This eliminates the warning message reported in:
https://bugzilla.redhat.com/show_bug.cgi?id=624447
It was caused by a failure to open an image file that is not
accessible by root (the uid libvirtd is running as) because it's on a
root-squash NFS share, owned by a different user, with permissions of
660 (or maybe 600).
The solution is to use virFileOpenAs() rather than open(). The
codepath that generates the error is during qemuSetupDiskCGroup(), but
the actual open() is in a lower-level generic function called from
many places (virDomainDiskDefForeachPath), so some other pieces of the
code were touched just to add dummy (or possibly useful) uid and gid
arguments.
Eliminating this warning message has the nice side effect that the
requested operation may even succeed (which in this case isn't
necessary, but shouldn't hurt anything either).
Curently security labels can be of type 'dynamic' or 'static'.
If no security label is given, then 'dynamic' is assumed. The
current code takes advantage of this default, and avoids even
saving <seclabel> elements with type='dynamic' to disk. This
means if you temporarily change security driver, the guests
can all still start.
With the introduction of sVirt to LXC though, there needs to be
a new default of 'none' to allow unconfined LXC containers.
This patch introduces two new security label types
- default: the host configuration decides whether to run the
guest with type 'none' or 'dynamic' at guest start
- none: the guest will run unconfined by security policy
The 'none' label type will obviously be undesirable for some
deployments, so a new qemu.conf option allows a host admin to
mandate confined guests. It is also possible to turn off default
confinement
security_default_confined = 1|0 (default == 1)
security_require_confined = 1|0 (default == 0)
* src/conf/domain_conf.c, src/conf/domain_conf.h: Add new
seclabel types
* src/security/security_manager.c, src/security/security_manager.h:
Set default sec label types
* src/security/security_selinux.c: Handle 'none' seclabel type
* src/qemu/qemu.conf, src/qemu/qemu_conf.c, src/qemu/qemu_conf.h,
src/qemu/libvirtd_qemu.aug: New security config options
* src/qemu/qemu_driver.c: Tell security driver about default
config
The old virRandom() API was not generating good random numbers.
Replace it with a new API virRandomBits which instead of being
told the upper limit, gets told the number of bits of randomness
required.
* src/util/virrandom.c, src/util/virrandom.h: Add virRandomBits,
and move virRandomInitialize
* src/util/util.h, src/util/util.c: Delete virRandom and
virRandomInitialize
* src/libvirt.c, src/security/security_selinux.c,
src/test/test_driver.c, src/util/iohelper.c: Update for
changes from virRandom to virRandomBits
* src/storage/storage_backend_iscsi.c: Remove bogus call
to virRandomInitialize & convert to virRandomBits
When sVirt is integrated with the LXC driver, it will be neccessary
to invoke the security driver APIs using only a virDomainDefPtr
since the lxc_container.c code has no virDomainObjPtr available.
Aside from two functions which want obj->pid, every bit of the
security driver code only touches obj->def. So we don't need to
pass a virDomainObjPtr into the security drivers, a virDomainDefPtr
is sufficient. Two functions also gain a 'pid_t pid' argument.
* src/qemu/qemu_driver.c, src/qemu/qemu_hotplug.c,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c,
src/security/security_dac.c,
src/security/security_driver.h,
src/security/security_manager.c,
src/security/security_manager.h,
src/security/security_nop.c,
src/security/security_selinux.c,
src/security/security_stack.c: Change all security APIs to use a
virDomainDefPtr instead of virDomainObjPtr
This wires up the XML changes in the previous patch to let SELinux
labeling honor user overrides, as well as affecting the live XML
configuration in one case where the user didn't specify anything
in the offline XML.
I noticed that the logs contained messages like this:
2011-12-05 23:32:40.382+0000: 26569: warning : SELinuxRestoreSecurityFileLabel:533 : cannot lookup default selinux label for /nfs/libvirt/images/dom.img
for all my domain images living on NFS. But if we would just remember
that on domain creation that we were unable to set a SELinux label (due to
NFSv3 lacking labels, or NFSv4 not being configured to expose attributes),
then we could avoid wasting the time trying to clear the label on
domain shutdown. This in turn is one less point of NFS failure,
especially since there have been documented cases of virDomainDestroy
hanging during an attempted operation on a failed NFS connection.
