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Willy Tarreau 061754b249 BUG/MEDIUM: fd: make fd_delete() support being called from a different group
There's currently a problem affecting thread groups. Stopping a listener
from a different group than the one that runs this listener will trigger
the BUG_ON() in fd_delete(). This typically happens by issuing "disable
frontend f" on the CLI for the following config since the CLI runs on
group 1:

    global
        nbthread 2
        thread-groups 2
        stats socket /tmp/sock1 level admin

    frontend f
        mode http
        bind abns@frt-sock thread 2

This happens because abns sockets cannot be suspended so here this
requires a full stop.

A first approach would consist in isolating the caller during such rare
operations but it turns out that fd_delete() is not robust against even
such calling conditions, because it uses its own thread mask with an FD
that may be in a different group, and even though the threads would be
isolated and running_mask should be zero, we must not mix thread masks
from different groups like this.

A better solution consists in replacing the bug condition detection with
a self-protection. After all it's not trivial to figure all likely call
places, and forcing upper layers to protect the code is not clean if we
can do it at the bottom. Thus this is what is being done now. We detect
a thread group mismatch, and if so, we forcefully isolate ourselves and
entirely clean the socket. This has the merit of being much more robust
and easier to use (and harder to misuse). Given that such operations are
very rare (actually when they happen a crash follows), it's not a problem
to waste some time isolating the caller there.

This must be backported to 2.7, along with this previous patch:

  BUG/MINOR: fd: used the update list from the fd's group instead of tgid
2023-02-27 19:26:42 +01:00
.github CI: Reformat matrix.py using black 2023-01-03 16:28:34 +01:00
addons MINOR: stconn: Always report READ/WRITE event on shutr/shutw 2023-02-22 15:59:16 +01:00
admin BUILD: halog: fix missing double-quote at end of help line 2022-11-25 11:11:41 +01:00
dev MEDIUM: ring: make the offset relative to the head/tail instead of absolute 2023-02-24 09:26:30 +01:00
doc DOC: config: Replace TABs by spaces 2023-02-27 18:01:42 +01:00
examples EXAMPLES: remove completely outdated acl-content-sw.cfg 2022-05-30 18:14:24 +02:00
include MEDIUM: mux-quic: Don't expect data from server as long as request is unfinished 2023-02-27 17:45:45 +01:00
reg-tests REGTESTS: cache: Use rxresphdrs to only get headers for 304 responses 2023-02-22 16:12:45 +01:00
scripts SCRIPTS: run-regtests: add a version check 2022-11-30 18:44:33 +01:00
src BUG/MEDIUM: fd: make fd_delete() support being called from a different group 2023-02-27 19:26:42 +01:00
tests TESTS: add a unit test for one_among_mask() 2022-06-21 20:29:57 +02:00
.cirrus.yml CI: cirrus-ci: bump FreeBSD image to 13-1 2022-09-09 13:30:17 +02:00
.gitattributes
.gitignore CLEANUP: exclude udp-perturb with .gitignore 2022-09-16 15:47:04 +02:00
.mailmap DOC: update Tim's address in .mailmap 2021-09-16 09:14:14 +02:00
.travis.yml CI: travis-ci: temporarily disable arm64 builds 2021-08-07 07:28:15 +02:00
BRANCHES
CHANGELOG [RELEASE] Released version 2.8-dev4 2023-02-14 16:55:17 +01:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
INSTALL MINOR: version: mention that it's development again 2022-12-01 15:24:10 +01:00
LICENSE
MAINTAINERS CLEANUP: assorted typo fixes in the code and comments 2022-11-30 14:02:36 +01:00
Makefile BUILD: makefile: fix PCRE overriding specific lib path 2023-02-03 09:42:49 +01:00
README
SUBVERS
VERDATE [RELEASE] Released version 2.8-dev4 2023-02-14 16:55:17 +01:00
VERSION [RELEASE] Released version 2.8-dev4 2023-02-14 16:55:17 +01:00

The HAProxy documentation has been split into a number of different files for
ease of use.

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 :

  - doc/intro.txt for a quick introduction on HAProxy
  - doc/configuration.txt for the configuration's reference manual
  - doc/lua.txt for the Lua's reference manual
  - doc/SPOE.txt for how to use the SPOE engine
  - doc/network-namespaces.txt for how to use network namespaces under Linux
  - doc/management.txt for the management guide
  - doc/regression-testing.txt for how to use the regression testing suite
  - doc/peers.txt for the peers protocol reference
  - doc/coding-style.txt for how to adopt HAProxy's coding style
  - doc/internals for developer-specific documentation (not all up to date)