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.
In the Ubuntu development release we recently got a new udev that
moves /var/run to /run, /var/lock to /run/lock and /dev/shm to /run/shm.
This change in udev requires updating the apparmor security driver in
libvirt[1].
Attached is a patch that:
* adjusts src/security/virt-aa-helper.c to allow both
LOCALSTATEDIR/run/libvirt/**/%s.pid and /run/libvirt/**/%s.pid. While
the profile is not as precise, LOCALSTATEDIR/run/ is typically a symlink
to /run/ anyway, so there is no additional access (remember that
apparmor resolves symlinks, which is why this is still required even
if /var/run points to /run).
* adjusts example/apparmor/libvirt-qemu paths for /dev/shm
[1]https://launchpad.net/bugs/810270
--
Jamie Strandboge | http://www.canonical.com
The drivers were accepting domain configs without checking if those
were actually meant for them. For example the LXC driver happily
accepts configs with type QEMU.
Add a check for the expected domain types to the virDomainDefParse*
functions.
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/
Commit 12317957ec introduced an incompatible
architectural change for the AppArmor security driver. Specifically,
virSecurityManagerSetAllLabel() is now called much later in
src/qemu/qemu_process.c:qemuProcessStart(). Previously, SetAllLabel() was
called immediately after GenLabel() such that after the dynamic label (profile
name) was generated, SetAllLabel() would be called to create and load the
AppArmor profile into the kernel before qemuProcessHook() was executed. With
12317957ec, qemuProcessHook() is now called
before SetAllLabel(), such that aa_change_profile() ends up being called
before the AppArmor profile is loaded into the kernel (via ProcessLabel() in
qemuProcessHook()).
This patch addresses the change by making GenLabel() load the AppArmor
profile into the kernel after the label (profile name) is generated.
SetAllLabel() is then adjusted to only reload_profile() and append stdin_fn to
the profile when it is specified. This also makes the AppArmor driver work
like its SELinux counterpart with regard to SetAllLabel() and stdin_fn.
Bug-Ubuntu: https://launchpad.net/bugs/801569
During a savevm operation, libvirt will now use fd migration if qemu
supports it. When the AppArmor driver is enabled, AppArmorSetFDLabel()
is used but since this function simply returns '0', the dynamic AppArmor
profile is not updated and AppArmor blocks access to the save file. This
patch implements AppArmorSetFDLabel() to get the pathname of the file by
resolving the fd symlink in /proc, and then gives that pathname to
reload_profile(), which fixes 'virsh save' when AppArmor is enabled.
Reference: https://launchpad.net/bugs/795800
This fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=702044https://bugzilla.redhat.com/show_bug.cgi?id=709454
Both of these complain of a failure to use an image file that resides
on a read-only NFS volume. The function in the DAC security driver
that chowns image files to the qemu user:group before using them
already has special cases to ignore failure of chown on read-only file
systems, and in a few other cases, but it hadn't been checking for
EINVAL, which is what is returned if the qemu user doesn't even exist
on the NFS server.
Since the explanation of EINVAL in the chown man page almost exactly
matches the log message already present for the case of EOPNOTSUPP,
I've just added EINVAL to that same conditional.
Regression introduced in commit d6623003 (v0.8.8) - using the
wrong sizeof operand meant that security manager private data
was overlaying the allowDiskFormatProbing member of struct
_virSecurityManager. This reopens disk probing, which was
supposed to be prevented by the solution to CVE-2010-2238.
* src/security/security_manager.c
(virSecurityManagerGetPrivateData): Use correct offset.
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
We already have virAsprintf, so picking a similar name helps for
seeing a similar purpose. Furthermore, the prefix V before printf
generally implies 'va_list', even though this variant was '...', and
the old name got in the way of adding a new va_list version.
global rename performed with:
$ git grep -l virBufferVSprintf \
| xargs -L1 sed -i 's/virBufferVSprintf/virBufferAsprintf/g'
then revert the changes in ChangeLog-old.
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.
