When there are two concurrent threads, we may dereference a NULL
pointer, even though it has been checked before:
1. Thread1: starts executing qemuDomainBlockStatsFlags() with nparams != 0.
It finds given disk and successfully pass check for disk->info.alias
not being NULL.
2. Thread2: starts executing qemuDomainDetachDeviceFlags() on the very same
disk as Thread1 is working on.
3. Thread1: gets to qemuDomainObjBeginJob() where it sets a job on a
domain.
4. Thread2: also tries to set a job. However, we are not guaranteed which
thread wins. So assume it's Thread2 who can continue.
5. Thread2: does the actual detach and frees disk->info.alias
6. Thread2: quits the job
7. Thread1: now successfully acquires the job, and accesses a NULL pointer.
Rename AppArmorSetImageFDLabel to AppArmorSetFDLabel which could
be used as a common function for *ALL* fd relabelling in Linux.
In apparmor profile for specific vm with uuid cdbebdfa-1d6d-65c3-be0f-fd74b978a773
Path: /etc/apparmor.d/libvirt/libvirt-cdbebdfa-1d6d-65c3-be0f-fd74b978a773.files
The last line is for the tapfd relabelling.
# DO NOT EDIT THIS FILE DIRECTLY. IT IS MANAGED BY LIBVIRT.
"/var/log/libvirt/**/rhel6qcow2.log" w,
"/var/lib/libvirt/**/rhel6qcow2.monitor" rw,
"/var/run/libvirt/**/rhel6qcow2.pid" rwk,
"/run/libvirt/**/rhel6qcow2.pid" rwk,
"/var/run/libvirt/**/*.tunnelmigrate.dest.rhel6qcow2" rw,
"/run/libvirt/**/*.tunnelmigrate.dest.rhel6qcow2" rw,
"/var/lib/libvirt/images/rhel6u3qcow2.img" rw,
"/dev/tap45" rw,
By using a loopback device, disks backed by plain files can
be made available to LXC containers. We make no attempt to
auto-detect format if <driver type="raw"/> is not set,
instead we unconditionally treat that as meaning raw. This
is to avoid the security issues inherent with format
auto-detection
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The current QEMU code for skipping log messages only skips over
'debug' message, switch to virLogProbablyLogMessage to make sure
it skips over all of them
Currently we rely on a VIR_ERROR message being logged by the
virRaiseError function to report LXC startup errors. This gives
the right message, but is rather ugly and can be truncated
if lots of log messages are written. Change the LXC controller
to explicitly print any virErrorPtr message to stderr. Then
change the driver to skip over anything that looks like a log
message.
The result is that this
error: Failed to start domain busy
error: internal error guest failed to start: 2013-03-04 19:46:42.846+0000: 1734: info : libvirt version: 1.0.2
2013-03-04 19:46:42.846+0000: 1734: error : virFileLoopDeviceAssociate:600 : Unable to open /root/disk.raw: No such file or directory
changes to
error: Failed to start domain busy
error: internal error guest failed to start: Unable to open /root/disk.raw: No such file or directory
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When reading log output from QEMU/LXC we need to skip over any
libvirt log messages. Currently the QEMU driver checks for a
fixed string, but this is better done with a regex. Add a method
virLogProbablyLogMessage to do a regex check
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
In the LXC container startup code when switching stdio
streams, we call VIR_FORCE_CLOSE on all FDs. This triggers
a huge number of warnings, but we don't see them because
stdio is closed at this point. strace() however shows them
which can confuse people debugging the code. Switch to
VIR_MASS_CLOSE to avoid this
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virNetDevSetupControlFull function was protected by a
conditional on SIOCBRADDBR, which is bogus since it does
not use that symbol. Update the conditionals around all
callers to do stricter checks to ensure we always build
succesfully
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The RHEL4 vintage header files do not define GET_VLAN_VID_CMD.
