diff --git a/source4/auth/gensec/gensec.c b/source4/auth/gensec/gensec.c
index 429aa433d70..2d347b65b1c 100644
--- a/source4/auth/gensec/gensec.c
+++ b/source4/auth/gensec/gensec.c
@@ -87,8 +87,9 @@ struct gensec_security_ops **gensec_use_kerberos_mechs(TALLOC_CTX *mem_ctx,
 				j++;
 			}
 			break;
-		case CRED_AUTO_USE_KERBEROS:
-			break;
+		default:
+			/* Can't happen or invalid parameter */
+			return NULL;
 		}
 	}
 	new_gensec_list[j] = NULL; 
diff --git a/source4/dsdb/samdb/ldb_modules/password_hash.c b/source4/dsdb/samdb/ldb_modules/password_hash.c
index 9d7c78487ab..abb267d8846 100644
--- a/source4/dsdb/samdb/ldb_modules/password_hash.c
+++ b/source4/dsdb/samdb/ldb_modules/password_hash.c
@@ -597,7 +597,7 @@ static int password_hash_add(struct ldb_module *module, struct ldb_request *req)
 
 	/* check sambaPassword is single valued here */
 	/* TODO: remove this when sambaPassword will be single valued in schema */
-	if (sambaAttr->num_values > 1) {
+	if (sambaAttr && sambaAttr->num_values > 1) {
 		ldb_set_errstring(module->ldb, 
 				  talloc_asprintf(req,
 						  "mupltiple values for sambaPassword not allowed!\n"));
diff --git a/source4/lib/ldb/common/ldb_dn.c b/source4/lib/ldb/common/ldb_dn.c
index a659f676c6d..0d7a3c61417 100644
--- a/source4/lib/ldb/common/ldb_dn.c
+++ b/source4/lib/ldb/common/ldb_dn.c
@@ -578,32 +578,35 @@ struct ldb_dn *ldb_dn_casefold(struct ldb_context *ldb, const struct ldb_dn *edn
 	if (edn == NULL) return NULL;
 
 	cedn = ldb_dn_new(ldb);
-	LDB_DN_NULL_FAILED(cedn);
+	return NULL;
 
 	cedn->comp_num = edn->comp_num;
 	cedn->components = talloc_array(cedn, struct ldb_dn_component, edn->comp_num);
-	LDB_DN_NULL_FAILED(cedn->components);
+	if (!cedn->components) {
+		talloc_free(cedn);
+		return NULL;
+	}
 
 	for (i = 0; i < edn->comp_num; i++) {
 		struct ldb_dn_component dc;
 		const struct ldb_attrib_handler *h;
 
 		dc.name = ldb_attr_casefold(cedn, edn->components[i].name);
-		LDB_DN_NULL_FAILED(dc.name);
+		if (!dc.name) {
+			talloc_free(cedn);
+			return NULL;
+		}
 
 		h = ldb_attrib_handler(ldb, dc.name);
 		if (h->canonicalise_fn(ldb, cedn, &(edn->components[i].value), &(dc.value)) != 0) {
-			goto failed;
+			talloc_free(cedn);
+			return NULL;
 		}
 
 		cedn->components[i] = dc;
 	}
 
 	return cedn;
-
-failed:
-	talloc_free(cedn);
-	return NULL;
 }
 
 struct ldb_dn *ldb_dn_explode_casefold(struct ldb_context *ldb, const char *dn)