s4-dsdb: Add mem_ctx argument to samdb_ntds_settings_dn

As this value is calculated new each time, we need to give it a context to live on.

If the value is the forced value during provision, a reference is taken.

This was responsible for the memory leak in the replication process.  In the
example I was given, this DN appeared in memory 13596 times!

Andrew Bartlett

Autobuild-User(master): Andrew Bartlett <abartlet@samba.org>
Autobuild-Date(master): Tue Aug 14 10:05:14 CEST 2012 on sn-devel-104

4 files changed, 9 insertions, 8 deletions

diff --git a/source4/dsdb/samdb/ldb_modules/objectclass.c b/source4/dsdb/samdb/ldb_modules/objectclass.c
index d431367b5a..7d34b4e8c3 100644
--- a/source4/dsdb/samdb/ldb_modules/objectclass.c
+++ b/source4/dsdb/samdb/ldb_modules/objectclass.c
@@ -1298,7 +1298,7 @@ static int objectclass_do_delete(struct oc_context *ac)
 	}
 
 	/* DC's ntDSDSA object */
-	if (ldb_dn_compare(ac->req->op.del.dn, samdb_ntds_settings_dn(ldb)) == 0) {
+	if (ldb_dn_compare(ac->req->op.del.dn, samdb_ntds_settings_dn(ldb, ac)) == 0) {
 		ldb_asprintf_errstring(ldb, "objectclass: Cannot delete %s, it's the DC's ntDSDSA object!",
 				       ldb_dn_get_linearized(ac->req->op.del.dn));
 		return LDB_ERR_UNWILLING_TO_PERFORM;
diff --git a/source4/dsdb/samdb/ldb_modules/ridalloc.c b/source4/dsdb/samdb/ldb_modules/ridalloc.c
index 2cef1c445f..915248c440 100644
--- a/source4/dsdb/samdb/ldb_modules/ridalloc.c
+++ b/source4/dsdb/samdb/ldb_modules/ridalloc.c
@@ -407,7 +407,7 @@ static int ridalloc_create_own_rid_set(struct ldb_module *module, TALLOC_CTX *me
 		return ret;
 	}
 
-	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), fsmo_role_dn) != 0) {
+	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb, tmp_ctx), fsmo_role_dn) != 0) {
 		ridalloc_poke_rid_manager(module);
 		ldb_asprintf_errstring(ldb, "Remote RID Set allocation needs refresh");
 		talloc_free(tmp_ctx);
@@ -448,7 +448,7 @@ static int ridalloc_new_own_pool(struct ldb_module *module, uint64_t *new_pool,
 		return ret;
 	}
 
-	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), fsmo_role_dn) != 0) {
+	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb, tmp_ctx), fsmo_role_dn) != 0) {
 		ridalloc_poke_rid_manager(module);
 		ldb_asprintf_errstring(ldb, "Remote RID Set allocation needs refresh");
 		talloc_free(tmp_ctx);
diff --git a/source4/dsdb/samdb/ldb_modules/rootdse.c b/source4/dsdb/samdb/ldb_modules/rootdse.c
index 6859d04e59..9ae5b20eb1 100644
--- a/source4/dsdb/samdb/ldb_modules/rootdse.c
+++ b/source4/dsdb/samdb/ldb_modules/rootdse.c
@@ -197,7 +197,7 @@ static int dsdb_module_we_are_master(struct ldb_module *module, struct ldb_dn *d
 		return LDB_SUCCESS;
 	}
 
-	*master = (ldb_dn_compare(owner_dn, samdb_ntds_settings_dn(ldb_module_get_ctx(module))) == 0);
+	*master = (ldb_dn_compare(owner_dn, samdb_ntds_settings_dn(ldb_module_get_ctx(module), tmp_ctx)) == 0);
 	talloc_free(tmp_ctx);
 	return LDB_SUCCESS;
 }
@@ -1073,7 +1073,7 @@ static int rootdse_enable_recycle_bin(struct ldb_module *module,struct ldb_conte
 	}
 
 	tmp_ctx = talloc_new(mem_ctx);
-	ntds_settings_dn = samdb_ntds_settings_dn(ldb);
+	ntds_settings_dn = samdb_ntds_settings_dn(ldb, tmp_ctx);
 	if (!ntds_settings_dn) {
 		talloc_free(tmp_ctx);
 		return ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR, "Failed to find NTDS settings DN");
diff --git a/source4/dsdb/samdb/ldb_modules/util.c b/source4/dsdb/samdb/ldb_modules/util.c
index 0f1a61236f..253d5c1d2c 100644
--- a/source4/dsdb/samdb/ldb_modules/util.c
+++ b/source4/dsdb/samdb/ldb_modules/util.c
@@ -691,15 +691,16 @@ int dsdb_check_optional_feature(struct ldb_module *module, struct GUID op_featur
 	struct ldb_message_element *el;
 	struct ldb_dn *feature_dn;
 
-	feature_dn = samdb_ntds_settings_dn(ldb_module_get_ctx(module));
+	tmp_ctx = talloc_new(ldb);
+
+	feature_dn = samdb_ntds_settings_dn(ldb_module_get_ctx(module), tmp_ctx);
 	if (feature_dn == NULL) {
+		talloc_free(tmp_ctx);
 		return ldb_operr(ldb_module_get_ctx(module));
 	}
 
 	*feature_enabled = false;
 
-	tmp_ctx = talloc_new(ldb);
-
 	ret = dsdb_module_search_dn(module, tmp_ctx, &res, feature_dn, attrs, DSDB_FLAG_NEXT_MODULE, NULL);
 	if (ret != LDB_SUCCESS) {
 		ldb_asprintf_errstring(ldb,