Conditionally define it in our source, since the kernel can
raise a runtime error if it isn't supported
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The loop.h on RHEL4 is broken and cannot be imported. We already
detect this in configure as a side-effect of looking for whether
LO_FLAGS_AUTOCLEAR is available. We protected the impl with
HAVE_DECL_LO_FLAGS_AUTOCLEAR, but not the header import
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
To avoid a clash with daemon() libc API, rename the
'daemon' param in the header file to 'binary'. The
source file already uses the name 'binary'.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
On RHEL-4 vintage one of the header files is polluted causing a
clash between the clone() syscall and the 'clone' parameter in
a libvirt driver API
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Commit 0df3e89 only touched the header, but the .c file had the
same shadowing potential.
* src/util/viralloc.c (virDeleteElementsN): s/remove/toremove/ to
match the header.
Code that validates the whitelist for the RNG device filename
didn't account for fact that filename may be NULL. This led
to a NULL reference crash. This wasn't caught since the test
suite was not covering this XML syntax
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Resolves the following valgrind error from qemuxml2argvtest:
==20393== 5 bytes in 1 blocks are definitely lost in loss record 2 of 60
==20393== at 0x4A0883C: malloc (vg_replace_malloc.c:270)
==20393== by 0x38D690A167: __vasprintf_chk (in /usr/lib64/libc-2.16.so)
==20393== by 0x4CB0D97: virVasprintf (stdio2.h:210)
==20393== by 0x4CB0E53: virAsprintf (virutil.c:2017)
==20393== by 0x428DC5: qemuAssignDeviceAliases (qemu_command.c:791)
==20393== by 0x41DF93: testCompareXMLToArgvHelper (qemuxml2argvtest.c:151)
==20393== by 0x41F53F: virtTestRun (testutils.c:157)
==20393== by 0x41DA9B: mymain (qemuxml2argvtest.c:885)
==20393== by 0x41FB7A: virtTestMain (testutils.c:719)
==20393== by 0x38D6821A04: (below main) (in /usr/lib64/libc-2.16.so)
==20393==
From qemu_command.c/line 791:
if (def->rng) {
if (virAsprintf(&def->rng->info.alias, "rng%d", 0) < 0)
goto no_memory;
}
This patch plugs two memory leaks, removes some useless and confusing
constructs and renames renames "cleanup" label as "error" since it is
only used for error path rather then being common for both success and
error paths.
1. The virObjectLock() call was unconditional, but Unlock was conditional
on vm being valid. Removed the check
2. A call to virDomainEventNewFromObj() isn't guaranteed to return an
event - that check needs to be made prior to libxlDomainEventQueue()
of the event. Did not add libxlDriverLock/Unlock around the call since
some callers already have lock taken
3. Need to initialize fd = -1 in libxlDoDomainSave() since we can jump
to cleanup before it's set.
4. Missing break;'s in libxlDomainModifyDeviceFlags() for case
LIBXL_DEVICE_UPDATE. The default: case would report an error
A value which is equal to a integer maximum such as LLONG_MAX is
a valid integer value.
The patch fix the following error:
1, virsh memtune vm --swap-hard-limit -1
2, virsh start vm
In debug mode, it shows error like:
virScaleInteger:1813 : numerical overflow:\
value too large: 9007199254740991KiB
This patch adds proper error reporting if parsing of cputune parameters
fails due to incorrect values provided by the user. Previously no errors
were reported in such a case and the failure was silently ignored.
Make the iterator function usable in the next patches. Also refactor
some parts to avoid strcmp if not necessary.
This commit tweaks and shadows the change that was done in commit
babe7dada0 and was needed after the
support for multiple console devices was added. Historically the first
<console> element is alias for the <serial> device.
There is some controversy[1] on the qemu list on whether qemu should
have ever allowed arbitrary file name passthrough, or whether it
should be restricted to JUST /dev/random and /dev/hwrng. It is
always easier to add support for additional filenames than it is
to remove support for something once released, so this patch
restricts libvirt 1.0.3 (where the virtio-random backend was first
supported) to just the two uncontroversial names, letting us defer
to a later date any decision on whether supporting arbitrary files
makes sense. Additionally, since qemu 1.4 does NOT support
/dev/fdset/nnn fd passthrough for the backend, limiting to just
two known names means that we don't get tempted to try fd
passthrough where it won't work.
