diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
index 0d97377..50bc105 100644
--- a/lib/efi_loader/efi_variable.c
+++ b/lib/efi_loader/efi_variable.c
@@ -451,12 +451,21 @@
 	if (val) {
 		parse_attr(val, &attr);
 
+		/* We should not free val */
+		val = NULL;
 		if (attr & READ_ONLY) {
-			/* We should not free val */
-			val = NULL;
 			ret = EFI_WRITE_PROTECTED;
 			goto out;
 		}
+
+		/*
+		 * attributes won't be changed
+		 * TODO: take care of APPEND_WRITE once supported
+		 */
+		if (attr != attributes) {
+			ret = EFI_INVALID_PARAMETER;
+			goto out;
+		}
 	}
 
 	val = malloc(2 * data_size + strlen("{ro,run,boot}(blob)") + 1);