security issue: hard disk lock

From: Jonas Diemer
Date: Mon Apr 04 2005 - 12:43:45 EST


Hello!

I don't know if you guys already know, there is a possible security risk with
all modern desktop-pcs and ata hard drives. In short:

Modern ata drives can be locked by password. This lock could be set by a
malicous software. This security feature can be frozen, so no programs can
set a lock until the next reboot. Ususally, the BIOS should take care of
locking the security feature, but most desktop BIOSes (unlike laptop BIOSes)
fail to do so. Once a lock is set and the password is unknown, the drive is
trash.

See http://www.heise.de/ct/english/05/08/172/ for more details.

In the above article, a patched hdparm is used to freeze the drive's security
features. This can be used during boot to prevent programs from setting a
password. However, a malicous program could infect the computer and install
itself in the boot sequence prior to the execution of hdparm...

I figured there could be a kernel compiled-in option that will make the kernel
lock all drives found during bootup. then, a malicous program would need to
install a different kernel in order to harm the drive, which would be much
more secure.

What do you think of this?

Regards,
Jonas

PS: Please CC me in replies, I am not subscribed to the list.
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