commit a72e674e53266d4f500a2d3fe657956d8ed868f7
author Patrick Baumann <patb@google.com> Wed Nov 06 08:26:56 2019 -0800
committer Patrick Baumann <patb@google.com> Fri Nov 08 09:43:31 2019 -0800
tree 9ca104ea4616c50f66a530837cec61dd5a254994
parent 88318e055a8c2878ae11bbe7661ece9389247ec1

Honor shared users in visibility calculations

This change allows apps with the same app id to see each other (members
of the same shared uid, for example) and allows apps targetting an app
in a shared uid to see all of its members.

Bug: 136675067
Test: atest AppEnumerationTests
Change-Id: Ic56c3ff56780828af67210a54968ddaba3aff3d1

services/core/java/com/android/server/pm/AppsFilter.java

diff --git a/services/core/java/com/android/server/pm/AppsFilter.java b/services/core/java/com/android/server/pm/AppsFilter.java
index 31efed4..bb5b04a 100644
--- a/services/core/java/com/android/server/pm/AppsFilter.java
+++ b/services/core/java/com/android/server/pm/AppsFilter.java
@@ -445,8 +445,31 @@
 
     private boolean shouldFilterApplicationInternal(
             PackageSetting callingPkgSetting, PackageSetting targetPkgSetting, int userId) {
+        return shouldFilterApplicationInternal(callingPkgSetting, targetPkgSetting, userId,
+                true /*expandSharedUser*/);
+    }
+
+    /**
+     * @param expandSharedUser true if all members of the shared user a target may belong to should
+     *                         be considered
+     */
+    private boolean shouldFilterApplicationInternal(
+            PackageSetting callingPkgSetting, PackageSetting targetPkgSetting, int userId,
+            boolean expandSharedUser) {
         Trace.traceBegin(TRACE_TAG_PACKAGE_MANAGER, "shouldFilterApplicationInternal");
         try {
+            // special case shared user targets
+            if (expandSharedUser && targetPkgSetting.sharedUser != null) {
+                for (PackageSetting sharedMemberSetting : targetPkgSetting.sharedUser.packages) {
+                    if (!shouldFilterApplicationInternal(
+                            callingPkgSetting, sharedMemberSetting, userId,
+                            false /*expandSharedUser*/)) {
+                        return false;
+                    }
+                }
+                return true;
+            }
+
             final String callingName = callingPkgSetting.pkg.packageName;
             final PackageParser.Package targetPkg = targetPkgSetting.pkg;
 
@@ -471,6 +494,12 @@
                 }
                 return false;
             }
+            if (callingPkgSetting.appId == targetPkgSetting.appId) {
+                if (DEBUG_LOGGING) {
+                    log(callingPkgSetting, targetPkgSetting, "same app id");
+                }
+                return false;
+            }
             if (isImplicitlyQueryableSystemApp(targetPkgSetting)) {
                 if (DEBUG_LOGGING) {
                     log(callingPkgSetting, targetPkgSetting, "implicitly queryable sys");