All posts by corbet

Ubuntu forums compromised

Post Syndicated from corbet original

Canonical has disclosed
that the Ubuntu forum system has been compromised. “The attacker had
the ability to inject certain formatted SQL to the Forums database on the
Forums database servers. This gave them the ability to read from any table
but we believe they only ever read from the ‘user’ table. They used this
access to download portions of the ‘user’ table which contained usernames,
email addresses and IPs for 2 million users. No active passwords were

Kernel prepatch 4.7-rc7

Post Syndicated from corbet original

Linus has released the 4.7-rc7 kernel
prepatch. “Anyway, there’s a couple of regressions still being looked at, but
unless anything odd happens, this is going to be the last rc. However,
due to my travel schedule, I won’t be doing the final 4.7 next
weekend, and people will have two weeks to report (and fix) any
remaining bugs.

Yeah, that’s the ticket. My travel schedule isn’t screwing anything
up, instead think of it as you guys getting a BONUS WEEK! Yay!”

See the current list of reported
for the known issues remaining in the 4.7 kernel.

[$] Python’s os.urandom() in the absence of entropy

Post Syndicated from corbet original

Python applications, like those written in other languages, often need to
obtain random data for purposes ranging from cryptographic key generation
to initialization of scientific models. For years, the standard way of
getting that data is
via a call to os.urandom(), which is documented to “return a
string of n random bytes suitable for cryptographic use.
” An
enhancement in Python 3.5 caused a subtle change in how
os.urandom() behaves on Linux systems, leading to some long,
heated discussions
about how randomness should be obtained in Python programs. When the dust
settles, Python benevolent dictator for life (BDFL) Guido van Rossum will
have the unenviable task of choosing between two competing proposals.

[$] Kernel documentation with Sphinx, part 1: how we got here

Post Syndicated from corbet original

The last time LWN looked at formatted kernel documentation
in January, it seemed like the merging of AsciiDoc support for the
kernel’s structured source-code documentation (“kernel-doc”) comments, was
imminent. As Jonathan Corbet, in the capacity of the kernel documentation
maintainer, wrote: "A good-enough solution that exists now
should not be held up overly long in the hopes that vague ideas for
something else might turn into real, working code.
" Sometimes,
however, the threat that something not quite perfect might be merged
is enough to motivate people to turn those vague ideas into something

Subscribers can click below to see the full story by guest author (and the developer behind most of the Sphinx work) Jani Nikula.

Extracting Qualcomm’s KeyMaster Keys – Breaking Android Full Disk Encryption (Bits Please)

Post Syndicated from corbet original

The “Bits Please” blog has a
detailed description
of how one breaks full-disk encryption on an
Android phone. Included therein is a lot of information on how full-disk
encryption works on Android devices and its inherent limitations.
Instead of creating a scheme which directly uses the hardware key
without ever divulging it to software or firmware, the code above performs
the encryption and validation of the key blobs using keys which are
directly available to the TrustZone software! Note that the keys are also
constant – they are directly derived from the SHK (which is fused into the
hardware) and from two ‘hard-coded’ strings.
Let’s take a moment to explore some of the implications of this

etcd 3.0 released

Post Syndicated from corbet original

CoreOS has announced the
availability of version 3.0 of the etcd distributed key-value store.
etcd 3.0 marks the first stable release of the etcd3 API and data
model. Upgrades are simple, because the same etcd2 JSON endpoints and
internal cluster protocol are still provided in etcd3. Nevertheless, etcd3
is a wholesale API redesign based on feedback from etcd2 users and
experience with scaling etcd2 in practice. This post highlights some
notable etcd3 improvements in efficiency, reliability, and concurrency

PulseAudio 9.0 is out

Post Syndicated from corbet original

The PulseAudio 9.0 release is out. Changes include improvements to
automatic routing, beamforming support, use of the Linux memfd mechanism for transport, higher
sample-rate support, and more; see the
release notes
for details.

