14092 Commits

Author SHA1 Message Date
Laine Stump
cac0038a19 util: eliminate "use after free" in callers of virNetDevLinkDump
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)

Conflicts:
	src/util/virnetdevvportprofile.c - whitespace/copyright change
2014-11-13 12:27:48 -05:00
Eric Blake
f8c7713359 CVE-2014-7823: dumpxml: security hole with migratable flag
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; context with older virLibConnError
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-11-10 08:05:15 -07:00
Pavel Hrdina
64c04d03ce domain_conf: fix domain deadlock
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)
2014-10-01 11:42:10 -06:00
Peter Krempa
ed071fee07 CVE-2014-3633: qemu: blkiotune: Use correct definition when looking up disk
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)
2014-09-17 21:05:15 -06:00
Peter Krempa
9bb60cb443 qemu: copy: Accept 'format' parameter when copying to a non-existing img
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.

(cherry picked from commit 42619ed05d7924978f3e6e2399522fc6f30607de)
Signed-off-by: Eric Blake <eblake@redhat.com>

Conflicts:
	src/qemu/qemu_driver.c - no refactoring of commits 7b7bf001, 4f20226
2014-07-02 21:56:00 -06:00
Eric Blake
cc4160e75d build: fix 'make check' with newer git
Newer git doesn't like the maint.mk rule 'public-submodule-commit'
run during 'make check', as inherited from our checkout of gnulib.
I tracked down that libvirt commit 8531301 picked up a gnulib fix
that makes git happy.  Rather than try and do a full .gnulib
submodule update to gnulib.git d18d1b802 (as used in that libvirt
commit), it was easier to just backport the fixed maint.mk from
gnulib on top of our existing submodule level.  I did it as follows,
where these steps will have to be repeated when cherry-picking this
commit to any other maintenance branch:

mkdir -p gnulib/local/top
cd .gnulib
git checkout d18d1b802 top/maint.mk
git diff HEAD > ../gnulib/local/top/maint.mk.diff
git reset --hard
cd ..
git add gnulib/local/top

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-07-02 21:52:22 -06:00
Eric Blake
de00f27186 docs: publish correct enum values
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>
(cherry picked from commit 9b291bbe20c36c0820c6e7cd2bf6229bf41807e8)

Conflicts:
	docs/apibuild.py - context with 2a40951
2014-06-26 16:49:56 -06:00
Peter Krempa
f527b2253e qemu: blockcopy: Don't remove existing disk mirror info
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.

(cherry picked from commit 02b364e186d487f54ed410c01af042f23e812d42)

This fixes a regression introduced in commit ff5f30b.

Signed-off-by: Eric Blake <eblake@redhat.com>

Conflicts:
	src/qemu/qemu_driver.c - no refactoring of commits 7b7bf001, 4f20226
2014-06-26 16:48:32 -06:00
Daniel P. Berrange
cfc94140e5 LSN-2014-0003: Don't expand entities when parsing XML
If the XML_PARSE_NOENT flag is passed to libxml2, then any
entities in the input document will be fully expanded. This
allows the user to read arbitrary files on the host machine
by creating an entity pointing to a local file. Removing
the XML_PARSE_NOENT flag means that any entities are left
unchanged by the parser, or expanded to "" by the XPath
APIs.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit d6b27d3e4c40946efa79e91d134616b41b1666c4)
2014-05-06 14:33:57 +01:00
Laine Stump
062673a97f qemu: fix crash when removing <filterref> from interface with update-device
If a domain network interface that contains a <filterref> is modified
"live" using "virsh update-device --live", libvirtd would crash. This
was because the code supporting live update of an interface's
filterref was assuming that a filterref might be added or modified,
but didn't account for removing the filterref, resulting in a null
dereference of the filter name.

Introduced with commit 258fb278, which was first in libvirt v1.0.1.

