From 13c7b270e22ff628a3555d59fce21b1595ff4615 Mon Sep 17 00:00:00 2001
From: Curtis Belmonte <curtislb@google.com>
Date: Mon, 15 Mar 2021 14:04:08 -0700
Subject: [PATCH] Fix possible NPE in fingerprint service provider

Test: atest FingerprintManagerTest

Bug: 179073068
Change-Id: If624d54834c443b727e574333a4bd116f11a297c
---
 .../sensors/fingerprint/ServiceProvider.java        |  8 +++++++-
 .../fingerprint/aidl/FingerprintProvider.java       | 13 +++++++++++--
 .../sensors/fingerprint/hidl/Fingerprint21.java     |  2 +-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/services/core/java/com/android/server/biometrics/sensors/fingerprint/ServiceProvider.java b/services/core/java/com/android/server/biometrics/sensors/fingerprint/ServiceProvider.java
index dfec2e3e308f7..0d50499bd02a1 100644
--- a/services/core/java/com/android/server/biometrics/sensors/fingerprint/ServiceProvider.java
+++ b/services/core/java/com/android/server/biometrics/sensors/fingerprint/ServiceProvider.java
@@ -67,7 +67,13 @@ public interface ServiceProvider {
     @NonNull
     List<FingerprintSensorPropertiesInternal> getSensorProperties();
 
-    @NonNull
+    /**
+     * Returns the internal properties of the specified sensor, if owned by this provider.
+     *
+     * @param sensorId The ID of a fingerprint sensor, or -1 for any sensor.
+     * @return An object representing the internal properties of the specified sensor.
+     */
+    @Nullable
     FingerprintSensorPropertiesInternal getSensorProperties(int sensorId);
 
     void scheduleResetLockout(int sensorId, int userId, @Nullable byte[] hardwareAuthToken);
diff --git a/services/core/java/com/android/server/biometrics/sensors/fingerprint/aidl/FingerprintProvider.java b/services/core/java/com/android/server/biometrics/sensors/fingerprint/aidl/FingerprintProvider.java
index 598cc8992c2db..d798198782eae 100644
--- a/services/core/java/com/android/server/biometrics/sensors/fingerprint/aidl/FingerprintProvider.java
+++ b/services/core/java/com/android/server/biometrics/sensors/fingerprint/aidl/FingerprintProvider.java
@@ -16,6 +16,8 @@
 
 package com.android.server.biometrics.sensors.fingerprint.aidl;
 
+import static android.hardware.fingerprint.FingerprintManager.SENSOR_ID_ANY;
+
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.ActivityManager;
@@ -240,10 +242,17 @@ public class FingerprintProvider implements IBinder.DeathRecipient, ServiceProvi
         return props;
     }
 
-    @NonNull
+    @Nullable
     @Override
     public FingerprintSensorPropertiesInternal getSensorProperties(int sensorId) {
-        return mSensors.get(sensorId).getSensorProperties();
+        if (mSensors.size() == 0) {
+            return null;
+        } else if (sensorId == SENSOR_ID_ANY) {
+            return mSensors.valueAt(0).getSensorProperties();
+        } else {
+            final Sensor sensor = mSensors.get(sensorId);
+            return sensor != null ? sensor.getSensorProperties() : null;
+        }
     }
 
     private void scheduleLoadAuthenticatorIds(int sensorId) {
diff --git a/services/core/java/com/android/server/biometrics/sensors/fingerprint/hidl/Fingerprint21.java b/services/core/java/com/android/server/biometrics/sensors/fingerprint/hidl/Fingerprint21.java
index 6e22a797b435b..fd3db6072357e 100644
--- a/services/core/java/com/android/server/biometrics/sensors/fingerprint/hidl/Fingerprint21.java
+++ b/services/core/java/com/android/server/biometrics/sensors/fingerprint/hidl/Fingerprint21.java
@@ -515,7 +515,7 @@ public class Fingerprint21 implements IHwBinder.DeathRecipient, ServiceProvider
         return properties;
     }
 
-    @NonNull
+    @Nullable
     @Override
     public FingerprintSensorPropertiesInternal getSensorProperties(int sensorId) {
         return mSensorProperties;