mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2024-12-09 08:10:09 +08:00
Code Issues Packages Projects Releases Wiki Activity

Guard against table-AM-less relations in planner.

Browse Source 
The executor will dump core if it's asked to execute a seqscan on
a relation having no table AM, such as a view.  While that shouldn't
really happen, it's possible to get there via catalog corruption,
such as a missing ON SELECT rule.  It seems worth installing a defense
against that.  There are multiple plausible places for such a defense,
but I picked the planner's get_relation_info().

Per discussion of bug #17646 from Kui Liu.  Back-patch to v12 where
the tableam APIs were introduced; in older versions you won't get a
SIGSEGV, so it seems less pressing.

Discussion: https://postgr.es/m/17646-70c93cfa40365776@postgresql.org
This commit is contained in:
Tom Lane 2022-10-17 11:35:23 -04:00
parent c68a183990
commit eec3466118
1 changed files with 18 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
src/backend/optimizer/util/plancat.c
View File

@ -127,6 +127,24 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
*/
relation = table_open(relationObjectId, NoLock);
/*
* Relations without a table AM can be used in a query only if they are of
* special-cased relkinds. This check prevents us from crashing later if,
* for example, a view's ON SELECT rule has gone missing. Note that
* table_open() already rejected indexes and composite types; spell the
* error the same way it does.
*/
if (!relation->rd_tableam)
{
if (!(relation->rd_rel->relkind == RELKIND_FOREIGN_TABLE ||
relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("cannot open relation \"%s\"",
RelationGetRelationName(relation)),
errdetail_relkind_not_supported(relation->rd_rel->relkind)));
}
/* Temporary and unlogged relations are inaccessible during recovery. */
if (!RelationIsPermanent(relation) && RecoveryInProgress())
ereport(ERROR,