This addresses https://bugzilla.redhat.com/show_bug.cgi?id=1093301

(cherry picked from commit 0eac9d1e90fc3388030c6109aeb1f4860f108054)
2014-05-01 16:27:53 +03:00
Martin Kletzander
fb285a9dc2 qemu: make sure agent returns error when required data are missing
Commit 5b3492fa aimed to fix this and caught one error but exposed
another one.  When agent command is being executed and the thread
waiting for the reply is woken up by an event (e.g. EOF in case of
shutdown), the command finishes with no data (rxObject == NULL), but
no error is reported, since this might be desired by the caller
(e.g. suspend through agent).  However, in other situations, when the
data are required (e.g. getting vCPUs), we proceed to getting desired
data out of the reply, but none of the virJSON*() functions works well
with NULLs.  I chose the way of a new parameter for qemuAgentCommand()
function that specifies whether reply is required and behaves
according to that.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1058149

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
(cherry picked from commit 736e017e3608ce4c97ee519a293ff7faecea040d)
2014-04-09 18:29:10 +02:00
Martin Kletzander
d9af0809b0 qemu: remove unneeded forward declaration
by moving qemuAgentCommand() after qemuAgentCheckError().

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
(cherry picked from commit e9d09fe19680fcb1810774023aa5c2ef007b10c6)

Conflicts:
        src/qemu/qemu_agent.c -- label indentation (5922d05a)
                                 comment removal (56874f01)
2014-04-09 18:29:04 +02:00
Martin Kletzander
49e60cca08 qemu: cleanup error checking on agent replies
On all the places where qemuAgentComand() was called, we did a check
for errors in the reply.  Unfortunately, some of the places called
qemuAgentCheckError() without checking for non-null reply which might
have resulted in a crash.

So this patch makes the error-checking part of qemuAgentCommand()
itself, which:

 a) makes it look better,

 b) makes the check mandatory and, most importantly,

 c) checks for the errors if and only if it is appropriate.

This actually fixes a potential crashers when qemuAgentComand()
returned 0, but reply was NULL.  Having said that, it *should* fix the
following bug:

https://bugzilla.redhat.com/show_bug.cgi?id=1058149

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
(cherry picked from commit 5b3492fadb6bfddd370e263bf8a6953b1b26116f)
2014-04-09 18:28:47 +02:00
Michal Privoznik
3bec3cdbf2 virNetClientSetTLSSession: Restore original signal mask
Currently, we use pthread_sigmask(SIG_BLOCK, ...) prior to calling
poll(). This is okay, as we don't want poll() to be interrupted.
However, then - immediately as we fall out from the poll() - we try to
restore the original sigmask - again using SIG_BLOCK. But as the man
page says, SIG_BLOCK adds signals to the signal mask:

SIG_BLOCK
      The set of blocked signals is the union of the current set and the set argument.

Therefore, when restoring the original mask, we need to completely
overwrite the one we set earlier and hence we should be using:

SIG_SETMASK
      The set of blocked signals is set to the argument set.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 3d4b4f5ac634c123af1981084add29d3a2ca6ab0)
2014-03-19 16:41:08 -06:00
Daniel P. Berrange
7ad2a25f97 Add a mutex to serialize updates to firewall
The nwfilter conf update mutex previously serialized
updates to the internal data structures for firewall
rules, and updates to the firewall itself. The latter
was recently turned into a read/write lock, and filter
instantiation allowed to proceed in parallel. It was
believed that this was ok, since each filter is created
on a separate iptables/ebtables chain.

It turns out that there is a subtle lock ordering problem
on virNWFilterObjPtr instances. __virNWFilterInstantiateFilter
will hold a lock on the virNWFilterObjPtr it is instantiating.
This in turn invokes virNWFilterInstantiate which then invokes
virNWFilterDetermineMissingVarsRec which then invokes
virNWFilterObjFindByName. This iterates over every single
virNWFilterObjPtr in the list, locking them and checking their
name. So if 2 or more threads try to instantiate a filter in
parallel, they'll all hold 1 lock at the top level in the
__virNWFilterInstantiateFilter method which will cause the
other thread to deadlock in virNWFilterObjFindByName.

