From 43d4e965edf119b4f12df3e1488c82f32bfa9fe0 Mon Sep 17 00:00:00 2001 From: Robert Haas Date: Mon, 17 Feb 2014 09:33:31 -0500 Subject: [PATCH] Avoid repeated name lookups during table and index DDL. If the name lookups come to different conclusions due to concurrent activity, we might perform some parts of the DDL on a different table than other parts. At least in the case of CREATE INDEX, this can be used to cause the permissions checks to be performed against a different table than the index creation, allowing for a privilege escalation attack. This changes the calling convention for DefineIndex, CreateTrigger, transformIndexStmt, transformAlterTableStmt, CheckIndexCompatible (in 9.2 and newer), and AlterTable (in 9.1 and older). In addition, CheckRelationOwnership is removed in 9.2 and newer and the calling convention is changed in older branches. A field has also been added to the Constraint node (FkConstraint in 8.4). Third-party code calling these functions or using the Constraint node will require updating. Report by Andres Freund. Patch by Robert Haas and Andres Freund, reviewed by Tom Lane. Security: CVE-2014-0062 --- src/backend/bootstrap/bootparse.y | 15 +++- src/backend/catalog/index.c | 14 +-- src/backend/catalog/pg_constraint.c | 19 ++++ src/backend/commands/alter.c | 4 +- src/backend/commands/indexcmds.c | 23 +++-- src/backend/commands/tablecmds.c | 132 ++++++++++++++++++---------- src/backend/commands/trigger.c | 25 ++++-- src/backend/nodes/copyfuncs.c | 1 + src/backend/nodes/equalfuncs.c | 1 + src/backend/nodes/outfuncs.c | 1 + src/backend/parser/parse_utilcmd.c | 47 +++++----- src/backend/tcop/utility.c | 50 ++++++++--- src/include/catalog/index.h | 1 + src/include/catalog/pg_constraint.h | 1 + src/include/commands/defrem.h | 2 +- src/include/commands/tablecmds.h | 2 +- src/include/commands/trigger.h | 2 +- src/include/nodes/parsenodes.h | 1 + src/include/parser/parse_utilcmd.h | 5 +- src/include/tcop/utility.h | 2 +- 20 files changed, 230 insertions(+), 118 deletions(-) diff --git a/src/backend/bootstrap/bootparse.y b/src/backend/bootstrap/bootparse.y index 9cc68501ff..72ebe7046b 100644 --- a/src/backend/bootstrap/bootparse.y +++ b/src/backend/bootstrap/bootparse.y @@ -27,6 +27,7 @@ #include "bootstrap/bootstrap.h" #include "catalog/catalog.h" #include "catalog/heap.h" +#include "catalog/namespace.h" #include "catalog/pg_am.h" #include "catalog/pg_attribute.h" #include "catalog/pg_authid.h" @@ -277,9 +278,14 @@ Boot_InsertStmt: Boot_DeclareIndexStmt: XDECLARE INDEX boot_ident oidspec ON boot_ident USING boot_ident LPAREN boot_index_params RPAREN { + Oid relationId; + do_start(); - DefineIndex(makeRangeVar(NULL, $6, -1), + relationId = RangeVarGetRelid(makeRangeVar(NULL, $6, -1), + false); + + DefineIndex(relationId, $3, $4, $8, @@ -295,9 +301,14 @@ Boot_DeclareIndexStmt: Boot_DeclareUniqueIndexStmt: XDECLARE UNIQUE INDEX boot_ident oidspec ON boot_ident USING boot_ident LPAREN boot_index_params RPAREN { + Oid relationId; + do_start(); - DefineIndex(makeRangeVar(NULL, $7, -1), + relationId = RangeVarGetRelid(makeRangeVar(NULL, $7, -1), + false); + + DefineIndex(relationId, $4, $5, $9, diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c index 40712988cd..8903a7601a 100644 --- a/src/backend/catalog/index.c +++ b/src/backend/catalog/index.c @@ -109,7 +109,6 @@ static void validate_index_heapscan(Relation heapRelation, IndexInfo *indexInfo, Snapshot snapshot, v_i_state *state); -static Oid IndexGetRelation(Oid indexId); static void SetReindexProcessing(Oid heapOid, Oid indexOid); static void ResetReindexProcessing(void); static void SetReindexPending(List *indexes); @@ -806,17 +805,12 @@ index_create(Oid heapRelationId, */ if (deferrable) { - RangeVar *heapRel; CreateTrigStmt *trigger; - heapRel = makeRangeVar(get_namespace_name(namespaceId), - pstrdup(RelationGetRelationName(heapRelation)), - -1); - trigger = makeNode(CreateTrigStmt); trigger->trigname = (isprimary ? "PK_ConstraintTrigger" : "Unique_ConstraintTrigger"); - trigger->relation = heapRel; + trigger->relation = NULL; trigger->funcname = SystemFuncName("unique_key_recheck"); trigger->args = NIL; trigger->before = false; @@ -829,8 +823,8 @@ index_create(Oid heapRelationId, trigger->initdeferred = initdeferred; trigger->constrrel = NULL; - (void) CreateTrigger(trigger, NULL, conOid, indexRelationId, - true); + (void) CreateTrigger(trigger, NULL, heapRelationId, InvalidOid, + conOid, indexRelationId, true); } } else @@ -2483,7 +2477,7 @@ index_set_state_flags(Oid indexId, IndexStateFlagsAction action) * IndexGetRelation: given an index's relation OID, get the OID of the * relation it is an index on. Uses the system