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Version 29.3 of the Emacs editor has been released:

Emacs 29.3 is an emergency bugfix release; it includes no new features except a small number of changes intended to resolve security vulnerabilities uncovered in Emacs 29.2.

Those vulnerabilities mostly have to do with executing untrusted Lisp code; see the NEWS file for a bit more information.

The 6.9-rc1 kernel prepatch is out for testing. Linus Torvalds described some rather large updates to the core kernel code that are coming for 6.9: The timer subsystem had a fairly big rewrite, to have per-cpu timer wheels to improve performance of timers, which can be a big deal particularly for networking. The other fairly notable core update is to the workqueue subsystem, where one notable addition is for BH workqueue support. That's notable mainly because it means we finally have a way away from tasklets. The tasklet interface has basically been deprecated for a long while, but we've never really had any good alternatives (with threaded interrupt handlers being one suggested use-case, but not realistic in many cases).

Security updates have been issued by Debian (firefox-esr, pillow, and thunderbird), Fedora (apptainer, chromium, ovn, and webkitgtk), Mageia (apache-mod_auth_openidc, ffmpeg, fontforge, libuv, and nodejs-tough-cookie), Oracle (kernel, libreoffice, postgresql-jdbc, ruby:3.1, squid, and squid:4), Red Hat (go-toolset:rhel8 and libreoffice), SUSE (firefox, jbcrypt, trilead-ssh2, jsch-agent-proxy, kernel, tiff, and zziplib), and Ubuntu (linux-aws and openssl1.0).

While a programming error in the kernel may be subject to direct exploitation, usually a more roundabout approach is required to take advantage of a security bug. One popular approach for those wishing to take advantage of vulnerabilities is heap spraying, and it has often been employed to compromise the kernel. In the future, though, heap-spraying attacks may be a bit harder to pull off, thanks to the "dedicated bucket allocator" proposed by Kees Cook.

Security updates have been issued by Debian (pdns-recursor and php-dompdf-svg-lib), Fedora (grub2, libreswan, rubygem-yard, and thunderbird), Mageia (libtiff and python-scipy), Red Hat (golang, nodejs, and nodejs:16), Slackware (python3), and Ubuntu (linux, linux-azure, linux-azure-5.15, linux-azure-fde, linux-azure-fde-5.15, linux-gcp, linux-gcp-5.15, linux-gke, linux-gkeop, linux-gkeop-5.15, linux-hwe-5.15, linux-ibm, linux-ibm-5.15, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-nvidia, linux, linux-azure, linux-gcp, linux-gcp-6.5, linux-hwe-6.5, linux-lowlatency, linux-lowlatency-hwe-6.5, linux-oem-6.5, linux-oracle, linux-oracle-6.5, linux-raspi, linux-starfive, linux-starfive-6.5, linux-aws, linux-aws-5.15, linux-aws, linux-aws-5.4, linux-gcp-5.4, linux-raspi, linux-raspi-5.4, linux-xilinx-zynqmp, linux-gcp, linux-gcp-4.15, linux-kvm, linux-laptop, linux-oem-6.1, and linux-raspi).

Version 1.77.0 of the Rust language has been released. Changes include support for NUL-terminated C-string literals, the ability for async functions to call themselves recursively, the stabilization of the offset_of!() macro, and more.

Verson 5.39.9 of the Perl language has been released. Changes this time include a new "medium-precedence" logical exclusive-or operator, a number of updated modules, and more; see this page for details.

The Redis in-memory database system has had its license changed to either the Redis Source Available License or the Server Side Public License (covered here in 2018); neither license qualifies as free software.

Under the new license, cloud service providers hosting Redis offerings will no longer be permitted to use the source code of Redis free of charge. For example, cloud service providers will be able to deliver Redis 7.4 only after agreeing to licensing terms with Redis, the maintainers of the Redis code.

Distributors like Fedora are already looking at removing Redis as a consequence. (Thanks to Emmanuel Seyman).

Danilo Krummrich has announced the existence of the "Nova" project within Red Hat.

We just started to work on Nova, a Rust-based GSP-only driver for Nvidia GPUs. Nova, in the long term, is intended to serve as the successor of Nouveau for GSP-firmware-based GPUs.

With Nova we see the chance to significantly decrease the complexity of the driver compared to Nouveau for mainly two reasons. First, Nouveau's historic architecture, especially around nvif/nvkm, is rather complicated and inflexible and requires major rework to solve certain problems (such as locking hierarchy in VMM / MMU code for VM_BIND currently being solved with a workaround) and second, with a GSP-only driver there is no need to maintain compatibility with pre-GSP code.

Besides that, we also want to take the chance to contribute to the Rust efforts in the kernel and benefit from from more memory safety offered by the Rust programming language.

