Commit Graph

414 Commits

Author SHA1 Message Date
Laine Stump
9065cfaa88 network: allow disabling dnsmasq's DNS server
If you define a libvirt virtual network with one or more IP addresses,
it starts up an instance of dnsmasq. It's always been possible to
avoid dnsmasq's dhcp server (simply don't include a <dhcp> element),
but until now it wasn't possible to avoid having the DNS server
listening; even if the network has no <dns> element, it is started
using default settings.

This patch adds a new attribute to <dns>: enable='yes|no'. For
backward compatibility, it defaults to 'yes', but if you don't want a
DNS server created for the network, you can simply add:

   <dns enable='no'/>

to the network configuration, and next time the network is started
there will be no dns server created (if there is dhcp configuration,
dnsmasq will be started with "port=0" which disables the DNS server;
if there is no dhcp configuration, dnsmasq won't be started at all).
2016-08-19 21:10:34 -04:00
Laine Stump
25e8112d7c network: new network forward mode 'open'
The new forward mode 'open' is just like mode='route', except that no
firewall rules are added to assure that any traffic does or doesn't
pass. It is assumed that either they aren't necessary, or they will be
setup outside the scope of libvirt.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=846810
2016-08-19 21:05:15 -04:00
Anton Khramov
128a8b2c9f network: Added hook for network modification event
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1181539
2016-07-26 12:40:14 -04:00
Maxim Perevedentsev
527968d433 dnsmasq: disable IPv6 default gateway in RA for isolated networks
IPv6 RA always contains an implicit default route via
the link-local address of the source of RA. This forces
the guest to install a route via isolated network, which
may disturb the guest's networking in case of multiple interfaces.
More info in 013427e6e7.

The validity of this route is controlled by "default [route] lifetime"
field of RA. If the lifetime is set to 0 seconds, then no route
is installed by receiver.

dnsmasq 2.67+ supports "ra-param=<interface>,<RA interval>,<default
lifetime>" option. We pass "ra-param=*,0,0"
(here, RA_interval=0 means default) to disable default gateway in RA
for isolated networks.
2016-07-13 13:49:03 +03:00
Laine Stump
fa18e814ba util: move IP route & address object-related functions to virnetdevip.c
These functions all need to be called from a utility function that
must be located in the util directory, so we move them all into
util/virnetdevip.[ch] now that it exists.

Function and struct names were appropriately changed for the new
location, but all code is unchanged aside from motion and renaming.
2016-06-26 19:33:09 -04:00
Laine Stump
cf0568b0af util: new files virnetdevip.[ch] for IP-related netdev functions
This patch splits virnetdev.[ch] into multiple files, with the new
virnetdevip.[ch] containing all the functions related to setting and
retrieving IP-related info for a device (both addresses and routes).
2016-06-26 19:33:09 -04:00
Laine Stump
22a6873a98 global: consistently use IP rather than Ip in identifiers
I'm tired of mistyping this all the time, so let's do it the same all
the time (similar to how we changed all "Pci" to "PCI" awhile back).

(NB: I've left alone some things in the esx and vbox drivers because
I'm unable to compile them and they weren't obviously *not* a part of
some API. I also didn't change a couple of variables named,
e.g. "somethingIptables", because they were derived from the name of
the "iptables" command)
2016-06-26 19:33:07 -04:00
Ján Tomko
42b4a37d68 Use virDirOpenIfExists
Use it instead of opendir everywhere we need to check for ENOENT.
2016-06-24 14:20:57 +02:00
Ján Tomko
fe79c3f2c1 Do not check for '.' and '..' after virDirRead
It skips those directory entries.
2016-06-23 21:58:38 +02:00
Ján Tomko
a4e6f1eb9c Introduce VIR_DIR_CLOSE
Introduce a helper that only calls closedir if DIR* is non-NULL
and sets it to NULL afterwards.
2016-06-23 21:58:33 +02:00
Laine Stump
93b59fcff6 network: restart dnsmasq after adding/removing txt and srv records
Although dns host records are stored in a separate configuration file
that is reread by dnsmasq when it receives a SIGHUP, the txt and srv
records are directly in the dnsmasq .conf file which can't be reread
after initial dnsmasq startup. This means that if an srv or txt record
is modified in a network config, libvirt needs to restart the dnsmasq
process rather than just sending a SIGHUP.