cache. */ -static Oid +Oid IndexGetRelation(Oid indexId) { HeapTuple tuple; diff --git a/src/backend/catalog/pg_constraint.c b/src/backend/catalog/pg_constraint.c index 84dab8eb21..2da823bd95 100644 --- a/src/backend/catalog/pg_constraint.c +++ b/src/backend/catalog/pg_constraint.c @@ -726,6 +726,25 @@ AlterConstraintNamespaces(Oid ownerId, Oid oldNspId, heap_close(conRel, RowExclusiveLock); } +/* + * get_constraint_relation_oids + * Find the IDs of the relations to which a constraint refers. + */ +void +get_constraint_relation_oids(Oid constraint_oid, Oid *conrelid, Oid *confrelid) +{ + HeapTuple tup; + Form_pg_constraint con; + + tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraint_oid)); + if (!HeapTupleIsValid(tup)) /* should not happen */ + elog(ERROR, "cache lookup failed for constraint %u", constraint_oid); + con = (Form_pg_constraint) GETSTRUCT(tup); + *conrelid = con->conrelid; + *confrelid = con->confrelid; + ReleaseSysCache(tup); +} + /* * GetConstraintByName * Find a constraint on the specified relation with the specified name. diff --git a/src/backend/commands/alter.c b/src/backend/commands/alter.c index cecdfa5c6d..d031938db8 100644 --- a/src/backend/commands/alter.c +++ b/src/backend/commands/alter.c @@ -93,9 +93,8 @@ ExecRenameStmt(RenameStmt *stmt) { Oid relid; - CheckRelationOwnership(stmt->relation, true); - relid = RangeVarGetRelid(stmt->relation, false); + CheckRelationOwnership(relid, true); switch (stmt->renameType) { @@ -188,7 +187,6 @@ ExecAlterObjectSchemaStmt(AlterObjectSchemaStmt *stmt) case OBJECT_SEQUENCE: case OBJECT_TABLE: case OBJECT_VIEW: - CheckRelationOwnership(stmt->relation, true); AlterTableNamespace(stmt->relation, stmt->newschema, stmt->objectType); break; diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index 09c8d62f5d..565aaf2272 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -76,7 +76,8 @@ static bool relationHasPrimaryKey(Relation rel); * DefineIndex * Creates a new index. * - * 'heapRelation': the relation the index will apply to. + * 'relationId': the OID of the heap relation on which the index is to be + * created * 'indexRelationName': the name for the new index, or NULL to indicate * that a nonconflicting default name should be picked. * 'indexRelationId': normally InvalidOid, but during bootstrap can be @@ -105,7 +106,7 @@ static bool relationHasPrimaryKey(Relation rel); * 'concurrent': avoid blocking writers to the table while building. */ void -DefineIndex(RangeVar *heapRelation, +DefineIndex(Oid relationId, char *indexRelationName, Oid indexRelationId, char *accessMethodName, @@ -127,7 +128,6 @@ DefineIndex(RangeVar *heapRelation, { Oid *classObjectId; Oid accessMethodId; - Oid relationId; Oid namespaceId; Oid tablespaceId; List *indexColNames; @@ -147,6 +147,7 @@ DefineIndex(RangeVar *heapRelation, int n_old_snapshots; LockRelId heaprelid; LOCKTAG heaplocktag; + LOCKMODE lockmode; Snapshot snapshot; int i; @@ -165,14 +166,18 @@ DefineIndex(RangeVar *heapRelation, INDEX_MAX_KEYS))); /* - * Open heap relation, acquire a suitable lock on it, remember its OID - * * Only SELECT ... FOR UPDATE/SHARE are allowed while doing a standard * index build; but for concurrent builds we allow INSERT/UPDATE/DELETE * (but not VACUUM). + * + * NB: Caller is responsible for making sure that relationId refers + * to the relation on which the index should be built; except in bootstrap + * mode, this will typically require the caller to have already locked + * the relation. To avoid lock upgrade hazards, that lock should be at + * least as strong as the one we take here. */ - rel = heap_openrv(heapRelation, - (concurrent ? ShareUpdateExclusiveLock : ShareLock)); + lockmode = concurrent ? ShareUpdateExclusiveLock : ShareLock; + rel = heap_open(relationId, lockmode); relationId = RelationGetRelid(rel); namespaceId = RelationGetNamespace(rel); @@ -183,7 +188,7 @@ DefineIndex(RangeVar *heapRelation, ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("\"%s\" is not a table", - heapRelation->relname))); + RelationGetRelationName(rel)))); /* * Don't try to CREATE INDEX on temp tables of other backends. @@ -567,7 +572,7 @@ DefineIndex(RangeVar *heapRelation, */ /* Open and lock the parent heap relation */ - rel = heap_openrv(heapRelation, ShareUpdateExclusiveLock); + rel = heap_open(relationId, ShareUpdateExclusiveLock); /* And the target index relation */ indexRelation = index_open(indexRelationId, RowExclusiveLock); diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 03a678626f..da058df74c 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -66,6 +66,7 @@ #include "storage/bufmgr.h" #include "storage/lmgr.h" #include "storage/smgr.h" +#include "tcop/utility.