Re: [PATCH] fs/proc/kcore.c: Omit kernel text area for hardened usercopy feature

[Andi Kleen]

On Tue, Sep 06, 2016 at 11:34:28AM -0700, Linus Torvalds wrote:
> On Tue, Sep 6, 2016 at 10:56 AM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> >
> > In the meantime, how about continuing to use a bounce buffer like
> > already done in the vmalloc_or_module_addr() case immediately above?
> 
> Yes please. Let's not make up even more of the user access functions
> with magical properties, for some special-case code in /proc/kcore.

I suspect it's more than just /proc/kcore, there could be also 
legitimate cases to read kernel text from /dev/mem or /dev/kmem

I suppose could add bounce buffers everywhere.

-Andi