From b0f7355d113f5f069f7993ab9c5997c34939a6bf Mon Sep 17 00:00:00 2001
From: Benguang Zhao <bgzhao@taosdata.com>
Date: Mon, 6 May 2024 16:57:22 +0800
Subject: [PATCH] enh: check snap begin index against commit index on leader

---
 source/libs/sync/src/syncSnapshot.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/source/libs/sync/src/syncSnapshot.c b/source/libs/sync/src/syncSnapshot.c
index 973eb8aaa5..8dab694975 100644
--- a/source/libs/sync/src/syncSnapshot.c
+++ b/source/libs/sync/src/syncSnapshot.c
@@ -1100,6 +1100,14 @@ static int32_t syncNodeOnSnapshotPrepRsp(SSyncNode *pSyncNode, SSyncSnapshotSend
   int32_t   code = -1;
   SSnapshot snapshot = {0};
 
+  if (pMsg->snapBeginIndex > pSyncNode->commitIndex) {
+    sSError(pSender,
+            "snapshot begin index is greater than commit index. snapBeginIndex:%" PRId64 ", commitIndex:%" PRId64,
+            pMsg->snapBeginIndex, pSyncNode->commitIndex);
+    terrno = TSDB_CODE_SYN_INVALID_SNAPSHOT_MSG;
+    return -1;
+  }
+
   taosThreadMutexLock(&pSender->pSndBuf->mutex);
   pSyncNode->pFsm->FpGetSnapshotInfo(pSyncNode->pFsm, &snapshot);