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).
This commit is contained in:
Noah Misch 2015-01-07 22:33:58 -05:00
parent 39f2594ba5
commit e415b469b3
3 changed files with 33 additions and 4 deletions

View File

@ -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;
/*

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@ -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;

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@ -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;