Linux Weekly News

Joel Severin has announced the availability of his port of the Linux kernel to WebAssembly; one can go to this page and watch it boot in a browser.

Wasm is similar to every other arch in Linux, but also different. One important difference is that there is no way to suspend execution of a task. There is a way around this though: Linux supports up to 8k CPUs (or possibly more...). We can just spin up a new CPU dedicated to each user task (process/thread) and never preempt it

Security updates have been issued by AlmaLinux (.NET 8.0, .NET 9.0, and webkit2gtk3), Debian (ruby-rack, strongswan, ublock-origin, and wordpress), Fedora (firefox, kea, openapi-python-client, openbao, python-uv-build, qt5-qtbase, ruby, ruff, rust-astral-tokio-tar, rust-attribute-derive, rust-attribute-derive-macro, rust-backon, rust-collection_literals, rust-get-size-derive2, rust-get-size2, rust-interpolator, rust-manyhow, rust-manyhow-macros, rust-proc-macro-utils, rust-quote-use, rust-quote-use-macros, rust-reqsign, rust-reqsign-aws-v4, rust-reqsign-command-execute-tokio, rust-reqsign-core, rust-reqsign-file-read-tokio, rust-reqsign-http-send-reqwest, rust-tikv-jemalloc-sys, rust-tikv-jemallocator, samba, skopeo, sssd, Thunar, unbound, uv, vgrep, and xorg-x11-server-Xwayland), Mageia (bind, libtiff, sope, and transfig), Oracle (compat-libtiff3, kernel, libtiff, redis, redis:6, and redis:7), Red Hat (kernel, kernel-rt, libssh, xorg-x11-server, and xorg-x11-server-Xwayland), Slackware (seamonkey), SUSE (bind, chromedriver, chromium, colord, coreboot-utils, git-bug, ImageMagick, java-11-openj9, java-17-openj9, java-21-openj9, java-25-openj9, kea, libmozjs-115-0, libmozjs-140-0, libssh, libtiff-devel-32bit, nodejs18, ongres-scram, poppler, python311-starlette, rav1e, squid, strongswan, webkit2gtk3, xorg-x11-server, and xwayland), and Ubuntu (linux-gcp-6.14 and linux-hwe-6.8).

Linus has released 6.18-rc4 for testing. "Last week in fact felt *so* calm that I was surprised to notice that rc4 isn't really smaller than usual: all the stats look very normal, both in number of changes and where the changes are."

The relatively small 6.17.7, 6.12.57, and 6.6.116 stable kernels have been released; each contains another set of important fixes.

Julian Andres Klode has announced that the Debian APT package-management tool will acquire "hard Rust dependencies sometime after May 2026. "If you maintain a port without a working Rust toolchain, please ensure it has one within the next 6 months, or sunset the port."

The idea of automatic syntax-aware merging in version-control systems goes back to 2005 or earlier, but initial implementations were often language-specific and slow. Mergiraf is a merge-conflict resolver that uses a generic algorithm plus a small amount of language-specific knowledge to solve conflicts that Git's default strategy cannot. The project's contributors have been working on the tool for just under a year, but it already supports 33 languages, including C, Python, Rust, and even SystemVerilog.

Michael Hudson-Doyle, a member of Ubuntu's Foundations team, has announced the introduction of an "architecture variant" for Ubuntu 25.10:

By making changes to dpkg, apt and Launchpad, we are able to build multiple versions of a package, each for a different level of the x86-64 architecture, meaning we can have packages that specifically target x86-64-v3, for example.

As a result, we're very excited to share that in Ubuntu 25.10, some packages are available, on an opt-in basis, in their optimized form for the more modern x86-64-v3 architecture level.

See the announcement for details on opting in to x86-64-v3 packages.

