Subject: Re: [PATCH] ubifs: Fix O_TMPFILE corner case in ubifs_link()
To: Amir Goldstein <amir73il@gmail.com>
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Cc: Adrian Hunter <adrian.hunter@intel.com>, linux-mtd@lists.infradead.org,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Artem Bityutskiy <dedekind1@gmail.com>,
        "stable [v4.9]" <stable@vger.kernel.org>,
        Ralph Sennhauser <ralph.sennhauser@gmail.com>
From: Richard Weinberger <richard@nod.at>
Message-ID: <54320a7a-5022-732f-5a5d-5ec4ca5a4d9e@nod.at>
Date: Thu, 30 Mar 2017 12:51:27 +0200
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Amir,

Am 30.03.2017 um 12:35 schrieb Amir Goldstein:
>> Reading deeper into the proved that I was wrong.
>> AFAIKT UBIFS' journal has currently no way to revive a deleted inode.
>> So, we have to think about a new solution.
>>
> 
> Not that I know anything about ubifs, but why do you need the deleted
> inode record in the first place for an O_TMPFILE.
> vfs ensures you that you can only link back an O_TMPFILE, not a deleted
> inode.
> 
> It does not appear to be the right thing to do to pass deletion=1 to
> ubifs_jnl_update(), but deletion=0 doesn't look right as well..

We need to think of a new case.
I choose deletion=1 to ensure that after a power-cut written data of the
tmpfile gets removed.

Thanks,
//richard