fix:[TD-25071] pSub is null & return wal not exist if no data

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

@@ -419,6 +419,9 @@ static int32_t mndProcessMqHbReq(SRpcMsg *pMsg) {
     mDebug("heartbeat report offset rows.%s:%s", pConsumer->cgroup, data->topicName);
 
     SMqSubscribeObj *pSub = mndAcquireSubscribe(pMnode, pConsumer->cgroup, data->topicName);
+    if(pSub == NULL){
+      continue;
+    }
     taosWLockLatch(&pSub->lock);
     SMqConsumerEp *pConsumerEp = taosHashGet(pSub->consumerHash, &consumerId, sizeof(int64_t));
     if(pConsumerEp){

source/libs/wal/src/walRead.c

@@ -82,6 +82,11 @@ int32_t walNextValidMsg(SWalReader *pReader) {
          ", applied index:%" PRId64", end index:%" PRId64,
          pReader->pWal->cfg.vgId, fetchVer, lastVer, committedVer, appliedVer, endVer);
 
+  if (fetchVer > endVer){
+    terrno = TSDB_CODE_WAL_LOG_NOT_EXIST;
+    return -1;
+  }
+
   while (fetchVer <= endVer) {
     if (walFetchHeadNew(pReader, fetchVer) < 0) {
       return -1;