The fix is to add an exclusive mutex to serialize the
execution of __virNWFilterInstantiateFilter.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 925de19ed7f13e0d12d0b993496d314bab886589)
2014-03-10 12:29:44 +00:00
Daniel P. Berrange
6ecb7bc3ae CVE-2013-6456: Avoid unsafe use of /proc/$PID/root in LXC hotunplug code
Rewrite multiple hotunplug functions to to use the
virProcessRunInMountNamespace helper. This avoids
risk of a malicious guest replacing /dev with an absolute
symlink, tricking the driver into changing the host OS
filesystem.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 5fc590ad9f4071350a8df4d567ba88baacc8334d)
2014-02-18 15:52:23 +00:00
Daniel P. Berrange
72a4c29ca7 CVE-2013-6456: Avoid unsafe use of /proc/$PID/root in LXC chardev hostdev hotplug
Rewrite lxcDomainAttachDeviceHostdevMiscLive function
to use the virProcessRunInMountNamespace helper. This avoids
risk of a malicious guest replacing /dev with a absolute
symlink, tricking the driver into changing the host OS
filesystem.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 1cadeafcaa422844a27ef622e2a7041d0235bcb3)
2014-02-18 15:52:23 +00:00
Daniel P. Berrange
83f83508e1 CVE-2013-6456: Avoid unsafe use of /proc/$PID/root in LXC block hostdev hotplug
Rewrite lxcDomainAttachDeviceHostdevStorageLive function
to use the virProcessRunInMountNamespace helper. This avoids
risk of a malicious guest replacing /dev with a absolute
symlink, tricking the driver into changing the host OS
filesystem.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 1754c7f0ab1407dcf7c89636a35711dd9b1febe1)
2014-02-18 15:52:23 +00:00
Daniel P. Berrange
398c88edfa CVE-2013-6456: Avoid unsafe use of /proc/$PID/root in LXC USB hotplug
Rewrite lxcDomainAttachDeviceHostdevSubsysUSBLive function
to use the virProcessRunInMountNamespace helper. This avoids
risk of a malicious guest replacing /dev with a absolute
symlink, tricking the driver into changing the host OS
filesystem.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 7fba01c15c1f886b4235825692b4c13e88dd9f7b)
2014-02-18 15:52:23 +00:00
Daniel P. Berrange
dd055960df CVE-2013-6456: Avoid unsafe use of /proc/$PID/root in LXC disk hotplug
Rewrite lxcDomainAttachDeviceDiskLive function to use the
virProcessRunInMountNamespace helper. This avoids risk of
a malicious guest replacing /dev with a absolute symlink,
tricking the driver into changing the host OS filesystem.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 4dd3a7d5bc44980135a1b11810ba9aeab42a4a59)
2014-02-18 15:52:23 +00:00
Eric Blake
14d69bd00e CVE-2013-6456: Avoid unsafe use of /proc/$PID/root in LXC shutdown/reboot code
Use helper virProcessRunInMountNamespace in lxcDomainShutdownFlags and
lxcDomainReboot.  Otherwise, a malicious guest could use symlinks
to force the host to manipulate the wrong file in the host's namespace.

Idea by Dan Berrange, based on an initial report by Reco
<recoverym4n@gmail.com> at
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=732394

Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit aebbcdd33c8c18891f0bdbbf8924599a28152c9c)
2014-02-18 15:52:23 +00:00
Daniel P. Berrange
05b3616217 Add helper for running code in separate namespaces
Implement virProcessRunInMountNamespace, which runs callback of type
virProcessNamespaceCallback in a container namespace. This uses a
child process to run the callback, since you can't change the mount
namespace of a thread. This implies that callbacks have to be careful
about what code they run due to async safety rules.

Idea by Dan Berrange, based on an initial report by Reco
<recoverym4n@gmail.com> at
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=732394

