Protected partitions?

dk_zero-cool · 06-09-2011, 05:04 AM

I have an 4 GB USB Drive that bugs me. When I insert it, the fallowing device maps are created in /dev.

1: sdb
2: sdb1
3: sr0

The sr0 is registered as an Optical Disk that I can't remove for some reason. I have tried providing sdb with an new empty partition table, but the sr0 partition does not get removed by this.

I think it's something created by some Live Linux CD I may have put on the disk at some point. The label is named "U3 System" and it contains the files "LaunchPad.zip" and "LaunchU3.exe".

Does anyone have any idea what this is and how to remove it?

Reuti · 06-09-2011, 05:08 AM

There is a tool at the SanDisk website to remove it - well, at least for OS X and Windows.

dk_zero-cool · 06-09-2011, 05:17 AM

I don't own windows or OS X. Besides, I don't see why any special tool would be needed in Linux since I should have complete access to the disk as Linux is not a limited/locked system.

syg00 · 06-09-2011, 05:25 AM

Guess again. Somebody has to;
a) have access to the proprietary code, and
b) be prepared to write something to fix it.

Needs time and ability (at least).

Reuti · 06-09-2011, 05:30 AM

An USB stick is not like a disk, where you can access just the media by address. Instead therein is a microcontroller which handles the communication between USB and the flash storage. When the microcontroller is supplying the partitions all the time, the program in the microcontroller needs to be changed to present a different device to the host.

This microcontroller is also responsible for a static or dynamic relocation of blocks of memory inside the flash storage to get the most out of its lifetime. There was a report some time ago, that even deleted and overridden information in flash memory might still appear at other locations due to the relocation.

dk_zero-cool · 06-09-2011, 05:50 AM

#5 Thanks for the explanation, did not know that.

But after someone mentioned Scandisk, I did some more searches and found that
writing to /sys/block/sr0/device/delete or /sys/block/scd0/device/delete should remove the partition. (Have not tried yet). Also there is a tool called u3-tool (It's even in some distro's repo's) that is used to work with the U3 partition, even removing it.