Flooding requests results in memory leak #43548
Description
Version
v16.15.1
Platform
Linux DNSBox 5.15.0-39-generic #42-Ubuntu SMP Thu Jun 9 23:42:32 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Subsystem
HTTP
What steps will reproduce the bug?
1. Run the code below using node without requiring any additional dependencies
const fs = require('fs');
const http = require('http');
const app = (req, res) => {
res.end(JSON.stringify({
message: 'Hello World!'
}));
};
const httpServer = http.createServer(app);
httpServer.listen(80, () => {
console.log('HTTP Server running on port 80');
});2. Use this site to stress-test the server using the following configuration below.
Type: Layer 7
Target URL: ...
Duration (Seconds): 300
Network (Power): Basic (1 Thread)
Request Type: GET
Attack Method: HTTP/s (SPAM)
How often does it reproduce? Is there a required condition?
You might have to run the test twice for it to take effect but you have to wait for the current test to finish before sending another one. After all of the tests are complete, the server will get a lot of MaxListenersExceededWarning errors and will eventually crash because it will reach the memory limit.
What is the expected behavior?
It shouldn't show a memory leak error and should just continue the requests as normal.
What do you see instead?
(node:16418) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 error listeners added to [TLSSocket]. Use emitter.setMaxListeners() to increase limit
at _addListener (node:events:601:17)
at TLSSocket.addListener (node:events:619:10)
at TLSSocket.Readable.on (node:internal/streams/readable:875:35)
at TLSSocket.socketListenerWrap [as on] (node:_http_server:1007:54)
at TLSSocket.socketOnError (node:_http_server:672:8)
at onParserExecuteCommon (node:_http_server:702:19)
at onParserExecute (node:_http_server:646:3)
Additional information
What I have debugged so far in Node.js is that the case seems to be a flaw in the logic of that internal
socketOnErrorfunction. When it is called, it removes itself from the list of error listeners and then adds a new error listener,noop. It seems that at some point, that listener was the only waysocketOnErrorwas invoked. But you will find in their code there are now multiple places in whichsocketOnErroris invoked, and removing that error listener doesn't stop them all. Additional invokations for the same socket keep adding thatnooplistener, and the state at which the warning happens, there are 10nooplisteners on the socket, and the warning happens when the 11thnooplistener is added.