If the starting point of the range request is greater than the maximum length of the content, the response status 416 shall be returned.

[masx200]

If the starting point of the range request is greater than the maximum length of the content, the response status 416 shall be returned.

GET / HTTP/1.1
Host: localhost:4000
Connection: keep-alive
Cache-Control: no-cache
sec-ch-ua: " Not;A Brand";v="99", "Microsoft Edge";v="91", "Chromium";v="91"
DNT: 1
accept-language: zh-CN,zh;q=0.9,en;q=0.8,en-GB;q=0.7,en-US;q=0.6
sec-ch-ua-mobile: ?0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36 Edg/91.0.864.54
accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
upgrade-insecure-requests: 1
if-none-match: "253b-oDUrS8IQyJRM9EiG2CmtiW6ahlM"
range: bytes=9999999-
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: cors
Sec-Fetch-Dest: empty
Referer: http://localhost:4000/
Accept-Encoding: identity

HTTP/1.1 206 Partial Content
Access-Control-Allow-Origin: *
Accept-Ranges: bytes
Vary: Origin, Accept-Encoding
Content-Type: text/html; charset=utf-8
Content-Length: -9990468
ETag: "253b-pRYhHemHVMhhBMOOkvWAjABIxIE"
Content-Range: bytes 9999999-9530/9531
Date: Tue, 22 Jun 2021 05:59:36 GMT
Connection: keep-alive
Keep-Alive: timeout=5

I found that some video player clients will send out requests for video files beyond the scope. E.g. PotPlayer

[masx200]

https://github.com/koajs/koa-range/blob/3d18e9f18e450a48e6464f4497e8b619e7310e14/index.js#L80

 if (len !== '*') {
    ctx.length = end - start + 1;
  }

Just make the following modifications.

    if (len !== "*") {
        let ctxlength = end - start + 1;
        if (ctxlength <= 0) {
            ctx.status = 416;
        }

        ctx.length = Math.max(0, ctxlength);
    }

[masx200]

https://github.com/masx200/koa-range/blob/efa08c6951a53cce9df70fc21690cbe5beb147dd/index.js#L87

[masx200]

https://github.com/koajs/koa-range/pull/23