Subject: Re: [PATCH v4] kptr_restrict for hiding kernel pointers

From: Dan Rosenberg <[email-masked]>
Date: Wed, 22 Dec 2010 08:13:09 -0500

> Hm, why is it off by default? Is there some user-space regression that is caused by 
> this?
> 
> We really want good security measures to be active by default (and to work by 
> default) - they are not worth much if they are not.
> 

I agree entirely, but I've received a lot of resistance to these types
of changes in net.  I'm afraid that if it's enabled by default, no one
will actually allow use of the %pK specifier where it should be used.

As far as I know, there's no actual breakage of anything in userspace,
but there's a general "it might make it harder to debug things in
certain limited circumstances" sentiment among some.  I never understood
why it is necessary for unprivileged users to be able to debug the
kernel.

Does anyone else have thoughts on this?

> Thanks,
> 	Ingo