Fix "unexpected relkind" error when denying permissions on toast tables.

get_relkind_objtype, and hence get_object_type, failed when applied to a
toast table.  This is not a good thing, because it prevents reporting of
perfectly legitimate permissions errors.  (At present, these functions
are in fact *only* used to determine the ObjectType argument for
acl_error() calls.)  It seems best to have them fall back to returning
OBJECT_TABLE in every case where they can't determine an object type
for a pg_class entry, so do that.

In passing, make some edits to alter.c to make it more obvious that
those calls of get_object_type() are used only for error reporting.
This might save a few cycles in the non-error code path, too.

Back-patch to v11 where this issue originated.

John Hsu, Michael Paquier, Tom Lane

Discussion: https://postgr.es/m/C652D3DF-2B0C-4128-9420-FB5379F6B1E4@amazon.com

diff --git a/src/backend/catalog/objectaddress.c b/src/backend/catalog/objectaddress.c
index f5c647a86459c0f09690bd94cc09ce0546525c2a..8f6e8f05e03e85d919b6bbd73f155adb3e08714f 100644 (file)
--- a/src/backend/catalog/objectaddress.c
+++ b/src/backend/catalog/objectaddress.c
@@ -2564,6 +2564,13 @@ get_object_attnum_acl(Oid class_id)
    return prop->attnum_acl;
 }
 
+/*
+ * get_object_type
+ *
+ * Return the object type associated with a given object.  This routine
+ * is primarily used to determine the object type to mention in ACL check
+ * error messages, so it's desirable for it to avoid failing.
+ */
 ObjectType
 get_object_type(Oid class_id, Oid object_id)
 {
@@ -5274,6 +5281,16 @@ strlist_to_textarray(List *list)
    return arr;
 }
 
+/*
+ * get_relkind_objtype
+ *
+ * Return the object type for the relkind given by the caller.
+ *
+ * If an unexpected relkind is passed, we say OBJECT_TABLE rather than
+ * failing.  That's because this is mostly used for generating error messages
+ * for failed ACL checks on relations, and we'd rather produce a generic
+ * message saying "table" than fail entirely.
+ */
 ObjectType
 get_relkind_objtype(char relkind)
 {
@@ -5293,13 +5310,10 @@ get_relkind_objtype(char relkind)
            return OBJECT_MATVIEW;
        case RELKIND_FOREIGN_TABLE:
            return OBJECT_FOREIGN_TABLE;
-
-           /*
-            * other relkinds are not supported here because they don't map to
-            * OBJECT_* values
-            */
+       case RELKIND_TOASTVALUE:
+           return OBJECT_TABLE;
        default:
-           elog(ERROR, "unexpected relkind: %d", relkind);
-           return 0;
+           /* Per above, don't raise an error */
+           return OBJECT_TABLE;
    }
 }

diff --git a/src/backend/commands/alter.c b/src/backend/commands/alter.c
index eff325cc7d00286c7259d0cbc688f3a6c4cf5ae3..4d443c13292c9559395cd28306378575e194c3c7 100644 (file)
--- a/src/backend/commands/alter.c
+++ b/src/backend/commands/alter.c
@@ -171,7 +171,6 @@ AlterObjectRename_internal(Relation rel, Oid objectId, const char *new_name)
    AttrNumber  Anum_name = get_object_attnum_name(classId);
    AttrNumber  Anum_namespace = get_object_attnum_namespace(classId);
    AttrNumber  Anum_owner = get_object_attnum_owner(classId);
-   ObjectType  objtype = get_object_type(classId, objectId);
    HeapTuple   oldtup;
    HeapTuple   newtup;
    Datum       datum;
@@ -223,7 +222,8 @@ AlterObjectRename_internal(Relation rel, Oid objectId, const char *new_name)
        ownerId = DatumGetObjectId(datum);
 
        if (!has_privs_of_role(GetUserId(), DatumGetObjectId(ownerId)))
-           aclcheck_error(ACLCHECK_NOT_OWNER, objtype, old_name);
+           aclcheck_error(ACLCHECK_NOT_OWNER, get_object_type(classId, objectId),
+                          old_name);
 
