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How not to securely erase a NVME drive (2022) (peterbabic.dev)
58 points by transpute 5 days ago | hide | past | favorite | 54 comments




And this is why you always encrypt the drive with software. All of these methods seem to put a lot of faith into the drive controller doing what it claim it does, which you can never be all that sure about. Even Microsoft-backed Bitlocker would help here.

Bitlocker can rely on the SSD encryption, so careful there too.

It has been software encryption for a many years now.

By default, yes. But it is possible to enable Bitlocker to use a SED directly.

Indeed, LUKS + F2FS for /home with an external key file imported into initrd solves a lot of issues.

Primarily, when an SSD slowly fails the sector replacement allotment has already bled data into read-only areas of the drive. As a user, there is no way to reliably scrub that data.

If the drive suddenly bricks, the warranty service will often not return the original hardware... and just the password protection on an embedded LUKS key is not great.

There are effective disposal methods:

1. shred the chips

2. incinerate the chips

Wiping/Trim sometimes doesn't even work if the Flash chips are malfunctioning. =3


What's wrong with the LUKS password protection?

There is nothing "wrong" with passwords, but they have trade-offs like most approaches. The actual LUKS key is usually wrapped in a password protected record(s) commonly on the storage media by default. That method is usually weaker than the key itself.

Note 10000 GPUs can brute force passwords rather quickly (a pre-sharded search space is fast), and key exfiltration for targeted individuals/firms still happens.

Options like modern TPM include anti-brute force features, but has other attack surfaces. Everyone has their own risk profile, and it is safer to assume if people want in... they will get in sooner or later. ymmv =3


> an external key file imported into initrd

This is exceptionally poor advice. This is why TPM exists. Unfortunately adoption is low with the Linux crowd because they still believe the misinformation from 20 years ago.


I've lost faith that Linux distros will ever fix the problem where some PCR changes and the TPM refuses to unseal the key... the user is left with a recovery passphrase prompt & no way to verify whether they have been attacked by the 'evil maid', or whether it was just because of a kernel or kernel command line or initrd or initrd module change, etc.