diff --git a/source/libs/parser/src/parInsertSml.c b/source/libs/parser/src/parInsertSml.c
index 0bb6d90fa9..6fe72beea6 100644
--- a/source/libs/parser/src/parInsertSml.c
+++ b/source/libs/parser/src/parInsertSml.c
@@ -189,14 +189,23 @@ int32_t smlBuildCol(STableDataCxt* pTableCxt, SSchema* schema, void* data, int32
   SSchema* pColSchema = schema + index;
   SColVal* pVal = taosArrayGet(pTableCxt->pValues, index);
   SSmlKv*  kv = (SSmlKv*)data;
+  if(kv->keyLen != strlen(pColSchema->name) || memcmp(kv->key, pColSchema->name, kv->keyLen) != 0){
+    ret = TSDB_CODE_SML_INVALID_DATA;
+    goto end;
+  }
   if (kv->type == TSDB_DATA_TYPE_NCHAR) {
     int32_t len = 0;
-    char*   pUcs4 = taosMemoryCalloc(1, pColSchema->bytes - VARSTR_HEADER_SIZE);
+    int64_t size = pColSchema->bytes - VARSTR_HEADER_SIZE;
+    if(size <= 0){
+      ret = TSDB_CODE_SML_INVALID_DATA;
+      goto end;
+    }
+    char*   pUcs4 = taosMemoryCalloc(1, size);
     if (NULL == pUcs4) {
       ret = TSDB_CODE_OUT_OF_MEMORY;
       goto end;
     }
-    if (!taosMbsToUcs4(kv->value, kv->length, (TdUcs4*)pUcs4, pColSchema->bytes - VARSTR_HEADER_SIZE, &len)) {
+    if (!taosMbsToUcs4(kv->value, kv->length, (TdUcs4*)pUcs4, size, &len)) {
       if (errno == E2BIG) {
         ret = TSDB_CODE_PAR_VALUE_TOO_LONG;
         goto end;
diff --git a/tests/system-test/2-query/sml.py b/tests/system-test/2-query/sml.py
index 594817113c..d5439d05de 100644
--- a/tests/system-test/2-query/sml.py
+++ b/tests/system-test/2-query/sml.py
@@ -88,6 +88,9 @@ class TDTestCase:
         tdSql.query(f"select * from {dbname}.macylr")
         tdSql.checkRows(2)
 
+        tdSql.query(f"select * from {dbname}.qelhxo")
+        tdSql.checkRows(5)
+
         tdSql.query(f"desc {dbname}.macylr")
         tdSql.checkRows(25)
         return
diff --git a/utils/test/c/sml_test.c b/utils/test/c/sml_test.c
index 720245d518..30d0ab27d8 100644
--- a/utils/test/c/sml_test.c
+++ b/utils/test/c/sml_test.c
@@ -302,7 +302,7 @@ int sml_16384_Test() {
   if(code) return code;
 
   const char *sql1[] = {
-      "qelhxo,id=pnnqhsa,t0=t,t1=127i8 c0=f,c1=127i8,c11=L\"ncharColValue\",c10=t 1626006833639000000",
+      "qelhxo,id=pnnqhsa,t0=t,t1=127i8 c0=f,c1=127i8,c11=L\"ncharColValue\",c10=t 1626006833631000000",
   };
   pRes = taos_schemaless_insert(taos, (char **)sql1, 1, TSDB_SML_LINE_PROTOCOL, 0);
   printf("%s result:%s\n", __FUNCTION__, taos_errstr(pRes));
@@ -866,7 +866,7 @@ int sml_19221_Test() {
   taos_free_result(pRes);
 
   const char *sql[] = {
-      "qelhxo,id=pnnqhsa,t0=t,t1=127i8 c11=L\"ncharColValue\",c0=t,c1=127i8 1626006833639000000\nqelhxo,id=pnnhsa,t0=t,t1=127i8 c11=L\"ncharColValue\",c0=t,c1=127i8 1626006833639000000\n#comment\nqelhxo,id=pnqhsa,t0=t,t1=127i8 c11=L\"ncharColValue\",c0=t,c1=127i8 1626006833639000000",
+      "qelhxo,id=pnnqhsa,t0=t,t1=127i8 c11=L\"ncharColValue\",c0=t,c1=127i8 1626006833632000000\nqelhxo,id=pnnhsa,t0=t,t1=127i8 c11=L\"ncharColValue\",c0=t,c1=127i8 1626006833633000000\n#comment\nqelhxo,id=pnqhsa,t0=t,t1=127i8 c11=L\"ncharColValue\",c0=t,c1=127i8 1626006833634000000",
   };
 
   pRes = taos_query(taos, "use sml_db");