Signed-off-by: Daniel Berrange <berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 7c72ef6f555f1f9844d51be2f38f078bc908652c)
2014-02-18 15:52:23 +00:00
Daniel P. Berrange
599be6a6f9 Add virFileMakeParentPath helper function
Add a helper function which takes a file path and ensures
that all directory components leading up to the file exist.
IOW, it strips the filename part of the path and passes
the result to virFileMakePath.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit c321bfc5c37c603af349dacf531bb03c91b0755e)
2014-02-18 15:52:22 +00:00
Daniel P. Berrange
40c8a8e926 Move check for cgroup devices ACL upfront in LXC hotplug
The check for whether the cgroup devices ACL is available is
done quite late during LXC hotplug - in fact after the device
node is already created in the container in some cases. Better
to do it upfront so we fail immediately.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit c3eb12cace868884393d35c23278653634d81c70)
2014-02-18 15:52:22 +00:00
Daniel P. Berrange
06a0f6b81c Disks are always block devices, never character devices
The LXC disk hotplug code was allowing block or character devices
to be given as disk. A disk is always a block device.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit d24e6b8b1eb87daa6ee467b76cf343725468949c)
2014-02-18 15:52:22 +00:00
Daniel P. Berrange
045ab83be8 Fix reset of cgroup when detaching USB device from LXC guests
When detaching a USB device from an LXC guest we must remove
the device from the cgroup ACL. Unfortunately we were telling
the cgroup code to use the guest /dev path, not the host /dev
path, and the guest device node had already been unlinked.
This was, however, fortunate since the code passed &priv->cgroup
instead of priv->cgroup, so would have crash if the device node
were accessible.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 2c2bec94d27ccd070bee18a6113b1cfea6d80126)
2014-02-18 15:52:22 +00:00
Daniel P. Berrange
869961c1a2 Record hotplugged USB device in LXC live guest config
After hotplugging a USB device, the LXC driver forgot
to add the device def to the virDomainDefPtr.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit a537827d15516f2b59afb23ce2d50b8a88d7f090)
2014-02-18 15:52:22 +00:00
Daniel P. Berrange
d0ddd54a67 Fix path used for USB device attach with LXC
The LXC code missed the 'usb' component out of the path
/dev/bus/usb/$BUSNUM/$DEVNUM, so it failed to actually
setup cgroups for the device. This was in fact lucky
because the call to virLXCSetupHostUsbDeviceCgroup
was also mistakenly passing '&priv->cgroup' instead of
just 'priv->cgroup'. So once the path is fixed, libvirtd
would then crash trying to access the bogus virCgroupPtr
pointer. This would have been a security issue, were it
not for the bogus path preventing the pointer reference
being reached.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit c3648972222d4eb056e6e667c193ba56a7aa3557)
2014-02-18 15:52:22 +00:00
Daniel P. Berrange
4428224e0d Don't block use of USB with containers
virDomainDefCompatibleDevice blocks use of USB if no USB
controller is present. This is not correct for containers
since devices can be assigned directly regardless of any
controllers.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 7a44af963ef75c487f874bc91613ad45e5b167e9)
2014-02-18 15:52:22 +00:00
Eric Blake
aaba652d2b storage: avoid short reads while chasing backing chain
Our backing file chain code was not very robust to an ill-timed
EINTR, which could lead to a short read causing us to randomly
treat metadata differently than usual.  But the existing
virFileReadLimFD forces an error if we don't read the entire
file, even though we only care about the header of the file.
So add a new virFile function that does what we want.

* src/util/virfile.h (virFileReadHeaderFD): New prototype.
* src/util/virfile.c (virFileReadHeaderFD): New function.
* src/libvirt_private.syms (virfile.h): Export it.
* src/util/virstoragefile.c (virStorageFileGetMetadataInternal)
(virStorageFileProbeFormatFromFD): Use it.

Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 5327fad4f292e4f3f84884ffe158c492bf00519c)

Conflicts:
	src/util/virstoragefile.c: buffer signedness
2014-02-18 15:52:22 +00:00
Eric Blake
5daffc54b0 maint: fix comment typos
* src/lxc/lxc_controller.c (virLXCControllerSetupDisk): Fix typo.
* src/lxc/lxc_driver.c (lxcDomainAttachDeviceDiskLive): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 8de47efd3fdb27d99bc457cc4163d7b5f8595268)
2014-02-18 13:55:55 +00:00
Chen Hanxiao
268ef38d12 LXC: free dst before lxcDomainAttachDeviceDiskLive returns
Free dst before lxcDomainAttachDeviceDiskLive returns

Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
(cherry picked from commit c82513acc2e1e0b035e5e53577a34fd68a530788)
2014-02-18 13:55:55 +00:00
Hongwei Bi
a15d9aa37e LXC: Free variable vroot in lxcDomainDetachDeviceHostdevUSBLive()
The variable vroot should be freed in label cleanup.

(cherry picked from commit 46c9bce4c8b0f2222cc50587ac968ced06eb1eff)
2014-02-18 13:55:55 +00:00
Yuri Chornoivan
25637c4afb Fix minor typos in messages and docs
Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 5b4c035b08c122c3ae15aee7c13ce0f480586502)
2014-02-18 13:55:55 +00:00
Daniel P. Berrange
7440867109 Push nwfilter update locking up to top level
The NWFilter code has as a deadlock race condition between
the virNWFilter{Define,Undefine} APIs and starting of guest
VMs due to mis-matched lock ordering.

