From a316a3bc6d3f57e3fe0d287d11eb4f114388b1b6 Mon Sep 17 00:00:00 2001 From: Alvaro Herrera Date: Mon, 20 Feb 2023 16:00:42 +0100 Subject: [PATCH] Correctly set userid of subquery relations' child rels The RelOptInfo->userid field (the user ID to check permissions as) of an "otherrel" relation was being copied from its parent relation, which is correct in most cases but wrong when the parent is a subquery. In that case, using the value from the RTEPermissionInfo of the child itself is the appropriate thing to do. Coming up with a test case where user-visible behavior changes proves hard enough, so we don't add one here. Bug introduced by a61b1f74823c, discovered by Amit while reviewing nearby code. Author: Amit Langote Discussion: https://postgr.es/m/CA+HiwqE0WY_AhLnGtTsY7eYebG212XWbM-D8gr2A_ToOHyCywQ@mail.gmail.com --- src/backend/optimizer/util/relnode.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/src/backend/optimizer/util/relnode.c b/src/backend/optimizer/util/relnode.c index a70a16238a..d29a25f8aa 100644 --- a/src/backend/optimizer/util/relnode.c +++ b/src/backend/optimizer/util/relnode.c @@ -233,12 +233,22 @@ build_simple_rel(PlannerInfo *root, int relid, RelOptInfo *parent) rel->serverid = InvalidOid; if (rte->rtekind == RTE_RELATION) { + Assert(parent == NULL || + parent->rtekind == RTE_RELATION || + parent->rtekind == RTE_SUBQUERY); + /* - * Get the userid from the relation's RTEPermissionInfo, though only - * the tables mentioned in query are assigned RTEPermissionInfos. - * Child relations (otherrels) simply use the parent's value. + * For any RELATION rte, we need a userid with which to check + * permission access. Baserels simply use their own + * RTEPermissionInfo's checkAsUser. + * + * For otherrels normally there's no RTEPermissionInfo, so we use the + * parent's, which normally has one. The exceptional case is that the + * parent is a subquery, in which case the otherrel will have its own. */ - if (parent == NULL) + if (rel->reloptkind == RELOPT_BASEREL || + (rel->reloptkind == RELOPT_OTHER_MEMBER_REL && + parent->rtekind == RTE_SUBQUERY)) { RTEPermissionInfo *perminfo; -- 2.30.2