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/fmgroids.h" @@ -251,7 +252,8 @@ static void checkFkeyPermissions(Relation rel, int16 *attnums, int natts); static void validateForeignKeyConstraint(Constraint *fkconstraint, Relation rel, Relation pkrel, Oid pkindOid, Oid constraintOid); -static void createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, +static void createForeignKeyTriggers(Relation rel, Oid refRelOid, + Constraint *fkconstraint, Oid constraintOid, Oid indexOid); static void ATController(Relation rel, List *cmds, bool recurse); static void ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd, @@ -315,7 +317,8 @@ static void ATPrepAlterColumnType(List **wqueue, static void ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel, const char *colName, TypeName *typeName); static void ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab); -static void ATPostAlterTypeParse(char *cmd, List **wqueue); +static void ATPostAlterTypeParse(Oid oldRelId, Oid refRelId, char *cmd, + List **wqueue); static void change_owner_fix_column_acls(Oid relationOid, Oid oldOwnerId, Oid newOwnerId); static void change_owner_recurse_to_sequences(Oid relationOid, @@ -2248,9 +2251,12 @@ CheckTableNotInUse(Relation rel, const char *stmt) * the whole operation; we don't have to do anything special to clean up. */ void -AlterTable(AlterTableStmt *stmt) +AlterTable(Oid relid, AlterTableStmt *stmt) { - Relation rel = relation_openrv(stmt->relation, AccessExclusiveLock); + Relation rel; + + /* Caller is required to provide an adequate lock. */ + rel = relation_open(relid, NoLock); CheckTableNotInUse(rel, "ALTER TABLE"); @@ -4496,7 +4502,7 @@ ATExecAddIndex(AlteredTableInfo *tab, Relation rel, /* The IndexStmt has already been through transformIndexStmt */ - DefineIndex(stmt->relation, /* relation */ + DefineIndex(RelationGetRelid(rel), /* relation */ stmt->idxname, /* index name */ InvalidOid, /* no predefined OID */ stmt->accessMethod, /* am name */ @@ -4735,7 +4741,10 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel, * table; trying to start with a lesser lock will just create a risk of * deadlock.) */ - pkrel = heap_openrv(fkconstraint->pktable, AccessExclusiveLock); + if (OidIsValid(fkconstraint->old_pktable_oid)) + pkrel = heap_open(fkconstraint->old_pktable_oid, AccessExclusiveLock); + else + pkrel = heap_openrv(fkconstraint->pktable, AccessExclusiveLock); /* * Validity checks (permission checks wait till we have the column @@ -4970,7 +4979,8 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel, /* * Create the triggers that will enforce the constraint. */ - createForeignKeyTriggers(rel, fkconstraint, constrOid, indexOid); + createForeignKeyTriggers(rel, RelationGetRelid(pkrel), fkconstraint, + constrOid, indexOid); /* * Tell Phase 3 to check that the constraint is satisfied by existing rows @@ -5376,14 +5386,14 @@ validateForeignKeyConstraint(Constraint *fkconstraint, } static void -CreateFKCheckTrigger(RangeVar *myRel, Constraint *fkconstraint, +CreateFKCheckTrigger(Oid myRelOid, Oid refRelOid, Constraint *fkconstraint, Oid constraintOid, Oid indexOid, bool on_insert) { CreateTrigStmt *fk_trigger; fk_trigger = makeNode(CreateTrigStmt); fk_trigger->trigname = "RI_ConstraintTrigger"; - fk_trigger->relation = myRel; + fk_trigger->relation = NULL; fk_trigger->before = false; fk_trigger->row = true; @@ -5404,10 +5414,11 @@ CreateFKCheckTrigger(RangeVar *myRel, Constraint *fkconstraint, fk_trigger->isconstraint = true; fk_trigger->deferrable = fkconstraint->deferrable; fk_trigger->initdeferred = fkconstraint->initdeferred; - fk_trigger->constrrel = fkconstraint->pktable; + fk_trigger->constrrel = NULL; fk_trigger->args = NIL; - (void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, true); + (void) CreateTrigger(fk_trigger, NULL, myRelOid, refRelOid, constraintOid, + indexOid, true); /* Make changes-so-far visible */ CommandCounterIncrement(); @@ -5417,18 +5428,13 @@ CreateFKCheckTrigger(RangeVar *myRel, Constraint *fkconstraint, * Create the triggers that implement an FK constraint. */ static void -createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, +createForeignKeyTriggers(Relation rel, Oid refRelOid, Constraint *fkconstraint, Oid constraintOid, Oid indexOid) { - RangeVar *myRel; + Oid myRelOid; CreateTrigStmt *fk_trigger; - /* - * Reconstruct a RangeVar for my relation (not passed in, unfortunately). - */ - myRel = makeRangeVar(get_namespace_name(RelationGetNamespace(rel)), - pstrdup(RelationGetRelationName(rel)), - -1); + myRelOid = RelationGetRelid(rel); /* Make changes-so-far visible */ CommandCounterIncrement(); @@ -5439,14 +5445,14 