Commit Graph

321 Commits

Author SHA1 Message Date
Eric Blake
16ac4c9d64 conf: move host disk type to util/
A continuation of the migration of disk details to virstoragefile.
This patch moves a single enum, but converting the name has quite
a bit of fallout.

* src/conf/domain_conf.h (virDomainDiskType): Move...
* src/util/virstoragefile.h (virStorageType): ...and rename.
* src/bhyve/bhyve_command.c (bhyveBuildDiskArgStr)
(virBhyveProcessBuildLoadCmd): Update clients.
* src/conf/domain_conf.c (virDomainDiskSourceDefParse)
(virDomainDiskDefParseXML, virDomainDiskSourceDefFormatInternal)
(virDomainDiskDefFormat, virDomainDiskGetActualType)
(virDomainDiskDefForeachPath, virDomainDiskSourceIsBlockType):
Likewise.
* src/conf/snapshot_conf.h (_virDomainSnapshotDiskDef): Likewise.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefParseXML)
(virDomainSnapshotAlignDisks, virDomainSnapshotDiskDefFormat):
Likewise.
* src/esx/esx_driver.c (esxAutodetectSCSIControllerModel)
(esxDomainDefineXML): Likewise.
* src/locking/domain_lock.c (virDomainLockManagerAddDisk):
Likewise.
* src/lxc/lxc_controller.c
(virLXCControllerSetupLoopDeviceDisk)
(virLXCControllerSetupNBDDeviceDisk)
(virLXCControllerSetupLoopDevices, virLXCControllerSetupDisk):
Likewise.
* src/parallels/parallels_driver.c (parallelsGetHddInfo):
Likewise.
* src/phyp/phyp_driver.c (phypDiskType): Likewise.
* src/qemu/qemu_command.c (qemuGetDriveSourceString)
(qemuDomainDiskGetSourceString, qemuBuildDriveStr)
(qemuBuildCommandLine, qemuParseCommandLineDisk)
(qemuParseCommandLine): Likewise.
* src/qemu/qemu_conf.c (qemuCheckSharedDevice)
(qemuTranslateDiskSourcePool)
(qemuTranslateSnapshotDiskSourcePool): Likewise.
* src/qemu/qemu_domain.c (qemuDomainDeviceDefPostParse)
(qemuDomainDetermineDiskChain): Likewise.
* src/qemu/qemu_driver.c (qemuDomainGetBlockInfo)
(qemuDomainSnapshotPrepareDiskExternalBackingInactive)
(qemuDomainSnapshotPrepareDiskExternalBackingActive)
(qemuDomainSnapshotPrepareDiskExternalOverlayActive)
(qemuDomainSnapshotPrepareDiskExternalOverlayInactive)
(qemuDomainSnapshotPrepareDiskInternal)
(qemuDomainSnapshotPrepare)
(qemuDomainSnapshotCreateSingleDiskActive): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia):
Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsSafe): Likewise.
* src/security/security_apparmor.c
(AppArmorRestoreSecurityImageLabel)
(AppArmorSetSecurityImageLabel): Likewise.
* src/security/security_dac.c (virSecurityDACSetSecurityImageLabel)
(virSecurityDACRestoreSecurityImageLabelInt)
(virSecurityDACSetSecurityAllLabel): Likewise.
* src/security/security_selinux.c
(virSecuritySELinuxRestoreSecurityImageLabelInt)
(virSecuritySELinuxSetSecurityImageLabel)
(virSecuritySELinuxSetSecurityAllLabel): Likewise.
* src/storage/storage_backend.c (virStorageFileBackendForType):
Likewise.
* src/storage/storage_backend_fs.c (virStorageFileBackendFile)
(virStorageFileBackendBlock): Likewise.
* src/storage/storage_backend_gluster.c
(virStorageFileBackendGluster): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainGetXMLDesc, vboxAttachDrives)
(vboxDomainAttachDeviceImpl, vboxDomainDetachDevice): Likewise.
* src/vmware/vmware_conf.c (vmwareVmxPath): Likewise.
* src/vmx/vmx.c (virVMXParseDisk, virVMXFormatDisk)
(virVMXFormatFloppy): Likewise.
* src/xenxs/xen_sxpr.c (xenParseSxprDisks, xenParseSxpr)
(xenFormatSxprDisk): Likewise.
* src/xenxs/xen_xm.c (xenParseXM, xenFormatXMDisk): Likewise.
* tests/securityselinuxlabeltest.c (testSELinuxLoadDef):
Likewise.
* src/libvirt_private.syms (domain_conf.h): Move symbols...
(virstoragefile.h): ...as appropriate.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-04-01 10:38:13 -06:00
Eric Blake
3e92938656 conf: split security label structs to util/
In order to reuse the newly-created host-side disk struct in
the virstoragefile backing chain code, I first have to move
it to util/.  This starts the process, by first moving the
security label structures.