This was pointed out in a question in
https://bugzilla.redhat.com/show_bug.cgi?id=988718 , but no separate
BZ was filed.
2016-06-01 11:45:25 -04:00
Laine Stump
9575cb8554 network: log error when <bandwidth> is requested for hostdev interfaces
This would previously be silently ignored.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1319044
2016-05-13 10:02:20 -04:00
Laine Stump
75db9997a0 util: set vlan tag for macvtap passthrough mode on SRIOV VFs
SRIOV VFs used in macvtap passthrough mode can take advantage of the
SRIOV card's transparent vlan tagging. All the code was there to set
the vlan tag, and it has been used for SRIOV VFs used for hostdev
interfaces for several years, but for some reason, the vlan tag for
macvtap passthrough devices was stubbed out with a -1.

This patch moves a bit of common validation down to a lower level
(virNetDevReplaceNetConfig()) so it is shared by hostdev and macvtap
modes, and updates the macvtap caller to actually send the vlan config
instead of -1.
2016-05-10 14:04:19 -04:00
John Ferlan
4fac5a9fd3 Use virGetLastErrorMessage to avoid Coverity message
Both instances use VIR_WARN() to print the error from a failed
virDBusGetSystemBus() call.  Rather than use the virGetLastError
and need to check for valid return err pointer, just use the
virGetLastErrorMessage.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2016-05-09 19:33:56 -04:00
Cole Robinson
26af7e4e93 network: Fix segfault on daemon reload
We will segfault of a daemon reload picks up a new network config
that needs to be autostarted. We shouldn't be passing NULL for
network_driver here. This seems like it was missed in the larger
rework in commit 1009a61e
2016-05-02 10:06:04 -04:00
Martin Kletzander
c36b1f7b6a Change virDevicePCIAddress to virPCIDeviceAddress
We had both and the only difference was that the latter also included
information about multifunction setting.  The problem with that was that
we couldn't use functions made for only one of the structs (e.g.
parsing).  To consolidate those two structs, use the one in virpci.h,
include that in domain_conf.h and add the multifunction member in it.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2016-05-02 15:46:23 +02:00
Laine Stump
bf3d9f305e network: fix DHCPv6 on networks with prefix != 64
According to the dnsmasq manpage, the netmask for IPv4 address ranges
will be auto-deteremined from the interface dnsmasq is listening on,
but it can't do this for IPv6 for some reason - it instead assumes a
network prefix of 64 for all IPv6 address ranges. If this is
incorrect, dnsmasq will refuse to give out an address to clients,
instead logging this message:

 dnsmasq-dhcp[2380]: no address range available for DHCPv6 request via virbr0

The solution is for libvirt to add ",$prefix" to all IPv6 dhcp-range
arguments when building the dnsmasq.conf file.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1033739
2016-04-21 15:06:25 -04:00
Vasiliy Tolstov
b3d069872c virnetdev allow to set peer address
Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>
2016-04-07 18:22:58 +01:00
Laine Stump
3992ff14e5 network: new function networkGetActualType
There are times when it's necessary to learn the actual type of a
network connection before any resources have been allocated
(e.g. during qemuProcessPrepareDomain()), but in the past it was
necessary to call networkAllocateActualDevice() in order to have the
actual type filled in.

This new function returns the type of network that *will be* setup
once it actually happens, but without making any changes on the host.
2016-04-04 07:03:12 -04:00
Laine Stump
b41261f010 network: call proper start/stop functions for macvtap bridge-mode networks
networkStartNetwork() and networkShutdownNetwork() were calling the
wrong type-specific function in the case of networks that were
configured for macvtap ("direct") bridge mode - they were instead
calling the functions for a tap+bridge network. Currently none of
these functions does anything (they just return 0) so it hasn't
created any problems, but that could change in the future.
2016-03-25 13:28:34 -04:00
Laine Stump
2a537fe187 network: differentiate macvtap/bridge from host-bridge based networks
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1316465

An attempt to simplify the code for the VIR_NETWORK_FORWARD_BRIDGE
case of networkUpdateState in commit b61db335 (first in release
1.2.14) resulted in networks based on macvtap bridge mode being
erroneously marked as inactive any time libvirtd was restarted.

