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Cisco has some unusual challenges when it comes to deploying security patches across the company's many devices running custom kernels. John Fastabend spoke about his work preventing exploits with BPF at the 2026 Linux Storage, Filesystem, Memory-Management, and BPF Summit. The technique could substantially reduce the time necessary to respond to kernel vulnerabilities, but it will not be fully effective unless more hooks are added to the kernel.

Debian has announced the final normal update for Debian 12 ("bookworm"). Long-term-support updates will continue until 2028. As may be expected from a stable version, the update is mostly limited to security fixes. Still, it may be time for Debian users to look into upgrading to a more recent version. Conveniently, Debian 13 ("trixie") also received an update this weekend, with many of the same security fixes.

Security updates have been issued by Debian (chromium, libxfont, mesa, opam, and wireless-regdb), Fedora (acl, attr, chromium, cjson, composer, docker-compose, jfrog-cli, librabbitmq, libssh2, libXfont2, log4cxx, OpenImageIO, openssh, p11-kit, perl-Crypt-DSA, perl-HTML-Gumbo, prometheus, python-dulwich, python-idna, python-pillow, python-tornado, sssd, tmux, upower, webkitgtk, xorg-x11-server, and xorg-x11-server-Xwayland), Mageia (libarchive and vim), Oracle (389-ds:1.4, buildah, cups, edk2, freerdp, golang, grafana, gstreamer1-plugins-bad-free, gstreamer1-plugins-good, gstreamer1-plugins-ugly-free, kernel, libexif, libsolv, libtasn1, libxml2, nginx:1.24, nginx:1.26, nodejs:22, nodejs:24, oci-seccomp-bpf-hook, podman, postgresql:18, python-urllib3, tigervnc, tomcat, unbound, and xorg-x11-server), Slackware (p11-kit), and SUSE (agama, dash, dracut, flannel, go1.26, gsasl, gstreamer-plugins-good, ImageMagick, imagemagick, kernel, krb5, krb5, krb5-mini, libIex-3_4-33, libmbedtls23, libxfont2, nasm, nghttp2, perl-CGI-Session, perl-dbi, perl-List-SomeUtils-XS, python-pillow, python-social-auth-app-django, python-urllib3, python313-Django4, python313-Django6, python313-pytest-html, python313-sqlparse, python313-websockets, rclone, rust-keylime, rustup, sccache, spectre-meltdown-checker, sssd, terraform-provider-aws, terraform-provider-azurerm, terraform-provider-external, terraform-provider-google, terraform-provider-helm, terraform-provider-kubernetes, terraform-provid, thunderbird, tiff, traefik2, xorg-x11-server, and xwayland).

The 7.2-rc3 kernel prepatch is out for testing. Linus said: "Things continue to look normal (the 'new normal' with slightly higher rates of commits, although I do get the feeling that we're seeing that slightly balanced out by people starting to go on summer vacation)".

Our article "Fighting the AI scraper bot scourge", published in early 2025, discussed the problem of widespread scraping of web sites in search of training data for large language models and related projects. This activity overwhelms sites with traffic. Over a year after that article is published, the problem is still growing. The hammering of sites by shadowy actors has reached new heights, and the open web is becoming increasingly difficult to maintain. Where is this traffic coming from, and what can be done about it?

QBE, a compact compiler backend developed by Quentin Carbonneaux, is a lightweight alternative to larger compiler backends such as LLVM and GCC. Designed to be small enough for a single developer to understand, QBE uses a static single-assignment (SSA) intermediate representation (IR), supports the C ABI, and serves as the backend for projects such as Hare and the cproc C11 compiler. Frontends emit the textual form of QBE's IR directly; QBE then takes care of register allocation, optimization, and native-code generation, producing assembly for the target architecture.

Security updates have been issued by AlmaLinux (aardvark-dns, cups, edk2, gstreamer1-plugins-bad-free, gstreamer1-plugins-good, gstreamer1-plugins-ugly-free, kernel, libsolv, libtasn1, libxml2, nginx:1.24, nginx:1.26, oci-seccomp-bpf-hook, python-urllib3, and tomcat), Debian (rlottie), Fedora (c-ares, k9s, kind, libXfont2, nmap, pam, perl-DBI, php, python-pendulum, tmux, and xorg-x11-server-Xwayland), Mageia (7zip and ack), Slackware (tigervnc), SUSE (alloy, cargo-c, chromium, clamav, cosign, dirmngr, firefox, flannel, fluidsynth, gnutls, go1.25, go1.26, gol, GraphicsMagick, helm, kernel-devel, libaom, libexif, openQA, os-autoinst, python-Django, python-idna, python-sqlparse, rust-keylime, rustup, sccache, SUSE Manager Client Tools, SUSE_Multi-Linux_Manager Client Tools, transmission, and warewulf4), and Ubuntu (curl, expat, golang-go.crypto, libheif, libidn, libraw, libsoup2.4, linux, linux-azure-4.15, linux-azure-fips, linux-fips, linux-gcp-4.15, linux-gcp-fips, linux-kvm, linux-oracle, linux-aws, linux-aws-fips, linux-azure-fips, linux-fips, linux-raspi, linux-xilinx-zynqmp, and python2.7, python3.5).

