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Date:   Wed, 20 Oct 2021 16:29:07 -0400
From:   Bruce Fields <bfields@fieldses.org>
To:     dai.ngo@oracle.com
Cc:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Steve Dickson <steved@redhat.com>,
        Olga Kornievskaia <olga.kornievskaia@gmail.com>,
        Chuck Lever <chuck.lever@oracle.com>
Subject: Re: server-to-server copy by default
Message-ID: <20211020202907.GF597@fieldses.org>
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On Wed, Oct 20, 2021 at 12:03:46PM -0700, dai.ngo@oracle.com wrote:
> 
> On 10/20/21 9:33 AM, Olga Kornievskaia wrote:
> >On Wed, Oct 20, 2021 at 12:00 PM Chuck Lever III <chuck.lever@oracle.com> wrote:
> >>>2. Security question: with server-to-server copy enabled, you can send
> >>>the server a COPY call with any random address, and the server will
> >>>mount that address, open a file, and read from it.  Is that safe?
> 
> The client already has write access to the share on the destination
> server, it can write any data to the destination file.

Agreed.  Please look back at what I said; I'm not thinking about attacks
on the source server, I'm thinking about attacks on the destination (the
one that receives the COPY).

--b.