[BUG] Stack overflow error caused by fastjson2 serialization List

[PoppingSnack]

Stack overflow error caused by fastjson2 serialization List

Description

fastjson2 before v2.0.33 was discovered to contain a stack overflow via the List parameter.

Error Log

Exception in thread "main" java.lang.StackOverflowError
	at com.alibaba.fastjson2.writer.ObjectWriterProvider.getObjectWriter(ObjectWriterProvider.java:266)
	at com.alibaba.fastjson2.JSONWriter$Context.getObjectWriter(JSONWriter.java:1546)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:350)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)
	at com.alibaba.fastjson2.writer.ObjectWriterImplList.write(ObjectWriterImplList.java:371)

PoC

        <dependency>
            <groupId>com.alibaba.fastjson2</groupId>
            <artifactId>fastjson2</artifactId>
            <version>2.0.33</version>
        </dependency>

import com.alibaba.fastjson2.JSON;

import java.util.ArrayList;

public class PoC3 {

    public static void main(String[] args) {
        ArrayList<Object> list = new ArrayList<>();
        list.add(list);
        String jsonString = JSON.toJSONString(list);
        System.out.println(jsonString);
    }
}

Rectification Solution

1. Refer to the solution of jackson-databind: Add the depth variable to record the current parsing depth. If the parsing depth exceeds a certain threshold, an exception is thrown. (FasterXML/jackson-databind@fcfc499)

2. Refer to the GSON solution: Change the recursive processing on deeply nested arrays or JSON objects to stack+iteration processing.(（google/gson@2d01d6a20f39881c692977564c1ea591d9f39027）)

References

1. If the value in map is the map's self, the new new JSONObject(map) cause StackOverflowError which may lead to dos jettison-json/jettison#52
2. https://github.com/jettison-json/jettison/pull/53/files

[wenshao]

https://github.com/alibaba/fastjson2/releases/edit/2.0.34
问题已修复，请用新版本