mirror of
				https://github.com/postgres/postgres.git
				synced 2025-11-03 09:13:20 +03:00 
			
		
		
		
	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
		
	
		
			
				
	
	
		
			33 lines
		
	
	
		
			999 B
		
	
	
	
		
			PL/PgSQL
		
	
	
	
	
	
			
		
		
	
	
			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;
 |