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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).

Cranelift is an Apache-2.0-licensed code-generation backend being developed as part of the Wasmtime runtime for WebAssembly. In October 2023, the Rust project made Cranelift available as an optional component in its nightly toolchain. Users can now use Cranelift as the code-generation backend for debug builds of projects written in Rust, making it an opportune time to look at what makes Cranelift different. Cranelift is designed to compete with existing compilers by generating code more quickly than they can, thanks to a stripped-down design that prioritizes only the most important optimizations.

Zach Mitchell has announced the 1.0 release of Flox, a tool that lets its users install packages from nixpkgs inside portable virtual environments, and share those virtual environments with others as an alternative to Docker-style containers. Flox is based on Nix but allows users to skip learning how to work with the Nix language:

With Flox we're providing a substantially better user experience. We provide the suite of package manager functionality with install, uninstall, etc, but we also provide an entire new suite of functionality with the ability to share environments via flox push, flox pull, and flox activate --remote.

Flox is GPLv2-licensed, and releases are available as RPMs and Debian packages for x86_64 and arm64 systems.

Sasha Levin has announced the release of the 6.8.1, 6.7.10, 6.6.22, 6.1.82, 5.15.152, 5.10.213, 5.4.272, and 4.19.310 stable kernels. As always, they contain important fixes throughout the tree. Users of those kernels should upgrade.

Security updates have been issued by Debian (composer and node-xml2js), Fedora (baresip), Mageia (fonttools, libgit2, mplayer, open-vm-tools, and packages), Red Hat (dnsmasq, gimp:2.8, and kernel-rt), and SUSE (389-ds, gdb, kernel, python-Django, python3, python36-pip, spectre-meltdown-checker, sudo, and thunderbird).

As of this writing, just over 4,900 non-merge changesets have been pulled into the mainline for the 6.9 release. This work includes the usual array of changes all over the kernel tree; read on for a summary of the most significant work merged during the first part of the 6.9 merge window.

Security updates have been issued by Debian (chromium and openvswitch), Fedora (chromium, python-multipart, thunderbird, and xen), Mageia (java-17-openjdk and screen), Red Hat (.NET 7.0, .NET 8.0, kernel-rt, kpatch-patch, postgresql:13, and postgresql:15), Slackware (expat), SUSE (glibc, python-Django, python-Django1, sudo, and vim), and Ubuntu (expat, linux-ibm, linux-ibm-5.4, linux-oracle, linux-oracle-5.4, linux-lowlatency, linux-raspi, python-cryptography, texlive-bin, and xorg-server).

The LWN.net Weekly Edition for March 14, 2024 is available.

Kaitlyn Abdo of Fedora's AI/ML SIG opened an issue with the Fedora Engineering Steering Committee (FESCo) recently that carried a few tricky questions about packaging machine-learning (ML) models for Fedora. Specifically, the SIG is looking for guidance on whether pre-trained weights for PyTorch constitute code or content. And, if the models are released under a license approved by the Open Source Initiative (OSI), does it matter what data the models were trained on? The issue was quickly tossed over to Fedora's legal mailing list and sparked an interesting discussion about how to handle these items, and a temporary path forward.

Security updates have been issued by Fedora (edk2, freeipa, kernel, and liblas), Oracle (kernel), Red Hat (docker, edk2, kernel, kernel-rt, and kpatch-patch), SUSE (axis, fontforge, gnutls, java-1_8_0-openjdk, kernel, python3, sudo, and zabbix), and Ubuntu (dotnet7, dotnet8, libgoogle-gson-java, openssl, and ovn).

The pidfd abstraction is a Linux-specific way of referring to processes that avoids the race conditions inherent in Unix process ID numbers. Since a pidfd is a file descriptor, it needs a filesystem to implement the usual operations performed on files. As the use of pidfds has grown, they have stressed the limits of the simple filesystem that was created for them. Christian Brauner has created a new filesystem for pidfds that seems likely to debut in the 6.9 kernel, but it ran into a little bump along the way, demonstrating that things you cannot see can still hurt you.

The mainline kernel has just received a set of commits addressing the "register file data sampling" hardware vulnerability.

RFDS may allow a malicious actor to infer data values previously used in floating point registers, vector registers, or integer registers. RFDS does not provide the ability to choose which data is inferred

Only Atom cores are affected, but those cores can be found inside a number of processors. See this documentation commit for more information.

Herb Sutter, chair of the ISO C++ standards committee, writes about the current problems with writing secure C++, and his personal opinion on next steps to address this while maintaining backward compatibility.

If there were 90-98% fewer C++ type/bounds/initialization/lifetime vulnerabilities we wouldn't be having this discussion. All languages have CVEs, C++ just has more (and C still more); so far in 2024, Rust has 6 CVEs, and C and C++ combined have 61 CVEs. So zero isn't the goal; something like a 90% reduction is necessary, and a 98% reduction is sufficient, to achieve security parity with the levels of language safety provided by MSLs [memory-safe languages]… and has the strong benefit that I believe it can be achieved with perfect backward link compatibility (i.e., without changing C++'s object model, and its lifetime model which does not depend on universal tracing garbage collection and is not limited to tree-based data structures) which is essential to our being able to adopt the improvements in existing C++ projects as easily as we can adopt other new editions of C++. — After that, we can pursue additional improvements to other buckets, such as thread safety and overflow safety.

Serialization is the process of transforming Python objects into a sequence of bytes which can be used to recreate a copy of the object later — or on another machine. pickle is Python's native serialization module. It can store complex Python objects, making it an appealing prospect for moving data without having to write custom serialization code. For example, pickle is an integral component of several file formats used for machine learning. However, using pickle to deserialize untrusted files is a major security risk, because doing so can invoke arbitrary Python functions. Consequently, the machine-learning community is working to address the security issues caused by widespread use of pickle.