[1]https://lists.gnu.org/archive/html/qemu-devel/2013-03/threads.html#00023
* src/conf/domain_conf.c (virDomainRNGDefParseXML): Only allow
/dev/random and /dev/hwrng.
* docs/schemas/domaincommon.rng: Flag invalid files.
* docs/formatdomain.html.in (elementsRng): Document this.
* tests/qemuxml2argvdata/qemuxml2argv-virtio-rng-random.args:
Update test to match.
* tests/qemuxml2argvdata/qemuxml2argv-virtio-rng-random.xml:
Likewise.
19c6ad9a (qemu: Refactor qemuDomainSetMemoryParameters) introduced
a new macro, VIR_GET_LIMIT_PARAMETER(PARAM, VALUE). But if statement
in the macro is not correct and so set_XXXX flags are set to false
in the wrong. As a result, libvirt ignores all memtune parameters.
This patch fixes the conditional expression to work correctly.
Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
BZ:https://bugzilla.redhat.com/show_bug.cgi?id=912021
Without error handler set, virDefaultErrorFunc will be called, the
error message is prefixed with "libvir:". It become a little better
by using prefix "libvirt:" when working with upper application.
For example:
1, stop libvirtd daemon
2, run virt-top.
libvir: XML-RPC error : Failed to connect \
socket to '/var/run/libvirt/libvirt-sock-ro': \
No such file or directory
libvirt: VIR_ERR_SYSTEM_ERROR: VIR_FROM_RPC: \
Failed to connect socket to '/var/run/libvirt/libvirt-sock-ro': \
No such file or directory
Commit f506a4c1 changed virSetUIDGID() to be a noop
when uid/gid are -1, while it used to be a noop when
they are <= 0.
The changes in this commit broke creating new VMs in GNOME Boxes
as qemuDomainCheckDiskPresence gets called during domain creation/startup,
which in turn calls virFileAccessibleAs which fails after calling
virSetUIDGID(0, 0) (Boxes uses session libvirtd). virSetUIDGID is called with
(0, 0) as these are the default user/group values in virQEMUDriverConfig
for session libvirtd.
This commit changes virQEMUDriverConfigNew to use -1 as the unpriviledged
uid/gid. I've also looked at the various places where cfg->user is used,
and they all seem to handle -1 correctly.
Currently, after we removed the qemu driver lock, it may happen
that two or more threads will start up a machine with macvlan and
race over virNetDevMacVLanCreateWithVPortProfile(). However,
there's a racy section in which we are generating a sequence of
possible device names and detecting if they exits. If we found
one which doesn't we try to create a device with that name.
However, the other thread is doing just the same. Assume it will
succeed and we must therefore fail. If this happens more than 5
times (which in massive parallel startup surely will) we return
-1 without any error reported. This patch is a simple hack to
both of these problems. It introduces a mutex, so only one thread
will enter the section, and if it runs out of possibilities,
error is reported. Moreover, the number of retries is raised to 20.
This reverts the hack done in
commit 568a6cda27
Author: Jiri Denemark <jdenemar@redhat.com>
Date: Fri Feb 15 15:11:47 2013 +0100
qemu: Avoid deadlock in autodestroy
since we now have a fix which avoids the deadlock scenario
entirely
There is a lock ordering problem in the QEMU close callback
APIs.
When starting a guest we have a lock on the VM. We then
set a autodestroy callback, which acquires a lock on the
close callbacks.
When running auto-destroy, we obtain a lock on the close
callbacks, then run each callbacks - which obtains a lock
on the VM.
This causes deadlock if anyone tries to start a VM, while
autodestroy is taking place.
