Syslinux - Mar 2009 - [PATCH 1/1] CORE/writedec: Fix overflow and redeclaration

From: Gene Cumm <gene.cumm at gmail.com>

CORE/writedec: Fix overflow and redeclaration; If EDX is greater than
or equal to 10, div can cause an overflow.  Comment out declaration of
writechr.

Signed-off-by: Gene Cumm <gene.cumm at gmail.com>

---

Against current head.

hpa: If there's a preferred way to do what this function provides, let
me know.  Was the writechr in there on purpose to prevent the use of
this function?


diff --git a/core/writedec.inc b/core/writedec.inc
index 10bf7ba..6101aeb 100644
--- a/core/writedec.inc
+++ b/core/writedec.inc
@@ -37,7 +37,8 @@ writedec_common:
                xor cx,cx               ; Number of digits

 .cloop:
-               div ebx
+               mov edx,0               ; Zero out high part
+               div ebx                 ; unsigned divide edx:eax/ebx
                inc cx
                push dx
                and eax,eax
@@ -53,5 +54,5 @@ writedec_common:
                popad
                ret

-writechr:
-               ret
+; writechr:
+;              ret

Gene Cumm wrote:
> From: Gene Cumm <gene.cumm at gmail.com>
> 
> CORE/writedec: Fix overflow and redeclaration; If EDX is greater than
> or equal to 10, div can cause an overflow.  Comment out declaration of
> writechr.
> 
> Signed-off-by: Gene Cumm <gene.cumm at gmail.com>
> 
> ---
> 
> Against current head.
> 
> hpa: If there's a preferred way to do what this function provides, let
> me know.  Was the writechr in there on purpose to prevent the use of
> this function?
> 
No, it was just never actually tested since there was no user for it.

	-hpa