1 files changed, 49 insertions, 18 deletions

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 7fcc3db14cb..5f46aaa9dad 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -269,7 +269,9 @@ struct DropRelationCallbackState
 #define		ATT_COMPOSITE_TYPE		0x0010
 #define		ATT_FOREIGN_TABLE		0x0020
 
-static void truncate_check_rel(Relation rel);
+static void truncate_check_rel(Oid relid, Form_pg_class reltuple);
+static void truncate_check_perms(Oid relid, Form_pg_class reltuple);
+static void truncate_check_activity(Relation rel);
 static List *MergeAttributes(List *schema, List *supers, char relpersistence,
 				List **supOids, List **supconstr, int *supOidCount);
 static bool MergeCheckConstraint(List *constraints, char *name, Node *expr);
@@ -1046,7 +1048,11 @@ ExecuteTruncate(TruncateStmt *stmt)
 			heap_close(rel, lockmode);
 			continue;
 		}
-		truncate_check_rel(rel);
+
+		truncate_check_rel(myrelid, rel->rd_rel);
+		truncate_check_perms(myrelid, rel->rd_rel);
+		truncate_check_activity(rel);
+
 		rels = lappend(rels, rel);
 		relids = lappend_oid(relids, myrelid);
 
@@ -1082,7 +1088,15 @@ ExecuteTruncate(TruncateStmt *stmt)
 					continue;
 				}
 
-				truncate_check_rel(rel);
+				/*
+				 * Inherited TRUNCATE commands perform access
+				 * permission checks on the parent table only.
+				 * So we skip checking the children's permissions
+				 * and don't call truncate_check_perms() here.
+				 */
+				truncate_check_rel(RelationGetRelid(rel), rel->rd_rel);
+				truncate_check_activity(rel);
+
 				rels = lappend(rels, rel);
 				relids = lappend_oid(relids, childrelid);
 			}
@@ -1116,7 +1130,9 @@ ExecuteTruncate(TruncateStmt *stmt)
 				ereport(NOTICE,
 						(errmsg("truncate cascades to table \"%s\"",
 								RelationGetRelationName(rel))));
-				truncate_check_rel(rel);
+				truncate_check_rel(relid, rel->rd_rel);
+				truncate_check_perms(relid, rel->rd_rel);
+				truncate_check_activity(rel);
 				rels = lappend(rels, rel);
 				relids = lappend_oid(relids, relid);
 			}
@@ -1324,30 +1340,45 @@ ExecuteTruncate(TruncateStmt *stmt)
  * Check that a given rel is safe to truncate.  Subroutine for ExecuteTruncate
  */
 static void
-truncate_check_rel(Relation rel)
+truncate_check_rel(Oid relid, Form_pg_class reltuple)
 {
-	AclResult	aclresult;
+	char	   *relname = NameStr(reltuple->relname);
 
 	/* Only allow truncate on regular tables */
-	if (rel->rd_rel->relkind != RELKIND_RELATION)
+	if (reltuple->relkind != RELKIND_RELATION)
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
-				 errmsg("\"%s\" is not a table",
-						RelationGetRelationName(rel))));
+				 errmsg("\"%s\" is not a table", relname)));
 
-	/* Permissions checks */
-	aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
-								  ACL_TRUNCATE);
-	if (aclresult != ACLCHECK_OK)
-		aclcheck_error(aclresult, ACL_KIND_CLASS,
-					   RelationGetRelationName(rel));
-
-	if (!allowSystemTableMods && IsSystemRelation(rel))
+	if (!allowSystemTableMods && IsSystemClass(relid, reltuple))
 		ereport(ERROR,
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 errmsg("permission denied: \"%s\" is a system catalog",
-						RelationGetRelationName(rel))));
+						relname)));
+}
 
+/*
+ * Check that current user has the permission to truncate given relation.
+ */
+static void
+truncate_check_perms(Oid relid, Form_pg_class reltuple)
+{
+	char	   *relname = NameStr(reltuple->relname);
+	AclResult	aclresult;
+
+	/* Permissions checks */
+	aclresult = pg_class_aclcheck(relid, GetUserId(), ACL_TRUNCATE);
+	if (aclresult != ACLCHECK_OK)
+		aclcheck_error(aclresult, ACL_KIND_CLASS, relname);
+}
+
+/*
+ * Set of extra sanity checks to check if a given relation is safe to
+ * truncate.
+ */
+static void
+truncate_check_activity(Relation rel)
+{
 	/*
 	 * Don't allow truncate on temp tables of other backends ... their local
 	 * buffer manager is not going to cope.