linux-kernel - Re: [PATCH AUTOSEL 4.20 42/77] dm: fix clone_bio() to trigger blk_recount

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190227173821.GK10616@sasha-vm>
Date:   Wed, 27 Feb 2019 12:38:21 -0500
From:   Sasha Levin <sashal@...nel.org>
To:     Mike Snitzer <snitzer@...hat.com>
Cc:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [PATCH AUTOSEL 4.20 42/77] dm: fix clone_bio() to trigger
 blk_recount_segments()

On Thu, Feb 14, 2019 at 10:49:09PM -0500, Mike Snitzer wrote:
>On Thu, Feb 14 2019 at  9:08pm -0500,
>Sasha Levin <sashal@...nel.org> wrote:
>
>> From: Mike Snitzer <snitzer@...hat.com>
>>
>> [ Upstream commit 57c36519e4b949f89381053f7283f5d605595b42 ]
>>
>> DM's clone_bio() now benefits from using bio_trim() by fixing the fact
>> that clone_bio() wasn't clearing BIO_SEG_VALID like bio_trim() does;
>> which triggers blk_recount_segments() via bio_phys_segments().
>>
>> Reviewed-by: Ming Lei <ming.lei@...hat.com>
>> Signed-off-by: Mike Snitzer <snitzer@...hat.com>
>> Signed-off-by: Sasha Levin <sashal@...nel.org>
>
>Please no, I later effectively reverted this change with commit
>fa8db4948f522 ("dm: don't use bio_trim() afterall")

I've dropped it, thank you.

>(As and aside, I really shouldn't have to defend against stable@ bots
>picking up a commit, like 57c36519e4b949f, that wasn't marked for
>stable@.)

Is it the case that this commit isn't appropriate for stable for some
reason, or was it just buggy?

--
Thanks,
Sasha