diff --git a/core/src/fxge/ge/fx_ge_fontmap.cpp b/core/src/fxge/ge/fx_ge_fontmap.cpp
index af0a9ef..4f627ac 100644
--- a/core/src/fxge/ge/fx_ge_fontmap.cpp
+++ b/core/src/fxge/ge/fx_ge_fontmap.cpp
@@ -1510,8 +1510,10 @@
     }
   }
   if (datasize && size >= datasize && pFile) {
-    FXSYS_fseek(pFile, offset, FXSYS_SEEK_SET);
-    FXSYS_fread(buffer, datasize, 1, pFile);
+    if (FXSYS_fseek(pFile, offset, FXSYS_SEEK_SET) < 0 ||
+        FXSYS_fread(buffer, datasize, 1, pFile) != 1) {
+      datasize = 0;
+    }
   }
   if (pFile) {
     FXSYS_fclose(pFile);