b46efe9048
While pgoutput caches relation synchronization information in RelationSyncCache that resides in CacheMemoryContext, each entry's information (such as row filter expressions and column lists) is stored in the entry's private memory context (entry_cxt in RelationSyncEntry), which is a descendant memory context of the decoding context. If a logical decoding invoked via SQL functions like pg_logical_slot_get_binary_changes fails with an error, subsequent logical decoding executions could access already-freed memory of the entry's cache, resulting in a crash. With this change, it's ensured that RelationSyncCache is cleaned up even in error cases by using a memory context reset callback function. Backpatch to 15, where entry_cxt was introduced for column filtering and row filtering. While the backbranches v13 and v14 have a similar issue where RelationSyncCache persists even after an error when pgoutput is used via SQL API, we decided not to backport this fix. This decision was made because v13 is approaching its final minor release, and we won't have an chance to fix any new issues that might arise. Additionally, since using pgoutput via SQL API is not a common use case, the risk outwights the benefit. If we receive bug reports, we can consider backporting the fixes then. Author: vignesh C <vignesh21@gmail.com> Co-authored-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com> Reviewed-by: Euler Taveira <euler@eulerto.com> Discussion: https://postgr.es/m/CALDaNm0x-aCehgt8Bevs2cm=uhmwS28MvbYq1=s2Ekf0aDPkOA@mail.gmail.com Backpatch-through: 15
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/.