From 83e9c5bf761661068819f25ab91a6fd3c1297a27 Mon Sep 17 00:00:00 2001 From: "Chao Li (Evan)" Date: Tue, 30 Jun 2026 15:22:29 +0800 Subject: [PATCH v6] Fix RLS checks for FOR PORTION OF leftover rows UPDATE/DELETE FOR PORTION OF may insert leftover rows to preserve the parts of the old row that are outside the target range. Those inserts go through ExecInsert(), which checks RLS policies using WCO_RLS_INSERT_CHECK. However, the rewriter only added RLS WITH CHECK options for the original statement command. For UPDATE, that meant only WCO_RLS_UPDATE_CHECK options were available, so ExecInsert() skipped them. For DELETE, no RLS WITH CHECK options were added at all. As a result, leftover rows could be inserted even when they violated INSERT RLS policies. Fix this by adding INSERT RLS WITH CHECK options for UPDATE/DELETE FOR PORTION OF target relations. Also add regression coverage for both UPDATE and DELETE, including cases where allowed leftovers still succeed and disallowed leftovers are rejected. Author: Chao Li Co-authored-by: Paul A Jungwirth Reviewed-by: Paul A Jungwirth Reviewed-by: Ayush Tiwari Reviewed-by: Dean Rasheed Discussion: https://postgr.es/m/6C34A987-AC50-4477-BD71-2D4AFEE1A589@gmail.com Discussion: https://postgr.es/m/CAJTYsWWdeBkoH5g8D-k9LDw9ciqsMxb21EJSiFXAzP4J=XyxOQ@mail.gmail.com --- doc/src/sgml/ref/create_policy.sgml | 32 +++++++++ doc/src/sgml/ref/delete.sgml | 3 +- doc/src/sgml/ref/update.sgml | 3 +- src/backend/rewrite/rowsecurity.c | 25 +++++++ src/test/regress/expected/for_portion_of.out | 75 ++++++++++++++++++++ src/test/regress/expected/rowsecurity.out | 39 +++++++++- src/test/regress/sql/for_portion_of.sql | 58 +++++++++++++++ src/test/regress/sql/rowsecurity.sql | 33 ++++++++- 8 files changed, 264 insertions(+), 4 deletions(-) diff --git a/doc/src/sgml/ref/create_policy.sgml b/doc/src/sgml/ref/create_policy.sgml index d8a036739c0..0a1699185c9 100644 --- a/doc/src/sgml/ref/create_policy.sgml +++ b/doc/src/sgml/ref/create_policy.sgml @@ -530,6 +530,26 @@ CREATE POLICY name ON Check new row — + + UPDATE ... FOR PORTION OF + + Filter existing row & check new row + + + Check leftover rows  + + FOR PORTION OF re-inserts the portions of the + affected row that fall outside the targeted range, to preserve them. + These leftover rows are checked against the INSERT + policy's WITH CHECK expression, even though no + INSERT privilege is required to store them. + + + + Filter existing row + Check new row + — + DELETE @@ -540,6 +560,18 @@ CREATE POLICY name ON — Filter existing row + + DELETE ... FOR PORTION OF + + Filter existing row + + + Check leftover rows  + + — + — + Filter existing row + INSERT ... ON CONFLICT diff --git a/doc/src/sgml/ref/delete.sgml b/doc/src/sgml/ref/delete.sgml index ffdcd7fc4fa..3ab1f60525a 100644 --- a/doc/src/sgml/ref/delete.sgml +++ b/doc/src/sgml/ref/delete.sgml @@ -97,7 +97,8 @@ DELETE FROM [ ONLY ] table_name [ * When FOR PORTION OF is used, the secondary inserts do not require INSERT privilege on the table. (This is because conceptually no new information is being added; the inserted rows - only preserve existing data about the untargeted time period.) + only