See also: this
article from Arun Raghavan
on how the beamforming feature works.
The basic idea is that if you have a number of microphones (a mic
array) in some known arrangement, it is possible to ‘point’ or steer the
array in a particular direction, so sounds coming from that direction are
made louder, while sounds from other directions are rendered softer

[$] How many -stable patches introduce new bugs?

Post Syndicated from corbet original

The -stable kernel release process faces a contradictory set of constraints.
Developers naturally want to get as many fixes into -stable as possible
but, at the same time, there is a strong desire to avoid introducing new
regressions there. Each -stable release is, after all, intended to be more
stable than its predecessor. At times there have been complaints that
-stable is too accepting and too prone to regressions, but not many
specifics. But, it turns out, this is an area where at least a little bit
of objective research can be done.

Project Triforce: Run AFL on Everything!

Post Syndicated from corbet original

The developers of “Project Triforce,” an effort to run the “american fuzzy
lop” fuzz-testing tool in a system-wide manner, have posted a
detailed description
of what they are up to.
AFL is an awesome tool. The power of an easy to use, feedback-driven
fuzzer has produced an absolutely staggering number of bugs. Still, at
first AFL required being able to build the executable, something sadly not
available on a lot of targets. With the addition of AFL’s qemu_mode, it
became possible to fuzz binaries without source, exposing a whole new world
of targets to AFL. I’d been on a number of Linux container engagements
recently where we’d managed to escape through kernel exploits. I fell
asleep one night to several AFL screens running, and I awoke suddenly with
a crazy idea: ‘Run AFL on the Linux Kernel.’

A couple of unpleasant local kernel vulnerabilities

Post Syndicated from corbet original

The just-released 4.6.3, 4.4.14, and 3.14.73 stable kernels contain a set
of netfilter fixes that, it has just been disclosed, fix a couple of severe
local privilege-escalation vulnerabilities. Anybody who is running a site
with user and network namespaces enabled will want to update their kernels
in short order. The fixes were originally committed into 4.6-rc2 in April
with no comment regarding their implications.

Xen 4.7 released

Post Syndicated from corbet original

Version 4.7 of the Xen hypervisor has been released. “With dozens of
major improvements, many more bug fixes and small improvements, and
significant improvements to Drivers and Devices, Xen Project 4.7 reflects a
thriving community around the Xen Project Hypervisor.
” Some of the
new features include live patching, better dom0 robustness, better
migration support between non-identical hosts, scheduler improvements, and
more. See the
release notes
for more information.

Sony agrees to pay millions to gamers to settle PS3 Linux debacle (ars technica)

Post Syndicated from corbet original

Back in 2009, Sony removed the “install other
OS” option
from its PS3 game consoles, removing the ability to install
Linux on those machines. It then went after developers who figured out how
to jailbreak the device. Ars technica reports
that Sony has now settled a class-action lawsuit over those actions.
Under the terms of the accord, which has not been approved by
a California federal judge yet, gamers are eligible to receive $55 if they
used Linux on the console. The proposed settlement, which will be vetted by
a judge next month, also provides $9 to each console owner that bought a
PS3 based on Sony’s claims about ‘Other OS’ functionality.
” The
lawyers, instead, get over $2 million.

Announcing Flatpak

Post Syndicated from corbet original

Not to be left behind by a certain competing project, the developers of the
Flatpak packaging system have put out a press
proclaiming its virtues. “The Linux desktop has long
been held back by platform fragmentation. This has been a burden on
developers, and creates a high barrier to entry for third party application
developers. Flatpak aims to change all that. From the very start its
primary goal has been to allow the same application to run across a myriad
of Linux distributions and operating systems. In doing so, it greatly
increases the number of users that application developers can easily

Fedora 24 released

Post Syndicated from corbet original

After several schedule slips, the Fedora 24 release is available.
The Fedora Project has embarked on a great journey… redefining what
an operating system should be for users and developers. Such innovation
does not come overnight, and Fedora 24 is one big step on the road to
the next generation of Linux distributions. But that does not mean that
Fedora 24 is some ‘interim’ release; there are great new features for
Fedora users to deploy in their production environments right now!

See the
Fedora 24 approved features list
for an idea of what’s in this