Verify arguments passed are non-null.

We should verify they are non-null before
handing them off to other threads to avoid
crashing the system_server process.

Bug: 356731520
Test: atest services/tests/powerstatstests/src/com/android/server/powerstats/PowerStatsServiceTest.java
Flag: com.android.server.powerstats.verify_non_null_arguments
Change-Id: I5b0cbf86976e74fd01e3d70ac01a03398ecdaa56
diff --git a/services/core/java/com/android/server/powerstats/PowerStatsService.java b/services/core/java/com/android/server/powerstats/PowerStatsService.java
index 8f99d28..1ca267e99 100644
--- a/services/core/java/com/android/server/powerstats/PowerStatsService.java
+++ b/services/core/java/com/android/server/powerstats/PowerStatsService.java
@@ -62,6 +62,7 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
 
@@ -207,19 +208,28 @@
     private final IBinder mService = new IPowerStatsService.Stub() {
 
         @Override
-        public void getSupportedPowerMonitors(ResultReceiver resultReceiver) {
+        public void getSupportedPowerMonitors(@NonNull ResultReceiver resultReceiver) {
+            if (Flags.verifyNonNullArguments()) {
+                Objects.requireNonNull(resultReceiver);
+            }
             getHandler().post(() -> getSupportedPowerMonitorsImpl(resultReceiver));
         }
 
         @Override
-        public void getPowerMonitorReadings(int[] powerMonitorIds, ResultReceiver resultReceiver) {
+        public void getPowerMonitorReadings(@NonNull int[] powerMonitorIds,
+                @NonNull ResultReceiver resultReceiver) {
+            if (Flags.verifyNonNullArguments()) {
+                Objects.requireNonNull(powerMonitorIds);
+                Objects.requireNonNull(resultReceiver);
+            }
             int callingUid = Binder.getCallingUid();
             getHandler().post(() ->
                     getPowerMonitorReadingsImpl(powerMonitorIds, resultReceiver, callingUid));
         }
 
         @Override
-        protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+        protected void dump(@NonNull FileDescriptor fd, @NonNull PrintWriter pw,
+                @Nullable String[] args) {
             if (!DumpUtils.checkDumpPermission(mContext, TAG, pw)) return;
 
             if (mPowerStatsLogger == null) {
@@ -263,6 +273,11 @@
         }
     };
 
+    @VisibleForTesting
+    IPowerStatsService getIPowerStatsServiceForTest() {
+        return (IPowerStatsService) mService;
+    }
+
     private class DeviceConfigListener implements DeviceConfig.OnPropertiesChangedListener {
         public Executor mExecutor = new HandlerExecutor(getHandler());
 
diff --git a/services/core/java/com/android/server/powerstats/flags.aconfig b/services/core/java/com/android/server/powerstats/flags.aconfig
index 0a4a751..29ad7dc 100644
--- a/services/core/java/com/android/server/powerstats/flags.aconfig
+++ b/services/core/java/com/android/server/powerstats/flags.aconfig
@@ -10,4 +10,15 @@
     metadata {
         purpose: PURPOSE_BUGFIX
     }
+}
+
+flag {
+    name: "verify_non_null_arguments"
+    namespace: "backstage_power"
+    description: "Verify arguments passed are non-null"
+    bug: "356731520"
+    is_fixed_read_only: true
+    metadata {
+        purpose: PURPOSE_BUGFIX
+    }
 }
\ No newline at end of file
diff --git a/services/tests/powerstatstests/src/com/android/server/powerstats/PowerStatsServiceTest.java b/services/tests/powerstatstests/src/com/android/server/powerstats/PowerStatsServiceTest.java
index 1838fe8..53e3143 100644
--- a/services/tests/powerstatstests/src/com/android/server/powerstats/PowerStatsServiceTest.java
+++ b/services/tests/powerstatstests/src/com/android/server/powerstats/PowerStatsServiceTest.java
@@ -19,6 +19,7 @@
 import static com.google.common.truth.Truth.assertThat;
 
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -37,6 +38,8 @@
 import android.os.Looper;
 import android.os.PowerMonitor;
 import android.os.ResultReceiver;
+import android.platform.test.annotations.EnableFlags;
+import android.platform.test.flag.junit.SetFlagsRule;
 import android.provider.DeviceConfig;
 import android.provider.DeviceConfigInterface;
 
@@ -58,6 +61,7 @@
 import com.android.server.testutils.FakeDeviceConfigInterface;
 
 import org.junit.Before;
+import org.junit.Rule;
 import org.junit.Test;
 
 import java.io.ByteArrayOutputStream;
@@ -101,6 +105,8 @@
     private static final int STATE_RESIDENCY_COUNT = 4;
     private static final int APP_UID = 10042;
 
+    @Rule public final SetFlagsRule mSetFlagsRule = new SetFlagsRule();
+
     private final Context mContext = InstrumentationRegistry.getInstrumentation().getContext();
     private PowerStatsService mService;
     private TestPowerStatsHALWrapper mPowerStatsHALWrapper = new TestPowerStatsHALWrapper();
@@ -1198,4 +1204,22 @@
         assertThat(Arrays.stream(supportedPowerMonitorsResult.powerMonitors)
                 .map(PowerMonitor::getName).toList()).contains("ENERGYCONSUMER0");
     }
+
+    @EnableFlags(Flags.FLAG_VERIFY_NON_NULL_ARGUMENTS)
+    @Test
+    public void testGetSupportedPowerMonitors_withNullArguments() {
+        IPowerStatsService iPowerStatsService = mService.getIPowerStatsServiceForTest();
+        assertThrows(NullPointerException.class,
+                () -> iPowerStatsService.getSupportedPowerMonitors(null));
+    }
+
+    @EnableFlags(Flags.FLAG_VERIFY_NON_NULL_ARGUMENTS)
+    @Test
+    public void testGetPowerMonitorReadings_withNullArguments() {
+        IPowerStatsService iPowerStatsService = mService.getIPowerStatsServiceForTest();
+        assertThrows(NullPointerException.class, () -> iPowerStatsService.getPowerMonitorReadings(
+                null, new GetPowerMonitorsResult()));
+        assertThrows(NullPointerException.class, () -> iPowerStatsService.getPowerMonitorReadings(
+                new int[] {0}, null));
+    }
 }