diff --git a/src/filo-fs-ext2.adb b/src/filo-fs-ext2.adb
index 3f82377..7cf6147 100644
--- a/src/filo-fs-ext2.adb
+++ b/src/filo-fs-ext2.adb
@@ -517,7 +517,7 @@
 
       Success :=
          Length > 0 and then
-         Logical_Off <= FSBlock_Logical'Last - Length + 1 and then
+         Logical_Off <= FSBlock_Logical'Last - Length and then
          Logical < Logical_Off + Length;
       if Success then
          Physical := Physical + FSBlock_Offset (Logical - Logical_Off);