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: Daniel P. Berrange <berrange@redhat.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: Eric Blake <eblake@redhat.com>
With this patch,user can set throttle blkio cgroup for
lxc domain through virsh tool.
Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
This patch introduces virCgroupSetBlkioDeviceReadIops,
virCgroupSetBlkioDeviceWriteIops,
virCgroupSetBlkioDeviceReadBps and
virCgroupSetBlkioDeviceWriteBps,
we can use these interfaces to set up throttle
blkio cgroup for domain.
This patch also adds the new throttle blkio cgroup
elements to the test xml.
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>
the unix socket /var/run/libvirt/lxc/domain.sock is not created
under the selinux context which configured by <seclabel>.
If we try to connect the domain.sock under the selinux context
of domain in virtLXCProcessConnectMonitor,selinux will deny
this connect operation.
type=AVC msg=audit(1387953696.067:662): avc: denied { connectto } for pid=21206 comm="libvirtd" path="/usr/local/var/run/libvirt/lxc/systemd.sock" scontext=unconfined_u:system_r:svirt_lxc_net_t:s0:c770,c848 tcontext=unconfined_u:system_r:unconfined_t:s0-s0:c0.c1023 tclass=unix_stream_socket
fix this problem by creating socket under selinux context of domain.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
The @name variable is VIR_STRDUP()-ed into, but never freed. In fact,
there's no need to duplicate a command line argument since all places
where @name is used expect const char.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Ever since their introduction (commit 1509b80 in v0.5.0 for
virConnectDomainEventRegister, commit 4445723 in v0.8.0 for
virConnectDomainEventDeregisterAny), the event deregistration
functions have been documented as returning 0 on success;
likewise for older registration (only the newer RegisterAny
must return a non-zero callbackID). And now that we are
adding virConnectNetworkEventDeregisterAny for v1.2.1, it
should have the same semantics.
Fortunately, all of the stateful drivers have been obeying
the docs and returning 0, thanks to the way the remote_driver
tracks things (in fact, the RPC wire protocol is unable to
send a return value for DomainEventRegisterAny, at least not
without adding a new RPC number). Well, except for vbox,
which was always failing deregistration, due to failure to
set the return value to anything besides its initial -1.
But for local drivers, such as test:///default, we've been
returning non-zero numbers; worse, the non-zero numbers have
differed over time. For example, in Fedora 12 (libvirt 0.8.2),
calling Register twice would return 0 and 1 [the callbackID
generated under the hood]; while in Fedora 20 (libvirt 1.1.3),
it returns 1 and 2 [the number of callbacks registered for
that event type]. Since we have changed the behavior over
time, and since it differs by local vs. remote, we can safely
argue that no one could have been reasonably relying on any
particular behavior, so we might as well obey the docs, as well
as prepare callers that might deal with older clients to not be
surprised if the docs are not strictly followed.
For consistency, this patch fixes the code for all drivers,
even though it only makes an impact for vbox and for local
drivers. By fixing all drivers, future copy and paste from
a remote driver to a local driver is less likely to
reintroduce the bug.
Finally, update the testsuite to gain some coverage of the
issue for local drivers, including the first test of old-style
domain event registration via function pointer instead of
event id.
* src/libvirt.c (virConnectDomainEventRegister)
(virConnectDomainEventDeregister)
(virConnectDomainEventDeregisterAny): Clarify docs.
* src/libxl/libxl_driver.c (libxlConnectDomainEventRegister)
(libxlConnectDomainEventDeregister)
(libxlConnectDomainEventDeregisterAny): Match documentation.
* src/lxc/lxc_driver.c (lxcConnectDomainEventRegister)
(lxcConnectDomainEventDeregister)
(lxcConnectDomainEventDeregisterAny): Likewise.
* src/test/test_driver.c (testConnectDomainEventRegister)
(testConnectDomainEventDeregister)
(testConnectDomainEventDeregisterAny)
(testConnectNetworkEventDeregisterAny): Likewise.
* src/uml/uml_driver.c (umlConnectDomainEventRegister)
(umlConnectDomainEventDeregister)
(umlConnectDomainEventDeregisterAny): Likewise.
* src/vbox/vbox_tmpl.c (vboxConnectDomainEventRegister)
(vboxConnectDomainEventDeregister)
(vboxConnectDomainEventDeregisterAny): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectDomainEventRegister)
(xenUnifiedConnectDomainEventDeregister)
(xenUnifiedConnectDomainEventDeregisterAny): Likewise.
* src/network/bridge_driver.c
(networkConnectNetworkEventDeregisterAny): Likewise.
* tests/objecteventtest.c (testDomainCreateXMLOld): New test.
(mymain): Run it.
(testDomainCreateXML): Check return values.
Signed-off-by: Eric Blake <eblake@redhat.com>
The libvirt_internal.h header was included by the internal.h header.
This made it painful to add new stuff to the header file that would
require some more specific types. Remove inclusion by internal.h and add
it to appropriate places manually.
This reverts commit aa4619337c.
This patch was accidentally pushed prematurely, and has incorrect
logic for which shutdown methods to attempt.
Signed-off-by: Eric Blake <eblake@redhat.com>
We weren't very consistent in our use of VIR_ERR_NO_SUPPORT; many
users just passed __FUNCTION__ on, while others passed "%s" to
silence over-eager compilers that warn about __FUNCTION__ not
containing any %. It's nicer to route all these uses through
a single macro, so that if we ever need to change the reporting,
we can do it in one place.
I verified that 'virsh -c test:///default qemu-monitor-command test foo'
gives the same error message before and after this patch:
error: this function is not supported by the connection driver: virDomainQemuMonitorCommand
Note that in libvirt.c, we were inconsistent on whether virDomain*
API used virLibConnError() (with VIR_FROM_NONE) or virLibDomainError()
(with VIR_FROM_DOMAIN); this patch unifies these errors to all use
VIR_FROM_NONE, on the grounds that it is unlikely that a caller
learning that a call is unimplemented can do anything in particular
with extra knowledge of which error domain it belongs to.
One particular change to note is virDomainOpenGraphics which was
trying to fail with VIR_ERR_NO_SUPPORT after a failed
VIR_DRV_SUPPORTS_FEATURE check; all other places that fail a
feature check report VIR_ERR_ARGUMENT_UNSUPPORTED.
