amcheck: Sanitize metapage's allequalimage field.
This will be helpful if it ever proves necessary to revoke an opclass's
support for deduplication.
Backpatch: 13-, where nbtree deduplication was introduced.
@@ -305,8 +305,20 @@ bt_index_check_internal(Oid indrelid, bool parentcheck, bool heapallindexed,
errmsg("index \"%s\" lacks a main relation fork",
RelationGetRelationName(indrel))));
- /* Check index, possibly against table it is an index on */
+ /* Extract metadata from metapage, and sanitize it in passing */
_bt_metaversion(indrel, &heapkeyspace, &allequalimage);
+ if (allequalimage && !heapkeyspace)
+ ereport(ERROR,
+ (errcode(ERRCODE_INDEX_CORRUPTED),
+ errmsg("index \"%s\" metapage has equalimage field set on unsupported nbtree version",
+ RelationGetRelationName(indrel))));
+ if (allequalimage && !_bt_allequalimage(indrel, false))
+ ereport(ERROR,
+ (errcode(ERRCODE_INDEX_CORRUPTED),
+ errmsg("index \"%s\" metapage incorrectly indicates that deduplication is safe",
+ RelationGetRelationName(indrel))));
+
+ /* Check index, possibly against table it is an index on */
bt_check_every_level(indrel, heaprel, heapkeyspace, parentcheck,
heapallindexed, rootdescend);
}
