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Security updates have been issued by Debian (libpam4j, libreoffice, openssl, and ruby-yajl), Fedora (ansible), Mageia (openssl), SUSE (kernel), and Ubuntu (bind9).

Apple has let itbe known that the CUPS printing system will, as of version 2.3,switch from GPLv2 to the Apache License. This change is possible becauseApple requires that contributors sign acontributor agreement [PDF] giving joint ownership of any copyrights toApple.

The LWN.net Weekly Edition for November 9, 2017 is available.

The Free Software Foundation Europe (FSFE) has released thenext version of its REUSE practices,designed to make computers understand software copyrights and licenses."The REUSE practices help software developers make simple additions to license headers which make it easier for a computer to determine what license applies to the various parts of a programs source code. By following the REUSE practices, software developers can ensure their intent to license software under a particular license is understood and more readily adhered to."

The LiMux (or Limux)initiative in Munich has been heralded as an example of both the good andbad in moving a public administration away from proprietary systems. FreeSoftware Foundation Europe (FSFE) President Matthias Kirschner reviewed thehistory of the initiative—and its recent apparent downfall—in a talk atOpen Source Summit Europe in Prague. He also looked at the broaderimplications of the project as well as asking some questions thatfree-software advocates should consider moving forward.

Security updates have been issued by Arch Linux (chromium, libzip, and openssl), Debian (chromium-browser, otrs2, slurm-llnl, and tomcat7), Fedora (kernel, libgcrypt, nodejs, php, poppler, qemu, rpm, and wget), openSUSE (chromium), Red Hat (chromium-browser and rhvm-appliance), SUSE (krb5 and qemu), and Ubuntu (openjdk-8).

USBGuard is asecurity framework for the authorization of USB devices that can be pluggedinto a Linux system. For users who want to protect a system from maliciousUSB devices or unauthorized use of USB ports on a machine, this program gives a number of fine-grained policy options for specifyinghow USB devices can interact with a host system. It is a tool similar tousbauth, which also provides an interface to create access-control policies for theUSB ports. Although kernelauthorization for USB devices already exists, programs like USBGuard makeit easy to craft policies using those mechanisms.

The 2017 Maintainers Summit, the first event of its type, managed to cover awide range of topics in a single half-day. This article, which concludesLWN's coverage of this event, picks up a fewrelatively short topics that were discussed toward the end of the session.These include a new initiative to add SPDX license tags to the kernel, theperils of cross-subsystem development, and an evaluation of the summititself.

The4.13.12,4.9.61,4.4.97,and 3.18.80 stable kernel updates areavailable. As usual, each contains a long list of important fixes andupdates.

A traditional Kernel-Summit agenda item was a slot where Linus Torvalds hadthe opportunity to discuss the aspects of the development community that hewas (or, more often, was not) happy with. In 2017, this discussion movedto the smaller Maintainers Summit. Torvalds is mostly content with the state of thecommunity, it seems, but the group still found plenty of process-related things to talk about.

Security updates have been issued by Debian (apr, apr-util, chromium-browser, libpam4j, and mupdf), Fedora (community-mysql and modulemd), Mageia (git), openSUSE (libsass, libwpd, qemu, sssd, and SuSEfirewall2), Red Hat (Red Hat JBoss Enterprise Application Platform and Red Hat JBoss Enterprise Application Platform 7.0), SUSE (qemu), and Ubuntu (openssl).

Android has been a great boon to the kernel community, having brought agreat deal of growth in both the user and the development communities. ButAndroid has also been a problem in that devices running it ship withkernels containing large amounts (often millions of lines) of out-of-treecode. That fragments the development community and makes it impossible torun mainline kernels on this hardware. The problematic side of Android wasdiscussed at the 2017 Maintainer Summit; the picture that resulted issurprisingly optimistic.

Enlightenment DR 0.22.0 has been released. Thisversion of the desktop shell features improved Wayland support,improvements to new gadget infrastructure, a sudo/ssh askpass utility gui,tiling policy improvements, and integrated per-window volume controls,along with a switch to the Meson build system.