* src/util/virerror.h (virReportUnsupportedError): New macro.
* src/libvirt-qemu.c: Use new macro.
* src/libvirt-lxc.c: Likewise.
* src/lxc/lxc_driver.c: Likewise.
* src/security/security_manager.c: Likewise.
* src/util/virinitctl.c: Likewise.
* src/libvirt.c: Likewise.
(virDomainOpenGraphics): Use correct error for unsupported feature.
Signed-off-by: Eric Blake <eblake@redhat.com>
Currently, the @flags usage is a bit unclear at first sight to say the
least. There's no need for such unclear code especially when we can
borrow the working code from qemuDomainShutdownFlags().
In addition, this fixes one bug too. If user requested both
VIR_DOMAIN_SHUTDOWN_INITCTL and VIR_DOMAIN_SHUTDOWN_SIGNAL at the same
time, he is basically saying: 'Use the force Luke! If initctl fails try
sending a signal.' But with the current code we don't do that. If
initctl fails for some reason (e.g. inability to write to /dev/initctl)
we don't try sending any signal but fail immediately. To make things
worse, making a domain shutdown with bare _SIGNAL was working by blind
chance of a @rc variable being placed at correct place on the stack so
its initial value was zero.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The function doesn't check whether the request is made for active or
inactive domain. Thus when the domain is not running it still tries
accessing non-existing cgroups (priv->cgroup, which is NULL).
I re-made the function in order for it to work the same way it's qemu
counterpart does.
Reproducer:
1) Define an LXC domain
2) Do 'virsh memtune <domain> --hard-limit 133T'
Backtrace:
Thread 6 (Thread 0x7fffec8c0700 (LWP 26826)):
#0 0x00007ffff70edcc4 in virCgroupPathOfController (group=0x0, controller=3,
key=0x7ffff75734bd "memory.limit_in_bytes", path=0x7fffec8bf718) at util/vircgroup.c:1764
#1 0x00007ffff70e9206 in virCgroupSetValueStr (group=0x0, controller=3,
key=0x7ffff75734bd "memory.limit_in_bytes", value=0x7fffe409f360 "1073741824")
at util/vircgroup.c:669
#2 0x00007ffff70e98b4 in virCgroupSetValueU64 (group=0x0, controller=3,
key=0x7ffff75734bd "memory.limit_in_bytes", value=1073741824) at util/vircgroup.c:740
#3 0x00007ffff70ee518 in virCgroupSetMemory (group=0x0, kb=1048576) at util/vircgroup.c:1904
#4 0x00007ffff70ee675 in virCgroupSetMemoryHardLimit (group=0x0, kb=1048576)
at util/vircgroup.c:1944
#5 0x00005555557d54c8 in lxcDomainSetMemoryParameters (dom=0x7fffe40cc420,
params=0x7fffe409f100, nparams=1, flags=0) at lxc/lxc_driver.c:774
#6 0x00007ffff72c20f9 in virDomainSetMemoryParameters (domain=0x7fffe40cc420,
params=0x7fffe409f100, nparams=1, flags=0) at libvirt.c:4051
#7 0x000055555561365f in remoteDispatchDomainSetMemoryParameters (server=0x555555eb7e00,
client=0x555555ec4b10, msg=0x555555eb94e0, rerr=0x7fffec8bfb70, args=0x7fffe40b8510)
at remote_dispatch.h:7621
#8 0x00005555556133fd in remoteDispatchDomainSetMemoryParametersHelper (server=0x555555eb7e00,
client=0x555555ec4b10, msg=0x555555eb94e0, rerr=0x7fffec8bfb70, args=0x7fffe40b8510,
ret=0x7fffe40b84f0) at remote_dispatch.h:7591
#9 0x00007ffff73b293f in virNetServerProgramDispatchCall (prog=0x555555ec3ae0,
server=0x555555eb7e00, client=0x555555ec4b10, msg=0x555555eb94e0)
at rpc/virnetserverprogram.c:435
#10 0x00007ffff73b207f in virNetServerProgramDispatch (prog=0x555555ec3ae0,
server=0x555555eb7e00, client=0x555555ec4b10, msg=0x555555eb94e0)
at rpc/virnetserverprogram.c:305
#11 0x00007ffff73a4d2c in virNetServerProcessMsg (srv=0x555555eb7e00, client=0x555555ec4b10,
prog=0x555555ec3ae0, msg=0x555555eb94e0) at rpc/virnetserver.c:165
#12 0x00007ffff73a4e8d in virNetServerHandleJob (jobOpaque=0x555555ec3e30, opaque=0x555555eb7e00)
at rpc/virnetserver.c:186
#13 0x00007ffff7187f3f in virThreadPoolWorker (opaque=0x555555eb7ac0) at util/virthreadpool.c:144
#14 0x00007ffff718733a in virThreadHelper (data=0x555555eb7890) at util/virthreadpthread.c:161
#15 0x00007ffff468ed89 in start_thread (arg=0x7fffec8c0700) at pthread_create.c:308
#16 0x00007ffff3da26bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
The function doesn't check whether the request is made for active or
inactive domain. Thus when the domain is not running it still tries
accessing non-existing cgroups (priv->cgroup, which is NULL).
I re-made the function in order for it to work the same way it's qemu
counterpart does.
