Video playback is undeniably one of the most important features in modern consumer devices. Yet, surprisingly, users are by and large unaware of the intricate engineering involved in the compression and decompression of video data, with codecs being left to find a delicate balance between image quality, bandwidth, and power consumption. In response to constant performance pressure, video codecs have become complex and hardware implementations are now common, but programming these devices is becoming increasingly difficult and fraught with opportunities for exploitation. I hope to convey how Rust can help fix this problem.

At the CPU level, a memory model describes, among other things, the amount of freedom the processor has to reorder memory operations. If low-level code does not take the memory model into account, unpleasant surprises are likely to follow. Naturally, different CPUs offer different memory models, complicating the portability of certain types of concurrent software. To make life easier, some Arm CPUs offer the ability to emulate the x86 memory model, but efforts to make that feature available in the kernel are running into opposition.

Security updates have been issued by Debian (knot-resolver, pdns-recursor, and putty), Fedora (xen), Mageia (editorconfig-core-c, glibc, mbedtls, webkit2, and wireshark), Oracle (buildah), Red Hat (buildah and yajl), Slackware (libarchive), SUSE (dcmtk, openCryptoki, php7, php74, php8, python-gunicorn, python-idna, qemu, and thunderbird), and Ubuntu (cryptojs, freerdp2, nghttp2, and zabbix).

On April 11, Brandt Bucher posted PEP 744 ("JIT Compilation"), which summarizes the current state of Python's new copy-and-patch just-in-time (JIT) compiler. The JIT is currently experimental, but the PEP proposes some criteria for the circumstances under which it should become a non-experimental part of Python. The discussion of the PEP hasn't reached a conclusion, but several members of the community have already raised questions about how the JIT would fit into future iterations of the Python language.

Version 24.04 LTS of the Ubuntu distribution is out.

This release continues Ubuntu's proud tradition of integrating the latest and greatest open source technologies into a high-quality, easy-to-use Linux distribution. The team has been hard at work through this cycle, together with the community and our partners, to introduce new features and fix bugs.

The list of changes and enhancements is long; click below for some details. More information can be found in the release notes; see also this page for a summary of security-related changes.

Linux, famously, appears in a wide range of systems. While servers and large data centers get a lot of the attention, and this year will always be the year of the Linux desktop, there is also a great deal of Linux to be found in realtime and embedded applications. Two talks held in the realtime and embedded tracks of the 2024 Open Source Summit North America provided listeners with an update on how Linux is doing in those areas. Work on realtime Linux appears to be nearing completion, while the embedded community is still pushing forward at full speed.

Security updates have been issued by Fedora (curl, filezilla, flatpak, kubernetes, libfilezilla, thunderbird, and xen), Oracle (go-toolset:ol8, kernel, libreswan, shim, and tigervnc), Red Hat (buildah, gnutls, libreswan, tigervnc, and unbound), SUSE (cockpit-wicked, nrpe, and python-idna), and Ubuntu (dnsmasq, freerdp2, linux-azure-6.5, and thunderbird).

The LWN.net Weekly Edition for April 25, 2024 is available.

BleepingComputer reported on April 20 that some malware was being distributed via GitHub. Uploading files as part of a comment gives them a URL that appears to be associated with a repository, even if the comment is never posted.

A GitHub flaw, or possibly a design decision, is being abused by threat actors to distribute malware using URLs associated with Microsoft repositories, making the files appear trustworthy.

While most of the malware activity has been based around the Microsoft GitHub URLs, this "flaw" could be abused with any public repository on GitHub, allowing threat actors to create very convincing lures.

On April 23, Mozilla announced that Firefox's crash reporter has been rewritten in Rust, allowing the project to address a backlog of issues.

Even though it is important to properly handle main process crashes, the crash reporter hasn't received significant development in a while (aside from development to ensure that crash reports and telemetry continue to reliably be delivered)! It has long been stuck in a local maximum of "good enough" and "scary to maintain": it features 3 individual GUI implementations (for Windows, GTK+ for Linux, and macOS), glue code abstracting a few things (mostly in C++, and Objective-C for macOS), a binary blob produced by obsoleted Apple development tools, and no test suite. Because of this, there is a backlog of features and improvements which haven't been acted on.

Version 9.0 of the QEMU emulator has been released. "This release contains 2700+ commits from 220 authors." The list of improvements is long; see the announcement and the changelog for details.