The problem is that the original code had differentiated between a
network using tap devices to connect to an existing host-bridge device
(forward mode of VIR_NETWORK_FORWARD_BRIDGE and a non-NULL
def->bridge), and one using macvtap bridge mode to connect to any
ethernet device (still forward mode VIR_NETWORK_FORWARD_BRIDGE, but
null def->bridge), but the changed code assumed that all networks with
VIR_NETWORK_FORWARD_BRIDGE were tap + host-bridge networks, so a null
def->bridge was interpreted as "inactive".

This patch restores the original code in networkUpdateState
2016-03-25 13:21:29 -04:00
Michal Privoznik
865764de06 Drop paths.h include
We include the file in plenty of places. This is mostly due to
historical reasons. The only place that needs something from the
header file is storage_backend_fs which opens _PATH_MOUNTED. But
it gets the file included indirectly via mntent.h. At no other
place in our code we need _PATH_.*. Drop the include and
configure check then.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-03-18 09:43:45 +01:00
Shanzhi Yu
347035f959 qemu: improve the error when try to undefine transient network
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1315059

Signed-off-by: Shanzhi Yu <shyu@redhat.com>
2016-03-07 10:15:53 +01:00
Laine Stump
eb72bd63c1 network: consolidated info log for all network allocate/free operations
There are three functions that deal with allocating and freeing
devices from a networks netdev/pci device pool:
network(Allocate|Notify|Release)ActualDevice(). These functions also
maintain a counter of the number of domains currently using a network
(regardless of whether or not that network uses a device pool). Each
of these functions had multiple log messages (output using VIR_DEBUG)
that were in slightly different formats and gave varying amounts of
information.

This patch creates a single function to log the pertinent information
in a consistent manner for all three of these functions. Along with
assuring that all the functions produce a consistent form of output
(and making it simpler to change), it adds the MAC address of the
domain interface involved in the operation, making it possible to
verify which interface of which domain the operation is being done for
(assuming that all MAC addresses are unique, of course).

All of these messages are raised from DEBUG to INFO, since they don't
happen that often (once per interface per domain/libvirtd start or
domain stop), and can be very informative and helpful - eliminating
the need to log debug level messages makes it much easier to sort
these out.
2016-02-14 11:28:45 -05:00
Laine Stump
3ea8b8b87f network: consolidate connection count updates for device pool
networkReleaseActualDevice() and networkNotifyActualDevice() both were
updating the individual devices' connections count in two separate
places (unlike networkAllocateActualDevice() which does it in a single
unified place after success:). The code is correct, but prone to
confusion / later breakage. All of these updates are anyway located at
the end of if/else clauses that are (with the exception of a single
VIR_DEBUG() in each case) immediately followed by the success: label
anyway, so this patch replaces the duplicated ++/-- instructions with
a single ++/-- inside a qualifying "if (dev)" down below success:.
(NB: if dev != NULL, by definition we are using a device (either pci
or netdev, doesn't matter for these purposes) from the network's pool)

The VIR_DEBUG args (which will be replaced in a followup patch anyway)
were all adjusted to account for the connection count being out of
date at the time.
2016-02-14 11:27:27 -05:00
Joao Martins
d239a5427f conf: add caps to virDomainDefFormat*
And use the newly added caps->host.netprefix (if it exists) for
interface names that match the autogenerated target names.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
2016-02-04 12:38:26 +00:00
Ján Tomko
1e6d87bdfc bridge: check for invalid MAC in networkGetDHCPLeases
Instead of comparing garbage strings against real MAC addresses,
introduce an error mesage for unparsable ones:

$ virsh net-dhcp-leases default  --mac t12
error: Failed to get leases info for default
error: invalid MAC address: t12

https://bugzilla.redhat.com/show_bug.cgi?id=1261432
2015-12-03 10:15:22 +01:00
Laine Stump
f391889f4e nodedev: report maxCount for virtual_functions capability
A PCI device may have the capability to setup virtual functions (VFs)
but have them currently all disabled. Prior to this patch, if that was
the case the the node device XML for the device wouldn't report any
virtual_functions capability.

