittedly hoping that things would start to calm down, but that was not to be.
I no longer really believe that it was the one extra week we had last release cycle: I'm starting to suspect it's the psychological result of "hey, new major number", and people are just being a bit more active as a result.
Stable kernels for Friday the 13th
Greg Kroah-Hartman has announced the release of the 6.19.8, 6.18.18, and 6.12.77 stable kernels. Each of these kernels includes a number of important fixes; users are advised to upgrade.
An investigation of the forces behind the age-verification bills
Reddit user "Ok_Lingonberry3296" has posted the results of an extensive investigation into the companies that are pushing US state legislatures to enact age-verification bills.
I've been pulling public records on the wave of "age verification" bills moving through US state legislatures. IRS 990 filings, Senate lobbying disclosures, state ethics databases, campaign finance records, corporate registries, WHOIS lookups, Wayback Machine archives. What started as curiosity about who was pushing these bills turned into documenting a coordinated influence operation that, from a privacy standpoint, is building surveillance infrastructure at the operating system level while the company behind it faces zero new requirements for its own platforms.
(See also this article for a look at the California law.)
A set of AppArmor vulnerabilities
Qualys has sent out a somewhat breathless advisory describing a number of vulnerabilities in the AppArmor security module, which is used in a number of Debian-based distributions (among others).
This "CrackArmor" advisory exposes a confused-deputy flaw allowing unprivileged users to manipulate security profiles via pseudo-files, bypass user-namespace restrictions, and execute arbitrary code within the kernel. These flaws facilitate local privilege escalation to root through complex interactions with tools like Sudo and Postfix, alongside denial-of-service attacks via stack exhaustion and Kernel Address Space Layout Randomization (KASLR) bypasses via out-of-bounds reads.
Security updates for Friday
Security updates have been issued by Debian (chromium, kernel, and multipart), Fedora (dnf5, dr_libs, easyrpg-player, libmaxminddb, python3.12, strongswan, task, and udisks2), Oracle (.NET 10.0, .NET 8.0, .NET 9.0, gnutls, ImageMagick, kernel, libvpx, mingw-libpng, nginx:1.26, python3.11, and uek-kernel), Red Hat (delve, git-lfs, mingw-libpng, osbuild-composer, and rhc-worker-playbook), SUSE (cjson, curl, dnsdist, libsoup2, postgresql16, postgresql17, postgresql18, python-lxml_html_clean, python-pypdf2, python36, and thunderbird), and Ubuntu (dotnet8, dotnet9, dotnet10, freetype, golang-github-go-git-go-git, golang-golang-x-net, openssh, python-cryptography, sudo, and util-linux).
Two stable kernels for Thursday
Sasha Levin has announced the release of the 6.19.7 and 6.18.17 stable kernels. As usual, each contains important fixes throughout the tree; users are advised to upgrade.
Security updates for Thursday
Security updates have been issued by AlmaLinux (gimp, git-lfs, grafana-pcp, kernel, mysql8.4, nfs-utils, opentelemetry-collector, osbuild-composer, postgresql:16, and python3.12), Debian (imagemagick and netty), Fedora (dr_libs and python-lxml-html-clean), Slackware (libarchive and libxml2), SUSE (busybox, coredns, firefox, freerdp, ghostty, gnutls, go1.25, go1.26, GraphicsMagick, grype, helm, helm3, ImageMagick, perl-Compress-Raw-Zlib, python, python311-lxml_html_clean, python311-PyPDF2, tomcat11, and traefik), and Ubuntu (curl, gimp, and libpng).