        /* User must have CREATE privilege on the namespace */
        if (OidIsValid(namespaceId))
@@ -663,7 +663,6 @@ AlterObjectNamespace_internal(Relation rel, Oid objid, Oid nspOid)
    AttrNumber  Anum_name = get_object_attnum_name(classId);
    AttrNumber  Anum_namespace = get_object_attnum_namespace(classId);
    AttrNumber  Anum_owner = get_object_attnum_owner(classId);
-   ObjectType  objtype = get_object_type(classId, objid);
    Oid         oldNspOid;
    Datum       name,
                namespace;
@@ -719,7 +718,7 @@ AlterObjectNamespace_internal(Relation rel, Oid objid, Oid nspOid)
        ownerId = DatumGetObjectId(owner);
 
        if (!has_privs_of_role(GetUserId(), ownerId))
-           aclcheck_error(ACLCHECK_NOT_OWNER, objtype,
+           aclcheck_error(ACLCHECK_NOT_OWNER, get_object_type(classId, objid),
                           NameStr(*(DatumGetName(name))));
 
        /* User must have CREATE privilege on new namespace */
@@ -942,8 +941,6 @@ AlterObjectOwner_internal(Relation rel, Oid objectId, Oid new_ownerId)
        /* Superusers can bypass permission checks */
        if (!superuser())
        {
-           ObjectType  objtype = get_object_type(classId, objectId);
-
            /* must be owner */
            if (!has_privs_of_role(GetUserId(), old_ownerId))
            {
@@ -963,7 +960,8 @@ AlterObjectOwner_internal(Relation rel, Oid objectId, Oid new_ownerId)
                             HeapTupleGetOid(oldtup));
                    objname = namebuf;
                }
-               aclcheck_error(ACLCHECK_NOT_OWNER, objtype, objname);
+               aclcheck_error(ACLCHECK_NOT_OWNER, get_object_type(classId, objectId),
+                              objname);
            }
            /* Must be able to become new owner */
            check_is_member_of_role(GetUserId(), new_ownerId);

diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out
index be25101db24cbbc673aec6230e436dcf44eca5d8..90b671f5b91d4f15399e736aba1c41fd8173ad42 100644 (file)
--- a/src/test/regress/expected/create_index.out
+++ b/src/test/regress/expected/create_index.out
@@ -3134,8 +3134,17 @@ CREATE ROLE regress_reindexuser NOLOGIN;
 SET SESSION ROLE regress_reindexuser;
 REINDEX SCHEMA schema_to_reindex;
 ERROR:  must be owner of schema schema_to_reindex
+-- Permission failures with toast tables and indexes (pg_proc's toast here)
+RESET ROLE;
+GRANT USAGE ON SCHEMA pg_toast TO regress_reindexuser;
+SET SESSION ROLE regress_reindexuser;
+REINDEX TABLE pg_toast.pg_toast_1255;
+ERROR:  must be owner of table pg_toast_1255
+REINDEX INDEX pg_toast.pg_toast_1255_index;
+ERROR:  must be owner of index pg_toast_1255_index
 -- Clean up
 RESET ROLE;
+REVOKE USAGE ON SCHEMA pg_toast FROM regress_reindexuser;
 DROP ROLE regress_reindexuser;
 \set VERBOSITY terse \\ -- suppress cascade details
 DROP SCHEMA schema_to_reindex CASCADE;

diff --git a/src/test/regress/sql/create_index.sql b/src/test/regress/sql/create_index.sql
index f9e7118f0d3d864325de765f83e6015f90bbd778..6eee92bf973ca0543dc92b0ee67202dcc9478bee 100644 (file)
--- a/src/test/regress/sql/create_index.sql
+++ b/src/test/regress/sql/create_index.sql
@@ -1126,9 +1126,16 @@ END;
 CREATE ROLE regress_reindexuser NOLOGIN;
 SET SESSION ROLE regress_reindexuser;
 REINDEX SCHEMA schema_to_reindex;
+-- Permission failures with toast tables and indexes (pg_proc's toast here)
+RESET ROLE;
+GRANT USAGE ON SCHEMA pg_toast TO regress_reindexuser;
+SET SESSION ROLE regress_reindexuser;
+REINDEX TABLE pg_toast.pg_toast_1255;
+REINDEX INDEX pg_toast.pg_toast_1255_index;
 
 -- Clean up
 RESET ROLE;
+REVOKE USAGE ON SCHEMA pg_toast FROM regress_reindexuser;
 DROP ROLE regress_reindexuser;
 \set VERBOSITY terse \\ -- suppress cascade details
 DROP SCHEMA schema_to_reindex CASCADE;