From 982184d57fff654c1cccf0d4a4a5d1631058819d Mon Sep 17 00:00:00 2001
From: Michal Privoznik <mprivozn@redhat.com>
Date: Mon, 20 Nov 2023 04:49:53 +0100
Subject: [PATCH 2/7] vbox_snapshot_conf: Parse XMLs without net access
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When working with VirtualBox's snapshots, the snapshot XML is
firstly parsed, stored in memory (with some parts being stored as
verbatim XML snippets, strings), requested changes are made and
then this modified XML is formatted via
virVBoxSnapshotConfSaveVboxFile() which calls
xmlParseInNodeContext() to format those previously stored XML
snippets.

The first parse of whole VirtualBox snapshot file is done using
virXMLParse() (in virVBoxSnapshotConfLoadVboxFile()) and thus
with XML_PARSE_NONET specified.

But those ad-hoc parsings when formatting the XML back pass zero
flags mask: xmlParseInNodeContext(..., options = 0, ...);

This is potentially dangerous.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
(cherry picked from commit d8cb1cd50c608eb647fcb17c4347a2e9d5004e8d)
---
 src/vbox/vbox_snapshot_conf.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/vbox/vbox_snapshot_conf.c b/src/vbox/vbox_snapshot_conf.c
index 84f7aceac2..467255f77f 100644
--- a/src/vbox/vbox_snapshot_conf.c
+++ b/src/vbox/vbox_snapshot_conf.c
@@ -369,6 +369,7 @@ virVBoxSnapshotConfSerializeSnapshot(xmlNodePtr node,
     int firstRegexResult = 0;
     g_auto(GStrv) secondRegex = NULL;
     int secondRegexResult = 0;
+    const int parseFlags = XML_PARSE_NONET;
 
     uuid = g_strdup_printf("{%s}", snapshot->uuid);
 
@@ -406,7 +407,7 @@ virVBoxSnapshotConfSerializeSnapshot(xmlNodePtr node,
     parseError = xmlParseInNodeContext(node,
                                        snapshot->hardware,
                                        (int)strlen(snapshot->hardware),
-                                       0,
+                                       parseFlags,
                                        &hardwareNode);
     if (parseError != XML_ERR_OK) {
         virReportError(VIR_ERR_XML_ERROR, "%s",
@@ -418,7 +419,7 @@ virVBoxSnapshotConfSerializeSnapshot(xmlNodePtr node,
     /* storageController */
     if (xmlParseInNodeContext(node, snapshot->storageController,
                               (int)strlen(snapshot->storageController),
-                              0,
+                              parseFlags,
                               &storageControllerNode) != XML_ERR_OK) {
         virReportError(VIR_ERR_XML_ERROR, "%s",
                        _("Unable to add the snapshot storageController"));
@@ -944,6 +945,7 @@ virVBoxSnapshotConfSaveVboxFile(virVBoxSnapshotConfMachine *machine,
     int firstRegexResult = 0;
     g_auto(GStrv) secondRegex = NULL;
     int secondRegexResult = 0;
+    const int parseFlags = XML_PARSE_NONET;
 
     if (machine == NULL) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
@@ -1051,7 +1053,7 @@ virVBoxSnapshotConfSaveVboxFile(virVBoxSnapshotConfMachine *machine,
         parseError = xmlParseInNodeContext(mediaRegistryNode,
                               machine->mediaRegistry->otherMedia[i],
                               (int)strlen(machine->mediaRegistry->otherMedia[i]),
-                              0,
+                              parseFlags,
                               &cur);
         if (parseError != XML_ERR_OK) {
             virReportError(VIR_ERR_XML_ERROR, "%s",
@@ -1071,7 +1073,7 @@ virVBoxSnapshotConfSaveVboxFile(virVBoxSnapshotConfMachine *machine,
     parseError = xmlParseInNodeContext(machineNode,
                                        machine->hardware,
                                        (int)strlen(machine->hardware),
-                                       0,
+                                       parseFlags,
                                        &cur);
     if (parseError != XML_ERR_OK) {
         virReportError(VIR_ERR_XML_ERROR, "%s",
@@ -1084,7 +1086,7 @@ virVBoxSnapshotConfSaveVboxFile(virVBoxSnapshotConfMachine *machine,
         parseError = xmlParseInNodeContext(xmlDocGetRootElement(xml),
                                            machine->extraData,
                                            (int)strlen(machine->extraData),
-                                           0,
+                                           parseFlags,
                                            &cur);
         if (parseError != XML_ERR_OK) {
             virReportError(VIR_ERR_XML_ERROR, "%s",
@@ -1097,7 +1099,7 @@ virVBoxSnapshotConfSaveVboxFile(virVBoxSnapshotConfMachine *machine,
     parseError = xmlParseInNodeContext(machineNode,
                                        machine->storageController,
                                        (int)strlen(machine->storageController),
-                                       0,
+                                       parseFlags,
                                        &cur);
     if (parseError != XML_ERR_OK) {
         virReportError(VIR_ERR_XML_ERROR, "%s",
-- 
2.43.0