Packets sent by guests on virbrN, *or* by dnsmasq on the same, to
- 255.255.255.255/32 (netmask-independent local network broadcast
  address), or to
- 224.0.0.0/24 (local subnetwork multicast range)
are never forwarded, hence it is not necessary to masquerade them.

In fact we must not masquerade them: translating their source addresses or
source ports (where applicable) may confuse receivers on virbrN.

One example is the DHCP client in OVMF (= UEFI firmware for virtual
machines):

  http://thread.gmane.org/gmane.comp.bios.tianocore.devel/1506/focus=2640

It expects DHCP replies to arrive from remote source port 67. Even though
dnsmasq conforms to that, the destination address (255.255.255.255) and
the source address (eg. 192.168.122.1) in the reply allow the UDP
masquerading rule to match, which rewrites the source port to or above
1024. This prevents the DHCP client in OVMF from accepting the packet.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=709418Signed-off-by: NLaszlo Ersek <lersek@redhat.com>

The functions
- iptablesAddForwardDontMasquerade(),
- iptablesRemoveForwardDontMasquerade
handle exceptions in the masquerading implemented in the POSTROUTING chain
of the "nat" table. Such exceptions should be added as chronologically
latest, logically top-most rules.

The bridge driver will call these functions beginning with the next patch:
some special destination IP addresses always refer to the local
subnetwork, even though they don't match any practical subnetwork's
netmask. Packets from virbrN targeting such IP addresses are never routed
outwards, but the current rules treat them as non-virbrN-destined packets
and masquerade them. This causes problems for some receivers on virbrN.
Signed-off-by: NLaszlo Ersek <lersek@redhat.com>

The previous patches added infrastructure to report better errors from
monitor in some cases. This patch finalizes this "feature" by enabling
this enhanced error reporting on early phases of VM startup. In these
phases the possibility of qemu producing a useful error message is
really high compared to running it during the whole life cycle. After
the start up is complete, the feature is disabled to provide the usual
error messages so that users are not confused by possibly irrelevant
messages that may be in the domain log.

The original motivation to do this enhancement is to capture errors when
using VFIO device passthrough, where qemu reports errors after the
monitor is initialized and the existing error catching code couldn't
catch this producing a unhelpful message:

 # virsh start test
 error: Failed to start domain test
 error: Unable to read from monitor: Connection reset by peer

With this change, the message is changed to:

 # virsh start test
 error: Failed to start domain test
 error: internal error: early end of file from monitor: possible problem:
 qemu-system-x86_64: -device vfio-pci,host=00:1a.0,id=hostdev0,bus=pci.0,addr=0x5: vfio: error, group 8 is not viable, please ensure all devices within the iommu_group are bound to their vfio bus driver.
 qemu-system-x86_64: -device vfio-pci,host=00:1a.0,id=hostdev0,bus=pci.0,addr=0x5: vfio: failed to get group 8
 qemu-system-x86_64: -device vfio-pci,host=00:1a.0,id=hostdev0,bus=pci.0,addr=0x5: Device 'vfio-pci' could not be initialized

Change the monitor error code to add the ability to access the qemu log
file using a file descriptor so that we can dig in it for a more useful
error message. The error is now logged on monitor hangups and overwrites
a possible lesser error. A hangup on the monitor usualy means that qemu
has crashed and there's a significant chance it produced a useful error
message.

The functionality will be latent until the next patch.

Early VM startup errors usually produce a better error message in the
machine log file. Currently we were accessing it only when the process
exited during certain phases of startup. This will help adding a more
comprehensive error extraction for early qemu startup phases.

This patch adds infrastructure to keep a file descriptor for the machine
log file that will be used in case an error happens.

Teach the function to skip character device definitions printed by qemu
at startup in addition to libvirt log messages and make it usable from
outside of qemu_process.c. Also add documentation about the func.

The parsing of '-usb' did not check for failure of the
virDomainControllerInsert method. As a result on OOM, the
parser mistakenly attached USB disks to the IDE controller.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The code formatting NUMA args was ignoring the return value
of virBitmapFormat, so on OOM, it would silently drop the
NUMA cpumask arg.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When building boot menu args, if OOM occurred the CLI args
would end up containing  'order=(null)' due to a missing
call to 'virBufferError'.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The testutils.c file had some fprintfs which had not been
converted from %d to %zu, when 'testCounter' change to be
a size_t. This was a build breaker if --enable-test-oom
was enabled
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Since we're about to freeze, it's time to pick up the latest
upstream gnulib.  Among other changes, gnulib now guarantees the
use of some -f flags that we were previously manually adding.

