From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ben Hutchings <ben-/+tVBieCtBitmTQ+vhA3Yw@public.gmane.org>
Subject: Re: [PATCH 15/24] asus-wmi: Restrict debugfs interface when the
 kernel is locked down
Date: Tue, 18 Apr 2017 18:39:18 +0100
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To: David Howells <dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
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On Tue, 2017-04-18 at 16:30 +0100, David Howells wrote:
> Ben Hutchings <ben-/+tVBieCtBitmTQ+vhA3Yw@public.gmane.org> wrote:
>=20
> > So it's generally not going to be OK to turn off debugfs.=C2=A0=C2=A0Th=
ere will
> > probably need to be a distinction between believed-safe and unsafe
> > directories/files.
>=20
> Any suggestion on how to mark this distinction?

I don't know.

> I'd prefer not to modify every read/write op associated with a
> debugfs file.

I think debugfs should be assumed unsafe by default.  So only the
believed-safe parts would need to be changed.

> Modify
> DEFINE_DEBUGFS_ATTRIBUTE() maybe?=C2=A0=C2=A0And provide lockable variant=
s of
> debugfs_create_u8() and co.?

That could help.

Ben.

--=20
Ben Hutchings
The world is coming to an end.	Please log off.


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