Disk edits:
- edit_disk built a new <disk> from the form and replaced the old one,
losing what the form does not show (e.g. encryption and virtio
driver options); a bus change detached and re-attached the disk.
The disk of the persistent definition is now edited in place and the
domain defined once; a bus change picks a free device name and drops
the old address and virtio-only options. Pending persistent changes of
a running VM are kept.
- Clone omits empty disk devices, refuses a disk without a supported
source and destination, and checks the name before allocating storage.
Locks:
- Every VM change held its compute's exclusive lock, so one slow
operation blocked all VMs on that compute. A VM change now holds its
own VM lock plus a shared compute lock; reconciliation, migration and
cloning hold the compute exclusively (two clones of different VMs
must not pass the name check together).
- Quota-checked changes of one user (CPU, memory and disk resize,
clone) run one at a time under a per-user lock, also across computes,
so concurrent requests cannot all pass the check against the old
allocation. It is the outermost lock; superusers, who have no quota,
skip it.
- A busy lock answers 409 to the API and a message in the web UI. API
power and destroy actions return the view's error instead of success.
Clone refused VMs that cloned fine before: a disk without a volume got a
None disk name, and a source image with characters such as a space or "@"
produced a derived name outside the allowed pattern. Disks without a
volume (which clone_instance does not copy) are no longer validated, and
derived disk names are sanitized to the allowed charset. Names typed by a
superuser are still validated strictly.
clone only required "view" access, so a user with clone_instances and the
global view_instances permission could clone anyone's VM and read its
disks. It also copied every POST field into clone_data, which let the
client override the server-set disk_owner_uid/gid, and disk-<dev> values
went unvalidated into volume XML and os.path.join.
- Require change permission on the source VM, except for templates,
which any user who can view them may clone.
- Build clone_data from an allowlist: name, title and description for
everyone; disk names and MAC addresses only from superusers.
- For non-superusers, derive disk names (get_clone_disk_name) and MAC
addresses (DHCP or random) on the server; their form only sent the
source VM's own values, which could never work.
- Validate every MAC address (not only the first) and every disk name;
a missing MAC is an error message instead of a KeyError.
