[cryptography] Deleting data on a flash?

Eugen Leitl eugen at leitl.org
Mon Sep 23 04:24:06 EDT 2013

On Mon, Sep 23, 2013 at 11:02:45AM +0300, ianG wrote:
> On 23/09/13 07:12 AM, Dev Random wrote:
> >I've been thinking about this for a while now and I don't see a way to
> >do this with today's mobile devices without some external help.
> >
> >The issue is that it's pretty much impossible to delete data securely
> >from a flash device.
> Why is that?

I presume it's due to extra blocks due to overprovisioning.
There is no way to verify the block you've zeroed or
randomized has been really overwritten.

It is much easier to destroy the secret of a cryptofs.
I've just looked, and there seems to be no easy way
to mount an encrypted partition on Android, though
GuardianProject has a LUKS howto.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: Digital signature
URL: <http://lists.randombit.net/pipermail/cryptography/attachments/20130923/9f9262c2/attachment.asc>

More information about the cryptography mailing list