Child processes don't always reach _exit(); if they die from a
signal, then any messages should still be accurate. Most users
either expect a 0 status (thankfully, if status==0, then
WIFEXITED(status) is true and WEXITSTATUS(status)==0 for all
known platforms) or were filtering on WIFEXITED before printing
a status, but a few were missing this check. Additionally,
nwfilter_ebiptables_driver was making an assumption that works
on Linux (where WEXITSTATUS shifts and WTERMSIG just masks)
but fails on other platforms (where WEXITSTATUS just masks and
WTERMSIG shifts).
* src/util/command.h (virCommandTranslateStatus): New helper.
* src/libvirt_private.syms (command.h): Export it.
* src/util/command.c (virCommandTranslateStatus): New function.
(virCommandWait): Use it to also diagnose status from signals.
* src/security/security_apparmor.c (load_profile): Likewise.
* src/storage/storage_backend.c
(virStorageBackendQEMUImgBackingFormat): Likewise.
* src/util/util.c (virExecDaemonize, virRunWithHook)
(virFileOperation, virDirCreate): Likewise.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c (ebiptablesExecCLI):
Likewise.
On cygwin:
CC libvirt_driver_security_la-security_dac.lo
security/security_dac.c: In function 'virSecurityDACSetProcessLabel':
security/security_dac.c:618: warning: format '%d' expects type 'int', but argument 7 has type 'uid_t' [-Wformat]
We've done this before (see src/util/util.c).
* src/security/security_dac.c (virSecurityDACSetProcessLabel): On
cygwin, uid_t is a 32-bit long.
virSecurityDAC{Set,Restore}ChardevCallback expect virSecurityManagerPtr,
but are passed virDomainObjPtr instead. This makes
virSecurityDACSetChardevLabel set a wrong uid/gid on chardevs. This
patch fixes this behaviour.
Signed-off-by: Soren Hansen <soren@linux2go.dk>
Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'
followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.
* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.
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().
If the XML security model is NULL, it is assumed that the current
model will be used with dynamic labelling. The verify step is
meaningless and potentially crashes if dereferencing NULL
* src/security/security_manager.c: Skip NULL model on verify
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
Include locale.h for setlocale().
Revert the usage string back to it's original form.
Use puts() instead of fputs(), as fputs() expects a FILE*.
Add closing parenthesis to some vah_error() calls.
Use argv[0] instead of an undefined argv0.
These messages are visible to the user, so they should be
consistently translated.
* cfg.mk (msg_gen_function): Add vah_error, vah_warning.
* src/security/virt-aa-helper.c: Translate messages.
(catchXMLError): Fix capitalization.
Per the gettext developer:
http://lists.gnu.org/archive/html/bug-gnu-utils/2010-10/msg00019.htmlhttp://lists.gnu.org/archive/html/bug-gnu-utils/2010-10/msg00021.html
gettext() doesn't work correctly on all platforms unless you have
called setlocale(). Furthermore, gnulib's gettext.h has provisions
for setting up a default locale, which is the preferred method for
libraries to use gettext without having to call textdomain() and
override the main program's default domain (virInitialize already
calls bindtextdomain(), but this is insufficient without the
setlocale() added in this patch; and a redundant bindtextdomain()
in this patch doesn't hurt, but serves as a good example for other
packages that need to bind a second translation domain).
This patch is needed to silence a new gnulib 'make syntax-check'
rule in the next patch.
* daemon/libvirtd.c (main): Setup locale and gettext.
* src/lxc/lxc_controller.c (main): Likewise.
* src/security/virt-aa-helper.c (main): Likewise.
* src/storage/parthelper.c (main): Likewise.
* tools/virsh.c (main): Fix exit status.
* src/internal.h (DEFAULT_TEXT_DOMAIN): Define, for gettext.h.
(_): Simplify definition accordingly.
* po/POTFILES.in: Add src/storage/parthelper.c.
