Reset HDD user password, if I know the HDD master password?

Solution 1:

I solved this problem for my own use case. Here is my observation, without any claim of deep knowledge or understanding.

I used hdparm, following the instructions by user StudMuffin on serverfault, how to unlock a ssd disk with hdparm

Commands

The basic commands, on a Linux where the disk is connected:

hdparm --user-master m --security-unlock PASS /dev/sdx
hdparm --user-master m --security-disable PASS /dev/sdx

Before and after and between these steps, one can use hdparm -I /dev/sdx to check the status.

I would suggest to use some kind of trick to not have the password in bash history.

I did this for all drives that were affected: The on-board iSSD, and the 2.5'' SSD.

Result / Observations

My observation confirms the first comment by JeremyS in there: The HDD master password does unlock the disk and make it completely readable again.

The BIOS now reports that no HDD password is active.

Still I stand by my report that the BIOS did NOT allow me to use the master pw to remove the user pw. Only hdparm was able to do this. I assume that technically this would be possible in BIOS, just my BIOS sucks.

I do NOT know if the HDD password actually did enable the hardware disk encryption, or if it only enabled a weak-ish lock.