Cinder wipe fails in an insecure manner on Grizzly
---

### Summary ###
A configuration error can prevent the secure erase of volumes in Cinder on
Grizzly, potentially allowing a user to recover another user’s data.

### Affected Services / Software ###
Cinder, Grizzly

### Discussion ###
In Cinder on Grizzly, a configurable method to perform a secure erase of
volumes was added. In the event of a misconfiguration no secure erase will
be performed.

The default code path in Cinder’s clear_volume() method, which is taken
in the event of a configuration error, results in no wiping of the volume -
even in the event that the user had flagged the volume for wiping.

This is the same behaviour as if the volume_clear = ‘none’ option was
selected. This could let an attacker recover data from a volume that was
intended to be securely erased. Examples of possible incorrect
configuration options include values that would appear to result in a
secure erase, for example “volume_clear = true” or “volume_clear =
yes”.

In the event of a misconfiguration resulting in this issue, the message
“Error unrecognized volume_clear option” should be present in log
files.

### Recommended Actions ###
- Create and clear a volume (cinder create --display_name erasetest 10;
cinder delete erasetest)
- Review log files for the above error message (grep “Error unrecognized
volume_clear option” <logfile>)
- Review configuration files to ensure that the valid options ‘zero’ or
‘shred’ are specified.


### Contacts / References ###
This OSSN : https://wiki.openstack.org/wiki/OSSN/OSSN-0016
Original LaunchPad Bug : https://bugs.launchpad.net/cinder/+bug/1322766
OpenStack Security ML : openstack-security@lists.openstack.org
OpenStack Security Group : https://launchpad.net/~openstack-ossg