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CVE-2016-5008
Setting an empty graphics password is documented as a way to disable
VNC/SPICE access, but QEMU does not always behaves like that. VNC would
happily accept the empty password. Let's enforce the behavior by setting
password expiration to "now".
https://bugzilla.redhat.com/show_bug.cgi?id=1180092
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
(cherry picked from commit bb848feec0f3f10e92dd8e5231ae7aa89b5598f3)
The libvirt file system storage driver determines what file to
act on by concatenating the pool location with the volume name.
If a user is able to pick names like "../../../etc/passwd", then
they can escape the bounds of the pool. For that matter,
virStoragePoolListVolumes() doesn't descend into subdirectories,
so a user really shouldn't use a name with a slash.
Normally, only privileged users can coerce libvirt into creating
or opening existing files using the virStorageVol APIs; and such
users already have full privilege to create any domain XML (so it
is not an escalation of privilege). But in the case of
fine-grained ACLs, it is feasible that a user can be granted
storage_vol:create but not domain:write, and it violates
assumptions if such a user can abuse libvirt to access files
outside of the storage pool.
Therefore, prevent all use of volume names that contain "/",
whether or not such a name is actually attempting to escape the
pool.
This changes things from:
$ virsh vol-create-as default ../../../../../../etc/haha --capacity 128
Vol ../../../../../../etc/haha created
$ rm /etc/haha
to:
$ virsh vol-create-as default ../../../../../../etc/haha --capacity 128
error: Failed to create vol ../../../../../../etc/haha
error: Requested operation is not valid: volume name '../../../../../../etc/haha' cannot contain '/'
Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 034e47c338b13a95cf02106a3af912c1c5f818d7)
Since commit 8eb55d782a2b9afacc7938694891cc6fad7b42a5 libxml2 removes
two slashes from the URI when there is no server part. This is fixed
with beb7281055dbf0ed4d041022a67c6c5cfd126f25, but only if the calling
application calls xmlSaveUri() on URI that xmlURIParse() parsed. And
that is not the case in virURIFormat(). virURIFormat() accepts
virURIPtr that can be created without parsing it and we do that when we
format network storage paths for gluster for example. Even though
virStorageSourceParseBackingURI() uses virURIParse(), it throws that data
structure right away.
Since we want to format URIs as URIs and not absolute URIs or opaque
URIs (see RFC 3986), we can specify that with a special hack thanks to
commit beb7281055dbf0ed4d041022a67c6c5cfd126f25, by setting port to -1.
This fixes qemuxml2argvtest test where the disk-drive-network-gluster
case was failing.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
(cherry picked from commit 8f17d0eaae7ee2fa3e214b79b188fc14ed5aa1eb)
In systemd >= 218, the udev_set_log_fn method has been marked
deprecated and turned into a no-op. Nothing in the udev client
library will print to stderr by default anymore, so we can
just stop installing a logging hook for new enough udev.
(cherry picked from commit a93a3b975cd0bad37ccae508d9b7a69aa72b6181)
The call to virDomainSnapshotRedefinePrep() had a spurrious ! in front of
it which caused Coverity to complan that the expression is always false.
(cherry picked from commit 9d7254de430f7ef7a4c6a2a20718942369ce9d06)
Well, in 8ad126e6 we tried to fix a memory corruption problem.