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, */ fk_trigger = makeNode(CreateTrigStmt); fk_trigger->trigname = "RI_ConstraintTrigger"; - fk_trigger->relation = fkconstraint->pktable; + fk_trigger->relation = NULL; fk_trigger->before = false; fk_trigger->row = true; fk_trigger->events = TRIGGER_TYPE_DELETE; fk_trigger->columns = NIL; fk_trigger->whenClause = NULL; fk_trigger->isconstraint = true; - fk_trigger->constrrel = myRel; + fk_trigger->constrrel = NULL; switch (fkconstraint->fk_del_action) { case FKCONSTR_ACTION_NOACTION: @@ -5481,7 +5487,8 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, } fk_trigger->args = NIL; - (void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, true); + (void) CreateTrigger(fk_trigger, NULL, refRelOid, myRelOid, constraintOid, + indexOid, true); /* Make changes-so-far visible */ CommandCounterIncrement(); @@ -5492,14 +5499,14 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, */ fk_trigger = makeNode(CreateTrigStmt); fk_trigger->trigname = "RI_ConstraintTrigger"; - fk_trigger->relation = fkconstraint->pktable; + fk_trigger->relation = NULL; fk_trigger->before = false; fk_trigger->row = true; fk_trigger->events = TRIGGER_TYPE_UPDATE; fk_trigger->columns = NIL; fk_trigger->whenClause = NULL; fk_trigger->isconstraint = true; - fk_trigger->constrrel = myRel; + fk_trigger->constrrel = NULL; switch (fkconstraint->fk_upd_action) { case FKCONSTR_ACTION_NOACTION: @@ -5534,7 +5541,8 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, } fk_trigger->args = NIL; - (void) CreateTrigger(fk_trigger, NULL, constraintOid, indexOid, true); + (void) CreateTrigger(fk_trigger, NULL, refRelOid, myRelOid, constraintOid, + indexOid, true); /* Make changes-so-far visible */ CommandCounterIncrement(); @@ -5554,8 +5562,10 @@ createForeignKeyTriggers(Relation rel, Constraint *fkconstraint, * and the use of self-referential FKs is rare enough, that we live with * it for now. There will be a real fix in PG 9.2. */ - CreateFKCheckTrigger(myRel, fkconstraint, constraintOid, indexOid, true); - CreateFKCheckTrigger(myRel, fkconstraint, constraintOid, indexOid, false); + CreateFKCheckTrigger(myRelOid, refRelOid, fkconstraint, constraintOid, + indexOid, true); + CreateFKCheckTrigger(myRelOid, refRelOid, fkconstraint, constraintOid, + indexOid, false); } /* @@ -6274,7 +6284,8 @@ static void ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab) { ObjectAddress obj; - ListCell *l; + ListCell *def_item; + ListCell *oid_item; /* * Re-parse the index and constraint definitions, and attach them to the @@ -6283,11 +6294,36 @@ ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab) * lock on the table the constraint is attached to, and we need to get * that before dropping. It's safe because the parser won't actually look * at the catalogs to detect the existing entry. + * + * We can't rely on the output of deparsing to tell us which relation + * to operate on, because concurrent activity might have made the name + * resolve differently. Instead, we've got to use the OID of the + * constraint or index we're processing to figure out which relation + * to operate on. */ - foreach(l, tab->changedIndexDefs) - ATPostAlterTypeParse((char *) lfirst(l), wqueue); - foreach(l, tab->changedConstraintDefs) - ATPostAlterTypeParse((char *) lfirst(l), wqueue); + forboth(oid_item, tab->changedConstraintOids, + def_item, tab->changedConstraintDefs) + { + Oid oldId = lfirst_oid(oid_item); + Oid relid; + Oid confrelid; + + get_constraint_relation_oids(oldId, &relid, &confrelid); + ATPostAlterTypeParse(relid, confrelid, + (char *) lfirst(def_item), + wqueue); + } + forboth(oid_item, tab->changedIndexOids, + def_item, tab->changedIndexDefs) + { + Oid oldId = lfirst_oid(oid_item); + Oid relid; + + relid = IndexGetRelation(oldId); + ATPostAlterTypeParse(relid, InvalidOid, + (char *) lfirst(def_item), + wqueue); + } /* * Now we can drop the existing constraints and indexes --- constraints @@ -6297,18 +6333,18 @@ ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab) * should be okay to use DROP_RESTRICT here, since nothing else should be * depending on these objects. */ - foreach(l, tab->changedConstraintOids) + foreach(oid_item, tab->changedConstraintOids) { obj.classId = ConstraintRelationId; - obj.objectId = lfirst_oid(l); + obj.objectId = lfirst_oid(oid_item); obj.objectSubId = 0; performDeletion(&obj, DROP_RESTRICT); } - foreach(l, tab->changedIndexOids) + foreach(oid_item, tab->changedIndexOids) { obj.classId = RelationRelationId; - obj.objectId = lfirst_oid(l); + obj.objectId = lfirst_oid(oid_item); obj.objectSubId = 0; performDeletion(&obj, DROP_RESTRICT); } @@ -6320,11 +6356,12 @@ ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab) } static void -ATPostAlterTypeParse(char *cmd, List **wqueue) +ATPostAlterTypeParse(Oid oldRelId, Oid refRelId, char *cmd, List **wqueue) { List *raw_parsetree_list; List *querytree_list; ListCell *list_item; + Relation rel; /* * We expect that we will get only ALTER TABLE and CREATE INDEX @@ -6340,16 +6377,21 @@ ATPostAlterTypeParse(char *cmd, List **wqueue) if (IsA(stmt, IndexStmt)) querytree_list = lappend(querytree_list, - transformIndexStmt((IndexStmt *) stmt, + transformIndexStmt(oldRelId, + (IndexStmt *) stmt, cmd)); else if (IsA(stmt, AlterTableStmt)) querytree_list = list_concat(querytree_list, - transformAlterTableStmt((AlterTableStmt *) stmt, + transformAlterTableStmt(oldRelId, + (AlterTableStmt *) stmt, cmd)); else querytree_list = lappend(querytree_list, stmt); } + /* Caller should already have acquired whatever lock we need. */ + rel = relation_open(oldRelId, NoLock); + /* * Attach each generated command to the proper place in the work queue. * Note this could result in creation of entirely new work-queue entries. @@ -6361,7 +6403,6 @@ ATPostAlterTypeParse(char *cmd, List **wqueue) foreach(list_item, querytree_list) { Node *stm = (Node *) lfirst(list_item); - Relation rel; AlteredTableInfo *tab; switch (nodeTag(stm)) @@ -6371,14 +6412,12 @@ ATPostAlterTypeParse(char *cmd, List **wqueue) IndexStmt *stmt = (IndexStmt *) stm; AlterTableCmd *newcmd; - rel = relation_openrv(stmt->relation, AccessExclusiveLock); tab = ATGetQueueEntry(wqueue, rel); newcmd = makeNode(AlterTableCmd); newcmd->subtype = AT_ReAddIndex; newcmd->def = (Node *) stmt; tab->subcmds[AT_PASS_OLD_INDEX] = lappend(tab->subcmds[AT_PASS_OLD_INDEX], newcmd); - relation_close(rel, NoLock); break; } case T_AlterTableStmt: @@ -6386,7 +6425,6 @@ ATPostAlterTypeParse(char *cmd, List **wqueue) AlterTableStmt *stmt = (AlterTableStmt *) stm; ListCell *lcmd; - rel = relation_openrv(stmt->relation, AccessExclusiveLock); tab = ATGetQueueEntry(wqueue, rel); foreach(lcmd, stmt->cmds) { @@ -6409,7 +6447,6 @@ ATPostAlterTypeParse(char *cmd, List **wqueue) (int) cmd->subtype); } } - relation_close(rel, NoLock); break; } default: @@ -6417,8 +6454,9 @@ ATPostAlterTypeParse(char *cmd, List **wqueue) (int) nodeTag(stm)); } } -} + relation_close(rel, NoLock); +} /* * ALTER TABLE OWNER @@ -7815,7 +7853,8 @@ ATExecDropInherit(Relation rel, RangeVar *parent) /* * Execute ALTER TABLE SET SCHEMA * - * Note: caller must have checked ownership of the relation already + * WARNING WARNING WARNING: In previous *minor* releases the caller was + * responsible for checking ownership of the relation, but now we do it here. */ void AlterTableNamespace(RangeVar *relation, const char *newschema, @@ -7830,6 +7869,7 @@ AlterTableNamespace(RangeVar *relation, const char *newschema, rel = relation_openrv(relation, AccessExclusiveLock); relid = RelationGetRelid(rel); + CheckRelationOwnership(relid, true); oldNspOid = RelationGetNamespace(rel); /* Check relation type against type specified in the ALTER command */ diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index f62a03f4fa..6dcab778f9 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -90,6 +90,13 @@ static void AfterTriggerSaveEvent(EState *estate, ResultRelInfo *relinfo, * queryString is the source text of the CREATE TRIGGER command. * This must be supplied if a whenClause is specified, else it can be NULL. * + * relOid, if nonzero, is the relation on which the trigger should be + * created. If zero, the name provided in the statement will be looked up. + * + * refRelOid, if nonzero, is the relation to which the constraint trigger + * refers. If zero, the constraint relation name provided in the statement + * will be looked up as needed. + * * constraintOid, if nonzero, says that this trigger is being created * internally to implement that constraint. A suitable pg_depend entry will * be made to link the trigger to that constraint. constraintOid is zero when @@ -112,7 +119,7 @@ static void AfterTriggerSaveEvent(EState *estate, ResultRelInfo *relinfo, */ Oid CreateTrigger(CreateTrigStmt *stmt, const char *queryString, - Oid constraintOid, Oid indexOid, + Oid relOid, Oid refRelOid, Oid constraintOid, Oid indexOid, bool isInternal) { int16 tgtype; @@ -141,7 +148,10 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString, ObjectAddress myself, referenced; - rel = heap_openrv(stmt->relation, AccessExclusiveLock); + if (OidIsValid(relOid)) + rel = heap_open(relOid, AccessExclusiveLock); + else + rel = heap_openrv(stmt->relation, AccessExclusiveLock); if (rel->rd_rel->relkind != RELKIND_RELATION) ereport(ERROR, @@ -155,8 +165,13 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString, errmsg("permission