[syslinux:master] core: When checking for DS:SI validity, we're using paragraph units

[syslinux-bot for H. Peter Anvin]

Commit-ID:  102b58a9960667208a2f37ca6058b9badad67111
Gitweb:     http://syslinux.zytor.com/commit/102b58a9960667208a2f37ca6058b9badad67111
Author:     H. Peter Anvin <hpa at zytor.com>
AuthorDate: Sun, 20 Feb 2011 16:27:18 -0800
Committer:  H. Peter Anvin <hpa at zytor.com>
CommitDate: Sun, 20 Feb 2011 16:27:18 -0800

core: When checking for DS:SI validity, we're using paragraph units

We are comparing DS:SI for a sane range, but we're operating in
paragraph units, so the comparison needs to be done that way, too.

Reported-by: Keshav P.R. <skodabenz at gmail.com>
Debugged-by: Michal Soltys <soltys at ziu.info>
Signed-off-by: H. Peter Anvin <hpa at zytor.com>


---
 core/diskboot.inc |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/core/diskboot.inc b/core/diskboot.inc
index 7c02066..1be6ade 100644
--- a/core/diskboot.inc
+++ b/core/diskboot.inc
@@ -1,7 +1,7 @@
 ; -----------------------------------------------------------------------
 ;
 ;   Copyright 1994-2009 H. Peter Anvin - All Rights Reserved
-;   Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin
+;   Copyright 2009-2011 Intel Corporation; author: H. Peter Anvin
 ;
 ;   This program is free software; you can redistribute it and/or modify
 ;   it under the terms of the GNU General Public License as published by
@@ -185,7 +185,7 @@ harddisk:
 		shr si,4
 		jz .no_partition	; SI == 0 -> assume no partition
 		add dx,si
-		cmp dx,1024		; DS:SI < 1K (inside the IVT)?
+		cmp dx,1024 >> 4	; DS:SI < 1K (inside the IVT)?
 		jb .no_partition
 		cmp dx,PartInfo >> 4	; DS:SI in overwritten memory?
 		jae .no_partition