With this patch, if a file called "sriov_totalvfs" is found in the
device's sysfs directory, its contents will be interpreted as a
decimal number, and that value will be reported as "maxCount" in a
capability element of the device's XML, e.g.:

   <capability type='virtual_functions' maxCount='7'/>

This will be reported regardless of whether or not any VFs are
currently enabled for the device.

NB: sriov_numvfs (the number of VFs currently active) is also
available in sysfs, but that value is implied by the number of items
in the list that is inside the capability element, so there is no
reason to explicitly provide it as an attribute.

sriov_totalvfs and sriov_numvfs are available in kernels at least as far
back as the 2.6.32 that is in RHEL6.7, but in the case that they
simply aren't there, libvirt will behave as it did prior to this patch
- no maxCount will be displayed, and the virtual_functions capability
will be absent from the device's XML when 0 VFs are enabled.
2015-11-24 12:31:04 -05:00
Maxim Perevedentsev
0f7436ca54 network: wait for DAD to finish for bridge IPv6 addresses
commit db488c79 assumed that dnsmasq would complete IPv6 DAD before
daemonizing, but in reality it doesn't wait, which creates problems
when libvirt's bridge driver sets the matching "dummy tap device" to
IFF_DOWN prior to DAD completing.

This patch waits for DAD completion by periodically polling the kernel
using netlink to check whether there are any IPv6 addresses assigned
to bridge which have a 'tentative' state (if there are any in this
state, then DAD hasn't yet finished). After DAD is finished, execution
continues. To avoid an endless hang in case something was wrong with
the kernel's DAD, we wait a maximum of 5 seconds.
2015-10-28 21:48:04 -04:00
Michal Privoznik
4f77c48cba virJSONValueArraySize: return ssize_t
The internal representation of a JSON array counts the items in
size_t. However, for some reason, when asking for the count it's
reported as int. Firstly, we need the function to return a signed
type as it's returning -1 on an error. But, not every system has
integer the same size as size_t. Therefore, lets return ssize_t.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-10-09 15:25:08 +02:00
Michal Privoznik
f7fba69bd7 networkBandwidthGenericChecks: Drop useless check
There's a check right at the beginning of the function that
shortcuts if the function was called over all NULL arguments.
However, this was meant just as a fool-proof check so that we
don't crash if function is used in a bad manner. Anyway, it makes
Coverity unhappy as it then thinks any of the arguments could be
NULL. Well, with the current state of the code it can't.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-08-12 10:57:36 +02:00
Michal Privoznik
ef6b3b625d networkBandwidthUpdate: Don't blindly dereference pointers
It may happen that an interface don't have any bandwidth set and
a new one is to be set. In that case, @ifaceBand will be NULL.
This will cause troubles later in the code when deciding what to
do.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-08-12 10:57:36 +02:00
Michal Privoznik
812932bea2 bridge_driver: Introduce networkBandwidthUpdate
So, if a domain vNIC's bandwidth has been successfully set, it's
possible that because @floor is set on network's bridge, this
part may need updating too. And that's exactly what this function
does. While the previous commit introduced a function to check if
@floor can be satisfied, this does all the hard work. In general,
there may be three, well four possibilities:

  1) No change in @floor value (either it remain unset, or its
  value hasn't changed)

