Re: [PATCH v2 1/3] module: verify address is read-only

[Stephen Hemminger]

On Tue, 21 Feb 2017 12:32:16 -0800
Kees Cook <keescook@xxxxxxxxxxxx> wrote:

> On Mon, Feb 20, 2017 at 9:14 AM, Stephen Hemminger
> <stephen@xxxxxxxxxxxxxxxxxx> wrote:
> > On Fri, 17 Feb 2017 21:58:42 -0800
> > "Eddie Kovsky" <ewk@xxxxxxxxxxxx> wrote:
> >  
> >> Implement a mechanism to check if a module's address is in
> >> the rodata or ro_after_init sections. It mimics the exsiting functions
> >> that test if an address is inside a module's text section.
> >>
> >> Signed-off-by: Eddie Kovsky <ewk@xxxxxxxxxxxx>  
> >
> > I don't see the point of this for many of the hyper-v functions.
> > They are only called from a small number of places, and this can be validated
> > by code inspection. Adding this seems just seems to be code bloat to me.  
> 
> I think it has value in that it effectively blocks any way for
> non-ro_after_init structures from being passed into these functions.
> Since there are so few callers now, it's the perfect place to add
> this.
> 
> -Kees
> 

Maybe for a more used API, but for such a corner case it is code bloat.