Laurent Pinchart ran a session at the 2017 Embedded Linux Conference Europeentitled "Bash the kernel maintainers"; the idea was to get feedback fromdevelopers on their experience working with the kernel community. A fewdays later, the Maintainers Summit held a free-flowing discussion on theissues that were brought up in that session. Some changes may result fromthis discussion, but it also showed how hard it can be to change how kernelsubsystem maintainers work.

The Software Freedom Law Center (SFLC) has responded to a recent blog post from the Software Freedom Conservancy (SFC) regarding the SFC's trademark. SFLC has asked the US Patent and Trademark Office (PTO) to cancel the SFC trademark due to a likelihood of confusion between the two marks; SFC posted about the action on its blog. Now, SFLC is telling its side of the story: "At the end of September, SFLC notified the US Patent and Trademark Office that we have an actual confusion problem caused by the trademark 'Software Freedom Conservancy,' which is confusingly similar to our own pre-existing trademark. US trademark law is all about preventing confusion among sources and suppliers of goods and services in the market. Trademark law acts to provide remedies against situations that create likelihood of, as well as actual, confusion. When you are a trademark holder, if a recent mark junior to yours causes likelihood of or actual confusion, you have a right to inform the PTO that the mark has issued in error, because that’s not supposed to happen. This act of notifying the PTO of a subsequently-issued mark that is causing actual confusion is called a petition to cancel the trademark. That’s not some more aggressive choice that the holder has made; it is not an attack, let alone a 'bizarre' attack, on anybody. That’s the name of the process by which the trademark holder gets the most basic value of the trademark, which is the right to abate confusion caused by the PTO itself."

The 2017Realtime Summit (RT-Summit) was hosted by the Czech Technical University onSaturday, October 21 in Prague, just before the Embedded LinuxConference. It was attended by more than 50 individuals with backgrounds ranging fromacademic to industrial, and some local students daring enough to spend a day with thatgroup. Guest author Mathieu Poirier provides summaries of some of thetalks from the summit.

Security updates have been issued by Arch Linux (curl, lib32-curl, lib32-libcurl-compat, lib32-libcurl-gnutls, libcurl-compat, libcurl-gnutls, libmupdf, mupdf, mupdf-gl, mupdf-tools, and zathura-pdf-mupdf), CentOS (liblouis), Debian (graphicsmagick, imagemagick, irssi, openssl, openssl1.0, redis, and wordpress), Mageia (lucene, poppler, and x11-server), SUSE (libwpd and webkit2gtk3), and Ubuntu (liblouis).

The tracking of kernel regressions was discussed at the 2017 Kernel Summit; the topicmade a second appearance at the first-ever Maintainers Summit two dayslater. This session was partly a repeat of what came before for thebenefit of those (including Linus Torvalds) who weren't at the firstdiscussion, but some new ground was covered as well.

The 4.14-rc8 kernel prepatch is out fortesting. "But to actually have decided that we don't need an rc8 this release,it would have had to be really totally quiet, and it wasn't. Nothinglooks scary, but we did have a few reverts in here still, and I'lljust feel happier giving 4.14 another final week... and I really hope that _will_ be the final week, and we don't findanything new scary." Along with the various fixes, this prepatchalso adds SPDX license tags to a lot of kernel source files.

Willy Tarreau reflectson his experience maintaining the 3.10 long-term kernel on the occasionof the release of the final update, 3.10.108."First, there's no such notion of 'important fixes'. Even seriousvendors employing several kernel developers got caught missing someapparently unimportant fixes and remaining vulnerable for more than twoyears after LTS was fixed. So you can imagine the level of quality you mayexpect from a $60 WiFi router vendor claiming to apply the samepractices... The reality is that a bug is a bug, and until it's exploitedit's not considered a vulnerability."

The GitLab open-source (and open-core) project hosting site has announced that it is moving away from its Contributor License Agreement (CLA) to a Developers Certificate of Origin (DCO), which is what is used by the Linux kernel, for example, to cover contributions made to its code base. "A Contributor License Agreement (CLA) is the industry standard for open source contributions to other projects, but it's unpopular with developers, who don't want to enter into legal terms and are put off by having to review a lengthy contract and potentially give up some of their rights. Contributors find the agreement unnecessarily restrictive, and it's deterring developers of open source projects from using GitLab. We were approached by Debian developers to consider dropping the CLA, and that's what we're doing." LWN looked at some of the background of this issue back in June.

