There's a couple reports of things failing in this area (bug 1259070),
but it's tough to tell what's going wrong without stderr from
qemu-bridge-helper. So let's report stderr in the error message

Couple new examples:

virbr0 is inactive:
internal error: /usr/libexec/qemu-bridge-helper --use-vnet --br=virbr0 --fd=21: failed to communicate with bridge helper: Transport endpoint is not connected
stderr=failed to get mtu of bridge `virbr0': No such device

bridge isn't on the ACL:
internal error: /usr/libexec/qemu-bridge-helper --use-vnet --br=br0 --fd=21: failed to communicate with bridge helper: Transport endpoint is not connected
stderr=access denied by acl file

The xenXMConfigCacheRefresh method scans /etc/xen and loads
all config files it finds. It then scans its internal hash
table and purges any (previously) loaded config files whose
refresh timestamp does not match the timestamp recorded at
the start of xenXMConfigCacheRefresh(). There is unfortunately
a subtle flaw in this, because if loading the config files
takes longer than 1 second, some of the config files will
have a refresh timestamp that is 1 or more seconds different
(newer) than is checked for. So we immediately purge a bunch
of valid config files we just loaded.

To avoid this flaw, we must pass the timestamp we record at
the start of xenXMConfigCacheRefresh() into the
xenXMConfigCacheAddFile() method, instead of letting the
latter call time(NULL) again.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

commit 4b53d0d4 "libxl: don't remove persistent domain on start
failure" cleans up the vm object and sets it to NULL if the vm is not
persistent, however at end job vm (now NULL) is dereferenced via the call to
libxlDomainObjEndJob. Avoid this by skipping "endjob" and going
straight to "cleanup" in this case.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>

Up until now, the default has been rtl8139, but no check was in
place to make sure that device was actually available.

Now we try rtl8139, e1000 and virtio-net in turn, checking for
availability before using any of them: this means we have a much
better chance for the guest to be able to boot.

This capability can be used to detect whether or not the QEMU
binary supports the virtio-net-* network device.

This capability can be used to detect whether or not the QEMU
binary supports the e1000 network device.

This capability can be used to detect whether or not the QEMU
binary supports the rtl8139 network device.

Commit f1f68ca3 did not report an error if virFileMakePath()
returned -1.  Well, who would've guessed function with name starting
with 'vir' sets an errno instead of reporting an error the libvirt way.
Anyway, let's fix it, so the output changes from:

  $ virsh start arm
  error: Failed to start domain arm
  error: An error occurred, but the cause is unknown

to:

  $ virsh start arm
  error: Failed to start domain arm
  error: Cannot create directory '/var/lib/libvirt/qemu/domain-arm': Not
  a directory

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1146886Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

If the current live definition does not have memory hotplug enabled, but
the persistent one does libvirt would reject migration if the
destination does not support memory hotplug even if the user didn't want
to persist the VM at the destination and thus the XML containing the
memory hotplug definition would not be used. To fix this corner case the
code will check for memory hotplug in the newDef only if
VIR_MIGRATE_PERSIST_DEST was used.

Commit 35847860 Added the virFileUnlink function, but failed to add
a version for mingw build, causing the following error:

  Cannot export virFileUnlink: symbol not defined
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1260846

Introduced by 8fedbbdb, if we parse an unordered NUMA cell, will
get a segfault. This is because of a check for overlapping @cpus
sets we have there. However, since the array to hold guest NUMA
cells is allocated upfront and therefore it contains all zeros,
an out of order cell will break our assumption that cell IDs have
increasing character. At this point we try to access yet NULL
bitmap and therefore segfault.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>

Running valgrind on a very simplistic program consisting only of
opening and closing admin connection (virAdmConnect{Open,Close}) shows a
leak in remoteAdminPrivNew, because the last reference to privateData is
not decremented, thus the object won't be disposed. This patch unrefs
the privateData object once we closed the active connection to daemon,
making further use of this connection  useless.