However, the fix was not as good as it could be. I mean, the
commit has one line more than it should. I've noticed this output
just recently:
# ./run valgrind --leak-check=full --show-reachable=yes ./tools/virsh domblklist gentoo
==17019== Memcheck, a memory error detector
==17019== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==17019== Using Valgrind-3.10.1 and LibVEX; rerun with -h for copyright info
==17019== Command: /home/zippy/work/libvirt/libvirt.git/tools/.libs/virsh domblklist gentoo
==17019==
Target Source
------------------------------------------------
fda /var/lib/libvirt/images/fd.img
vda /var/lib/libvirt/images/gentoo.qcow2
hdc /home/zippy/tmp/install-amd64-minimal-20150402.iso
==17019== Thread 2:
==17019== Invalid read of size 4
==17019== at 0x4EFF5B4: virObjectUnref (virobject.c:258)
==17019== by 0x5038CFF: remoteClientCloseFunc (remote_driver.c:552)
==17019== by 0x5069D57: virNetClientCloseLocked (virnetclient.c:685)
==17019== by 0x506C848: virNetClientIncomingEvent (virnetclient.c:1852)
==17019== by 0x5082136: virNetSocketEventHandle (virnetsocket.c:1913)
==17019== by 0x4ECD64E: virEventPollDispatchHandles (vireventpoll.c:509)
==17019== by 0x4ECDE02: virEventPollRunOnce (vireventpoll.c:658)
==17019== by 0x4ECBF00: virEventRunDefaultImpl (virevent.c:308)
==17019== by 0x130386: vshEventLoop (vsh.c:1864)
==17019== by 0x4F1EB07: virThreadHelper (virthread.c:206)
==17019== by 0xA8462D3: start_thread (in /lib64/libpthread-2.20.so)
==17019== by 0xAB441FC: clone (in /lib64/libc-2.20.so)
==17019== Address 0x139023f4 is 4 bytes inside a block of size 240 free'd
==17019== at 0x4C2B1F0: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==17019== by 0x4EA8949: virFree (viralloc.c:582)
==17019== by 0x4EFF6D0: virObjectUnref (virobject.c:273)
==17019== by 0x4FE74D6: virConnectClose (libvirt.c:1390)
==17019== by 0x13342A: virshDeinit (virsh.c:406)
==17019== by 0x134A37: main (virsh.c:950)
The problem is, when registering remoteClientCloseFunc(), it's
conn->closeCallback which is ref'd. But in the function itself
it's conn->closeCallback->conn what is unref'd. This is causing
imbalance in reference counting. Moreover, there's no need for
the remote driver to increase/decrease conn refcount since it's
not used anywhere. It's just merely passed to client registered
callback. And for that purpose it's correctly ref'd in
virConnectRegisterCloseCallback() and then unref'd in
virConnectUnregisterCloseCallback().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit e68930077034f786e219bdb015f8880dbc5a246f)
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The function is called from all {Attach,Update,Detach}Device APIs to
create config strings that are later passed to the xend to perform the
desired action. The function is intended to handle all supported
devices. However, as of 5b05358abacb1029fa0d61f72decacf0d4fd8ffb we
are trying to get disk driver of the device without checking if the
device really is a disk. This leads to an segmentation fault:
#0 0x00007ffff7571815 in virDomainDiskGetDriver () from /usr/lib/libvirt.so.0
#1 0x00007fffeb9ad471 in ?? () from /usr/lib/libvirt/connection-driver/libvirt_driver_xen.so
#2 0x00007fffeb9b1062 in xenDaemonAttachDeviceFlags () from /usr/lib/libvirt/connection-driver/libvirt_driver_xen.so
#3 0x00007fffeb9a8a86 in ?? () from /usr/lib/libvirt/connection-driver/libvirt_driver_xen.so
#4 0x00007ffff7609266 in virDomainAttachDevice () from /usr/lib/libvirt.so.0
#5 0x0000555555593c9d in ?? ()
#6 0x00007ffff76743c9 in virNetServerProgramDispatch () from /usr/lib/libvirt.so.0
#7 0x00005555555a678d in ?? ()
#8 0x00007ffff755460e in ?? () from /usr/lib/libvirt.so.0
#9 0x00007ffff7553b06 in ?? () from /usr/lib/libvirt.so.0
#10 0x00007ffff4998b50 in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0
#11 0x00007ffff46e30ed in clone () from /lib/x86_64-linux-gnu/libc.so.6
#12 0x0000000000000000 in ?? ()
Reported-by: Xiaolin Su <linxxnil@126.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit cd7702d4561bc100f291be7a1f6fa8f358440558)
The ACL check didn't check the VIR_DOMAIN_XML_SECURE flag and the
appropriate permission for it. Found via code inspection while fixing
permissions for save images.
(cherry picked from commit b347c0c2a321ec5c20aae214927949832a288c5a)
The ACL check didn't check the VIR_DOMAIN_XML_SECURE flag and the
appropriate permission for it.
(cherry picked from commit 03c3c0c874c84dfa51ef17556062b095c6e1c0a3)
https://bugs.gentoo.org/show_bug.cgi?id=508336
At wireshark, they have this promise to change public dissector APIs
only with minor version number change. Which they did when releasing
the version of 1.12.
Firstly, they've changed tvb_memdup() in
a0c53ffaa1bb46d8c9db2ec739401aa411c9790e so now it takes four arguments
instead of three. The new argument is placed at the very beginning of
the list of arguments and basically says the scope where we'd like to
allocate the memory. According to the documentation NULL should be the
default value.
Then, the tcp_dissect_pdus() signature changed too. Well, the function
that actually dissects reassembled packets as tcp_dissect_pdus()
reorder TCP packets into one big chunk and then calls a user function
to dissect the PDU at once. The change is dated back to
8081cf1d90397cbbb4404f9720595e1537ed5e14.
