postgresql/contrib/seg/sql/security.sql
Noah Misch dbd5795e75 Replace last PushOverrideSearchPath() call with set_config_option().
The two methods don't cooperate, so set_config_option("search_path",
...) has been ineffective under non-empty overrideStack.  This defect
enabled an attacker having database-level CREATE privilege to execute
arbitrary code as the bootstrap superuser.  While that particular attack
requires v13+ for the trusted extension attribute, other attacks are
feasible in all supported versions.

Standardize on the combination of NewGUCNestLevel() and
set_config_option("search_path", ...).  It is newer than
PushOverrideSearchPath(), more-prevalent, and has no known
disadvantages.  The "override" mechanism remains for now, for
compatibility with out-of-tree code.  Users should update such code,
which likely suffers from the same sort of vulnerability closed here.
Back-patch to v11 (all supported versions).

Alexander Lakhin.  Reported by Alexander Lakhin.

Security: CVE-2023-2454
2023-05-08 06:14:11 -07:00

33 lines
999 B
PL/PgSQL

--
-- Test extension script protection against search path overriding
--
CREATE ROLE regress_seg_role;
SELECT current_database() AS datname \gset
GRANT CREATE ON DATABASE :"datname" TO regress_seg_role;
SET ROLE regress_seg_role;
CREATE SCHEMA regress_seg_schema;
CREATE FUNCTION regress_seg_schema.exfun(i int) RETURNS int AS $$
BEGIN
CREATE EXTENSION seg VERSION '1.2';
CREATE FUNCTION regress_seg_schema.compare(oid, regclass) RETURNS boolean AS
'BEGIN RAISE EXCEPTION ''overloaded compare() called by %'', current_user; END;' LANGUAGE plpgsql;
CREATE OPERATOR = (LEFTARG = oid, RIGHTARG = regclass, PROCEDURE = regress_seg_schema.compare);
ALTER EXTENSION seg UPDATE TO '1.3';
RETURN i;
END; $$ LANGUAGE plpgsql;
CREATE SCHEMA test_schema
CREATE TABLE t(i int) PARTITION BY RANGE (i)
CREATE TABLE p1 PARTITION OF t FOR VALUES FROM (1) TO (regress_seg_schema.exfun(2));
DROP SCHEMA test_schema CASCADE;
RESET ROLE;
DROP OWNED BY regress_seg_role;
DROP ROLE regress_seg_role;