Re: [GIT PULL] SCSI fixes for 4.18-rc3

[Jann Horn]

On Mon, Jul 9, 2018 at 5:41 PM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Fri, Jul 6, 2018 at 10:22 PM James Bottomley
> <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > We did discuss removing the r/w interface, but, as you say, it's been
> > around for ages so it's not clear what regressions would surface if we
> > did.
>
> So since nobody else followed up on this, the attached patch is what I
> was thinking of just committing.
>
> It removes the warnings from the access check, and just puts them
> (unconditionally) at the top of the read/write function instead.
>
> Hmm?

Random unimportant nitpickery:

AFAICS it does mean that if two processes use /dev/sg* - the first one
in a way that passes sg_check_file_access(), the second one in a way
that gets blocked for whatever reason -, the pr_err_once() will fire
for the process that's working and not fire for the one that got
blocked. But if nobody should be using that interface anyway, I guess
that's not a practical concern.

Also, the device is called /dev/sg%d with %d being sdp->index.