Security updates have been issued by AlmaLinux (java-1.8.0-openjdk, java-17-openjdk, libtiff, redis, and redis:6), Debian (chromium, mediawiki, pypy3, and squid), Fedora (openbao), SUSE (cdi-apiserver-container, cdi-cloner-container, cdi- controller-container, cdi-importer-container, cdi-operator-container, cdi- uploadproxy-container, cdi-uploadserver-container, cont, chromium, chrony, expat, haproxy, himmelblau, ImageMagick, iputils, kernel, libssh, libxslt, openssl-3, podman, strongswan, xorg-x11-server, and xwayland), and Ubuntu (kernel, libxml2, libyaml-syck-perl, linux, linux-aws, linux-aws-hwe, linux-gcp, linux-gcp-4.15, linux-hwe, linux-oracle, linux-fips, linux-aws-fips, linux-gcp-fips, linux-kvm, and netty).

Version 1.91.0 of the Rust language has been released. Changes include promoting aarch64-pc-windows-msvc to a tier-1 platform, a new lint rule to catch dangling raw pointers from local variables, and a fair number of newly stabilized APIs.

The kernel's file-I/O subsystems have been highly optimized over the years in the hope of providing the best performance for a wide variety of workloads. There is, however, one workload type that suffers with current kernels: applications that perform many short reads, in multiple processes, from the same file. Kiryl Shutsemau has been working on a patch to try to optimize this case, but the task is turning out to be harder than one might expect.

The Universal Blue project has announced the Fall update for the Fedora-based Bazzite gaming distribution. This release brings Bazzite up to Fedora 43, includes support for additional handheld gaming systems, as well as drivers for a number of steering wheel devices, and more.

Security updates have been issued by AlmaLinux (java-21-openjdk and libtiff), Debian (pdns-recursor and xorg-server), Fedora (bind, bind-dyndb-ldap, dtk6core, dtk6gui, dtk6log, dtk6widget, fcitx5-qt, fluidsynth, gammaray, kddockwidgets, LabPlot, mingw-qt6-qt3d, mingw-qt6-qt5compat, mingw-qt6-qtactiveqt, mingw-qt6-qtbase, mingw-qt6-qtcharts, mingw-qt6-qtdeclarative, mingw-qt6-qtimageformats, mingw-qt6-qtlocation, mingw-qt6-qtmultimedia, mingw-qt6-qtpositioning, mingw-qt6-qtscxml, mingw-qt6-qtsensors, mingw-qt6-qtserialport, mingw-qt6-qtshadertools, mingw-qt6-qtsvg, mingw-qt6-qttools, mingw-qt6-qttranslations, mingw-qt6-qtwebchannel, mingw-qt6-qtwebsockets, nheko, python-pyqt6, qt-creator, qt6, qt6-qt3d, qt6-qt5compat, qt6-qtbase, qt6-qtcharts, qt6-qtcoap, qt6-qtconnectivity, qt6-qtdatavis3d, qt6-qtdeclarative, qt6-qtgrpc, qt6-qthttpserver, qt6-qtimageformats, qt6-qtlanguageserver, qt6-qtlocation, qt6-qtlottie, qt6-qtmqtt, qt6-qtmultimedia, qt6-qtnetworkauth, qt6-qtopcua, qt6-qtpositioning, qt6-qtquick3d, qt6-qtquick3dphysics, qt6-qtquicktimeline, qt6-qtremoteobjects, qt6-qtscxml, qt6-qtsensors, qt6-qtserialbus, qt6-qtserialport, qt6-qtshadertools, qt6-qtspeech, qt6-qtsvg, qt6-qttools, qt6-qttranslations, qt6-qtvirtualkeyboard, qt6-qtwayland, qt6-qtwebchannel, qt6-qtwebengine, qt6-qtwebsockets, qt6-qtwebview, unbound, xorg-x11-server-Xwayland, and zeal), Oracle (kernel and libtiff), Red Hat (redis:6), Slackware (tigervnc and xorg), SUSE (java-21-openjdk, java-25-openjdk, strongswan, and xorg-x11-server), and Ubuntu (amd64-microcode, binutils, and xorg-server, xwayland).