For several years, contributors to the Rust project have been working to improve support for asynchronous code. The benefits of these efforts are not confined to asynchronous code, however. Members of the Rust community have been working toward adding explicit existential types to Rust since 2017. Existential types are not a common feature of programming languages (something the RFC acknowledges), so the motivation for their inclusion might be somewhat obscure.

Security updates have been issued by Fedora (abseil-cpp, chromium, filezilla, libfilezilla, and xorg-x11-server-Xwayland), Oracle (firefox, gnutls, golang, java-1.8.0-openjdk, java-11-openjdk, java-17-openjdk, java-21-openjdk, kernel, libreswan, mod_http2, owO: thunderbird, and thunderbird), Red Hat (container-tools:rhel8, gnutls, grub2, kernel, kernel-rt, less, linux-firmware, opencryptoki, pcs, postgresql-jdbc, and thunderbird), Slackware (ruby), SUSE (kubernetes1.23, kubernetes1.24, and opensc), and Ubuntu (firefox, linux-azure, linux-lowlatency, linux-nvidia, and ruby-sanitize).

Forum: Meeting μηνός Δημοσιεύτηκε Από: john70 Χρόνος Δημοσίευσης: 23/04/2024 στις 20:12

The long-running effort to complete the work on stacking (or composing) the Linux security modules (LSMs) recently encountered a barrier—in the form of a "suggestion" to discontinue it from Linus Torvalds. His complaint revolved around the indirect function calls that are used to implement LSMs, but he also did not think much of the effort to switch away from those calls. While it does not appear that a major course-change is in store for LSMs, it is clear that Torvalds is not happy with the direction of that subsystem.

The Fedora 40 distribution has been released. See the "what's new" pages for Fedora Workstation and Fedora KDE to learn more about the desktop spins, along with this LWN article, for more information.

The Rust programming language, it is hoped, will bring a new level of safety to the Linux kernel. At the moment, though, there are still a number of impediments to getting useful Rust code into the kernel. In the Embedded Open Source Summit track of the Open Source Summit North America, Fabien Parent provided an overview of his work aimed at improving the infrastructure needed to write the device drivers needed by embedded systems in Rust; there is still some work to be done.

Security updates have been issued by Debian (glibc and samba), Fedora (chromium, cjson, mingw-python-idna, and pgadmin4), Mageia (kernel, kmod-xtables-addons, kmod-virtualbox, kernel-linus, and perl-Clipboard), Red Hat (go-toolset:rhel8, golang, java-11-openjdk, kpatch-patch, and shim), Slackware (freerdp), SUSE (apache-commons-configuration, glibc, jasper, polkit, and qemu), and Ubuntu (google-guest-agent, google-osconfig-agent, linux-lowlatency-hwe-6.5, pillow, and squid).

The Open Home Foundation has announced its existence as a home and support resource for free home-automation projects.

We created the Open Home Foundation to fight for the fundamental principles of privacy, choice, and sustainability for smart homes. And every person who lives in one.

Ahead of today, we've transferred over 240 projects, standards, drivers, and libraries—Home Assistant, ESPHome, Zigpy, Piper, Improv Wi-Fi, Wyoming, and so many more—to the Open Home Foundation. This is all about looking into the future. We've done this to create a bulwark against surveillance capitalism, the risk of buyout, and open-source projects becoming abandonware. To an extent, this protection extends even against our future selves—so that smart home users can continue to benefit for years, if not decades. No matter what comes.

The Debian project leader election results are in and Andreas Tille has been elected. In a fairly competitive vote, Tille beat Sruthi Chandran to fill the position for the coming year. We looked at the election and the candidates a few weeks back.

One of the mainstays of the the Linux Foundation's Open Source Summit is the "fireside chat" (sans fire) between Linus Torvalds and Dirk Hohndel to discuss open source and Linux kernel topics of the day. On April 17, at Open Source Summit North America (OSSNA) in Seattle, Washington, they held with tradition and discussed a range of topics including proper whitespace parsing, security, and the current AI craze.

Peter Hutterer announces udev-hid-bpf, a tool to facilitate the loading of BPF programs that make human-input devices work correctly.

eBPF was originally written for network packet filters but as of kernel v6.3 and thanks to Benjamin, we have BPF in the HID subsystem. HID actually lends itself really well to BPF because, well, we have a byte array and to fix our devices we need to do complicated things like "toggle that bit to zero" or "swap those two values".

See this article for more information on the BPF-HID mechanism.

