tech-userlevel: Re: Code on stack (Re: exploit with memcpy())

Subject: Re: Code on stack (Re: exploit with memcpy())
To: TAMURA Kent <kent@netbsd.org>
From: Noriyuki Soda <soda@sra.co.jp>
List: tech-userlevel
Date: 07/04/2002 13:59:30

>>>>> On Thu,  4 Jul 2002 13:50:12 +0900 (JST),
	TAMURA Kent <kent@netbsd.org> said:

> To prohibit calling syscalls from stack code would be sufficient.

It might help a bit, but it is not sufficient.
Once intruder gain control, he can copy code fragment to data segment,
and he can jump to the copied code in data area.
--
soda