diff --git a/source/libs/executor/src/scanoperator.c b/source/libs/executor/src/scanoperator.c
index 89340f2b85..c5d19981cf 100644
--- a/source/libs/executor/src/scanoperator.c
+++ b/source/libs/executor/src/scanoperator.c
@@ -327,7 +327,8 @@ void addTagPseudoColumnData(SReadHandle *pHandle, SExprInfo* pPseudoExpr, int32_
       for (int32_t i = 0; i < pBlock->info.rows; ++i) {
         colDataAppend(pColInfoData, i, data, (data == NULL));
       }
-      if(pColInfoData->info.type != TSDB_DATA_TYPE_JSON && IS_VAR_DATA_TYPE(((const STagVal *)p)->type) && data){
+      if(pColInfoData->info.type != TSDB_DATA_TYPE_JSON && p != NULL &&
+          IS_VAR_DATA_TYPE(((const STagVal *)p)->type) && data){
         taosMemoryFree(data);
       }
     }
diff --git a/source/libs/parser/src/parInsert.c b/source/libs/parser/src/parInsert.c
index 529e10be65..4cc3da5beb 100644
--- a/source/libs/parser/src/parInsert.c
+++ b/source/libs/parser/src/parInsert.c
@@ -2126,7 +2126,7 @@ static int32_t smlBuildTagRow(SArray* cols, SParsedDataColInfo* tags, SSchema* p
       val.nData = kv->length;
     }else if(pTagSchema->type == TSDB_DATA_TYPE_NCHAR){
       int32_t output = 0;
-      void *p = taosMemoryCalloc(1, kv->length * TSDB_NCHAR_SIZE);
+      void *p = taosMemoryCalloc(1, pTagSchema->bytes - VARSTR_HEADER_SIZE);
       if(p == NULL){
         code = TSDB_CODE_OUT_OF_MEMORY;
         goto end;