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Date:   Tue, 29 Mar 2022 11:11:41 -0400
To:     Chuck Lever III <chuck.lever@oracle.com>
Cc:     Neil Brown <neilb@suse.de>,
        Benjamin Coddington <bcodding@redhat.com>,
        Steve Dickson <SteveD@RedHat.com>,
        Trond Myklebust <trondmy@hammerspace.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH/RFC] NFSv4: ensure different netns do not share
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From:   bfields@fieldses.org (J. Bruce Fields)
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On Mon, Mar 28, 2022 at 02:08:31PM +0000, Chuck Lever III wrote:
> Note also that the protocol allows a CLID_INUSE response to return
> the IP address of the conflicting client, but NFSD doesn't do that,
> I guess as a security measure.

The information disclosure sounds mild and not too surprising--mountd
already hands out information about v2/v3 clients (used by "showmount").

Chances are we just didn't get around to it.  If it'd help debug this
kind of problem, I think it'd be worth it.

--b.