Defuse Bundles parsed by the system process.

It's easy for apps to throw custom Parcelables into Bundles, but
if the system tries peeking inside one of these Bundles, it triggers
a BadParcelableException.  If that Bundle was passed away from the
Binder thread that delivered it into the system, we end up with a
nasty runtime restart.

This change mitigates this trouble by "defusing" any Bundles parsed by
the system server.  That is, if it encounters BadParcelableException
while unpacking a Bundle, it logs and delivers an empty Bundle as
the result.

Simultaneously, to help catch the system process sticking its
fingers into Bundles that are destined for other processes, a Bundle
now tracks if it's "defusable."  For example, any Intents delivered
through ActivityThread are marked as being defusable, since they've
arrived at their final destination.  Any other Bundles are considered
to be "in transit" and we log if the system tries unparceling them.

Merges several Parcel boolean fields into a flags int.  Add better
docs to several classes.

Bug: 27581063
Change-Id: I28cf3e7439503b5dc9a429bafae5eb48f21f0d93
diff --git a/core/java/android/app/ActivityOptions.java b/core/java/android/app/ActivityOptions.java
index f178455..a6e7d67 100644
--- a/core/java/android/app/ActivityOptions.java
+++ b/core/java/android/app/ActivityOptions.java
@@ -710,6 +710,10 @@
 
     /** @hide */
     public ActivityOptions(Bundle opts) {
+        // If the remote side sent us bad parcelables, they won't get the
+        // results they want, which is their loss.
+        opts.setDefusable(true);
+
         mPackageName = opts.getString(KEY_PACKAGE_NAME);
         try {
             mUsageTimeReport = opts.getParcelable(KEY_USAGE_TIME_REPORT);
diff --git a/core/java/android/app/ContextImpl.java b/core/java/android/app/ContextImpl.java
index 32ace14..4fccbc9 100644
--- a/core/java/android/app/ContextImpl.java
+++ b/core/java/android/app/ContextImpl.java
@@ -1332,9 +1332,14 @@
             }
         }
         try {
-            return ActivityManagerNative.getDefault().registerReceiver(
+            final Intent intent = ActivityManagerNative.getDefault().registerReceiver(
                     mMainThread.getApplicationThread(), mBasePackageName,
                     rd, filter, broadcastPermission, userId);
+            if (intent != null) {
+                intent.setExtrasClassLoader(getClassLoader());
+                intent.prepareToEnterProcess();
+            }
+            return intent;
         } catch (RemoteException e) {
             throw e.rethrowFromSystemServer();
         }
diff --git a/core/java/android/app/LoadedApk.java b/core/java/android/app/LoadedApk.java
index a03fd72..c68fd65 100644
--- a/core/java/android/app/LoadedApk.java
+++ b/core/java/android/app/LoadedApk.java
@@ -913,6 +913,8 @@
                 mDispatcher = new WeakReference<LoadedApk.ReceiverDispatcher>(rd);
                 mStrongRef = strong ? rd : null;
             }
+
+            @Override
             public void performReceive(Intent intent, int resultCode, String data,
                     Bundle extras, boolean ordered, boolean sticky, int sendingUser) {
                 LoadedApk.ReceiverDispatcher rd = mDispatcher.get();
@@ -996,6 +998,7 @@
                 try {
                     ClassLoader cl =  mReceiver.getClass().getClassLoader();
                     intent.setExtrasClassLoader(cl);
+                    intent.prepareToEnterProcess();
                     setExtrasClassLoader(cl);
                     receiver.setPendingResult(this);
                     receiver.onReceive(mContext, intent);
diff --git a/core/java/android/content/ClipData.java b/core/java/android/content/ClipData.java
index 0ec58ea..58630b0 100644
--- a/core/java/android/content/ClipData.java
+++ b/core/java/android/content/ClipData.java
@@ -836,6 +836,17 @@
         }
     }
 
+    /** {@hide} */
+    public void prepareToEnterProcess() {
+        final int size = mItems.size();
+        for (int i = 0; i < size; i++) {
+            final Item item = mItems.get(i);
+            if (item.mIntent != null) {
+                item.mIntent.prepareToEnterProcess();
+            }
+        }
+    }
+
     /** @hide */
     public void fixUris(int contentUserHint) {
         final int size = mItems.size();
diff --git a/core/java/android/content/Intent.java b/core/java/android/content/Intent.java
index 35dbc34..09aad3b 100644
--- a/core/java/android/content/Intent.java
+++ b/core/java/android/content/Intent.java
@@ -6037,13 +6037,20 @@
         return mExtras != null && mExtras.hasFileDescriptors();
     }
 