* src/conf/domain_conf.h (virDomainDefGenSecurityLabelDef)
(virDomainDiskDefGenSecurityLabelDef, virSecurityLabelDefFree)
(virSecurityDeviceLabelDefFree, virSecurityLabelDef)
(virSecurityDeviceLabelDef): Move...
* src/util/virseclabel.h: ...to new file.
(virSecurityLabelDefNew, virSecurityDeviceLabelDefNew): Rename the
GenSecurity functions.
* src/qemu/qemu_process.c (qemuProcessAttach): Adjust callers.
* src/security/security_manager.c (virSecurityManagerGenLabel):
Likewise.
* src/security/security_selinux.c
(virSecuritySELinuxSetSecurityFileLabel): Likewise.
* src/util/virseclabel.c: New file.
* src/conf/domain_conf.c: Move security code, and fix fallout.
* src/Makefile.am (UTIL_SOURCES): Build new file.
* src/libvirt_private.syms (domain_conf.h): Move symbols...
(virseclabel.h): ...to new section.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-04-01 10:38:12 -06:00
Cédric Bosdonnat
74e86b6b25 Fix apparmor profile to make vfio pci passthrough work
See lp#1276719 for the bug description. As virt-aa-helper doesn't know
the VFIO groups to use for the guest, allow access to all
/dev/vfio/[0-9]* and /dev/vfio/vfio files if there is a potential need
for vfio

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-03-27 09:09:23 -06:00
Cédric Bosdonnat
0500fbd4b6 Fixed regression in apparmor profiles for qemu brought by 43c030f 2014-03-27 09:04:08 -06:00
Ján Tomko
9e7ecabf94 Indent top-level labels by one space in the rest of src/ 2014-03-25 14:58:40 +01:00
Peter Krempa
ccef7d7876 apparmor: Fix build after split of disk source metadata
Commit 4f20226664 breaks build with
AppArmor enabled as it missed the refactor to the new accessors.
2014-03-24 20:00:11 +01:00
Eric Blake
4f20226664 conf: prepare to track multiple host source files per <disk>
It's finally time to start tracking disk backing chains in
<domain> XML.  The first step is to start refactoring code
so that we have an object more convenient for representing
each host source resource in the context of a single guest
<disk>.  Ultimately, I plan to move the new type into src/util
where it can be reused by virStorageFile, but to make the
transition easier to review, this patch just creates the
new type then fixes everything until it compiles again.