Reproducer:
1) Define an LXC domain
2) Do 'virsh memtune <domain>'
Backtrace:
Thread 6 (Thread 0x7fffec8c0700 (LWP 13387)):
#0 0x00007ffff70edcc4 in virCgroupPathOfController (group=0x0, controller=3,
key=0x7ffff75734bd "memory.limit_in_bytes", path=0x7fffec8bf750) at util/vircgroup.c:1764
#1 0x00007ffff70e958c in virCgroupGetValueStr (group=0x0, controller=3,
key=0x7ffff75734bd "memory.limit_in_bytes", value=0x7fffec8bf7c0) at util/vircgroup.c:705
#2 0x00007ffff70e9d29 in virCgroupGetValueU64 (group=0x0, controller=3,
key=0x7ffff75734bd "memory.limit_in_bytes", value=0x7fffec8bf810) at util/vircgroup.c:804
#3 0x00007ffff70ee706 in virCgroupGetMemoryHardLimit (group=0x0, kb=0x7fffec8bf8a8)
at util/vircgroup.c:1962
#4 0x00005555557d590f in lxcDomainGetMemoryParameters (dom=0x7fffd40024a0,
params=0x7fffd40027a0, nparams=0x7fffec8bfa24, flags=0) at lxc/lxc_driver.c:826
#5 0x00007ffff72c28d3 in virDomainGetMemoryParameters (domain=0x7fffd40024a0,
params=0x7fffd40027a0, nparams=0x7fffec8bfa24, flags=0) at libvirt.c:4137
#6 0x000055555563714d in remoteDispatchDomainGetMemoryParameters (server=0x555555eb7e00,
client=0x555555ebaef0, msg=0x555555ebb3e0, rerr=0x7fffec8bfb70, args=0x7fffd40024e0,
ret=0x7fffd4002420) at remote.c:1895
#7 0x00005555556052c4 in remoteDispatchDomainGetMemoryParametersHelper (server=0x555555eb7e00,
client=0x555555ebaef0, msg=0x555555ebb3e0, rerr=0x7fffec8bfb70, args=0x7fffd40024e0,
ret=0x7fffd4002420) at remote_dispatch.h:4050
#8 0x00007ffff73b293f in virNetServerProgramDispatchCall (prog=0x555555ec3ae0,
server=0x555555eb7e00, client=0x555555ebaef0, msg=0x555555ebb3e0)
at rpc/virnetserverprogram.c:435
#9 0x00007ffff73b207f in virNetServerProgramDispatch (prog=0x555555ec3ae0,
server=0x555555eb7e00, client=0x555555ebaef0, msg=0x555555ebb3e0)
at rpc/virnetserverprogram.c:305
#10 0x00007ffff73a4d2c in virNetServerProcessMsg (srv=0x555555eb7e00, client=0x555555ebaef0,
prog=0x555555ec3ae0, msg=0x555555ebb3e0) at rpc/virnetserver.c:165
#11 0x00007ffff73a4e8d in virNetServerHandleJob (jobOpaque=0x555555ebc7e0, opaque=0x555555eb7e00)
at rpc/virnetserver.c:186
#12 0x00007ffff7187f3f in virThreadPoolWorker (opaque=0x555555eb7ac0) at util/virthreadpool.c:144
#13 0x00007ffff718733a in virThreadHelper (data=0x555555eb7890) at util/virthreadpthread.c:161
#14 0x00007ffff468ed89 in start_thread (arg=0x7fffec8c0700) at pthread_create.c:308
#15 0x00007ffff3da26bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Systemd specified that any /dev/pts/NNN device on which it
is expected to spawn a agetty login, should be listed in
the 'container_ttys' env variable. It should just contain
the relative paths, eg 'pts/0' not '/dev/pts/0' and should
be space separated.
http://cgit.freedesktop.org/systemd/systemd/commit/?id=1d97ff7dd71902a5604c2fed8964925d54e09de9
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently, if virFileMakePath() fails, the @ret is left initialized from
virAsprintf() just a few lines above leading to a wrong return value of
zero whereas -1 should be returned.
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
When setting up filesystems backed by block devices or file
images, the SELinux mount options must be used to ensure the
correct context is set
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Move the code for lxcContainerGetSubtree into the virfile
module creating 2 new functions
int virFileGetMountSubtree(const char *mtabpath,
const char *prefix,
char ***mountsret,
size_t *nmountsret);
int virFileGetMountReverseSubtree(const char *mtabpath,
const char *prefix,
char ***mountsret,
size_t *nmountsret);
Add a new virfiletest.c test case to validate the new code.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Also after commit 5ff9d8a65ce80efb509ce4e8051394e9ed2cd942
vfs: Lock in place mounts from more privileged users,
unprivileged user has no rights to umount the mounts that
inherited from parent mountns.
right now, I have no good idea to fix this problem, we need
to do more research. this patch just skip unmounting these
mounts for shared root.
BTW, I think when libvirt lxc enables user namespace, the
configuation that shares root with host is very rara.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
After kernel commit 5ff9d8a65ce80efb509ce4e8051394e9ed2cd942
vfs: Lock in place mounts from more privileged users,
unprivileged user has no rights to move the mounts that
inherited from parent mountns. we use this feature to move
the /stateDir/domain-name.{dev, devpts} to the /dev/ and
/dev/pts directroy of container. this commit breaks libvirt lxc.
this patch changes the behavior to bind these mounts when
user namespace is enabled and move these mounts when user
namespace is disabled.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Most of our code base uses space after comma but not before;
fix the remaining uses before adding a syntax check.
* src/lxc/lxc_container.c: Consistently use commas.
* src/openvz/openvz_driver.c: Likewise.
* src/openvz/openvz_util.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/test/test_driver.c: Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Without a 'return 0' in the stub lxcStartFuse() method, the
compiler warns:
lxc/lxc_fuse.c:374: error: control reaches end of non-void function
[-Wreturn-type]
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The glibc setxid is supposed to be async signal safe, but
libc developers confirm that it is not. This causes a problem
when libvirt_lxc starts the FUSE thread and then runs clone()
to start the container. If the clone() was done before the
FUSE thread has completely started up, then the container
will hang in setxid after clone().
The fix is to avoid creating any threads until after the
container has been clone()'d. By avoiding any threads in
the parent, the child is no longer required to run in an
async signal safe context, and we thus avoid the glibc
bug.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If the host side of an LXC container console disconnected
and the guest side continued to write data, until the PTY
buffer filled up, the LXC controller would busy wait. It
would repeatedly see POLLHUP from poll() and not disable
the watch.
This was due to some bogus logic detecting blocking
conditions. Upon seeing a POLLHUP we must disable all
reading & writing from the PTY, and setup the epoll to
wake us up again when the connection comes back.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently we were storing domain feature flags in a bit field as the
they were either enabled or disabled. New features such as paravirtual
spinlocks however can be tri-state as the default option may depend on
hypervisor version.
To allow storing tri-state feature state in the same place instead of
having to declare dedicated variables for each feature this patch
refactors the bit field to an array.
Currently the LXC container tries to skip selinux/securityfs
mounts if the directory does not exist in the filesystem,
or if SELinux is disabled.