Security updates have been issued by AlmaLinux (firefox and java-1.8.0-openjdk), Debian (chromium, flatpak, guix, openjdk-11, openjdk-17, thunderbird, and tomcat9), Fedora (chromium, firefox, glibc, nghttp2, nodejs18, python-aiohttp, python-django3, python-pip, and uxplay), Mageia (putty & filezilla), Red Hat (Firefox, firefox, java-1.8.0-openjdk, java-21-openjdk, nodejs:18, shim, and thunderbird), Slackware (freerdp), SUSE (apache-commons-configuration2, nodejs14, perl-CryptX, putty, shim, and wireshark), and Ubuntu (linux, linux-aws, linux-aws-5.15, 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-intel-iotg, linux-intel-iotg-5.15, linux-kvm, linux-lowlatency-hwe-5.15, linux-oracle, linux-oracle-5.15, linux-raspi, linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-bluefield, linux-gcp, linux-gcp-5.4, linux-gkeop, linux-hwe-5.4, linux-ibm, linux-ibm-5.4, linux-iot, linux-kvm, linux-oracle, linux-oracle-5.4, linux-raspi, linux-raspi-5.4, linux-xilinx-zynqmp, linux, linux-aws, linux-aws-6.5, linux-azure, linux-gcp, linux-gcp-6.5, linux-hwe-6.5, linux-laptop, linux-lowlatency, linux-nvidia-6.5, linux-oem-6.5, linux-oracle, linux-oracle-6.5, linux-raspi, linux-starfive, linux-starfive-6.5, linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-gcp, linux-gcp-4.15, linux-hwe, linux-kvm, linux-oracle, linux, linux-aws, linux-kvm, linux-lts-xenial, lxd, percona-xtrabackup, and pillow).

Linus has released 6.9-rc5 for testing.

But if you ignore those oddities, it all looks pretty normal and things appear fairly calm. Which is just as well, since the first part of the week I was on a quick trip to Seattle, and the second part of the week I've been doing a passable imitation of the Fontana di Trevi, except my medium is mucus.

Gregory Price recently posted a patch set that adds support for weighted memory interleaving — allowing a process's memory to be distributed between non-uniform memory access (NUMA) nodes in a more controlled way. According to his performance measurements, the patch set could provide a significant improvement for computers with network-attached memory. The patch set also introduces new system calls and paves the way for future extensions intended to give processes more control over their own memory.

Security updates have been issued by AlmaLinux (gnutls, java-17-openjdk, mod_http2, and squid), Debian (firefox-esr), Fedora (editorconfig, perl-Clipboard, php, rust, and wordpress), Mageia (less, libreswan, puppet, and x11-server, x11-server-xwayland, and tigervnc), Slackware (aaa_glibc), and SUSE (firefox, graphviz, kernel, nodejs12, pgadmin4, tomcat, and wireshark).

Gentoo Council member Michał Górny posted an RFC to the gentoo-dev mailing list in late February about banning "'AI'-backed (LLM/GPT/whatever) contributions" to the Gentoo Linux project. Górny wrote that the spread of the "AI bubble" indicated a need for Gentoo to formally take a stand on AI tools. After a lengthy discussion, the Gentoo Council voted unanimously this week to adopt his proposal and ban contributions generated with AI/ML tools.

Kernel developers, like conscientious developers for many projects, will often include checks in the code for conditions that are never expected to occur, but which would indicate a serious problem should that expectation turn out to be incorrect. For years, developers have been encouraged (to put it politely) to avoid using assertions that crash the machine for such conditions unless there is truly no alternative. Increasingly, though, use of the kernel's WARN_ON() family of macros, which developers were told to use instead, is also being discouraged.

Security updates have been issued by Debian (firefox-esr, jetty9, libdatetime-timezone-perl, tomcat10, and tzdata), Fedora (cockpit, filezilla, and libfilezilla), Red Hat (firefox, gnutls, java-1.8.0-openjdk, java-17-openjdk, kernel, kernel-rt, less, mod_http2, nodejs:18, rhc-worker-script, and shim), Slackware (mozilla), SUSE (kernel), and Ubuntu (apache2, glibc, and linux-xilinx-zynqmp).

The LWN.net Weekly Edition for April 18, 2024 is available.

Forum: Meeting μηνός Δημοσιεύτηκε Από: john70 Χρόνος Δημοσίευσης: 17/04/2024 στις 21:43

Managing to-do lists is something of a universal necessity. While some people handle them mentally or on paper, others resort to a web-based tool or a mobile application. For those preferring the command line, the MIT-licensed Taskwarrior offers a flexible solution with a healthy community and lots of extensions.

