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ManOfSteel



Joined: 02 Feb 2005
Posts: 1154
ManOfSteel
Hello,
I would like to know what is returned in eax after the final subtraction. Is it the address of the Addr3 label? I just want to be sure.
thanks.

Code:
        call    Addr2
Addr1:
<some code>
Addr2:  pop     eax
        sub     eax,(Addr1 - Addr3)

<some code>

Addr3:
    
Post 07 Oct 2006, 09:49
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17348
Location: In your JS exploiting you and your system
revolution
Quote:
I would like to know what is returned in eax after the final subtraction.
You get: (Addr1 - (Addr1 - Addr3) ) = Addr3.
Post 07 Oct 2006, 10:06
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ManOfSteel



Joined: 02 Feb 2005
Posts: 1154
ManOfSteel
Ok, thanks. Just what I thought. So basically, one could just use the Addr3 label automatically instead of doing these computations, right?

like:

Code:
Addr3:
        mov    byte [Addr3],'w'
    


instead of:

Code:
        call    Addr2 
Addr1: 
<some code> 
Addr2:  pop     eax 
        sub     eax,(Addr1 - Addr3) 

<some code> 

Addr3:

mov byte [eax],'w'
    
Post 07 Oct 2006, 10:44
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17348
Location: In your JS exploiting you and your system
revolution
Quote:
one could just use the Addr3 label automatically
Yes
Post 07 Oct 2006, 11:00
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