In the virNWFilter{Define,Undefine} codepaths the lock ordering
is

  1. nwfilter driver lock
  2. virt driver lock
  3. nwfilter update lock
  4. domain object lock

In the VM guest startup paths the lock ordering is

  1. virt driver lock
  2. domain object lock
  3. nwfilter update lock

As can be seen the domain object and nwfilter update locks are
not acquired in a consistent order.

The fix used is to push the nwfilter update lock upto the top
level resulting in a lock ordering for virNWFilter{Define,Undefine}
of

  1. nwfilter driver lock
  2. nwfilter update lock
  3. virt driver lock
  4. domain object lock

and VM start using

  1. nwfilter update lock
  2. virt driver lock
  3. domain object lock

This has the effect of serializing VM startup once again, even if
no nwfilters are applied to the guest. There is also the possibility
of deadlock due to a call graph loop via virNWFilterInstantiate
and virNWFilterInstantiateFilterLate.

These two problems mean the lock must be turned into a read/write
lock instead of a plain mutex at the same time. The lock is used to
serialize changes to the "driver->nwfilters" hash, so the write lock
only needs to be held by the define/undefine methods. All other
methods can rely on a read lock which allows good concurrency.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 6e5c79a1b5a8b3a23e7df7ffe58fb272aa17fbfb)
2014-02-06 12:55:38 +02:00
Daniel P. Berrange
201eda603b Add a read/write lock implementation
Add virRWLock backed up by a POSIX rwlock primitive

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit c065984b58000a44c90588198d222a314ac532fd)
2014-02-06 12:55:35 +02:00
Daniel P. Berrange
e7e1403e99 Remove use of virConnectPtr from all remaining nwfilter code
The virConnectPtr is passed around loads of nwfilter code in
order to provide it as a parameter to the callback registered
by the virt drivers. None of the virt drivers use this param
though, so it serves no purpose.

Avoiding the need to pass a virConnectPtr means that the
nwfilterStateReload method no longer needs to open a bogus
QEMU driver connection. This addresses a race condition that
can lead to a crash on startup.

The nwfilter driver starts before the QEMU driver and registers
some callbacks with DBus to detect firewalld reload. If the
firewalld reload happens while the QEMU driver is still starting
up though, the nwfilterStateReload method will open a connection
to the partially initialized QEMU driver and cause a crash.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 999d72fbd59ea712128ae294b69b6a54039d757b)
2014-02-06 12:55:31 +02:00
Daniel P. Berrange
86d59eb37d Don't pass virConnectPtr in nwfilter 'struct domUpdateCBStruct'
The nwfilter driver only needs a reference to its private
state object, not a full virConnectPtr. Update the domUpdateCBStruct
struct to have a 'void *opaque' field instead of a virConnectPtr.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit ebca369e3fe5ac999c261c2d44e60a1bac3cfe65)
2014-02-06 12:55:26 +02:00
Daniel P. Berrange
583a69ae2d Remove virConnectPtr arg from virNWFilterDefParse*
None of the virNWFilterDefParse* methods require a virConnectPtr
arg, so just drop it

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit b77b16ce4166dcc87963ae5d279b77b162ddbb55)
2014-02-06 12:55:22 +02:00
Daniel P. Berrange
686408be97 Don't ignore errors parsing nwfilter rules
For inexplicable reasons, the nwfilter XML parser is intentionally
ignoring errors that arise during parsing. As well as meaning that
users don't get any feedback on their XML mistakes, this will lead
it to silently drop data in OOM conditions.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 4f2094346d98f4ed6a2de115d204c166cc563496)
2014-02-06 12:55:17 +02:00
Eric Blake
e46669e966 event: move event filtering to daemon (regression fix)
https://bugzilla.redhat.com/show_bug.cgi?id=1058839

Commit f9f56340 for CVE-2014-0028 almost had the right idea - we
need to check the ACL rules to filter which events to send.  But
it overlooked one thing: the event dispatch queue is running in
the main loop thread, and therefore does not normally have a
current virIdentityPtr.  But filter checks can be based on current
identity, so when libvirtd.conf contains access_drivers=["polkit"],
we ended up rejecting access for EVERY event due to failure to
look up the current identity, even if it should have been allowed.