When <uuid> is not in the XML, a virUUIDGenerate() ends up being called which
is unnecessary and can lead to crashes if /dev/urandom isn't available
because virRandomInitialize() is not called within virt-aa-helper. This patch
adds verify_xpath_context() and updates caps_mockup() to use it.
Bug-Ubuntu: https://launchpad.net/bugs/672943
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.
Description: Implement AppArmorSetSecurityHostdevLabel() and
AppArmorRestoreSecurityHostdevLabel() for hostdev and pcidev attach.
virt-aa-helper also has to be adjusted because *FileIterate() is used for pci
and usb devices and the corresponding XML for hot attached hostdev and pcidev
is not in the XML passed to virt-aa-helper. The new '-F filename' option is
added to append a rule to the profile as opposed to the existing '-f
filename', which rewrites the libvirt-<uuid>.files file anew. This new '-F'
option will append a rule to an existing libvirt-<uuid>.files if it exists,
otherwise it acts the same as '-f'.
load_profile() and reload_profile() have been adjusted to add an 'append'
argument, which when true will use '-F' instead of '-f' when executing
virt-aa-helper.
All existing calls to load_profile() and reload_profile() have been adjusted
to use the old behavior (ie append==false) except AppArmorSetSavedStateLabel()
where it made sense to use the new behavior.
This patch also adds tests for '-F'.
Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/640993
Description: Check for VIR_DOMAIN_CHR_TYPE in serial ports and add 'rw' for
defined serial ports, parallel ports and channels
Bug-Ubuntu: LP: #578527, LP: #609055
Commit 68719c4bdd added the
p option to control disk format probing, but it wasn't added
to the getopt_long optstring parameter.
Add the p option to the getopt_long optstring parameter.
Commit a885334499 added this
function and wrapped vah_add_file in it. vah_add_file may
return -1, 0, 1. It returns 1 in case the call to valid_path
detects a restricted file. The original code treated a return
value != 0 as error. The refactored code treats a return
value < 0 as error. This triggers segfault in virt-aa-helper
and breaks virt-aa-helper-test for the restricted file tests.
Make sure that add_file_path returns -1 on error.
virt-aa-helper used to ignore errors when opening files.
Commit a885334499 refactored
the related code and changed this behavior. virt-aa-helper
didn't ignore open errors anymore and virt-aa-helper-test
fails.
Make sure that virt-aa-helper ignores open errors again.
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.
* src/security/virt-aa-helper.c: adjust virt-aa-helper to handle pci
devices. Update valid_path() to have an override array to check against,
and add "/sys/devices/pci" to it. Then rename file_iterate_cb() to
file_iterate_hostdev_cb() and create file_iterate_pci_cb() based on it
To avoid an error when hitting the <seclabel...> definition
* src/security/virt-aa-helper.c: add VIR_DOMAIN_XML_INACTIVE flag
to virDomainDefParseString
Don't exit with error if the user unloaded the profile outside of
libvirt
* src/security/virt-aa-helper.c: check the exit error from apparmor_parser
before exiting with a failure
The calls to virExec() in security_apparmor.c when
invoking virt-aa-helper use VIR_EXEC_CLEAR_CAPS. When compiled without
libcap-ng, this is not a problem (it's effectively a no-op) but with
libcap-ng this causes MAC_ADMIN to be cleared. MAC_ADMIN is needed by
virt-aa-helper to manipulate apparmor profiles and without it VMs will
not start[1]. This patch calls virExec with the default VIR_EXEC_NONE
instead.
* src/security/security_apparmor.c: fallback to VIR_EXEC_NONE flags for
virExec of virt_aa_helper
(suggested by Daniel Berrange, tested by Dan Kenigsberg)
virStorageFileGetMetadata will fail for disk images that are stored on
a root-squash NFS share that isn't world-readable.
SELinuxSetSecurityImageLabel is called during the startup of every
domain (as long as security_driver != "none"), and it will propogate
the error from virStorageFileGetMetadata, causing the domain startup
to fail. This is, however, a common scenario when qemu is run as a
non-root user and the disk image is stored on NFS.
