From a52c9d90cb1e70ca777265c6ca565c13ff4e0d04 Mon Sep 17 00:00:00 2001
From: Jeff Sharkey <jsharkey@android.com>
Date: Mon, 27 Jun 2016 17:27:43 -0600
Subject: [PATCH] Ignore serial number checks when emulating FBE.

When emulating FBE, we may have chmod 000'ed the directory to emulate
it being locked, which results in us failing to read the serial
number, causing a unintentional data wipe.

To avoid this, ignore the serial number check when emulating FBE,
which is a developer-only feature.

Bug: 29231715
Change-Id: Idb056ab378174004d1430b5e7c20db17de28231e
---
 .../java/com/android/server/pm/UserManagerService.java    | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/services/core/java/com/android/server/pm/UserManagerService.java b/services/core/java/com/android/server/pm/UserManagerService.java
index 627cdd0161154..681bf15832b94 100644
--- a/services/core/java/com/android/server/pm/UserManagerService.java
+++ b/services/core/java/com/android/server/pm/UserManagerService.java
@@ -2947,6 +2947,14 @@ public class UserManagerService extends IUserManager.Stub {
      *             number is mismatched.
      */
     public static void enforceSerialNumber(File file, int serialNumber) throws IOException {
+        if (StorageManager.isFileEncryptedEmulatedOnly()) {
+            // When we're emulating FBE, the directory may have been chmod
+            // 000'ed, meaning we can't read the serial number to enforce it;
+            // instead of destroying the user, just log a warning.
+            Slog.w(LOG_TAG, "Device is emulating FBE; assuming current serial number is valid");
+            return;
+        }
+
         final int foundSerial = getSerialNumber(file);
         Slog.v(LOG_TAG, "Found " + file + " with serial number " + foundSerial);