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: Eric 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: Jiri Denemark <jdenemar@redhat.com>
With this patch, user can setup throttle blkio cgroup
through virsh for qemu domain.
Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao 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: Eric Blake <eblake@redhat.com>
Ever since ACL filtering was added in commit 7639736 (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 a93cd08 (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: Eric Blake <eblake@redhat.com>
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.
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.
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: Martin 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
Ever since the subcpusets(vcpu,emulator) were introduced, the parent
cpuset cannot be modified to remove the nodes that are in use by the
subcpusets.
The fix is to break the memory node modification into three steps:
1. assign new nodes into the parent,
2. change the nodes in the child nodes,
3. remove the old nodes on the parent node.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1009880
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
This patch resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=1035188
Commit f094aaac48 changed the PCI device assignment in qemu domains
to default to using VFIO rather than legacy KVM device assignment
(when VFIO is available). It didn't change which driver was used by
default for virNodeDeviceDetachFlags(), though, so that API (and the
virsh nodedev-detach command) was still binding to the pci-stub
driver, used by legacy KVM assignment, by default.
This patch publicizes (only within the qemu module, though, so no
additions to the symbol exports are needed) the functions that check
for presence of KVM and VFIO device assignment, then uses those
functions to decide what to do when no driver is specified for
virNodeDeviceDetachFlags(); if the vfio driver is loaded, the device
will be bound to vfio-pci, or if legacy KVM assignment is supported on
this system, the device will be bound to pci-stub; if neither method
is available, the detach will fail.
Currently the snapshot code did not check if it actually supports
snapshots on various disk backends for domains. To avoid future problems
add checkers that whitelist the supported configurations.
When doing an internal snapshot on a VM with sheepdog or RBD disks we
would not set a flag to mark the domain is using internal snapshots and
might end up creating a mixed snapshot. Move the setting of the variable
to avoid this problem.
The virsh command 'domxml-to-native' (virConnectDomainXMLToNative())
converts all network devices to "type='ethernet'" in order to make it
more likely that the generated command could be run directly from a
shell (other libvirt network device types end up referencing file
descriptors for tap devices assumed to have been created by libvirt,
which can't be done in this case).
During this conversion, all of the netdev parameters are cleared out,
then specific items are filled in after changing the type. The MAC
address was not one of these preserved items, and the result was that
mac addresses in the generated commandlines were always
00:00:00:00:00:00.
This patch saves the mac address before the conversion, then
repopulates it afterwards, so the proper mac addresses show up in the
commandline.
Signed-off-by: Bing Bu Cao <mars@linux.vnet.ibm.com>
Signed-off-by: Laine Stump <laine@laine.org>
For attach/detach of controller devices, we rename the functions to
remove 'PCI' from their title. The actual separation of PCI-specific
operations will be handled in the next patch.
Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Most of our code base uses space after comma but not before;
fix the remaining uses before adding a syntax check.
* src/qemu/qemu_cgroup.c: Consistently use commas.
* src/qemu/qemu_command.c: Likewise.
* src/qemu/qemu_conf.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/qemu/qemu_monitor.c: Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
If the managedsave image is corrupted, e.g. the XML part is, we fail to
parse it and throw an error, e.g.:
error: Failed to start domain jms8
error: XML error: missing security model when using multiple labels
This is okay, as we can't really start the machine and avoid undefined
qemu behaviour. On the other hand, the error message doesn't give a
clue to users what should they do. The consensus here would be to thrown
a warning to logs saying "Hey, you've got a corrupted file".
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The following sequence
1. Define a persistent QMEU guest
2. Start the QEMU guest
3. Stop libvirtd
4. Kill the QEMU process
5. Start libvirtd
6. List persistent guests
At the last step, the previously running persistent guest
will be missing. This is because of a race condition in the
QEMU driver startup code. It does
1. Load all VM state files
2. Spawn thread to reconnect to each VM
3. Load all VM config files
Only at the end of step 3, does the 'virDomainObjPtr' get
marked as "persistent". There is therefore a window where
the thread reconnecting to the VM will remove the persistent
VM from the list.
The easy fix is to simply switch the order of steps 2 & 3.
In addition to this though, we must only attempt to reconnect
to a VM which had a non-zero PID loaded from its state file.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Most of the usage of getuid()/getgid() is in cases where we are
considering what privileges we have. As such the code should be
using the effective IDs, not real IDs.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1019053
When we migrate vms concurrently, there's a chance that libvirtd on
destination assigns the same port for different migrations, which will
lead to migration failure during prepare phase on destination. So we use
virPortAllocator here to solve the problem.
Signed-off-by: Wang Yufei <james.wangyufei@huawei.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can). But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).
Fix up offenders in src/qemu.
* src/qemu/qemu_bridge_filter.h (networkAllowMacOnPort)
(networkDisallowMacOnPort): Use intended type.
* src/qemu/qemu_bridge_filter.c (networkAllowMacOnPort)
(networkDisallowMacOnPort): Likewise.
* src/qemu/qemu_command.c (qemuBuildTPMBackendStr)
(qemuBuildTPMDevStr, qemuBuildCpuArgStr)
(qemuBuildObsoleteAccelArg, qemuBuildMachineArgStr)
(qemuBuildSmpArgStr, qemuBuildNumaArgStr): Likewise.
* src/qemu/qemu_conf.c (qemuSharedDeviceEntryCopy): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSaveImageStartVM): Likewise.
* src/qemu/qemu_hostdev.c
(qemuDomainHostdevNetConfigVirtPortProfile): Likewise.
* src/qemu/qemu_monitor_json.c
(qemuMonitorJSONAttachCharDevCommand): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
The regular save image code has the support to compress images using a
specified algorithm. This was not implemented for external checkpoints
although it shares most of the backend code.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1017227
The regular save image code has the support to compress images using a
specified algorithm. This was not implemented for managed save although
it shares most of the backend code.
This configuration knob is there to override default listen address for
-incoming for all qemu domains.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=994364
Whenever we check for ABI stability, we have new xml (e.g. provided by
user, or obtained from snapshot, whatever) which we compare to old xml
and see if ABI won't break. However, if the new xml was produced via
virDomainGetXMLDesc(..., VIR_DOMAIN_XML_MIGRATABLE) it lacks some
devices, e.g. 'pci-root' controller. Hence, the ABI stability check
fails even though it is stable. Moreover, we can't simply fix
virDomainDefCheckABIStability because removing the correct devices is
task for the driver. For instance, qemu driver wants to remove the usb
controller too, while LXC driver doesn't. That's why we need special
qemu wrapper over virDomainDefCheckABIStability which removes the
correct devices from domain XML, produces MIGRATABLE xml and calls the
check ABI stability function.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The virConnectPtr is passed around loads of nwfilter code in
order to provide it as a parameter to the callback registered
by the virt drivers. None of the virt drivers use this param
though, so it serves no purpose.
Avoiding the need to pass a virConnectPtr means that the
nwfilterStateReload method no longer needs to open a bogus
QEMU driver connection. This addresses a race condition that
can lead to a crash on startup.
The nwfilter driver starts before the QEMU driver and registers
some callbacks with DBus to detect firewalld reload. If the
firewalld reload happens while the QEMU driver is still starting
up though, the nwfilterStateReload method will open a connection
to the partially initialized QEMU driver and cause a crash.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1011330 (case A)
While activeScsiHostdevs and webSocketPorts were allocated in
qemuStateInitialize, they were not freed in qemuStateCleanup.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