* src/conf/domain_conf.h (_virDomainDiskDef): Split...
(_virDomainDiskSourceDef): ...to new struct.
(virDomainDiskAuthClear): Use new type.
* src/conf/domain_conf.c (virDomainDiskDefFree): Split...
(virDomainDiskSourceDefClear): ...to new function.
(virDomainDiskGetType, virDomainDiskSetType)
(virDomainDiskGetSource, virDomainDiskSetSource)
(virDomainDiskGetDriver, virDomainDiskSetDriver)
(virDomainDiskGetFormat, virDomainDiskSetFormat)
(virDomainDiskAuthClear, virDomainDiskGetActualType)
(virDomainDiskDefParseXML, virDomainDiskSourceDefFormat)
(virDomainDiskDefFormat, virDomainDiskDefForeachPath)
(virDomainDiskDefGetSecurityLabelDef)
(virDomainDiskSourceIsBlockType): Adjust all users.
* src/lxc/lxc_controller.c (virLXCControllerSetupDisk):
Likewise.
* src/lxc/lxc_driver.c (lxcDomainAttachDeviceMknodHelper):
Likewise.
* src/qemu/qemu_command.c (qemuAddRBDHost, qemuParseRBDString)
(qemuParseDriveURIString, qemuParseGlusterString)
(qemuParseISCSIString, qemuParseNBDString)
(qemuDomainDiskGetSourceString, qemuBuildDriveStr)
(qemuBuildCommandLine, qemuParseCommandLineDisk)
(qemuParseCommandLine): Likewise.
* src/qemu/qemu_conf.c (qemuCheckSharedDevice)
(qemuAddISCSIPoolSourceHost, qemuTranslateDiskSourcePool):
Likewise.
* src/qemu/qemu_driver.c (qemuDomainUpdateDeviceConfig)
(qemuDomainPrepareDiskChainElement)
(qemuDomainSnapshotCreateInactiveExternal)
(qemuDomainSnapshotPrepareDiskExternalBackingInactive)
(qemuDomainSnapshotPrepareDiskInternal)
(qemuDomainSnapshotPrepare)
(qemuDomainSnapshotCreateSingleDiskActive)
(qemuDomainSnapshotUndoSingleDiskActive)
(qemuDomainBlockPivot, qemuDomainBlockJobImpl)
(qemuDomainBlockCopy, qemuDomainBlockCommit): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsSafe): Likewise.
* src/qemu/qemu_process.c (qemuProcessGetVolumeQcowPassphrase)
(qemuProcessInitPasswords): Likewise.
* src/security/security_selinux.c
(virSecuritySELinuxSetSecurityFileLabel): Likewise.
* src/storage/storage_driver.c (virStorageFileInitFromDiskDef):
Likewise.
* tests/securityselinuxlabeltest.c (testSELinuxLoadDef):
Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-03-24 12:18:34 -06:00
Eric Blake
2aad0ebe2d conf: use disk source accessors in security/
Part of a series of cleanups to use new accessor methods.

* src/security/security_dac.c (virSecurityDACSetSecurityImageLabel)
(virSecurityDACRestoreSecurityImageLabelInt)
(virSecurityDACSetSecurityAllLabel): Use accessors.
* src/security/security_selinux.c
(virSecuritySELinuxRestoreSecurityImageLabelInt)
(virSecuritySELinuxSetSecurityImageLabel)
(virSecuritySELinuxSetSecurityAllLabel): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-03-24 11:59:50 -06:00
Martin Kletzander
95aed7febc Use K&R style for curly braces in remaining files
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-03-20 17:27:17 +01:00
Scott Sullivan
0099a4ae2b is_selinux_enabled() returns -1 on error, account for this.
Per the documentation, is_selinux_enabled() returns -1 on error.
Account for this. Previously when -1 was being returned the condition
would still be true. I was noticing this because on my system that has
selinux disabled I was getting this in the libvirt.log every 5
seconds:

error : virIdentityGetSystem:173 : Unable to lookup SELinux process context: Invalid argument

With this patch applied, I no longer get these messages every 5
seconds. I am submitting this in case its deemed useful for inclusion.
Anyone have any comments on this change? This is a patch off current
master.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-03-20 16:26:55 +01:00
Daniel P. Berrange
2835c1e730 Add virLogSource variables to all source files
Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-03-18 14:29:22 +00:00
Martin Kletzander
14fc041f69 Don't leave empty first line in C source files
If there should be some sort of separator it is better to use comment
with the filename, copyright, description, license information and
authors.

Found by:

git grep -nH '^$' | grep '\.[ch]:1:'

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-03-18 12:17:12 +01:00
Felix Geyer
29ea8a9b64 virt-aa-helper: handle 9pfs
Make virt-aa-helper create rules to allow VMs access to filesystem
mounts from the host.

