Improve how LockSettingsService cleans up stale user (066ce2f7) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/locksettings/LockSettingsService.java

+43 −4

Original line number	Diff line number	Diff line
		@@ -181,6 +181,7 @@ public class LockSettingsService extends ILockSettings.Stub {
		private static final String SEPARATE_PROFILE_CHALLENGE_KEY = "lockscreen.profilechallenge";
		private static final String PREV_SYNTHETIC_PASSWORD_HANDLE_KEY = "prev-sp-handle";
		private static final String SYNTHETIC_PASSWORD_UPDATE_TIME_KEY = "sp-handle-ts";
		private static final String USER_SERIAL_NUMBER_KEY = "serial-number";

		// No challenge provided
		private static final int CHALLENGE_NONE = 0;
		@@ -660,6 +661,34 @@ public class LockSettingsService extends ILockSettings.Stub {
		maybeShowEncryptionNotificationForUser(userId);
		}

		/**
		* Clean up states associated with the given user, in case the userId is reused but LSS didn't
		* get a chance to do cleanup previously during ACTION_USER_REMOVED.
		*
		* Internally, LSS stores serial number for each user and check it against the current user's
		* serial number to determine if the userId is reused and invoke cleanup code.
		*/
		private void cleanupDataForReusedUserIdIfNecessary(int userId) {
		if (userId == UserHandle.USER_SYSTEM) {
		// Short circuit as we never clean up user 0.
		return;
		}
		// Serial number is never reusued, so we can use it as a distinguisher for user Id reuse.
		int serialNumber = mUserManager.getUserSerialNumber(userId);

		int storedSerialNumber = getIntUnchecked(USER_SERIAL_NUMBER_KEY, -1, userId);
		if (storedSerialNumber != serialNumber) {
		// If LockSettingsStorage does not have a copy of the serial number, it could be either
		// this is a user created before the serial number recording logic is introduced, or
		// the user does not exist or was removed and cleaned up properly. In either case, don't
		// invoke removeUser().
		if (storedSerialNumber != -1) {
		removeUser(userId, /* unknownUser */ true);
		}
		setIntUnchecked(USER_SERIAL_NUMBER_KEY, serialNumber, userId);
		}
		}

		/**
		* Check if profile got unlocked but the keystore is still locked. This happens on full disk
		* encryption devices since the profile may not yet be running when we consider unlocking it
		@@ -684,6 +713,7 @@ public class LockSettingsService extends ILockSettings.Stub {
		mHandler.post(new Runnable() {
		@Override
		public void run() {
		cleanupDataForReusedUserIdIfNecessary(userId);
		ensureProfileKeystoreUnlocked(userId);
		// Hide notification first, as tie managed profile lock takes time
		hideEncryptionNotification(new UserHandle(userId));
		@@ -729,9 +759,6 @@ public class LockSettingsService extends ILockSettings.Stub {
		if (Intent.ACTION_USER_ADDED.equals(intent.getAction())) {
		// Notify keystore that a new user was added.
		final int userHandle = intent.getIntExtra(Intent.EXTRA_USER_HANDLE, 0);
		if (userHandle > UserHandle.USER_SYSTEM) {
		removeUser(userHandle, /* unknownUser= */ true);
		}
		final KeyStore ks = KeyStore.getInstance();
		final UserInfo parentInfo = mUserManager.getProfileParent(userHandle);
		final int parentHandle = parentInfo != null ? parentInfo.id : -1;
		@@ -1066,6 +1093,10 @@ public class LockSettingsService extends ILockSettings.Stub {
		setStringUnchecked(key, userId, Long.toString(value));
		}

		private void setIntUnchecked(String key, int value, int userId) {
		setStringUnchecked(key, userId, Integer.toString(value));
		}

		@Override
		public void setString(String key, String value, int userId) {
		checkWritePermission(userId);
		@@ -1104,6 +1135,11 @@ public class LockSettingsService extends ILockSettings.Stub {
		return TextUtils.isEmpty(value) ? defaultValue : Long.parseLong(value);
		}

		private int getIntUnchecked(String key, int defaultValue, int userId) {
		String value = getStringUnchecked(key, null, userId);
		return TextUtils.isEmpty(value) ? defaultValue : Integer.parseInt(value);
		}

		@Override
		public String getString(String key, String defaultValue, int userId) {
		checkReadPermission(key, userId);
		@@ -2171,8 +2207,8 @@ public class LockSettingsService extends ILockSettings.Stub {
		}

		private void removeUser(int userId, boolean unknownUser) {
		Slog.i(TAG, "RemoveUser: " + userId);
		mSpManager.removeUser(userId);
		mStorage.removeUser(userId);
		mStrongAuth.removeUser(userId);
		tryRemoveUserFromSpCacheLater(userId);

		@@ -2183,6 +2219,9 @@ public class LockSettingsService extends ILockSettings.Stub {
		if (unknownUser \|\| mUserManager.getUserInfo(userId).isManagedProfile()) {
		removeKeystoreProfileKey(userId);
		}
		// Clean up storage last, this is to ensure that cleanupDataForReusedUserIdIfNecessary()
		// can make the assumption that no USER_SERIAL_NUMBER_KEY means user is fully removed.
		mStorage.removeUser(userId);
		}

		private void removeKeystoreProfileKey(int targetUserId) {