[PATCH] ubifs: Fix O_TMPFILE corner case in ubifs_link()

[Ralph Sennhauser]

On Tue, 11 Apr 2017 18:04:50 +0300
Amir Goldstein <amir73il at gmail.com> wrote:

> On Tue, Apr 11, 2017 at 1:50 PM, Richard Weinberger <richard at nod.at>
> wrote:
> > Hi!
> >
> > Am 11.04.2017 um 12:20 schrieb Amir Goldstein:  
> >> On Thu, Apr 6, 2017 at 3:26 PM, Richard Weinberger
> >> <richard at nod.at> wrote:  
> >>> Am 06.04.2017 um 14:09 schrieb Richard Weinberger:  
> >>>>> Were you able to make any progress? still working on this?
> >>>>> If this is too complicated to get in for this cycle, better
> >>>>> send a patch to disable O_TMPFILE support for ubifs and fix the
> >>>>> problem properly on followup merge cycle.
> >>>>> Because right now ubifs O_TMPFILE support is broken and breaks
> >>>>> overlayfs mount.  
> >>>>
> >>>> I have a test and currently testing it. As it looks the
> >>>> situation is less worse than I thought first. :-)  
> >>>
> >>> s/test/patch :)
> >>>  
> >>
> >> Richard,
> >>
> >> Maybe it's not my business to interfere with ubifs development and
> >> I haven't seen your patch.
> >>
> >> But on the face of it, it doesn't sound like fixing O_TMPFILE is a
> >> trivial fix, so not sure
> >> it is wise to send a patch for -rc7?...
> >>
> >> How about sending the patch to disable O_TMPFILE for -rc7 and
> >> queuing your fix for v4.12?
> >> Without any patch, v4.11 is going to have a regression with
> >> overlayfs+ubifs.  
> >
> > No need to panic.  
> 
> Who? me?  ;-)
> 
> > I verified some stuff and my first patch does the right thing but
> > not in a nice way, except in oneerror patch. In will land in -rc7.
> >  

Hi Amir, Richard

Looks like the fix didn't make it into 4.11-rc7 either, isn't it time
to just disable O_TMPFILE support in ubifs for now? Giving plenty
time for the proper fix.

Thanks
Ralph

> 
> That patch looks simple enough.
> I though you had a more complex patch in mind.
> 
> > For the next merge window I prepare patches that introduce a new
> > journal function for handling tmpfiles.
> >  
> 
> Thanks for the update.
> Cheers,
> Amir.