Kitty is a terminal emulator that runs on Linux, macOS, and the BSDs, which is notable for its speed and features such as image support and advanced font handling. It is under active development; a recent major release adds a new level of mouse support. Here, we will look at some of those features and show how the program can also be used as platform for text-based applications. Kitty is free software, released under the GPLv3.

Version 1.97.0 of the Rust programming language has been released. Changes include using a new symbol-mangling scheme by default, support for denying warnings in Cargo, and an end to the practice of hiding the linker's output after a successful build.

Security updates have been issued by AlmaLinux (389-ds-base, aardvark-dns, buildah, compat-openssl10, freeipmi, frr, gnutls, grafana, grafana-pcp, kernel, kernel-rt, libyang, nginx, openexr, pcs, perl-HTTP-Daemon, postgresql:18, python3.14-pip, skopeo, tomcat9, and wireshark), Debian (chromium and pgextwlist), Fedora (openssh, opkssh, perl-CSS-Minifier-XS, python-jiter, python-nh3, python-pendulum, rust-jiter, and upower), Mageia (openvpn and vips), Oracle (389-ds-base, aardvark-dns, compat-openssl10, container-tools:ol8, freeipmi, kernel, libyang, perl-HTTP-Daemon, python3.14-pip, and skopeo), Slackware (libXfont2, proftpd, and xorg-server), SUSE (alloy, apache2, apptainer, assimp, chromium, clamav, docker, docker-compose, dracut, glib-networking, go-sendxmpp, go1.26-openssl, gstreamer-plugins-good, haproxy, hauler, jackson-annotations, jackson-bom, jackson-core, jackson- databind, jackson-dataformats-binary, jackson-modules-base, jackson-parent, kernel, krb5, kubevirt, libslirp, libXfont2, mpv, libkpipewirerecord6, ffmpegthumbs-kf5, netty, netty-tcnative, openqa, os-autoinst, podman, python-maturin, python-msgpack, python313-yt-dlp, radare2, rust-keylime, systemd, systemd, systemd-mini, tomcat11, trivy, xorg-x11-server, and xwayland), and Ubuntu (apache2, clamav, linux-raspi, and mailcap).

Inside this week's LWN.net Weekly Edition:

• Front: Cryptography API; Iomap explanation; Negative dentries; Faster RCUs and lockless allocation for BPF; Negative dentries; LLMs in memory-management code
• Briefs: Guix vulnerabilities; OpenSSH 10.4; trusted publishing; kernel archive; CalyxOS; Quotes; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

Over on the OpenMandriva forum, the Linux distribution has reported sabotage of its repositories by a disgruntled contributor with administrative credentials. According to "AngryPenguin", an abusive incident in a distribution Matrix chat led to a user being kicked out of the chat; that "triggered a cascade of events", which led to people resigning from the distribution. Eventually, one of those people used their administrative privileges to delete part of the distribution's GitHub repository and to "publish an empty package in the cooker repository, which obsoleted all gnome and cosmic packages, which could have damaged the systems of people using gnome or cosmic". We are currently working to restore the deleted repositories and restore the functionality of the obsolete packages.

[...] We performed a full system audit and, aside from the removed packages, we found no other violations.

At the 2026 Linux Security Summit North America, Eric Biggers spoke about some of the problems with the kernel's cryptography framework, as well as the recent progress in adding library APIs to allow developers to use cryptographic functions without using the traditional crypto API. He walked through a couple of examples to demonstrate the frailty of the original API and showed how the new library API made life easier for developers and kernel maintainers.

Security updates have been issued by AlmaLinux (container-tools:rhel8, kernel-rt, libreoffice, nodejs:22, nodejs:24, opentelemetry-collector, perl-HTTP-Daemon, and python-markdown), Debian (dpkg, imagemagick, and postfix), Fedora (betterleaks, docker-compose, firefox, helm, perl-Compress-Raw-Bzip2, perl-IO-Compress, perl-JavaScript-Minifier-XS, python-cramjam, python-fastar, python-pillow-jxl-plugin, python-rignore, and tor), Oracle (grafana, grafana-pcp, and ruby:4.0), Slackware (tftp), SUSE (gi-docgen, glibc, helm, helm3, json-c-devel, kubevirt-1.6, librpmbuild10, python313-dulwich, python313-lxml_html_clean, python313-openapi-spec-validator, and sdbootutil), and Ubuntu (ruby-addressable).