The Software Freedom Conservancy (SFC) blog reveals a recent action taken by the Software Freedom Law Center (SFLC) to try to cancel the trademark for SFC. On September 22, SFLC filed a complaint with the US Patent and Trademark Office asking that the trademark be canceled because there is a likelihood of confusion between the trademarks:"Registrant's SOFTWARE FREEDOM CONSERVANCY Mark is confusingly similar toPetitioner's SOFTWARE FREEDOM LAW CENTER Mark." On November 2, SFC filed a response that lists the defenses it plans to use. From the blog post: "We are surprised and sad that our former attorneys, who kindly helped our organization start in our earliest days and later excitedly endorsed us when we moved from a volunteer organization to a staffed one, would seek to invalidate our trademark. Conservancy and SFLC are very different organizations and sometimes publicly disagree about detailed policy issues. Yet, both non-profits are charities organized to promote the public's interest. Thus, we are especially disappointed that SFLC would waste the precious resources of both organizations in this frivolous action."

Security updates have been issued by Debian (bchunk and openjdk-8), Fedora (kernel and seamonkey), Mageia (ansible, sdl2, sdl2_image, mingw, and tomcat), Oracle (kernel and liblouis), Red Hat (liblouis and samba), Scientific Linux (liblouis), Slackware (mariadb and openssl), and SUSE (ceph, kernel, and qemu).

Shuah Khan is the maintainer of the kernel's self-test subsystem. At the2017 Kernel Summit, she presented an update on the recent developments inkernel testing and led a related discussion. Much work has happened aroundself-testing in the kernel, but there remains a lot to be done.

The 4.13.11, 4.9.60, 4.4.96, and 3.18.79 stable kernels have been released byGreg Kroah-Hartman. There are, as usual, important fixes throughout thetree in these updates and users of those kernel series should upgrade.

Security updates have been issued by Debian (thunderbird), Fedora (glusterfs, gnome-shell, java-1.8.0-openjdk, lucene, openvpn, poppler, and xen), openSUSE (xen), and Ubuntu (libreoffice and samba).

The LWN.net Weekly Edition for November 2, 2017 is available.

On the Ubuntu Insights blog, Canonical has announced that it has joined the GNOME Foundation advisory board. "We hope to share the results of our many years of user research, testing plus the needs of our large and diverse user base to help map out the best way for the entire GNOME ecosystem to benefit from our membership.The GNOME community have been very welcoming to Ubuntu, and we are already seeing the fruits of their labour in 17.10. Night Light, Captive Portal detection, the new Control Center, and a host of new features are now available to Ubuntu Desktop users by default by way of the GNOME desktop.We look forward to working closely with the GNOME Foundation, and to many years of happy collaboration."

Much software that uses the Linux kernel does so at comparativearms-length: when it needs the kernel, perhaps for a read or write, itperforms a system call, then (at least from its point of view) continuesoperation later, with whatever the kernel chooses to give it in reply. Somesoftware, however, gets pretty intimately involved with the kernel as partof its normal operation, for example by using eBPF for low-level packetprocessing. Suricata is such a program; Eric Leblondspoke about it at Kernel Recipes 2017 in a talk entitled "eBPF and XDPseen from the eyes of a meerkat".

Security updates have been issued by Debian (graphicsmagick, libdatetime-timezone-perl, openjpeg2, thunderbird, and tzdata), Fedora (curl, glusterfs, java-1.8.0-openjdk, lame, lucene, SDL2, systemd, and xen), Red Hat (python-django), and Ubuntu (linux-lts-trusty and quagga).

When a kernel developer wants to communicate a message to user space, be itfor debugging or to report a serious problem with the system, the venerableprintk() function is usually the tool of choice. But, as SteveRostedt (accompanied by Petr Mladek and Sergey Senozhatsky) noted during abrief session at the 2017 Kernel Summit, printk() has not aged well. In particular, it can affect theperformance of the system as a whole; the roots of that problem and apossible solution were discussed, but a real solution will have to wait forthe appearance of the code.

On his blog, Sebastian Kügler sets out a roadmap for Plasma Mobile, which is a project that "aims to become a complete and open software system for mobile devices". There is already a prototype version available, the next step is the "feature phone" milestone (which will be followed by the "basic smartphone" and "featured smartphone" milestones). "The feature phone milestone is what we’re working on right now. This involves taking the prototype and fixing all the basic things to turn it into something usable. Usable doesn’t mean 'usable for everyone', but it should at least be workable for a subset of people that only rely on basic features — 'simple' things.Core features should work flawlessly once this milestone is achieved. With core features, we’re thinking along the lines of making phone calls, using the address book, manage hardware functions such as network connectivity, volume, screen, time, language, etc.. Aside from these very core things for a phone, we want to provide decent integration with a webbrowser (or provide our own), app store integration likely using store.kde.org, so you can get apps on and off the device, taking photos, recording videos and watching these media. Finally, we want to settle for an SDK which allows third party developers to build apps to run on Plasma Mobile devices.Getting this to work is no small feat, but it allows us to receive real-world feedback and provide a stable base for third-party products. It makes Plasma Mobile a viable target for future product development."

The kernel development community has run for some years without anybodytracking regressions; that changed one year ago when Thorsten Leemhuisstepped up to the task. Two conversations were held on the topic at the2017 Kernel and Maintainers summits in Prague; this article covers thefirst of those, held during the open Kernel-Summit track.

Security updates have been issued by Debian (libav, quagga, wordpress, and wpa), Mageia (exiv2, irssi, opensc_etc, procmail, rpm, and wget), SUSE (kernel), and Ubuntu (kernel, linux, linux-raspi2, linux-gcp, linux-hwe, and linux-lts-xenial).

Some technologies find their way into the kernel almost immediately; othersneed to go through multiple iterations over a number of years first.Restartable sequences, a mechanism for lockless concurrency control in user space, fallinto the latter category. At the 2017 Kernel Summit, Mathieu Desnoyersdiscussed yet another implementation of this concept — but this one may notbe the last word either.

The annual GStreamerconference took place October 21-22 in Prague, (unofficially)co-located with the EmbeddedLinux Conference Europe. The GStreamer project is alibrary for connecting media elements such as sources, encoders and decoders, filters,streaming endpoints, and output sinks of all sorts into a fullycustomizable pipeline. It offers cross-platform support, a large set ofplugins, modernstreaming and codec formats, and hardware acceleration as some of its features. Kickingoff this year's conference was Tim-Philipp Müller with his report on thelast 12 months of development and what we can look forward to next.

Security updates have been issued by Arch Linux (apr, apr-util, chromium, and wget), CentOS (tomcat and tomcat6), Debian (curl, git-annex, golang, shadowsocks-libev, and wget), Fedora (libextractor and sssd), Gentoo (apache, asterisk, jython, oracle-jdk-bin, and xorg-server), openSUSE (chromium, curl, gcc48, GraphicsMagick, hostapd, kernel, libjpeg-turbo, libvirt, mysql-community-server, openvpn, SDL2, tcpdump, and wget), Oracle (tomcat and tomcat6), Red Hat (chromium-browser, tomcat, and tomcat6), Scientific Linux (tomcat and tomcat6), Slackware (php and wget), SUSE (firefox, mozilla-nss, kernel, wget, and xen), and Ubuntu (mysql-5.5, poppler, and wget).

The 4.14-rc7 kernel prepatch is out fortesting. "Still, considering the issues we've had, I likely will doan rc8 unless this upcoming week ends up being _so_ quiet that there's nopoint. Which while unlikely would be lovely..."

Tracepoints provide a great deal of visibility into the inner workings ofthe kernel, which is both a blessing and a curse. The advantages ofknowing what the kernel is doing are obvious; the disadvantage is thattracepoints risk becoming a part of the kernel's ABI if applications startto depend on them. The need to maintain tracepoints could impede theongoing development of the kernel. Ways of avoiding this problem have beendiscussed for years; at the 2017 Kernel Summit, Steve Rostedt talked aboutyet another scheme.