Then, WS_DLL_PUBLIC_NOEXTERN was replaced with WS_DLL_PUBLIC_DEF in
5d87a8c46171f572568db5a47c093423482e342f.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit e74fa5702a238b2e8e42f84bba78e9beab9c28b3)
The rationale is to not duplicate code which is done in
packet-libvirt.h for instance. Moreover, this way we can drop
__attribute_((unused)) used int packet-libvirt.c in favor of
ATTRIBUTE_UNUSED.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 906d0abfe720991a4a1b5e6de8a24a5c6946c009)
Avoid leaving the domain locked on a failed ACL check in
qemuDomainMigratePerform() and qemuDomainMigrateFinish2().
Introduced in commit abf75aea247e (Add ACL checks into the QEMU driver).
(cherry picked from commit 2bdcd29c713dfedd813c89f56ae98f6f3898313d)
virNetDevLinkDump() gets a message from netlink into "resp", then
calls nlmsg_parse() to fill the table "tb" with pointers into resp. It
then returns tb to its caller, but not before freeing the buffer at
resp. That means that all the callers of virNetDevLinkDump() are
examining memory that has already been freed. This can be verified by
filling the buffer at resp with garbage prior to freeing it (or, I
suppose, just running libvirtd under valgrind) then performing some
operation that calls virNetDevLinkDump().
The upstream commit log incorrectly states that the code has been like
this ever since virNetDevLinkDump() was written. In reality, the
problem was introduced with commit e95de74d, first in libvirt-1.0.5,
which was attempting to eliminate a typecast that caused compiler
warnings. It has only been pure luck (or maybe a lack of heavy load,
and/or maybe an allocation algorithm in malloc() that delays re-use of
just-freed memory) that has kept this from causing errors, for example
when configuring a PCI passthrough or macvtap passthrough network
interface.
The solution taken in this patch is the simplest - just return resp to
the caller along with tb, then have the caller free it after they are
finished using the data (pointers) in tb. I alternately could have
made a cleaner interface by creating a new struct that put tb and resp
together along with a vir*Free() function for it, but this function is
only used in a couple places, and I'm not sure there will be
additional new uses of virNetDevLinkDump(), so the value of adding a
new type, extra APIs, etc. is dubious.
(cherry picked from commit f9f9699f40729556238b905f67a7d6f68c084f6a)
Commit 28f8dfd (v1.0.0) introduced a security hole: in at least
the qemu implementation of virDomainGetXMLDesc, the use of the
flag VIR_DOMAIN_XML_MIGRATABLE (which is usable from a read-only
connection) triggers the implicit use of VIR_DOMAIN_XML_SECURE
prior to calling qemuDomainFormatXML. However, the use of
VIR_DOMAIN_XML_SECURE is supposed to be restricted to read-write
clients only. This patch treats the migratable flag as requiring
the same permissions, rather than analyzing what might break if
migratable xml no longer includes secret information.
Fortunately, the information leak is low-risk: all that is gated
by the VIR_DOMAIN_XML_SECURE flag is the VNC connection password;
but VNC passwords are already weak (FIPS forbids their use, and
on a non-FIPS machine, anyone stupid enough to trust a max-8-byte
password sent in plaintext over the network deserves what they
get). SPICE offers better security than VNC, and all other
secrets are properly protected by use of virSecret associations
rather than direct output in domain XML.
* src/remote/remote_protocol.x (REMOTE_PROC_DOMAIN_GET_XML_DESC):
Tighten rules on use of migratable flag.
* src/libvirt-domain.c (virDomainGetXMLDesc): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit b1674ad5a97441b7e1bd5f5ebaff498ef2fbb11b)
Conflicts:
src/libvirt-domain.c - file split from older src/libvirt.c
Signed-off-by: Eric Blake <eblake@redhat.com>
If you use public api virConnectListAllDomains() with second parameter
set to NULL to get only the number of domains you will lock out all
other operations with domains.
Introduced by commit 2c680804.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
(cherry picked from commit fc22b2e74890873848b43fffae43025d22053669)
Live definition was used to look up the disk index while persistent one
was indexed leading to a crash in qemuDomainGetBlockIoTune. Use the
correct def and report a nice error.
Unfortunately it's accessible via read-only connection, though it can
only crash libvirtd in the cases where the guest is hot-plugging disks
without reflecting those changes to the persistent definition. So
avoiding hotplug, or doing hotplug where persistent is always modified
alongside live definition, will avoid the out-of-bounds access.