William Woodruff, better known online as "yossarian", has published a blog post to make the case that users should not place their trust in trusted publishing:

Trusted Publishing is a mechanism for establishing trust between an external machine identity (like a CI/CD workflow) and one or more projects on a package index/registry. The "trust" in "Trusted Publishing" refers to that trust relationship, and not to anything else.

It is not, and cannot be, a signal for package trust or quality. You cannot use it to determine whether a package is safe or "good," and PyPI consciously stymies attempts to misuse it for that purpose by not rendering it as a "green checkmark" or anything else of the sort.

Or as another framing: Trusted Publishing is just a form of authentication. It doesn't tell you anything other than that an upload was authenticated, which all uploads to PyPI are.

LWN covered trusted publishing in June.

Puranjay Mohan shared some of the work he's been doing recently on improving the performance of read-copy-update (RCU) at the 2026 Linux Storage, Filesystem, Memory-Management, and BPF Summit; his talk would have been nice context to have earlier in the day when Harry Yoo and Alexei Starovoitov led a session about the new kmalloc_nolock() function that allows for lockless allocation from any kernel context, and which interacts with the RCU subsystem to allow that. This article therefore covers the two sessions together and in the reverse order, to provide that missing context.

Security updates have been issued by AlmaLinux (nodejs22 and nodejs24), Fedora (clamav, hplip, kernel, kernel-headers, librabbitmq, mingw-expat, mir, perl-Imager, podman-tui, prometheus-podman-exporter, python-rpds-py, rust-ashpd, rust-busd, rust-gtk4-macros, rust-inferno, rust-quick-xml, rust-reqsign-aws-v4, rust-wayland-scanner, and sandogasa), Oracle (container-tools:rhel8, kernel, mariadb:10.11, mariadb:11.8, nginx, perl:5.32, php, php:7.4, rrdtool, ruby:2.5, ruby:3.3, ruby:4.0, and uek-kernel), Red Hat (kernel, opentelemetry-collector, and python-urllib3), Slackware (c and openssh), SUSE (bind, chromedriver, cryptsetup, s390-tools, dnsmasq, jackson-annotations, jackson-core, jackson-databind, lcms2, pacemaker, perl-Cpanel-JSON-XS, perl-Crypt-SaltedHash, postfix, and python-mistune), and Ubuntu (gnutls28, gzip, openssh, php7.0, python-parsl, python3.10, python3.12, python3.14, request-tracker5, socat, sogo, and tar).

OpenSSH 10.4 has been released. In addition to a number of security and bug fixes, there are a few notable changes; this release adds experimental support for a composite post-quantum signature scheme combining ML-DSA 44 and Ed25519 as described in this IETF draft. With 10.4, if OpenSSH is compiled with sandbox support it will fail on Linux systems that have not enabled SECCOMP or NO_NEW_PRIVS; prior to this release, sshd would log an error but continue operation. See the release notes for a full list of changes.

Conversations about the kernel's filesystem implementations often involve a layer called "iomap", but relatively few people can reliably say what iomap actually is. That is just the kind of gap that LWN exists to fill. In short, iomap handles the mapping between data in the filesystem space (identified by a file of interest, and an offset within that file) and in the storage space (which may be a memory location, or a set of blocks on a storage device). Using that mapping, iomap handles a long list of common, filesystem-related tasks, allowing a lot of boilerplate code to be removed from individual filesystem implementations.

Security updates have been issued by AlmaLinux (container-tools:rhel8, grafana, grafana-pcp, kernel, ruby:2.5, and ruby:3.3), Debian (bird3, chromium, kernel, linux-6.1, mediawiki, nginx, openvpn, php-phpseclib, php8.2, php8.4, and sympa), Fedora (7zip, buildah, chromium, clamav, freerdp, leptonica, mariadb10.11, mariadb11.8, nextcloud, nsd, openqa, openvpn, os-autoinst, pdns, pdns-recursor, perl-Crypt-ScryptKDF, podman, python-jupyter-server, and python-streamlink), Mageia (mariadb and yt-dlp), Slackware (libevent, libseccomp, mozilla, mutt, and php82), SUSE (apache2, containerd, dnsmasq, docker, dracut, firewalld-legacy, gimp, glibc, golang-github-docker-libnetwork, google-guest-agent, gstreamer-plugins-bad, helm, kernel, kernel-devel, keybase-client, kitty, krb5, libarchive, libnfs, libslirp, nilfs-utils, openCryptoki, openQA, openssl-3, pacemaker, pcr-oracle, perl-DBI, perl-List-SomeUtils-XS, podman, python-pip, python-pydata-sphinx-theme, python-tornado6, python3-lxml, python311-mistune, python313-joserfc, rmt-server, sg3_utils, systemd, tracker-miners, and xdg-dbus-proxy), and Ubuntu (cifs-utils, linux-nvidia, linux-nvidia-6.17, linux-raspi-realtime, and ncurses).