From f7ee7642bccb7b112dbe34d56e417f0253753eb5 Mon Sep 17 00:00:00 2001
From: William Loh <wloh@google.com>
Date: Wed, 1 Feb 2023 22:21:41 +0000
Subject: [PATCH] Remove app metadata if data is null or empty

The getAppMetadata API will now remove any metadata that may have
already been set in the same install session if the data param is set to
null or a empty bundle.

Bug: 265896861
Test: atest android.packageinstaller.install.cts.InstallAppMetadataTest
Change-Id: I95c611c71f978629ca1e7781e3515e2a67cceba6
---
 .../content/pm/IPackageInstallerSession.aidl       |  1 +
 core/java/android/content/pm/PackageInstaller.java | 14 ++++++++++----
 .../android/server/pm/PackageInstallerSession.java | 13 ++++++++++++-
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/core/java/android/content/pm/IPackageInstallerSession.aidl b/core/java/android/content/pm/IPackageInstallerSession.aidl
index 9c1318ee52da0..081f263b698e7 100644
--- a/core/java/android/content/pm/IPackageInstallerSession.aidl
+++ b/core/java/android/content/pm/IPackageInstallerSession.aidl
@@ -69,4 +69,5 @@ interface IPackageInstallerSession {
 
     ParcelFileDescriptor getAppMetadataFd();
     ParcelFileDescriptor openWriteAppMetadata();
+    void removeAppMetadata();
 }
diff --git a/core/java/android/content/pm/PackageInstaller.java b/core/java/android/content/pm/PackageInstaller.java
index d1f28ee42ed4f..f752c166fd69c 100644
--- a/core/java/android/content/pm/PackageInstaller.java
+++ b/core/java/android/content/pm/PackageInstaller.java
@@ -1956,16 +1956,22 @@ public class PackageInstaller {
         /**
          * Optionally set the app metadata. The size of this data cannot exceed the maximum allowed.
          * Any existing data from the previous install will not be retained even if no data is set
-         * for the current install session.
+         * for the current install session. Setting data to null or an empty PersistableBundle will
+         * remove any metadata that has previously been set in the same session.
          *
-         * @param data a PersistableBundle containing the app metadata. If this is set to null then
-         *     any existing app metadata will be removed.
+         * @param data a PersistableBundle containing the app metadata.
          * @throws IOException if writing the data fails.
          */
         public void setAppMetadata(@Nullable PersistableBundle data) throws IOException {
-            if (data == null) {
+            if (data == null || data.isEmpty()) {
+                try {
+                    mSession.removeAppMetadata();
+                } catch (RemoteException e) {
+                    throw e.rethrowFromSystemServer();
+                }
                 return;
             }
+            Objects.requireNonNull(data);
             try (OutputStream outputStream = openWriteAppMetadata()) {
                 data.writeToStream(outputStream);
             }
diff --git a/services/core/java/com/android/server/pm/PackageInstallerSession.java b/services/core/java/com/android/server/pm/PackageInstallerSession.java
index 47e18f1df774d..7a9d8ac4c235a 100644
--- a/services/core/java/com/android/server/pm/PackageInstallerSession.java
+++ b/services/core/java/com/android/server/pm/PackageInstallerSession.java
@@ -1520,7 +1520,10 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
     public ParcelFileDescriptor getAppMetadataFd() {
         assertCallerIsOwnerOrRoot();
         synchronized (mLock) {
-            assertPreparedAndNotCommittedOrDestroyedLocked("openRead");
+            assertPreparedAndNotCommittedOrDestroyedLocked("getAppMetadataFd");
+            if (getStagedAppMetadataFile() == null) {
+                return null;
+            }
             try {
                 return openReadInternalLocked(APP_METADATA_FILE_NAME);
             } catch (IOException e) {
@@ -1529,6 +1532,14 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
         }
     }
 
+    @Override
+    public void removeAppMetadata() {
+        File file = getStagedAppMetadataFile();
+        if (file != null) {
+            file.delete();
+        }
+    }
+
     private static long getAppMetadataSizeLimit() {
         final long token = Binder.clearCallingIdentity();
         try {