qemu: block copy: Forbid block copy to relative paths

Similarly to 29bb066915 forbid paths used with blockjobs to be relative.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1300177

src/conf/snapshot_conf.c

@@ -170,9 +170,7 @@ virDomainSnapshotDiskDefParseXML(xmlNodePtr node,
     }
 
     /* validate that the passed path is absolute */
-    if (virStorageSourceIsLocalStorage(def->src) &&
-        def->src->path &&
-        def->src->path[0] != '/') {
+    if (virStorageSourceIsRelative(def->src)) {
         virReportError(VIR_ERR_XML_ERROR,
                        _("disk snapshot image path '%s' must be absolute"),
                        def->src->path);

src/libvirt_private.syms

@@ -2455,6 +2455,7 @@ virStorageSourceInitChainElement;
 virStorageSourceIsBlockLocal;
 virStorageSourceIsEmpty;
 virStorageSourceIsLocalStorage;
+virStorageSourceIsRelative;
 virStorageSourceNewFromBacking;
 virStorageSourceNewFromBackingAbsolute;
 virStorageSourceParseRBDColonString;

src/qemu/qemu_driver.c

@@ -16665,6 +16665,12 @@ qemuDomainBlockCopyCommon(virDomainObjPtr vm,
     priv = vm->privateData;
     cfg = virQEMUDriverGetConfig(driver);
 
+    if (virStorageSourceIsRelative(mirror)) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("absolute path must be used as block copy target"));
+        goto cleanup;
+    }
+
     if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
         goto cleanup;
 

src/util/virstoragefile.c

@@ -3672,3 +3672,34 @@ virStorageFileCheckCompat(const char *compat)
     virStringListFree(version);
     return ret;
 }
+
+
+/**
+ * virStorageSourceIsRelative:
+ * @src: storage source to check
+ *
+ * Returns true if given storage source definition is a relative path.
+ */
+bool
+virStorageSourceIsRelative(virStorageSourcePtr src)
+{
+    virStorageType actual_type = virStorageSourceGetActualType(src);
+
+    if (!src->path)
+        return false;
+
+    switch (actual_type) {
+    case VIR_STORAGE_TYPE_FILE:
+    case VIR_STORAGE_TYPE_BLOCK:
+    case VIR_STORAGE_TYPE_DIR:
+        return src->path[0] != '/';
+
+    case VIR_STORAGE_TYPE_NETWORK:
+    case VIR_STORAGE_TYPE_VOLUME:
+    case VIR_STORAGE_TYPE_NONE:
+    case VIR_STORAGE_TYPE_LAST:
+        return false;
+    }
+
+    return false;
+}

src/util/virstoragefile.h

@@ -388,4 +388,6 @@ int virStorageFileCheckCompat(const char *compat);
 
 virStorageSourcePtr virStorageSourceNewFromBackingAbsolute(const char *path);
 
+bool virStorageSourceIsRelative(virStorageSourcePtr src);
+
 #endif /* __VIR_STORAGE_FILE_H__ */