[Bug 33451] pumount deletes partition entries under /dev

[robepisc]

Public bug reported:
https://launchpad.net/malone/bugs/33451

Affects: linux-source-2.6.15 (Ubuntu)
       Severity: Normal
       Priority: (none set)
       Assignee: Ben Collins
         Status: Confirmed

Description:
When you pumount a partition (let's say sda1) previously mounted by
pmount,  /dev/sda1 disappears, even if the device is still plugged in.

To reproduce:
1. Plug in a usb-key
2. wait until it's automatically mounted by g-v-m
3. verify that /dev/sda and /dev/sda1 appeared
4. pumount /dev/sda1 (or do the same from Nautilus)
5. /dev/sda is still there (good), /dev/sda1 is no more (bad!!)

There's no way to remount that partition (since it doesn't have an entry
in /dev/ anymore), unless I unplug the usb-disk and plug it in again.

Note that, because of this bug, you can't use any command which acts on
unmounted partitions (for example fsck) on removable disks, since they
get mounted automatically and, once unmounted, disappear.

I found this on pmount 0.9.7-2ubuntu2 (from Dapper Flight 4).