Furthermore, even for events that are triggered by API calls, it
is important to remember that the point of events is that they can
be copied across multiple connections, which may have separate
identities and permissions.  So even if events were dispatched
from a context where we have an identity, we must change to the
correct identity of the connection that will be receiving the
event, rather than basing a decision on the context that triggered
the event, when deciding whether to filter an event to a
particular connection.

If there were an easy way to get from virConnectPtr to the
appropriate virIdentityPtr, then object_event.c could adjust the
identity prior to checking whether to dispatch an event.  But
setting up that back-reference is a bit invasive.  Instead, it
is easier to delay the filtering check until lower down the
stack, at the point where we have direct access to the RPC
client object that owns an identity.  As such, this patch ends
up reverting a large portion of the framework of commit f9f56340.
We also have to teach 'make check' to special-case the fact that
the event registration filtering is done at the point of dispatch,
rather than the point of registration.  Note that even though we
don't actually use virConnectDomainEventRegisterCheckACL (because
the RegisterAny variant is sufficient), we still generate the
function for the purposes of documenting that the filtering
takes place.

Also note that I did not entirely delete the notion of a filter
from object_event.c; I still plan on using that for my upcoming
patch series for qemu monitor events in libvirt-qemu.so.  In
other words, while this patch changes ACL filtering to live in
remote.c and therefore we have no current client of the filtering
in object_event.c, the notion of filtering in object_event.c is
still useful down the road.

* src/check-aclrules.pl: Exempt event registration from having to
pass checkACL filter down call stack.
* daemon/remote.c (remoteRelayDomainEventCheckACL)
(remoteRelayNetworkEventCheckACL): New functions.
(remoteRelay*Event*): Use new functions.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Drop unused parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/domain_event.c (virDomainEventFilter): Delete unused
function.
* src/conf/network_event.c (virNetworkEventFilter): Likewise.
* src/libxl/libxl_driver.c: Adjust caller.
* src/lxc/lxc_driver.c: Likewise.
* src/network/bridge_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/test/test_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/vbox/vbox_tmpl.c: Likewise.
* src/xen/xen_driver.c: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 11f20e43f1388d5f8f8c0bfac8c9cda6160a106b)

Conflicts:
	daemon/remote.c - not backporting network events
	src/conf/network_event.c - likewise
	src/conf/network_event.h - likewise
	src/network/bridge_driver.c - likewise
	src/conf/domain_event.c - revert back to pre-CVE state
	src/conf/domain_event.h - likewise
	src/libxl/libxl_driver.c - likewise
	src/lxc/lxc_driver.c - likewise
	src/remote/remote_driver.c - likewise
	src/test/test_driver.c - likewise
	src/uml/uml_driver.c - likewise
	src/xen/xen_driver.c - likewise
2014-02-05 09:32:22 -07:00
Eric Blake
1d0e4fbf95 event: filter global events by domain:getattr ACL [CVE-2014-0028]
Ever since ACL filtering was added in commit 7639736 (v1.1.1), a
user could still use event registration to obtain access to a
domain that they could not normally access via virDomainLookup*
or virConnectListAllDomains and friends.  We already have the
framework in the RPC generator for creating the filter, and
previous cleanup patches got us to the point that we can now
wire the filter through the entire object event stack.

Furthermore, whether or not domain:getattr is honored, use of
global events is a form of obtaining a list of networks, which
is covered by connect:search_domains added in a93cd08 (v1.1.0).
Ideally, we'd have a way to enforce connect:search_domains when
doing global registrations while omitting that check on a
per-domain registration.  But this patch just unconditionally
requires connect:search_domains, even when no list could be
obtained, based on the following observations:
1. Administrators are unlikely to grant domain:getattr for one
or all domains while still denying connect:search_domains - a
user that is able to manage domains will want to be able to
manage them efficiently, but efficient management includes being
able to list the domains they can access.  The idea of denying
connect:search_domains while still granting access to individual
domains is therefore not adding any real security, but just
serves as a layer of obscurity to annoy the end user.
2. In the current implementation, domain events are filtered
on the client; the server has no idea if a domain filter was
requested, and must therefore assume that all domain event
requests are global.  Even if we fix the RPC protocol to
allow for server-side filtering for newer client/server combos,
making the connect:serach_domains ACL check conditional on
whether the domain argument was NULL won't benefit older clients.
Therefore, we choose to document that connect:search_domains
is a pre-requisite to any domain event management.

Network events need the same treatment, with the obvious
change of using connect:search_networks and network:getattr.