The 6.8.7, 6.6.28, 6.1.87, and 5.15.156 stable kernel updates have all been released.

Security updates have been issued by Debian (apache2 and cockpit), Fedora (firefox, kernel, mbedtls, python-cbor2, wireshark, and yyjson), Mageia (nghttp2), Red Hat (kernel, kernel-rt, opencryptoki, pcs, shim, squid, and squid:4), Slackware (firefox), SUSE (emacs, firefox, and kernel), and Ubuntu (linux-aws, linux-aws-5.15, linux-aws-6.5, linux-raspi, and linux-iot).

The recent XZ backdoor has sparked a lot of discussion about how the open-source community links and packages software. One possible security improvement being discussed is changing how projects like systemd link to dynamic libraries that are only used for optional functionality: using dlopen() to load those libraries only when required. This could shrink the attack surface exposed by dependencies, but the approach is not without downsides — most prominently, it makes discovering which dynamic libraries a program depends on harder. On April 11, Lennart Poettering proposed one way to eliminate that problem in a systemd RFC on GitHub.

Fedora 40 Beta was released on March 26, and the final release is nearing completion. So far, the release is coming together nicely with major updates for GNOME, KDE Plasma, and the usual cavalcade of smaller updates and enhancements. As part of the release, the project also scuttled Delta RPMs and OpenSSL 1.1.

Version 0.81 of the PuTTY SSH client is out with a fix for CVE-2024-31497; some users will want to update and generate new keys:

PuTTY 0.81, released today, fixes a critical vulnerability CVE-2024-31497 in the use of 521-bit ECDSA keys (ecdsa-sha2-nistp521). If you have used a 521-bit ECDSA private key with any previous version of PuTTY, consider the private key compromised: remove the public key from authorized_keys files, and generate a new key pair.

However, this only affects that one algorithm and key size. No other size of ECDSA key is affected, and no other key type is affected.

Security updates have been issued by Debian (php7.4 and php8.2), Fedora (c-ares), Mageia (python-pillow and upx), Oracle (bind and dhcp, bind9.16, httpd:2.4/mod_http2, kernel, rear, and unbound), SUSE (eclipse, maven-surefire, tycho, emacs, kubevirt, virt-api-container, virt-controller-container, virt-exportproxy-container, virt-exportserver-container, virt-handler-container, virt-launcher-container, virt-libguestfs-t, nodejs16, nodejs18, nodejs20, texlive, vim, webkit2gtk3, and xen), and Ubuntu (gnutls28, klibc, libvirt, nodejs, and webkit2gtk).

The Open Source Security Foundation and the OpenJS Foundation have jointly posted a warning about XZ-like social-engineering attacks after OpenJS was seemingly targeted.

The OpenJS Foundation Cross Project Council received a suspicious series of emails with similar messages, bearing different names and overlapping GitHub-associated emails. These emails implored OpenJS to take action to update one of its popular JavaScript projects to "address any critical vulnerabilities," yet cited no specifics. The email author(s) wanted OpenJS to designate them as a new maintainer of the project despite having little prior involvement.

Kumar Kartikeya Dwivedi has been working to add support for exceptions to BPF since mid-2023. In July, Dwivedi posted the first patch set in this effort, which adds support for basic stack unwinding. In February 2024, he posted the second patch set aimed at letting the kernel release resources held by the BPF program when an exception occurs. This makes exceptions usable in many more contexts.

Security updates have been issued by AlmaLinux (bind, bind and dhcp, bind9.16, gnutls, httpd:2.4/mod_http2, squid:4, and unbound), Debian (kernel, trafficserver, and xorg-server), Fedora (chromium, kernel, libopenmpt, and rust-h2), Mageia (apache-mod_jk, golang, indent, openssl, perl-HTTP-Body, php, rear, ruby-rack, squid, varnish, and xfig), Oracle (bind, squid, unbound, and X.Org server), Red Hat (bind and dhcp and unbound), Slackware (less and php), SUSE (gnutls, python-Pillow, webkit2gtk3, xen, xorg-x11-server, and xwayland), and Ubuntu (yard).

The 6.9-rc4 kernel prepatch is out for testing. "Nothing particularly unusual going on this week - some new hw mitigations may stand out, but after a decade of this I can't really call it 'unusual' any more, can I?"

The 6.8.6, 6.6.27, 6.1.86, 5.15.155, 5.10.215, 5.4.274, and 4.19.312 stable kernel updates have all been released; each contains a relatively large number of important fixes.