preserve existing data about the untargeted time period.) Row-level + security INSERT policies are still checked for these leftover inserts. diff --git a/doc/src/sgml/ref/update.sgml b/doc/src/sgml/ref/update.sgml index 21a8fd8b037..3175671d475 100644 --- a/doc/src/sgml/ref/update.sgml +++ b/doc/src/sgml/ref/update.sgml @@ -101,7 +101,8 @@ UPDATE [ ONLY ] table_name [ * ] When FOR PORTION OF is used, the secondary inserts do not require INSERT privilege on the table. (This is because conceptually no new information is being added; the inserted rows - only preserve existing data about the untargeted time period.) + only preserve existing data about the untargeted time period.) Row-level + security INSERT policies are still checked for these leftover inserts. diff --git a/src/backend/rewrite/rowsecurity.c b/src/backend/rewrite/rowsecurity.c index e88a1bc1a89..46d88f79894 100644 --- a/src/backend/rewrite/rowsecurity.c +++ b/src/backend/rewrite/rowsecurity.c @@ -393,6 +393,31 @@ get_row_security_policies(Query *root, RangeTblEntry *rte, int rt_index, } } + /* + * UPDATE/DELETE FOR PORTION OF may insert leftover rows to preserve the + * portions of the old row not covered by the target range. Those hidden + * inserts go through ExecInsert(), so they need the same INSERT RLS WITH + * CHECK options as ordinary INSERTs. SELECT rights are never needed for + * the leftover rows, because they are not considered by RETURNING. + */ + if (root->forPortionOf != NULL && rt_index == root->resultRelation && + (commandType == CMD_UPDATE || commandType == CMD_DELETE)) + { + List *insert_permissive_policies; + List *insert_restrictive_policies; + + get_policies_for_relation(rel, CMD_INSERT, user_id, + &insert_permissive_policies, + &insert_restrictive_policies); + add_with_check_options(rel, rt_index, + WCO_RLS_INSERT_CHECK, + insert_permissive_policies, + insert_restrictive_policies, + withCheckOptions, + hasSubLinks, + false); + } + /* * FOR MERGE, we fetch policies for UPDATE, DELETE and INSERT (and ALL) * and set them up so that we can enforce the appropriate policy depending diff --git a/src/test/regress/expected/for_portion_of.out b/src/test/regress/expected/for_portion_of.out index a050fc2dadf..271282c2d3b 100644 --- a/src/test/regress/expected/for_portion_of.out +++ b/src/test/regress/expected/for_portion_of.out @@ -2561,4 +2561,79 @@ SELECT * FROM fpo_cursed; (1 row) DROP TABLE fpo_cursed; +-- UPDATE/DELETE FOR PORTION OF leftover rows must satisfy RLS INSERT checks. +CREATE ROLE regress_fpo_rls; +CREATE TABLE fpo_rls ( + id int, + valid_at int4range +); +ALTER TABLE fpo_rls ENABLE ROW LEVEL SECURITY; +CREATE POLICY fpo_rls_select ON fpo_rls + FOR SELECT TO regress_fpo_rls + USING (true); +CREATE POLICY fpo_rls_update ON fpo_rls + FOR UPDATE TO regress_fpo_rls + USING (lower(valid_at) < 50) + WITH CHECK (lower(valid_at) < 50); +CREATE POLICY fpo_rls_delete ON fpo_rls + FOR DELETE TO regress_fpo_rls + USING (lower(valid_at) < 50); +CREATE POLICY fpo_rls_insert ON fpo_rls + FOR INSERT TO regress_fpo_rls + WITH CHECK (lower(valid_at) < 50); +GRANT SELECT, UPDATE, DELETE ON fpo_rls TO regress_fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +UPDATE