virt-aa-helper: generate rules for nvdimm memory

nvdimm memory is backed by a path on the host. This currently works only via
hotplug where the AppArmor label is created via the domain label callbacks.

This adds the virt-aa-helper support for nvdimm memory devices to generate
rules for the needed paths from the initial guest definition as well.

Example in domain xml:
  <memory model='nvdimm'>
    <source>
      <path>/tmp/nvdimm-base</path>
    </source>
    <target>
     <size unit='KiB'>524288</size>
     <node>0</node>
    </target>
  </memory>
Works to start now and creates:
  "/tmp/nvdimm-base" rw,

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1757085Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

src/security/virt-aa-helper.c

@@ -1177,6 +1177,14 @@ get_files(vahControl * ctl)
         }
     }
 
+    for (i = 0; i < ctl->def->nmems; i++) {
+        if (ctl->def->mems[i] &&
+                ctl->def->mems[i]->model == VIR_DOMAIN_MEMORY_MODEL_NVDIMM) {
+            if (vah_add_file(&buf, ctl->def->mems[i]->nvdimmPath, "rw") != 0)
+                goto cleanup;
+        }
+    }
+
     if (ctl->def->virtType == VIR_DOMAIN_VIRT_KVM) {
         for (i = 0; i < ctl->def->nnets; i++) {
             virDomainNetDefPtr net = ctl->def->nets[i];

tests/virt-aa-helper-test

@@ -362,6 +362,9 @@ testme "0" "vnc socket" "-r -u $valid_uuid" "$test_xml"
 sed -e "s,###UUID###,$uuid,g" -e "s,###DISK###,$disk1,g" -e "s,</devices>,<input type='passthrough' bus='virtio'><source evdev='$disk2' /></input></devices>,g" "$template_xml" > "$test_xml"
 testme "0" "input dev passthrough" "-r -u $valid_uuid" "$test_xml"
 
+sed -e "s,###UUID###,$uuid,g" -e "s,###DISK###,$disk1,g" -e "s,<memory>524288</memory>,<memory>1048576</memory>,g" -e "s,</devices>,<memory model='nvdimm'><source><path>$disk2</path></source><target><size unit='KiB'>524288</size><node>0</node></target></memory></devices>,g" "$template_xml" > "$test_xml"
+testme "0" "nvdimm" "-r -u $valid_uuid" "$test_xml"
+
 testme "0" "help" "-h"
 
 echo "" >$output