Linux Weekly News

GNU GRUB 2, mostly just referred to as GRUB these days, is the most widely used boot loader for x86_64 Linux systems. It supports reading from a vast selection of filesystems, handles booting modern systems with UEFI or legacy systems with a BIOS, and even allows users to customize the "splash" image displayed when a system boots. Alas, all of those features come with a price; GRUB has had a parade of security vulnerabilities over the years. To mitigate some of those problems, Ubuntu core developer and Canonical employee Julian Andres Klode has proposed removing a number of features from GRUB in Ubuntu 26.10 to improve GRUB's security profile. His proposal has not been met with universal acclaim; many of the features Klode would like to remove have vocal proponents.

On April 1, the Gentoo Linux project published a blog post announcing that it was switching to GNU Hurd as its primary kernel as an April Fool's joke. While that is not true, the project has followed up with an announcement of a new Gentoo port to the Hurd:

Our crack team has been working hard to port Gentoo to the Hurd and can now share that they've succeeded, though it remains still in a heavily experimental stage. You can try Gentoo GNU/Hurd using a pre-prepared disk image. The easiest way to do this is with QEMU [...]

We have developed scripts to build this image locally and conveniently work on further development of the Hurd port. Release media like stages and automated image builds are future goals, as is feature parity on x86-64. Further contributions are welcome, encouraged, and needed. Be patient, expect to get your hands dirty, anticipate breakage, and have fun!

Oh, and Gentoo GNU/Hurd also works on real hardware!

Text for the April Fool's post is available at the bottom of the real announcement.

Security updates have been issued by AlmaLinux (freerdp, grafana, kernel, rsync, and thunderbird), Debian (chromium, inetutils, and libpng1.6), Fedora (bind9-next, nginx-mod-modsecurity, and openbao), Mageia (firefox, nss and thunderbird), Red Hat (container-tools:rhel8), SUSE (conftest, dnsdist, ignition, libsoup, libsoup2, LibVNCServer, libXvnc-devel, opensc, ovmf-202602, perl-Crypt-URandom, python-tornado, python311-ecdsa, python311-Pygments, python315, tar, and wireshark), and Ubuntu (cairo, jpeg-xl, linux, linux-aws, linux-aws-6.17, linux-gcp, linux-gcp-6.17, linux-hwe-6.17, linux-realtime, linux, linux-aws, linux-aws-hwe, linux-kvm, linux-oracle, linux, linux-aws, linux-gcp, linux-gke, linux-gkeop, linux-ibm, linux-lowlatency, linux-nvidia, linux-raspi, linux-fips, linux-fips, linux-aws-fips, linux-fips, linux-aws-fips, linux-gcp-fips, and linux-realtime, linux-realtime-6.8, linux-raspi-realtime).

Denver Gingerich of the Software Freedom Conservancy (SFC) has published an article on the impact of the ban on the sale of all new home routers not made in the United States issued by the Federal Communications Commission (FCC). The SFC, of course, is the organization behind the OpenWrt One router.

Since software updates to already-FCC-approved devices do not require a new FCC approval, it appears the FCC is trying to move beyond its usual authorization procedures to restrict what manufacturers are allowed to push to existing routers. However, the FCC notably does not restrict software changes made by owners of routers in the U.S. In particular, there is no indication that updates people make to their own routers, using software they have sourced themselves, would run afoul of any past or present FCC rule.

As a result, we do not believe that this new FCC decision affects whether and how people can run OpenWrt or other user-selected firmware updates on routers they have already purchased. Not only is this an important right in relation to our ownership and control of our own devices, it also ensures that people can keep their routers secure for far longer than the manufacturer may choose to provide security updates, by allowing them to install up-to-date community software that supports routers for 10, 15, or even more years after their initial release date, as OpenWrt does for many devices.

He also notes that, as the OpenWrt One is already FCC-approved, there should be no impact on its availability in the US. The SFC has asked the FCC for clarification and plans to provide updates when they receive a reply.

The kernel provides a number of ways for processes to communicate with each other, but they never quite seem to fit the bill for many users. There are currently a few proposals for interprocess communication (IPC) enhancements circulating on the mailing lists. The most straightforward one adds a new system call for POSIX message queues that enables the addition of new features. For those wanting an entirely new way to do interprocess communication, there is a proposal to add a new subsystem for that purpose to io_uring. Finally, the bus1 proposal has made a return after ten years.

Brian "bex" Exelbierd has published a blog post exploring follow-up questions raised by the recent debate about the use of the LLM-based review tool Sashiko in the memory-management subsystem. His main finding is that Sashiko reviews are bi-modal with regards to whether they contain reports about code not directly changed by the patch set — most do not, but the ones that do often have several such comments.

