From 03c33e77aa71efc1c7d287d8f6fc707dc24175f1 Mon Sep 17 00:00:00 2001
From: Jinqing Kuang <kuangjinqingcn@gmail.com>
Date: Fri, 27 Sep 2024 13:34:50 +0800
Subject: [PATCH] fix(query)[TD-32353]. Fix error handling during tag scan

Correct the row count in the result data block when the tag scan
tolerates partial errors. This prevents upper-layer operators from
accessing invalid memory address.
---
 source/libs/executor/src/scanoperator.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/source/libs/executor/src/scanoperator.c b/source/libs/executor/src/scanoperator.c
index a2e2dc9b98..c13535b7f6 100644
--- a/source/libs/executor/src/scanoperator.c
+++ b/source/libs/executor/src/scanoperator.c
@@ -4294,13 +4294,13 @@ _error:
   return code;
 }
 
-static int32_t doTagScanOneTable(SOperatorInfo* pOperator, const SSDataBlock* pRes, int32_t count, SMetaReader* mr,
-                                 SStorageAPI* pAPI) {
+static int32_t doTagScanOneTable(SOperatorInfo* pOperator, SSDataBlock* pRes, SMetaReader* mr, SStorageAPI* pAPI) {
   int32_t        code = TSDB_CODE_SUCCESS;
   int32_t        lino = 0;
   SExecTaskInfo* pTaskInfo = pOperator->pTaskInfo;
   STagScanInfo*  pInfo = pOperator->info;
   SExprInfo*     pExprInfo = &pOperator->exprSupp.pExprInfo[0];
+  int32_t        count = pRes->info.rows;
 
   STableKeyInfo* item = tableListGetInfo(pInfo->pTableListInfo, pInfo->curPos);
   if (!item) {
@@ -4360,6 +4360,8 @@ _end:
   if (code != TSDB_CODE_SUCCESS) {
     qError("%s failed at line %d since %s", __func__, lino, tstrerror(code));
     pTaskInfo->code = code;
+  } else {
+    pRes->info.rows++;
   }
 
   return code;
@@ -4715,26 +4717,23 @@ static int32_t doTagScanFromMetaEntryNext(SOperatorInfo* pOperator, SSDataBlock*
     return code;
   }
 
-  int32_t     count = 0;
   SMetaReader mr = {0};
   pAPI->metaReaderFn.initReader(&mr, pInfo->readHandle.vnode, META_READER_LOCK, &pAPI->metaFn);
+  pRes->info.rows = 0;
 
-  while (pInfo->curPos < size && count < pOperator->resultInfo.capacity) {
-    code = doTagScanOneTable(pOperator, pRes, count, &mr, &pTaskInfo->storageAPI);
+  while (pInfo->curPos < size && pRes->info.rows < pOperator->resultInfo.capacity) {
+    code = doTagScanOneTable(pOperator, pRes, &mr, &pTaskInfo->storageAPI);
     if (code != TSDB_CODE_OUT_OF_MEMORY) {
       // ignore other error
       code = TSDB_CODE_SUCCESS;
     }
     QUERY_CHECK_CODE(code, lino, _end);
 
-    ++count;
     if (++pInfo->curPos >= size) {
       setOperatorCompleted(pOperator);
     }
   }
 
-  pRes->info.rows = count;
-
   pAPI->metaReaderFn.clearReader(&mr);
   bool bLimitReached = applyLimitOffset(&pInfo->limitInfo, pRes, pTaskInfo);
   if (bLimitReached) {