Merge pull request #22704 from taosdata/fix/TD-26105

fix(stream): add null ptr check.

source/dnode/mnode/impl/src/mndStream.c

@@ -2315,9 +2315,13 @@ int32_t mndProcessStreamHb(SRpcMsg *pReq) {
   for (int32_t i = 0; i < req.numOfTasks; ++i) {
     STaskStatusEntry *p = taosArrayGet(req.pTaskStatus, i);
     int64_t           k[2] = {p->streamId, p->taskId};
-    int32_t           index = *(int32_t *)taosHashGet(execNodeList.pTaskMap, &k, sizeof(k));
 
-    STaskStatusEntry *pStatusEntry = taosArrayGet(execNodeList.pTaskList, index);
+    int32_t *index = taosHashGet(execNodeList.pTaskMap, &k, sizeof(k));
+    if (index == NULL) {
+      continue;
+    }
+
+    STaskStatusEntry *pStatusEntry = taosArrayGet(execNodeList.pTaskList, *index);
     pStatusEntry->status = p->status;
     if (p->status != TASK_STATUS__NORMAL) {
       mDebug("received s-task:0x%x not in ready status:%s", p->taskId, streamGetTaskStatusStr(p->status));