linux-ext4 - Re: [ext3] Changes to block device after an ext3 mount point has been remounted readonly

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]

Date:	Wed, 24 Feb 2010 17:59:41 +0100
From:	Jan Kara <jack@...e.cz>
To:	Camille Moncelier <pix@...life.org>
Cc:	"linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>,
	ext4 development <linux-ext4@...r.kernel.org>,
	Jan Kara <jack@...e.cz>
Subject: Re: [ext3] Changes to block device after an ext3 mount point has
 been remounted readonly

On Wed 24-02-10 17:26:37, Camille Moncelier wrote:
> > Theoretically some pages may exist after rw=>ro remount
> > because of generic race between write/sync, And they will be written
> > in by writepage if page already has buffers. This not happen in ext4
> > because. Each time it try to perform writepages it try to start_journal
> > and this result in EROFS.
> > The race bug will be closed some day but new one may appear again.
> >
> > Let's be honest and change ext3 writepage like follows:
> > - check ROFS flag inside write page
> > - dump writepage's errors.
> >
> >
> I think I don't understand correctly your patch. For me it seems that
> when an ext3 filesystem is remounted ro, some data may not have been
> written to disk right ?
  I think that Dmitry was concerned about the fact that a process could
open a file and write to it after we synced the filesystem in
do_remount_sb().

								Honza
-- 
Jan Kara <jack@...e.cz>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html