The former check is flawed because the /sys/fs/selinux
or /sys/kernel/securityfs directories may exist in sysfs
even if the mount type is disabled. Instead of just doing
an access() check, use an virFileIsMounted() to see if
the FS is actually present in the host OS. This also
avoids the need to check is_selinux_enabled().
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Some mounts must be skipped if running inside a user namespace,
since the kernel forbids their use. Instead of strcmp'ing the
filesystem type in the body of the loop, set an explicit flag
in the lxcBasicMounts table.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently the lxcBasicMounts array has separate entries for
most mounts, to reflect that we must do a separate mount
operation to make mounts read-only. Remove the duplicate
entries and instead set the MS_RDONLY flag against the main
entry. Then change lxcContainerMountBasicFS to look for the
MS_RDONLY flag, mask it out & do a separate bind mount.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The 'srcpath' variable is initialized from 'mnt->src' and never
changed thereafter. Some places continue to use 'mnt->src' and
others use 'srcpath'. Remove the pointless 'srcpath' variable
and use 'mnt->src' everywhere.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virLXCBasicMountInfo struct contains a 'char *opts'
field passed onto the mount() syscall. Every entry in the
list sets this to NULL though, so it can be removed to
simplify life.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Expand the "secmodel" XML fragment of "host" with a sequence of
baselabel's which describe the default security context used by
libvirt with a specific security model and virtualization type:
<secmodel>
<model>selinux</model>
<doi>0</doi>
<baselabel type='kvm'>system_u:system_r:svirt_t:s0</baselabel>
<baselabel type='qemu'>system_u:system_r:svirt_tcg_t:s0</baselabel>
</secmodel>
<secmodel>
<model>dac</model>
<doi>0</doi>
<baselabel type='kvm'>107:107</baselabel>
<baselabel type='qemu'>107:107</baselabel>
</secmodel>
"baselabel" is driver-specific information, e.g. in the DAC security
model, it indicates USER_ID:GROUP_ID.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The lxcContainerSetID() method prints a misleading log
message about setting the uid/gid when no ID map is
present in the XML config. Skip the debug message in
this case.
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.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>
Unconditional use of getenv is not secure in setuid env.
While not all libvirt code runs in a setuid env (since
much of it only exists inside libvirtd) this is not always
clear to developers. So make all the code paranoid, even
if it only ever runs inside libvirtd.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When running setuid, we must be careful about what env vars
we allow commands to inherit from us. Replace the
virCommandAddEnvPass function with two new ones which do
filtering
virCommandAddEnvPassAllowSUID
virCommandAddEnvPassBlockSUID
And make virCommandAddEnvPassCommon use the appropriate
ones
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A typo in the setup of NBD backed filesystems meant the
/dev/nbdN device would not be added to the cgroups device
ACL.
Signed-off-by: Daniel P. Berrange <berrange@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 all remaining offenders.
* src/lxc/lxc_process.c (virLXCProcessSetupInterfaceBridged): Drop
needless const.
* src/uml/uml_driver.c (umlMonitorCommand): Use intended type.
(umlMonitorAddress): Fix fallout.
* src/xen/xm_internal.c (xenXMDomainSearchForUUID): Use intended type.
Signed-off-by: Eric Blake <eblake@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/conf/domain_conf, and their fallout.
Several things to note: virObjectLock() requires a non-const
argument; if this were C++, we could treat the locking field
as 'mutable' and allow locking an otherwise 'const' object, but
that is a more invasive change, so I instead dropped attempts
to be const-correct on domain lookup. virXMLPropString and
friends require a non-const xmlNodePtr - this is because libxml2
is not a const-correct library. We could make the src/util/virxml
wrappers cast away const, but I figured it was easier to not
try to mark xmlNodePtr as const. Finally, virDomainDeviceDefCopy
was a rather hard conversion - it calls virDomainDeviceDefPostParse,
which in turn in the xen driver was actually modifying the domain
outside of the current device being visited. We should not be
adding a device on the first per-device callback, but waiting until
after all per-device callbacks are complete.
* src/conf/domain_conf.h (virDomainObjListFindByID)
(virDomainObjListFindByUUID, virDomainObjListFindByName)
(virDomainObjAssignDef, virDomainObjListAdd): Drop attempt at
const.
(virDomainDeviceDefCopy): Use intended type.
(virDomainDeviceDefParse, virDomainDeviceDefPostParseCallback)
(virDomainVideoDefaultType, virDomainVideoDefaultRAM)
(virDomainChrGetDomainPtrs): Make const-correct.
* src/conf/domain_conf.c (virDomainObjListFindByID)
(virDomainObjListFindByUUID, virDomainObjListFindByName)
(virDomainDeviceDefCopy, virDomainObjListAdd)
(virDomainObjAssignDef, virDomainHostdevSubsysUsbDefParseXML)
(virDomainHostdevSubsysPciOrigStatesDefParseXML)
(virDomainHostdevSubsysPciDefParseXML)
(virDomainHostdevSubsysScsiDefParseXML)
(virDomainControllerModelTypeFromString)
(virDomainTPMDefParseXML, virDomainTimerDefParseXML)
(virDomainSoundCodecDefParseXML, virDomainSoundDefParseXML)
(virDomainWatchdogDefParseXML, virDomainRNGDefParseXML)
(virDomainMemballoonDefParseXML, virDomainNVRAMDefParseXML)
(virSysinfoParseXML, virDomainVideoAccelDefParseXML)
(virDomainVideoDefParseXML, virDomainHostdevDefParseXML)
(virDomainRedirdevDefParseXML)
(virDomainRedirFilterUsbDevDefParseXML)
(virDomainRedirFilterDefParseXML, virDomainIdMapEntrySort)
(virDomainIdmapDefParseXML, virDomainVcpuPinDefParseXML)
(virDiskNameToBusDeviceIndex, virDomainDeviceDefCopy)
(virDomainVideoDefaultType, virDomainHostdevAssignAddress)
(virDomainDeviceDefPostParseInternal, virDomainDeviceDefPostParse)
(virDomainChrGetDomainPtrs, virDomainControllerSCSINextUnit)
(virDomainSCSIDriveAddressIsUsed)
(virDomainDriveAddressIsUsedByDisk)
(virDomainDriveAddressIsUsedByHostdev): Fix fallout.
* src/openvz/openvz_driver.c (openvzDomainDeviceDefPostParse):
Likewise.
