From 55f6a873458b72b99364d531e9e0cd54236f1cc1 Mon Sep 17 00:00:00 2001
From: Adrian Roos <roosa@google.com>
Date: Tue, 24 May 2022 16:57:47 +0200
Subject: [PATCH] Prevent IMEs from switching to another IME that isn't enabled

Fixes an issue where the current IME can switch to any IME,
even if it hasn't been enabled.

Fixes: 227207653
Test: atest android.view.inputmethod.cts.InputMethodServiceTest
Change-Id: I12829de9fa58610a7d53e4b154e1550f0f791e75
---
 .../server/inputmethod/InputMethodManagerService.java      | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java b/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
index 8cf0ab7441243..99757d955863b 100644
--- a/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
+++ b/services/core/java/com/android/server/inputmethod/InputMethodManagerService.java
@@ -4710,6 +4710,13 @@ public final class InputMethodManagerService extends IInputMethodManager.Stub
             Slog.w(TAG, "Ignoring setInputMethod of uid " + Binder.getCallingUid()
                     + " token: " + token);
             return;
+        } else {
+            // Called with current IME's token.
+            if (mMethodMap.get(id) != null
+                    && mSettings.getEnabledInputMethodListWithFilterLocked(
+                            (info) -> info.getId().equals(id)).isEmpty()) {
+                throw new IllegalStateException("Requested IME is not enabled: " + id);
+            }
         }
 
         final long ident = Binder.clearCallingIdentity();