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]
Date:	Sun, 16 Feb 2014 19:01:17 -0500
From:	Theodore Ts'o <tytso@....edu>
To:	Vegard Nossum <vegard.nossum@...cle.com>
Cc:	Kalpak Shah <kalpak@...sterfs.com>,
	Andreas Dilger <adilger@...sterfs.com>,
	linux-ext4@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>
Subject: Re: ext4 info leak in creation times in latest mainline

On Sun, Feb 16, 2014 at 04:52:37PM +0100, Vegard Nossum wrote:
> There seems to be a bug in ext4 where the i_crtime of struct
> ext4_inode_info is not initialised, so (some) creation times contain
> essentially random values....
> 
> I don't know if it's relevant, but the filesystem is actually ext3
> mounted using ext4. It's 100% reproducible for me, so I can test
> patches.

Thanks for the bug report.  I see the problem; it was indeed relevant
that this was an ext3 file systmem mounted as ext4.  The first time
when an ext3 inode is read by ext4, i_extra_isize is too small, and so
there is no i_crtime field.  The bug is in EXT4_EINODE_GET_XTIME() (in
ext4.h, where it is leaving ei->i_crtime.tv_sec uninitialized.

It's an easy fix.  I'll send out a patch shortly.

Cheers,

						- Ted
--
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

Powered by blists - more mailing lists