* src/libxl/libxl_domain.c (libxlDomainDeviceDefPostParse):
Likewise.
* src/qemu/qemu_domain.c (qemuDomainDeviceDefPostParse)
(qemuDomainDefaultNetModel): Likewise.
* src/lxc/lxc_domain.c (virLXCDomainDeviceDefPostParse):
Likewise.
* src/uml/uml_driver.c (umlDomainDeviceDefPostParse): Likewise.
* src/xen/xen_driver.c (xenDomainDeviceDefPostParse): Split...
(xenDomainDefPostParse): ...since per-device callback is not the
time to be adding a device.
Signed-off-by: Eric Blake <eblake@redhat.com>
Make the virLXCProcessReadLogOutputData method ignore the log
lines about the container startup argv, ignore the generic
error message from libvirt_lxc when lxcContainerMain fails
and skip over blank lines.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The lxcContainerResolveSymlinks method merely logged some errors
as debug messages, rather than reporting them as proper errors.
This meant startup failures were not diagnosed at all.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Ensure the lxcContainerMain method reports any errors that
occur during setup to stderr, where libvirtd will pick them
up.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
In Fedora 20, libvirt_lxc crashes immediately at startup with a
trace
#0 0x00007f0cddb653ec in free () from /lib64/libc.so.6
#1 0x00007f0ce0e16f4a in virFree (ptrptr=ptrptr@entry=0x7f0ce1830058) at util/viralloc.c:580
#2 0x00007f0ce0e2764b in virResetError (err=0x7f0ce1830030) at util/virerror.c:354
#3 0x00007f0ce0e27a5a in virResetLastError () at util/virerror.c:387
#4 0x00007f0ce0e28858 in virEventRegisterDefaultImpl () at util/virevent.c:233
#5 0x00007f0ce0db47c6 in main (argc=11, argv=0x7fff4596c328) at lxc/lxc_controller.c:2352
Normally virInitialize calls virErrorInitialize and
virThreadInitialize, but we don't link to libvirt.so
in libvirt_lxc, and nor did we ever call the error
or thread initializers.
I have absolutely no idea how this has ever worked, let alone
what caused it to stop working in Fedora 20.
In addition not all code paths from virLogSetFromEnv will
ensure virLogInitialize is called correctly, which is another
possible crash scenario.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The LXC code would read the log file if an LXC guest failed to
startup. There were a number of failure cases where the guest
will not start and libvirtd never gets as far as looking at the
log file.
Fix this by replacing some earlier generic errors with messages
from the log.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The LXC controller main() method initialized 'rc' to 1
rather than '-1'. In the cleanup path it will print any
error to stderr, if-and-only-if rc < 0. Hence the incorrect
initialization caused errors to be lost.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The LXC controller uses dbus to talk to systemd to create
cgroups. This means that each LXC controller instance has
a dbus connection. The DBus daemon is limited to 256
connections by default and we want to be able to run many
1000 of containers.
While the dbus limit could be raised in the config files,
it is simpler to make libvirt LXC controller close its
dbus connection once everything is configured.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Since 76b644c when the support for RAM filesystems was introduced,
libvirt accepted the following XML:
<source usage='1024' unit='KiB'/>
This was parsed correctly and internally stored in bytes, but it
was formatted as (with an extra 's'):
<source usage='1024' units='KiB'/>
When read again, this was treated as if the units were missing,
meaning libvirt was unable to parse its own XML correctly.
The usage attribute was documented as being in KiB, but it was not
scaled if the unit was missing. Transient domains still worked,
because this was balanced by an extra 'k' in the mount options.
This patch:
Changes the parser to use 'units' instead of 'unit', as the latter
was never documented (fixing persistent domains) and some programs
(libvirt-glib, libvirt-sandbox) already parse the 'units' attribute.
Removes the extra 'k' from the tmpfs mount options, which is needed
because now we parse our own XML correctly.
Changes the default input unit to KiB to match documentation, fixing:
https://bugzilla.redhat.com/show_bug.cgi?id=1015689
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>
If veth device allocation has a fatal error, the veths
array may contain NULL device names. Avoid calling the
virNetDevVethDelete function on such names.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
During container cleanup there is a race where the kernel may
have destroyed the veth device before we try to set it offline.
This causes log error messages. Given that we're about to
delete the device entirely, setting it offline is pointless.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We forgot to do cleanup when lxcContainerMountFSTmpfs
failed to bind fs as read-only.
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The problem is described by [0] but its effect on libvirt is that
starting a container with a full distro running systemd after having
stopped it simply fails.
The container cleanup now calls the machined Terminate function to make
sure that everything is in order for the next run.
[0]: https://bugs.freedesktop.org/show_bug.cgi?id=68370
If a dir does not exist, raise an immediate error in logs
rather than letting virFileResolveAllLinks fail, since this
gives better error reporting to the user.
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
When FUSE is enabled, the LXC container is setup with
a custom /proc/meminfo file. This file uses "KB" as a
suffix, rather than "kB" which is the kernel's style.
Fix this inconsistency to avoid confusing apps.
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Right now we mount selinuxfs even user namespace is enabled and
ignore the error. But we shouldn't ignore these errors when user
namespace is not enabled.
This patch skips mounting selinuxfs when user namespace enabled.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
If the guest is configured with
<filesystem type='mount'>
<source dir='/'/>
<target dir='/'/>
<readonly/>
</filesystem>
Then any submounts under / should also end up readonly, except
for those setup as basic mounts. eg if the user has /home on a
separate volume, they'd expect /home to be readonly, but we
should not touch the /sys, /proc, etc dirs we setup ourselves.
