24 lines
1.1 KiB
Text
24 lines
1.1 KiB
Text
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> And so we waited. Tick-tock, blink-blink, thirty seconds stretched
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> themselves out one by one, a hole in human experience. -- The Bug
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I *think* I've managed to fully track down the [[webapp_hang]]. It is,
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apparently, a bug in the Warp web server's code intended to protect against
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the [Slowloris](http://ha.ckers.org/slowloris/) attack. It assumes,
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incorrectly, that a web browser won't reuse a connection it's left idle for
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30 seconds. Some bad error handling keeps a connection open with no thread
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to service it, leading to the hang.
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<https://github.com/yesodweb/wai/issues/146>
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Have put a 30 minute timeout into place as a workaround, and, unless
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a web browser sits on an idle connection for a full 30 minutes and then
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tries to reuse it, this should be sufficient.
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I was chasing that bug, quietly, for 6 months. Would see it now and
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then, but not be able to reproduce it or get anywhere with analysis.
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I had nearly given up. If you enjoy stories like that, read Ellen
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Ullman's excellent book The Bug.
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> To discover that between the blinks of the machine’s shuttered eye—going
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> on without pause or cease; simulated, imagined, but still not caught—was
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> life.
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