==24577==    at 0x4A089C7: calloc (in /usr/lib64/valgrind/vgpreload_***linux.so)
==24577==    by 0x4E8835F: virAllocVar (viralloc.c:560)
==24577==    by 0x4EDFA5C: virObjectNew (virobject.c:193)
==24577==    by 0x4EDFBD4: virObjectLockableNew (virobject.c:219)
==24577==    by 0x4C14DAF: remoteAdminPrivNew (libvirt-admin.c:152)
==24577==    by 0x4C1537E: virAdmConnectOpen (libvirt-admin.c:308)
==24577==    by 0x400BAD: main (listservers.c:39)

==24577== LEAK SUMMARY:
==24577==    definitely lost: 80 bytes in 1 blocks
==24577==    indirectly lost: 840 bytes in 6 blocks
==24577==      possibly lost: 0 bytes in 0 blocks
==24577==    still reachable: 12,179 bytes in 199 blocks
==24577==         suppressed: 0 bytes in 0 blocks

https://bugzilla.redhat.com/show_bug.cgi?id=1172544

https://bugzilla.redhat.com/show_bug.cgi?id=1254420Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Remove the need for a couple of sa_asserts.

Coverity claims it could be possible to call virDBusTypeStackFree with
*stack == NULL and although the two API's that call it don't appear to
allow that - I suppose it's better to be safe than sorry

In virFileNBDDeviceFindUnused if virFileNBDDeviceIsBusy returns 0,
then both branches jumped to cleanup, so just use ignore_value
since the function returns NULL or some memory and the caller
handles the error.

Commit id '692e9fac' used virProcessSetNamespaces instead of inlining
the similar functionality; however, Coverity notes that the function
prototype expects a size_t value and not an enum and complains. So,
just typecast the enum as a size_t to avoid the noise.

Commit id '2e7cea24' added a check for an error from Finish instead
of 'unexpected error'; however, if for some reason there wasn't an
error, then virGetLastError could return NULL resulting in the
NULL pointer deref to err->domain.

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1258361

When attaching a disk, controller, or rng using an address type ccw
or s390, we need to ensure the support is provided by both the machine.os
and the emulator capabilities (corollary to unconditional setting when
address was not provided for the correct machine.os and emulator.

For an inactive guest, an addition followed by a start would cause the
startup to fail after qemu_command builds the command line and attempts
to start the guest. For an active guest, libvirtd would crash.

Rather than have different usages of STR function in order to determine
whether the domain is s390-ccw or s390-ccw-virtio, make a single API
which will check the machine.os prefix. Then use the function.

Remove redundant error reporting in libxlDomainMigrationPerform().
virNetSocketNewConnectTCP() is perfectly capable of reporting
sensible errors.

Commit d091518b tried to escape all strings in produced XML, but missed
this one.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Before libvirt sets the MAC address of the physdev (the physical
ethernet device) linked to a macvtap passthrough device, it always
saves the previous MAC address to restore when the guest is finished
(following a "leave nothing behind" policy). For a long time it
accomplished the save/restore with a combination of
ioctl(SIOCGIFHWADDR) and ioctl(SIOCSIFHWADDR), but in commit cbfe38c
(first in libvirt 1.2.15) this was changed to use netlink RTM_GETLINK
and RTM_SETLINK commands sent to the Physical Function (PF) of any
device that was detected to be a Virtual Function (VF).

We later found out that this caused problems with any devices using
the Cisco enic driver (e.g. vmfex cards) because the enic driver
hasn't implemented the function that is called to gather the
information in the IFLA_VFINFO_LIST attribute of RTM_GETLINK
(ndo_get_vf_config() for those keeping score), so we would never get
back a useful response.

In an ideal world, all drivers would implement all functions, but it
turns out that in this case we can work around this omission without
any bad side effects - since all macvtap passthrough <interface>
definitions pointing to a physdev that uses the enic driver *must*
have a <virtualport type='802.1Qbh'>, and since no other type of
ethernet devices use 802.1Qbh, libvirt can change its behavior in this
case to use the old-style.  ioctl(SIOC[GS]IFHWADDR).  That's what this
patch does.

Resolves:  https://bugzilla.redhat.com/show_bug.cgi?id=1257004

These functions were made static as a part of commit cbfe38c since
they were no longer called from outside virnetdev.c. We once again
need to call them from another file, so this patch makes them once
again public.