* src/access/viraccessperm.h
(VIR_ACCESS_PERM_CONNECT_SEARCH_DOMAINS)
(VIR_ACCESS_PERM_CONNECT_SEARCH_NETWORKS): Document additional
effect of the permission.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Add new parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/object_event_private.h (virObjectEventStateRegisterID):
Likewise.
* src/conf/object_event.c (_virObjectEventCallback): Track a filter.
(virObjectEventDispatchMatchCallback): Use filter.
(virObjectEventCallbackListAddID): Register filter.
* src/conf/domain_event.c (virDomainEventFilter): New function.
(virDomainEventStateRegister, virDomainEventStateRegisterID):
Adjust callers.
* src/conf/network_event.c (virNetworkEventFilter): New function.
(virNetworkEventStateRegisterID): Adjust caller.
* src/remote/remote_protocol.x
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_REGISTER)
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_REGISTER_ANY)
(REMOTE_PROC_CONNECT_NETWORK_EVENT_REGISTER_ANY): Generate a
filter, and require connect:search_domains instead of weaker
connect:read.
* src/test/test_driver.c (testConnectDomainEventRegister)
(testConnectDomainEventRegisterAny)
(testConnectNetworkEventRegisterAny): Update callers.
* src/remote/remote_driver.c (remoteConnectDomainEventRegister)
(remoteConnectDomainEventRegisterAny): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectDomainEventRegister)
(xenUnifiedConnectDomainEventRegisterAny): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainGetXMLDesc): Likewise.
* src/libxl/libxl_driver.c (libxlConnectDomainEventRegister)
(libxlConnectDomainEventRegisterAny): Likewise.
* src/qemu/qemu_driver.c (qemuConnectDomainEventRegister)
(qemuConnectDomainEventRegisterAny): Likewise.
* src/uml/uml_driver.c (umlConnectDomainEventRegister)
(umlConnectDomainEventRegisterAny): Likewise.
* src/network/bridge_driver.c
(networkConnectNetworkEventRegisterAny): Likewise.
* src/lxc/lxc_driver.c (lxcConnectDomainEventRegister)
(lxcConnectDomainEventRegisterAny): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit f9f56340539d609cdc2e9d4ab812b9f146c3f100)

Conflicts:
	src/conf/object_event.c - not backporting event refactoring
	src/conf/object_event_private.h - likewise
	src/conf/network_event.c - not backporting network events
	src/conf/network_event.h - likewise
	src/network/bridge_driver.c - likewise
	src/access/viraccessperm.h - likewise
	src/remote/remote_protocol.x - likewise
	src/conf/domain_event.c - includes code that upstream has in object_event
	src/conf/domain_event.h - context
	src/libxl/libxl_driver.c - context
	src/lxc/lxc_driver.c - context
	src/remote/remote_driver.c - context, not backporting network events
	src/test/test_driver.c - context, not backporting network events
	src/uml/uml_driver.c - context
	src/xen/xen_driver.c - context
2014-01-15 14:59:55 -07:00
Eric Blake
a00e4ec96a Fix memory leak in virObjectEventCallbackListRemoveID()
While running objecteventtest, it was found that valgrind pointed out the
following memory leak:

==13464== 5 bytes in 1 blocks are definitely lost in loss record 7 of 134
==13464==    at 0x4A0887C: malloc (vg_replace_malloc.c:270)
==13464==    by 0x341F485E21: strdup (strdup.c:42)
==13464==    by 0x4CAE28F: virStrdup (virstring.c:554)
==13464==    by 0x4CF3CBE: virObjectEventCallbackListAddID (object_event.c:286)
==13464==    by 0x4CF49CA: virObjectEventStateRegisterID (object_event.c:729)
==13464==    by 0x4CF73FE: virDomainEventStateRegisterID (domain_event.c:1424)
==13464==    by 0x4D7358F: testConnectDomainEventRegisterAny (test_driver.c:6032)
==13464==    by 0x4D600C8: virConnectDomainEventRegisterAny (libvirt.c:19128)
==13464==    by 0x402409: testDomainStartStopEvent (objecteventtest.c:232)
==13464==    by 0x403451: virtTestRun (testutils.c:138)
==13464==    by 0x402012: mymain (objecteventtest.c:395)
==13464==    by 0x403AF2: virtTestMain (testutils.c:593)
==13464==

