Re: CVS commit: src

[Jean-Yves Migeon <jym%NetBSD.org@localhost>]

On 20.12.2011 16:39, Reinoud Zandijk wrote:
> Module Name:    src
> Committed By:   reinoud
> Date:           Tue Dec 20 15:39:36 UTC 2011
>
> Modified Files:
>         src/lib/libc/sys: mmap.2
>         src/sys/sys: mman.h proc.h
>         src/sys/uvm: uvm_extern.h uvm_map.c uvm_mmap.c
>
> Log Message:
> Add a MAP_NOSYSCALLS flag to mmap. This flag prohibits executing of system
> calls from the mapped region. This can be used for emulation perposed or for
> extra security in the case of generated code.

IMHO, this change should have been discussed first.

Can you please elaborate on its usage? I fail to see the point about 
emulation, and even more so about the alleged extra security where this 
can be trivially bypassed. Return to libfoo and ROP are quite mainstream 
techniques these days...

--
Jean-Yves Migeon
jym%NetBSD.org@localhost