From b5345b5c30be5ff0ce3a65c7af334419f63fa778 Mon Sep 17 00:00:00 2001
From: JW Wang <wangchun@google.com>
Date: Fri, 26 Nov 2021 15:53:07 +0800
Subject: [PATCH] Fix NPE caused by orphaned child sessions

A null session will cause NPE in mSessionCreationComparator.

Bug: 207814360
Test: adb shell dumpsys package
Change-Id: I15f2848bc40edab2ef09f44a28b2df9e9ad27e78
---
 .../server/pm/PackageInstallerService.java        | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/services/core/java/com/android/server/pm/PackageInstallerService.java b/services/core/java/com/android/server/pm/PackageInstallerService.java
index 7c8515b5e33e4..4767d3a4c0650 100644
--- a/services/core/java/com/android/server/pm/PackageInstallerService.java
+++ b/services/core/java/com/android/server/pm/PackageInstallerService.java
@@ -1461,8 +1461,9 @@ public class PackageInstallerService extends IPackageInstaller.Stub implements
         private TreeMap<PackageInstallerSession, TreeSet<PackageInstallerSession>> mSessionMap;
 
         private final Comparator<PackageInstallerSession> mSessionCreationComparator =
-                Comparator.comparingLong((PackageInstallerSession sess) -> sess.createdMillis)
-                          .thenComparingInt(sess -> sess.sessionId);
+                Comparator.comparingLong(
+                        (PackageInstallerSession sess) -> sess != null ? sess.createdMillis : -1)
+                        .thenComparingInt(sess -> sess != null ? sess.sessionId : -1);
 
         ParentChildSessionMap() {
             mSessionMap = new TreeMap<>(mSessionCreationComparator);
@@ -1500,10 +1501,12 @@ public class PackageInstallerService extends IPackageInstaller.Stub implements
             for (Map.Entry<PackageInstallerSession, TreeSet<PackageInstallerSession>> entry
                     : mSessionMap.entrySet()) {
                 PackageInstallerSession parentSession = entry.getKey();
-                pw.print(tag + " ");
-                parentSession.dump(pw);
-                pw.println();
-                pw.increaseIndent();
+                if (parentSession != null) {
+                    pw.print(tag + " ");
+                    parentSession.dump(pw);
+                    pw.println();
+                    pw.increaseIndent();
+                }
 
                 for (PackageInstallerSession childSession : entry.getValue()) {
                     pw.print(tag + " Child ");