From fff2a7d7bd09db38e1bafc1303c29b10a9805dc0 Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Mon, 10 Jun 2019 23:20:48 -0700 Subject: Don't access catalogs to validate GUCs when not connected to a DB. Vignesh found this bug in the check function for default_table_access_method's check hook, but that was just copied from older GUCs. Investigation by Michael and me then found the bug in further places. When not connected to a database (e.g. in a walsender connection), we cannot perform (most) GUC checks that need database access. Even when only shared tables are needed, unless they're nailed (c.f. RelationCacheInitializePhase2()), they cannot be accessed without pg_class etc. being present. Fix by extending the existing IsTransactionState() checks to also check for MyDatabaseOid. Reported-By: Vignesh C, Michael Paquier, Andres Freund Author: Vignesh C, Andres Freund Discussion: https://postgr.es/m/CALDaNm1KXK9gbZfY-p_peRFm_XrBh1OwQO1Kk6Gig0c0fVZ2uw%40mail.gmail.com Backpatch: 9.4- --- src/backend/access/table/tableamapi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'src/backend/access/table/tableamapi.c') diff --git a/src/backend/access/table/tableamapi.c b/src/backend/access/table/tableamapi.c index 34e6a4f20de..fdd7e64ada8 100644 --- a/src/backend/access/table/tableamapi.c +++ b/src/backend/access/table/tableamapi.c @@ -18,6 +18,7 @@ #include "catalog/pg_am.h" #include "catalog/pg_proc.h" #include "commands/defrem.h" +#include "miscadmin.h" #include "utils/fmgroids.h" #include "utils/memutils.h" #include "utils/syscache.h" @@ -119,10 +120,11 @@ check_default_table_access_method(char **newval, void **extra, GucSource source) } /* - * If we aren't inside a transaction, we cannot do database access so - * cannot verify the name. Must accept the value on faith. + * If we aren't inside a transaction, or not connected to a database, we + * cannot do the catalog access necessary to verify the method. Must + * accept the value on faith. */ - if (IsTransactionState()) + if (IsTransactionState() && MyDatabaseId != InvalidOid) { if (!OidIsValid(get_table_am_oid(*newval, true))) { -- cgit v1.2.3