NullPointerException on commonCompleteSegmentByteCount

[vitorpamplona]

Looks like there is a possible NPE in commonCompleteSegmentByteCount.

I can't reproduce this bug but this is a PlayStore stack from an Xperia 5 II running Android 12 (SDK 31)

Exception java.lang.NullPointerException:
  at okio.internal.-Buffer.commonCompleteSegmentByteCount (-Buffer.java)
  at okio.Buffer.completeSegmentByteCount (Buffer.kt)
  at okio.RealBufferedSink.emitCompleteSegments (RealBufferedSink.kt)
  at okio.DeflaterSink.deflate (DeflaterSink.kt)
  at okio.DeflaterSink.finishDeflate$okio (DeflaterSink.kt)
  at okio.DeflaterSink.close (DeflaterSink.kt)
  at okhttp3.internal.ws.MessageDeflater.close (MessageDeflater.kt)
  at okhttp3.internal.ws.WebSocketWriter.close (WebSocketWriter.kt)
  at okhttp3.internal._UtilCommonKt.closeQuietly (-UtilCommon.kt)
  at okhttp3.internal.ws.RealWebSocket.failWebSocket (RealWebSocket.kt)
  at okhttp3.internal.ws.RealWebSocket$connect$1.onResponse (RealWebSocket.kt)
  at okhttp3.internal.connection.RealCall$AsyncCall.run (RealCall.kt)
  at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1145)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:644)
  at java.lang.Thread.run (Thread.java:1012)

The code is using versions:

• com.squareup.okhttp3:okhttp:5.0.0-alpha.11
• com.squareup.okio:okio-jvm:3.6.0
• com.squareup.okio:okio:3.6.0

[swankjesse]

@vitorpamplona is it possible you’re operating on your Okio streams from multiple threads concurrently? Concurrent modifications can trigger errors like this.

[swankjesse]

Oooh, actually it’s OkHttp to blame for exactly that, and that bug is very recently fixed.
square/okhttp#8121

Will ship a new OkHttp 5.0 alpha very soon with that fix.

[vitorpamplona]

I don't use okio streams directly. I just used them through OkHttp. I assume OkHttp takes care of the thread handling part.

Do I need to take additional protections when multithreading?

[vitorpamplona]

Thank you! ☺️