2007-09-24 16:57:07

by Antoine Martin

[permalink] [raw]
Subject: bug in fsck or ext2/ext3?

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Hi Ted / LKML,

I've got this snapshot of an ext3 filesystem with a directory that
simply cannot be removed! (image below is just 1.2MB)
As root:
# wget http://users.nagafix.co.uk/~antoine/root-broken.bz2
# bunzip2 root-broken.bz2
# mount -o loop -t ext2 root-broken ./tmp
# rm -fr tmp/chroot.broken
rm: cannot remove directory (...)
Same result when trying to do anything to those files chown/chmod/touch:
"Operation not permitted"

Tested with e2fsprogs v1.39 on 3 systems.
Not sure where else to post this...

Cheers
Antoine
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2007-09-24 17:05:19

by Dave Jones

[permalink] [raw]
Subject: Re: bug in fsck or ext2/ext3?

On Mon, Sep 24, 2007 at 05:56:39PM +0100, Antoine Martin wrote:

> I've got this snapshot of an ext3 filesystem with a directory that
> simply cannot be removed! (image below is just 1.2MB)
> As root:
> # wget http://users.nagafix.co.uk/~antoine/root-broken.bz2
> # bunzip2 root-broken.bz2
> # mount -o loop -t ext2 root-broken ./tmp
> # rm -fr tmp/chroot.broken
> rm: cannot remove directory (...)
> Same result when trying to do anything to those files chown/chmod/touch:
> "Operation not permitted"
>
> Tested with e2fsprogs v1.39 on 3 systems.
> Not sure where else to post this...

Various files in the directories it complains about have their 'i'
bit set. lsattr will show you. chattr -i those files, and the
directory is removable again.

Dave

--
http://www.codemonkey.org.uk

2007-09-24 17:15:07

by Alistair John Strachan

[permalink] [raw]
Subject: Re: bug in fsck or ext2/ext3?

On Monday 24 September 2007 17:56:39 Antoine Martin wrote:
> Hi Ted / LKML,
>
> I've got this snapshot of an ext3 filesystem with a directory that
> simply cannot be removed! (image below is just 1.2MB)
> As root:
> # wget http://users.nagafix.co.uk/~antoine/root-broken.bz2
> # bunzip2 root-broken.bz2
> # mount -o loop -t ext2 root-broken ./tmp
> # rm -fr tmp/chroot.broken
> rm: cannot remove directory (...)
> Same result when trying to do anything to those files chown/chmod/touch:
> "Operation not permitted"
>
> Tested with e2fsprogs v1.39 on 3 systems.
> Not sure where else to post this...

URL is broken. Tried doing a "lsattr" to ensure no xattrs (like +i) are set?

--
Cheers,
Alistair.

137/1 Warrender Park Road, Edinburgh, UK.

2007-09-24 18:16:39

by David Newall

[permalink] [raw]
Subject: Re: bug in fsck or ext2/ext3?

Dave Jones wrote:
> On Mon, Sep 24, 2007 at 05:56:39PM +0100, Antoine Martin wrote:
>
> > # rm -fr tmp/chroot.broken
> > rm: cannot remove directory (...)
> > Same result when trying to do anything to those files chown/chmod/touch:
> > "Operation not permitted"
>
> Various files in the directories it complains about have their 'i'
> bit set. lsattr will show you. chattr -i those files, and the
> directory is removable again.

Additionally, this is a classic symptom of malware. A directory named
"..." is a big hint.

2007-09-24 18:22:15

by Dave Jones

[permalink] [raw]
Subject: Re: bug in fsck or ext2/ext3?

On Tue, Sep 25, 2007 at 03:46:25AM +0930, David Newall wrote:
> Dave Jones wrote:
> > On Mon, Sep 24, 2007 at 05:56:39PM +0100, Antoine Martin wrote:
> >
> > > # rm -fr tmp/chroot.broken
> > > rm: cannot remove directory (...)
> > > Same result when trying to do anything to those files chown/chmod/touch:
> > > "Operation not permitted"
> >
> > Various files in the directories it complains about have their 'i'
> > bit set. lsattr will show you. chattr -i those files, and the
> > directory is removable again.
>
> Additionally, this is a classic symptom of malware. A directory named
> "..." is a big hint.

That was "..." as in "more stuff follows" rather than the actual name
being reported.

Dave

--
http://www.codemonkey.org.uk