  2) The @floor value has changed from a non-zero to a non-zero
  value

  3) New @floor is to be set

  4) Old @floor must be cleared out

The difference between 2), 3) and 4) is, that while in 2) the QoS
tree on the network's bridge already has a special class for the
vNIC, in 3) the class must be created from scratch. In 4) it must
be removed. Fortunately, we have helpers for all three
interesting cases.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-08-11 16:10:32 +02:00
Michal Privoznik
41a1531de5 bridge_driver: Introduce networkBandwidthChangeAllowed
When a domain vNIC's bandwidth is to be changed (at runtime) it is
possible that guaranteed minimal bandwidth (@floor) will change too.
Well, so far it is, because we still don't have an implementation that
allows setting it dynamically, so it's effectively erased on:

    #virsh domiftune $dom vnet0 --inbound 0

However, that's slightly unfortunate. We do some checks on domain
startup to see if @floor can be guaranteed. We ought do the same if
QoS is changed at runtime.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-08-11 16:10:32 +02:00
Michal Privoznik
45090449c4 virNetDevBandwidthUpdateRate: turn class_id into integer
This is no functional change. It's just that later in the series we
will need to pass class_id as an integer.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-08-11 16:10:32 +02:00
Ján Tomko
12b949dfb2 maint: remove incorrect apostrophes from 'its' 2015-06-04 10:01:42 +02:00
Laine Stump
55ace7c478 util: report all address range errors in virSocketAddrGetRange()
There are now many more reasons that virSocketAddrGetRange() could
fail, so it is much more informative to report the error there instead
of in the caller. (one of the two callers was previously assuming
success, which is almost surely safe based on the parsing that has
already happened to the config by that time, but it still is nicer to
account for an error "just in case")

Part of fix for: https://bugzilla.redhat.com/show_bug.cgi?id=985653
2015-06-02 12:40:07 -04:00
Laine Stump
198d503c64 network: cleanup range loop in networkDnsmasqConfContents
This loop had automatic variable definitions mixed with code. This
patch moves the definitions to the top of the function and puts
cleanup for them at the bottom. No functional change.

Part of fix for: https://bugzilla.redhat.com/show_bug.cgi?id=985653
2015-06-02 12:40:07 -04:00
Laine Stump
1e334a0a00 network: validate DHCP ranges are completely within defined network
virSocketAddrGetRange() has been updated to take the network address
and prefix, and now checks that both the start and end of the range
are within that network, thus validating that the entire range of
addresses is in the network. For IPv4, it also checks that ranges to
not start with the "network address" of the subnet, nor end with the
broadcast address of the subnet (this check doesn't apply to IPv6,
since IPv6 doesn't have a broadcast or network address)

Negative tests have been added to the network update and socket tests
to verify that bad ranges properly generate an error.

This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=985653
2015-06-02 12:40:07 -04:00
John Ferlan
38f0fc19af network: Resolve Coverity FORWARD_NULL
To silence Coverity just add a 'p &&' in front of the check in
networkFindUnusedBridgeName after the strchr() call.  Even though
we know it's not possible to have strchr return NULL since the only
way into the function is if there is a '%' in def->bridge or it's NULL.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2015-05-24 07:01:48 -04:00
Ján Tomko
076dd37995 Ignore bridge template names with multiple printf conversions
For some reason, we allow a bridge name with %d in it, which we replace
with an unsigned integer to form a bridge name that does not yet exist
on the host.

Do not blindly pass it to virAsprintf if it's not the only conversion,
to prevent crashing on input like:

<network>
  <name>test</name>
  <forward mode='none'/>
  <bridge name='virbr%d%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s'/>
</network>

Ignore any template strings that do not have exactly one %d conversion,
like we do in various drivers before calling virNetDevTapCreateInBridgePort.
2015-05-11 14:14:33 +02:00
Laine Stump
37b8bc6f12 network: check for bridge name conflict with existing devices
Since some people use the same naming convention as libvirt for bridge
devices they create outside the context of libvirt, it is much nicer
if we check for those devices when looking for a bridge device name to
auto-assign to a new network.
2015-04-28 01:21:41 -04:00
Laine Stump
a28d3e485f network: move auto-assign of bridge name from XML parser to net driver
We already check that any auto-assigned bridge device name for a
virtual network (e.g. "virbr1") doesn't conflict with the bridge name
for any existing libvirt network (via virNetworkSetBridgeName() in
conf/network_conf.c).

