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Date:   Sat, 28 Aug 2021 09:10:14 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     NeilBrown <neilb@suse.de>
Cc:     Christoph Hellwig <hch@lst.de>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        David Howells <dhowells@redhat.com>,
        torvalds@linux-foundation.org, trond.myklebust@primarydata.com,
        linux-nfs@vger.kernel.org, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Don't block writes to swap-files with ETXTBSY.
Message-ID: <20210828071014.GA31677@lst.de>
References: <20210827151644.GB19199@lst.de> <163010581548.7591.7557563272768619093@noble.neil.brown.name>
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On Sat, Aug 28, 2021 at 09:10:15AM +1000, NeilBrown wrote:
> There are lots of different things root can do which will mess up the
> kernel badly.  The backing-store can still be changed through some other
> means.
> Do you have a particular threat or risk scenario other than "root might
> get careless"?

No, it is just that scenario.  But one that is much easier to trigger
than more convoluted ways for a root user to trigger damage through
device files, and one that can't be prevented through LSMs or the
capability system.