From: Theodore Ts'o Subject: Re: [PATCH] ext4: avoid modifying checksum fields directly during checksum verification Date: Sun, 3 Jul 2016 18:05:13 -0400 Message-ID: <20160703220513.GB17739@thunk.org> References: <1465971173-5612-1-git-send-email-daeho.jeong@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: darrick.wong@oracle.com, linux-ext4@vger.kernel.org, Youngjin Gil To: Daeho Jeong Return-path: Received: from imap.thunk.org ([74.207.234.97]:59798 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932160AbcGCWFT (ORCPT ); Sun, 3 Jul 2016 18:05:19 -0400 Content-Disposition: inline In-Reply-To: <1465971173-5612-1-git-send-email-daeho.jeong@samsung.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, Jun 15, 2016 at 03:12:53PM +0900, Daeho Jeong wrote: > We temporally change checksum fields in buffers of some types of > metadata into '0' for verifying the checksum values. By doing this > without locking the buffer, some metadata's checksums, which are > being committed or written back to the storage, could be damaged. > In our test, several metadata blocks were found with damaged metadata > checksum value during recovery process. When we only verify the > checksum value, we have to avoid modifying checksum fields directly. > > Signed-off-by: Daeho Jeong > Signed-off-by: Youngjin Gil Applied, thanks! - Ted