Users can selectively make sub-mounts read-write again by
simply listing them as new mounts without the <readonly>
flag set
<filesystem type='mount'>
<source dir='/home'/>
<target dir='/home'/>
</filesystem>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Move the array of basic mounts out of the lxcContainerMountBasicFS
function, to a global variable. This is to allow it to be referenced
by other methods wanting to know what the basic mount paths are.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The devpts, dev and fuse filesystems are mounted temporarily.
there is no need to export them to container if container shares
the root directory with host.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Right now, securityfs is disallowed to be mounted in non-initial
user namespace, so we must avoid trying to mount securityfs in
a container which has user namespace enabled.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
If booting a container with a root FS that isn't the host's
root, we must ensure that the /dev mount point exists.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The lxcContainerMountFSBlockAuto method can be used to mount the
initial root filesystem, so it cannot assume a prefix of /.oldroot.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If securityfs is available on the host, we should ensure to
mount it read-only in the container. This will avoid systemd
trying to mount it during startup causing SELinux AVCs.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This configuration knob lets user to set the length of queue of
connection requests waiting to be accept()-ed by the daemon. IOW, it
just controls the @backlog passed to listen:
int listen(int sockfd, int backlog);
If upgrading from a libvirt that is older than 1.0.5, we can
not assume that vm->def->resource is non-NULL. This bogus
assumption caused libvirtd to crash
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Make the virCgroupNewMachine method try to use systemd-machined
first. If that fails, then fallback to using the traditional
cgroup setup code path.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
By setting the default partition in libvirt_lxc it is not
visible when querying the live XML. Move setting of the
default partition into libvirtd virLXCProcessStart
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of requiring drivers to use a combination of calls
to virCgroupNewDetect and virCgroupIsValidMachine, combine
the two into virCgroupNewDetectMachine
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
There's a race in lxc driver causing a deadlock. If a domain is
destroyed immediately after started, the deadlock can occur. When domain
is started, the even loop tries to connect to the monitor. If the
connecting succeeds, virLXCProcessMonitorInitNotify() is called with
@mon->client locked. The first thing that callee does, is
virObjectLock(vm). So the order of locking is: 1) @mon->client, 2) @vm.
However, if there's another thread executing virDomainDestroy on the
very same domain, the first thing done here is locking the @vm. Then,
the corresponding libvirt_lxc process is killed and monitor is closed
via calling virLXCMonitorClose(). This callee tries to lock @mon->client
too. So the order is reversed to the first case. This situation results
in deadlock and unresponsive libvirtd (since the eventloop is involved).
The proper solution is to unlock the @vm in virLXCMonitorClose prior
entering virNetClientClose(). See the backtrace as follows:
Thread 25 (Thread 0x7f1b7c9b8700 (LWP 16312)):
0 0x00007f1b80539714 in __lll_lock_wait () from /lib64/libpthread.so.0
1 0x00007f1b8053516c in _L_lock_516 () from /lib64/libpthread.so.0
2 0x00007f1b80534fbb in pthread_mutex_lock () from /lib64/libpthread.so.0
3 0x00007f1b82a637cf in virMutexLock (m=0x7f1b3c0038d0) at util/virthreadpthread.c:85
4 0x00007f1b82a4ccf2 in virObjectLock (anyobj=0x7f1b3c0038c0) at util/virobject.c:320
5 0x00007f1b82b861f6 in virNetClientCloseInternal (client=0x7f1b3c0038c0, reason=3) at rpc/virnetclient.c:696
6 0x00007f1b82b862f5 in virNetClientClose (client=0x7f1b3c0038c0) at rpc/virnetclient.c:721
7 0x00007f1b6ee12500 in virLXCMonitorClose (mon=0x7f1b3c007210) at lxc/lxc_monitor.c:216
8 0x00007f1b6ee129f0 in virLXCProcessCleanup (driver=0x7f1b68100240, vm=0x7f1b680ceb70, reason=VIR_DOMAIN_SHUTOFF_DESTROYED) at lxc/lxc_process.c:174
9 0x00007f1b6ee14106 in virLXCProcessStop (driver=0x7f1b68100240, vm=0x7f1b680ceb70, reason=VIR_DOMAIN_SHUTOFF_DESTROYED) at lxc/lxc_process.c:710
10 0x00007f1b6ee1aa36 in lxcDomainDestroyFlags (dom=0x7f1b5c002560, flags=0) at lxc/lxc_driver.c:1291
11 0x00007f1b6ee1ab1a in lxcDomainDestroy (dom=0x7f1b5c002560) at lxc/lxc_driver.c:1321
12 0x00007f1b82b05be5 in virDomainDestroy (domain=0x7f1b5c002560) at libvirt.c:2303
13 0x00007f1b835a7e85 in remoteDispatchDomainDestroy (server=0x7f1b857419d0, client=0x7f1b8574ae40, msg=0x7f1b8574acf0, rerr=0x7f1b7c9b7c30, args=0x7f1b5c004a50) at remote_dispatch.h:3143
14 0x00007f1b835a7d78 in remoteDispatchDomainDestroyHelper (server=0x7f1b857419d0, client=0x7f1b8574ae40, msg=0x7f1b8574acf0, rerr=0x7f1b7c9b7c30, args=0x7f1b5c004a50, ret=0x7f1b5c0029e0) at remote_dispatch.h:3121
15 0x00007f1b82b93704 in virNetServerProgramDispatchCall (prog=0x7f1b8573af90, server=0x7f1b857419d0, client=0x7f1b8574ae40, msg=0x7f1b8574acf0) at rpc/virnetserverprogram.c:435
16 0x00007f1b82b93263 in virNetServerProgramDispatch (prog=0x7f1b8573af90, server=0x7f1b857419d0, client=0x7f1b8574ae40, msg=0x7f1b8574acf0) at rpc/virnetserverprogram.c:305
17 0x00007f1b82b8c0f6 in virNetServerProcessMsg (srv=0x7f1b857419d0, client=0x7f1b8574ae40, prog=0x7f1b8573af90, msg=0x7f1b8574acf0) at rpc/virnetserver.c:163
18 0x00007f1b82b8c1da in virNetServerHandleJob (jobOpaque=0x7f1b8574dca0, opaque=0x7f1b857419d0) at rpc/virnetserver.c:184
19 0x00007f1b82a64158 in virThreadPoolWorker (opaque=0x7f1b8573cb10) at util/virthreadpool.c:144
20 0x00007f1b82a63ae5 in virThreadHelper (data=0x7f1b8574b9f0) at util/virthreadpthread.c:161
21 0x00007f1b80532f4a in start_thread () from /lib64/libpthread.so.0
