diff --git a/src/sourcefs.c b/src/sourcefs.c
index fe6766d..b34fa8b 100644
--- a/src/sourcefs.c
+++ b/src/sourcefs.c
@@ -60,7 +60,7 @@ int source_symlink(const char *target, const char *linkpath) {
 
 DIR *source_opendir(const char *filename) {
   const char *relative_filename = source_filename_translate(filename);
-  int fd = openat(handle.root_fd, relative_filename, NULL);
+  int fd = openat(handle.root_fd, relative_filename, 0);
   if (fd < 0) {
     perror("Openat failed");
     return NULL;
@@ -97,7 +97,7 @@ int source_chown(const char *filename, uid_t owner, gid_t group) {
 
 int source_truncate(const char *filename, off_t length) {
   const char *relative_filename = source_filename_translate(filename);
-  int fd = openat(handle.root_fd, relative_filename, NULL);
+  int fd = openat(handle.root_fd, relative_filename, 0);
   if (fd < 0) {
     perror("Openat failed");
     return -1;