EAP 7 Undertow AjpReadListener throws StackOverflowError

Solution Unverified - Updated 13 Jun 2024

Environment

JBoss Enterprise Application Platform (EAP)
- 7.3.5+

Issue

We see a StackOverflowError from repeating AjpReadListener calls like below:

ERROR [org.xnio.listener] (default I/O-17) XNIO001007: A channel event listener threw an exception: java.lang.StackOverflowError
	at org.jboss.logmanager.formatters.Formatters$7.renderRaw(Formatters.java:450)
	at org.jboss.logmanager.formatters.Formatters$JustifyingFormatStep.render(Formatters.java:215)
	at org.jboss.logmanager.formatters.MultistepFormatter.format(MultistepFormatter.java:89)
	at org.jboss.logmanager.ExtFormatter.format(ExtFormatter.java:32)
	at org.jboss.logmanager.handlers.WriterHandler.doPublish(WriterHandler.java:46)
	at org.jboss.logmanager.ExtHandler.publish(ExtHandler.java:77)
	at org.jboss.logmanager.LoggerNode.publish(LoggerNode.java:333)
	at org.jboss.logmanager.LoggerNode.publish(LoggerNode.java:341)
	at org.jboss.logmanager.LoggerNode.publish(LoggerNode.java:341)
	at org.jboss.logmanager.LoggerNode.publish(LoggerNode.java:341)
	at org.jboss.logmanager.Logger.logRaw(Logger.java:852)
	at org.jboss.logmanager.Logger.log(Logger.java:804)
	at org.jboss.logging.JBossLogManagerLogger.doLogf(JBossLogManagerLogger.java:53)
	at org.jboss.logging.Logger.logf(Logger.java:2445)
	at io.undertow.UndertowLogger_$logger.exceptionProcessingRequest(UndertowLogger_$logger.java:57)
	at io.undertow.server.protocol.ajp.AjpReadListener.handleEvent(AjpReadListener.java:252)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.sendMessages(AjpReadListener.java:316)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.handleInternalServerError(AjpReadListener.java:261)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.handleEvent(AjpReadListener.java:249)
...
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.sendMessages(AjpReadListener.java:316)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.handleInternalServerError(AjpReadListener.java:261)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.handleEvent(AjpReadListener.java:249)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.server.protocol.ajp.AjpReadListener.handleEvent(AjpReadListener.java:56)
	at org.jboss.xnio@3.8.4.Final-redhat-00001//org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92)
	at org.jboss.xnio@3.8.4.Final-redhat-00001//org.xnio.conduits.ReadReadyHandler$ChannelListenerHandler.readReady(ReadReadyHandler.java:66)
	at io.undertow.core@2.2.9.SP1-redhat-00001//io.undertow.conduits.ReadTimeoutStreamSourceConduit$2.readReady(ReadTimeoutStreamSourceConduit.java:99)
	at org.jboss.xnio.nio@3.8.4.Final-redhat-00001//org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89)
	at org.jboss.xnio.nio@3.8.4.Final-redhat-00001//org.xnio.nio.NioHandle$1.run(NioHandle.java:50)
	at org.jboss.xnio.nio@3.8.4.Final-redhat-00001//org.xnio.nio.WorkerThread.safeRun(WorkerThread.java:612)
	at org.jboss.xnio.nio@3.8.4.Final-redhat-00001//org.xnio.nio.WorkerThread.run(WorkerThread.java:479)

Resolution

Await a fix in a later EAP patch (7.4.4+)
Remove any read-timeout from AJP listeners as a workaround or ignore the exception in the meantime as it otherwise has no functional impact on the already timed out connection.

Root Cause

This content is not included.UNDERTOW-2002
This content is not included.JBEAP-22861
Handling of a ReadTimeoutException is recursively failing with repeating ReadTimeoutExceptions. This may be seen in the event of a timeout reached and induced by any configured read-timeout on an ajp-listener:

                <ajp-listener name="ajp" socket-binding="ajp" read-timeout="#" write-timeout="#" />

Diagnostic Steps

Capture DEBUG logs for io.undertow from the issue and check that ReadTimeoutExceptions are occurring like below:

DEBUG [io.undertow.request.io] (default I/O-14) UT005013: An IOException occurred: org.xnio.channels.ReadTimeoutException: UT000199: Read timed out after 1638571000771 milliseconds.
	at io.undertow.conduits.ReadTimeoutStreamSourceConduit.checkExpired(ReadTimeoutStreamSourceConduit.java:238)
	at io.undertow.conduits.ReadTimeoutStreamSourceConduit.read(ReadTimeoutStreamSourceConduit.java:169)
	at org.xnio.conduits.ConduitStreamSourceChannel.read(ConduitStreamSourceChannel.java:127)
	at io.undertow.server.protocol.ajp.AjpReadListener.handleEvent(AjpReadListener.java:125)
	at io.undertow.server.protocol.ajp.AjpReadListener.sendMessages(AjpReadListener.java:316)
	at io.undertow.server.protocol.ajp.AjpReadListener.handleInternalServerError(AjpReadListener.java:261)

SBR

Webservers

Product(s)

Red Hat JBoss Enterprise Application Platform

Components

jbossas

Category

Troubleshoot

Tags

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