We also want to check that the name doesn't conflict with any bridge
device created on the host system outside the control of libvirt
(history: possibly due to the ploriferation of references to libvirt's
bridge devices in HOWTO documents all around the web, it is not
uncommon for an admin to manually create a bridge in their host's
system network config and name it "virbrX"). To add such a check to
virNetworkBridgeInUse() (which is called by virNetworkSetBridgeName())
we would have to call virNetDevExists() (from util/virnetdev.c); this
function calls ioctl(SIOCGIFFLAGS), which everyone on the mailing list
agreed should not be done from an XML parsing function in the conf
directory.

To remedy that problem, this patch removes virNetworkSetBridgeName()
from conf/network_conf.c and puts an identically functioning
networkBridgeNameValidate() in network/bridge_driver.c (because it's
reasonable for the bridge driver to call virNetDevExists(), although
we don't do that yet because I wanted this patch to have as close to 0
effect on function as possible).

There are a couple of inevitable changes though:

1) We no longer check the bridge name during
   virNetworkLoadConfig(). Close examination of the code shows that
   this wasn't necessary anyway - the only *correct* way to get XML
   into the config files is via networkDefine(), and networkDefine()
   will always call networkValidate(), which previously called
   virNetworkSetBridgeName() (and now calls
   networkBridgeNameValidate()). This means that the only way the
   bridge name can be unset during virNetworkLoadConfig() is if
   someone edited the config file on disk by hand (which we explicitly
   prohibit).

2) Just on the off chance that somebody *has* edited the file by hand,
   rather than crashing when they try to start their malformed
   network, a check for non-NULL bridge name has been added to
   networkStartNetworkVirtual().

   (For those wondering why I don't instead call
   networkValidateBridgeName() there to set a bridge name if one
   wasn't present - the problem is that during
   networkStartNetworkVirtual(), the lock for the network being
   started has already been acquired, but the lock for the network
   list itself *has not* (because we aren't adding/removing a
   network). But virNetworkBridgeInuse() iterates through *all*
   networks (including this one) and locks each network as it is
   checked for a duplicate entry; it is necessary to lock each network
   even before checking if it is the designated "skip" network because
   otherwise some other thread might acquire the list lock and delete
   the very entry we're examining. In the end, permitting a setting of
   the bridge name during network start would require that we lock the
   entire network list during any networkStartNetwork(), which
   eliminates a *lot* of parallelism that we've worked so hard to
   achieve (it can make a huge difference during libvirtd startup). So
   rather than try to adjust for someone playing against the rules, I
   choose to instead give them the error they deserve.)

3) virNetworkAllocateBridge() (now removed) would leak any "template"
   string set as the bridge name. Its replacement
   networkFindUnusedBridgeName() doesn't leak the template string - it
   is properly freed.
2015-04-28 01:20:11 -04:00
Ján Tomko
031323830d Support IPv6 in networkGetNetworkAddress
We've been explicitly requesting IPv4 for some reason,
even if there were only IPv6 addresses in the network
definition.

https://bugzilla.redhat.com/show_bug.cgi?id=1192318
2015-04-10 15:01:17 +02:00
John Ferlan
61fee39967 util: Replace virNetDevGetIPv4Address with virNetDevGetIPAddress
Rename it to virNetDevGetIPv4AddressIoctl and make
virNetDevGetIPAddress a wrapper around it, allowing
other ways of getting the address to be implemented,
and still falling back to the old method.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2015-04-10 15:01:17 +02:00
Michal Privoznik
d9706aea18 network_conf: Drop virNetworkObjIsDuplicate
This function does not make any sense now, that network driver is
(almost) dropped. I mean, previously, when threads were
serialized, this function was there to check, if no other network
with the same name or UUID exists. However, nowadays that threads
can run more in parallel, this function is useless, in fact it
gives misleading return values. Consider the following scenario.
Two threads, both trying to define networks with same name but
different UUID (e.g. because it was generated during XML parsing
phase, whatever). Lets assume that both threads are about to call
networkValidate() which immediately calls
virNetworkObjIsDuplicate().

