Mirror of the official PostgreSQL GIT repository. Note that this is just a *mirror* - we don't work with pull requests on github. To contribute, please see https://wiki.postgresql.org/wiki/Submitting_a_Patch
Go to file
Andres Freund fa6af9b25e localbuf: Fix dangerous coding pattern in GetLocalVictimBuffer()
If PinLocalBuffer() were to modify the buf_state, the buf_state in
GetLocalVictimBuffer() would be out of date. Currently that does not happen,
as PinLocalBuffer() only modifies the buf_state if adjust_usagecount=true and
GetLocalVictimBuffer() passes false.

However, it's easy to make this not the case anymore - it cost me a few hours
to debug the consequences.

The minimal fix would be to just refetch the buf_state after after calling
PinLocalBuffer(), but the same danger exists in later parts of the
function. Instead, declare buf_state in the narrower scopes and re-read the
state in conditional branches.  Besides being safer, it also fits well with
an upcoming set of cleanup patches that move the contents of the conditional
branches in GetLocalVictimBuffer() into helper functions.

I "broke" this in 794f259447.

Arguably this should be backpatched, but as the relevant functions are not
exported and there is no actual misbehaviour, I chose to not backpatch, at
least for now.

Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
2025-03-15 22:07:48 -04:00
.github Add CODE_OF_CONDUCT.md, CONTRIBUTING.md, and SECURITY.md. 2024-07-02 13:03:58 -05:00
config Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
contrib pg_noreturn to replace pg_attribute_noreturn() 2025-03-13 12:37:26 +01:00
doc doc: Explain more thoroughly when a table rewrite is needed 2025-03-14 20:44:59 +01:00
src localbuf: Fix dangerous coding pattern in GetLocalVictimBuffer() 2025-03-15 22:07:48 -04:00
.cirrus.star Remove duplicate words in docs and code comments. 2023-10-09 09:18:47 +05:30
.cirrus.tasks.yml ci: Remove installation of libcurl 2025-03-05 22:12:20 +01:00
.cirrus.yml ci: Test NetBSD and OpenBSD 2025-02-12 09:40:07 -05:00
.dir-locals.el Make Emacs perl-mode indent more like perltidy. 2019-01-13 11:32:31 -08:00
.editorconfig Add script to keep .editorconfig in sync with .gitattributes 2025-02-01 10:09:45 +01:00
.git-blame-ignore-revs Add b955df443 to .git-blame-ignore-revs 2025-03-13 12:44:26 +13:00
.gitattributes Add script to keep .editorconfig in sync with .gitattributes 2025-02-01 10:09:45 +01:00
.gitignore Update top-level .gitignore. 2022-12-04 15:23:00 -05:00
.mailmap Add a Git .mailmap file 2024-11-05 13:56:02 +01:00
aclocal.m4 autoconf: Move export_dynamic determination to configure 2022-12-06 18:55:28 -08:00
configure Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
configure.ac Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
COPYRIGHT Update copyright for 2025 2025-01-01 11:21:55 -05:00
GNUmakefile.in Allow selecting the git revision to be packaged by "make dist". 2024-05-03 11:08:50 -04:00
HISTORY Canonicalize some URLs 2020-02-10 20:47:50 +01:00
Makefile Remove AIX support 2024-02-28 15:17:23 +04:00
meson_options.txt Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
meson.build Make test portlock logic work with meson 2025-02-21 11:25:05 -05:00
README.md Revise the style of a paragraph in README.md. 2024-03-21 10:16:41 -05:00

PostgreSQL Database Management System

This directory contains the source code distribution of the PostgreSQL database management system.

PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.

Copyright and license information can be found in the file COPYRIGHT.

General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.

The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.