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Date:   Mon, 26 Aug 2019 09:39:51 -0400
From:   "J. Bruce Fields" <bfields@fieldses.org>
To:     Alex Lyakas <alex@zadara.com>
Cc:     chuck.lever@oracle.com, linux-nfs@vger.kernel.org,
        Shyam Kaushik <shyam@zadara.com>
Subject: Re: [RFC-PATCH] nfsd: when unhashing openowners, increment
 openowner's refcount
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On Sun, Aug 25, 2019 at 01:12:34PM +0300, Alex Lyakas wrote:
> You are listed as maintainers of nfsd. Can you please take a look at
> the below patch?

Thanks!

I take it this was found by some kind of code analysis or fuzzing, not
use in production?

Asking because I've been considering just deprecating it, so:

> > After we fixed this, we confirmed that the openowner is not freed
> > prematurely. It is freed by release_openowner() final call
> > to nfs4_put_stateowner().
> >
> > However, we still get (other) random crashes and memory corruptions
> > when nfsd_inject_forget_client_openowners() and
> > nfsd_inject_forget_openowners().
> > According to our analysis, we don't see any other refcount issues.
> > Can anybody from the community review these flows for other potentials issues?

I'm wondering how much effort we want to put into tracking all that
down.

--b.