linux-ext4 - Re: fsck infinite loop on corrupt ext4 file system

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] [day] [month] [year] [list]

Message-id: <20090818190301.GL5931@webber.adilger.int>
Date:	Tue, 18 Aug 2009 13:03:01 -0600
From:	Andreas Dilger <adilger@....com>
To:	Theodore Tso <tytso@....edu>
Cc:	Frank Mayhar <fmayhar@...gle.com>, linux-ext4@...r.kernel.org
Subject: Re: fsck infinite loop on corrupt ext4 file system

On Aug 18, 2009  13:03 -0400, Theodore Ts'o wrote:
> Something we *could* do to further reduce the chances would be to
> compare the primary and backup group descriptors, either at
> mount-time, or in e2fsck.  This would add an extra level of paranoia,
> although the people who are trying to do 5 second boots with HDD's
> would probably complain about the extra seeks that we'd be introducing
> as a result.

I've thought about this recently as well.  Since the GDT blocks are
allocated contiguously (at least until we get META_BG filesystems) it
would only be a single extra seek and read at mount time.  For a 16TB
filesystem there are 8MB of GDT blocks, so that isn't a huge amount of
extra IO as log as we do it with a single read instead of many seeks.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.

--
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