Signed-off-by: Felix Geyer <debfx@fobos.de>
Signed-off-by: Hiroshi Miura <miurahr@linux.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: Guido Günther <agx@sigxcpu.org>
2014-03-17 20:53:39 +01:00
Michal Privoznik
f5796b61cc virSecurityDACSetSecurityImageLabel: Unmark @def as unused
The @def is clearly used just a few lines below. There's no need to use
ATTRIBUTE_UNUSED for it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-03-11 11:18:06 +01:00
Cédric Bosdonnat
9194ccecf1 apparmor: handle "none" type 2014-03-04 11:26:59 +00:00
Cédric Bosdonnat
500b2e9655 apparmor: add debug traces when changing profile.
The reason for these is that aa-status doesn't show the process using
the profile as they are in another namespace.
2014-03-04 11:07:05 +00:00
Cédric Bosdonnat
43c030f046 LXC driver: generate apparmor profiles for guests
use_apparmor() was first designed to be called from withing libvirtd,
but libvirt_lxc also uses it. in libvirt_lxc, there is no need to check
whether to use apparmor or not: just use it if possible.
2014-03-04 11:07:05 +00:00
Ján Tomko
0db9b0883c Generate a valid imagelabel even for type 'none'
Commit 2ce63c1 added imagelabel generation when relabeling is turned
off. But we weren't filling out the sensitivity for type 'none' labels,
resulting in an invalid label:

$ virsh managedsave domain
error: unable to set security context 'system_u:object_r:svirt_image_t'
on fd 28: Invalid argument
2014-02-05 19:47:30 +01:00
Osier Yang
10c9ceff6d util: Add one argument for several scsi utils
To support passing the path of the test data to the utils, one
more argument is added to virSCSIDeviceGetSgName,
virSCSIDeviceGetDevName, and virSCSIDeviceNew, and the related
code is changed accordingly.

Later tests for the scsi utils will be based on this patch.

Signed-off-by: Osier Yang <jyang@redhat.com>
2014-01-30 15:48:28 +08:00
Osier Yang
2b66504ded util: Add "shareable" field for virSCSIDevice struct
Unlike the host devices of other types, SCSI host device XML supports
"shareable" tag. This patch introduces it for the virSCSIDevice struct
for a later patch use (to detect if the SCSI device is shareable when
preparing the SCSI host device in QEMU driver).
2014-01-23 17:52:33 +08:00
Michal Privoznik
d1fdecb624 virSecuritySELinuxSetFileconHelper: Don't fail on read-only NFS
https://bugzilla.redhat.com/show_bug.cgi?id=996543

When starting up a domain, the SELinux labeling is done depending on
current configuration. If the labeling fails we check for possible
causes, as not all labeling failures are fatal. For example, if the
labeled file is on NFS which lacks SELinux support, the file can still
be readable to qemu process. These cases are distinguished by the errno
code: NFS without SELinux support returns EOPNOTSUPP. However, we were
missing one scenario. In case there's a read-only disk on a read-only
NFS (and possibly any FS) and the labeling is just optional (not
explicitly requested in the XML) there's no need to make the labeling
error fatal. In other words, read-only file on read-only NFS can fail to
be labeled, but be readable at the same time.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-01-17 13:35:01 +01:00
Eric Blake
baa7244951 maint: improve VIR_ERR_NO_SUPPORT usage
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>
2014-01-04 12:15:08 -07:00
Daniel P. Berrange
d75d8b46f8 Don't overwrite errors from virConfReadFile
The SELinux security driver would overwrite errors from the
virConfReadFile function.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-12-04 15:40:23 +00:00
Daniel P. Berrange
2b510e4903 Fix off-by-1 in default SELinux MCS range
For a while we're have random failures of 'securityselinuxtest'
which were not at all reproducible. Fortunately we finally
caught a failure with VIR_TEST_DEBUG=1 enabled. This revealed