* src/security/security_selinux.c (SELinuxSetFilecon): Move guts...
(SELinuxSetFileconHelper): ...to new function.
(SELinuxSetFileconOptional): New function.
(SELinuxSetSecurityFileLabel): Honor override label, and remember
if labeling failed.
(SELinuxRestoreSecurityImageLabelInt): Skip relabeling based on
override.
Network disks don't have paths to be resolved or files to be checked
for ownership. ee3efc41e6 checked this
for some image label functions, but was partially reverted in a
refactor. This finishes adding the check to each security driver's
set and restore label methods for images.
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
While Xen only has a single paravirt console, UML, and
QEMU both support multiple paravirt consoles. The LXC
driver can also be trivially made to support multiple
consoles. This patch extends the XML to allow multiple
<console> elements in the XML. It also makes the UML
and QEMU drivers support this config.
* src/conf/domain_conf.c, src/conf/domain_conf.h: Allow
multiple <console> devices
* src/lxc/lxc_driver.c, src/xen/xen_driver.c,
src/xenxs/xen_sxpr.c, src/xenxs/xen_xm.c: Update for
internal API changes
* src/security/security_selinux.c, src/security/virt-aa-helper.c:
Only label consoles that aren't a copy of the serial device
* src/qemu/qemu_command.c, src/qemu/qemu_driver.c,
src/qemu/qemu_process.c, src/uml/uml_conf.c,
src/uml/uml_driver.c: Support multiple console devices
* tests/qemuxml2xmltest.c, tests/qemuxml2argvtest.c: Extra
tests for multiple virtio consoles. Set QEMU_CAPS_CHARDEV
for all console /channel tests
* tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-auto.args,
tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
tests/qemuxml2argvdata/qemuxml2argv-console-virtio.args: Update
for correct chardev syntax
* tests/qemuxml2argvdata/qemuxml2argv-console-virtio-many.args,
tests/qemuxml2argvdata/qemuxml2argv-console-virtio-many.xml: New
test file
This patch fixes the regression with using named pipes for qemu serial
devices noted in:
https://bugzilla.redhat.com/show_bug.cgi?id=740478
The problem was that, while new code in libvirt looks for a single
bidirectional fifo of the name given in the config, then relabels that
and continues without looking for / relabelling the two unidirectional
fifos named ${name}.in and ${name}.out, qemu looks in the opposite
order. So if the user had naively created all three fifos, libvirt
would relabel the bidirectional fifo to allow qemu access, but qemu
would attempt to use the two unidirectional fifos and fail (because it
didn't have proper permissions/rights).
This patch changes the order that libvirt looks for the fifos to match
what qemu does - first it looks for the dual fifos, then it looks for
the single bidirectional fifo. If it finds the dual unidirectional
fifos first, it labels/chowns them and ignores any possible
bidirectional fifo.
(Note commit d37c6a3a (which first appeared in libvirt-0.9.2) added
the code that checked for a bidirectional fifo. Prior to that commit,
bidirectional fifos for serial devices didn't work because libvirt
always required the ${name}.(in|out) fifos to exist, and qemu would
always prefer those.
The virSecurityManagerSetProcessFDLabel method was introduced
after a mis-understanding from a conversation about SELinux
socket labelling. The virSecurityManagerSetSocketLabel method
should have been used for all such scenarios.
* src/security/security_apparmor.c, src/security/security_apparmor.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: Remove SetProcessFDLabel driver
This API labels all sockets created until ClearSocketLabel is called in
a way that a vm can access them (i.e., they are labeled with svirt_t
based label in SELinux).
The APIs are designed to label a socket in a way that the libvirt daemon
itself is able to access it (i.e., in SELinux the label is virtd_t based
as opposed to svirt_* we use for labeling resources that need to be
accessed by a vm). The new name reflects this.
When no <seclabel> is present in the XML, the virDomainSeclabelDef
struct is left as all zeros. Unfortunately, this means it gets setup
as type=dynamic, with relabel=no, which is an illegal combination.
Change the 'bool relabel' attribute in virDomainSeclabelDef to
the inverse 'bool norelabel' so that the default initialization
is sensible
* src/conf/domain_conf.c, src/conf/domain_conf.h,
src/security/security_apparmor.c, src/security/security_selinux.c:
Replace 'relabel' with 'norelabel'
Add a new attribute to the <seclabel> XML to allow resource
relabelling to be enabled with static label usage.
