Re: [PATCH] LSM: Make security_hook_heads a local variable.

From: Tetsuo Handa
Date: Mon May 22 2017 - 16:44:32 EST


Casey Schaufler wrote:
> On 5/22/2017 12:50 PM, Igor Stoppa wrote:
> > On 22/05/17 18:09, Casey Schaufler wrote:
> >> On 5/22/2017 7:03 AM, Christoph Hellwig wrote:
> > [...]
> >
> >>> But even with those we can still chain
> >>> them together with a list with external linkage.
> >> I gave up that approach in 2012. Too many unnecessary calls to
> >> null functions, and massive function vectors with a tiny number
> >> of non-null entries. From a data structure standpoint, it was
> >> just wrong. The list scheme is exactly right for the task at
> >> hand.
> > I understand this as a green light, for me to continue with the plan of
> > using LSM Hooks as example for making dynamically allocated data become
> > read-only, using also Tetsuo's patch (thanks, btw).
>
> I still don't like the assumption that a structure of
> N elements can be assumed to be the same as an array
> of N elements.

I think we can use "enum" and call via index numbers while preserving
current "union" for type checking purpose.