Re: [PATCH 0/2] mm: introduce MAP_FIXED_SAFE

From: Michal Hocko
Date: Thu Nov 30 2017 - 01:58:48 EST


On Wed 29-11-17 14:25:36, Kees Cook wrote:
> On Wed, Nov 29, 2017 at 6:42 AM, Michal Hocko <mhocko@xxxxxxxxxx> wrote:
> > The first patch introduced MAP_FIXED_SAFE which enforces the given
> > address but unlike MAP_FIXED it fails with ENOMEM if the given range
> > conflicts with an existing one. The flag is introduced as a completely
>
> I still think this name should be better. "SAFE" doesn't say what it's
> safe from...

It is safe in a sense it doesn't perform any address space dangerous
operations. mmap is _inherently_ about the address space so the context
should be kind of clear.

> MAP_FIXED_UNIQUE
> MAP_FIXED_ONCE
> MAP_FIXED_FRESH

Well, I can open a poll for the best name, but none of those you are
proposing sound much better to me. Yeah, naming sucks...
--
Michal Hocko
SUSE Labs