22 0x00007f1b7fc4f20d in clone () from /lib64/libc.so.6
Thread 1 (Thread 0x7f1b83546740 (LWP 16297)):
0 0x00007f1b80539714 in __lll_lock_wait () from /lib64/libpthread.so.0
1 0x00007f1b8053516c in _L_lock_516 () from /lib64/libpthread.so.0
2 0x00007f1b80534fbb in pthread_mutex_lock () from /lib64/libpthread.so.0
3 0x00007f1b82a637cf in virMutexLock (m=0x7f1b680ceb80) at util/virthreadpthread.c:85
4 0x00007f1b82a4ccf2 in virObjectLock (anyobj=0x7f1b680ceb70) at util/virobject.c:320
5 0x00007f1b6ee13bd7 in virLXCProcessMonitorInitNotify (mon=0x7f1b3c007210, initpid=4832, vm=0x7f1b680ceb70) at lxc/lxc_process.c:601
6 0x00007f1b6ee11fd3 in virLXCMonitorHandleEventInit (prog=0x7f1b3c001f10, client=0x7f1b3c0038c0, evdata=0x7f1b8574a7d0, opaque=0x7f1b3c007210) at lxc/lxc_monitor.c:109
7 0x00007f1b82b8a196 in virNetClientProgramDispatch (prog=0x7f1b3c001f10, client=0x7f1b3c0038c0, msg=0x7f1b3c003928) at rpc/virnetclientprogram.c:259
8 0x00007f1b82b87030 in virNetClientCallDispatchMessage (client=0x7f1b3c0038c0) at rpc/virnetclient.c:1019
9 0x00007f1b82b876bb in virNetClientCallDispatch (client=0x7f1b3c0038c0) at rpc/virnetclient.c:1140
10 0x00007f1b82b87d41 in virNetClientIOHandleInput (client=0x7f1b3c0038c0) at rpc/virnetclient.c:1312
11 0x00007f1b82b88f51 in virNetClientIncomingEvent (sock=0x7f1b3c0044e0, events=1, opaque=0x7f1b3c0038c0) at rpc/virnetclient.c:1832
12 0x00007f1b82b9e1c8 in virNetSocketEventHandle (watch=3321, fd=54, events=1, opaque=0x7f1b3c0044e0) at rpc/virnetsocket.c:1695
13 0x00007f1b82a272cf in virEventPollDispatchHandles (nfds=21, fds=0x7f1b8574ded0) at util/vireventpoll.c:498
14 0x00007f1b82a27af2 in virEventPollRunOnce () at util/vireventpoll.c:645
15 0x00007f1b82a25a61 in virEventRunDefaultImpl () at util/virevent.c:273
16 0x00007f1b82b8e97e in virNetServerRun (srv=0x7f1b857419d0) at rpc/virnetserver.c:1097
17 0x00007f1b8359db6b in main (argc=2, argv=0x7ffff98dbaa8) at libvirtd.c:1512
Commit 'c8695053' resulted in the following:
Coverity error seen in the output:
ERROR: REVERSE_INULL
FUNCTION: lxcProcessAutoDestroy
Due to the 'dom' being checked before 'dom->persistent' since 'dom'
is already dereferenced prior to that.
Currently the LXC driver creates the VM's cgroup prior to
forking, and then libvirt_lxc moves the child process
into the cgroup. This won't work with systemd whose APIs
do the creation of cgroups + attachment of processes atomically.
Fortunately we simply move the entire cgroups setup into
the libvirt_lxc child process. We make it take place before
fork'ing into the background, so by the time virCommandRun
returns in the LXC driver, the cgroup is guaranteed to be
present.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Use the new virCgroupNewDetect function to determine cgroup
placement of existing running VMs. This will allow the legacy
cgroups creation APIs to be removed entirely
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Convert the remaining methods in vircgroup.c to report errors
instead of returning errno values.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If no explicit driver is set for an image backed filesystem,
set it to use the loop driver (if raw) or nbd driver (if
non-raw)
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A couple of places in LXC setup for filesystems did not do
a "goto cleanup" after reporting errors. While fixing this,
also add in many more debug statements to aid troubleshooting
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
With the majority of fields in the virLXCDriverPtr struct
now immutable or self-locking, there is no need for practically
any methods to be using the LXC driver lock. Only a handful
of helper APIs now need it.
The activeUsbHostdevs item in LXCDriver are lockable, but the lock has
to be called explicitly. Call the virObject(Un)Lock() in order to
achieve mutual exclusion once lxcDriverLock is removed.
The 'driver->caps' pointer can be changed on the fly. Accessing
it currently requires the global driver lock. Isolate this
access in a single helper, so a future patch can relax the
locking constraints.
Currently the virLXCDriverPtr struct contains an wide variety
of data with varying access needs. Move all the static config
data into a dedicated virLXCDriverConfigPtr object. The only
locking requirement is to hold the driver lock, while obtaining
an instance of virLXCDriverConfigPtr. Once a reference is held
on the config object, it can be used completely lockless since
it is immutable.
NB, not all APIs correctly hold the driver lock while getting
a reference to the config object in this patch. This is safe
for now since the config is never updated on the fly. Later
patches will address this fully.
Merge the virCommandPreserveFD / virCommandTransferFD methods
into a single virCommandPasFD method, and use a new
VIR_COMMAND_PASS_FD_CLOSE_PARENT to indicate their difference
in behaviour
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Wire up the new virDomainCreate{XML}WithFiles methods in the
LXC driver, so that FDs get passed down to the init process.
The lxc_container code needs to do a little dance in order
to renumber the file descriptors it receives into linear
order, starting from STDERR_FILENO + 1.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Commit 75c1256 states that virGetGroupList must not be called
between fork and exec, then commit ee777e99 promptly violated
that for lxc.
Patch originally posted by Eric Blake <eblake@redhat.com>.
Currently, if the primary security driver is 'none', we skip
initializing caps->host.secModels. This means, later, when LXC domain
XML is parsed and <seclabel type='none'/> is found (see
virSecurityLabelDefsParseXML), the model name is not copied to the
seclabel. This leads to subsequent crash in virSecurityManagerGenLabel
where we call STREQ() over the model (note, that we are expecting model
to be !NULL).
Otherwise the container will fail to start if we
enable user namespace, since there is no rights to
do mknod in uninit user namespace.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
lxc driver will use this function to change the owner
of hot added devices.
