From 47f8209a9d9727586da339d6e870326d2680adfb Mon Sep 17 00:00:00 2001
From: Ken Gaillot <kgaillot@redhat.com>
Date: Dec 15 2020 18:02:10 +0000
Subject: Low: pacemakerd: check client for NULL before using it


... to guard against bugs in client tracking

---

diff --git a/daemons/pacemakerd/pacemakerd.c b/daemons/pacemakerd/pacemakerd.c
index c888b73..b8bed63 100644
--- a/daemons/pacemakerd/pacemakerd.c
+++ b/daemons/pacemakerd/pacemakerd.c
@@ -568,9 +568,12 @@ pcmk_ipc_dispatch(qb_ipcs_connection_t * qbc, void *data, size_t size)
     uint32_t id = 0;
     uint32_t flags = 0;
     const char *task = NULL;
+    xmlNode *msg = NULL;
     pcmk__client_t *c = pcmk__find_client(qbc);
-    xmlNode *msg = pcmk__client_data2xml(c, data, &id, &flags);
 
+    CRM_CHECK(c != NULL, return 0);
+
+    msg = pcmk__client_data2xml(c, data, &id, &flags);
     pcmk__ipc_send_ack(c, id, flags, "ack");
     if (msg == NULL) {
         return 0;