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: NMichal Privoznik <mprivozn@redhat.com>

Commit id '155ca616' added the 'refreshVol' API. In an NFS root-squash
environment it was possible that if the just created volume from XML wasn't
properly created with the right uid/gid and/or mode, then the followup
refreshVol will fail to open the volume in order to get the allocation/
capacity values. This would leave the volume still on the server and
cause a libvirtd crash because 'voldef' would be in the pool list, but
the cleanup code would free it.

Commit id '7c2d65dd' changed the default value of mode to be -1 if not
supplied in the XML, which should cause creation of the volume using the
default mode of VIR_STORAGE_DEFAULT_VOL_PERM_MODE; however, the check
made was whether mode was '0' or not to use default or provided value.

This patch fixes the issue to check if the 'mode' was provided in the XML
and use that value.

In an NFS root-squashed environment the 'vol-delete' command will fail to
'unlink' the target volume since it was created under a different uid:gid.

This code continues the concepts introduced in virFileOpenForked and
virDirCreate[NoFork] with respect to running the unlink command under
the uid/gid of the child. Unlike the other two, don't retry on EACCES
(that's why we're here doing this now).

This will only be seen when debugging, but in order to help determine
whether a virFileOpenForceOwnerMode failed during an NFS root-squash
volume/file creation, add an error message from the child.

Adds a new interface type using UDP sockets, this seems only applicable
to QEMU but have edited tree-wide to support the new interface type.

The interface type required the addition of a "localaddr" (local
address), this then maps into the following xml and qemu call.

<interface type='udp'>
  <mac address='52:54:00:5c:67:56'/>
  <source address='127.0.0.1' port='11112'>
    <local address='127.0.0.1' port='22222'/>
  </source>
  <model type='virtio'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</interface>

QEMU call:
	-net socket,udp=127.0.0.1:11112,localaddr=127.0.0.1:22222

Notice the xml "local" entry becomes the "localaddr" for the qemu call.

reference:
http://lists.gnu.org/archive/html/qemu-devel/2011-11/msg00629.htmlSigned-off-by: NJonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

Like we are checking for the correct order in SYM_FILES, we
should do the same for ADMIN_SYM_FILES.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

It's a generated file, so after 'distclean' it should be gone.
But it isn't yet.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

We have this check rule in src/Makefile: check-symfile that
should check if all symbols we wanted to export are exported.
Moreover, if we are not exporting something more. Do the same
with libvirt_admin.syms.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

f1f68ca3 moved the monitor socket to a per domain directory. Adjust the
path accordingly.

commit 09778e09 switched from using ioctl(SIOCBRDELBR) for bridge
device deletion to using a netlink RTM_DELLINK message, which is the
more modern way to delete a bridge (and also doesn't require the
bridge to be ~IFF_UP to succeed). However, although older kernels
(e.g. 2.6.32, in RHEL6/CentOS6) support deleting *some* link types
with RTM_NEWLINK, they don't support deleting bridges, and there is no
compile-time way to figure this out.

This patch moves the body of the SIOCBRDELBR version of
virNetDevBridgeDelete() into a static function, calls the new function
from the original, and also calls the new function from the
RTM_DELLINK version if the RTM_DELLINK message generates an EOPNOTSUPP
error. Since RTM_DELLINK is done from the subordinate function
virNetlinkDelLink, which is also called for other purposes (deleting a
macvtap interface), a function pointer called "fallback" has been
added to the arglist of virNetlinkDelLink() - if that arg != NULL, the
provided function will be called when (and only when) RTM_DELLINK
fails with EOPNOTSUPP.

Resolves:  https://bugzilla.redhat.com/show_bug.cgi?id=1252780 (part 2)

commit fc7b23db switched from using ioctl(SIOCBRADDBR) for bridge
creation to using a netlink RTM_NEWLINK message with IFLA_INFO_KIND =
"bridge", which is the more modern way to create a bridge. However,
although older kernels (e.g. 2.6.32, in RHEL6/CentOS6) support
creating *some* link types with RTM_NEWLINK, they don't support
creating bridges, and there is no compile-time way to figure this out
(since the "type" isn't an enum, but rather a character string).

This patch moves the body of the SIOCBRADDBR version of
virNetDevBridgeCreate() into a static function, calls the new function
from the original, and also calls the new function from the
RTM_NEWLINK version if the RTM_NEWLINK message generates an EOPNOTSUPP
error.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1252780