TEST: securityselinuxtest
 1) GenLabel "dynamic unconfined, s0, c0.c1023"                       ... OK
 2) GenLabel "dynamic unconfined, s0, c0.c1023"                       ... OK
 3) GenLabel "dynamic unconfined, s0, c0.c1023"                       ... OK
 4) GenLabel "dynamic virtd, s0, c0.c1023"                            ... OK
 5) GenLabel "dynamic virtd, s0, c0.c10"                              ... OK
 6) GenLabel "dynamic virtd, s2-s3, c0.c1023"                         ... OK
 7) GenLabel "dynamic virtd, missing range"                           ... Category two 1024 is out of range 0-1023
FAILED
FAIL: securityselinuxtest

And sure enough we had an off-by-1 in the MCS range code when
the current process has no range set. The test suite randomly
allocates 2 categories from 0->1024 so the chances of hitting
this in the test suite were slim indeed :-)

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-11-20 13:09:00 +00:00
Eric Blake
fb8613525d maint: avoid further typedef accidents
To make it easier to forbid future attempts at a confusing typedef
name ending in Ptr that isn't actually a pointer, insist that we
follow our preferred style of 'typedef foo *fooPtr'.

* cfg.mk (sc_forbid_const_pointer_typedef): Enforce consistent
style, to prevent issue fixed in previous storage patch.
* src/conf/capabilities.h (virCapsPtr): Fix offender.
* src/security/security_stack.c (virSecurityStackItemPtr):
Likewise.
* tests/qemucapabilitiestest.c (testQemuDataPtr): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-10-30 17:02:12 -06:00
John Ferlan
aa42bb1700 Add '+' to uid/gid printing for label processing
To ensure proper processing by virGetUserID() and virGetGroupID()
of a uid/gid add a "+" prior to the uid/gid to denote it's really
a uid/gid for the label.
2013-10-29 17:10:15 -04:00
Peter Krempa
8e362a8955 apparmor: Fix typo in function name in driver struct initialization
Commit 64a68a4a introduced a typo in the initialization of the apparmor
driver structure breaking the build with apparmor enabled.
2013-10-29 17:01:22 +01:00
Giuseppe Scrivano
64a68a4a09 security: add new internal function "virSecurityManagerGetBaseLabel"
virSecurityManagerGetBaseLabel queries the default settings used by
a security model.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
2013-10-29 06:57:07 -06:00
Giuseppe Scrivano
4387132f31 security: use a single function to set DAC user and group
Merge the functions 'virSecurityDACSetUser' and
'virSecurityDACSetGroup' into 'virSecurityDACSetUserAndGroup'.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
2013-10-29 06:55:09 -06:00
Eric Blake
84e8091796 maint: avoid 'const fooPtr' in security
'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/security.

* src/security/security_apparmor.c (reload_profile)
(AppArmorSetSecurityHostdevLabelHelper)
(AppArmorReleaseSecurityLabel, AppArmorRestoreSecurityAllLabel)
(AppArmorSetSecurityProcessLabel)
(AppArmorSetSecurityChildProcessLabel)
(AppArmorSetSecurityImageLabel, AppArmorSecurityVerify)
(AppArmorSetSecurityHostdevLabel)
(AppArmorRestoreSecurityHostdevLabel, AppArmorSetFDLabel): Drop
needless const.
* src/security/security_selinux.c
(virSecuritySELinuxSetSecurityFileLabel): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-10-14 14:34:38 -06:00
Ján Tomko
f1bdcb2be9 selinux: Only close the selabel_handle once
On selinux driver initialization failure (missing/incorrectly
formatted contexts file), selabel_handle was closed twice.

