diff --git a/source/libs/executor/src/executorMain.c b/source/libs/executor/src/executorMain.c
index 354f4d8752..d4d8696aba 100644
--- a/source/libs/executor/src/executorMain.c
+++ b/source/libs/executor/src/executorMain.c
@@ -133,6 +133,7 @@ int32_t qExecTask(qTaskInfo_t tinfo, SSDataBlock** pRes, uint64_t *useconds) {
   if (ret != TSDB_CODE_SUCCESS) {
     publishQueryAbortEvent(pTaskInfo, ret);
     pTaskInfo->code = ret;
+    cleanUpUdfs();
     qDebug("%s task abort due to error/cancel occurs, code:%s", GET_TASKID(pTaskInfo),
            tstrerror(pTaskInfo->code));
     return pTaskInfo->code;
diff --git a/source/libs/function/src/tudf.c b/source/libs/function/src/tudf.c
index 068998e469..5f20d2e50a 100644
--- a/source/libs/function/src/tudf.c
+++ b/source/libs/function/src/tudf.c
@@ -1364,9 +1364,12 @@ void releaseUdfFuncHandle(char* udfName) {
   SUdfcFuncStub key = {0};
   strcpy(key.udfName, udfName);
   SUdfcFuncStub *foundStub = taosArraySearch(gUdfdProxy.udfStubs, &key, compareUdfcFuncSub, TD_EQ);
-  ASSERT(foundStub);
-  --foundStub->refCount;
-  ASSERT(foundStub->refCount>=0);
+  if (!foundStub) {
+    return;
+  }
+  if (foundStub->refCount > 0) {
+    --foundStub->refCount;
+  }
   uv_mutex_unlock(&gUdfdProxy.udfStubsMutex);
 }
 
@@ -1377,7 +1380,7 @@ int32_t cleanUpUdfs() {
   while (i < taosArrayGetSize(gUdfdProxy.udfStubs)) {
     SUdfcFuncStub *stub = taosArrayGet(gUdfdProxy.udfStubs, i);
     if (stub->refCount == 0) {
-      fnInfo("tear down udf. udf name: %s, handle: %p", stub->udfName, stub->handle);
+      fnInfo("tear down udf. udf name: %s, handle: %p, ref count: %d", stub->udfName, stub->handle, stub->refCount);
       doTeardownUdf(stub->handle);
     } else {
       fnInfo("udf still in use. udf name: %s, ref count: %d, last ref time: %"PRId64", handle: %p",
@@ -1530,12 +1533,15 @@ int32_t callUdfScalarFunc(char *udfName, SScalarParam *input, int32_t numOfCols,
   }
   SUdfcUvSession *session = handle;
   code = doCallUdfScalarFunc(handle, input, numOfCols, output);
-  if (session->outputType != output->columnData->info.type
-      || session->outputLen != output->columnData->info.bytes) {
-    fnError("udfc scalar function calculate error, session type: %d(%d), output type: %d(%d)",
-            session->outputType, session->outputLen,
-            output->columnData->info.type, output->columnData->info.bytes);
+  if (output->columnData == NULL) {
+    fnError("udfc scalar function calculate error. no column data");
     code = TSDB_CODE_UDF_INVALID_OUTPUT_TYPE;
+  } else {
+    if (session->outputType != output->columnData->info.type || session->outputLen != output->columnData->info.bytes) {
+      fnError("udfc scalar function calculate error. type mismatch. session type: %d(%d), output type: %d(%d)", session->outputType,
+              session->outputLen, output->columnData->info.type, output->columnData->info.bytes);
+      code = TSDB_CODE_UDF_INVALID_OUTPUT_TYPE;
+    }
   }
   releaseUdfFuncHandle(udfName);
   return code;
@@ -1565,7 +1571,7 @@ int32_t doTeardownUdf(UdfcFuncHandle handle) {
 
   fnInfo("tear down udf. udf name: %s, udf func handle: %p", session->udfName, handle);
 
-  taosMemoryFree(task->session);
+  taosMemoryFree(session);
   taosMemoryFree(task);
 
   return err;
@@ -1573,7 +1579,6 @@ int32_t doTeardownUdf(UdfcFuncHandle handle) {
 
 //memory layout |---SUdfAggRes----|-----final result-----|---inter result----|
 typedef struct SUdfAggRes {
-  SUdfcUvSession *session;
   int8_t finalResNum;
   int8_t interResNum;
   char* finalResBuf;
@@ -1606,7 +1611,6 @@ bool udfAggInit(struct SqlFunctionCtx *pCtx, struct SResultRowEntryInfo* pResult
   udfRes->finalResBuf = (char*)udfRes + sizeof(SUdfAggRes);
   udfRes->interResBuf = (char*)udfRes + sizeof(SUdfAggRes) + session->outputLen;
 
