retype can result in negative values in quota_usages

[Ollie Leahy]

On a devstack installation with two lvm volume types created, retyping from one volume type to another can result in negative vales in the 'reserved' column in the quota_usages table.

To make this happen you need to pass different, probably admin, username and password on the command line.

ubuntu@trusty-devstack:/opt/stack/cinder$ mysql -uroot -ppassword cinder -e "select id,resource,reserved from quota_usages where project_id='f1a9a9b1cff94a37ab879679fa5b4c10';"
+----+-----------------------+----------+
| id | resource | reserved |
+----+-----------------------+----------+
| 1 | gigabytes | 0 |
| 2 | gigabytes_lvmdriver-1 | 0 |
| 3 | volumes_lvmdriver-1 | 0 |
| 4 | volumes | 0 |
| 5 | gigabytes_LUKS | 0 |
| 6 | volumes_LUKS | 0 |
| 7 | gigabytes_lvm2 | 0 |
| 8 | volumes_lvm2 | 0 |
+----+-----------------------+----------+

Retype a volume belonging to 'demo' but using 'admin' creds:

ubuntu@trusty-devstack:~/devstack$ cinder --os-username admin --os-tenant-name admin retype --migration-policy on-demand b60038b1-ca10-4d96-8b02-d82213ba419b lvmdriver-1

Now demo has negative values:

ubuntu@trusty-devstack:/opt/stack/cinder$ mysql -uroot -ppassword cinder -e "select id,resource,reserved from quota_usages where project_id='f1a9a9b1cff94a37ab879679fa5b4c10';"
+----+-----------------------+----------+
| id | resource | reserved |
+----+-----------------------+----------+
| 1 | gigabytes | -1 |
| 2 | gigabytes_lvmdriver-1 | -1 |
| 3 | volumes_lvmdriver-1 | -1 |
| 4 | volumes | -1 |
| 5 | gigabytes_LUKS | 0 |
| 6 | volumes_LUKS | 0 |
| 7 | gigabytes_lvm2 | 0 |
| 8 | volumes_lvm2 | 0 |
+----+-----------------------+----------+

and the admin user is left with an incorrect positive value for the same field:

ubuntu@trusty-devstack:/opt/stack/cinder$ mysql -uroot -ppassword cinder -e "select id,resource,reserved from quota_usages where project_id='57d75a9095ae4ad99722df9115fb2440';"
+----+-----------------------+----------+
| id | resource | reserved |
+----+-----------------------+----------+
| 9 | gigabytes | 1 |
| 10 | gigabytes_lvmdriver-1 | 1 |
| 11 | volumes_lvmdriver-1 | 1 |
| 12 | volumes | 1 |
+----+-----------------------+----------+

The side effect of this bug is that demo can now create one more volume than is specified b their volume quota. Retyping another volume in this way will allow them to create two extra volumes.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/235427

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/235427
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=ceb65b6f868284a6738b5202ea44ac91198d9f1f
Submitter: Jenkins
Branch: master

commit ceb65b6f868284a6738b5202ea44ac91198d9f1f
Author: Ollie Leahy <email address hidden>
Date: Thu Oct 15 15:20:28 2015 +0000

    Use project id from volume when retyping volumes

    Use the project_id from the volume being retyped to reserve quota in
    get_volume_type_reservation(). Previously the project_id from the
    context was used, which could cause reservations to be made and never
    cleared.

    Change-Id: I25f7c00961e259102cdaea6ea9394d04ded96b92
    Closes-Bug: #1505307

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/cinder 8.0.0.0b1 development milestone.