denied: \"%s\" is a system catalog", RelationGetRelationName(rel)))); - if (stmt->isconstraint && stmt->constrrel != NULL) - constrrelid = RangeVarGetRelid(stmt->constrrel, false); + if (stmt->isconstraint) + { + if (OidIsValid(refRelOid)) + constrrelid = refRelOid; + else if (stmt->constrrel != NULL) + constrrelid = RangeVarGetRelid(stmt->constrrel, false); + } /* permission checks */ if (!isInternal) @@ -443,7 +458,7 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString, ereport(ERROR, (errcode(ERRCODE_DUPLICATE_OBJECT), errmsg("trigger \"%s\" for relation \"%s\" already exists", - trigname, stmt->relation->relname))); + trigname, RelationGetRelationName(rel)))); } systable_endscan(tgscan); } diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c index f0d3246fa2..0dd236d743 100644 --- a/src/backend/nodes/copyfuncs.c +++ b/src/backend/nodes/copyfuncs.c @@ -2181,6 +2181,7 @@ _copyConstraint(Constraint *from) COPY_SCALAR_FIELD(fk_upd_action); COPY_SCALAR_FIELD(fk_del_action); COPY_SCALAR_FIELD(skip_validation); + COPY_SCALAR_FIELD(old_pktable_oid); return newnode; } diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c index acce5747e2..3cbcb319b4 100644 --- a/src/backend/nodes/equalfuncs.c +++ b/src/backend/nodes/equalfuncs.c @@ -2138,6 +2138,7 @@ _equalConstraint(Constraint *a, Constraint *b) COMPARE_SCALAR_FIELD(fk_upd_action); COMPARE_SCALAR_FIELD(fk_del_action); COMPARE_SCALAR_FIELD(skip_validation); + COMPARE_SCALAR_FIELD(old_pktable_oid); return true; } diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c index d3007edca1..af7dc5db94 100644 --- a/src/backend/nodes/outfuncs.c +++ b/src/backend/nodes/outfuncs.c @@ -2428,6 +2428,7 @@ _outConstraint(StringInfo str, Constraint *node) WRITE_CHAR_FIELD(fk_upd_action); WRITE_CHAR_FIELD(fk_del_action); WRITE_BOOL_FIELD(skip_validation); + WRITE_OID_FIELD(old_pktable_oid); break; case CONSTR_ATTR_DEFERRABLE: diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index afd38c3ef9..06b64f03fe 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -1602,14 +1602,18 @@ transformFKConstraints(ParseState *pstate, CreateStmtContext *cxt, * a predicate expression. There are several code paths that create indexes * without bothering to call this, because they know they don't have any * such expressions to deal with. + * + * To avoid race conditions, it's important that this function rely only on + * the passed-in relid (and not on stmt->relation) to determine the target + * relation. */ IndexStmt * -transformIndexStmt(IndexStmt *stmt, const char *queryString) +transformIndexStmt(Oid relid, IndexStmt *stmt, const char *queryString) { - Relation rel; ParseState *pstate; RangeTblEntry *rte; ListCell *l; + Relation rel; /* * We must not scribble on the passed-in IndexStmt, so copy it. (This is @@ -1617,25 +1621,17 @@ transformIndexStmt(IndexStmt *stmt, const char *queryString) */ stmt = (IndexStmt *) copyObject(stmt); - /* - * Open the parent table with appropriate locking. We must do this - * because addRangeTableEntry() would acquire only AccessShareLock, - * leaving DefineIndex() needing to do a lock upgrade with consequent risk - * of deadlock. Make sure this stays in sync with the type of lock - * DefineIndex() wants. - */ - rel = heap_openrv(stmt->relation, - (stmt->concurrent ? ShareUpdateExclusiveLock : ShareLock)); - /* Set up pstate */ pstate = make_parsestate(NULL); pstate->p_sourcetext = queryString; /* * Put the parent table into the rtable so that the expressions can refer - * to its fields without qualification. + * to its fields without qualification. Caller is responsible for locking + * relation, but we still need to open it. */ - rte = addRangeTableEntry(pstate, stmt->relation, NULL, false, true); + rel = relation_open(relid, NoLock); + rte = addRangeTableEntryForRelation(pstate, rel, NULL, false, true); /* no to join list, yes to namespaces */ addRTEtoQuery(pstate, rte, false, true, true); @@ -1682,7 +1678,7 @@ transformIndexStmt(IndexStmt *stmt, const char *queryString) free_parsestate(pstate); - /* Close relation, but keep the lock */ + /* Close relation */ heap_close(rel, NoLock); return stmt; @@ -1973,9 +1969,14 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString, * Returns a List of utility commands to be done in sequence. One of these * will be the transformed AlterTableStmt, but there may be additional actions * to be done before and after the actual AlterTable() call. + * + * To avoid race conditions, it's important that this function rely only on + * the passed-in relid (and not on stmt->relation) to determine the target + * relation. */ List * -transformAlterTableStmt(AlterTableStmt *stmt, const char *queryString) +transformAlterTableStmt(Oid relid, AlterTableStmt *stmt, + const char *queryString) { Relation rel; ParseState *pstate; @@ -1994,14 +1995,8 @@ transformAlterTableStmt(AlterTableStmt *stmt, const char *queryString) */ stmt = (AlterTableStmt *) copyObject(stmt); - /* - * Acquire exclusive lock on the target relation, which will be held until - * end of transaction. This ensures any decisions we make here based on - * the state of the relation will still be good at execution. We must get - * exclusive lock now because execution will; taking a lower grade lock - * now and trying to upgrade later risks deadlock. - */ - rel = relation_openrv(stmt->relation, AccessExclusiveLock); + /* Caller is responsible for locking the relation */ + rel = relation_open(relid, NoLock); /* Set up pstate */ pstate = make_parsestate(NULL); @@ -2116,7 +2111,7 @@ transformAlterTableStmt(AlterTableStmt *stmt, const char *queryString) Assert(IsA(idxstmt, IndexStmt)); newcmd = makeNode(AlterTableCmd); newcmd->subtype = AT_AddIndex; - newcmd->def = (Node *) transformIndexStmt((IndexStmt *) idxstmt, + newcmd->def = (Node *) transformIndexStmt(relid, (IndexStmt *) idxstmt, queryString); newcmds = lappend(newcmds, newcmd); } @@ -2138,7 +2133,7 @@ transformAlterTableStmt(AlterTableStmt *stmt, const char *queryString) newcmds = lappend(newcmds, newcmd); } - /* Close rel but keep lock */ + /* Close rel */ relation_close(rel, NoLock); /* diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c index c2d15a1728..82499987ee 100644 --- a/src/backend/tcop/utility.c +++ b/src/backend/tcop/utility.c @@ -51,11 +51,13 @@ #include "rewrite/rewriteDefine.h" #include "rewrite/rewriteRemove.h" #include "storage/fd.h" +#include "storage/lmgr.h" #include "tcop/pquery.h" #include "tcop/utility.h" #include "utils/acl.h" #include "utils/guc.h" #include "utils/syscache.h" +#include "utils/lsyscache.h" /* Hook for plugins to get control in ProcessUtility() */ @@ -69,19 +71,17 @@ ProcessUtility_hook_type ProcessUtility_hook = NULL; * except when allowSystemTableMods is true. */ void -CheckRelationOwnership(RangeVar *rel, bool noCatalogs) +CheckRelationOwnership(Oid relOid, bool noCatalogs) { - Oid relOid; HeapTuple tuple; - relOid = RangeVarGetRelid(rel, false); tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relOid)); if (!HeapTupleIsValid(tuple)) /* should not happen */ elog(ERROR, "cache lookup failed for relation %u", relOid); if (!pg_class_ownercheck(relOid, GetUserId())) aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS, - rel->relname); + get_rel_name(relOid)); if (noCatalogs) { @@ -90,7 +90,7 @@ CheckRelationOwnership(RangeVar *rel, bool noCatalogs) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied: \"%s\" is a system catalog", - rel->relname))); + get_rel_name(relOid)))); } ReleaseSysCache(tuple); @@ -701,9 +701,21 @@ standard_ProcessUtility(Node *parsetree, { List *stmts; ListCell *l; + AlterTableStmt *atstmt = (AlterTableStmt *) parsetree; + Oid relid; + + /* + * Look up the relation OID just once, right here at the + * beginning, so that we don't end up repeating the name + * lookup later and latching onto a different relation + * partway through. + */ + relid = RangeVarGetRelid(atstmt->relation, false); + LockRelationOid(relid, AccessExclusiveLock); /* Run parse analysis ... */ - stmts = transformAlterTableStmt((AlterTableStmt *) parsetree, + stmts = transformAlterTableStmt(relid, + atstmt, queryString); /* ... and do it */ @@ -714,7 +726,7 @@ standard_ProcessUtility(Node *parsetree, if (IsA(stmt, AlterTableStmt)) { /* Do the table alteration proper */ - AlterTable((AlterTableStmt *) stmt); + AlterTable(relid, (AlterTableStmt *) stmt); } else { @@ -862,18 +874,33 @@ standard_ProcessUtility(Node *parsetree, case T_IndexStmt: /* CREATE INDEX */ { IndexStmt *stmt = (IndexStmt *) parsetree; + Oid relid; + LOCKMODE lockmode; if (stmt->concurrent) PreventTransactionChain(isTopLevel, "CREATE INDEX CONCURRENTLY"); - CheckRelationOwnership(stmt->relation, true); + /* + * Look up the relation OID just once, right here at the + * beginning, so that we don't end up repeating the name + * lookup later and latching onto a different relation + * partway through. To avoid lock upgrade hazards, it's + * important that we take the strongest lock that will + * eventually be needed here, so the lockmode calculation + * needs to match what DefineIndex() does. + */ + lockmode = stmt->concurrent ? ShareUpdateExclusiveLock + : ShareLock; + relid = RangeVarGetRelid(stmt->relation, false); + LockRelationOid(relid, lockmode); + CheckRelationOwnership(relid, true); /* Run parse analysis ... */ - stmt = transformIndexStmt(stmt, queryString); + stmt = transformIndexStmt(relid, stmt, queryString); /* ... and do it */ - DefineIndex(stmt->relation, /* relation */ + DefineIndex(relid, /* relation */ stmt->idxname, /* index name */ InvalidOid, /* no predefined OID */ stmt->accessMethod, /* am name */ @@ -1040,7 +1067,8 @@ standard_ProcessUtility(Node *parsetree, case T_CreateTrigStmt: (void) CreateTrigger((CreateTrigStmt *) parsetree, queryString, - InvalidOid, InvalidOid, false); + InvalidOid, InvalidOid, InvalidOid, + InvalidOid, false); break; case T_DropPropertyStmt: diff --git a/src/include/catalog/index.h b/src/include/catalog/index.h index a2381b1e5d..f7f11c0103 100644 --- a/src/include/catalog/index.h +++ b/src/include/catalog/index.h @@ -88,5 +88,6 @@ extern bool reindex_relation(Oid relid, bool toast_too, int flags); extern bool ReindexIsProcessingHeap(Oid heapOid); extern bool ReindexIsProcessingIndex(Oid indexOid); +extern Oid IndexGetRelation(Oid indexId); #endif /* INDEX_H */ diff --git a/src/include/catalog/pg_constraint.h b/src/include/catalog/pg_constraint.h index b028fdf85b..053fdc9970 100644 --- a/src/include/catalog/pg_constraint.h +++ b/src/include/catalog/pg_constraint.h @@ -238,5 +238,6 @@ extern char *ChooseConstraintName(const char *name1, const char *name2, extern void AlterConstraintNamespaces(Oid ownerId, Oid oldNspId, Oid newNspId, bool isType); extern Oid GetConstraintByName(Oid relid, const char *conname); +extern void get_constraint_relation_oids(Oid constraint_oid, Oid *conrelid, Oid *confrelid); #endif /* PG_CONSTRAINT_H */ diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h index 51cc976563..deebecc8dd 100644 --- a/src/include/commands/defrem.h +++ b/src/include/commands/defrem.h @@ -18,7 +18,7 @@ /* commands/indexcmds.c */ -extern void DefineIndex(RangeVar *heapRelation, +extern void DefineIndex(Oid relationId, char *indexRelationName, Oid indexRelationId, char *accessMethodName, diff --git a/src/include/commands/tablecmds.h b/src/include/commands/tablecmds.h index 81d0a2927b..2618cbc6eb 100644 --- a/src/include/commands/tablecmds.h +++ b/src/include/commands/tablecmds.h @@ -22,7 +22,7 @@ extern Oid DefineRelation(CreateStmt *stmt, char relkind, Oid ownerId); extern void RemoveRelations(DropStmt *drop); -extern void AlterTable(AlterTableStmt *stmt); +extern void AlterTable(Oid relid, AlterTableStmt *stmt); extern void ATExecChangeOwner(Oid relationOid, Oid newOwnerId, bool recursing); diff --git a/src/include/commands/trigger.h b/src/include/commands/trigger.h index 07ad698e7f..927daed942 100644 --- a/src/include/commands/trigger.h +++ b/src/include/commands/trigger.h @@ -105,7 +105,7 @@ extern PGDLLIMPORT int SessionReplicationRole; #define TRIGGER_DISABLED 'D' extern Oid CreateTrigger(CreateTrigStmt *stmt, const char *queryString, - Oid constraintOid, Oid indexOid, + Oid relOid, Oid refRelOid, Oid constraintOid, Oid indexOid, bool isInternal); extern void DropTrigger(Oid relid, const char *trigname, diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index 5508767ec7..257389c7d0 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -1479,6 +1479,7 @@ typedef struct Constraint char fk_upd_action; /* ON UPDATE action */ char fk_del_action; /* ON DELETE action */ bool skip_validation; /* skip validation of existing rows? */ + Oid old_pktable_oid; /* pg_constraint.confrelid of my former self */ } Constraint; /* ---------------------- diff --git a/src/include/parser/parse_utilcmd.h b/src/include/parser/parse_utilcmd.h index 25fc8ebd63..3148629f74 100644 --- a/src/include/parser/parse_utilcmd.h +++ b/src/include/parser/parse_utilcmd.h @@ -18,9 +18,10 @@ extern List *transformCreateStmt(CreateStmt *stmt, const char *queryString); -extern List *transformAlterTableStmt(AlterTableStmt *stmt, +extern List *transformAlterTableStmt(Oid relid, AlterTableStmt *stmt, const char *queryString); -extern IndexStmt *transformIndexStmt(IndexStmt *stmt, const char *queryString); +extern IndexStmt *transformIndexStmt(Oid relid, IndexStmt *stmt, + const char *queryString); extern void transformRuleStmt(RuleStmt *stmt, const char *queryString, List **actions, Node **whereClause); extern List *transformCreateSchemaStmt(CreateSchemaStmt *stmt); diff --git a/src/include/tcop/utility.h b/src/include/tcop/utility.h index 4970410b6d..2ec0576cce 100644 --- a/src/include/tcop/utility.h +++ b/src/include/tcop/utility.h @@ -40,6 +40,6 @@ extern LogStmtLevel GetCommandLogLevel(Node *parsetree); extern bool CommandIsReadOnly(Node *parsetree); -extern void CheckRelationOwnership(RangeVar *rel, bool noCatalogs); +extern void CheckRelationOwnership(Oid relOid, bool noCatalogs); #endif /* UTILITY_H */ -- 2.50.1