Hypothesis 1: Reviewers are getting told about bugs they didn't create. Sashiko's review protocol explicitly instructs the LLM to read surrounding code, not just the diff. That's good review practice — but it means the tool might flag pre-existing bugs in code the patch author merely touched, putting those problems in their inbox.

Hypothesis 2: The same pre-existing bugs surface repeatedly. If a known issue in a subsystem doesn't get fixed between review runs, every patch touching nearby code could trigger the same finding. That would create a steady drip of duplicate noise across the mailing list.

I pulled data from Sashiko's public API and tested both.

OpenSSH 10.3 has been released. Among the many changes in this release are a security fix to address late validation of metacharacters in user names, removal of bug compatibility for SSH implementations that do not support rekeying, and a fix to ensure that scp clears setuid/setgid bits from downloaded files when operating as root in legacy (-O) mode. See the release announcement for a full list of new features, bug fixes, and potentially incompatible changes.

Security updates have been issued by AlmaLinux (python3.11, python3.12, squid, and thunderbird), Debian (gst-plugins-bad1.0 and gst-plugins-ugly1.0), Fedora (bpfman, crun, gnome-remote-desktop, polkit, python3.14, rust-rustls-webpki, rust-sccache, rust-scx_layered, rust-scx_rustland, rust-scx_rusty, and scap-security-guide), Oracle (freerdp, gstreamer1-plugins-bad-free, gstreamer1-plugins-base, gstreamer1-plugins-good, and gstreamer1-plugins-ugly-free, kernel, libxslt, python3.11, python3.12, squid, and thunderbird), SUSE (389-ds, busybox, chromium, cosign, curl, docker-compose, exiv2, expat, firefox, freerdp, freerdp2, gstreamer-plugins-ugly, harfbuzz, heroic-games-launcher, ImageMagick, kea, keylime, libjxl, librsvg, libsodium, libsoup, net-snmp, net-tools, netty, nghttp2, poppler, postgresql13, postgresql16, postgresql17, postgresql18, protobuf, python-black, python-orjson, python-pyasn1, python-pyOpenSSL, python-tornado, python-tornado6, python311-nltk, thunderbird, tomcat10, tomcat11, vim, and xen), and Ubuntu (kernel, linux, linux-aws, linux-kvm, linux-lts-xenial, linux-raspi, linux-raspi, linux-raspi-realtime, rust-cargo-c, rust-tar, and undertow).

Greg Kroah-Hartman has released the 6.19.11, 6.18.21, 6.12.80, and 6.6.131 stable kernels, followed by a quick release of 6.6.132 with two patches reverted to address a problem building the rust core in 6.6.131. Each kernel contains important fixes; users are advised to upgrade.

Inside this week's LWN.net Weekly Edition:

• Front: LiteLLM compromise; systemd controversy; LLM kernel review; OpenBSD and vibe-coding; Rust trait-solver; Pandoc.
• Briefs: Rspamd 4.0.0; telnyx vulnerability; Fedora forge; SystemRescue 13.00; Servo 0.0.6; Quotes; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

Michael Meeks has posted an angry missive about changes at The Document Foundation. What has really happened is not entirely clear, but it seems to involve, at a minimum, the forced removal of all Collabora staff from the foundation. There has been a set of "thank you" notes to the people involved posted in the foundation's forums. The Document Foundation's decision to restart LibreOffice Online almost certainly plays into this as well.

Details are fuzzy at best; we will be working at providing a clearer picture, but that will take some time.

Pandoc is a document-conversion program that can translate among a myriad of formats, including LaTeX, HTML, Office Open XML (docx), plain text, and Markdown. It is also extensible by writing Lua filters that can manipulate the document structure and perform arbitrary computations. Pandoc has appeared in various LWN articles over the years, such as my look at Typst and at the importance of free software to science in 2025, but we have missed providing an overview of the tool. The February release of Pandoc 3.9, which comes with the ability to compile the program to WebAssembly (Wasm), allowing Pandoc to run in web browsers, will likely also be of interest.

Version 0.0.6 of the Rust-based Servo web browser rendering engine has been released. This release boasts a long list of new features, performance enhancements, improvements, and bug fixes. Some of the notable changes include layout performance improvements, a servo:config page for setting any preference, and developer tools enhancements.