* .gnulib: Update to latest, in part for warning improvements.
* m4/virt-compile-warnings.m4 (LIBVIRT_COMPILE_WARNINGS): Drop
flags that are now guaranteed by gnulib.
* bootstrap: Resync to gnulib.
Signed-off-by: NEric Blake <eblake@redhat.com>

On win32, using text mode for binary files might result in short
reads since ASCII character 0x1A is interpreted as EOF. Also, it
could lead to problems using the seek functions because of the \r
handling.
Signed-off-by: NClaudio Bley <cbley@av-test.de>

N.B.  This had no ill effects as long as O_RDONLY is defined to
      to be 0, such that the expression (O_RDONLY < 0) yielded 0
      again.
Signed-off-by: NClaudio Bley <cbley@av-test.de>

The virCommandAddEnvPassCommon method ignored the failure to
pre-allocate the env variable array with VIR_RESIZE_N. While
this is harmless, it confuses the test harness which is trying
to validate OOM handling of every individual allocation call.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When the various viralloc.c functions were changed to use the
normal error reporting code, the OOM injection code paths
were not updated to report errors.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The qemuParseCommandLine method did not check the return value of
virStringSplit to see if OOM had occurred. This lead to dereference
of a NULL pointer on OOM.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Most callers of qemuParseKeywords were assigning its return
value to a 'size_t' variable. Then then also checked '< 0'
for error condition, but this will never be true with the
unsigned size_t variable. Rather than using 'ssize_t', change
qemuParseKeywords so that the element count is returned via
an output parameter, leaving the return value solely as an
error indicator.

This avoids a crash accessing beyond the end of an error
upon OOM.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In

  commit 41b55056
  Author: Eric Blake <eblake@redhat.com>
  Date:   Wed Aug 28 15:01:23 2013 -0600

    qemu: simplify list cleanup

The qemuStringToArgvEnv method was changed to use virStringFreeList
to free the 'arglist' array. This method assumes the string list
array is NULL terminated, however, qemuStringToArgvEnv was not
ensuring this when populating 'arglist'. This caused an out of
bounds access by virStringFreeList when OOM occured in the initial
loop of qemuStringToArgvEnv
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When parsing the RBD hosts, it increments the 'nhosts' counter
before increasing the 'hosts' array allocation. If an OOM then
occurs when increasing the array allocation, the cleanup block
will attempt to access beyond the end of the array. Switch
to using VIR_EXPAND_N instead of VIR_REALLOC_N to protect against
this mistake
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If OOM occurs in qemuDomainCCWAddressSetCreate, it jumps to
a cleanup block and frees the partially initialized object.
It then mistakenly returns the address of the just free'd
pointer instead of NULL.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If a OOM error occurs in virGetConnect, this may cause the
virConnectDispose method to de-reference a NULL pointer,
since the close callback will not have been initialized.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virDomainDefParseXML method did not check the return value
of the virBitmapNew API call for NULL. This lead to a crash on
OOM
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If an OOM error occurs in virSecurityDeviceLabelDefParseXML the
cleanup code may free an uninitialized pointer, causing a crash
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Start a test case for the virNetServerClient object, which
initially checks the creation of a virIdentityPtr object.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

To allow creation of a virNetSocketPtr instance from a pre-opened
socketpair FD, add a virNetSocketNewConnectSockFD method.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

The new function virConnectGetCPUModelNames allows to retrieve the list
of CPU models known by the hypervisor for a specific architecture.
Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Nehal J. Wani reported on IRC a rather interesting build failure:

In file included from util/virnetdevbridge.c:53:0:
/usr/include/linux/in6.h:30:8: error: redefinition of 'struct in6_addr'
 struct in6_addr {
        ^

I traced it to the fact that he ran 'git pull; make check' across
commit e62e0094.  What happened is that the configure changes
result in a new variable that was set to be defined on his system,
but config.h was not regenerated to contain the value of that
variable.  Running 'make' instead of 'make check' cleaned up the
problem.  A bit more investigation, and I see that in Makefile.am,
automake sticks rules that rebuild config.h as part of 'make all',
and that we also had a dependency 'check-local: all'; BUT the
rule for check-local is run only at the point when the top-level
directory is visited.  Automake documents that SUBDIRS should
contain an explicit '.' at the point the top-level should be
visited (defaulting to last, if it doesn't appear).  Sure enough,
with this patch, 'make check' now does the top-level 'all' rules,
which regenerates 'config.h' BEFORE compiling any code that might
depend on changed content of that file.

* Makefile.am (SUBDIRS): Put '.' first, not last.
Signed-off-by: NEric Blake <eblake@redhat.com>

The fix for CVE-2013-4311 had a pre-requisite enhancement
to the identity code

  commit db7a5688
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Thu Aug 22 16:00:01 2013 +0100

    Also store user & group ID values in virIdentity

This had a typo which caused the group ID to overwrite the
user ID string. This meant any checks using this would have
the wrong ID value. This only affected the ACL code, not the
initial polkit auth. It also leaked memory.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The xml files are generated in build directory and thus docs/newapi.xsl
was not able to find them in a VPATH build.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

If a dir does not exist, raise an immediate error in logs
rather than letting virFileResolveAllLinks fail, since this
gives better error reporting to the user.
Signed-off-by: NChen Hanxiao <chenhanxiao@cn.fujitsu.com>

When FUSE is enabled, the LXC container is setup with
a custom /proc/meminfo file. This file uses "KB" as a
suffix, rather than "kB" which is the kernel's style.
Fix this inconsistency to avoid confusing apps.
Signed-off-by: NChen Hanxiao <chenhanxiao@cn.fujitsu.com>

The ABI compatibility check for domain features didn't check the
expanded HyperV and APIC EOI values, thus possibly allowing change in
guest ABI.

Add the check and use typecasted switch statement to warn developers
when adding a new HyperV feature.

The virDomainGetVcpuPinInfo python wrapper had a potential use of
uninitialized values
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>