Merge pull request #17319 from taosdata/fix/sync-timer

fix(sync): enqueue timer msg

source/dnode/vnode/src/vnd/vnodeSync.c

@@ -474,6 +474,10 @@ int32_t vnodeProcessSyncMsg(SVnode *pVnode, SRpcMsg *pMsg, SRpcMsg **pRsp) {
 }
 
 static int32_t vnodeSyncEqMsg(const SMsgCb *msgcb, SRpcMsg *pMsg) {
+  if (msgcb == NULL) {
+    return -1;
+  }
+
   int32_t code = tmsgPutToQueue(msgcb, SYNC_QUEUE, pMsg);
   if (code != 0) {
     rpcFreeCont(pMsg->pCont);