Security updates have been issued by AlmaLinux (freerdp, libxslt, python3.11, and python3.12), Debian (libpng1.6, lxd, netty, and python-tornado), Fedora (chunkah, cpp-httplib, firefox, freerdp, 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, gstreamer1-vaapi, insight, python-gstreamer1, python3.14, rust, rust-cargo-rpmstatus, rust-cargo-vendor-filterer, rust-resctl-bench, rust-scx_layered, rust-scx_rustland, rust-scx_rusty, and xen), Mageia (freeipmi, python-openssl, python-ply, ruby-rack, vim, and zlib), Oracle (firefox, freerdp, kernel, libpng, thunderbird, uek-kernel, and virt:ol and virt-devel:ol), Red Hat (golang), SUSE (bind, expat, fetchmail, ffmpeg-7, freerdp, gsl, incus, kernel, libjavamapscript, libjxl, libpng16-16, libpolkit-agent-1-0-127, net-snmp, net-tools, openexr, perl-XML-Parser, python-ldap, python-pyasn1, python-PyJWT, python311-requests, tailscale, thunderbird, tinyproxy, and ucode-intel), and Ubuntu (golang-golang-x-net-dev and ruby2.3, ruby2.5, ruby2.7, ruby3.0, ruby3.2, ruby3.3).

Discussion of a memory-management patch set intended to clean up a helper function for handling huge pages spiraled into something else entirely after it was posted on March 19. Memory-management maintainer Andrew Morton proposed making changes to the subsystem's review process, to require patch authors to respond to feedback from Sashiko, the recently released LLM-based kernel patch review system. Other sub-maintainers, particularly Lorenzo Stoakes, objected. The resulting discussion about how and when to adopt Sashiko is potentially relevant to many other parts of the kernel.

In early March, Dylan M. Taylor submitted a pull request to add a field to store a user's birth date in systemd's JSON user records. This was done to allow applications to store the date to facilitate compliance with age-attestation and -verification laws. It was to be expected that some members of the community would object; the actual response, however, has been shockingly hostile. Some of this has been fueled by a misinformation campaign that has targeted the systemd project and Taylor specifically, resulting in Taylor being doxxed and receiving death threats. Such behavior is not just problematic; it is also deeply misguided given the actual nature of the changes.

There is a blog post on sockpuppet.org arguing that we are not prepared for the upcoming flood of high-quality, LLM-generated vulnerability reports and exploits.

Now consider the poor open source developers who, for the last 18 months, have complained about a torrent of slop vulnerability reports. I'd had mixed sympathies, but the complaints were at least empirically correct. That could change real fast. The new models find real stuff. Forget the slop; will projects be able to keep up with a steady feed of verified, reproducible, reliably-exploitable sev:hi vulnerabilities? That's what's coming down the pipe.

Everything is up in the air. The industry is sold on memory-safe software, but the shift is slow going. We've bought time with sandboxing and attack surface restriction. How well will these countermeasures hold up? A 4 layer system of sandboxes, kernels, hypervisors, and IPC schemes are, to an agent, an iterated version of the same problem. Agents will generate full-chain exploits, and they will do so soon.

Meanwhile, no defense looks flimsier now than closed source code. Reversing was already mostly a speed-bump even for entry-level teams, who lift binaries into IR or decompile them all the way back to source. Agents can do this too, but they can also reason directly from assembly. If you want a problem better suited to LLMs than bug hunting, program translation is a good place to start.

Security updates have been issued by AlmaLinux (firefox, kernel, and kernel-rt), Debian (phpseclib and roundcube), Fedora (bind, bind-dyndb-ldap, dotnet8.0, dotnet9.0, firefox, freerdp, mingw-expat, musescore, nss, ntpd-rs, perl-YAML-Syck, php-phpseclib3, polkit, pyOpenSSL, python3.12, rust, rust-cargo-rpmstatus, rust-cargo-vendor-filterer, stgit, webkitgtk, and xen), SUSE (dovecot24, ImageMagick, jupyter-nbclassic, kernel, libjxl, libsuricata8_0_4, obs-service-recompress, obs-service-tar_scm, obs-service-set_version, openbao, perl-Crypt-URandom, plexus-utils, python-pyasn1, python-PyJWT, strongswan, traefik, traefik2, and webkit2gtk3), and Ubuntu (gst-plugins-base1.0, gst-plugins-good1.0, imagemagick, pillow, pyasn1, pyjwt, and roundcube).

SystemRescue 13.00 has been released. The SystemRescue distribution is a live boot system-rescue toolkit, based on Arch Linux, for repairing systems in the event of a crash. This release includes the 6.18.20 LTS kernel, updates bcachefs tools and kernel module to 1.37.3, and many upgraded packages. See the step-by-step guide for instructions on performing common operations such as recovering files, creating disk clones, and resetting lost passwords.

Version 4.0.0 of the Rspamd spam-filtering system has been released. Notable new features include HTML fuzzy phishing detection, support for up to eight flags with fuzzy hashes, and more. See the changelog for more on improvements, breaking changes, and bug fixes.