From c3f4dd070cfc7f20581779abd83620fc8769fbd4 Mon Sep 17 00:00:00 2001 From: Hongwei Wang Date: Tue, 1 Aug 2023 16:00:31 -0700 Subject: Rate limiting PiP aspect ratio change request Using CountQuotaTrack to limit how frequent an app can request aspect ratio change via PictureInPictureParams, which could result flood of PiP resizing requests and freeze the PiP window. Note that CountQuotaTrack is initialized out of the WM lock to avoid dead lock with the AM one. Bug: 283103220 Test: Manually, using the POC app Test: Manually, switching YT PiP video functions at a regular rate Test: atest WindowOrganizerTests ActivityThreadTest Merged-In: Icb7dd17bbf7df573a9bb28f3dc56e90e78384f4f Change-Id: Icb7dd17bbf7df573a9bb28f3dc56e90e78384f4f --- .../server/wm/ActivityClientController.java | 39 ++++++++++++++++++++++ .../android/server/wm/WindowOrganizerTests.java | 6 ++++ 2 files changed, 45 insertions(+) diff --git a/services/core/java/com/android/server/wm/ActivityClientController.java b/services/core/java/com/android/server/wm/ActivityClientController.java index e02e8671f211..c783630be113 100644 --- a/services/core/java/com/android/server/wm/ActivityClientController.java +++ b/services/core/java/com/android/server/wm/ActivityClientController.java @@ -73,6 +73,7 @@ import android.util.Slog; import android.view.RemoteAnimationDefinition; import android.window.SizeConfigurationBuckets; +import com.android.internal.annotations.VisibleForTesting; import com.android.internal.app.AssistUtils; import com.android.internal.policy.IKeyguardDismissCallback; import com.android.internal.protolog.common.ProtoLog; @@ -80,6 +81,9 @@ import com.android.server.LocalServices; import com.android.server.Watchdog; import com.android.server.pm.parsing.pkg.AndroidPackage; import com.android.server.uri.NeededUriGrants; +import com.android.server.utils.quota.Categorizer; +import com.android.server.utils.quota.Category; +import com.android.server.utils.quota.CountQuotaTracker; import com.android.server.vr.VrManagerInternal; /** @@ -95,6 +99,13 @@ class ActivityClientController extends IActivityClientController.Stub { private final ActivityTaskSupervisor mTaskSupervisor; private final Context mContext; + // Prevent malicious app abusing the Activity#setPictureInPictureParams API + @VisibleForTesting CountQuotaTracker mSetPipAspectRatioQuotaTracker; + // Limit to 60 times / minute + private static final int SET_PIP_ASPECT_RATIO_LIMIT = 60; + // The timeWindowMs here can not be smaller than QuotaTracker#MIN_WINDOW_SIZE_MS + private static final long SET_PIP_ASPECT_RATIO_TIME_WINDOW_MS = 60_000; + /** Wrapper around VoiceInteractionServiceManager. */ private AssistUtils mAssistUtils; @@ -691,6 +702,7 @@ class ActivityClientController extends IActivityClientController.Stub { public boolean enterPictureInPictureMode(IBinder token, final PictureInPictureParams params) { final long origId = Binder.clearCallingIdentity(); try { + ensureSetPipAspectRatioQuotaTracker(); synchronized (mGlobalLock) { final ActivityRecord r = ensureValidPictureInPictureActivityParams( "enterPictureInPictureMode", token, params); @@ -705,6 +717,7 @@ class ActivityClientController extends IActivityClientController.Stub { public void setPictureInPictureParams(IBinder token, final PictureInPictureParams params) { final long origId = Binder.clearCallingIdentity(); try { + ensureSetPipAspectRatioQuotaTracker(); synchronized (mGlobalLock) { final ActivityRecord r = ensureValidPictureInPictureActivityParams( "setPictureInPictureParams", token, params); @@ -738,6 +751,19 @@ class ActivityClientController extends IActivityClientController.Stub { Binder.restoreCallingIdentity(origId); } + /** + * Initialize the {@link #mSetPipAspectRatioQuotaTracker} if applicable, which should happen + * out of {@link #mGlobalLock} to avoid deadlock (AM lock is used in QuotaTrack ctor). + */ + private void ensureSetPipAspectRatioQuotaTracker() { + if (mSetPipAspectRatioQuotaTracker == null) { + mSetPipAspectRatioQuotaTracker = new CountQuotaTracker(mContext, + Categorizer.SINGLE_CATEGORIZER); + mSetPipAspectRatioQuotaTracker.setCountLimit(Category.SINGLE_CATEGORY, + SET_PIP_ASPECT_RATIO_LIMIT, SET_PIP_ASPECT_RATIO_TIME_WINDOW_MS); + } + } + /** * Checks the state of the system and the activity associated with the given {@param token} to * verify that picture-in-picture is supported for that activity. @@ -762,6 +788,19 @@ class ActivityClientController extends IActivityClientController.Stub { + ": Current activity does not support picture-in-picture."); } + // Rate limit how frequent an app can request aspect ratio change via + // Activity#setPictureInPictureParams + final int userId = UserHandle.getCallingUserId(); + if (r.pictureInPictureArgs.hasSetAspectRatio() + && params.hasSetAspectRatio() + && !r.pictureInPictureArgs.getAspectRatioRational().equals( + params.getAspectRatioRational()) + && !mSetPipAspectRatioQuotaTracker.noteEvent( + userId, r.packageName, "setPipAspectRatio")) { + throw new IllegalStateException(caller + + ": Too many PiP aspect ratio change requests from " + r.packageName); + } + if (params.hasSetAspectRatio() && !mService.mWindowManager.isValidPictureInPictureAspectRatio( r.mDisplayContent, params.getAspectRatio())) { diff --git a/services/tests/wmtests/src/com/android/server/wm/WindowOrganizerTests.java b/services/tests/wmtests/src/com/android/server/wm/WindowOrganizerTests.java index ab496cf34acc..cb1a69339044 100644 --- a/services/tests/wmtests/src/com/android/server/wm/WindowOrganizerTests.java +++ b/services/tests/wmtests/src/com/android/server/wm/WindowOrganizerTests.java @@ -851,6 +851,12 @@ public class WindowOrganizerTests extends WindowTestsBase { assertNotNull(o.mInfo); assertNotNull(o.mInfo.pictureInPictureParams); + // Bypass the quota check, which causes NPE in current test setup. + if (mWm.mAtmService.mActivityClientController.mSetPipAspectRatioQuotaTracker != null) { + mWm.mAtmService.mActivityClientController.mSetPipAspectRatioQuotaTracker + .setEnabled(false); + } + final PictureInPictureParams p2 = new PictureInPictureParams.Builder() .setAspectRatio(new Rational(3, 4)).build(); mWm.mAtmService.mActivityClientController.setPictureInPictureParams(record.token, p2); -- cgit v1.2.3-59-g8ed1b