diff --git a/vm/os-genunix.cpp b/vm/os-genunix.cpp
index 08893f3889..21b9304e40 100644
--- a/vm/os-genunix.cpp
+++ b/vm/os-genunix.cpp
@@ -20,8 +20,8 @@ const char* default_image_path() {
     return "factor.image";
 
   int len = strlen(path);
-  char* new_path = new char[PATH_MAX + SUFFIX_LEN + 1];
-  memcpy(new_path, path, len + 1);
+  char* new_path = new char[len + SUFFIX_LEN + 1];
+  memcpy(new_path, path, len);
   memcpy(new_path + len, SUFFIX, SUFFIX_LEN + 1);
   free(const_cast<char*>(path));
   return new_path;