-    /** @hide */
+    /** {@hide} */
     public void setAllowFds(boolean allowFds) {
         if (mExtras != null) {
             mExtras.setAllowFds(allowFds);
         }
     }
 
+    /** {@hide} */
+    public void setDefusable(boolean defusable) {
+        if (mExtras != null) {
+            mExtras.setDefusable(defusable);
+        }
+    }
+
     /**
      * Retrieve extended data from the intent.
      *
@@ -8938,6 +8945,17 @@
      * @hide
      */
     public void prepareToEnterProcess() {
+        // We just entered destination process, so we should be able to read all
+        // parcelables inside.
+        setDefusable(true);
+
+        if (mSelector != null) {
+            mSelector.prepareToEnterProcess();
+        }
+        if (mClipData != null) {
+            mClipData.prepareToEnterProcess();
+        }
+
         if (mContentUserHint != UserHandle.USER_CURRENT) {
             if (UserHandle.getAppId(Process.myUid()) != Process.SYSTEM_UID) {
                 fixUris(mContentUserHint);
diff --git a/core/java/android/os/BadParcelableException.java b/core/java/android/os/BadParcelableException.java
index a1c5bb2..7e0b1a5 100644
--- a/core/java/android/os/BadParcelableException.java
+++ b/core/java/android/os/BadParcelableException.java
@@ -15,11 +15,15 @@
  */
 
 package android.os;
+
 import android.util.AndroidRuntimeException;
 
 /**
- * The object you are calling has died, because its hosting process
- * no longer exists.
+ * Exception thrown when a {@link Parcelable} is malformed or otherwise invalid.
+ * <p>
+ * This is typically encountered when a custom {@link Parcelable} object is
+ * passed to another process that doesn't have the same {@link Parcelable} class
+ * in its {@link ClassLoader}.
  */
 public class BadParcelableException extends AndroidRuntimeException {
     public BadParcelableException(String msg) {
diff --git a/core/java/android/os/BaseBundle.java b/core/java/android/os/BaseBundle.java
index 5c71373..6e50155 100644
--- a/core/java/android/os/BaseBundle.java
+++ b/core/java/android/os/BaseBundle.java
@@ -26,7 +26,9 @@
 import java.util.Set;
 
 /**
- * A mapping from String values to various types.
+ * A mapping from String keys to values of various types. In most cases, you
+ * should work directly with either the {@link Bundle} or
+ * {@link PersistableBundle} subclass.
  */
 public class BaseBundle {
     private static final String TAG = "Bundle";
@@ -35,6 +37,32 @@
     // Keep in sync with frameworks/native/libs/binder/PersistableBundle.cpp.
     static final int BUNDLE_MAGIC = 0x4C444E42; // 'B' 'N' 'D' 'L'
 
+    /**
+     * Flag indicating that this Bundle is okay to "defuse." That is, it's okay
+     * for system processes to ignore any {@link BadParcelableException}
+     * encountered when unparceling it, leaving an empty bundle in its place.
+     * <p>
+     * This should <em>only</em> be set when the Bundle reaches its final
+     * destination, otherwise a system process may clobber contents that were
+     * destined for an app that could have unparceled them.
+     */
+    static final int FLAG_DEFUSABLE = 1 << 0;
+
+    private static volatile boolean sShouldDefuse = false;
+
+    /**
+     * Set global variable indicating that any Bundles parsed in this process
+     * should be "defused." That is, any {@link BadParcelableException}
+     * encountered will be suppressed and logged, leaving an empty Bundle
+     * instead of crashing.
+     *
+     * @hide
+     */
+    public static void setShouldDefuse(boolean shouldDefuse) {
+        sShouldDefuse = shouldDefuse;
+    }
+
+    /** {@hide} */
     static final Parcel EMPTY_PARCEL;
 
     static {
@@ -58,6 +86,9 @@
      */
     private ClassLoader mClassLoader;
 
+    /** {@hide} */
+    int mFlags;
+
     /**
      * Constructs a new, empty Bundle that uses a specific ClassLoader for
      * instantiating Parcelable and Serializable objects.
@@ -197,6 +228,11 @@
             return;
         }
 
+        if (sShouldDefuse && (mFlags & FLAG_DEFUSABLE) == 0) {
+            Log.wtf(TAG, "Attempting to unparcel a Bundle while in transit; this may "
+                    + "clobber all data inside!", new Throwable());
+        }
+
         if (mParcelledData == EMPTY_PARCEL) {
             if (DEBUG) Log.d(TAG, "unparcel " + Integer.toHexString(System.identityHashCode(this))
                     + ": empty");
@@ -221,9 +257,19 @@
             mMap.erase();
             mMap.ensureCapacity(N);
         }
-        mParcelledData.readArrayMapInternal(mMap, N, mClassLoader);
-        mParcelledData.recycle();
-        mParcelledData = null;
+        try {
+            mParcelledData.readArrayMapInternal(mMap, N, mClassLoader);
+        } catch (BadParcelableException e) {
+            if (sShouldDefuse) {
+                Log.w(TAG, "Failed to parse Bundle, but defusing quietly", e);
+                mMap.erase();
+            } else {
+                throw e;
+            }
+        } finally {
+            mParcelledData.recycle();
+            mParcelledData = null;
+        }
         if (DEBUG) Log.d(TAG, "unparcel " + Integer.toHexString(System.identityHashCode(this))
                 + " final map: " + mMap);
     }
@@ -1371,9 +1417,8 @@
             return;
         }
 
-        int magic = parcel.readInt();
+        final int magic = parcel.readInt();
         if (magic != BUNDLE_MAGIC) {
-            //noinspection ThrowableInstanceNeverThrown
             throw new IllegalStateException("Bad magic number for Bundle: 0x"
                     + Integer.toHexString(magic));
         }
diff --git a/core/java/android/os/Bundle.java b/core/java/android/os/Bundle.java
index 74699fd..f334e77 100644
--- a/core/java/android/os/Bundle.java
+++ b/core/java/android/os/Bundle.java
@@ -27,11 +27,17 @@
 import java.util.List;
 
 /**
- * A mapping from String values to various Parcelable types.
+ * A mapping from String keys to various {@link Parcelable} values.
  *
+ * @see PersistableBundle
  */
 public final class Bundle extends BaseBundle implements Cloneable, Parcelable {
+    private static final int FLAG_HAS_FDS = 1 << 8;
+    private static final int FLAG_HAS_FDS_KNOWN = 1 << 9;
+    private static final int FLAG_ALLOW_FDS = 1 << 10;
+
     public static final Bundle EMPTY;
+
     static final Parcel EMPTY_PARCEL;
 
     static {
@@ -40,15 +46,12 @@
         EMPTY_PARCEL = BaseBundle.EMPTY_PARCEL;
     }
 
-    private boolean mHasFds = false;
-    private boolean mFdsKnown = true;
-    private boolean mAllowFds = true;
-
     /**
      * Constructs a new, empty Bundle.
      */
     public Bundle() {
         super();
+        mFlags = FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -59,16 +62,18 @@
      */
     Bundle(Parcel parcelledData) {
         super(parcelledData);
-
-        mHasFds = mParcelledData.hasFileDescriptors();
-        mFdsKnown = true;
+        mFlags = FLAG_HAS_FDS_KNOWN;
+        if (mParcelledData.hasFileDescriptors()) {
+            mFlags |= FLAG_HAS_FDS;
+        }
     }
 
     /* package */ Bundle(Parcel parcelledData, int length) {
         super(parcelledData, length);
-
-        mHasFds = mParcelledData.hasFileDescriptors();
-        mFdsKnown = true;
+        mFlags = FLAG_HAS_FDS_KNOWN;
+        if (mParcelledData.hasFileDescriptors()) {
+            mFlags |= FLAG_HAS_FDS;
+        }
     }
 
     /**
@@ -80,6 +85,7 @@
      */
     public Bundle(ClassLoader loader) {
         super(loader);
+        mFlags = FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -90,6 +96,7 @@
      */
     public Bundle(int capacity) {
         super(capacity);
+        mFlags = FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -100,9 +107,7 @@
      */
     public Bundle(Bundle b) {
         super(b);
-
-        mHasFds = b.mHasFds;
-        mFdsKnown = b.mFdsKnown;
+        mFlags = b.mFlags;
     }
 
     /**
@@ -113,6 +118,7 @@
      */
     public Bundle(PersistableBundle b) {
         super(b);
+        mFlags = FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -145,14 +151,37 @@
         return super.getClassLoader();
     }
 
-    /** @hide */
+    /** {@hide} */
     public boolean setAllowFds(boolean allowFds) {
-        boolean orig = mAllowFds;
-        mAllowFds = allowFds;
+        final boolean orig = (mFlags & FLAG_ALLOW_FDS) != 0;
+        if (allowFds) {
+            mFlags |= FLAG_ALLOW_FDS;
+        } else {
+            mFlags &= ~FLAG_ALLOW_FDS;
+        }
         return orig;
     }
 
     /**
+     * Mark if this Bundle is okay to "defuse." That is, it's okay for system
+     * processes to ignore any {@link BadParcelableException} encountered when
+     * unparceling it, leaving an empty bundle in its place.
+     * <p>
+     * This should <em>only</em> be set when the Bundle reaches its final
+     * destination, otherwise a system process may clobber contents that were
+     * destined for an app that could have unparceled them.
+     *
+     * @hide
+     */
+    public void setDefusable(boolean defusable) {
+        if (defusable) {
+            mFlags |= FLAG_DEFUSABLE;
+        } else {
+            mFlags &= ~FLAG_DEFUSABLE;
+        }
+    }
+
+    /**
      * Clones the current Bundle. The internal map is cloned, but the keys and
      * values to which it refers are copied by reference.
      */
@@ -167,9 +196,7 @@
     @Override
     public void clear() {
         super.clear();
-
-        mHasFds = false;
-        mFdsKnown = true;
+        mFlags = FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -182,16 +209,20 @@
         bundle.unparcel();
         mMap.putAll(bundle.mMap);
 
-        // fd state is now known if and only if both bundles already knew
-        mHasFds |= bundle.mHasFds;
-        mFdsKnown = mFdsKnown && bundle.mFdsKnown;
+        // FD state is now known if and only if both bundles already knew
+        if ((bundle.mFlags & FLAG_HAS_FDS) != 0) {
+            mFlags |= FLAG_HAS_FDS;
+        }
+        if ((bundle.mFlags & FLAG_HAS_FDS_KNOWN) == 0) {
+            mFlags &= ~FLAG_HAS_FDS_KNOWN;
+        }
     }
 
     /**
      * Reports whether the bundle contains any parcelled file descriptors.
      */
     public boolean hasFileDescriptors() {
-        if (!mFdsKnown) {
+        if ((mFlags & FLAG_HAS_FDS_KNOWN) == 0) {
             boolean fdFound = false;    // keep going until we find one or run out of data
 
             if (mParcelledData != null) {
@@ -247,10 +278,12 @@
                 }
             }
 
-            mHasFds = fdFound;
-            mFdsKnown = true;
+            if (fdFound) {
+                mFlags |= FLAG_HAS_FDS;
+            }
+            mFlags |= FLAG_HAS_FDS_KNOWN;
         }
-        return mHasFds;
+        return (mFlags & FLAG_HAS_FDS) != 0;
     }
 
     /**
@@ -346,7 +379,7 @@
     public void putParcelable(@Nullable String key, @Nullable Parcelable value) {
         unparcel();
         mMap.put(key, value);
-        mFdsKnown = false;
+        mFlags &= ~FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -384,7 +417,7 @@
     public void putParcelableArray(@Nullable String key, @Nullable Parcelable[] value) {
         unparcel();
         mMap.put(key, value);
-        mFdsKnown = false;
+        mFlags &= ~FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -399,14 +432,14 @@
             @Nullable ArrayList<? extends Parcelable> value) {
         unparcel();
         mMap.put(key, value);
-        mFdsKnown = false;
+        mFlags &= ~FLAG_HAS_FDS_KNOWN;
     }
 
     /** {@hide} */
     public void putParcelableList(String key, List<? extends Parcelable> value) {
         unparcel();
         mMap.put(key, value);
-        mFdsKnown = false;
+        mFlags &= ~FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -421,7 +454,7 @@
             @Nullable SparseArray<? extends Parcelable> value) {
         unparcel();
         mMap.put(key, value);
-        mFdsKnown = false;
+        mFlags &= ~FLAG_HAS_FDS_KNOWN;
     }
 
     /**
@@ -1074,7 +1107,7 @@
      */
     @Override
     public void writeToParcel(Parcel parcel, int flags) {
-        final boolean oldAllowFds = parcel.pushAllowFds(mAllowFds);
+        final boolean oldAllowFds = parcel.pushAllowFds((mFlags & FLAG_ALLOW_FDS) != 0);
         try {
             super.writeToParcelInner(parcel, flags);
         } finally {
@@ -1089,8 +1122,10 @@
      */
     public void readFromParcel(Parcel parcel) {
         super.readFromParcelInner(parcel);
-        mHasFds = mParcelledData.hasFileDescriptors();
-        mFdsKnown = true;
+        mFlags = FLAG_HAS_FDS_KNOWN;
+        if (mParcelledData.hasFileDescriptors()) {
+            mFlags |= FLAG_HAS_FDS;
+        }
     }
 
     @Override
@@ -1105,5 +1140,4 @@
         }
         return "Bundle[" + mMap.toString() + "]";
     }
-
 }
diff --git a/core/java/android/os/PersistableBundle.java b/core/java/android/os/PersistableBundle.java
index 5872f74..b947c97 100644
--- a/core/java/android/os/PersistableBundle.java
+++ b/core/java/android/os/PersistableBundle.java
@@ -18,7 +18,9 @@
 
 import android.annotation.Nullable;
 import android.util.ArrayMap;
+
 import com.android.internal.util.XmlUtils;
+
 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserException;
 import org.xmlpull.v1.XmlSerializer;
@@ -26,9 +28,11 @@
 import java.io.IOException;
 
 /**
- * A mapping from String values to various types that can be saved to persistent and later
- * restored.
+ * A mapping from String keys to values of various types. The set of types
+ * supported by this class is purposefully restricted to simple objects that can
+ * safely be persisted to and restored from disk.
  *
+ * @see Bundle
  */
 public final class PersistableBundle extends BaseBundle implements Cloneable, Parcelable,
         XmlUtils.WriteMapCallback {
@@ -57,6 +61,7 @@
      */
     public PersistableBundle() {
         super();
+        mFlags = FLAG_DEFUSABLE;
     }
 
     /**
@@ -67,6 +72,7 @@
      */
     public PersistableBundle(int capacity) {
         super(capacity);
+        mFlags = FLAG_DEFUSABLE;
     }
 
     /**
@@ -77,6 +83,7 @@
      */
     public PersistableBundle(PersistableBundle b) {
         super(b);
+        mFlags = b.mFlags;
     }
 
 
@@ -101,6 +108,7 @@
      */
     private PersistableBundle(ArrayMap<String, Object> map) {
         super();
+        mFlags = FLAG_DEFUSABLE;
 
         // First stuff everything in.
         putAll(map);
@@ -123,6 +131,7 @@
 
     /* package */ PersistableBundle(Parcel parcelledData, int length) {
         super(parcelledData, length);
+        mFlags = FLAG_DEFUSABLE;
     }
 
     /**
@@ -278,5 +287,4 @@
         }
         return "PersistableBundle[" + mMap.toString() + "]";
     }
-
 }
diff --git a/core/java/android/view/WindowManagerGlobal.java b/core/java/android/view/WindowManagerGlobal.java
index a1cbc1d..887cc3a 100644
--- a/core/java/android/view/WindowManagerGlobal.java
+++ b/core/java/android/view/WindowManagerGlobal.java
@@ -170,7 +170,7 @@
                     sWindowManagerService = getWindowManagerService();
                     ValueAnimator.setDurationScale(sWindowManagerService.getCurrentAnimatorScale());
                 } catch (RemoteException e) {
-                    Log.e(TAG, "Failed to get WindowManagerService, cannot set animator scale", e);
+                    throw e.rethrowFromSystemServer();
                 }
             }
             return sWindowManagerService;
@@ -192,7 +192,7 @@
                             },
                             imm.getClient(), imm.getInputContext());
                 } catch (RemoteException e) {
-                    Log.e(TAG, "Failed to open window session", e);
+                    throw e.rethrowFromSystemServer();
                 }
             }
             return sWindowSession;