From: Sasha Levin <sashal@kernel.org>
To: Eric Sandeen <sandeen@sandeen.net>
Cc: xfs <linux-xfs@vger.kernel.org>,
stable@vger.kernel.org, gregkh@linuxfoundation.org
Subject: Re: [PATCH STABLE V2] xfs: trim IO to found COW extent limit
Date: Fri, 2 Oct 2020 19:17:18 -0400 [thread overview]
Message-ID: <20201002231718.GH2415204@sasha-vm> (raw)
In-Reply-To: <300427ae-6135-29cd-6cbe-8fa2c4efb8d5@sandeen.net>
On Fri, Oct 02, 2020 at 08:19:43AM -0500, Eric Sandeen wrote:
>On 10/2/20 8:07 AM, Sasha Levin wrote:
>> On Thu, Oct 01, 2020 at 08:34:48AM -0500, Eric Sandeen wrote:
>>> A bug existed in the XFS reflink code between v5.1 and v5.5 in which
>>> the mapping for a COW IO was not trimmed to the mapping of the COW
>>> extent that was found. This resulted in a too-short copy, and
>>> corruption of other files which shared the original extent.
>>>
>>> (This happened only when extent size hints were set, which bypasses
>>> delalloc and led to this code path.)
>>>
>>> This was (inadvertently) fixed upstream with
>>>
>>> 36adcbace24e "xfs: fill out the srcmap in iomap_begin"
>>>
>>> and related patches which moved lots of this functionality to
>>> the iomap subsystem.
>>>
>>> Hence, this is a -stable only patch, targeted to fix this
>>> corruption vector without other major code changes.
>>>
>>> Fixes: 78f0cc9d55cb ("xfs: don't use delalloc extents for COW on files with extsize hints")
>>> Cc: <stable@vger.kernel.org> # 5.4.x
>>> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
>>> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
>>> Reviewed-by: Christoph Hellwig <hch@lst.de>
>>> ---
>>>
>>> V2: Fix typo in subject, add reviewers
>>>
>>> I've tested this with a targeted reproducer (in next email) as well as
>>> with xfstests.
>>>
>>> There is also now a testcase for xfstests submitted upstream
>>>
>>> Stable folk, not sure how to send a "stable only" patch, or if that's even
>>> valid. Assuming you're willing to accept it, I would still like to have
>>> some formal Reviewed-by's from the xfs developer community before it gets
>>> merged.
>>
>> This is perfect stable-process-wise :) Will wait for reviews/acks before
>> merging.
>
>Thansk Sasha - the reviews/acks were given for V1 (hch & darrick), V2 adds them to the
>commit log (see above) and fixes a typo in the subject.
Ah, I see. Queued up!
--
Thanks,
Sasha
prev parent reply other threads:[~2020-10-02 23:17 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-01 13:34 [PATCH STABLE V2] xfs: trim IO to found COW extent limit Eric Sandeen
2020-10-02 13:07 ` Sasha Levin
2020-10-02 13:19 ` Eric Sandeen
2020-10-02 15:58 ` Darrick J. Wong
2020-10-02 23:17 ` Sasha Levin [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201002231718.GH2415204@sasha-vm \
--to=sashal@kernel.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-xfs@vger.kernel.org \
--cc=sandeen@sandeen.net \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox