Re: Shellcode jmp problem

[Claes Nyberg <md0claes () mdstud chalmers se>]

It's not really the same instruction, compare the first byte
"\xe9" and "\xeb". Use the instruction reference to look up the
difference (http://www.mdstud.chalmers.se/~md0claes/IntelInstrSet.pdf)
:-)

You could also push the string onto the stack and save the
value of esp, since that's the address to your string.

pushl   $0x68732f2f # 'hs//' (Little endian)
pushl   $0x6e69622f # 'nib/'
movl    %esp,%ebx   # Address to pushed string saved in ebx


// CMN


On Thu, 16 Oct 2003, Darragh O'Brien wrote:

> Hi,
>
> I'm having trouble trying to recreate Aleph One's shellcode.
>
> My initial jmp generates 5 bytes \xe9\x19\x00\x00\x00 but
> Aleph One's jmp only generates two \xeb\x19 - I'd be
> grateful if someone could tell me where I'm going wrong.
>
> Thanks,
> Darragh
>
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