(cherry picked from commit 34d52b3471a18c72b7a02e27d65857505d858a8e)

Conflicts:
	src/conf/object_event.c - 1.2.1 refactoring to object_event not
backported, so change applied directly in older domain_event.c instead
2014-01-15 14:59:54 -07:00
Michal Privoznik
b467dc9f54 virDomainEventCallbackListFree: Don't leak @list->callbacks
The @list->callbacks is an array that is inflated whenever a new event
is added, e.g. via virDomainEventCallbackListAddID(). However, when we
are freeing the array, we free the items within it but forgot to
actually free it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit ea13a759f5b32204e1a7bdf6ee228235acb42bcb)
2014-01-15 14:59:52 -07:00
Jiri Denemark
08672cff7b Really don't crash if a connection closes early
https://bugzilla.redhat.com/show_bug.cgi?id=1047577

When writing commit 173c291, I missed the fact virNetServerClientClose
unlocks the client object before actually clearing client->sock and thus
it is possible to hit a window when client->keepalive is NULL while
client->sock is not NULL. I was thinking client->sock == NULL was a
better check for a closed connection but apparently we have to go with
client->keepalive == NULL to actually fix the crash.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
(cherry picked from commit 066c8ef6c18bc1faf8b3e10787b39796a7a06cc0)
2014-01-15 06:58:05 -07:00
Jiri Denemark
ac4be80261 Don't crash if a connection closes early
https://bugzilla.redhat.com/show_bug.cgi?id=1047577

When a client closes its connection to libvirtd early during
virConnectOpen, more specifically just after making
REMOTE_PROC_CONNECT_SUPPORTS_FEATURE call to check if
VIR_DRV_FEATURE_PROGRAM_KEEPALIVE is supported without even waiting for
the result, libvirtd may crash due to a race in keep-alive
initialization. Once receiving the REMOTE_PROC_CONNECT_SUPPORTS_FEATURE
call, the daemon's event loop delegates it to a worker thread. In case
the event loop detects EOF on the connection and calls
virNetServerClientClose before the worker thread starts to handle
REMOTE_PROC_CONNECT_SUPPORTS_FEATURE call, client->keepalive will be
disposed by the time virNetServerClientStartKeepAlive gets called from
remoteDispatchConnectSupportsFeature. Because the flow is common for
both authenticated and read-only connections, even unprivileged clients
may cause the daemon to crash.

To avoid the crash, virNetServerClientStartKeepAlive needs to check if
the connection is still open before starting keep-alive protocol.

Every libvirt release since 0.9.8 is affected by this bug.

(cherry picked from commit 173c2914734eb5c32df6d35a82bf503e12261bcf)
2014-01-15 06:58:04 -07:00
Jiri Denemark
c5b379e17d qemu: Fix job usage in virDomainGetBlockIoTune
CVE-2013-6458

Every API that is going to begin a job should do that before fetching
data from vm->def.

(cherry picked from commit 3b56425938e2f97208d5918263efa0d6439e4ecd)
2014-01-15 06:58:02 -07:00
Jiri Denemark
51d13311b8 qemu: Fix job usage in qemuDomainBlockCopy
Every API that is going to begin a job should do that before fetching
data from vm->def.

(cherry picked from commit ff5f30b6bfa317f2a4c33f69289baf4e887eb048)
2014-01-15 06:58:01 -07:00
Jiri Denemark
571629b2df qemu: Fix job usage in qemuDomainBlockJobImpl
CVE-2013-6458

Every API that is going to begin a job should do that before fetching
data from vm->def.

(cherry picked from commit f93d2caa070f6197ab50d372d286018b0ba6bbd8)
2014-01-15 06:57:59 -07:00
Jiri Denemark
3451828a28 qemu: Avoid using stale data in virDomainGetBlockInfo
CVE-2013-6458

Generally, every API that is going to begin a job should do that before
fetching data from vm->def. However, qemuDomainGetBlockInfo does not
know whether it will have to start a job or not before checking vm->def.
To avoid using disk alias that might have been freed while we were
waiting for a job, we use its copy. In case the disk was removed in the
meantime, we will fail with "cannot find statistics for device '...'"
error message.

(cherry picked from commit b799259583bd65c0b2f5042e6c3ff19637ade881)
2014-01-15 06:57:58 -07:00