<seclabel model='selinux' type='static' relabel='yes'>
<label>system_u:system_r:svirt_t:s0:c392,c662</label>
</seclabel>
* docs/schemas/domain.rng: Add relabel attribute
* src/conf/domain_conf.c, src/conf/domain_conf.h: Parse
the 'relabel' attribute
* src/qemu/qemu_process.c: Unconditionally clear out the
'imagelabel' attribute
* src/security/security_apparmor.c: Skip based on 'relabel'
attribute instead of label type
* src/security/security_selinux.c: Skip based on 'relabel'
attribute instead of label type and fill in <imagelabel>
attribute if relabel is enabled.
Normally the dynamic labelling mode will always use a base
label of 'svirt_t' for VMs. Introduce a <baselabel> field
in the <seclabel> XML to allow this base label to be changed
eg
<seclabel type='dynamic' model='selinux'>
<baselabel>system_u:object_r:virt_t:s0</baselabel>
</seclabel>
* docs/schemas/domain.rng: Add <baselabel>
* src/conf/domain_conf.c, src/conf/domain_conf.h: Parsing
of base label
* src/qemu/qemu_process.c: Don't reset 'model' attribute if
a base label is specified
* src/security/security_apparmor.c: Refuse to support base label
* src/security/security_selinux.c: Use 'baselabel' when generating
label, if available
Add a new security driver method for labelling an FD with
the process label, rather than the image label
* src/libvirt_private.syms, src/security/security_apparmor.c,
src/security/security_dac.c, src/security/security_driver.h,
src/security/security_manager.c, src/security/security_manager.h,
src/security/security_selinux.c, src/security/security_stack.c:
Add virSecurityManagerSetProcessFDLabel & impl
The virSecurityManagerSetFDLabel method is used to label
file descriptors associated with disk images. There will
shortly be a need to label other file descriptors in a
different way. So the current name is ambiguous. Rename
the method to virSecurityManagerSetImageFDLabel to clarify
its purpose
* src/libvirt_private.syms,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c, src/security/security_dac.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: s/FDLabel/ImageFDLabel/
When setting up a FIFO for QEMU, it allows either a pair
of fifos used unidirectionally, or a single fifo used
bidirectionally. Look for the bidirectional fifo first
when labelling since that is more useful
* src/security/security_dac.c,
src/security/security_selinux.c: Fix fifo handling
Even with -Wuninitialized (which is part of autobuild.sh
--enable-compile-warnings=error), gcc does NOT catch this
use of an uninitialized variable:
{
if (cond)
goto error;
int a = 1;
error:
printf("%d", a);
}
which prints 0 (supposing the stack started life wiped) if
cond was true. Clang will catch it, but we don't use clang
as often. Using gcc -Wjump-misses-init catches it, but also
gives false positives:
{
if (cond)
goto error;
int a = 1;
return a;
error:
return 0;
}
Here, a was never used in the scope of the error block, so
declaring it after goto is technically fine (and clang agrees).
However, given that our HACKING already documents a preference
to C89 decl-before-statement, the false positive warning is
enough of a prod to comply with HACKING.
[Personally, I'd _really_ rather use C99 decl-after-statement
to minimize scope, but until gcc can efficiently and reliably
catch scoping and uninitialized usage bugs, I'll settle with
the compromise of enforcing a coding standard that happens to
reject false positives if it can also detect real bugs.]
* acinclude.m4 (LIBVIRT_COMPILE_WARNINGS): Add -Wjump-misses-init.
* src/util/util.c (__virExec): Adjust offenders.
* src/conf/domain_conf.c (virDomainTimerDefParseXML): Likewise.
* src/remote/remote_driver.c (doRemoteOpen): Likewise.
* src/phyp/phyp_driver.c (phypGetLparNAME, phypGetLparProfile)
(phypGetVIOSFreeSCSIAdapter, phypVolumeGetKey)
(phypGetStoragePoolDevice)
(phypVolumeGetPhysicalVolumeByStoragePool)
(phypVolumeGetPath): Likewise.
