ActivityManager shouldn't return null for getCurrentUser
There was a race where ActivityManager would return null
for getCurrentUser() when switching between guest accounts.
This is because the Guest account was marked for deletion
while it was still active.
Bug:17290209
Change-Id: I224fb4b6836380e5acb7dbeb8f3343d74505f88a
diff --git a/services/core/java/com/android/server/pm/UserManagerService.java b/services/core/java/com/android/server/pm/UserManagerService.java
index 4a2cece..53d8ed0 100644
--- a/services/core/java/com/android/server/pm/UserManagerService.java
+++ b/services/core/java/com/android/server/pm/UserManagerService.java
@@ -21,7 +21,6 @@
import android.app.Activity;
import android.app.ActivityManager;
import android.app.ActivityManagerNative;
-import android.app.ActivityThread;
import android.app.IStopUserCallback;
import android.content.BroadcastReceiver;
import android.content.Context;
@@ -92,6 +91,7 @@
private static final String ATTR_SERIAL_NO = "serialNumber";
private static final String ATTR_NEXT_SERIAL_NO = "nextSerialNumber";
private static final String ATTR_PARTIAL = "partial";
+ private static final String ATTR_GUEST_TO_REMOVE = "guestToRemove";
private static final String ATTR_USER_VERSION = "version";
private static final String ATTR_PROFILE_GROUP_ID = "profileGroupId";
private static final String TAG_GUEST_RESTRICTIONS = "guestRestrictions";
@@ -228,7 +228,7 @@
ArrayList<UserInfo> partials = new ArrayList<UserInfo>();
for (int i = 0; i < mUsers.size(); i++) {
UserInfo ui = mUsers.valueAt(i);
- if (ui.partial && i != 0) {
+ if ((ui.partial || ui.guestToRemove) && i != 0) {
partials.add(ui);
}
}
@@ -759,6 +759,9 @@
if (userInfo.partial) {
serializer.attribute(null, ATTR_PARTIAL, "true");
}
+ if (userInfo.guestToRemove) {
+ serializer.attribute(null, ATTR_GUEST_TO_REMOVE, "true");
+ }
if (userInfo.profileGroupId != UserInfo.NO_PROFILE_GROUP_ID) {
serializer.attribute(null, ATTR_PROFILE_GROUP_ID,
Integer.toString(userInfo.profileGroupId));
@@ -806,7 +809,7 @@
serializer.attribute(null, ATTR_NEXT_SERIAL_NO, Integer.toString(mNextSerialNumber));
serializer.attribute(null, ATTR_USER_VERSION, Integer.toString(mUserVersion));
- serializer.startTag(null, TAG_GUEST_RESTRICTIONS);
+ serializer.startTag(null, TAG_GUEST_RESTRICTIONS);
writeRestrictionsLocked(serializer, mGuestRestrictions);
serializer.endTag(null, TAG_GUEST_RESTRICTIONS);
for (int i = 0; i < mUsers.size(); i++) {
@@ -871,6 +874,7 @@
int profileGroupId = UserInfo.NO_PROFILE_GROUP_ID;
long lastAttemptTime = 0L;
boolean partial = false;
+ boolean guestToRemove = false;
Bundle restrictions = new Bundle();
FileInputStream fis = null;
@@ -918,6 +922,10 @@
if ("true".equals(valueString)) {
partial = true;
}
+ valueString = parser.getAttributeValue(null, ATTR_GUEST_TO_REMOVE);
+ if ("true".equals(valueString)) {
+ guestToRemove = true;
+ }
int outerDepth = parser.getDepth();
while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
@@ -942,6 +950,7 @@
userInfo.creationTime = creationTime;
userInfo.lastLoggedInTime = lastLoggedInTime;
userInfo.partial = partial;
+ userInfo.guestToRemove = guestToRemove;
userInfo.profileGroupId = profileGroupId;
mUserRestrictions.append(id, restrictions);
if (salt != 0L) {
@@ -1119,7 +1128,7 @@
return null;
}
// If we're adding a guest and there already exists one, bail.
- if (isGuest && numberOfUsersOfTypeLocked(UserInfo.FLAG_GUEST, true) > 0) {
+ if (isGuest && findCurrentGuestUserLocked() != null) {
return null;
}
// Limit number of managed profiles that can be created
@@ -1180,6 +1189,23 @@
}
/**
+ * Find the current guest user. If the Guest user is partial,
+ * then do not include it in the results as it is about to die.
+ * This is different than {@link #numberOfUsersOfTypeLocked(int, boolean)} due to
+ * the special handling of Guests being removed.
+ */
+ private UserInfo findCurrentGuestUserLocked() {
+ final int size = mUsers.size();
+ for (int i = 0; i < size; i++) {
+ final UserInfo user = mUsers.valueAt(i);
+ if (user.isGuest() && !user.guestToRemove && !mRemovingUserIds.get(user.id)) {
+ return user;
+ }
+ }
+ return null;
+ }
+
+ /**
* Mark this guest user for deletion to allow us to create another guest
* and switch to that user before actually removing this guest.
* @param userHandle the userid of the current guest
@@ -1204,14 +1230,15 @@
if (!user.isGuest()) {
return false;
}
- // Set this to a partially created user, so that the user will be purged
- // on next startup, in case the runtime stops now before stopping and
- // removing the user completely.
- user.partial = true;
+ // We set this to a guest user that is to be removed. This is a temporary state
+ // where we are allowed to add new Guest users, even if this one is still not
+ // removed. This user will still show up in getUserInfo() calls.
+ // If we don't get around to removing this Guest user, it will be purged on next
+ // startup.
+ user.guestToRemove = true;
// Mark it as disabled, so that it isn't returned any more when
// profiles are queried.
user.flags |= UserInfo.FLAG_DISABLED;
- user.flags &= ~UserInfo.FLAG_GUEST;
writeUserLocked(user);
}
} finally {