Re: [dm-crypt] The future of disk encryption with LUKS2

[Arno Wagner <arno@wagner.name>]

On Mon, Feb 08, 2016 at 21:31:05 CET, f-dm-c@media.mit.edu wrote:
>     > Date: Mon, 8 Feb 2016 17:41:43 +0100
>     > From: Arno Wagner <arno@wagner.name>
> 
>     > The thing is that in a typical PC, power drops relatively 
>     > slowly and disks work non-seeking for a lower voltage
>     > that the thresholds. Add to that that a single sector
>     > write takes less than 1ms (probably much less), and
>     > you get ample time to finish a write in progress.
> 
> If the data has already made it all the way into the drive itself,
> that may be valid, but it's very dangerous to make such assumptions
> in general, and you can't necessarily know the timing of the power
> failure vs when the data makes it to the disk, much less the platters.
> 
> http://zork.net/~nick/mail/why-reiserfs-is-teh-sukc
> 
> And new technologies may change this---not just SSDs, but modern
> high-capacity drives that must rewrite many, many sectors to write
> one.  (Yes, I know this also argues that those headers should be
> far away from each other.  So be it.  If such scattered headers
> don't prevent resizing, I don't care.  Except maybe for secure wipe.)

My argument only relates to sectors getting corrupted by
power failure, not other things. For that, the drive must
become unable to write in mid-sector.

Regards,
Arno
-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
----
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