Provided by: nbdkit_1.42.2-1ubuntu1_amd64 
NAME
nbdkit-release-notes-1.28 - release notes for nbdkit 1.28
DESCRIPTION
These are the release notes for nbdkit stable release 1.28. This describes the major changes since 1.26.
nbdkit 1.28.0 was released on 23 September 2021.
Security
CVE-2021-3716 reset structured replies on starttls
nbdkit was vulnerable to injected plaintext when upgrading to a secure connection. For the full
announcement see https://www.redhat.com/archives/libguestfs/2021-August/msg00083.html (Eric Blake).
All past security issues and information about how to report new ones can be found in nbdkit-security(1).
Plugins
nbdkit-data-plugin(1) has new "le<NN>:" and "be<NN>:" prefixes for little and big endian words. Also the
plugin tries much harder to optimize expressions. The test suite has been greatly expanded to catch
potential regressions.
nbdkit-floppy-plugin(1) now allows you to reserve free space (Nolan Leake).
nbdkit-ssh-plugin(1) no longer references SHA1 host keys as part of the effort to remove insecure
algorithms (Daniel Berrangé).
nbdkit-vddk-plugin(1) reports "can_flush" and "can_fua" based on what the version of VDDK supports. New
debug flag -D vddk.stats=1 prints the amount of time spent in VDDK calls on exit which can be useful for
profiling performance.
Filters
nbdkit-cow-filter(1) and nbdkit-cache-filter(1) no longer break up large read requests into page-sized
requests. In addition the default block size for both filters is now 64K. Both changes greatly improve
performance.
nbdkit-cache-filter(1) has a new "cache-on-read=/PATH" parameter allowing callers to enable and disable
the cache-on-read feature at runtime. Also there is a new "cache-min-block-size" parameter letting you
select the block size at runtime (thanks Martin Kletzander).
nbdkit-cow-filter(1) has a new "cow-on-read" parameter which works similarly to the corresponding cache
filter feature. The new "cow-block-size" parameter lets you select the block size at runtime.
nbdkit-cow-filter(1) has less verbose debugging. To restore the old debug output use -D cow.verbose=1
nbdkit-delay-filter(1) has new "delay-open" and "delay-close" parameters to inject delays when clients
connect and disconnect. Delay filter parameters are now parsed more accurately (thanks Ming Xie).
Language bindings
The OCaml bindings now call "caml_shutdown" when unloading the plugin. This causes "Stdlib.at_exit"
handlers to run correctly, closes file descriptors, releases dependent shared libraries and frees memory.
Valgrind on OCaml plugins should not show any false positives about leaked memory.
OCaml and Python bindings may now use the ".cleanup" method.
References to Python 2 in nbdkit-python-plugin(3) have been removed.
Server
Fix captive nbdkit $uri variable so when TLS is used the URI is constructed with the "nbds:" prefix.
Additionally add a new variable $tls which can be used by the subprocess to tell if TLS is enabled.
Debug messages are now printed atomically. This means that debug messages are no longer broken up across
multiple lines if there are other processes writing to stderr at the same time (which often happened when
using captive nbdkit).
Enhanced valgrind support (./configure --enable-valgrind) can now be enabled safely and with no
performance impact even in production builds (Eric Blake).
API
Plugins or filters using "nbdkit_nanosleep" now don't hang if the client closes the socket abruptly
(thanks Ming Xie).
Bug fixes
nbdkit-data-plugin(1) and nbdkit-memory-plugin(1) using allocator=malloc no longer crash because of
memory corruption in some corner cases (only seen on s390x, but could happen on other architectures).
Meanwhile "allocator=zstd" no longer crashes when zeroing unallocated space.
Tests
Tests now use the new "GLIBC_TUNABLES" feature, replacing "MALLOC_CHECK_" on glibc ≥ 2.34 (thanks Eric
Blake, Siddhesh Poyarekar).
Build
configure.ac now uses spaces consistently, and has been modernized to support the latest autotools (Eric
Blake).
podwrapper.pl has been unified (almost) with the copy in libnbd.
Continue fuzzing using AFL++. Updated the fuzzing documentation.
SEE ALSO
nbdkit(1).
AUTHORS
Authors of nbdkit 1.28:
Daniel P. Berrangé
Eric Blake
Martin Kletzander
Nolan Leake
Richard W.M. Jones
COPYRIGHT
Copyright Red Hat
LICENSE
Redistribution and use in source and binary forms, with or without modification, are permitted provided
that the following conditions are met:
• Redistributions of source code must retain the above copyright notice, this list of conditions and
the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of Red Hat nor the names of its contributors may be used to endorse or promote
products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
DAMAGE.
nbdkit-1.42.2 2025-04-02 nbdkit-release-notes-1.28(1)