From 8be77a14ab4e9a63e52c672bdfc3d2e8f9907eca Mon Sep 17 00:00:00 2001
From: Kweku Adams <kwekua@google.com>
Date: Tue, 13 Sep 2022 20:43:32 +0000
Subject: [PATCH] Fix long comparison overflow issue in AlarmQueue.

Bug: 247097209
Test: atest FrameworksMockingServicesTests:AlarmQueueTest
Change-Id: Ib3fd31ca7dc37c18499052d8d4f03814568c11c2
Merged-In: I8e07157fef57f6047414e9c8b46da0dac91c6714
---
 .../com/android/server/utils/AlarmQueue.java  |  6 +++++-
 .../android/server/utils/AlarmQueueTest.java  | 21 +++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/services/core/java/com/android/server/utils/AlarmQueue.java b/services/core/java/com/android/server/utils/AlarmQueue.java
index 3f4def6d60ab7..c9bfc8d74ecd4 100644
--- a/services/core/java/com/android/server/utils/AlarmQueue.java
+++ b/services/core/java/com/android/server/utils/AlarmQueue.java
@@ -34,6 +34,7 @@ import android.util.Slog;
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
 
+import java.util.Comparator;
 import java.util.PriorityQueue;
 import java.util.function.Predicate;
 
@@ -58,8 +59,11 @@ public abstract class AlarmQueue<K> implements AlarmManager.OnAlarmListener {
      * The pair is the key and its associated alarm time (in the elapsed realtime timebase).
      */
     private static class AlarmPriorityQueue<Q> extends PriorityQueue<Pair<Q, Long>> {
+        private static final Comparator<Pair<?, Long>> sTimeComparator =
+                (o1, o2) -> Long.compare(o1.second, o2.second);
+
         AlarmPriorityQueue() {
-            super(1, (o1, o2) -> (int) (o1.second - o2.second));
+            super(1, sTimeComparator);
         }
 
         /**
diff --git a/services/tests/mockingservicestests/src/com/android/server/utils/AlarmQueueTest.java b/services/tests/mockingservicestests/src/com/android/server/utils/AlarmQueueTest.java
index 849e6730ac116..00d7541a79dcf 100644
--- a/services/tests/mockingservicestests/src/com/android/server/utils/AlarmQueueTest.java
+++ b/services/tests/mockingservicestests/src/com/android/server/utils/AlarmQueueTest.java
@@ -155,6 +155,27 @@ public class AlarmQueueTest {
                 anyInt(), eq(nowElapsed + HOUR_IN_MILLIS), eq(ALARM_TAG), any(), any());
     }
 
+    @Test
+    public void testAddingLargeAlarmTimes() {
+        final AlarmQueue<String> alarmQueue = createAlarmQueue(true, 0);
+        final long nowElapsed = mInjector.getElapsedRealtime();
+
+        InOrder inOrder = inOrder(mAlarmManager);
+
+        alarmQueue.addAlarm("com.android.test.1", Long.MAX_VALUE - 5);
+        inOrder.verify(mAlarmManager, timeout(1000).times(1))
+                .setExact(anyInt(), eq(Long.MAX_VALUE - 5), eq(ALARM_TAG), any(), any());
+        alarmQueue.addAlarm("com.android.test.2", Long.MAX_VALUE - 4);
+        inOrder.verify(mAlarmManager, never())
+                .setExact(anyInt(), anyLong(), eq(ALARM_TAG), any(), any());
+        alarmQueue.addAlarm("com.android.test.3", nowElapsed + 5);
+        inOrder.verify(mAlarmManager, timeout(1000).times(1))
+                .setExact(anyInt(), eq(nowElapsed + 5), eq(ALARM_TAG), any(), any());
+        alarmQueue.addAlarm("com.android.test.4", nowElapsed + 6);
+        inOrder.verify(mAlarmManager, never())
+                .setExact(anyInt(), anyLong(), eq(ALARM_TAG), any(), any());
+    }
+
     /**
      * Verify that updating the alarm time for a key will result in the AlarmManager alarm changing,
      * if needed.