linux-ext4 - Re: rfc: [patch] change attribute for ext3

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]

Message-Id: <20060913133136.449c731a.rdunlap@xenotime.net>
Date:	Wed, 13 Sep 2006 13:31:36 -0700
From:	"Randy.Dunlap" <rdunlap@...otime.net>
To:	Trond Myklebust <trond.myklebust@....uio.no>
Cc:	Alexandre Ratchov <alexandre.ratchov@...l.net>,
	linux-ext4@...r.kernel.org, nfsv4@...ux-nfs.org
Subject: Re: rfc: [patch] change attribute for ext3

On Wed, 13 Sep 2006 15:06:02 -0400 Trond Myklebust wrote:

> On Wed, 2006-09-13 at 20:30 +0200, Alexandre Ratchov wrote:
> > On Wed, Sep 13, 2006 at 02:11:11PM -0400, Trond Myklebust wrote:
> > > On Wed, 2006-09-13 at 18:42 +0200, Alexandre Ratchov wrote:
> > > > hello, 
> > > > 
> > > > here is a small patch that adds the "change attribute" for ext3
> > > > file-systems;
> > > > 
> > > > the change attribute is a simple counter that is reset to zero on
> > > > inode creation and that is incremented every time the inode data is
> > > > modified (similarly to the "ctime" time-stamp).
> > > 
> > > I would really have preferred a full-blown 64-bit counter as per
> > > RFC3530, but I suppose we could always combine this change attribute
> > > with the high word from ctime in order to make up the NFSv4 change
> > > attribute. That should keep us safe until someone develops a ramdisk
> > > with < 1 nsecond access time.
> > > 
> > 
> > do you mean something like "(ctime.tv_sec << 32) | change_attribute"? this
> > would allow 2^32 inode changes per second.
> 
> Yes. As I said, that probably ought to suffice for now.
> 
> > For ext3 it's hard to find unused bits in the on-disk inode structure, but
> > ext4 inode may become larger in the future, allowing a 64bit counter.
> 
> In anticipation of that event, could you please change the field in
> 'struct stat' and 'struct stat64' to be an 'unsigned long long' instead
> of the current 'unsigned long'?
> 
> All the other fields are internal to the kernel, so a future change of
> their size should not matter.

and while you are making changes + resubmitting,
Signed-off-by:
needs to have name + email address.

---
~Randy
-
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