Re: hello again :D

Hi,

Yes, you cannot write to code memory, it will be read only.
what you could do is write a dummy function, call it and overwrite
the return address on the stack, which is in data memory to return to
a different place
ie, after t1.
IIRC, that will be 4(2?) bytes below top of stack in the function,
after the frame pointer.

mov (sp - 1), bye;
ret ;

might work ?? opinions ???

regards,

Joy
>
> section .text
>         global _start
>
> _start:
>         xor ebx, ebx
>         mov byte [t1], 0x90
>
> t1:
>         inc ebx ; try to skip this so exit(0) instead of exit(1);
>
> bye:
>         xor eax, eax
>         inc eax
>         int 80h
>
> i figured that since an "inc" is 1 byte, mov byte [t1], 90h will do the trick. if the nop was succesful, the proggie would have returned a zero exit status instead of one.
> thanks for your help.
>
> tidings,
> - niel
> -
> To unsubscribe from this list: send the line "unsubscribe linux-assembly" in
> the body of a message to [email protected]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


--
Only time will tell, but are we listening ? :)