* src/vbox/vbox_tmpl.c (vboxNetworkUndefineDestroy)
(vboxNetworkCreate, vboxNetworkDumpXML)
(vboxNetworkDefineCreateXML): Likewise.
* src/xenapi/xenapi_driver.c (getCapsObject)
(xenapiDomainDumpXML): Likewise.
* src/xenapi/xenapi_utils.c (createVMRecordFromXml): Likewise.
* src/security/security_selinux.c (SELinuxGenNewContext):
Likewise.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia):
Likewise.
* src/qemu/qemu_process.c (qemuProcessWaitForMonitor): Likewise.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextGetPtyPaths):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainShutdown)
(qemudDomainBlockStats, qemudDomainMemoryPeek): Likewise.
* src/storage/storage_backend_iscsi.c
(virStorageBackendCreateIfaceIQN): Likewise.
* src/node_device/node_device_udev.c (udevProcessPCI): Likewise.
A need was found to set the SELinux context label on an open fd (a
pipe, as a matter of fact). This patch adds a function to the security
driver API that will set the label on an open fd to secdef.label. For
all drivers other than the SELinux driver, it's a NOP. For the SElinux
driver, it calls fsetfilecon().
If the return is a failure, it only returns error up to the caller if
1) the desired label is different from the existing label, 2) the
destination fd is of a type that supports setting the selinux context,
and 3) selinux is in enforcing mode. Otherwise it will return
success. This follows the pattern of the existing function
SELinuxSetFilecon().
The current security driver usage requires horrible code like
if (driver->securityDriver &&
driver->securityDriver->domainSetSecurityHostdevLabel &&
driver->securityDriver->domainSetSecurityHostdevLabel(driver->securityDriver,
vm, hostdev) < 0)
This pair of checks for NULL clutters up the code, making the driver
calls 2 lines longer than they really need to be. The goal of the
patchset is to change the calling convention to simply
if (virSecurityManagerSetHostdevLabel(driver->securityDriver,
vm, hostdev) < 0)
The first check for 'driver->securityDriver' being NULL is removed
by introducing a 'no op' security driver that will always be present
if no real driver is enabled. This guarentees driver->securityDriver
!= NULL.
The second check for 'driver->securityDriver->domainSetSecurityHostdevLabel'
being non-NULL is hidden in a new abstraction called virSecurityManager.
This separates the driver callbacks, from main internal API. The addition
of a virSecurityManager object, that is separate from the virSecurityDriver
struct also allows for security drivers to carry state / configuration
information directly. Thus the DAC/Stack drivers from src/qemu which
used to pull config from 'struct qemud_driver' can now be moved into
the 'src/security' directory and store their config directly.
* src/qemu/qemu_conf.h, src/qemu/qemu_driver.c: Update to
use new virSecurityManager APIs
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_dac.h
src/qemu/qemu_security_stacked.c, src/qemu/qemu_security_stacked.h:
Move into src/security directory
* src/security/security_stack.c, src/security/security_stack.h,
src/security/security_dac.c, src/security/security_dac.h: Generic
versions of previous QEMU specific drivers
* src/security/security_apparmor.c, src/security/security_apparmor.h,
src/security/security_driver.c, src/security/security_driver.h,
src/security/security_selinux.c, src/security/security_selinux.h:
Update to take virSecurityManagerPtr object as the first param
in all callbacks
* src/security/security_nop.c, src/security/security_nop.h: Stub
implementation of all security driver APIs.
* src/security/security_manager.h, src/security/security_manager.c:
New internal API for invoking security drivers
* src/libvirt.c: Add missing debug for security APIs
Network disks are accessed by qemu directly, and have no
associated file on the host, so checking for file ownership etc.
is unnecessary.
Signed-off-by: Josh Durgin <joshd@hq.newdream.net>
* configure.ac (with_selinux): Check for <selinux/label.h>.
* src/security/security_selinux.c (getContext): New function.
(SELinuxRestoreSecurityFileLabel): Use it to restore compilation
when using older libselinux.
security_context_t happens to be a typedef for char*, and happens to
begin with a string usable as a raw context string. But in reality,
it is an opaque type that may or may not have additional information
after the first NUL byte, where that additional information can
include pointers that can only be freed via freecon().
