Fix ALTER DEFAULT PRIVILEGES with duplicated objects

Specifying duplicated objects in this command would lead to unique
constraint violations in pg_default_acl or "tuple already updated by
self" errors.  Similarly to GRANT/REVOKE, increment the command ID after
each subcommand processing to allow this case to work transparently.

A regression test is added by tweaking one of the existing queries of
privileges.sql to stress this case.

Reported-by: Andrus
Author: Michael Paquier
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/ae2a7dc1-9d71-8cba-3bb9-e4cb7eb1f44e@hot.ee
Backpatch-through: 9.5

diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index 9c8711ed0509b795839861a3b6cde6ae62c6bb43..63ea8f11f4478f30db2cae0ef858f3498c9b32ab 100644 (file)
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -1312,6 +1312,9 @@ SetDefaultACL(InternalDefaultACL *iacls)
        ReleaseSysCache(tuple);
 
    heap_close(rel, RowExclusiveLock);
+
+   /* prevent error when processing duplicate objects */
+   CommandCounterIncrement();
 }
 
 

diff --git a/src/test/regress/expected/privileges.out b/src/test/regress/expected/privileges.out
index 14ce823ffc736d9e53028f9ebebcb82dd060567e..adc9c9b5b60db302d63ad6818cecc02282c144e0 100644 (file)
--- a/src/test/regress/expected/privileges.out
+++ b/src/test/regress/expected/privileges.out
@@ -1562,7 +1562,8 @@ SELECT has_table_privilege('regress_user1', 'testns.acltest1', 'INSERT'); -- no
  f
 (1 row)
 
-ALTER DEFAULT PRIVILEGES IN SCHEMA testns GRANT SELECT ON TABLES TO public;
+-- placeholder for test with duplicated schema and role names
+ALTER DEFAULT PRIVILEGES IN SCHEMA testns,testns GRANT SELECT ON TABLES TO public,public;
 SELECT has_table_privilege('regress_user1', 'testns.acltest1', 'SELECT'); -- no
  has_table_privilege 
 ---------------------

diff --git a/src/test/regress/sql/privileges.sql b/src/test/regress/sql/privileges.sql
index f1d879c0873397e450c12c0120fa7edd1ba1b085..ff3ed02415f9f237da2591f6eaebb099eded6498 100644 (file)
--- a/src/test/regress/sql/privileges.sql
+++ b/src/test/regress/sql/privileges.sql
@@ -933,7 +933,8 @@ CREATE TABLE testns.acltest1 (x int);
 SELECT has_table_privilege('regress_user1', 'testns.acltest1', 'SELECT'); -- no
 SELECT has_table_privilege('regress_user1', 'testns.acltest1', 'INSERT'); -- no
 
-ALTER DEFAULT PRIVILEGES IN SCHEMA testns GRANT SELECT ON TABLES TO public;
+-- placeholder for test with duplicated schema and role names
+ALTER DEFAULT PRIVILEGES IN SCHEMA testns,testns GRANT SELECT ON TABLES TO public,public;
 
 SELECT has_table_privilege('regress_user1', 'testns.acltest1', 'SELECT'); -- no
 SELECT has_table_privilege('regress_user1', 'testns.acltest1', 'INSERT'); -- no