Re: [Question] Status of user-space dynamic overlays API

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Ayush,

On Sat, 22 Feb 2025 at 21:14, Ayush Singh <ayush@beagleboard.org> wrote:
> # Challenges
>
> ## Security
>
> The concerns regarding security seemed to show up in the other
> proposals. There was a proposal to have a devicetree property to
> allow/deny the application of overlays in some nodes, with default being
> deny. Was it insufficient?

This is the most important issue: using DT overlays, you can change
about anything.  There is no protection yet to limit this to e.g. the
expansion connectors on your board.
This is what the various WIP "connector" abstractions are trying
to solve.

> ## Memory Leaks
>
> Currently, updating/removing properties leaks memory. Was it one of the
> reasons for the rejection of previous proposals?

IMO this is a minor issue. I am sure this can be improved upon.  We just
need some way to keep track of which properties are part of the initial
FDT (and thus can't be freed), and which were allocated dynamically.

> [0]:
> https://lore.kernel.org/all/1417605808-23327-1-git-send-email-pantelis.antoniou@konsulko.com/#t

FTR, I do keep this up to date:
https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/log/?h=topic/overlays

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds