HAProxy - Load balancer
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Aurelien DARRAGON aeff2a3b2a BUG/MEDIUM: hlua_fcn: ensure systematic watcher cleanup for server list iterator
In 358166a ("BUG/MINOR: hlua_fcn: restore server pairs iterator pointer
consistency"), I wrongly assumed that because the iterator was a temporary
object, no specific cleanup was needed for the watcher.

In fact watcher_detach() is not only relevant for the watcher itself, but
especially for its parent list to remove the current watcher from it.

As iterators are temporary objects, failing to remove their watchers from
the server watcher list causes the server watcher list to be corrupted.

On a normal iteration sequence, the last watcher_next() receives NULL
as target so it successfully detaches the last watcher from the list.
However the corner case here is with interrupted iterators: users are
free to break away from the iteration loop when a specific condition is
met for instance from the lua script, when this happens
hlua_listable_servers_pairs_iterator() doesn't get a chance to detach the
last iterator.

Also, Lua doesn't tell us that the loop was interrupted,
so to fix the issue we rely on the garbage collector to force a last
detach right before the object is freed. To achieve that, watcher_detach()
was slightly modified so that it becomes possible to call it without
knowing if the watcher is already detached or not, if watcher_detach() is
called on a detached watcher, the function does nothing. This way it saves
the caller from having to track the watcher state and makes the API a
little more convenient to use. This way we now systematically call
watcher_detach() for server iterators right before they are garbage
collected.

This was first reported in GH #3055. It can be observed when the server
list is browsed one than more time when it was already browsed from Lua
for a given proxy and the iteration was interrupted before the end. As the
watcher list is corrupted, the common symptom is watcher_attach() or
watcher_next() not ending due to the internal mt_list call looping
forever.

Thanks to GH users @sabretus and @sabretus for their precious help.

It should be backported everywhere 358166a was.
2025-08-05 13:06:46 +02:00
.github CI: github: skip a ssl library version when latest is already in the list 2025-07-07 19:46:07 +02:00
addons MINOR: applet: Add support for flags on applets with a flag about the new API 2025-07-25 15:44:02 +02:00
admin BUG/MINOR: halog: exit with error when some output filters are set simultaneosly 2025-07-17 17:22:37 +02:00
dev DEV: gdb: add a memprofile decoder to the debug tools 2025-07-16 15:33:33 +02:00
doc [RELEASE] Released version 3.3-dev5 2025-07-28 11:26:22 +02:00
examples MINOR: mailers: warn if mailers are configured but not actually used 2025-06-27 16:41:18 +02:00
include BUG/MEDIUM: hlua_fcn: ensure systematic watcher cleanup for server list iterator 2025-08-05 13:06:46 +02:00
reg-tests CLEANUP: assorted typo fixes in the code, commits and doc 2025-07-10 19:49:48 +02:00
scripts BUILD: adjust scripts/build-ssl.sh to modern CMake system of QuicTLS 2025-07-11 05:04:31 +02:00
src BUG/MEDIUM: hlua_fcn: ensure systematic watcher cleanup for server list iterator 2025-08-05 13:06:46 +02:00
tests TESTS: Fix build for filltab25.c 2025-04-03 15:59:41 +02:00
.cirrus.yml CI: cirrus-ci: bump FreeBSD image to 14-2 2025-02-12 13:18:55 +01:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore MINOR: tevt/dev: Add term_events tool 2025-01-31 10:41:50 +01:00
.mailmap DOC: update Tim's address in .mailmap 2021-09-16 09:14:14 +02:00
.travis.yml MEDIUM: mworker: remove USE_SYSTEMD requirement for -Ws 2024-11-20 12:07:38 +01:00
BRANCHES DOC: fix some spelling issues over multiple files 2021-01-08 14:53:47 +01:00
BSDmakefile BUILD: makefile: commit the tiny FreeBSD makefile stub 2023-05-24 17:17:36 +02:00
CHANGELOG [RELEASE] Released version 3.3-dev5 2025-07-28 11:26:22 +02:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2025-04-02 11:12:20 +02:00
INSTALL MINOR: version: mention that it's development again 2025-05-28 16:46:15 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS MAJOR: spoe: Let the SPOE back into the game 2024-05-22 09:04:38 +02:00
Makefile MEDIUM: httpclient: split the CLI from the actual httpclient API 2025-07-01 15:46:04 +02:00
README.md DOC: change the link to the FreeBSD CI in README.md 2024-06-03 15:21:29 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 3.3-dev5 2025-07-28 11:26:22 +02:00
VERSION [RELEASE] Released version 3.3-dev5 2025-07-28 11:26:22 +02:00

HAProxy

alpine/musl AWS-LC openssl no-deprecated Illumos NetBSD FreeBSD VTest

HAProxy logo

HAProxy is a free, very fast and reliable reverse-proxy offering high availability, load balancing, and proxying for TCP and HTTP-based applications.

Installation

The INSTALL file describes how to build HAProxy. A list of packages is also available on the wiki.

Getting help

The discourse and the mailing-list are available for questions or configuration assistance. You can also use the slack or IRC channel. Please don't use the issue tracker for these.

The issue tracker is only for bug reports or feature requests.

Documentation

The HAProxy documentation has been split into a number of different files for ease of use. It is available in text format as well as HTML. The wiki is also meant to replace the old architecture guide.

Please refer to the following files depending on what you're looking for:

  • INSTALL for instructions on how to build and install HAProxy
  • BRANCHES to understand the project's life cycle and what version to use
  • LICENSE for the project's license
  • CONTRIBUTING for the process to follow to submit contributions

The more detailed documentation is located into the doc/ directory:

License

HAProxy is licensed under GPL 2 or any later version, the headers under LGPL 2.1. See the LICENSE file for a more detailed explanation.