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Blocking calls reported by BlockHound

See original GitHub issue

I’m using Spring WebClient to do a simple GET request to a HTTPS URL. BlockHound reports two blocking calls. 100% standard WebClient & Reactor Netty configuration.

First:

reactor.blockhound.BlockingOperationError: Blocking call! java.io.FileInputStream#readBytes
	at java.base/java.io.FileInputStream.readBytes(FileInputStream.java)
	at java.base/java.io.FileInputStream.read(FileInputStream.java:276)
	at java.base/sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:270)
	at java.base/sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:313)
	at java.base/sun.nio.cs.StreamDecoder.read(StreamDecoder.java:188)
	at java.base/java.io.InputStreamReader.read(InputStreamReader.java:177)
	at java.base/java.io.BufferedReader.fill(BufferedReader.java:162)
	at java.base/java.io.BufferedReader.readLine(BufferedReader.java:329)
	at java.base/java.io.BufferedReader.readLine(BufferedReader.java:396)
	at io.netty.util.NetUtil$1.run(NetUtil.java:167)
	at io.netty.util.NetUtil$1.run(NetUtil.java:151)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:318)
	at io.netty.util.NetUtil.<clinit>(NetUtil.java:151)
	at reactor.netty.transport.AddressUtils.attemptParsingIpString(AddressUtils.java:238)
	at reactor.netty.transport.AddressUtils.createForIpString(AddressUtils.java:259)
	at reactor.netty.transport.AddressUtils.createInetSocketAddress(AddressUtils.java:56)
	at reactor.netty.transport.AddressUtils.createUnresolved(AddressUtils.java:86)
	at reactor.netty.http.client.UriEndpointFactory.lambda$createUriEndpoint$0(UriEndpointFactory.java:64)
	at reactor.netty.http.client.UriEndpoint.toExternalForm(UriEndpoint.java:63)
	at reactor.netty.http.client.HttpClientConnect$HttpClientHandler.<init>(HttpClientConnect.java:493)
	at reactor.netty.http.client.HttpClientConnect$MonoHttpConnect.subscribe(HttpClientConnect.java:207)
	at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64)
	at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52)
	at reactor.core.publisher.Mono.subscribe(Mono.java:4400)
	at reactor.core.publisher.MonoSubscribeOn$SubscribeOnSubscriber.run(MonoSubscribeOn.java:126)
	at reactor.core.scheduler.WorkerTask.call(WorkerTask.java:84)
	at reactor.core.scheduler.WorkerTask.call(WorkerTask.java:37)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:833)

Second:

reactor.blockhound.BlockingOperationError: Blocking call! java.io.FileInputStream#readBytes
	at java.base/java.io.FileInputStream.readBytes(FileInputStream.java)
	at java.base/java.io.FileInputStream.read(FileInputStream.java:276)
	at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:244)
	at java.base/java.io.BufferedInputStream.read(BufferedInputStream.java:263)
	at java.base/sun.security.util.DerValue.<init>(DerValue.java:412)
	at java.base/sun.security.util.DerValue.<init>(DerValue.java:459)
	at java.base/sun.security.pkcs12.PKCS12KeyStore.engineLoad(PKCS12KeyStore.java:2012)
	at java.base/sun.security.util.KeyStoreDelegator.engineLoad(KeyStoreDelegator.java:221)
	at java.base/java.security.KeyStore.load(KeyStore.java:1473)
	at java.base/sun.security.ssl.TrustStoreManager$TrustAnchorManager.loadKeyStore(TrustStoreManager.java:390)
	at java.base/sun.security.ssl.TrustStoreManager$TrustAnchorManager.getTrustedCerts(TrustStoreManager.java:336)
	at java.base/sun.security.ssl.TrustStoreManager.getTrustedCerts(TrustStoreManager.java:57)
	at java.base/sun.security.ssl.TrustManagerFactoryImpl.engineInit(TrustManagerFactoryImpl.java:49)
	at java.base/javax.net.ssl.TrustManagerFactory.init(TrustManagerFactory.java:282)
	at java.base/sun.security.ssl.SSLContextImpl.engineInit(SSLContextImpl.java:94)
	at java.base/javax.net.ssl.SSLContext.init(SSLContext.java:314)
	at io.netty.handler.ssl.JdkSslContext.<clinit>(JdkSslContext.java:75)
	at io.netty.handler.ssl.SslContext.newClientContextInternal(SslContext.java:824)
	at io.netty.handler.ssl.SslContextBuilder.build(SslContextBuilder.java:611)
	at reactor.netty.tcp.AbstractProtocolSslContextSpec.sslContext(AbstractProtocolSslContextSpec.java:53)
	at reactor.netty.tcp.SslProvider.<init>(SslProvider.java:366)
	at reactor.netty.tcp.SslProvider$Build.build(SslProvider.java:742)
	at reactor.netty.http.client.HttpClientSecure.<clinit>(HttpClientSecure.java:59)
	at reactor.netty.http.client.HttpClientConnect$MonoHttpConnect.lambda$subscribe$0(HttpClientConnect.java:219)
	at reactor.core.publisher.MonoCreate.subscribe(MonoCreate.java:57)
	at reactor.core.publisher.FluxRetryWhen.subscribe(FluxRetryWhen.java:77)
	at reactor.core.publisher.MonoRetryWhen.subscribeOrReturn(MonoRetryWhen.java:46)
	at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:57)
	at reactor.netty.http.client.HttpClientConnect$MonoHttpConnect.subscribe(HttpClientConnect.java:271)
	at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64)
	at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52)
	at reactor.core.publisher.Mono.subscribe(Mono.java:4400)
	at reactor.core.publisher.MonoSubscribeOn$SubscribeOnSubscriber.run(MonoSubscribeOn.java:126)
	at reactor.core.scheduler.WorkerTask.call(WorkerTask.java:84)
	at reactor.core.scheduler.WorkerTask.call(WorkerTask.java:37)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:833)

Netty version

4.1.74.Final

JVM version (e.g. `java -version`)

openjdk version “17” 2021-09-14 OpenJDK Runtime Environment (build 17+35-2724) OpenJDK 64-Bit Server VM (build 17+35-2724, mixed mode, sharing)

OS version (e.g. `uname -a`)

Linux * 5.11.0-49-generic #55-Ubuntu SMP Wed Jan 12 17:36:34 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

Issue Analytics

State:
Created 2 years ago
Comments:5 (5 by maintainers)

Top GitHub Comments

1reaction

violetaggcommented, Mar 1, 2022

@micopiira Let’s follow up on Reactor Netty gitter about the SslContext.

1reaction

normanmaurercommented, Feb 28, 2022

@micopiira https://github.com/netty/netty/pull/12130 … The second one actually looks valid as you should not create the SslContext in an event loop thread.

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