Proof is from this valgrind run of daemon/libvirtd:
==6028== 839,169 (40 direct, 839,129 indirect) bytes in 1 blocks are definitely lost in loss record 274 of 274
==6028== at 0x4A0515D: malloc (vg_replace_malloc.c:195)
==6028== by 0x3022E0D48C: selabel_open (label.c:165)
==6028== by 0x3022E11646: matchpathcon_init_prefix (matchpathcon.c:296)
==6028== by 0x3022E1190D: matchpathcon (matchpathcon.c:317)
==6028== by 0x4F9D842: SELinuxRestoreSecurityFileLabel (security_selinux.c:382)
800k is a lot of memory to be leaking.
* src/storage/storage_backend.c
(virStorageBackendUpdateVolTargetInfoFD): Avoid leak on error.
* src/security/security_selinux.c
(SELinuxReserveSecurityLabel, SELinuxGetSecurityProcessLabel)
(SELinuxRestoreSecurityFileLabel): Use correct function to free
security_context_t.
The code in SELinuxRestoreSecurityChardevLabel() was trying to
use SELinuxSetFilecon directly for devices or file types while
it should really use SELinuxRestoreSecurityFileLabel encapsulating
routine, which avoid various problems like resolving symlinks,
making sure he file exists and work around NFS problems
If virDomainAttachDevice() was called with an image that was located
on a root-squashed NFS server, and in a directory that was unreadable
by root on the machine running libvirtd, the attach would fail due to
an attempt to change the selinux label of the image with EACCES (which
isn't covered as an ignore case in SELinuxSetFilecon())
NFS doesn't support SELinux labelling anyway, so we mimic the failure
handling of commit 93a18bbafa, which
just ignores the errors if the target is on an NFS filesystem (in
SELinuxSetSecurityAllLabel() only, though.)
This can be seen as a follow-on to commit
347d266c51, which ignores file open
failures of files on NFS that occur directly in
virDomainDiskDefForeachPath() (also necessary), but does not ignore
failures in functions that are called from there (eg
SELinuxSetSecurityFileLabel()).
Using automated replacement with sed and editing I have now replaced all
occurrences of close() with VIR_(FORCE_)CLOSE() except for one, of
course. Some replacements were straight forward, others I needed to pay
attention. I hope I payed attention in all the right places... Please
have a look. This should have at least solved one more double-close
error.
NFS in root squash mode may prevent opening disk images to
determine backing store. Ignore errors in this scenario.
* src/security/security_selinux.c: Ignore open failures on disk
images
NFS does not support file labelling, so ignore this error
for stdin_path when on NFS.
* src/security/security_selinux.c: Ignore failures on labelling
stdin_path on NFS
* src/util/storage_file.c, src/util/storage_file.h: Refine
virStorageFileIsSharedFS() to allow it to check for a
specific FS type.
A more natural auditing point would perhaps be
SELinuxSetSecurityProcessLabel, but this happens in the child after root
permissions are dropped, so the kernel would refuse the audit record.
Disk format probing is now disabled by default. A new config
option in /etc/qemu/qemu.conf will re-enable it for existing
deployments where this causes trouble
The implementation of security driver callbacks often needs
to access the security driver object. Currently only a handful
of callbacks include the driver object as a parameter. Later
patches require this is many more places.
* src/qemu/qemu_driver.c: Pass in the security driver object
to all callbacks
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_stacked.c,
src/security/security_apparmor.c, src/security/security_driver.h,
src/security/security_selinux.c: Add a virSecurityDriverPtr
param to all security callbacks
Update the QEMU cgroups code, QEMU DAC security driver, SELinux
and AppArmour security drivers over to use the shared helper API
virDomainDiskDefForeachPath().
* src/qemu/qemu_driver.c, src/qemu/qemu_security_dac.c,
src/security/security_selinux.c, src/security/virt-aa-helper.c:
Convert over to use virDomainDiskDefForeachPath()
Require the disk image to be passed into virStorageFileGetMetadata.
If this is set to VIR_STORAGE_FILE_AUTO, then the format will be
resolved using probing. This makes it easier to control when
probing will be used
* src/qemu/qemu_driver.c, src/qemu/qemu_security_dac.c,
src/security/security_selinux.c, src/security/virt-aa-helper.c:
Set VIR_STORAGE_FILE_AUTO when calling virStorageFileGetMetadata.