Introduced by 6159710.
2013-10-01 15:00:07 +02:00
Michal Privoznik
32d7e2481b AppArmorSetSecurityImageLabel: Avoid use of uninitialized variable
The @profile_name variable can be used uninitialized.
2013-09-04 08:47:00 +02:00
Eric Blake
745aa55fbf security: provide supplemental groups even when parsing label (CVE-2013-4291)
Commit 29fe5d7 (released in 1.1.1) introduced a latent problem
for any caller of virSecurityManagerSetProcessLabel and where
the domain already had a uid:gid label to be parsed.  Such a
setup would collect the list of supplementary groups during
virSecurityManagerPreFork, but then ignores that information,
and thus fails to call setgroups() to adjust the supplementary
groups of the process.

Upstream does not use virSecurityManagerSetProcessLabel for
qemu (it uses virSecurityManagerSetChildProcessLabel instead),
so this problem remained latent until backporting the initial
commit into v0.10.2-maint (commit c061ff5, released in 0.10.2.7),
where virSecurityManagerSetChildProcessLabel has not been
backported.  As a result of using a different code path in the
backport, attempts to start a qemu domain that runs as qemu:qemu
will end up with supplementary groups unchanged from the libvirtd
parent process, rather than the desired supplementary groups of
the qemu user.  This can lead to failure to start a domain
(typical Fedora setup assigns user 107 'qemu' to both group 107
'qemu' and group 36 'kvm', so a disk image that is only readable
under kvm group rights is locked out).  Worse, it is a security
hole (the qemu process will inherit supplemental group rights
from the parent libvirtd process, which means it has access
rights to files owned by group 0 even when such files should
not normally be visible to user qemu).

LXC does not use the DAC security driver, so it is not vulnerable
at this time.  Still, it is better to plug the latent hole on
the master branch first, before cherry-picking it to the only
vulnerable branch v0.10.2-maint.

* src/security/security_dac.c (virSecurityDACGetIds): Always populate
groups and ngroups, rather than only when no label is parsed.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-29 08:43:03 -06:00
Eric Blake
0f082e699e selinux: distinguish failure to label from request to avoid label
https://bugzilla.redhat.com/show_bug.cgi?id=924153

Commit 904e05a2 (v0.9.9) added a per-<disk> seclabel element with
an attribute relabel='no' in order to try and minimize the
impact of shutdown delays when an NFS server disappears.  The idea
was that if a disk is on NFS and can't be labeled in the first
place, there is no need to attempt the (no-op) relabel on domain
shutdown.  Unfortunately, the way this was implemented was by
modifying the domain XML so that the optimization would survive
libvirtd restart, but in a way that is indistinguishable from an
explicit user setting.  Furthermore, once the setting is turned
on, libvirt avoids attempts at labeling, even for operations like
snapshot or blockcopy where the chain is being extended or pivoted
onto non-NFS, where SELinux labeling is once again possible.  As
a result, it was impossible to do a blockcopy to pivot from an
NFS image file onto a local file.

The solution is to separate the semantics of a chain that must
not be labeled (which the user can set even on persistent domains)
vs. the optimization of not attempting a relabel on cleanup (a
live-only annotation), and using only the user's explicit notation
rather than the optimization as the decision on whether to skip
a label attempt in the first place.  When upgrading an older
libvirtd to a newer, an NFS volume will still attempt the relabel;
but as the avoidance of a relabel was only an optimization, this
shouldn't cause any problems.

In the ideal future, libvirt will eventually have XML describing
EVERY file in the backing chain, with each file having a separate
<seclabel> element.  At that point, libvirt will be able to track
more closely which files need a relabel attempt at shutdown.  But
until we reach that point, the single <seclabel> for the entire
<disk> chain is treated as a hint - when a chain has only one
file, then we know it is accurate; but if the chain has more than
one file, we have to attempt relabel in spite of the attribute,
in case part of the chain is local and SELinux mattered for that
portion of the chain.

