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32f0cd3242
When a log directive is defined in the global section, each time we use
"log global" in a proxy section, the global log directives are duplicated
for the current proxy. This works by creating a new proxy logger struct
and duplicating every members for each global one.
However, smp_rgs logger member is a special pointer member that is
allocated when "range" is used on a log directive. Currently, we simply
copy the array pointer (from the global one), instead of creating our own
copy. Because of that, range log sampling may not work properly in some
situations prior to 3f1284560 ("MINOR: log: remove the unused curr_idx in
struct smp_log_range") when used in global log directives, for instance:
global
log 127.0.0.1:5114 format raw sample 1-2,3:4 local0 info # should receive 75% of all proxy logs
log 127.0.0.1:5115 format raw sample 4:4 local0 info # should receive 25% of all proxy logs
listen proxy1
log global
listen proxy2
log global
May not work as expected, because curr_idx was stored within smp_rgs array
member prior to 3f1284560, and due to this bug, it happens to be shared
between every log directive inherited from a "global" one. The result is
that curr_idx counter will not behave properly because the index will be
increased globally instead of per-log directive, and it could even suffer
from concurrent thread accesses under load since we don't own the global
log directive's lock when manipulating it.
Another issue that was revealed because of this bug is that the smp_rgs
array allocated during config parsing is never freed in free_logger(),
resulting in small memory leak during clean exit.
To fix these issues all at once, let's properly duplicate smp_rgs logger
struct member in dup_logger() like we already do for other special members
so that every log directive have its own sms_rgs copy, and then
systematically free it in free_logger().
While this bug affects all stable versions (including 2.4), it's probably
best to not backport this beyond 2.6 because of 211ea252d
("BUG/MINOR: logs: fix logsrv leaks on clean exit") prerequisite that
first appears in 2.6.
[ada: for versions prior to 2.9, 969e212
("MINOR: log: add dup_logsrv() helper function") and 76acde91
("BUG/MINOR: log: keep the ref in dup_logger()") must be backported
first.
Note: Some ctx adjustments should be performed because 'logger' struct
used to be named 'logsrv' in the past and 2.9 introduced logger target
struct member. Thus it's probably easier to manually apply 76acde91 and
the current bugfix by hand directly on top of 969e212.
]
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)