File pacemaker#3292-0002-Low-libcrmcommon-fix-NULL-dereference-in-expand_idre.patch of Package pacemaker.38495

From c5715a0aaa8c8e4900df5292f9d0e5236cc86050 Mon Sep 17 00:00:00 2001
From: Ken Gaillot <kgaillot@redhat.com>
Date: Thu, 14 Dec 2023 15:53:41 -0600
Subject: [PATCH] Low: libcrmcommon: fix NULL dereference in expand_idref()

... detected by static analysis. Also, rename variables and reformat for
readability.
---
 lib/common/xml.c | 36 ++++++++++++++++++------------------
 1 file changed, 18 insertions(+), 18 deletions(-)

Index: pacemaker-2.1.5+20221208.a3f44794f/lib/common/xml.c
===================================================================
--- pacemaker-2.1.5+20221208.a3f44794f.orig/lib/common/xml.c
+++ pacemaker-2.1.5+20221208.a3f44794f/lib/common/xml.c
@@ -3001,34 +3001,32 @@ crm_xml_cleanup(void)
 xmlNode *
 expand_idref(xmlNode * input, xmlNode * top)
 {
-    const char *tag = NULL;
+    char *xpath = NULL;
     const char *ref = NULL;
-    xmlNode *result = input;
+    xmlNode *result = NULL;
 
-    if (result == NULL) {
+    if (input == NULL) {
         return NULL;
-
-    } else if (top == NULL) {
-        top = input;
     }
 
-    tag = crm_element_name(result);
-    ref = crm_element_value(result, XML_ATTR_IDREF);
-
-    if (ref != NULL) {
-        char *xpath_string = crm_strdup_printf("//%s[@id='%s']", tag, ref);
+    ref = crm_element_value(input, XML_ATTR_IDREF);
+    if (ref == NULL) {
+        return input;
+    }
 
-        result = get_xpath_object(xpath_string, top, LOG_DEBUG);
-        if (result == NULL) { // Not possible with schema validation enabled
-            char *nodePath = (char *)xmlGetNodePath(top);
+    if (top == NULL) {
+        top = input;
+    }
 
-            pcmk__config_err("Ignoring invalid %s configuration: "
-                             XML_ATTR_IDREF " '%s' does not reference "
-                             "a valid object", result->name, ref);
-            free(nodePath);
-        }
-        free(xpath_string);
+    xpath = crm_strdup_printf("//%s[@" XML_ATTR_ID "='%s']", input->name, ref);
+    result = get_xpath_object(xpath, top, LOG_DEBUG);
+    if (result == NULL) { // Not possible with schema validation enabled
+        pcmk__config_err("Ignoring invalid %s configuration: "
+                         XML_ATTR_IDREF " '%s' does not reference "
+                         "a valid object " CRM_XS " xpath=%s",
+                         input->name, ref, xpath);
     }
+    free(xpath);
     return result;
 }