diff --git a/src/core/dmi.cc b/src/core/dmi.cc
index ced891a..e89ff93 100644
--- a/src/core/dmi.cc
+++ b/src/core/dmi.cc
@@ -1833,6 +1833,8 @@ static bool scan_dmi_sysfs(hwNode & n)
   ifstream ep_stream(SYSFSDMI "/smbios_entry_point",
       ifstream::in | ifstream::binary | ifstream::ate);
   ifstream::pos_type ep_len = ep_stream.tellg();
+  if (ep_len == -1)
+    return false;
   vector < u8 > ep_buf(ep_len);
   ep_stream.seekg(0, ifstream::beg);
   ep_stream.read((char *)ep_buf.data(), ep_len);