* src/storage/storage_backend_fs.c: Probe for disk format before
calling virStorageFileGetMetadata.
* src/util/storage_file.h, src/util/storage_file.c: Remove format
from virStorageFileMeta struct & require it to be passed into
method.
Also restore the label to its original value after qemu is finished
with the file.
Prior to this patch, qemu domain restore did not function properly if
selinux was set to enforce.
When configuring serial, parallel, console or channel devices
with a file, dev or pipe backend type, it is necessary to label
the file path in the security drivers. For char devices of type
file, it is neccessary to pre-create (touch) the file if it does
not already exist since QEMU won't be allowed todo so itself.
dev/pipe configs already require the admin to pre-create before
starting the guest.
* src/qemu/qemu_security_dac.c: set file ownership for character
devices
* src/security/security_selinux.c: Set file labeling for character
devices
* src/qemu/qemu_driver.c: Add character devices to cgroup ACL
The restore code is done in places where errors cannot be
raised, since they will overwrite over pre-existing errors.
* src/security/security_selinux.c: Only warn about failures
in label restore, don't report errors
When SELinux is running in MLS mode, libvirtd will have a
different security level to the VMs. For libvirtd to be
able to connect to the monitor console, the client end of
the UNIX domain socket needs a different label. This adds
infrastructure to set the socket label via the security
driver framework
* src/qemu/qemu_driver.c: Call out to socket label APIs in
security driver
* src/qemu/qemu_security_stacked.c: Wire up socket label
drivers
* src/security/security_driver.h: Define security driver
entry points for socket labelling
* src/security/security_selinux.c: Set socket label based on
VM label
Adjust args to qemudStartVMDaemon() to also specify path to stdin_fd,
so this can be passed to the AppArmor driver via SetSecurityAllLabel().
This updates all calls to qemudStartVMDaemon() as well as setting up
the non-AppArmor security driver *SetSecurityAllLabel() declarations
for the above. This is required for the following
"apparmor-fix-save-restore" patch since AppArmor resolves the passed
file descriptor to the pathname given to open().
Do not require each caller of virStorageFileGetMetadata and
virStorageFileGetMetadataFromFD to first clear the storage of the
"meta" buffer. Instead, initialize that storage in
virStorageFileGetMetadataFromFD.
* src/util/storage_file.c (virStorageFileGetMetadataFromFD): Clear
"meta" here, not before each of the following callers.
* src/qemu/qemu_driver.c (qemuSetupDiskCgroup): Don't clear "meta" here.
(qemuTeardownDiskCgroup): Likewise.
* src/qemu/qemu_security_dac.c (qemuSecurityDACSetSecurityImageLabel):
Likewise.
* src/security/security_selinux.c (SELinuxSetSecurityImageLabel):
Likewise.
* src/security/virt-aa-helper.c (get_files): Likewise.
virFileResolveLink was returning a positive value on error,
thus confusing callers that assumed failure was < 0. The
confusion is further evidenced by callers that would have
ended up calling virReportSystemError with a negative value
instead of a valid errno.
Fixes Red Hat BZ #591363.
* src/util/util.c (virFileResolveLink): Live up to documentation.
* src/qemu/qemu_security_dac.c
(qemuSecurityDACRestoreSecurityFileLabel): Adjust callers.
* src/security/security_selinux.c
(SELinuxRestoreSecurityFileLabel): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskDeleteVol): Likewise.
When QEMU runs with its disk on NFS, and as a non-root user, the
disk is chownd to that non-root user. When migration completes
the last step is shutting down the QEMU on the source host. THis
normally resets user/group/security label. This is bad when the
VM was just migrated because the file is still in use on the dest
host. It is thus neccessary to skip the reset step for any files
found to be on a shared filesystem
* src/libvirt_private.syms: Export virStorageFileIsSharedFS
* src/util/storage_file.c, src/util/storage_file.h: Add a new
method virStorageFileIsSharedFS() to determine if a file is
on a shared filesystem (NFS, GFS, OCFS2, etc)
* src/qemu/qemu_driver.c: Tell security driver not to reset
disk labels on migration completion
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_stacked.c,
src/security/security_selinux.c, src/security/security_driver.h,
src/security/security_apparmor.c: Add ability to skip disk
restore step for files on shared filesystems.
