增加对len的限制

Signed-off-by: srr101 <songruirui1@huawei.com>

interfaces/inner_api/dataobs_manager/include/dataobs_mgr_changeinfo.h

@@ -37,6 +37,7 @@ struct ChangeInfo {
     mutable std::list<Uri> uris_ = {};
     const void *data_ = nullptr;
     uint32_t size_ = 0;
+    static constexpr int LIST_MAX_COUNT = 3000;
 };
 } // namespace AAFwk
 } // namespace OHOS

services/dataobsmgr/src/dataobs_mgr_changeinfo.cpp

@@ -53,6 +53,9 @@ bool ChangeInfo::Unmarshalling(ChangeInfo &output, MessageParcel &parcel)
     if (!parcel.ReadUint32(len)) {
         return false;
     }
+    if (len > LIST_MAX_COUNT) {
+        return false;
+    }
 
     std::list<Uri> uris;
     for (uint32_t i = 0; i < len; i++) {