Linux Community News

The New Stack looks at EU OS, an attempt to create a desktop system for the European public sector. EU OS is not a brand-new Linux distribution in the traditional sense. Instead, it is a proof-of-concept built atop Fedora’s immutable KDE Plasma spin (Kinoite). EU OS takes a layered approach to customization. The project’s vision is to provide a standard, adaptable Linux base that can be extended with national, regional or sector-specific customizations, making it suitable for a wide range of European public sector needs.

The final session in the memory-management track of the 2025 Linux Storage, Filesystem, Memory-Management, and BPF Summit was a brief, last-minute addition run by Kalesh Singh. The kernel’s readahead mechanism is generally good for performance; it ensures that data is present by the time an application gets around to asking for it. Sometimes, though, readahead can go a little too far.

Adding tracepoints to some kernel subsystems has been controversial—or disallowed—due to concerns about the user-space ABI that they might create. The virtual filesystem (VFS) layer has long been one of the subsystems that has not allowed any tracepoints, but that may be changing. At the 2025 Linux Storage, Filesystem, Memory Management, and BPF Summit (LSFMM+BPF), Ted Ts’o led a discussion about whether the ABI concerns are outweighed by the utility of tracepoints for the VFS.

Security updates have been issued by Debian (graphicsmagick and libapache2-mod-auth-openidc), Fedora (giflib, mod_auth_openidc, mysql8.0, perl, perl-Devel-Cover, perl-PAR-Packer, perl-String-Compare-ConstantTime, rust-openssl, rust-openssl-sys, trunk, and workrave), Mageia (chromium-browser-stable and rust), Oracle (java-1.8.0-openjdk, java-17-openjdk, java-21-openjdk, kernel, libreoffice, and webkit2gtk3), Red Hat (gvisor-tap-vsock), SUSE (containerd, docker, docker-stable, forgejo, GraphicsMagick, libmozjs-115-0, perl-32bit, poppler, subfinder, and thunderbird), and Ubuntu (erlang and ruby2.3, ruby2.5).

Version 25.04 (“Plucky Puffin”) of the Ubuntu Linux distribution has been released. This release includes Linux 6.14, GNOME 48, APT 3.0, and introduces a Arm64 desktop ISO to install Ubuntu Desktop on Arm64 systems. This is an interim release, with support through January 2026. See the release notes for a detailed list of new features and changes.

Version 14.5 of the Tor Browser has been released. Notable features in this release include the addition of Connection Assist for the Android version of the Tor Browser, and language support for Belarusian, Bulgarian, and Portuguese for all versions of the browser. Should Tor Browser fail to establish a direct connection to the Tor network, Connection Assist will offer to find and try bridges for you. But before this feature could be made available on Android, we had to embark on a multi-year effort to refactor our tor integration across each platform first. This project has now reached an important milestone, and we’re proud to announce the release of Connection Assist for Android today. See the full changelog for all changes in this release, and the issues page for known problems.

The kernel’s memory controller works within the control-group mechanism to enforce memory-usage limits on groups of processes. This component has often had performance problems, so there is continual interest in optimizing it. Shakeel Butt led a session during the memory-management track of the 2025 Linux Storage, Filesystem, Memory-Management, and BPF Summit to look at the current state of the memory controller and what can be done to reduce its overhead.

Security updates have been issued by Debian (chromium and libapache2-mod-auth-openidc), Oracle (expat, freetype, glibc, grub2, gvisor-tap-vsock, and kernel), Red Hat (grub2 and webkit2gtk3), and SUSE (apache2-mod_auth_openidc, cosign, gitoxide, govulncheck-vulndb, GraphicsMagick, haproxy, hauler, mozjs52, oci-cli, pam, perl-Data-Entropy, poppler, python-lxml-doc, python311-aiohttp, rekor, rubygem-rexml, and webkit2gtk3).

Inside this week’s LWN.net Weekly Edition: Front: APT 3.0; Fedora 42; Lots more LSFMM+BPF coverage. Briefs: CVE funding; Yelp vulnerability; Fedora 42; Manjaro 25.0; GCC 15; Pinta 3.0; Quotes; … Announcements: Newsletters, conferences, security updates, patches, and more.

Debian’s Advanced Package Tool (APT) is the suite of utilities that handle package management on Debian and Debian-derived operating systems. APT recently received a major upgrade to 3.0 just in time for inclusion in Debian 13 (“trixie”), which is planned for release sometime in 2025. The version bump is warranted; the latest APT has user-interface improvements, switches to Sequoia to verify package signatures, and includes solver3—a new solver that is designed to improve how it evaluates and resolves package dependencies.

GNOME contributor Michael Catanzaro has written a blog post about a noteworthy vulnerability in GNOME’s help browser, Yelp. I don’t normally blog about particular CVEs, but Yelp CVE-2025-3155 is noteworthy because it is quite severe, public for several weeks now, and not yet fixed upstream. In short, help files can read your filesystem and execute arbitrary JavaScript code, allowing an attacker to exfiltrate any files your Unix user has access to. The vulnerability was first reported on December 25, and it was made public on March 26 after the 90-day-disclosure deadline was reached. Patches have been proposed to fix the issue. The bug reporter has published a writeup demonstrating the attack. Catanzaro asks that Linux vendors “please consider applying the provided patches even though they have not yet been accepted upstream”.

Allowing directories to be modified in parallel was the topic of Jeff Layton’s filesystem-track session at the 2025 Linux Storage, Filesystem, Memory Management, and BPF Summit (LSFMM+BPF). There are certain use cases, including for the NFS and Lustre filesystems, as mentioned in a patch set referenced in the topic proposal, where contention in creating multiple files in a directory is causing noticeable performance problems. In some testing, Layton has found that the inode read-write semaphore (i_rwsem) for the directory is serializing operations; he wanted to discuss alternatives.

The BPF verifier is not magic; it cannot solve the halting problem. Therefore, it has to err on the side of assuming that a program will run too long if it cannot prove that the program will not. The ultimate check on the size of a BPF program is the one-million-instruction limit — the verifier will refuse to process more than one-million instructions, no matter what a BPF program does. Alexei Starovoitov gave a talk at the 2025 Linux Storage, Filesystem, Memory-Management, and BPF Summit about that limit, why correctly written BPF programs shouldn’t hit it, and how to make the user experience of large BPF programs better in the future.

Sergiu Gatlan reports that the US government has extended funding for the Common Vulnerabilities and Exposures (CVE) program, following yesterday’s reports that funding would run out as of April 16. “The CVE Program is invaluable to cyber community and a priority of CISA,” the U.S. cybersecurity agency told BleepingComputer. “Last night, CISA executed the option period on the contract to ensure there will be no lapse in critical CVE services. We appreciate our partners’ and stakeholders’ patience.” The article also mentions the launch of a CVE Foundation, to transition the CVE program to a dedicated foundation and eliminate “a single point of failure in the vulnerability management ecosystem”, as well as a European vulnerability database (EUVD) backed by the European Union Agency for Cybersecurity (ENISA). Details on these initiatives are scant at the moment, and it is unclear whether restoration of funding will have any impact on these efforts.

As a system runs, its memory becomes fragmented; it does not take long before the allocation of large, physically contiguous memory ranges becomes difficult or impossible. The contiguous memory allocator (CMA) is a kernel subsystem that attempts to address this problem, but it has never worked as well as some would like. Two sessions in the memory-management track at the 2025 Linux Storage, Filesystem, Memory-Management, and BPF Summit looked at how CMA can be improved; the first looked at providing guaranteed allocations, while the second addressed some inefficiencies in CMA.