From 8a2b96bb0a1d901beb9cc9635c1fe9a265799b36 Mon Sep 17 00:00:00 2001
From: Yohei Yukawa <yukawa@google.com>
Date: Fri, 28 Dec 2018 17:23:29 -0800
Subject: [PATCH] Clarify shell/root users also have DUMP permission

This is a follow up CL to my previous CL [1], which aimed to
streamline and centralize when and how caller verifications are
performed inside InputMethodManagerService#onShellCommand().

The goal of this change is just to make it clear that shell/root users
also have DUMP permission.  There should be no behavior change as long
as those users have DUMP permission because IMMS#onShellCommand() is
already locked down to accept IPCs only from these two UIDs [2].

The point is that ShellCommand#handleDefaultCommands() by default
dispatches 'dump' command to Binder#doDump() method.  Thus it would
make sense to clarify that DUMP permission is also granted to
shell/root users for completeness.

 [1]: I6fd47b5cc1e7da7222774df20247a2c69a70f45b
      db25df71be4c1bcc654f69ce9a8bff7e3ef46360
 [2]: If87189563ccaacd4f9c666bab4f9ad08a9343084
      b8d240fa3f96b7b4ea35dd271beda789044d63ab

Bug: 34886274
Test: 'adb shell cmd input_method dump' still work
Change-Id: If91137e0c144d90ac3046f30607e36bb957a7e0e
---
 .../inputmethod/InputMethodManagerService.java      | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java b/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
index 99979c18b5201..3364e2818608d 100644
--- a/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
+++ b/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
@@ -4624,17 +4624,20 @@ public class InputMethodManagerService extends IInputMethodManager.Stub
         }
 
         @RequiresPermission(allOf = {
+                Manifest.permission.DUMP,
+                Manifest.permission.INTERACT_ACROSS_USERS_FULL,
                 Manifest.permission.WRITE_SECURE_SETTINGS,
-                Manifest.permission.INTERACT_ACROSS_USERS_FULL})
+        })
         @BinderThread
         @ShellCommandResult
         @Override
         public int onCommand(@Nullable String cmd) {
             // For shell command, require all the permissions here in favor of code simplicity.
-            mService.mContext.enforceCallingPermission(
-                    Manifest.permission.INTERACT_ACROSS_USERS_FULL, null);
-            mService.mContext.enforceCallingPermission(
-                    Manifest.permission.WRITE_SECURE_SETTINGS, null);
+            Arrays.asList(
+                    Manifest.permission.DUMP,
+                    Manifest.permission.INTERACT_ACROSS_USERS_FULL,
+                    Manifest.permission.WRITE_SECURE_SETTINGS
+            ).forEach(permission -> mService.mContext.enforceCallingPermission(permission, null));
 
             final long identity = Binder.clearCallingIdentity();
             try {