fpo_rls + FOR PORTION OF valid_at FROM 30 TO 100 + SET id = 2; +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + id | valid_at +----+---------- + 1 | [10,30) + 2 | [30,100) +(2 rows) + +TRUNCATE fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +DELETE FROM fpo_rls + FOR PORTION OF valid_at FROM 30 TO 100; +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + id | valid_at +----+---------- + 1 | [10,30) +(1 row) + +TRUNCATE fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +UPDATE fpo_rls + FOR PORTION OF valid_at FROM 30 TO 70 + SET id = 2; +ERROR: new row violates row-level security policy for table "fpo_rls" +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + id | valid_at +----+---------- + 1 | [10,100) +(1 row) + +TRUNCATE fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +DELETE FROM fpo_rls + FOR PORTION OF valid_at FROM 30 TO 70; +ERROR: new row violates row-level security policy for table "fpo_rls" +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + id | valid_at +----+---------- + 1 | [10,100) +(1 row) + +DROP TABLE fpo_rls; +DROP ROLE regress_fpo_rls; RESET datestyle; diff --git a/src/test/regress/expected/rowsecurity.out b/src/test/regress/expected/rowsecurity.out index 3a5e82c35bd..f42085e53a0 100644 --- a/src/test/regress/expected/rowsecurity.out +++ b/src/test/regress/expected/rowsecurity.out @@ -68,6 +68,20 @@ CREATE POLICY upd_pol ON rls_test_tgt FOR UPDATE WITH CHECK (rls_test_policy_fn('UPDATE CHECK on rls_test_tgt', rls_test_tgt)); CREATE POLICY del_pol ON rls_test_tgt FOR DELETE USING (rls_test_policy_fn('DELETE USING on rls_test_tgt', rls_test_tgt)); +-- setup temporal target table (for FOR PORTION OF operations) +CREATE TABLE rls_test_fpo_tgt (a int, b text, valid_at int4range); +ALTER TABLE rls_test_fpo_tgt ENABLE ROW LEVEL SECURITY; +GRANT SELECT, UPDATE, DELETE ON rls_test_fpo_tgt TO public; +INSERT INTO rls_test_fpo_tgt VALUES (1, 'fpo a', '[1,10)'); +CREATE POLICY sel_pol ON rls_test_fpo_tgt FOR SELECT + USING (rls_test_policy_fn('SELECT USING on rls_test_fpo_tgt', rls_test_fpo_tgt)); +CREATE POLICY ins_pol ON rls_test_fpo_tgt FOR INSERT + WITH CHECK (rls_test_policy_fn('INSERT CHECK on rls_test_fpo_tgt', rls_test_fpo_tgt)); +CREATE POLICY upd_pol ON rls_test_fpo_tgt FOR UPDATE + USING (rls_test_policy_fn('UPDATE USING on rls_test_fpo_tgt', rls_test_fpo_tgt)) + WITH CHECK (rls_test_policy_fn('UPDATE CHECK on rls_test_fpo_tgt', rls_test_fpo_tgt)); +CREATE POLICY del_pol ON rls_test_fpo_tgt FOR DELETE + USING (rls_test_policy_fn('DELETE USING on rls_test_fpo_tgt', rls_test_fpo_tgt)); -- test policies applied to regress_rls_bob SET SESSION AUTHORIZATION regress_rls_bob; -- SELECT, COPY ... TO, and TABLE should only apply SELECT USING policy clause @@ -155,6 +169,19 @@ NOTICE: SELECT USING on rls_test_tgt.(1,"tgt d","TGT D") 1 | tgt d | TGT D (1 row) +-- UPDATE ... FOR PORTION OF should also apply SELECT USING policy clauses to +-- the old and new rows, and INSERT CHECK policy clauses to leftover rows. +BEGIN; +UPDATE rls_test_fpo_tgt + FOR PORTION OF valid_at FROM 3 TO 7 + SET b = 'fpo b'; +NOTICE: UPDATE USING on rls_test_fpo_tgt.