Ignoring this failure (which doesn't matter in this case, since the
next thing done by SELinuxSetSecurityImageLabel - setting the file
context - will also fail (and that function already ignores failures
due to root-squash NFS) will allow us to continue bringing up the
domain. The result is that we don't need to disable the entire
security driver just because a domain's disk image is stored on
root-squashed NFS.
Changeset
commit 5073aa994a
Author: Cole Robinson <crobinso@redhat.com>
Date: Mon Jan 11 11:40:46 2010 -0500
Added support for product/vendor based passthrough, but it only
worked at the security driver layer. The main guest XML config
was not updated with the resolved bus/device ID. When the QEMU
argv refactoring removed use of product/vendor, this then broke
launching guests.
THe solution is to move the product/vendor resolution up a layer
into the QEMU driver. So the first thing QEMU does is resolve
the product/vendor to a bus/device and updates the XML config
with this info. The rest of the code, including security drivers
and QEMU argv generated can now rely on bus/device always being
set.
* src/util/hostusb.c, src/util/hostusb.h: Split vendor/product
resolution code out of usbGetDevice and into usbFindDevice.
Add accessors for bus/device ID
* src/security/virt-aa-helper.c, src/security/security_selinux.c,
src/qemu/qemu_security_dac.c: Remove vendor/product from the
usbGetDevice() calls
* src/qemu/qemu_driver.c: Use usbFindDevice to resolve vendor/product
into a bus/device ID
The virRaiseError macro inside of virSecurityReportError expands to
virRaiseErrorFull and includes the __FILE__, __FUNCTION__ and __LINE__
information. But this three values are always the same for every call
to virSecurityReportError and do not reflect the actual error context.
Converting virSecurityReportError into a macro results in getting the
correct __FILE__, __FUNCTION__ and __LINE__ information.
All callers now pass a NULL virConnectPtr into the USB/PCi device
iterator functions. Therefore the virConnectPtr arg can now be
removed from these functions
* src/util/hostusb.h, src/util/hostusb.c: Remove virConnectPtr
from usbDeviceFileIterate
* src/util/pci.c, src/util/pci.h: Remove virConnectPtr arg from
pciDeviceFileIterate
* src/qemu/qemu_security_dac.c, src/security/security_selinux.c: Update
to drop redundant virConnectPtr arg
The virConnectPtr is no longer required for error reporting since
that is recorded in a thread local. Remove use of virConnectPtr
from all APIs in security_driver.{h,c} and update all callers to
match
The current security driver architecture has the following
split of logic
* domainGenSecurityLabel
Allocate the unique label for the domain about to be started
* domainGetSecurityLabel
Retrieve the current live security label for a process
* domainSetSecurityLabel
Apply the previously allocated label to the current process
Setup all disk image / device labelling
* domainRestoreSecurityLabel
Restore the original disk image / device labelling.
Release the unique label for the domain
The 'domainSetSecurityLabel' method is special because it runs
in the context of the child process between the fork + exec.
This is require in order to set the process label. It is not
required in order to label disks/devices though. Having the
disk labelling code run in the child process limits what it
can do.
In particularly libvirtd would like to remember the current
disk image label, and only change shared image labels for the
first VM to start. This requires use & update of global state
in the libvirtd daemon, and thus cannot run in the child
process context.
The solution is to split domainSetSecurityLabel into two parts,
one applies process label, and the other handles disk image
labelling. At the same time domainRestoreSecurityLabel is
similarly split, just so that it matches the style. Thus the
previous 4 methods are replaced by the following 6 new methods
* domainGenSecurityLabel
Allocate the unique label for the domain about to be started
No actual change here.
* domainReleaseSecurityLabel
Release the unique label for the domain
* domainGetSecurityProcessLabel
Retrieve the current live security label for a process
Merely renamed for clarity.
* domainSetSecurityProcessLabel
Apply the previously allocated label to the current process
* domainRestoreSecurityAllLabel
Restore the original disk image / device labelling.
