From 6d74942719bfedfe25f8c20af6fdd726ca14e15e Mon Sep 17 00:00:00 2001
From: Nikita Ioffe <ioffe@google.com>
Date: Tue, 14 Jan 2020 22:19:01 +0000
Subject: [PATCH] Add shell commands to start checkpoint/check it is supported

Test: adb shell sm supports-checkpoint
Test: adb shell sm start-checkpoint 1 && adb reboot
Bug: 135984674
Change-Id: I08cd675b147cea88ad5b29ab4b0cd64ac445879d
---
 cmds/sm/src/com/android/commands/sm/Sm.java   | 29 +++++++++++++++++++
 .../android/server/StorageManagerService.java |  6 ++--
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/cmds/sm/src/com/android/commands/sm/Sm.java b/cmds/sm/src/com/android/commands/sm/Sm.java
index 6033655c8513c..c2ee6dcd13b24 100644
--- a/cmds/sm/src/com/android/commands/sm/Sm.java
+++ b/cmds/sm/src/com/android/commands/sm/Sm.java
@@ -103,6 +103,10 @@ public final class Sm {
             runSetVirtualDisk();
         } else if ("set-isolated-storage".equals(op)) {
             runIsolatedStorage();
+        } else if ("start-checkpoint".equals(op)) {
+            runStartCheckpoint();
+        } else if ("supports-checkpoint".equals(op)) {
+            runSupportsCheckpoint();
         } else {
             throw new IllegalArgumentException();
         }
@@ -313,6 +317,27 @@ public final class Sm {
         }
     }
 
+    private void runStartCheckpoint() throws RemoteException {
+        final String numRetriesString = nextArg();
+        if (numRetriesString == null) {
+            throw new IllegalArgumentException("Expected <num-retries>");
+        }
+        int numRetries;
+        try {
+            numRetries = Integer.parseInt(numRetriesString);
+        } catch (NumberFormatException e) {
+            throw new IllegalArgumentException("<num-retries> must be a positive integer");
+        }
+        if (numRetries <= 0) {
+            throw new IllegalArgumentException("<num-retries> must be a positive integer");
+        }
+        mSm.startCheckpoint(numRetries);
+    }
+
+    private void runSupportsCheckpoint() throws RemoteException {
+        System.out.println(mSm.supportsCheckpoint());
+    }
+
     private String nextArg() {
         if (mNextArg >= mArgs.length) {
             return null;
@@ -344,6 +369,10 @@ public final class Sm {
         System.err.println("");
         System.err.println("       sm set-isolated-storage [on|off|default]");
         System.err.println("");
+        System.err.println("       sm start-checkpoint <num-retries>");
+        System.err.println("");
+        System.err.println("       sm supports-checkpoint");
+        System.err.println("");
         return 1;
     }
 }
diff --git a/services/core/java/com/android/server/StorageManagerService.java b/services/core/java/com/android/server/StorageManagerService.java
index db542145a750d..396b9772fd12f 100644
--- a/services/core/java/com/android/server/StorageManagerService.java
+++ b/services/core/java/com/android/server/StorageManagerService.java
@@ -2855,8 +2855,10 @@ class StorageManagerService extends IStorageManager.Stub
      */
     @Override
     public void startCheckpoint(int numTries) throws RemoteException {
-        // Only the system process is permitted to start checkpoints
-        if (Binder.getCallingUid() != android.os.Process.SYSTEM_UID) {
+        // Only the root, system_server and shell processes are permitted to start checkpoints
+        final int callingUid = Binder.getCallingUid();
+        if (callingUid != Process.SYSTEM_UID && callingUid != Process.ROOT_UID
+                && callingUid != Process.SHELL_UID) {
             throw new SecurityException("no permission to start filesystem checkpoint");
         }