diff --git a/source/libs/stream/src/streamBackendRocksdb.c b/source/libs/stream/src/streamBackendRocksdb.c
index 30a5bb76db..55b8365dbb 100644
--- a/source/libs/stream/src/streamBackendRocksdb.c
+++ b/source/libs/stream/src/streamBackendRocksdb.c
@@ -4825,7 +4825,7 @@ int32_t dbChkpGetDelta(SDbChkp* p, int64_t chkpId, SArray* list) {
           return terrno;
         }
 
-        tstrncpy(fname, name, strlen(name));
+        tstrncpy(fname, name, strlen(name) + 1);
         if (taosArrayPush(p->pAdd, &fname) == NULL) {
           taosMemoryFree(fname);
           TAOS_UNUSED(taosThreadRwlockUnlock(&p->rwLock));