diff --git a/ChangeLog b/ChangeLog
index 2ffbbcd7b..612669367 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2010-08-28  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/script/lexer.c (grub_script_lexer_init): Don't look before
+	the begining of the string
+
 2010-08-28  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/script/script.c (grub_script_parse): Free parsed on
diff --git a/grub-core/script/lexer.c b/grub-core/script/lexer.c
index 42a570348..64da45ed8 100644
--- a/grub-core/script/lexer.c
+++ b/grub-core/script/lexer.c
@@ -236,7 +236,7 @@ grub_script_lexer_init (struct grub_parser_param *parser, char *script,
   script = script ? : "\n";
   len = grub_strlen (script);
 
-  if (script[len - 1] == '\n')
+  if (len != 0 && script[len - 1] == '\n')
     {
       buffer = yy_scan_string (script, lexerstate->yyscanner);
     }