The fix is to do autodestroy in 2 phases. First obtain
all the callbacks and remove them from the list under
the close callback lock. Then invoke each callback
from outside the close callback lock.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When the auto-destroy callback runs it is supposed to return
NULL if the virDomainObjPtr is no longer valid. It was not
doing this for transient guests, so we tried to virObjectUnlock
a mutex which had been freed. This often led to a crash.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
qemuProcessStart expects to be run with a job already set and every
caller except for qemuMigrationPrepareAny use it correctly. This bug can
be observed in libvirtd logs during incoming migration as
warning : qemuDomainObjEnterMonitorInternal:979 : This thread seems
to be the async job owner; entering monitor without asking for a
nested job is dangerous
With the apparmor security driver enabled, qemu instances fail
to start
# grep ^security_driver /etc/libvirt/qemu.conf
security_driver = "apparmor"
# virsh start test-kvm
error: Failed to start domain test-kvm
error: internal error security label already defined for VM
The model field of virSecurityLabelDef object is always populated
by virDomainDefGetSecurityLabelDef(), so remove the check for a
NULL model when verifying if a label is already defined for the
instance.
Checking for a NULL model and populating it later in
AppArmorGenSecurityLabel() has been left in the code to be
consistent with virSecuritySELinuxGenSecurityLabel().
As pointed out in
https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1034661
The sentence
"The function of PCI device addresses must less than 8"
does not quite make sense. Update that to read
"The function of PCI device addresses must be less than 8"
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Currently, qemuDomainShutdownFlags() chooses the agent method of
shutdown whenever the agent is configured. However, this
assumption is not enough as the guest agent may be unresponsive
at the moment. So unless guest agent method has been explicitly
requested, we should fall back to the ACPI method.
The unitialized local variable qemuVersion can cause an random value
to be returned for the hypervisor version, observable with virsh version.
Introduced by commit b46f7f4a0b
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
disk->src is still used for disks->hosts->name, do not free it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The QEMU driver has a list of devices nodes that are whitelisted
for all guests. The kernel has recently started returning an
error if you try to whitelist a device which does not exist.
This causes a warning in libvirt logs and an audit error for
any missing devices. eg
2013-02-27 16:08:26.515+0000: 29625: warning : virDomainAuditCgroup:451 : success=no virt=kvm resrc=cgroup reason=allow vm="vm031714" uuid=9d8f1de0-44f4-a0b1-7d50-e41ee6cd897b cgroup="/sys/fs/cgroup/devices/libvirt/qemu/vm031714/" class=path path=/dev/kqemu rdev=? acl=rw
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The code for putting the emulator threads in a separate cgroup
would spam the logs with warnings
2013-02-27 16:08:26.731+0000: 29624: warning : virCgroupMoveTask:887 : no vm cgroup in controller 3
2013-02-27 16:08:26.731+0000: 29624: warning : virCgroupMoveTask:887 : no vm cgroup in controller 4
2013-02-27 16:08:26.732+0000: 29624: warning : virCgroupMoveTask:887 : no vm cgroup in controller 6
This is because it has only created child cgroups for 3 of the
controllers, but was trying to move the processes from all the
controllers. The fix is to only try to move threads in the
controllers we actually created. Also remove the warning and
make it return a hard error to avoid such lazy callers in the
future.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virQEMUCloseCallbacksRunOne method was passing a uuid string
to virDomainObjListFindByUUID, when it actually expected to get
a raw uuid buffer. This was not caught by the compiler because
the method was using a 'void *uuid' instead of first casting
it to the expected type.
This regression was accidentally caused by refactoring in
commit 568a6cda27
Author: Jiri Denemark <jdenemar@redhat.com>
Date: Fri Feb 15 15:11:47 2013 +0100
qemu: Avoid deadlock in autodestroy
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=896092 mentions that
qemu 1.4 and earlier only accept a simple start-stop range for
the cpu=... argument of -numa. Libvirt would attempt to use
-numa cpu=1,3 for a disjoint range, which did not work as intended.
Upstream qemu will be adding a new syntax for disjoint cpu ranges
in 1.5; but the design for that syntax is still under discussion
at the time of this patch. So for libvirt 1.0.3, it is safest to
just reject attempts to build an invalid qemu command line; in the
future, we can add a capability bit and translate to the final
accepted design for selecting a disjoint cpu range in numa.
* src/qemu/qemu_command.c (qemuBuildNumaArgStr): Reject disjoint
ranges.
This reverts commit 383ebc4694.
We decided the xml for this feature needed more thought to make sure
we are doing it the best way, in particular wrt option values that
have multiple items.
