From b00f342ea0f01c3964491108dc4428838ffc269e Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 3 Nov 2022 12:01:57 -0400 Subject: [PATCH] Avoid crash after function syntax error in a replication worker. If a syntax error occurred in a SQL-language or PL/pgSQL-language CREATE FUNCTION or DO command executed in a logical replication worker, we'd suffer a null pointer dereference or assertion failure. That seems like a rather contrived case, but nonetheless worth fixing. The cause is that function_parse_error_transpose assumes it must be executing within the context of a Portal, but logical/worker.c doesn't create a Portal since it's not running the standard executor. We can just back off the hard Assert check and make it fail gracefully if there's not an ActivePortal. (I have a feeling that the aggressive check here was my fault originally, probably because I wasn't sure if the case would always hold and wanted to find out. Well, now we know.) The hazard seems to exist in all branches that have logical replication, so back-patch to v10. Maxim Orlov, Anton Melnikov, Masahiko Sawada, Tom Lane Discussion: https://postgr.es/m/b570c367-ba38-95f3-f62d-5f59b9808226@inbox.ru Discussion: https://postgr.es/m/adf0452f-8c6b-7def-d35e-ab516c80088e@inbox.ru --- src/backend/catalog/pg_proc.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/src/backend/catalog/pg_proc.c b/src/backend/catalog/pg_proc.c index 7c0a18d004..3041b443d6 100644 --- a/src/backend/catalog/pg_proc.c +++ b/src/backend/catalog/pg_proc.c @@ -971,7 +971,6 @@ function_parse_error_transpose(const char *prosrc) { int origerrposition; int newerrposition; - const char *queryText; /* * Nothing to do unless we are dealing with a syntax error that has a @@ -989,11 +988,22 @@ function_parse_error_transpose(const char *prosrc) } /* We can get the original query text from the active portal (hack...) */ - Assert(ActivePortal && ActivePortal->status == PORTAL_ACTIVE); - queryText = ActivePortal->sourceText; + if (ActivePortal && ActivePortal->status == PORTAL_ACTIVE) + { + const char *queryText = ActivePortal->sourceText; - /* Try to locate the prosrc in the original text */ - newerrposition = match_prosrc_to_query(prosrc, queryText, origerrposition); + /* Try to locate the prosrc in the original text */ + newerrposition = match_prosrc_to_query(prosrc, queryText, + origerrposition); + } + else + { + /* + * Quietly give up if no ActivePortal. This is an unusual situation + * but it can happen in, e.g., logical replication workers. + */ + newerrposition = -1; + } if (newerrposition > 0) {