Bug Report: openmediavault-luksencryption unsafe usage of devices instead of partitions (potential data loss)

When openmediavault-luksencryption is applied to a device like /dev/md0, it uses the whole device instead of a partition that covers the whole device.

I was so unlucky as to have the automatic partition scanning of Linux to think that there existed two partitions /dev/md0p1 and /dev/md0p2 on my device with 1.5 TByte and 750 GByte each. I think this was because of a random combination of data in the LUKS header or in the content itself. When I tested via parted, there was no valid label on the device.

This led to many problems:

1. In the GUI RAID overview, those devices were shown. After I verified that they devices were unneeded, I tried to remove them in the GUI, thereby removing /dev/md0 as well. Probably the mere existence of these devices would have destroyed the drive content anyway as the recovery of those devices had not begun yet.

2. Upon a reboot, when the RAID5 buildup was not finished yet, the rebuild did not continue, saying "resync=PENDING".

Since I think that one cannot disable probing for partitions, the proper way of handling this would be to create a GPT disk label and a large partition covering the whole device and put the LUKS containers into that partition. When I tried this manually, I could not choose the partition for encryption via the GUI.

You cannot rely on "random data" on a device not to trigger this behaviour.

It may be "expected" behaviour, however, it is risky at best because the interpretation of what is on the block device makes system components believe that there are partitions which are really not there - leading to catastrophic data loss in suite.

I would not (and have never) do that this way. LUKS containers belong in a partition, not on a raw device.

I admit that the probability may be low - but my example shows it is > 0.

Also, I already stated why creating this via CLI is not a workaround.

I filed a bug at Github.

No. I wiped the arrays - besides: if OMV uses only whole devices anyway, why is there no function to do that properly?

The "partitions" were auto-detected after I created multiple LUKS passwords and rebooted the machine. Obviously the "random" key material was being misinterpreted as partition info.

It is dangerous to use the device as a LUKS header can obviously be misinterpreted as partition info. Therefore, a protecting GPT label is needed.