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  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:   Fri, 22 Feb 2019 11:00:48 -0800
From:   Omar Sandoval <>
To:     Dave Chinner <>
Cc:     Andreas Dilger <>,
        linux-fsdevel <>,
        Al Viro <>,,
        Linux API <>,
        linux-btrfs <>,,,, Theodore Ts'o <>,
        Jaegeuk Kim <>,
        Steve French <>
Subject: Re: [RFC PATCH 0/6] Allow setting file birth time with utimensat()

On Tue, Feb 19, 2019 at 09:18:20AM +1100, Dave Chinner wrote:
> On Sat, Feb 16, 2019 at 06:57:45PM -0700, Andreas Dilger wrote:
> > While it may be a bit of a stretch to call this "forensic evidence", making
> We do forensic analysis of corrupt filesystems looking for evidence
> of what went wrong, not just looking for evidence of what happened
> on systems that have been broken into.
> > it hard to change from except via total root compromise by a skilled hacker
> > is very useful.
> *nod*.
> > If this were to go in (which I'm not in favour of), then there would need to
> > be a CONFIG and/or runtime knob to turn it off (or better to only turn it on),
> > similar to how FIPS and other security options can only go in one direction.
> The problem here is that "inode birth time" is being conflated with
> "user document creation time". These two things are very different.
> i.e. One is filesystem internal information and is not related to
> when the original copy of the data in the file was created, the
> other is user specified metadata that is related to the file data
> contents and needs to travel with the data, not the filesystem.
> IMO, trying to make one on-disk field hold two different types of
> information defeats one or the other purpose, and nobody knows which
> one the field stores for any given file.
> I'd suggest that "authored date" should be a generic system xattr so
> most filesystems support it, not just those that have a birth time
> field on disk. Sure, modify it through utimesat() and expose it
> through statx() (as authored time, not birth time), but store it a
> system xattr rather than an internal filesystem metadata field that
> requires was never intended to be user modifiable.

It seems that this is the general consensus, so I'll look into
implementing this functionality as an xattr.

Powered by blists - more mailing lists