From af566a030c4a70ed037eda075a4c09f14732482b Mon Sep 17 00:00:00 2001
Message-Id: <af566a030c4a70ed037eda075a4c09f14732482b@dist-git>
From: Cole Robinson <crobinso@redhat.com>
Date: Wed, 12 Aug 2015 10:47:16 +0200
Subject: [PATCH] domain: Fix crash if trying to live update disk <serial>

https://bugzilla.redhat.com/show_bug.cgi?id=1007228

If you pass <disk><serial> XML to UpdateDevice, and the original device
didn't have a <serial> block, libvirtd crashes trying to read the original
NULL serial string.

Use _NULLABLE string comparisons to avoid the crash. A couple other
properties needed the change too.

(cherry picked from commit c7790408d7e16b1ad00a690433d9310f104994f7)
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/conf/domain_conf.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index aa1b860..8784367 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5783,28 +5783,28 @@ virDomainDiskDiffersSourceOnly(virDomainDiskDefPtr disk,
 
     CHECK_EQ(transient, "transient", true);
 
-    if (disk->serial && STRNEQ(disk->serial, orig_disk->serial)) {
+    if (disk->serial && STRNEQ_NULLABLE(disk->serial, orig_disk->serial)) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
                        _("cannot modify field '%s' of the disk"),
                        "serial");
         return false;
     }
 
-    if (disk->wwn && STRNEQ(disk->wwn, orig_disk->wwn)) {
+    if (disk->wwn && STRNEQ_NULLABLE(disk->wwn, orig_disk->wwn)) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
                        _("cannot modify field '%s' of the disk"),
                        "wwn");
         return false;
     }
 
-    if (disk->vendor && STRNEQ(disk->vendor, orig_disk->vendor)) {
+    if (disk->vendor && STRNEQ_NULLABLE(disk->vendor, orig_disk->vendor)) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
                        _("cannot modify field '%s' of the disk"),
                        "vendor");
         return false;
     }
 
-    if (disk->product && STRNEQ(disk->product, orig_disk->product)) {
+    if (disk->product && STRNEQ_NULLABLE(disk->product, orig_disk->product)) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
                        _("cannot modify field '%s' of the disk"),
                        "product");
-- 
2.5.0