T1: calls virNetworkObjIsDuplicate() and since no network with
given name or UUID exist, success is returned.
T2: calls virNetworkObjIsDuplicate() and since no network with
given name or UUID exist, success is returned.

T1: calls virNetworkAssignDef() and successfully places its
network into the virNetworkObjList.
T2: calls virNetworkAssignDef() and since network with the same
name exists, the network definition is replaced.

Okay, this is mainly because virNetworkAssignDef() does not check
whether name and UUID matches. Well, lets make it so! And drop
useless function too.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-03-23 09:56:15 +01:00
Michal Privoznik
dd7bfb2cdc networkStateInitialize: Don't lock network driver
There's no need to lock the network driver, as network driver
initialization is done prior accepting any client. There's nobody
to hop in and do something over partially initialized driver. Nor
qemu driver is doing that.

==30532== Observed (incorrect) order is: acquisition of lock at 0x1439EF50
==30532==    at 0x4C31A26: pthread_mutex_lock (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0x5324895: virMutexLock (virthread.c:88)
==30532==    by 0x5307E86: virObjectLock (virobject.c:323)
==30532==    by 0x5396440: virNetworkObjListForEach (network_conf.c:4511)
==30532==    by 0x19B29308: networkStateInitialize (bridge_driver.c:686)
==30532==    by 0x53E1CCC: virStateInitialize (libvirt.c:777)
==30532==    by 0x11DEB7: daemonRunStateInit (libvirtd.c:906)
==30532==    by 0x5324B6A: virThreadHelper (virthread.c:197)
==30532==    by 0x4C30456: ??? (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0xA1EC1F2: start_thread (in /lib64/libpthread-2.19.so)
==30532==    by 0xA4EDC8C: clone (in /lib64/libc-2.19.so)
==30532==
==30532==  followed by a later acquisition of lock at 0x1439CD60
==30532==    at 0x4C31A26: pthread_mutex_lock (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0x5324895: virMutexLock (virthread.c:88)
==30532==    by 0x19B27B2C: networkDriverLock (bridge_driver.c:102)
==30532==    by 0x19B27B60: networkGetDnsmasqCaps (bridge_driver.c:113)
==30532==    by 0x19B2856A: networkUpdateState (bridge_driver.c:389)
==30532==    by 0x53963E9: virNetworkObjListForEachHelper (network_conf.c:4488)
==30532==    by 0x52E2224: virHashForEach (virhash.c:521)
==30532==    by 0x539645B: virNetworkObjListForEach (network_conf.c:4512)
==30532==    by 0x19B29308: networkStateInitialize (bridge_driver.c:686)
==30532==    by 0x53E1CCC: virStateInitialize (libvirt.c:777)
==30532==    by 0x11DEB7: daemonRunStateInit (libvirtd.c:906)
==30532==    by 0x5324B6A: virThreadHelper (virthread.c:197)
==30532==
==30532== Required order was established by acquisition of lock at 0x1439CD60
==30532==    at 0x4C31A26: pthread_mutex_lock (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0x5324895: virMutexLock (virthread.c:88)
==30532==    by 0x19B27B2C: networkDriverLock (bridge_driver.c:102)
==30532==    by 0x19B28DF9: networkStateInitialize (bridge_driver.c:609)
==30532==    by 0x53E1CCC: virStateInitialize (libvirt.c:777)
==30532==    by 0x11DEB7: daemonRunStateInit (libvirtd.c:906)
==30532==    by 0x5324B6A: virThreadHelper (virthread.c:197)
==30532==    by 0x4C30456: ??? (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0xA1EC1F2: start_thread (in /lib64/libpthread-2.19.so)
==30532==    by 0xA4EDC8C: clone (in /lib64/libc-2.19.so)
==30532==
==30532==  followed by a later acquisition of lock at 0x1439EF50
==30532==    at 0x4C31A26: pthread_mutex_lock (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0x5324895: virMutexLock (virthread.c:88)
==30532==    by 0x5307E86: virObjectLock (virobject.c:323)
==30532==    by 0x538A09C: virNetworkAssignDef (network_conf.c:527)
==30532==    by 0x5391EB2: virNetworkLoadState (network_conf.c:3008)
==30532==    by 0x53922D4: virNetworkLoadAllState (network_conf.c:3128)
==30532==    by 0x19B2929A: networkStateInitialize (bridge_driver.c:671)
==30532==    by 0x53E1CCC: virStateInitialize (libvirt.c:777)
==30532==    by 0x11DEB7: daemonRunStateInit (libvirtd.c:906)
==30532==    by 0x5324B6A: virThreadHelper (virthread.c:197)
==30532==    by 0x4C30456: ??? (in /usr/lib64/valgrind/vgpreload_helgrind-amd64-linux.so)
==30532==    by 0xA1EC1F2: start_thread (in /lib64/libpthread-2.19.so)

