https://bugzilla.redhat.com/show_bug.cgi?id=1038363

If a domain has a different maximum for persistent and live maxmem
or max vcpus, then it is possible to hit cases where libvirt
refuses to adjust the current values or gets halfway through
the adjustment before failing.  Better is to determine up front
if the change is possible for all requested flags.

Based on an idea by Geoff Franks.

* src/qemu/qemu_driver.c (qemuDomainSetMemoryFlags): Compute
correct maximum if both live and config are being set.
(qemuDomainSetVcpusFlags): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

To reuse this from other drivers, like lxc.

Add support for gluster backed images as sources for snapshots in the
qemu driver. This will also simplify adding further network backed
volumes as sources for snapshot in case qemu will support them.

Use the new storage driver based "stat" api to detect exiting files just
as we did with local files.

Use the new storage driver APIs to delete snapshot backing files in case
of failure instead of directly relying on "unlink". This will help us in
the future when we will be adding network based storage without local
representation in the host.

All the data for getting the actual type is present in the snapshot
config. There is no need to have this function private to the qemu
driver and it will be re-used later in other parts of libvirt

All the data for getting the actual type is present in the domain
config. There is no need to have this function private to the qemu
driver and it will be re-used later in other parts of libvirt

On some platforms like IBM PowerNV the NUMA node numbers can be
non-sequential. For eg. numactl --hardware o/p from such a machine looks
as given below

node distances:
   node   0   1  16  17
     0:  10  40  40  40
     1:  40  10  40  40
    16:  40  40  10  40
    17:  40  40  40  10

The NUMA nodes are 0,1,16,17

Libvirt uses sequential index as NUMA node numbers and this can
result in crash or incorrect results.
Signed-off-by: NShivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: NPradipta Kr. Banerjee <bpradip@in.ibm.com>

The code took into account only the global permissions. The domains now
support per-vm DAC labels and per-image DAC labels. Use the most
specific label available.

This commit allows to attach/detach a <filesystem> device in qemu. For
this purpose I'm introducing two new functions: virDomainFSInsert() and
virDomainFSRemove() and adding necessary code in the qemu driver.  It
compares filesystems based on their "destination" folder. So if two
filesystems share the same destination, they are considered equal and
the qemu driver would reject the insertion.
Signed-off-by: NMatthieu Coudron <mattator@gmail.com>

When attempting a blockcommit from the top layer, the base argument
passed is NULL. This will be dereferenced when attempting a commit with
an empty image chain. Output the real volume path instead:

virsh blockcommit --verbose --path vda --domain DOMNAME --wait
error: invalid argument: top '/path/somefile' in chain for 'vda' has no backing file

instead of:

error: invalid argument: top '(null)' in chain for 'vda' has no backing file

https://bugzilla.redhat.com/show_bug.cgi?id=1058839

Commit f9f56340 for CVE-2014-0028 almost had the right idea - we
need to check the ACL rules to filter which events to send.  But
it overlooked one thing: the event dispatch queue is running in
the main loop thread, and therefore does not normally have a
current virIdentityPtr.  But filter checks can be based on current
identity, so when libvirtd.conf contains access_drivers=["polkit"],
we ended up rejecting access for EVERY event due to failure to
look up the current identity, even if it should have been allowed.

Furthermore, even for events that are triggered by API calls, it
is important to remember that the point of events is that they can
be copied across multiple connections, which may have separate
identities and permissions.  So even if events were dispatched
from a context where we have an identity, we must change to the
correct identity of the connection that will be receiving the
event, rather than basing a decision on the context that triggered
the event, when deciding whether to filter an event to a
particular connection.

If there were an easy way to get from virConnectPtr to the
appropriate virIdentityPtr, then object_event.c could adjust the
identity prior to checking whether to dispatch an event.  But
setting up that back-reference is a bit invasive.  Instead, it
is easier to delay the filtering check until lower down the
stack, at the point where we have direct access to the RPC
client object that owns an identity.  As such, this patch ends
up reverting a large portion of the framework of commit f9f56340.
We also have to teach 'make check' to special-case the fact that
the event registration filtering is done at the point of dispatch,
rather than the point of registration.  Note that even though we
don't actually use virConnectDomainEventRegisterCheckACL (because
the RegisterAny variant is sufficient), we still generate the
function for the purposes of documenting that the filtering
takes place.

Also note that I did not entirely delete the notion of a filter
from object_event.c; I still plan on using that for my upcoming
patch series for qemu monitor events in libvirt-qemu.so.  In
other words, while this patch changes ACL filtering to live in
remote.c and therefore we have no current client of the filtering
in object_event.c, the notion of filtering in object_event.c is
still useful down the road.

