From e415b469b33ba328765e39fd62edcd28f30d9c3c Mon Sep 17 00:00:00 2001 From: Noah Misch Date: Wed, 7 Jan 2015 22:33:58 -0500 Subject: [PATCH] Reject ANALYZE commands during VACUUM FULL or another ANALYZE. vacuum()'s static variable handling makes it non-reentrant; an ensuing null pointer deference crashed the backend. Back-patch to 9.0 (all supported versions). --- src/backend/commands/vacuum.c | 14 ++++++++++++-- src/test/regress/expected/vacuum.out | 14 +++++++++++++- src/test/regress/sql/vacuum.sql | 9 ++++++++- 3 files changed, 33 insertions(+), 4 deletions(-) diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c index a787e8071f..2f3f79d87d 100644 --- a/src/backend/commands/vacuum.c +++ b/src/backend/commands/vacuum.c @@ -105,6 +105,7 @@ vacuum(VacuumStmt *vacstmt, Oid relid, bool do_toast, volatile bool in_outer_xact, use_own_xacts; List *relations; + static bool in_vacuum = false; /* sanity checks on options */ Assert(vacstmt->options & (VACOPT_VACUUM | VACOPT_ANALYZE)); @@ -130,6 +131,14 @@ vacuum(VacuumStmt *vacstmt, Oid relid, bool do_toast, else in_outer_xact = IsInTransactionChain(isTopLevel); + /* + * Due to static variables vac_context, anl_context and vac_strategy, + * vacuum() is not reentrant. This matters when VACUUM FULL or ANALYZE + * calls a hostile index expression that itself calls ANALYZE. + */ + if (in_vacuum) + elog(ERROR, "%s cannot be executed from VACUUM or ANALYZE", stmttype); + /* * Send info about dead objects to the statistics collector, unless we are * in autovacuum --- autovacuum.c does this for itself. @@ -222,6 +231,7 @@ vacuum(VacuumStmt *vacstmt, Oid relid, bool do_toast, { ListCell *cur; + in_vacuum = true; VacuumCostActive = (VacuumCostDelay > 0); VacuumCostBalance = 0; VacuumPageHit = 0; @@ -266,13 +276,13 @@ vacuum(VacuumStmt *vacstmt, Oid relid, bool do_toast, } PG_CATCH(); { - /* Make sure cost accounting is turned off after error */ + in_vacuum = false; VacuumCostActive = false; PG_RE_THROW(); } PG_END_TRY(); - /* Turn off vacuum cost accounting */ + in_vacuum = false; VacuumCostActive = false; /* diff --git a/src/test/regress/expected/vacuum.out b/src/test/regress/expected/vacuum.out index 190043c255..4f2f5e228f 100644 --- a/src/test/regress/expected/vacuum.out +++ b/src/test/regress/expected/vacuum.out @@ -60,12 +60,24 @@ VACUUM (FULL, FREEZE) vactst; VACUUM (ANALYZE, FULL) vactst; CREATE TABLE vaccluster (i INT PRIMARY KEY); ALTER TABLE vaccluster CLUSTER ON vaccluster_pkey; -INSERT INTO vaccluster SELECT * FROM vactst; CLUSTER vaccluster; +CREATE FUNCTION do_analyze() RETURNS VOID VOLATILE LANGUAGE SQL + AS 'ANALYZE pg_am'; +CREATE FUNCTION wrap_do_analyze(c INT) RETURNS INT IMMUTABLE LANGUAGE SQL + AS 'SELECT $1 FROM do_analyze()'; +CREATE INDEX ON vactst(wrap_do_analyze(i)); +INSERT INTO vactst VALUES (1), (2); +ANALYZE vactst; +ERROR: ANALYZE cannot be executed from VACUUM or ANALYZE +CONTEXT: SQL function "do_analyze" statement 1 +SQL function "wrap_do_analyze" statement 1 VACUUM FULL pg_am; VACUUM FULL pg_class; VACUUM FULL pg_database; VACUUM FULL vaccluster; VACUUM FULL vactst; +ERROR: ANALYZE cannot be executed from VACUUM or ANALYZE +CONTEXT: SQL function "do_analyze" statement 1 +SQL function "wrap_do_analyze" statement 1 DROP TABLE vaccluster; DROP TABLE vactst; diff --git a/src/test/regress/sql/vacuum.sql b/src/test/regress/sql/vacuum.sql index 30551ad1f2..4b624fe379 100644 --- a/src/test/regress/sql/vacuum.sql +++ b/src/test/regress/sql/vacuum.sql @@ -44,9 +44,16 @@ VACUUM (ANALYZE, FULL) vactst; CREATE TABLE vaccluster (i INT PRIMARY KEY); ALTER TABLE vaccluster CLUSTER ON vaccluster_pkey; -INSERT INTO vaccluster SELECT * FROM vactst; CLUSTER vaccluster; +CREATE FUNCTION do_analyze() RETURNS VOID VOLATILE LANGUAGE SQL + AS 'ANALYZE pg_am'; +CREATE FUNCTION wrap_do_analyze(c INT) RETURNS INT IMMUTABLE LANGUAGE SQL + AS 'SELECT $1 FROM do_analyze()'; +CREATE INDEX ON vactst(wrap_do_analyze(i)); +INSERT INTO vactst VALUES (1), (2); +ANALYZE vactst; + VACUUM FULL pg_am; VACUUM FULL pg_class; VACUUM FULL pg_database; -- 2.40.0