Introduced in: eca96694a7f992be633d48d5ca03cedc9bbc3c9aa (v0.9.8)
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1140724
Reported-by: Luyao Huang <lhuang@redhat.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
(cherry picked from commit 3e745e8f775dfe6f64f18b5c2fe4791b35d3546b)
Commit 65d8c92a fixed the mingw spec file for 32-bit builds,
but forgot to make the adjustment for 64-bit builds:
Checking for unpackaged file(s): /usr/lib/rpm/check-files /home/eblake/rpmbuild/BUILDROOT/mingw-libvirt-1.2.7-1.fc20.eblake1404944503.x86_64
error: Installed (but unpackaged) file(s) found:
/usr/x86_64-w64-mingw32/sys-root/mingw/lib/pkgconfig/libvirt-lxc.pc
/usr/x86_64-w64-mingw32/sys-root/mingw/lib/pkgconfig/libvirt-qemu.pc
* mingw-libvirt.spec.in (%files): List missing .pc files.
Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit ddf6b139cfebee4193bf6f0b13c995a182d7bc35)
We have the following matrix of possible arguments handled by the logic
statement touched by this patch:
| flags & _REUSE_EXT | !(flags & _REUSE_EXT)
-------+--------------------+----------------------
format| (1) | (2)
-------+--------------------+----------------------
!format| (3) | (4)
-------+--------------------+----------------------
In cases 1 and 2 the user provided a format, in cases 3 and 4 not. The
user requests to use a pre-existing image in 1 and 3 and libvirt will
create a new image in 2 and 4.
The difference between cases 3 and 4 is that for 3 the format is probed
from the user-provided image, whereas in 4 we just use the existing disk
format.
The current code would treat cases 1,3 and 4 correctly but in case 2 the
format provided by the user would be ignored.
The particular piece of code was broken in commit 35c7701c64508f975dfeb8
but since it was introduced a few commits before that it was never
released as working.
Since there is code using functions from the libxml library,
libvirt_conf should have that in LIBADD so it can be linked against
even without libvirt_util (which usually deals with the error itself,
since libvirt_util has libxml in LIBADD). The same applies to
storage_backend.c.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
In the test, the snapshot XML is written into a file that's located
under:
abs_srcdir/vboxsnapshotxmldata/testResult.vbox
However, the abs_srcdir doesn't have to be necessarily writable. It
should have been abs_builddir instead. Moreover, the label in the func
creating the file is called 'fail' while it fulfils the duty of
'cleanup' label.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
At the very beginning of the test we check if the underlying
filesystem supports extended attributes as they are used to store fake
SELinux labels. In order to check that, a dummy file is created and
semi-random attribute is set. However, the file is created under:
abs_srcdir "/securityselinuxlabeldata/testxattr"
which has two problems: abs_srcdir is not required to be writable, so
it should have been abs_builddir. The second one is - there's no
"securityselinuxlabeldata" folder under abs_builddir. The problem was
introduced in caf164f1.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
virFileReadAll already logs an error. If reading the 'speed' file
fails with EINVAL, we log an error even though we ignore it. If it
fails with other errors, we log two errors.
Use virFileReadAllQuiet - ignore EINVAL and report just one error
in other cases.
Fixes this error on libvirtd startup:
2014-06-30 12:47:14.583+0000: 20971: error : virFileReadAll:1297 :
Failed to read file '/sys/class/net/wlan0/speed': Invalid argument
This stops the error message spam when running unprivileged
libvirtd:
2014-06-30 12:38:47.990+0000: 631: error : virPCIDeviceConfigOpen:300 :
Failed to open config space file
'/sys/bus/pci/devices/0000:00:00.0/config': Permission denied
Reported by Daniel Berrange:
https://www.redhat.com/archives/libvir-list/2014-June/msg01082.html
Xen PV domains always have a PV console, so add one to the domain
config via post-parse callback if not explicitly specified in
the XML. The legacy Xen driver behaves similarly, causing a
regression when switching to the new Xen toolstack. I.e.
virsh console pv-domain
will no longer work after upgrading a xm/xend stack to xl/libxl.
Noticed the following error when building the vbox driver
in the openSUSE build service
CCLD vboxsnapshotxmltest
/usr/lib64/gcc/x86_64-suse-linux/4.8/../../../../x86_64-suse-linux/bin/ld:
../src/.libs/libvirt_driver_vbox_impl.a
(libvirt_driver_vbox_impl_la-vbox_snapshot_conf.o):
undefined reference to symbol 'xmlXPathRegisterNs@@LIBXML2_2.4.30'
/usr/lib64/libxml2.so: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
Fixed by adding LIBXML_LIBS to libvirt_driver_vbox_impl_la_LIBADD
libxl interface for vcpu pinning is changing in Xen 4.5. Basically,
libxl_set_vcpuaffinity() now wants one more parameter. That is
representative of 'VCPU soft affinity', which libvirt does not use.
