In commit b5ee8bebfc ("MINOR: server: always call ssl->destroy_srv when available"), we made it so srv_drop() doesn't depend on proxy to perform server cleanup. It turns out this is now mandatory, because during deinit, free_proxy() can occur before the final srv_drop(). This is the case when using Lua scripts for instance. In 2a9436f96 ("MINOR: lbprm: Add method to deinit server and proxy") we added a freeing check under srv_drop() that depends on the proxy. Because of that UAF may occur during deinit when using a Lua script that manipulate server objects. To fix the issue, let's perform the lbprm server deinit logic under free_proxy() directly, where the DEINIT server hooks are evaluated. Also, to prevent similar bugs in the future, let's explicitly document in srv_drop() that server cleanups should assume that the proxy may already be freed. No backport needed unless 2a9436f96 is.
HAProxy
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:
- 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)
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.