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Commit 25936fd46 adjusted things so that the "storeslot" we use for remapping trigger tuples would have adequate lifespan, but it neglected to consider the lifespan of the tuple descriptor that the slot depends on. It turns out that in at least some cases, the tupdesc we are passing is a refcounted tupdesc, and the refcount for the slot's reference can get assigned to a resource owner having different lifespan than the slot does. That leads to an error like "tupdesc reference 0x7fdef236a1b8 is not owned by resource owner SubTransaction". Worse, because of a second oversight in the same commit, we'd try to free the same tupdesc refcount again while cleaning up after that error, leading to recursive errors and an "ERRORDATA_STACK_SIZE exceeded" PANIC. To fix the initial problem, let's just make a non-refcounted copy of the tupdesc we're supposed to use. That seems likely to guard against additional problems, since there's no strong reason for this code to assume that what it's given is a refcounted tupdesc; in which case there's an independent hazard of the tupdesc having shorter lifespan than the slot does. (I didn't bother trying to free said copy, since it should go away anyway when the (sub) transaction context is cleaned up.) The other issue can be fixed by making the code added to AfterTriggerFreeQuery work like the rest of that function, ie be sure that it doesn't try to free the same slot twice in the event of recursive error cleanup. While here, also clean up minor stylistic issues in the test case added by 25936fd46: don't use "create or replace function", as any name collision within the tests is likely to have ill effects that that won't mask; and don't use function names as generic as trigger_function1, especially if you're not going to drop them at the end of the test stanza. Per bug #17607 from Thomas Mc Kay. Back-patch to v12, as the previous fix was. Discussion: https://postgr.es/m/17607-bd8ccc81226f7f80@postgresql.org
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. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.