* domainSetSecurityAllLabel
Setup all disk image / device labelling
The SELinux and AppArmour drivers are then updated to comply with
this new spec. Notice that the AppArmour driver was actually a
little different. It was creating its profile for the disk image
and device labels in the 'domainGenSecurityLabel' method, where as
the SELinux driver did it in 'domainSetSecurityLabel'. With the
new method split, we can have consistency, with both drivers doing
that in the domainSetSecurityAllLabel method.
NB, the AppArmour changes here haven't been compiled so may not
build.
The QEMU driver is doing 90% of the calls to check for static vs
dynamic labelling. Except it is forgetting todo so in many places,
in particular hotplug is mistakenly assigning disk labels. Move
all this logic into the security drivers themselves, so the HV
drivers don't have to think about it.
* src/security/security_driver.h: Add virDomainObjPtr parameter
to virSecurityDomainRestoreHostdevLabel and to
virSecurityDomainRestoreSavedStateLabel
* src/security/security_selinux.c, src/security/security_apparmor.c:
Add explicit checks for VIR_DOMAIN_SECLABEL_STATIC and skip all
chcon() code in those cases
* src/qemu/qemu_driver.c: Remove all checks for VIR_DOMAIN_SECLABEL_STATIC
or VIR_DOMAIN_SECLABEL_DYNAMIC. Add missing checks for possibly NULL
driver entry points.
Based off how QEMU does it, look through /sys/bus/usb/devices/* for
matching vendor:product info, and if found, use info from the surrounding
files to build the device's /dev/bus/usb path.
This fixes USB device assignment by vendor:product when running qemu
as non-root (well, it should, but for some reason I couldn't reproduce
the failure people are seeing in [1], but it appears to work properly)
[1] https://bugzilla.redhat.com/show_bug.cgi?id=542450
Replace free(virBufferContentAndReset()) with virBufferFreeAndReset().
Update documentation and replace all remaining calls to free() with
calls to VIR_FREE(). Also add missing calls to virBufferFreeAndReset()
and virReportOOMError() in OOM error cases.
Introduce a new type="dir" mode for <disks> that allows use of
QEMU's virtual FAT block device driver. eg
<disk type='dir' device='floppy'>
<source dir='/tmp/test'/>
<target dev='fda' bus='fdc'/>
<readonly/>
</disk>
gets turned into
-drive file=fat:floppy:/tmp/test,if=floppy,index=0
Only read-only disks are supported with virtual FAT mode
* src/conf/domain_conf.c, src/conf/domain_conf.h: Add type="dir"
* docs/schemas/domain.rng: Document new disk type
* src/xen/xend_internal.c, src/xen/xm_internal.c: Raise error for
unsupported disk types
* tests/qemuxml2argvdata/qemuxml2argv-disk-cdrom-empty.args: Fix
empty disk file handling
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fat.args,
tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fat.xml,
tests/qemuxml2argvdata/qemuxml2argv-floppy-drive-fat.args,
tests/qemuxml2argvdata/qemuxml2argv-floppy-drive-fat.xml
tests/qemuxml2argvtest.c: Test QEMU vitual FAT driver
* src/qemu/qemu_conf.c: Support generating fat:/some/dir type
disk args
* src/security/security_selinux.c: Temporarily skip labelling
of directory based disks
Fixes https://launchpad.net/bugs/453335
* src/security/virt-aa-helper.c: suppress confusing and misleading
apparmor denied message when kvm/qemu tries to open a libvirt specified
readonly file (such as a cdrom) with write permissions. libvirt uses
the readonly attribute for the security driver only, and has no way
of telling kvm/qemu that the device should be opened readonly
Fixes https://launchpad.net/bugs/460271
* src/security/virt-aa-helper.c: require absolute path for dynamic added
files. This is required by AppArmor and conveniently prevents adding
tcp consoles to the profile
* src/security/virt-aa-helper.c: get_definition() now calls the new
caps_mockup() function which will parse the XML for os.type,
os.type.arch and then sets the wordsize. These attributes are needed
only to get a valid virCapsPtr for virDomainDefParseString(). The -H
and -b options are now removed from virt-aa-helper (they weren't used
yet anyway).
