ANR caused by main-thread work in onMalwareDetected (reflection + PackageManager calls) #214

:::writing{variant=“standard” id=“92741”}
Title: ANR caused by main-thread work in onMalwareDetected (reflection + PackageManager calls)

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Description

We encountered ANR issues caused by heavy work being executed on the main thread inside onMalwareDetected.

From the stack trace, the callback triggers:
• Reflection (Class.getMethod)
• OEM framework hooks (TranReflectHelper)
• PackageManager calls (getApplicationLabel)
• Resource loading

All of these are happening on the UI thread, leading to freezes and ANR.

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Stack Trace (key part)

at java.lang.Class.getMethod
at com.transsion.hubcore.proxy.TranReflectHelper.getMethod
at android.app.ApplicationPackageManager.getApplicationLabel
at com.aheaditec.freerasp.ExtensionsKt.toPigeon
at com.aheaditec.freerasp.handlers.MethodCallHandler$sink$1.onMalwareDetected

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Root Cause

Inside onMalwareDetected, this line performs heavy work on the main thread:

val pigeonPackageInfo = packageInfo.map { it.toPigeon(context) }

toPigeon(context) internally calls:
• PackageManager
• resource loading
• label resolution

This blocks the main thread.

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Original Code

override fun onMalwareDetected(packageInfo: List) {
context?.let { context ->
val pigeonPackageInfo = packageInfo.map { it.toPigeon(context) }
talsecPigeon?.onMalwareDetected(pigeonPackageInfo) { result ->
result.getOrElse {
Log.e("MethodCallHandlerSink", "Result ended with failure")
throw it
}
}
}
}

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Proposed Fix

Move heavy processing off the main thread:

override fun onMalwareDetected(packageInfo: List) {
val ctx = context ?: return
backgroundHandler.post {
val pigeonPackageInfo = packageInfo.map { it.toPigeon(ctx) }
mainHandler.post {
talsecPigeon?.onMalwareDetected(pigeonPackageInfo) { result ->
result.getOrElse {
Log.e("MethodCallHandlerSink", "Result ended with failure")
throw it
}
}
}
}
}

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Expected Behavior
• No heavy work should run on the main thread
• Detection callbacks should be non-blocking

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Impact
• UI freeze
• ANR on certain devices (especially Transsion / OEM-modified systems)

⸻

Please consider moving heavy operations (like toPigeon) off the main thread internally or documenting this requirement clearly.

Thanks.