[Android] OnCommissioningComplete handling in AndroidDeviceControllerWrapper.cpp occasionally crashes

[g-coppock]

Problem

When commissioning on Android, an issue is occasionally seen when OnCommissioningComplete is invoked. The general steps are:

1. BLE Connect (m5stack in this case)
2. EstablishPASEConnection
3. Commission (using Wi-Fi credentials)

After receiving the response to the CommissioningComplete command, a crash is seen:

2022-01-13 16:54:45.459 10789-10904 D/DMG: Received Command Response Data, Endpoint=0 Cluster=0x0000_0030 Command=0x0000_0005
2022-01-13 16:54:45.459 10789-10904 D/ZCL: CommissioningCompleteResponse:
2022-01-13 16:54:45.459 10789-10904 D/ZCL:   errorCode: 0
2022-01-13 16:54:45.459 10789-10904 D/ZCL:   debugText: 
2022-01-13 16:54:45.459 10789-10904 D/CTL: Received success response 0x0
2022-01-13 16:54:45.459 10789-10904 D/CTL: Rendezvous cleanup
2022-01-13 16:54:45.461 10789-10904 V/ChipController: onCommissioningComplete(32A2BD0AEE5E34F7, 0) [CONTEXT forced=true service_id=288 ]
2022-01-13 16:54:45.462 10789-10904 A/java_vm_ext.cc:579] JNI DETECTED ERROR IN APPLICATION: jarray argument has non-array type: java.lang.Class<dalvik.annotation.optimization.CriticalNative>
    java_vm_ext.cc:579]     in call to ReleaseByteArrayElements

When debugging, the line on which the crash is occurring is:

https://github.com/project-chip/connectedhomeip/blob/master/src/controller/java/AndroidDeviceControllerWrapper.cpp#L395

if (operationalDatasetBytes != nullptr)
{
    env->ReleaseByteArrayElements(operationalDatasetBytes, operationalDataset, 0); // This line
    env->DeleteGlobalRef(operationalDatasetBytes);
}

It seems to indicate that operationalDatasetBytes is non-null. However, this is on the Wi-Fi commissioning path, and via logging I've verified that the line which assigns operationalDatasetBytes is never reached.

[mspang]

diff --git a/src/controller/java/AndroidDeviceControllerWrapper.h b/src/controller/java/AndroidDeviceControllerWrapper.h
index 02c26e1a1..a556ce550 100644
--- a/src/controller/java/AndroidDeviceControllerWrapper.h
+++ b/src/controller/java/AndroidDeviceControllerWrapper.h
@@ -120,12 +120,12 @@ private:
     bool mNodeIdRequested             = false;
 
     // These fields allow us to release the string/byte array memory later.
-    jstring ssidStr;
-    jstring passwordStr;
-    const char * ssid;
-    const char * password;
-    jbyteArray operationalDatasetBytes;
-    jbyte * operationalDataset;
+    jstring ssidStr = nullptr;
+    jstring passwordStr = nullptr;
+    const char * ssid = nullptr;
+    const char * password = nullptr;
+    jbyteArray operationalDatasetBytes = nullptr;
+    jbyte * operationalDataset = nullptr;
 
     AndroidDeviceControllerWrapper(ChipDeviceControllerPtr controller) : mController(std::move(controller))
     {

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