-  udfRes->session = (SUdfcUvSession *)handle;
   SUdfInterBuf buf = {0};
   if ((udfCode = doCallUdfAggInit(handle, &buf)) != 0) {
     fnError("udfAggInit error. step doCallUdfAggInit. udf code: %d", udfCode);
@@ -1621,22 +1625,26 @@ bool udfAggInit(struct SqlFunctionCtx *pCtx, struct SResultRowEntryInfo* pResult
     releaseUdfFuncHandle(pCtx->udfName);
     return false;
   }
+  releaseUdfFuncHandle(pCtx->udfName);
   freeUdfInterBuf(&buf);
   return true;
 }
 
 int32_t udfAggProcess(struct SqlFunctionCtx *pCtx) {
-  SInputColumnInfoData* pInput = &pCtx->input;
-  int32_t numOfCols = pInput->numOfInputCols;
-
-  SUdfAggRes* udfRes = (SUdfAggRes *)GET_ROWCELL_INTERBUF(GET_RES_INFO(pCtx));
-  SUdfcUvSession *session = udfRes->session;
-  if (session == NULL) {
-    return TSDB_CODE_UDF_NO_FUNC_HANDLE;
+  int32_t udfCode = 0;
+  UdfcFuncHandle handle = 0;
+  if ((udfCode = acquireUdfFuncHandle((char *)pCtx->udfName, &handle)) != 0) {
+    fnError("udfAggProcess  error. step acquireUdfFuncHandle. udf code: %d", udfCode);
+    return udfCode;
   }
+
+  SUdfcUvSession *session = handle;
+  SUdfAggRes* udfRes = (SUdfAggRes *)GET_ROWCELL_INTERBUF(GET_RES_INFO(pCtx));
   udfRes->finalResBuf = (char*)udfRes + sizeof(SUdfAggRes);
   udfRes->interResBuf = (char*)udfRes + sizeof(SUdfAggRes) + session->outputLen;
 
+  SInputColumnInfoData* pInput = &pCtx->input;
+  int32_t numOfCols = pInput->numOfInputCols;
   int32_t start = pInput->startRowIndex;
   int32_t numOfRows = pInput->numOfRows;
 
@@ -1664,7 +1672,7 @@ int32_t udfAggProcess(struct SqlFunctionCtx *pCtx) {
                         .numOfResult = udfRes->interResNum};
   SUdfInterBuf newState = {0};
 
-  int32_t udfCode = doCallUdfAggProcess(session, inputBlock, &state, &newState);
+  udfCode = doCallUdfAggProcess(session, inputBlock, &state, &newState);
   if (udfCode != 0) {
     fnError("udfAggProcess error. code: %d", udfCode);
     newState.numOfResult = 0;
@@ -1684,19 +1692,21 @@ int32_t udfAggProcess(struct SqlFunctionCtx *pCtx) {
   blockDataDestroy(inputBlock);
   taosArrayDestroy(tempBlock.pDataBlock);
 
-  if (udfCode != 0) {
-    releaseUdfFuncHandle(pCtx->udfName);
-  }
+  releaseUdfFuncHandle(pCtx->udfName);
   freeUdfInterBuf(&newState);
   return udfCode;
 }
 
 int32_t udfAggFinalize(struct SqlFunctionCtx *pCtx, SSDataBlock* pBlock) {
-  SUdfAggRes* udfRes = (SUdfAggRes *)GET_ROWCELL_INTERBUF(GET_RES_INFO(pCtx));
-  SUdfcUvSession *session = udfRes->session;
-  if (session == NULL) {
-    return TSDB_CODE_UDF_NO_FUNC_HANDLE;
+  int32_t udfCode = 0;
+  UdfcFuncHandle handle = 0;
+  if ((udfCode = acquireUdfFuncHandle((char *)pCtx->udfName, &handle)) != 0) {
+    fnError("udfAggProcess  error. step acquireUdfFuncHandle. udf code: %d", udfCode);
+    return udfCode;
   }
+
+  SUdfcUvSession *session = handle;
+  SUdfAggRes* udfRes = (SUdfAggRes *)GET_ROWCELL_INTERBUF(GET_RES_INFO(pCtx));
   udfRes->finalResBuf = (char*)udfRes + sizeof(SUdfAggRes);
   udfRes->interResBuf = (char*)udfRes + sizeof(SUdfAggRes) + session->outputLen;