* src/conf/domain_conf.h (_virSecurityDeviceLabelDef): Add new
member.
* src/conf/domain_conf.c (virSecurityDeviceLabelDefParseXML):
Parse it, for live images only.
(virSecurityDeviceLabelDefFormat): Output it.
(virDomainDiskDefParseXML, virDomainChrSourceDefParseXML)
(virDomainDiskSourceDefFormat, virDomainChrDefFormat)
(virDomainDiskDefFormat): Pass flags on through.
* src/security/security_selinux.c
(virSecuritySELinuxRestoreSecurityImageLabelInt): Honor labelskip
when possible.
(virSecuritySELinuxSetSecurityFileLabel): Set labelskip, not
norelabel, if labeling fails.
(virSecuritySELinuxSetFileconHelper): Fix indentation.
* docs/formatdomain.html.in (seclabel): Document new xml.
* docs/schemas/domaincommon.rng (devSeclabel): Allow it in RNG.
* tests/qemuxml2argvdata/qemuxml2argv-seclabel-*-labelskip.xml:
* tests/qemuxml2argvdata/qemuxml2argv-seclabel-*-labelskip.args:
* tests/qemuxml2xmloutdata/qemuxml2xmlout-seclabel-*-labelskip.xml:
New test files.
* tests/qemuxml2argvtest.c (mymain): Run the new tests.
* tests/qemuxml2xmltest.c (mymain): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-08-20 10:39:03 -06:00
Martin Kletzander
bba579b6e0 Expose ownership ID parsing
Parsing 'user:group' is useful even outside the DAC security driver,
so expose the most abstract function which has no DAC security driver
bits in itself.
2013-07-24 14:29:11 +02:00
Eric Blake
bfc183c1e3 security: fix deadlock with prefork
Attempts to start a domain with both SELinux and DAC security
modules loaded will deadlock; latent problem introduced in commit
fdb3bde and exposed in commit 29fe5d7.  Basically, when recursing
into the security manager for other driver's prefork, we have to
undo the asymmetric lock taken at the manager level.

Reported by Jiri Denemark, with diagnosis help from Dan Berrange.

* src/security/security_stack.c (virSecurityStackPreFork): Undo
extra lock grabbed during recursion.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-07-19 09:15:22 -06:00
Eric Blake
29fe5d745f security_dac: compute supplemental groups before fork
Commit 75c1256 states that virGetGroupList must not be called
between fork and exec, then commit ee777e99 promptly violated
that for lxc's use of virSecurityManagerSetProcessLabel.  Hoist
the supplemental group detection to the time that the security
manager needs to fork.  Qemu is safe, as it uses
virSecurityManagerSetChildProcessLabel which in turn uses
virCommand to determine supplemental groups.

This does not fix the fact that virSecurityManagerSetProcessLabel
calls virSecurityDACParseIds calls parseIds which eventually
calls getpwnam_r, which also violates fork/exec async-signal-safe
safety rules, but so far no one has complained of hitting
deadlock in that case.

* src/security/security_dac.c (_virSecurityDACData): Track groups
in private data.
(virSecurityDACPreFork): New function, to set them.
(virSecurityDACClose): Clean up new fields.
(virSecurityDACGetIds): Alter signature.
(virSecurityDACSetSecurityHostdevLabelHelper)
(virSecurityDACSetChardevLabel, virSecurityDACSetProcessLabel)
(virSecurityDACSetChildProcessLabel): Update callers.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-07-18 15:35:30 -06:00
Eric Blake
fdb3bde31c security: framework for driver PreFork handler
A future patch wants the DAC security manager to be able to safely
get the supplemental group list for a given uid, but at the time
of a fork rather than during initialization so as to pick up on
live changes to the system's group database.  This patch adds the
framework, including the possibility of a pre-fork callback
failing.

For now, any driver that implements a prefork callback must be
robust against the possibility of being part of a security stack
where a later element in the chain fails prefork.  This means
that drivers cannot do any action that requires a call to postfork
for proper cleanup (no grabbing a mutex, for example).  If this
is too prohibitive in the future, we would have to switch to a
transactioning sequence, where each driver has (up to) 3 callbacks:
PreForkPrepare, PreForkCommit, and PreForkAbort, to either clean
up or commit changes made during prepare.

* src/security/security_driver.h (virSecurityDriverPreFork): New
callback.
* src/security/security_manager.h (virSecurityManagerPreFork):
Change signature.
* src/security/security_manager.c (virSecurityManagerPreFork):
Optionally call into driver, and allow returning failure.
* src/security/security_stack.c (virSecurityDriverStack):
Wrap the handler for the stack driver.
* src/qemu/qemu_process.c (qemuProcessStart): Adjust caller.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-07-18 15:19:36 -06:00
Michal Privoznik
ba44dd2453 virSecurityManagerGenLabel: Skip seclabels without model
While generating seclabels, we check the seclabel stack if required
driver is in the stack. If not, an error is returned. However, it is
possible for a seclabel to not have any model set (happens with LXC
domains that have just <seclabel type='none'>). If that's the case,
we should just skip the iteration instead of calling STREQ(NULL, ...)
and SIGSEGV-ing subsequently.
2013-07-17 12:36:47 +02:00
Eric Blake
ee777e9949 util: make virSetUIDGID async-signal-safe
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>
2013-07-11 15:46:42 -06:00
Daniel P. Berrange
716961372e Convert 'int i' to 'size_t i' in src/security files
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>
2013-07-10 17:40:14 +01:00
Michal Privoznik
a72715e0a8 Adapt to VIR_ALLOC and virAsprintf in src/security/* 2013-07-10 11:07:32 +02:00
Michal Privoznik
8290cbbc38 viralloc: Report OOM error on failure
Similarly to VIR_STRDUP, we want the OOM error to be reported in
VIR_ALLOC and friends.
2013-07-10 11:07:31 +02:00
Peter Krempa
2ce63c1611 selinux: Always generate imagelabel
The imagelabel SELinux label was only generated when relabeling was
enabled. This prohibited labeling of files created by libvirt that need
to be labeled even if relabeling is turned off.

The only codepath this change has direct impact on is labeling of FDs
passed to qemu which is always safe in current state.
2013-07-08 15:04:20 +02:00
Peter Krempa
e45ee23c59 selinux: Cleanup coding style 2013-07-08 15:04:07 +02:00
Laine Stump
1d829e1306 pci: rename virPCIDeviceGetVFIOGroupDev to virPCIDeviceGetIOMMUGroupDev
I realized after the fact that it's probably better in the long run to
give this function a name that matches the name of the link used in
sysfs to hold the group (iommu_group).

I'm changing it now because I'm about to add several more functions
that deal with iommu groups.
2013-06-25 18:07:38 -04:00
Ján Tomko
0b466db29b selinux: assume 's0' if the range is empty
This fixes a crash:
https://bugzilla.redhat.com/show_bug.cgi?id=969878
2013-06-11 13:13:43 +02:00
Eric Blake
146ba114a5 syntax: prefer space after semicolon in for loop
I noticed several unusual spacings in for loops, and decided to
fix them up.  See the next commit for the syntax check that found
all of these.

* examples/domsuspend/suspend.c (main): Fix spacing.
* python/libvirt-override.c: Likewise.
* src/conf/interface_conf.c: Likewise.
* src/security/virt-aa-helper.c: Likewise.
* src/util/virconf.c: Likewise.
* src/util/virhook.c: Likewise.
* src/util/virlog.c: Likewise.
* src/util/virsocketaddr.c: Likewise.
* src/util/virsysinfo.c: Likewise.
* src/util/viruuid.c: Likewise.
* src/vbox/vbox_tmpl.c: Likewise.
* src/xen/xen_hypervisor.c: Likewise.
* tools/virsh-domain-monitor.c (vshDomainStateToString): Drop
default case, to let compiler check us.
* tools/virsh-domain.c (vshDomainVcpuStateToString): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-05-28 07:56:07 -06:00
Osier Yang
fb6a05e75d security_dac: Fix the coding style
Pushed under trivial rule.
2013-05-24 23:33:09 +08:00
Michal Privoznik
aaa42912ae Adapt to VIR_STRDUP and VIR_STRNDUP in src/security/* 2013-05-23 09:56:38 +02:00