Security updates have been issued by CentOS (ntp and wget), Debian (exiv2, mosquitto, and zoneminder), Mageia (upx and virtualbox), Oracle (ntp and wget), Red Hat (wget), Scientific Linux (wget), SUSE (xen), and Ubuntu (irssi, systemd, and wget).

The4.13.10,4.9.59,4.4.95, and3.18.78 stable kernel updates have beenreleased; each contains the usual set of important fixes and updates.

The 2017Realtime Summit was held October 21 at Czech Technical Universityin Prague to discuss all manner of topics related to realtime Linux.Nearly two years ago, a collaborativeproject was formed with the goal of mainlining the realtime patch set. At thesummit, projectlead Thomas Gleixner reported on the progress that has been made and theplans for the future.

Security updates have been issued by Fedora (cacti, glibc, kernel, libXfont, libXfont2, mingw-poppler, nodejs-forwarded, procmail, SDL2, thunderbird, and tnef), openSUSE (freeradius-server, kernel, and libraw), Oracle (kernel), Red Hat (ntp), Scientific Linux (ntp), Slackware (irssi), SUSE (kernel), and Ubuntu (python-werkzeug).

The LWN.net Weekly Edition for October 26, 2017 is available.

The Linux Foundation has announcedthe availability of its roughly annual report on kernel development."This is the eighth such report that is released on a roughly annualbasis to help illustrate the Linux kernel development process and the workthat defines the largest collaborative project in the history ofcomputing. This year’s paper covers work completed through Linux kernel4.13, with an emphasis on releases 4.8 to 4.13.". This report,written by LWN editor Jonathan Corbet and Greg Kroah-Hartman, will havelittle that's new to regular LWN readers, but there is a set of nicedeveloper profiles.

<p>Academics generate enormous amounts of software, some of which inspirescommercial innovations in networking and other areas. But little academicsoftware gets released to the public and even less enters common use. Issome vast "dark matter" being overlooked in the academic community? Wouldthe world benefit from academics turning more of their software into freeand open projects?

The SciPy project has announced the release of SciPy 1.0. The "Python-based ecosystem of open-source software for mathematics, science, and engineering" has been around for 16 years since version 0.1 and, in reality, the 1.0 designation is overdue. "Some key project goals, both technical (e.g. Windows wheels and continuousintegration) and organisational (a governance structure, code of conductand aroadmap), have been achieved recently.Many of us are a bit perfectionist, and therefore are reluctant to callsomething '1.0' because it may imply that it's 'finished' or 'we are 100%happywith it'. This is normal for many open source projects, however thatdoesn'tmake it right. We acknowledge to ourselves that it's not perfect, and thereare some dusty corners left (that will probably always be the case).Despitethat, SciPy is extremely useful to its users, on average has high qualitycodeand documentation, and gives the stability and backwards compatibilityguarantees that a 1.0 label imply." Beyond the Windows wheels (a binary distribution format) mentioned above, there are some other new features in the release: continuous-integration coverage for macOS and Windows, a set of new ordinary differential equation solvers and a unified interface to them, two new trust region optimizers and a new linear programming method,many new BLAS and LAPACK functions were wrapped, and more.

Security updates have been issued by Debian (curl and mupdf), Fedora (glibc, SDL2, and sssd), Mageia (kernel, kernel-linus, and kernel-tmb), and Ubuntu (apache2 and subversion).

One of the key values provided by an operating system like Linux isthat it provides abstract interfaces to concrete devices. Though theoriginal "character device" and "block device" abstractions have beensupplemented with various others including "network device" and"bitmap display", the original two have not lost their importance. Theblock device interface, in particular, is still central to managingpersistent storage and, even with the growth of persistent memory, thiscentral role is likely to remain for some time. Unpacking andexplaining some of that role is the goal of this pair of articles.

Security updates have been issued by CentOS (kernel), Fedora (check-mk and dnsmasq), Mageia (kernel-linus, kernel-tmb, mysql-connector-java, and recode), openSUSE (irssi and jq), Red Hat (httpd24, java-1.6.0-sun, and java-1.7.0-oracle), Slackware (curl), SUSE (openvpn), and Ubuntu (bzr, curl, icu, libffi, libidn, mysql-5.5, mysql-5.7, nvidia-graphics-drivers-384, pacemaker, and webkit2gtk).