* src/check-aclrules.pl: Exempt event registration from having to
pass checkACL filter down call stack.
* daemon/remote.c (remoteRelayDomainEventCheckACL)
(remoteRelayNetworkEventCheckACL): New functions.
(remoteRelay*Event*): Use new functions.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Drop unused parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/domain_event.c (virDomainEventFilter): Delete unused
function.
* src/conf/network_event.c (virNetworkEventFilter): Likewise.
* src/libxl/libxl_driver.c: Adjust caller.
* src/lxc/lxc_driver.c: Likewise.
* src/network/bridge_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/test/test_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/vbox/vbox_tmpl.c: Likewise.
* src/xen/xen_driver.c: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

The NWFilter code has as a deadlock race condition between
the virNWFilter{Define,Undefine} APIs and starting of guest
VMs due to mis-matched lock ordering.

In the virNWFilter{Define,Undefine} codepaths the lock ordering
is

  1. nwfilter driver lock
  2. virt driver lock
  3. nwfilter update lock
  4. domain object lock

In the VM guest startup paths the lock ordering is

  1. virt driver lock
  2. domain object lock
  3. nwfilter update lock

As can be seen the domain object and nwfilter update locks are
not acquired in a consistent order.

The fix used is to push the nwfilter update lock upto the top
level resulting in a lock ordering for virNWFilter{Define,Undefine}
of

  1. nwfilter driver lock
  2. nwfilter update lock
  3. virt driver lock
  4. domain object lock

and VM start using

  1. nwfilter update lock
  2. virt driver lock
  3. domain object lock

This has the effect of serializing VM startup once again, even if
no nwfilters are applied to the guest. There is also the possibility
of deadlock due to a call graph loop via virNWFilterInstantiate
and virNWFilterInstantiateFilterLate.

These two problems mean the lock must be turned into a read/write
lock instead of a plain mutex at the same time. The lock is used to
serialize changes to the "driver->nwfilters" hash, so the write lock
only needs to be held by the define/undefine methods. All other
methods can rely on a read lock which allows good concurrency.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add support for specifying various types when doing snapshots. This will
later allow to do snapshots on network backed volumes. Disks of type
'volume' are not supported by snapshots (yet).

Also amend the test suite to check parsing of the various new disk
types that can now be specified.

Currently the qemuDomainGetBlockInfo will return allocation == physical
for most backing stores. For a qcow2 block backed device it's possible
to return the highest lv extent allocated from qemu for an active guest.
That is a value where allocation != physical and one would hope be less.
However, if the guest is not running, then the code falls back to returning
allocation == physical. This turns out to be problematic for rhev which
monitors the size of the backing store. During a migration, before the
VM has been started on the target and while it is deemed inactive on the
source, there's a small window of time where the allocation is returned
as physical triggering the code to extend the file unnecessarily.

Since rhev uses transient domains and this is edge condition for a transient
domain, rather than returning good status and allocation == physical when
this "window of opportunity" exists, this patch will check for a transient
(or non persistent) domain and return a failure to the caller rather than
returning the defaults. For a persistent domain, the defaults will be
returned. The description for the virDomainGetBlockInfo has been updated
to describe the phenomena.

the array params is allocated by VIR_ALLOC_N in
remoteDispatchDomainGetCPUStats. it had been set
to zero. No need to reset it to zero again, and
this reset here is incorrect too, nparams * ncpus
is the array length not the size of params array.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>

I noticed that we allow virDomainGetVcpusFlags even for read-only
connections, but that with a flag, it can require guest agent
interaction.  It is feasible that a malicious guest could
intentionally abuse the replies it sends over the guest agent
connection to possibly trigger a bug in libvirt's JSON parser,
or withhold an answer so as to prevent the use of the agent
in a later command such as a shutdown request.  Although we
don't know of any such exploits now (and therefore don't mind
posting this patch publicly without trying to get a CVE assigned),
it is better to err on the side of caution and explicitly require
full access to any domain where the API requires guest interaction
to operate correctly.

I audited all commands that are marked as conditionally using a
guest agent.  Note that at least virDomainFSTrim is documented
as needing a guest agent, but that such use is unconditional
depending on the hypervisor (so the existing domain:fs_trim ACL
should be sufficient there, rather than also requirng domain:write).
But when designing future APIs, such as the plans for obtaining
a domain's IP addresses, we should copy the approach of this patch
in making interaction with the guest be specified via a flag, and
use that flag to also require stricter access checks.

