Pre-Glib era which used malloc allowed the size of the client-side
buffers to be declared as 0, because malloc documents that it can either
return 0 or a unique pointer on 0 size allocations.
With glib this doesn't work anymore, because glib documents that for
such allocation requests NULL is always returned which results in an
error in our public API checks server-side.
This patch complements the fix in the RPC layer by explicitly erroring
out on the following combination of args used by our legacy APIs (their
moder equivalents don't suffer from this):

function(caller-allocated-array, size, ...) {
    if (!caller-allocated-array && size > 0)
        return error;
}

treating everything else as a valid input and potentially let that fail
on the server-side rather than client-side.

https://bugzilla.redhat.com/show_bug.cgi?id=1772842Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

The qemu_domain_monitor_event_msg struct in qemu_protocol.x
defines event as a nonnull_string and qemuMonitorJSONIOProcessEvent
also errors out on a non-NULL event.

Drop the check to fix the build with static analysis.

This essentially reverts commit d343e820Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Adding build time self tests for basic (deprecated), doorbell and plain mode.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Shared memory devices need qemu to be able to access certain paths
either for the shared memory directly (mostly ivshmem-plain) or for a
socket (mostly ivshmem-doorbell).

Add logic to virt-aa-helper to render those apparmor rules based
on the domain configuration.

https://bugzilla.redhat.com/show_bug.cgi?id=1761645Reviewed-by: NCole Robinson <crobinso@redhat.com>
Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

There are currently broken use cases, e.g. snapshotting more than one disk at
once like:
 $ virsh snapshot-create-as --domain eoan --disk-only --atomic
   --diskspec vda,snapshot=no  --diskspec vdb,snapshot=no
   --diskspec vdc,file=/test/disk1.snapshot1.qcow,snapshot=external
   --diskspec vdd,file=/test/disk2.snapshot1.qcow,snapshot=external
The command above will iterate from qemuDomainSnapshotCreateDiskActive and
eventually add /test/disk1.snapshot1.qcow first (appears in the rules)
to then later add /test/disk2.snapshot1.qcow and while doing so throwing
away the former rule causing it to fail.

All other calls to (re)load_profile already use append=true when adding
rules append=false is only used when restoring rules [1].

Fix this by letting AppArmorSetSecurityImageLabel use append=true as well.

Since this is removing a (unintentional) trigger to revoke all rules
appended so far we agreed on review to do some tests, but in the tests
no rules came back on:
- hot-plug
- hot-unplug
- snapshotting

Bugs:
https://bugs.launchpad.net/libvirt/+bug/1845506
https://bugzilla.redhat.com/show_bug.cgi?id=1746684

[1]: https://bugs.launchpad.net/libvirt/+bug/1845506/comments/13Reviewed-by: NCole Robinson <crobinso@redhat.com>
Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

A lot of the code in AppArmorSetSecurityImageLabel is a duplicate of
what is in reload_profile, this refactors AppArmorSetSecurityImageLabel
to use reload_profile instead.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

reload_profile calls get_profile_name for no particular gain, lets
remove that call. The string isn't used in that function later on
and not registered/passed anywhere.

It can only fail if it either can't allocate or if the
virDomainDefPtr would have no uuid set (which isn't allowed).

Thereby the only "check" it really provides is if it can allocate the
string to then free it again.

This was initially added in [1] when the code was still in
AppArmorRestoreSecurityImageLabel (later moved) and even back then had
no further effect than described above.

[1]: https://libvirt.org/git/?p=libvirt.git;a=blob;f=src/security/security_apparmor.c;h=16de0f26f41689e0c50481120d9f8a59ba1f4073;hb=bbaecd6a8f15345bc822ab4b79eb0955986bb2fd#l487Reviewed-by: NCole Robinson <crobinso@redhat.com>
Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

While only used internally from libvirt the options still are misleading
enough to cause issues every now and then.
Group modes, options and an adding extra file and extend the wording of
the latter which had the biggest lack of clarity.
Both add a file to the end of the rules, but one re-generates the
rules from XML and the other keeps the existing rules as-is not
considering the XML content.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

When starting a domain without a CPU model specified in the domain XML,
QEMU will choose a default one. Which is fine unless the domain gets
migrated to another host because libvirt doesn't perform any CPU ABI
checks and the virtual CPU provided by QEMU on the destination host can
differ from the one on the source host.

With QEMU 4.2.0 we can probe for the default CPU model used by QEMU for
a particular machine type and store it in the domain XML. This way the
chosen CPU model is more visible to users and libvirt will make sure
the guest will see the exact same CPU after migration.

Architecture specific notes
- aarch64: We only set the default CPU for TCG domains as KVM requires
  explicit "-cpu host" to work.

- ppc64: The default CPU for KVM is "host" thanks to some hacks in QEMU,
  we will translate the default model to the model corresponding to the
  host CPU ("POWER8" on a Power8 host, "POWER9" on Power9 host, etc.).
  This is not a problem as the corresponding CPU model is in fact an
  alias for "host". This is probably not ideal, but it's not wrong and
  the default virtual CPU configured by libvirt is the same QEMU would
  use. TCG uses various CPU models depending on machine type and its
  version.

- s390x: The default CPU for KVM is "host" while TCG defaults to "qemu".

- x86_64: The default CPU model (qemu64) is not runnable on any host
  with KVM, but QEMU just disables unavailable features and starts
  happily.

https://bugzilla.redhat.com/show_bug.cgi?id=1598151
https://bugzilla.redhat.com/show_bug.cgi?id=1598162Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

To avoid mismatch between host and QEMU capabilities.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

QEMU 4.2.0 will report default CPU types used by each machine type and
we will want to start using it.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Almost all TCG query-machines replies match KVM. The only exceptions are
4.2.0 replies on s390x which differ in the reported default CPU type.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Some specifics of machine types may depend on the accelerator and thus
the data should be moved to virQEMUCapsAccel. The TCG machine types are
just copied from the ones probed for KVM to simplify the changes to
qemucapabilitiestest data files.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The function copies machine type data from one QEMU caps structure to
another.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

In preparation for making machine types dependent on the accelerator,
the <machine> elements are formatted between <cpu type='kvm'> and
<cpu type='tcg'>.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

All the code for formatting machine type data was moved to a standalone
virQEMUCapsFormatMachines function.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

All the code for loading machine type data was moved to a standalone
virQEMUCapsLoadMachines function.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

To avoid duplicating code which selects the right virQEMUCapsAccel data
to be filled during probing.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

It is a tiny wrapper around virQEMUCapsProbeQMPCPUDefinitions which will
soon get private parameters and thus it cannot be exposed outside
qemu_capabilities.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

And make it use virQEMUCapsGetAccel once rather than repeating the same
code in all functions called from virQEMUCapsFormatAccel.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

And make it use virQEMUCapsGetAccel once rather than repeating the same
code in all functions called from virQEMUCapsLoadAccel.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

It was very similar to virQEMUCapsGetAccel.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The function can be used to get the pointer to all data which depend on
the accelerator.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

This is container for capabilities data that depend on the accelerator.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The new functions are designed to load and format capabilities which
depend on the accelerator (host CPU expansion and CPU models).
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>