[PATCH] Fix failure to update dirpath

[Anoop C S]

On Mon, 2018-08-20 at 18:35 -0700, Jeremy Allison wrote:
> On Mon, Aug 20, 2018 at 06:02:31PM -0700, Jeremy Allison via samba-technical wrote:
> > 
> > Hang on a minute. I've been looking really closely
> > now at the *callers* of check_parent_exists() and
> > many of them depend on *dirpath == '\0' in the
> > case where smb_fname->base_name doesn't contain
> > a component containing '/' characters.
> > 
> > I think my fix, although it might work, will affect
> > other paths. Let me look at this more closely
> > tomorrow. I'm withdrawing this for now.
> 
> OK, my fix was way too invasive for the fix that
> you need to make Gluster work again for that bug.
> 
> The problem is that the code that constructs
> the complete pathname depends on *dirpath == '\0'
> to avoid adding a "./" prefix to every constructed
> pathname. My patch would cause all of those
> code paths to change to the full/component/path
> cases, which is not what we want. That's going
> to affect what goes into the stat-cache as well
> as many other things I'll have to go through
> carefully to find.

Ok.

> This is a set of code-paths that we might clean
> up in the future, but not for this specific bug
> I think.
> 
> Can you test the following change instead ?

The attached diff also works.

> Much simpler and I think it will fix the immediate
> Gluster problem (it's the same change that already
> exists inside get_real_filename_full_scan() so
> I think this is something we already ran across
> there).

Considering the fact that we are not 100% sure about the side effects of previous fix which was more
aggressive, the current solution is more clean and elegant. In addition to that the presence of same
statements inside get_real_filename_full_scan(), which is a fallback, gives us more confidence to
fix it here.

I hope you you will be attaching the diff as a patch to other thread for review.

> Thanks,
> 
> Jeremy.