* src/libvirt.c (virDomainGetVcpusFlags): Forbid guest interaction
on read-only connection.
(virDomainShutdownFlags, virDomainReboot): Improve docs on agent
interaction.
* src/remote/remote_protocol.x
(REMOTE_PROC_DOMAIN_SNAPSHOT_CREATE_XML)
(REMOTE_PROC_DOMAIN_SET_VCPUS_FLAGS)
(REMOTE_PROC_DOMAIN_GET_VCPUS_FLAGS, REMOTE_PROC_DOMAIN_REBOOT)
(REMOTE_PROC_DOMAIN_SHUTDOWN_FLAGS): Require domain:write for any
conditional use of a guest agent.
* src/xen/xen_driver.c: Fix clients.
* src/libxl/libxl_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/lxc/lxc_driver.c: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1034993

SCSI passthrough disks (<disk .. device="lun">) can't be used as backing
for snapshots. Currently with upstream qemu the vm crashes on such
attempt.

This patch adds a early check to catch an attempt to do such a snapshot
and rejects it right away. qemu will fix the issue but this will let us
control the error message.

We shouldn't access the domain definition while we are in the monitor
section as the domain is unlocked. Additionally after we exit from the
monitor we need to check if the VM is still alive. Not doing so resulted
in a crash if qemu exits while attempting to do an external VM snapshot.

https://bugzilla.redhat.com/show_bug.cgi?id=1046919

If none (KVM, VFIO) of the supported PCI passthrough methods is known to
work on a host, it's better to fail right away with a nice error message
rather than letting attachment fail with a more cryptic message such as

    Failed to bind PCI device '0000:07:05.0' to vfio-pci: No such device
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

With this patch, user can setup throttle blkio cgroup
through virsh for qemu domain.
Signed-off-by: NGuan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>

The public virConnectRef and virConnectClose API are just thin
wrappers around virObjectRef/virObjectRef, with added object
validation and an error reset.  Within our backend drivers, use
of the object validation is just an inefficiency since we always
pass valid objects.  More important to think about is what
happens with the error reset; our uses of virConnectRef happened
to be safe (since we hadn't encountered any earlier errors), but
in several cases the use of virConnectClose could lose a real
error.

Ideally, we should also avoid calling virConnectOpen() from
within backend drivers - but that is a known situation that
needs much more design work.

* src/qemu/qemu_process.c (qemuProcessReconnectHelper)
(qemuProcessReconnect): Avoid nested public API call.
* src/qemu/qemu_driver.c (qemuAutostartDomains)
(qemuStateInitialize, qemuStateStop): Likewise.
* src/qemu/qemu_migration.c (doPeer2PeerMigrate): Likewise.
* src/storage/storage_driver.c (storageDriverAutostart):
Likewise.
* src/uml/uml_driver.c (umlAutostartConfigs): Likewise.
* src/lxc/lxc_process.c (virLXCProcessAutostartAll): Likewise.
(virLXCProcessReboot): Likewise, and avoid leaking conn on error.
Signed-off-by: NEric Blake <eblake@redhat.com>

Ever since ACL filtering was added in commit 76397360 (v1.1.1), a
user could still use event registration to obtain access to a
domain that they could not normally access via virDomainLookup*
or virConnectListAllDomains and friends.  We already have the
framework in the RPC generator for creating the filter, and
previous cleanup patches got us to the point that we can now
wire the filter through the entire object event stack.

Furthermore, whether or not domain:getattr is honored, use of
global events is a form of obtaining a list of networks, which
is covered by connect:search_domains added in a93cd08f (v1.1.0).
Ideally, we'd have a way to enforce connect:search_domains when
doing global registrations while omitting that check on a
per-domain registration.  But this patch just unconditionally
requires connect:search_domains, even when no list could be
obtained, based on the following observations:
1. Administrators are unlikely to grant domain:getattr for one
or all domains while still denying connect:search_domains - a
user that is able to manage domains will want to be able to
manage them efficiently, but efficient management includes being
able to list the domains they can access.  The idea of denying
connect:search_domains while still granting access to individual
domains is therefore not adding any real security, but just
serves as a layer of obscurity to annoy the end user.
2. In the current implementation, domain events are filtered
on the client; the server has no idea if a domain filter was
requested, and must therefore assume that all domain event
requests are global.  Even if we fix the RPC protocol to
allow for server-side filtering for newer client/server combos,
making the connect:serach_domains ACL check conditional on
whether the domain argument was NULL won't benefit older clients.
Therefore, we choose to document that connect:search_domains
is a pre-requisite to any domain event management.

Network events need the same treatment, with the obvious
change of using connect:search_networks and network:getattr.