* tests/virt-aa-helper-test: extend and fixes tests, chmod'ed 755
When running qemu:///system instance, libvirtd runs as root,
but QEMU may optionally be configured to run non-root. When
then saving a guest to a state file, the file is initially
created as root, and thus QEMU cannot write to it. It is also
missing labelling required to allow access via SELinux.
* src/qemu/qemu_driver.c: Set ownership on save image before
running migrate command in virDomainSave impl. Call out to
security driver to set save image labelling
* src/security/security_driver.h: Add driver APIs for setting
and restoring saved state file labelling
* src/security/security_selinux.c: Implement saved state file
labelling for SELinux
- Don't duplicate SystemError
- Use proper error code in domain_conf
- Fix a broken error call in qemu_conf
- Don't use VIR_ERR_ERROR in security driver (isn't a valid code in this case)
Nearly all of the methods in src/util/util.h have error codes that
must be checked by the caller to correct detect & report failure.
Add ATTRIBUTE_RETURN_CHECK to ensure compile time validation of
this
* daemon/libvirtd.c: Add explicit check on return value of virAsprintf
* src/conf/domain_conf.c: Add missing check on virParseMacAddr return
value status & report error
* src/network/bridge_driver.c: Add missing OOM check on virAsprintf
and report error
* src/qemu/qemu_conf.c: Add missing check on virParseMacAddr return
value status & report error
* src/security/security_selinux.c: Remove call to virRandomInitialize
that's done in libvirt.c already
* src/storage/storage_backend_logical.c: Add check & log on virRun
return status
* src/util/util.c: Add missing checks on virAsprintf/Run status
* src/util/util.h: Annotate all methods with ATTRIBUTE_RETURN_CHECK
if they return an error status code
* src/vbox/vbox_tmpl.c: Add missing check on virParseMacAddr
* src/xen/xm_internal.c: Add missing checks on virAsprintf
* tests/qemuargv2xmltest.c: Remove bogus call to virRandomInitialize()
* configure.in: look for AppArmor and devel
* src/security/security_apparmor.[ch] src/security/security_driver.c
src/Makefile.am: add and plug the new driver
* src/security/virt-aa-helper.c: new binary which is used exclusively by
the AppArmor security driver to manipulate AppArmor.
* po/POTFILES.in: registers the new files
* tests/Makefile.am tests/secaatest.c tests/virt-aa-helper-test:
tests for virt-aa-helper and the security driver, secaatest.c is
identical to seclabeltest.c except it initializes the 'apparmor'
driver instead of 'selinux'
When James Morris originally submitted his sVirt patches (as seen in
libvirt 0.6.1), he did not require on disk labelling for
virSecurityDomainRestoreImageLabel. A later commit[2] changed this
behavior to assume on disk labelling, which halts implementations for
path-based MAC systems such as AppArmor and TOMOYO where
vm->def->seclabel is required to obtain the label.
* src/security/security_driver.h src/qemu/qemu_driver.c
src/security/security_selinux.c: adds the 'virDomainObjPtr vm'
argument back to *RestoreImageLabel
A simple misplaced break out of a switch results in:
libvir: error : Failed to open file '/sys/bus/pci/devices/0000:00:54c./vendor': No such file or directory
libvir: error : Failed to open file '/sys/bus/pci/devices/0000:00:54c./device': No such file or directory
libvir: error : this function is not supported by the hypervisor: Failed to read product/vendor ID for 0000:00:54c.
when trying to passthrough a USB host device to qemu.
* src/security_selinux.c: fix a switch/break thinko
Use virStorageFileGetMetadata() to find any backing stores for images
and re-label them
Without this, qemu cannot access qcow2 backing files, see:
https://bugzilla.redhat.com/497131
* src/security/security_selinux.c: re-label backing store files in
SELinuxSetSecurityImageLabel()