Inside this week's LWN.net Weekly Edition:

• Front: Pixnapping attack; Fil-C; Debian ftpmasters; GoFundMe complaints; Safer user-space access.
• Briefs: Man pages 6.16; Btrfs on AlmaLinux; Fedora Linux 43; ICANN report; PSF grants; Rust Coreutils 0.3.0; Tor Browser 15.0; Quotes; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

Alejandro Colomar has announced the release of version 6.16 of the GNU/Linux man pages. This release includes new or rewritten man pages for fsconfig(), fsmount(), and fsopen(), as well as a number of newly documented interfaces in existing man pages. The release is also available as a PDF book.

ICANN's Security and Stability Advisory Committee (SSAC) has announced a report on "the critical role of Free and Open Source Software (FOSS) within the Domain Name System (DNS)". The report is aimed at policymakers and examines recent cybersecurity regulations in the US, UK, and EU as they apply to FOSS in the DNS system; it includes findings and guidelines "to strengthen the FOSS ecosystem that is critical to the secure and stable operation of the Internet". From the report's summary:

This ecosystem depends on a global network of maintainers and contributors who are often unpaid volunteers. While many are unpaid volunteers, the DNS space is unique in also relying on a handful of long-lived maintenance organizations. This creates a model based on community collaboration rather than the commercial contracts that define a traditional software supply chain, which introduces unique risks related to financial sustainability for the maintenance organizations and maintainer burnout for volunteers.

These unique characteristics mean that regulatory frameworks designed for proprietary software may not be well-suited for FOSS and therefore could have severe unintended consequences to the stability of critical Internet infrastructure.

Thanks to SSAC member Maarten Aertsen for the tip.

A new class of attacks on Android phones, called "Pixnapping", was announced on October 13. It allows a malicious app to gather output rendered in a victim app, pixel-by-pixel, by exploiting a GPU side-channel. Depending on what the victim app displays, anything from sensitive email and chats to two-factor authentication (2FA) codes could be captured—and shipped off to an attacker's site.

Version 15.0 of the Tor Browser has been released:

This is our first stable release based on Firefox ESR 140, incorporating a year's worth of changes that have been shipped upstream in Firefox. As part of this process, we've also completed our annual ESR transition audit, where we reviewed and addressed around 200 Bugzilla issues for changes in Firefox that may negatively affect the privacy and security of Tor Browser users. Our final reports from this audit are now available in the tor-browser-spec repository on our GitLab instance.

This release inherits the vertical tabs feature, unified search button, as well as other new features and usability improvements in Firefox that have passed the Tor Project's audit.

Debian's ftpmaster team has been responsible for allowing new packages to enter Debian, removing old packages, and otherwise maintaining Debian's package archive for more than two decades. As of October 26, the team is no more and its duties are being split between two new teams. The Archive Operations Team will focus on the infrastructure required to support the Debian archives, and the DFSG, Licensing & New Packages Team, which is responsible for reviewing packages entering the new queue. In time, this move could speed up processing of new packages, as well as making the teams more sustainable, but only after new members are recruited and trained. For now, the same folks are doing the work but spread across two teams.

Greg Kroah-Hartman has announced the release of the 6.17.6, 6.12.56, 6.6.115, 6.1.158, 5.15.196, 5.10.246, and 5.4.301 stable kernels. As always, each contains important fixes throughout the tree. Users of these kernels are advised to upgrade.

Security updates have been issued by Debian (gimp, python-authlib, and xorg-server), Fedora (chromium and git-lfs), Mageia (poppler and tomcat), Red Hat (kernel, kernel-rt, redis, and redis:6), SUSE (fetchmail, grafana, ImageMagick, kernel-devel, libluajit-5_1-2, proxy-helm, python-Authlib, and xen), and Ubuntu (linux-intel-iotg, linux-intel-iotg-5.15 and squid, squid3).