To mark such change, the macro LIBXL_HAVE_VCPUINFO_SOFT_AFFINITY is
defined. Use it as a gate and, if present, re-#define the calls from
the old to the new interface, to avoid breaking the build.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Jim Fehlig <jfehlig@suse.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Throwing an error is much friendly than just
"error: An error occurred, but the cause is unknown"
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Commit 55bbb011b965c7962933604c70f61cef45e8ec04 introduced a regression
where we forgot to save the persistent domain configuration after an
external snapshot. This would make libvirt forget the snapshots and
effectively revert to the previous state in the following scenario:
1) Start VM
2) Take snapshot
3) Destroy VM
4) Restart libvirtd
Also fix spurious blank line added by patch mentioned above.
Instead of maintaining two very similar APIs, add the "@mac" parameter
to virNetworkGetDHCPLeases and kill virNetworkGetDHCPLeasesForMAC. Both
of those functions would return data the same way, so making @mac an
optional filter simplifies a lot of stuff.
libvirt unit test used setxattr with "user.libvirt.selinux" name to
emulate setfilecon of selinux. But for some old kernel filesystem
(like 2.6.32-431.el6.x86_64), if the filesystem is not mounted with
user_xattr flag, the setxattr with "user.libvirt.selinux" will fail.
So adding testUserXattrEnabled() in securityselinuxlabeltest.c,
if user_xattr is not enabled, skip this case.
The user_xattr is departed in newer kernel, therefore this commit is
only for the compatablity for old kernel.
Signed-off-by: Jincheng Miao <jmiao@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Tested-by: Scott Sullivan <ssullivan@liquidweb.com>
We publish libvirt-api.xml for others to use, and in fact, the
libvirt-python bindings use it to generate python constants that
correspond to our enum values. However, we had an off-by-one bug
that any enum that relied on C's rules for implicit initialization
of the first enum member to 0 got listed in the xml as having a
value of 1 (and all later members of the enum were equally
botched).
The fix is simple - since we add one to the previous value when
encountering an enum without an initializer, the previous value
must start at -1 so that the first enum member is assigned 0.
The python generator code has had the off-by-one ever since DV
first wrote it years ago, but most of our public enums were immune
because they had an explicit = 0 initializer. The only affected
enums are:
- virDomainEventGraphicsAddressType (such as
VIR_DOMAIN_EVENT_GRAPHICS_ADDRESS_IPV4), since commit 987e31e
(libvirt v0.8.0)
- virDomainCoreDumpFormat (such as VIR_DOMAIN_CORE_DUMP_FORMAT_RAW),
since commit 9fbaff0 (libvirt v1.2.3)
- virIPAddrType (such as VIR_IP_ADDR_TYPE_IPV4), since commit
03e0e79 (not yet released)
Thanks to Nehal J Wani for reporting the problem on IRC, and
for helping me zero in on the culprit function.
* docs/apibuild.py (CParser.parseEnumBlock): Fix implicit enum
values.
Signed-off-by: Eric Blake <eblake@redhat.com>
libxl does not support save, restore, or migrate on all architectures,
notably ARM. Detect whether libxl supports these operations using
LIBXL_HAVE_NO_SUSPEND_RESUME. If not supported, drop advertisement of
<migration_features>.
Found by Ian Campbell while improving Xen's OSSTEST infrastructure
http://lists.xen.org/archives/html/xen-devel/2014-06/msg02171.html
Since commit d86c876a66e320b55220d00113027c9ad6199cff we are using
guestfwd=tcp:IP:PORT,chardev=ID for guestfwd specification, however,
that has not changed in qemu, so guestfwd does not work since.
Apart from that, guestfwd is not working with older qemu that doesn't
have QEMU_CAPS_DEVICE.
Both regressions exist since late 2009 and nobody found that (until
now), so I'm only fixing the first one.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1112066
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Allow people to build external bindings using the 'run' script
by defining the PKG_CONFIG_PATH var in it. eg to build Python
you could do
../libvirt/run python setup.py build
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The QEMU VNC client arg code has a long standing typo
of SASL_CONF_DIR when it should be SASL_CONF_PATH for
the env variable name.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When creating a new disk mirror the new struct is stored in a separate
variable until everything went well. The removed hunk would actually
remove existing mirror information for example when the api would be run
if a mirror still exists.
The function headers contain type on the same line as the name. When
combined with usage of ATTRIBUTE_UNUSED, the function headers were very
long. Shorten them by breaking the line after the type.
virSecurityManagerSetDiskLabel and virSecurityManagerRestoreDiskLabel
don't have complementary semantics. Document the semantics to avoid
possible problems.