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-03-23 09:56:15 +01:00
John Ferlan
0e3c68acd8 network: Resolve Coverity FORWARD_NULL
The following is a long winded way to say this patch is avoiding a
false positive.

Coverity complains that calling networkPlugBandwidth() could eventually
end up with a NULL dereference on iface->bandwidth because in the
networkAllocateActualDevice there's a check of 'iface->bandwidth'
before deciding to try to use the 'portgroup' if it exists or to not
perferm the virNetDevBandwidthCopy if 'bandwidth' is not NULL.

Later in networkPlugBandwidth the 'iface->bandwidth' is sourced from
virDomainNetGetActualBandwidth - which would be either iface->bandwidth
or (preferably) iface->data.network.actual->bandwidth which would have
been filled in from either 'iface->bandwidth' or 'portgroup->bandwidth'
back in networkAllocateActualDevice

There *is* a check in networkCheckBandwidth for the result of the
virDomainNetGetActualBandwidth being NULL and a return 1 based on
that which would cause networkPlugBandwidth to exit properly and thus
never hit the condition that Coverity complains about.

However, since Coverity checks all paths - it somehow believes that
a return of 0 by networkCheckBandwidth in this condition would end
up causing the possible NULL dereference. The "fix" to silence Coverity
is to not have networkCheckBandwidth also call virDomainNetGetActualBandwidth
in order to get the ifaceBand, but rather have it accept it as an argument
which causes Coverity to "see" that it's the exit condition of 1 that won't
have the possible NULL dereference.  Since we're passing that, I added the
passing of iface->mac rather than passing iface as well. This just hopefully
makes sure someone doesn't undo this in the future...
2015-03-18 06:56:24 -04:00
Eric Blake
eea08abec5 network: avoid memory leak of dnsmasq capabilities
Valgrind detected a leak:

==17820== 102 (56 direct, 46 indirect) bytes in 1 blocks are definitely lost in loss record 479 of 646
==17820==    at 0x4A08946: calloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==17820==    by 0x508521A: virAllocVar (viralloc.c:560)
==17820==    by 0x50D9FCA: virObjectNew (virobject.c:193)
==17820==    by 0x50A4FD9: dnsmasqCapsNewEmpty (virdnsmasq.c:784)
==17820==    by 0x50A514E: dnsmasqCapsNewFromBinary (virdnsmasq.c:830)
==17820==    by 0x1B508287: networkStateInitialize (bridge_driver.c:666)

It looks like commit 172acef introduced the problem, because
networkGetDnsmasqCaps() increments the reference count but an
early exit never does a matching decrement.

* src/network/bridge_driver.c (networkStateCleanup): Plug leak.

Signed-off-by: Eric Blake <eblake@redhat.com>
2015-03-14 21:01:26 -06:00
Michal Privoznik
eb7b635582 bridge_driver: Use more of networkObjFromNetwork
Now that the network driver lock is ash heap of history,
we can use more of networkObjFromNetwork().

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-03-13 15:55:56 +01:00