(1,"fpo a","[1,10)") +NOTICE: SELECT USING on rls_test_fpo_tgt.(1,"fpo a","[1,10)") +NOTICE: UPDATE CHECK on rls_test_fpo_tgt.(1,"fpo b","[3,7)") +NOTICE: SELECT USING on rls_test_fpo_tgt.(1,"fpo b","[3,7)") +NOTICE: INSERT CHECK on rls_test_fpo_tgt.(1,"fpo a","[1,3)") +NOTICE: INSERT CHECK on rls_test_fpo_tgt.(1,"fpo a","[7,10)") +ROLLBACK; -- DELETE without WHERE or RETURNING should only apply DELETE USING policy clause BEGIN; DELETE FROM rls_test_tgt; ROLLBACK; NOTICE: DELETE USING on rls_test_tgt.(1,"tgt d","TGT D") @@ -170,6 +197,16 @@ NOTICE: SELECT USING on rls_test_tgt.(1,"tgt d","TGT D") 1 | tgt d | TGT D (1 row) +-- DELETE ... FOR PORTION OF should also apply SELECT USING policy clauses to +-- the old row, and INSERT CHECK policy clauses to leftover rows. +BEGIN; +DELETE FROM rls_test_fpo_tgt + FOR PORTION OF valid_at FROM 3 TO 7; +NOTICE: DELETE USING on rls_test_fpo_tgt.(1,"fpo a","[1,10)") +NOTICE: SELECT USING on rls_test_fpo_tgt.(1,"fpo a","[1,10)") +NOTICE: INSERT CHECK on rls_test_fpo_tgt.(1,"fpo a","[1,3)") +NOTICE: INSERT CHECK on rls_test_fpo_tgt.(1,"fpo a","[7,10)") +ROLLBACK; -- INSERT ... ON CONFLICT DO NOTHING with an arbiter clause should apply -- INSERT CHECK and SELECT USING policy clauses (to new value, whether it -- conflicts or not) @@ -332,7 +369,7 @@ NOTICE: DELETE USING on rls_test_tgt.(1,"tgt c","TGT C") -- Tidy up RESET SESSION AUTHORIZATION; -DROP TABLE rls_test_src, rls_test_tgt; +DROP TABLE rls_test_src, rls_test_tgt, rls_test_fpo_tgt; DROP FUNCTION rls_test_tgt_set_c; DROP FUNCTION rls_test_policy_fn; -- BASIC Row-Level Security Scenario diff --git a/src/test/regress/sql/for_portion_of.sql b/src/test/regress/sql/for_portion_of.sql index a1ee1d5e501..f48644347d1 100644 --- a/src/test/regress/sql/for_portion_of.sql +++ b/src/test/regress/sql/for_portion_of.sql @@ -1676,4 +1676,62 @@ ROLLBACK; SELECT * FROM fpo_cursed; DROP TABLE fpo_cursed; +-- UPDATE/DELETE FOR PORTION OF leftover rows must satisfy RLS INSERT checks. +CREATE ROLE regress_fpo_rls; +CREATE TABLE fpo_rls ( + id int, + valid_at int4range +); +ALTER TABLE fpo_rls ENABLE ROW LEVEL SECURITY; +CREATE POLICY fpo_rls_select ON fpo_rls + FOR SELECT TO regress_fpo_rls + USING (true); +CREATE POLICY fpo_rls_update ON fpo_rls + FOR UPDATE TO regress_fpo_rls + USING (lower(valid_at) < 50) + WITH CHECK (lower(valid_at) < 50); +CREATE POLICY fpo_rls_delete ON fpo_rls + FOR DELETE TO regress_fpo_rls + USING (lower(valid_at) < 50); +CREATE POLICY fpo_rls_insert ON fpo_rls + FOR INSERT TO regress_fpo_rls + WITH CHECK (lower(valid_at) < 50); +GRANT SELECT, UPDATE, DELETE ON fpo_rls TO regress_fpo_rls; + +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +UPDATE fpo_rls + FOR PORTION OF valid_at FROM 30 TO 100 + SET id = 2; +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + +TRUNCATE fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +DELETE FROM fpo_rls + FOR PORTION OF valid_at FROM 30 TO 100; +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + +TRUNCATE fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +UPDATE fpo_rls + FOR PORTION OF valid_at FROM 30 TO 70 + SET id = 2; +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + +TRUNCATE fpo_rls; +INSERT INTO fpo_rls VALUES (1, '[10,100)'); +SET ROLE regress_fpo_rls; +DELETE FROM fpo_rls + FOR PORTION OF valid_at FROM 30 TO 70; +RESET ROLE; +SELECT * FROM fpo_rls ORDER BY valid_at; + +DROP TABLE fpo_rls; +DROP ROLE regress_fpo_rls; + RESET datestyle; diff --git a/src/test/regress/sql/rowsecurity.sql b/src/test/regress/sql/rowsecurity.sql index 6b3566271df..0bd24d1028b 100644 --- a/src/test/regress/sql/rowsecurity.sql +++ b/src/test/regress/sql/rowsecurity.sql @@ -85,6 +85,22 @@ CREATE POLICY upd_pol ON rls_test_tgt FOR UPDATE CREATE POLICY del_pol ON rls_test_tgt FOR DELETE USING (rls_test_policy_fn('DELETE USING on rls_test_tgt', rls_test_tgt)); +-- setup temporal target table (for FOR PORTION OF operations) +CREATE TABLE rls_test_fpo_tgt (a int, b text, valid_at int4range); +ALTER TABLE rls_test_fpo_tgt ENABLE ROW LEVEL SECURITY; +GRANT SELECT, UPDATE, DELETE ON rls_test_fpo_tgt TO public; +INSERT INTO rls_test_fpo_tgt VALUES (1, 'fpo a', '[1,10)'); + +CREATE POLICY sel_pol ON rls_test_fpo_tgt FOR SELECT + USING (rls_test_policy_fn('SELECT USING on rls_test_fpo_tgt', rls_test_fpo_tgt)); +CREATE POLICY ins_pol ON rls_test_fpo_tgt FOR INSERT + WITH CHECK (rls_test_policy_fn('INSERT CHECK on rls_test_fpo_tgt', rls_test_fpo_tgt)); +CREATE POLICY upd_pol ON rls_test_fpo_tgt FOR UPDATE + USING (rls_test_policy_fn('UPDATE USING on rls_test_fpo_tgt', rls_test_fpo_tgt)) + WITH CHECK (rls_test_policy_fn('UPDATE CHECK on rls_test_fpo_tgt', rls_test_fpo_tgt)); +CREATE POLICY del_pol ON rls_test_fpo_tgt FOR DELETE + USING (rls_test_policy_fn('DELETE USING on rls_test_fpo_tgt', rls_test_fpo_tgt)); + -- test policies applied to regress_rls_bob SET SESSION AUTHORIZATION regress_rls_bob; @@ -114,6 +130,14 @@ UPDATE rls_test_tgt SET b = 'tgt b'; UPDATE rls_test_tgt SET b = 'tgt c' WHERE a = 1; UPDATE rls_test_tgt SET b = 'tgt d' RETURNING *; +-- UPDATE ... FOR PORTION OF should also apply SELECT USING policy clauses to +-- the old and new rows, and INSERT CHECK policy clauses to leftover rows. +BEGIN; +UPDATE rls_test_fpo_tgt + FOR PORTION OF valid_at FROM 3 TO 7 + SET b = 'fpo b'; +ROLLBACK; + -- DELETE without WHERE or RETURNING should only apply DELETE USING policy clause BEGIN; DELETE FROM rls_test_tgt; ROLLBACK; @@ -121,6 +145,13 @@ BEGIN; DELETE FROM rls_test_tgt; ROLLBACK; BEGIN; DELETE FROM rls_test_tgt WHERE a = 1; ROLLBACK; DELETE FROM rls_test_tgt RETURNING *; +-- DELETE ... FOR PORTION OF should also apply SELECT USING policy clauses to +-- the old row, and INSERT CHECK policy clauses to leftover rows. +BEGIN; +DELETE FROM rls_test_fpo_tgt + FOR PORTION OF valid_at FROM 3 TO 7; +ROLLBACK; + -- INSERT ... ON CONFLICT DO NOTHING with an arbiter clause should apply -- INSERT CHECK and SELECT USING policy clauses (to new value, whether it -- conflicts or not) @@ -192,7 +223,7 @@ MERGE INTO rls_test_tgt t USING rls_test_src s ON t.a = s.a -- Tidy up RESET SESSION AUTHORIZATION; -DROP TABLE rls_test_src, rls_test_tgt; +DROP TABLE rls_test_src, rls_test_tgt, rls_test_fpo_tgt; DROP FUNCTION rls_test_tgt_set_c; DROP FUNCTION rls_test_policy_fn; -- 2.50.1 (Apple Git-155)