security: selinux: Take parent security label into account

Until now we ignored user-provided backing chains and while detecting
the code inherited labels of the parent device. With user provided
chains we should keep this functionality, so label of the parent image
in the backing chain will be applied if an image-specific label is not
present.

diff --git a/src/security/security_selinux.c b/src/security/security_selinux.c
index 66b3bbf1c5e3ea90696499dfd17874ed99238db3..ed1828a12f34f3e1921d9700c81802ed3a4d14eb 100644 (file)
--- a/src/security/security_selinux.c
+++ b/src/security/security_selinux.c
@@ -1597,6 +1597,7 @@ virSecuritySELinuxSetImageLabelInternal(virSecurityManagerPtr mgr,
     virSecuritySELinuxDataPtr data = virSecurityManagerGetPrivateData(mgr);
     virSecurityLabelDefPtr secdef;
     virSecurityDeviceLabelDefPtr disk_seclabel;
+    virSecurityDeviceLabelDefPtr parent_seclabel = NULL;
     int ret;
 
     if (!src->path || !virStorageSourceIsLocalStorage(src))
@@ -1608,12 +1609,20 @@ virSecuritySELinuxSetImageLabelInternal(virSecurityManagerPtr mgr,
 
     disk_seclabel = virStorageSourceGetSecurityLabelDef(src,
                                                         SECURITY_SELINUX_NAME);
+    if (parent)
+        parent_seclabel = virStorageSourceGetSecurityLabelDef(parent,
+                                                              SECURITY_SELINUX_NAME);
 
-    if (disk_seclabel && !disk_seclabel->relabel)
-        return 0;
+    if (disk_seclabel && (!disk_seclabel->relabel || disk_seclabel->label)) {
+        if (!disk_seclabel->relabel)
+            return 0;
 
-    if (disk_seclabel && disk_seclabel->relabel && disk_seclabel->label) {
         ret = virSecuritySELinuxSetFilecon(mgr, src->path, disk_seclabel->label);
+    } else if (parent_seclabel && (!parent_seclabel->relabel || parent_seclabel->label)) {
+        if (!parent_seclabel->relabel)
+            return 0;
+
+        ret = virSecuritySELinuxSetFilecon(mgr, src->path, parent_seclabel->label);
     } else if (!parent || parent == src) {
         if (src->shared) {
             ret = virSecuritySELinuxSetFileconOptional(mgr,