Re: [PATCH 1/3] kernel/sysctl: support setting sysctl parameters from kernel command line

Kees Cook
2020-03-31T18:26:56Z

On Tue, Mar 31, 2020 at 09:48:36AM +0200, Michal Hocko wrote:
> On Tue 31-03-20 09:42:46, Vlastimil Babka wrote:
> [...]
> > > Should we not do this, we'll have to live with the consequences of
> > > supporting the full swoop of sysctls are boot params, whatever
> > > consequences those may be.
> >
> > Of course when the first user tries to set some particular sysctl as boot param
> > and finds and reports it doesn't work as intended, then it can be fixed or
> > blacklisted and it can't break anyone else?
>
> Absolutely agreed. I would be really careful to not overengineer this
> whole thing.

Right -- this is supposed to be _simple_, and I think that's the primary
benefit here. If we encounter problems we can fix those cases. The
careful place, I think, needs to be with converting existing boot params
to be aliases. That's when timing considerations need to be taken into
account carefully.

--
Kees Cook