Rescuing a Damaged USB Stick

[William Park]

On Mon, Dec 19, 2011 at 12:17:04AM -0500, William O'Higgins Witteman wrote:
> I've got an nice clean image of a USB stick on my hard drive.  I'm
> pretty sure there is still data on it - stings returns *oodles* of
> stuff.  The problem is that there is no partition table on this thing -
> gpart says that there are no partitions.
> 
> So, I can't mount the image (or the stick) 'cause there are no
> partitions.  I'm pretty sure it was a FAT32 stick, so I'd love to
> somehow replace the partition table on the image I've got and see if I
> can pull off some of that data.
> 
> Anyone have a set of documents for this?  I've found lots of
> almost-useful information, including some really old docs, but nothing
> that says "do this!" for my situation.
> 
> Thanks!

Odd that it doesn't have partition table.  Windows always creates the
first partition.  Unless it was created from Linux to use the whole
device.  In any case, you can take a peek into the image:

    # losetup usb.img
	-- check /proc/partition to see that "loop0" is created

    # fdisk -u -l /dev/loop0
	-- if you see partitions, say loop0p1, then create loop device
	for that.  Calculate the offset into the first partition, like
	    # losetup usb.img -o $((2048*512))
		-- check /proc/partitions to see "loop1"
	    # mount /dev/loop1 /mnt

	-- if you don't see partition, then it's probably using the
	whole device.  Then, just mount it.
	    # mount /dev/loop0 /mnt

    # losetup -d /dev/loop0
    # losetup -d /dev/loop1
	-- delete the loop devices
-- 
William
--
The Toronto Linux Users Group.      Meetings: http://gtalug.org/
TLUG requests: Linux topics, No HTML, wrap text below 80 columns
How to UNSUBSCRIBE: http://gtalug.org/wiki/Mailing_lists