* src/access/viraccessperm.h
(VIR_ACCESS_PERM_CONNECT_SEARCH_DOMAINS)
(VIR_ACCESS_PERM_CONNECT_SEARCH_NETWORKS): Document additional
effect of the permission.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Add new parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/object_event_private.h (virObjectEventStateRegisterID):
Likewise.
* src/conf/object_event.c (_virObjectEventCallback): Track a filter.
(virObjectEventDispatchMatchCallback): Use filter.
(virObjectEventCallbackListAddID): Register filter.
* src/conf/domain_event.c (virDomainEventFilter): New function.
(virDomainEventStateRegister, virDomainEventStateRegisterID):
Adjust callers.
* src/conf/network_event.c (virNetworkEventFilter): New function.
(virNetworkEventStateRegisterID): Adjust caller.
* src/remote/remote_protocol.x
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_REGISTER)
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_REGISTER_ANY)
(REMOTE_PROC_CONNECT_NETWORK_EVENT_REGISTER_ANY): Generate a
filter, and require connect:search_domains instead of weaker
connect:read.
* src/test/test_driver.c (testConnectDomainEventRegister)
(testConnectDomainEventRegisterAny)
(testConnectNetworkEventRegisterAny): Update callers.
* src/remote/remote_driver.c (remoteConnectDomainEventRegister)
(remoteConnectDomainEventRegisterAny): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectDomainEventRegister)
(xenUnifiedConnectDomainEventRegisterAny): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainGetXMLDesc): Likewise.
* src/libxl/libxl_driver.c (libxlConnectDomainEventRegister)
(libxlConnectDomainEventRegisterAny): Likewise.
* src/qemu/qemu_driver.c (qemuConnectDomainEventRegister)
(qemuConnectDomainEventRegisterAny): Likewise.
* src/uml/uml_driver.c (umlConnectDomainEventRegister)
(umlConnectDomainEventRegisterAny): Likewise.
* src/network/bridge_driver.c
(networkConnectNetworkEventRegisterAny): Likewise.
* src/lxc/lxc_driver.c (lxcConnectDomainEventRegister)
(lxcConnectDomainEventRegisterAny): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

CVE-2013-6458

Every API that is going to begin a job should do that before fetching
data from vm->def.

Every API that is going to begin a job should do that before fetching
data from vm->def.

CVE-2013-6458

Every API that is going to begin a job should do that before fetching
data from vm->def.

CVE-2013-6458

Generally, every API that is going to begin a job should do that before
fetching data from vm->def. However, qemuDomainGetBlockInfo does not
know whether it will have to start a job or not before checking vm->def.
To avoid using disk alias that might have been freed while we were
waiting for a job, we use its copy. In case the disk was removed in the
meantime, we will fail with "cannot find statistics for device '...'"
error message.

CVE-2013-6458
https://bugzilla.redhat.com/show_bug.cgi?id=1043069

When virDomainDetachDeviceFlags is called concurrently to
virDomainBlockStats: libvirtd may crash because qemuDomainBlockStats
finds a disk in vm->def before getting a job on a domain and uses the
disk pointer after getting the job. However, the domain in unlocked
while waiting on a job condition and thus data behind the disk pointer
may disappear. This happens when thread 1 runs
virDomainDetachDeviceFlags and enters monitor to actually remove the
disk. Then another thread starts running virDomainBlockStats, finds the
disk in vm->def, and while it's waiting on the job condition (owned by
the first thread), the first thread finishes the disk removal. When the
second thread gets the job, the memory pointed to be the disk pointer is
already gone.

That said, every API that is going to begin a job should do that before
fetching data from vm->def.

Introduced in commit 81fae6b9.

* src/qemu/qemu_driver.c (qemuDomainSetNumaParamsLive): Fix typos.
Signed-off-by: NEric Blake <eblake@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1047234

Add a range check for supported numa memory placement modes provided by
the user before setting them in the domain definition. Without the check
the user is able to provide a (yet) unknown mode which is then stored in
the domain definition. This potentially causes a NULL dereference when
the defintion is formatted into the XML.

To reproduce run:
 virsh numatune DOMNAME --mode 6 --nodeset 0

The XML will then contain:
  <numatune>
      <memory mode='(null)' nodeset='0'/>
  </numatune>

With this fix, the command fails:
 error: Unable to change numa parameters
 error: invalid argument: unsupported numa_mode: '6'

Add whitespace to separate logical code blocks, reformat error messages
and clean up code flow.

This patch changes error handling in some cases where the the loop would
be continued to jump to cleanup instead and error out rather than modify
the domain any further.

The throttle blkio cgroup will reuse this struct.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>

Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>

The virDomainEvent class is kept as it indicates what meta informations
are valid for the children classes. This may be useful in the future.

This aims at providing some consistency with other domain events

Added a parent class virObjectEvent for future event types

Leave virDomainEventRegister and its Deregister brother as these are
legacy functions only for domain lifecycle events.

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

For dead domains that have no memtune limits, we return 0 instead of
"unlimited", this patch fixes it to return PARAM_UNLIMITED.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1035108

When attempting to enable more vCPUs in the guest than is currently
enabled in the guest but less than the maximum count for the VM we
currently reported an unhelpful message:

 error: internal error: guest agent reports less cpu than requested

This patch changes it to:

 error: invalid argument: requested vcpu count is greater than the count
 of enabled vcpus in the domain: 3 > 2