Given that the effort has just begun, it will be a while before this driver shows up in a distribution release.

The LWN.net Weekly Edition for March 21, 2024 is available.

Version 46 of the GNOME desktop has been released. "GNOME 46 is code-named 'Kathmandu', in recognition of the amazing work done by the organizers of GNOME.Asia 2023." Significant changes include a new global search feature, enhancements to the Files app, improved remote login support, and more.

Cockpit is an interesting project for web-based Linux administration that has received relatively little attention over the years. Part of that may be due to the project's strategy of minor releases roughly every two weeks, rather than larger releases with many new features. While the strategy has done little to garner headlines, it has delivered a useful and extensible tool to observe, manage, and troubleshoot Linux servers.

The Python project has announced three security releases, 3.10.14, 3.9.19, and 3.8.19. In addition to the security fixes, these releases are notable for two reasons; they are the first to make use of GitHub Actions to perform public builds instead of building artifacts "on a local computer of one of the release managers", and the first since Python became a CVE Numbering Authority (CNA).

Python release team member Łukasz Langa said that being a CNA means Python is able to "ensure the quality of the vulnerability reports is high, and that the severity estimates are accurate." It also allows Python to coordinate CVE announcements with the patched versions of Python, as it has with two CVEs addressed in these releases. CVE-2023-6597 describes a flaw in CPython's zipfile module that made it vulnerable to a zip-bomb exploit. CVE-2024-0450 is an issue with Python's tempfile.TemporaryDirectory class which could be exploited to modify permissions of files referenced by symbolic links. Users of affected versions should upgrade soon.

Security updates have been issued by Debian (fontforge and imagemagick), Fedora (firefox), Mageia (cherrytree, python-django, qpdf, and sqlite3), Red Hat (bind, cups, emacs, fwupd, gmp, kernel, libreoffice, libX11, nodejs, opencryptoki, postgresql-jdbc, postgresql:10, postgresql:13, and ruby:3.1), Slackware (gnutls and mozilla), and Ubuntu (firefox, linux, linux-bluefield, linux-gcp, linux-gkeop, linux-hwe-5.4, linux-ibm, linux-ibm-5.4, linux-iot, linux-kvm, linux-oracle, linux-oracle-5.4, linux-aws, linux-aws-5.4, linux-aws, linux-aws-6.5, and linux-oracle, linux-oracle-5.15).

There are a number of different language-enhancement ideas that crop up with some regularity in the Python community; many of them have been debated and shot down multiple times over the years. When one inevitably arises anew, it can sometimes be difficult to tamp it down, even if it is unlikely that the idea will go any further than the last N times it cropped up. A recent discussion about "real" anonymous functions follows a somewhat predictable path, but there are still reasons to participate in vetting these "new" ideas, despite the tiresome, repetitive nature of the exercise—examples of recurring feature ideas that were eventually adopted definitely exist.

Version 124.0 of the Firefox browser is out. Changes include support for "caret browsing mode" in the PDF viewer and the ability to control the sorting of tabs in the Firefox View screen.

Security updates have been issued by Debian (cacti, postgresql-11, and zfs-linux), Fedora (freeimage, mingw-expat, and mingw-freeimage), Mageia (apache-mod_security-crs, expat, and multipath-tools), Oracle (.NET 7.0 and kernel), Red Hat (kernel, kernel-rt, and kpatch-patch), and Ubuntu (bash, kernel, linux, linux-aws, linux-hwe, linux-kvm, linux-oracle, linux, linux-aws, linux-kvm, linux-lts-xenial, and vim).

Man Yue Mo explains how to compromise a Pixel 8 phone even when the Arm memory-tagging extension is in use, by taking advantage of the Mali GPU.

So, by using the GPU to access physical addresses directly, I'm able to completely bypass the protection that MTE offers. Ultimately, there is no memory safe code in the code that manages memory accesses. At some point, physical addresses will have to be used directly to access memory.

Kernel developers have long been told that any attempt to allocate memory might fail, so their code must be prepared for memory to be unavailable. Informally, though, the kernel's memory-management subsystem implements a policy whereby requests below a certain size will not fail (in process context, at least), regardless of how tight memory may be. A recent discussion on the linux-mm list has looked at the idea of making the "too small to fail" rule a policy that developers can rely on.

Security updates have been issued by Debian (curl, spip, and unadf), Fedora (chromium, iwd, opensc, openvswitch, python3.6, shim, shim-unsigned-aarch64, and shim-unsigned-x64), Mageia (batik, imagemagick, irssi, jackson-databind, jupyter-notebook, ncurses, and yajl), Oracle (.NET 7.0, .NET 8.0, and dnsmasq), Red Hat (postgresql:10), SUSE (chromium, kernel, openvswitch, python-rpyc, and tiff), and Ubuntu (openjdk-8).