Corner case "_devices[device_id].hit" erroneously set true in "_handleSetup(...)". - Githubissues

vintlabs / fauxmoESP

Add voice control of your ESP32 and ESP8266 devices using Amazon Alexa

MIT License

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Corner case "_devices[device_id].hit" erroneously set true in "_handleSetup(...)". #48

Closed pvint closed 5 years ago

pvint commented 6 years ago

Original report by M Hightower (Bitbucket: mhightower83, GitHub: mhightower83).

First, thank you for the fine work you do on fauxmoESP and ESPurna.

This issue is in commit 7442667 on the dev branch.

A corner case in the handling of _devices[device_id].hit.

While processing the current M-SEARCH request. (_discovering flag is true)
- A past requester, that completed successfully, will request again.
- The past requester's new M-SEARCH is ignored via your _discovering flag.
- However, the requester knows our IP and does a TCP connection and presents a GET /setup.xml HTTP/1.1 request.
- This causes _devices[device_id].hit to be set true, erroneously in _handleSetup(...).
- If that device_id is the same as _current or any other device that has not been serviced, then it will be skipped in _nextUDPResponse().

I made this change in _nextUDPResponse():

    if (_discovering && client->remoteIP == _remoteIP)
        _devices[device_id].hit = true;

I think window for this problem is small; however, it grows as the number of devices grows.

pvint commented 5 years ago

Original comment by Xose Pérez (Bitbucket: [Xose Pérez](https://bitbucket.org/Xose Pérez), ).

This no longer applies