From fb43352f1c853eb51ce8ba4922ec75a452f0b1de Mon Sep 17 00:00:00 2001
From: Jackal Guo <jackalguo@google.com>
Date: Mon, 22 Feb 2021 11:32:42 +0800
Subject: [PATCH] Enfore cross-user permission to getPackagesForUid

Apps could use getPackagesForUid with given UID to query if there
is a installed and get its package name across user. Expect for
package visibility filtering, we also need to ensure across-user
calls come with appropriate permission.

Bug: 167654926
Test: atest ApplicationVisibilityTest
Change-Id: I435e0160128591b50ddd5998e7c558b78aaca9b1
---
 .../java/com/android/server/pm/PackageManagerService.java    | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
index 16966d4de4e62..b9828e20db1f5 100644
--- a/services/core/java/com/android/server/pm/PackageManagerService.java
+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -9167,6 +9167,11 @@ public class PackageManagerService extends IPackageManager.Stub
      */
     @Override
     public String[] getPackagesForUid(int uid) {
+        final int callingUid = Binder.getCallingUid();
+        final int userId = UserHandle.getUserId(uid);
+        enforceCrossUserOrProfilePermission(callingUid, userId,
+                /* requireFullPermission */ false,
+                /* checkShell */ false, "getPackagesForUid");
         return snapshotComputer().getPackagesForUid(uid);
     }