1.70.01 fails on lea ecx,[$3fff+64-$3fff-(not 30 + 32)]

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revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20667
Location: In your JS exploiting you and your system

revolution 06 Jul 2012, 12:55

It makes me wince to see this effect:

Code:

use16
x = not 0
lea ecx,[eax+not 0]   ;lea ecx,[eax+0xFFFF]
lea ecx,[eax+x]                ;lea ecx,[eax+0xFFFFFFFF]

06 Jul 2012, 12:55

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8428
Location: Kraków, Poland

Tomasz Grysztar 06 Jul 2012, 13:05

As the default context for address here is 16-bit, you get the result as if you defined x this way:

Code:

x = word not 0

It is pretty straightforward, even if unexpected (at least until you know how it works).

06 Jul 2012, 13:05

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