Move virLXCControllerChown to lxc_container.c and Rename
it to lxcContainerChown.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
When failing to start a container due to inaccessible root
filesystem path, we did not log any meaningful error. Add a
few debug statements to assist diagnosis
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=964358
POSIX states that multi-threaded apps should not use functions
that are not async-signal-safe between fork and exec, yet we
were using getpwuid_r and initgroups. Although rare, it is
possible to hit deadlock in the child, when it tries to grab
a mutex that was already held by another thread in the parent.
I actually hit this deadlock when testing multiple domains
being started in parallel with a command hook, with the following
backtrace in the child:
Thread 1 (Thread 0x7fd56bbf2700 (LWP 3212)):
#0 __lll_lock_wait ()
at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:136
#1 0x00007fd5761e7388 in _L_lock_854 () from /lib64/libpthread.so.0
#2 0x00007fd5761e7257 in __pthread_mutex_lock (mutex=0x7fd56be00360)
at pthread_mutex_lock.c:61
#3 0x00007fd56bbf9fc5 in _nss_files_getpwuid_r (uid=0, result=0x7fd56bbf0c70,
buffer=0x7fd55c2a65f0 "", buflen=1024, errnop=0x7fd56bbf25b8)
at nss_files/files-pwd.c:40
#4 0x00007fd575aeff1d in __getpwuid_r (uid=0, resbuf=0x7fd56bbf0c70,
buffer=0x7fd55c2a65f0 "", buflen=1024, result=0x7fd56bbf0cb0)
at ../nss/getXXbyYY_r.c:253
#5 0x00007fd578aebafc in virSetUIDGID (uid=0, gid=0) at util/virutil.c:1031
#6 0x00007fd578aebf43 in virSetUIDGIDWithCaps (uid=0, gid=0, capBits=0,
clearExistingCaps=true) at util/virutil.c:1388
#7 0x00007fd578a9a20b in virExec (cmd=0x7fd55c231f10) at util/vircommand.c:654
#8 0x00007fd578a9dfa2 in virCommandRunAsync (cmd=0x7fd55c231f10, pid=0x0)
at util/vircommand.c:2247
#9 0x00007fd578a9d74e in virCommandRun (cmd=0x7fd55c231f10, exitstatus=0x0)
at util/vircommand.c:2100
#10 0x00007fd56326fde5 in qemuProcessStart (conn=0x7fd53c000df0,
driver=0x7fd55c0dc4f0, vm=0x7fd54800b100, migrateFrom=0x0, stdin_fd=-1,
stdin_path=0x0, snapshot=0x0, vmop=VIR_NETDEV_VPORT_PROFILE_OP_CREATE,
flags=1) at qemu/qemu_process.c:3694
...
The solution is to split the work of getpwuid_r/initgroups into the
unsafe portions (getgrouplist, called pre-fork) and safe portions
(setgroups, called post-fork).
* src/util/virutil.h (virSetUIDGID, virSetUIDGIDWithCaps): Adjust
signature.
* src/util/virutil.c (virSetUIDGID): Add parameters.
(virSetUIDGIDWithCaps): Adjust clients.
* src/util/vircommand.c (virExec): Likewise.
* src/util/virfile.c (virFileAccessibleAs, virFileOpenForked)
(virDirCreate): Likewise.
* src/security/security_dac.c (virSecurityDACSetProcessLabel):
Likewise.
* src/lxc/lxc_container.c (lxcContainerSetID): Likewise.
* configure.ac (AC_CHECK_FUNCS_ONCE): Check for setgroups, not
initgroups.
Signed-off-by: Eric Blake <eblake@redhat.com>
Recent changes uncovered a NEGATIVE_RETURNS in the return from sysconf()
when processing a for loop in virtTestCaptureProgramExecChild() in
testutils.c
Code review uncovered 3 other code paths with the same condition that
weren't found by Covirity, so fixed those as well.
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Create parent directroy for hostdev automatically when we
start a lxc domain or attach a hostdev to a lxc domain.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
This helper function is used to create parent directory for
the hostdev which will be added to the container. If the
parent directory of this hostdev doesn't exist, the mknod of
the hostdev will fail. eg with /dev/net/tun
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Many applications use /dev/tty to read from stdin.
e.g. zypper on openSUSE.
Let's create this device node to unbreak those applications.
As /dev/tty is a synonym for the current controlling terminal
it cannot harm the host or any other containers.
Signed-off-by: Richard Weinberger <richard@nod.at>
libivrt lxc can only set generic weight for container,
This patch allows user to setup per device blkio
weigh for container.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
User namespaces will deny the ability to mount the SELinux
filesystem. This is harmless for libvirt's LXC needs, so the
error can be ignored.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Since these devices are created for the container.
the owner should be the root user of the container.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
container will create /dev/pts directory in /dev.
the owner of /dev should be the root user of container.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Since these tty devices will be used by container,
the owner of them should be the root user of container.
This patch also adds a new function virLXCControllerChown,
we can use this general function to change the owner of
files.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
user namespace doesn't allow to create devices in
uninit userns. We should create devices on host side.
We first mount tmpfs on dev directroy under state dir
of container. then create devices under this dev dir.
Finally in container, mount the dev directroy created
on host to the /dev/ directroy of container.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
This patch introduces new helper function
virLXCControllerSetupUserns, in this function,
we set the files uid_map and gid_map of the init
task of container.
lxcContainerSetID is used for creating cred for
tasks running in container. Since after setuid/setgid,
we may be a new user. This patch calls lxcContainerSetUserns
at first to make sure the new created files belong to
right user.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
User namespace will be enabled only when the idmap exist
in configuration.
If you want disable user namespace,just remove these
elements from XML.
If kernel doesn't support user namespace and idmap exist
in configuration file, libvirt lxc will start failed and
return "Kernel doesn't support user namespace" message.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
As a consequence of the cgroup layout changes from commit 'cfed9ad4', the
lxcDomainGetSchedulerParameters[Flags]()' and lxcGetSchedulerType() APIs
failed to return data for a non running domain. This can be seen through
a 'virsh schedinfo <domain>' command which returns:
Scheduler : Unknown
error: Requested operation is not valid: cgroup CPU controller is not mounted
Prior to that change a non running domain would return:
Scheduler : posix
cpu_shares : 0
vcpu_period : 0
vcpu_quota : 0
emulator_period: 0
emulator_quota : 0
This patch will restore the capability to return configuration only data
for a non running domain regardless of whether cgroups are available.