block_device_mapping_v2.disk_bus allows invalid values

[Lee Yarwood]

Description
===========

There is no validation of the provided disk_bus in the API, with libvirt this eventually leads to the driver and hypervisor eventually ignoring the requested disk_bus and defaulting to virtio.

Steps to reproduce
==================

A common mistake for users to make is to request a virtio-scsi disk_bus:

$ nova boot --flavor 2 --block-device id=a37d4630-fbc0-4b8e-91a0-18346f907830,source=image,dest=volume,size=1,bus=virtio-scsi,bootindex=0 --nic net-name=private test

Expected result
===============

This should be rejected as this is not a supported disk_bus, instead scsi should be used.

Actual result
=============

The value is ignored and the instance defaults to a virtio bus.

Environment
===========
1. Exact version of OpenStack you are running. See the following
  list for all releases: http://docs.openstack.org/releases/

   master

2. Which hypervisor did you use?
   (For example: Libvirt + KVM, Libvirt + XEN, Hyper-V, PowerKVM, ...)
   What's the version of that?

   Libvirt + KVM

2. Which storage type did you use?
   (For example: Ceph, LVM, GPFS, ...)
   What's the version of that?

   N/A

3. Which networking type did you use?
   (For example: nova-network, Neutron with OpenVSwitch, ...)

   N/A

Logs & Configs
==============

$ nova boot --flavor 2 --block-device id=a37d4630-fbc0-4b8e-91a0-18346f907830,source=image,dest=volume,size=1,bus=virtio-scsi,bootindex=0 --nic net-name=private test
[..]
$ sudo virsh domblklist 45bee4d4-1092-4829-9d98-d32337eb6caf
 Target Source
-----------------------------------------------------------------------------------------------------------------
 vda /opt/stack/data/nova/mnt/896fb15da6036b68a917322e72ebfe57/volume-f866cbb6-b793-4c89-a7e2-b3e0c6f4c2e7

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/724842

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/724842
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=5913bd889f9d3dfc8d154415e666c821054c229d
Submitter: Zuul
Branch: master

commit 5913bd889f9d3dfc8d154415e666c821054c229d
Author: Lee Yarwood <email address hidden>
Date: Fri May 1 14:20:04 2020 +0100

    compute: Validate a BDMs disk_bus when provided

    Previously disk_bus values were never validated and could easily end up
    being ignored by the underlying virt driver and hypervisor.

    For example, a common mistake made by users is to request a virtio-scsi
    disk_bus when using the libvirt virt driver. This however isn't a valid
    bus and is ignored, defaulting back to the virtio (virtio-blk) bus.

    This change adds a simple validation in the compute API using the
    potential disk_bus values provided by the DiskBus field class as used
    when validating the hw_*_bus image properties.

    Closes-Bug: #1876301
    Change-Id: I77b28b9cc8f99b159f628f4655d85ff305a71db8

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/ussuri
Review: https://review.opendev.org/744550

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/train
Review: https://review.opendev.org/744552

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/stein
Review: https://review.opendev.org/744554

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/744550
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=fb31ae430a2e4f8869e77e31ea0d6a9478f6aa61
Submitter: Zuul
Branch: stable/ussuri

commit fb31ae430a2e4f8869e77e31ea0d6a9478f6aa61
Author: Lee Yarwood <email address hidden>
Date: Fri May 1 14:20:04 2020 +0100

    compute: Validate a BDMs disk_bus when provided

    Previously disk_bus values were never validated and could easily end up
    being ignored by the underlying virt driver and hypervisor.

    For example, a common mistake made by users is to request a virtio-scsi
    disk_bus when using the libvirt virt driver. This however isn't a valid
    bus and is ignored, defaulting back to the virtio (virtio-blk) bus.

    This change adds a simple validation in the compute API using the
    potential disk_bus values provided by the DiskBus field class as used
    when validating the hw_*_bus image properties.

    Closes-Bug: #1876301
    Change-Id: I77b28b9cc8f99b159f628f4655d85ff305a71db8
    (cherry picked from commit 5913bd889f9d3dfc8d154415e666c821054c229d)

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/744552
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=bbc562c572f328cc6ffa9cdbff83ae64672fe5b8
Submitter: Zuul
Branch: stable/train

commit bbc562c572f328cc6ffa9cdbff83ae64672fe5b8
Author: Lee Yarwood <email address hidden>
Date: Fri May 1 14:20:04 2020 +0100

    compute: Validate a BDMs disk_bus when provided

    Previously disk_bus values were never validated and could easily end up
    being ignored by the underlying virt driver and hypervisor.

    For example, a common mistake made by users is to request a virtio-scsi
    disk_bus when using the libvirt virt driver. This however isn't a valid
    bus and is ignored, defaulting back to the virtio (virtio-blk) bus.

    This change adds a simple validation in the compute API using the
    potential disk_bus values provided by the DiskBus field class as used
    when validating the hw_*_bus image properties.

    Conflicts:
        nova/tests/unit/compute/test_compute_api.py

    NOTE(lyarwood): Conflict as If9c459a9a0aa752c478949e4240286cbdb146494 is
    not present in stable/train. test_validate_bdm_disk_bus is also updated
    as Ib31ba2cbff0ebb22503172d8801b6e0c3d2aa68a is not present in
    stable/train.

    Closes-Bug: #1876301
    Change-Id: I77b28b9cc8f99b159f628f4655d85ff305a71db8
    (cherry picked from commit 5913bd889f9d3dfc8d154415e666c821054c229d)
    (cherry picked from commit fb31ae430a2e4f8869e77e31ea0d6a9478f6aa61)

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Elod Illes <email address hidden>" on branch: stable/stein
Review: https://review.opendev.org/c/openstack/nova/+/744554
Reason: This branch transitioned to End of Life for this project, open patches needs to be closed to be able to delete the branch.