RE: [PATCH v7 0/7] Add support for O_MAYEXEC

David Laight
2020-08-11T08:09:36Z

> On 11/08/2020 00:28, Al Viro wrote:
> > On Mon, Aug 10, 2020 at 10:09:09PM +0000, David Laight wrote:
> >>> On Mon, Aug 10, 2020 at 10:11:53PM +0200, Mickaël Salaün wrote:
> >>>> It seems that there is no more complains nor questions. Do you want me
> >>>> to send another series to fix the order of the S-o-b in patch 7?
> >>>
> >>> There is a major question regarding the API design and the choice of
> >>> hooking that stuff on open(). And I have not heard anything resembling
> >>> a coherent answer.
> >>
> >> To me O_MAYEXEC is just the wrong name.
> >> The bit would be (something like) O_INTERPRET to indicate
> >> what you want to do with the contents.
>
> The properties is "execute permission". This can then be checked by
> interpreters or other applications, then the generic O_MAYEXEC name.

The english sense of MAYEXEC is just wrong for what you are trying
to check.

> > ... which does not answer the question - name of constant is the least of
> > the worries here. Why the hell is "apply some unspecified checks to
> > file" combined with opening it, rather than being an independent primitive
> > you apply to an already opened file? Just in case - "'cuz that's how we'd
> > done it" does not make a good answer...

Maybe an access_ok() that acts on an open fd would be more
appropriate.
Which might end up being an fcntrl() action.
That would give you a full 32bit mask of options.

David

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