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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...

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...

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...

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...

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,...

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.

The kernel project merges dozens of drivers with every development cycle, and almost every one of those drivers is entirely uncontroversial. Occasionally, though, a driver submission raises wider questions, leading to lengthy discussion and, perhaps, opposition. That is currently the case with two separate drivers, both with ties to the networking subsystem. One of them is hung up on questions of whether (and how)...

Dirk Mueller has posted a lengthy analysis of the XZ backdoor on the openSUSE News site, with a focus on openSUSE's response. Debian, as well as the other affected distributions like openSUSE are carrying a significant amount of downstream-only patches to essential open-source projects, like in this case OpenSSH. With hindsight, that should be another Heartbleed-level learning for the work of the distributions. These...

Security updates have been issued by Debian (chromium), Fedora (rust, trafficserver, and upx), Mageia (postgresql-jdbc and x11-server, x11-server-xwayland, tigervnc), Red Hat (bind, bind9.16, gnutls, httpd:2.4, squid, unbound, and xorg-x11-server), SUSE (perl-Net-CIDR-Lite), and Ubuntu (apache2, maven-shared-utils, and nss).

The Earliest Virtual Deadline First (EEVDF) scheduler was merged as an option for the 6.6 kernel. It represents a major change to how CPU scheduling is done on Linux systems, but the EEVDF front has been relatively quiet since then. Now, though, scheduler developer Peter Zijlstra has returned from a long absence to post a patch series intended to finish the EEVDF work. Beyond...

Security updates have been issued by AlmaLinux (kernel, less, libreoffice, nodejs:18, nodejs:20, rear, thunderbird, and varnish), Debian (pillow), Fedora (dotnet7.0), SUSE (sngrep, texlive-specs-k, tomcat, tomcat10, and xorg-x11-server), and Ubuntu (nss, squid, and util-linux).

The Gentoo Linux project has announced that it is now an Associated Project of Software in the Public Interest (SPI), which will allow it to accept tax deductible donations in the US and reduce its "non-technical workload": The current Gentoo Foundation has bylaws restricting its behavior to that of a non-profit, is a recognized non-profit only in New Mexico, but a for-profit entity at...

Greg Kroah-Hartman has announced another round of stable kernel updates: 6.8.5, 6.6.26, 6.1.85, and 5.15.154 have all been released; each contains another set of important fixes, including the mitigations for the recently disclosed branch history injection hardware vulnerability.

A recent book by LWN guest author Lee Phillips provides a nice introduction to the Julia programming language. Practical Julia does more than that, however. As its subtitle ("A Hands-On Introduction for Scientific Minds") implies, the book focuses on bringing Julia to scientists, rather than programmers, which gives it something of a different feel from most other books of this sort.

On April 3 security researcher Bartek Nowotarski published the details of a new denial-of-service (DoS) attack, called a "continuation flood", against many HTTP/2-capable web servers. While the attack is not terribly complex, it affects many independent implementations of the HTTP/2 protocol, even though multiple similar vulnerabilities over the years have given implementers plenty of warning.

Security updates have been issued by Debian (gtkwave), Fedora (dotnet7.0, dotnet8.0, and python-pillow), Mageia (apache, gstreamer1.0, libreoffice, perl-Data-UUID, and xen), Oracle (kernel, kernel-container, and varnish), Red Hat (edk2, kernel, rear, and unbound), SUSE (apache2-mod_jk, gnutls, less, and xfig), and Ubuntu (bind9, 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-kvm, linux-oracle, linux-oracle-5.4, linux-raspi, linux-raspi-5.4, linux, linux-aws, linux-azure, linux-azure-6.5, linux-gcp, linux-gcp-6.5,...

The mainline kernel has just received a set of commits mitigating the latest x86 hardware vulnerability, known as "branch history injection". From this commit: Branch History Injection (BHI) attacks may allow a malicious application to influence indirect branch prediction in kernel by poisoning the branch history. eIBRS isolates indirect branch targets in ring0. The BHB can still influence the choice of indirect branch predictor...

On February 20, Linaro held the initial get-together for what is intended to be a regular Linux Kernel Forum for the Arm-focused kernel community. This gathering aims to convene approximately a few weeks prior to the merge window opening and prior to the release of the current kernel version under development. Topics covered in the first gathering include preparing 64-bit Arm kernels for low-end...

Version 3.3.0 of the OpenSSL SSL/TLS implementation has been released. Changes include a number of additions to its QUIC protocol support, some year-2038 improvements for 32-bit systems, and a lot of cryptographic features with descriptions like "Added a new EVP_DigestSqueeze() API. This allows SHAKE to squeeze multiple times with different output sizes." See the release notes for details.

There are many mechanisms for deferred work in the Linux kernel. One of them, workqueues, has seen increasing use as part of the move away from software interrupts. Alison Chaiken gave a talk at SCALE about how they compare to software interrupts, the new challenges they pose for system administrators, and what tools are available to kernel developers wishing to diagnose problems with workqueues...