fix(root): add a process timeout to RootDetector

Author: lemnik

CHANGELOG.md

@@ -6,6 +6,8 @@
 
 * The `bugsnag-plugin-android-exitinfo` plugin now calls `setProcessState` (if configured) on a background thread and swallows any rate-limiting errors, so that it does not block the main thread during startup
   [#2197](https://github.com/bugsnag/bugsnag-android/pull/2197)
+* Fixed a background ANR that could occur during startup if processes do not launch or run quickly enough
+  [#2201](https://github.com/bugsnag/bugsnag-android/pull/2201)
 
 ## 6.14.0 (2025-06-04)
 

bugsnag-android-core/detekt-baseline.xml

@@ -61,6 +61,7 @@
     <ID>SwallowedException:ForegroundDetector.kt$ForegroundDetector$e: Exception</ID>
     <ID>SwallowedException:JsonHelperTest.kt$JsonHelperTest$e: IllegalArgumentException</ID>
     <ID>SwallowedException:PluginClient.kt$PluginClient$exc: ClassNotFoundException</ID>
+    <ID>SwallowedException:RootDetector.kt$RootDetector$ex: IllegalThreadStateException</ID>
     <ID>SwallowedException:SharedPrefMigrator.kt$SharedPrefMigrator$e: RuntimeException</ID>
     <ID>ThrowsCount:JsonHelper.kt$JsonHelper$fun jsonToLong(value: Any?): Long?</ID>
     <ID>TooManyFunctions:ConfigInternal.kt$ConfigInternal : CallbackAwareMetadataAwareUserAwareFeatureFlagAware</ID>

bugsnag-android-core/src/main/java/com/bugsnag/android/RootDetector.kt

@@ -1,9 +1,14 @@
 package com.bugsnag.android
 
+import android.os.Build
+import android.os.SystemClock
 import androidx.annotation.VisibleForTesting
 import java.io.File
 import java.io.IOException
 import java.io.Reader
+import java.lang.Thread
+import java.util.concurrent.TimeUnit
+import kotlin.math.min
 
 /**
  * Attempts to detect whether the device is rooted. Root detection errs on the side of false
@@ -21,6 +26,9 @@ internal class RootDetector @JvmOverloads constructor(
 ) {
 
     companion object {
+        private const val PROCESS_TIMEOUT = 250L
+        private const val PROCESS_POLL_DELAY = 50L
+
         private val BUILD_PROP_FILE = File("/system/build.prop")
 
         private val ROOT_INDICATORS = listOf(
@@ -120,7 +128,20 @@ internal class RootDetector @JvmOverloads constructor(
         var process: Process? = null
         return try {
             process = processBuilder.start()
+            val processComplete = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+                process.waitFor(PROCESS_TIMEOUT, TimeUnit.MILLISECONDS)
+            } else {
+                process.fallbackWaitFor(PROCESS_TIMEOUT)
+            }
+
+            if (!processComplete) {
+                return false
+            }
+
             process.inputStream.bufferedReader().use { it.isNotBlank() }
+        } catch (ignored: InterruptedException) {
+            Thread.currentThread().interrupt() // restore the interrupted status
+            false
         } catch (ignored: IOException) {
             false
         } finally {
@@ -147,4 +168,19 @@ internal class RootDetector @JvmOverloads constructor(
         libraryLoaded -> performNativeRootChecks()
         else -> false
     }
+
+    private fun Process.fallbackWaitFor(timeout: Long): Boolean {
+        val endTime = SystemClock.elapsedRealtime() + timeout
+        while (SystemClock.elapsedRealtime() < endTime) {
+            try {
+                exitValue()
+                return true
+            } catch (ex: IllegalThreadStateException) {
+                // Process is still running, wait a bit before checking again
+                Thread.sleep(min(PROCESS_POLL_DELAY, endTime - SystemClock.elapsedRealtime()))
+            }
+        }
+
+        return false
+    }
 }