MTP: Return error if user tries to copy a file >= 4GB to a FAT32 file system

Bug: 4561836

Change-Id: I2bffb93b032038f6c220c24c752ccd7ca66c23a0
Signed-off-by: Mike Lockwood <lockwood@android.com>
diff --git a/core/java/android/os/storage/StorageVolume.java b/core/java/android/os/storage/StorageVolume.java
index 792e4c1..60900e1 100644
--- a/core/java/android/os/storage/StorageVolume.java
+++ b/core/java/android/os/storage/StorageVolume.java
@@ -34,6 +34,8 @@
     private final int mMtpReserveSpace;
     private final boolean mAllowMassStorage;
     private int mStorageId;
+    // maximum file size for the storage, or zero for no limit
+    private final long mMaxFileSize;
 
     // StorageVolume extra for ACTION_MEDIA_REMOVED, ACTION_MEDIA_UNMOUNTED, ACTION_MEDIA_CHECKING,
     // ACTION_MEDIA_NOFS, ACTION_MEDIA_MOUNTED, ACTION_MEDIA_SHARED, ACTION_MEDIA_UNSHARED,
@@ -41,18 +43,20 @@
     public static final String EXTRA_STORAGE_VOLUME = "storage_volume";
 
     public StorageVolume(String path, String description, boolean removable,
-            boolean emulated, int mtpReserveSpace, boolean allowMassStorage) {
+            boolean emulated, int mtpReserveSpace, boolean allowMassStorage, long maxFileSize) {
         mPath = path;
         mDescription = description;
         mRemovable = removable;
         mEmulated = emulated;
         mMtpReserveSpace = mtpReserveSpace;
         mAllowMassStorage = allowMassStorage;
+        mMaxFileSize = maxFileSize;
     }
 
     // for parcelling only
     private StorageVolume(String path, String description, boolean removable,
-            boolean emulated, int mtpReserveSpace, int storageId, boolean allowMassStorage) {
+            boolean emulated, int mtpReserveSpace, int storageId,
+            boolean allowMassStorage, long maxFileSize) {
         mPath = path;
         mDescription = description;
         mRemovable = removable;
@@ -60,6 +64,7 @@
         mMtpReserveSpace = mtpReserveSpace;
         mAllowMassStorage = allowMassStorage;
         mStorageId = storageId;
+        mMaxFileSize = maxFileSize;
     }
 
     /**
@@ -142,6 +147,15 @@
         return mAllowMassStorage;
     }
 
+    /**
+     * Returns maximum file size for the volume, or zero if it is unbounded.
+     *
+     * @return maximum file size
+     */
+    public long getMaxFileSize() {
+        return mMaxFileSize;
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (obj instanceof StorageVolume && mPath != null) {
@@ -171,9 +185,10 @@
             int storageId = in.readInt();
             int mtpReserveSpace = in.readInt();
             int allowMassStorage = in.readInt();
+            long maxFileSize = in.readLong();
             return new StorageVolume(path, description,
-                    removable == 1, emulated == 1,
-                    mtpReserveSpace, storageId, allowMassStorage == 1);
+                    removable == 1, emulated == 1, mtpReserveSpace,
+                    storageId, allowMassStorage == 1, maxFileSize);
         }
 
         public StorageVolume[] newArray(int size) {
@@ -193,5 +208,6 @@
         parcel.writeInt(mStorageId);
         parcel.writeInt(mMtpReserveSpace);
         parcel.writeInt(mAllowMassStorage ? 1 : 0);
+        parcel.writeLong(mMaxFileSize);
     }
 }
diff --git a/core/res/res/values/attrs.xml b/core/res/res/values/attrs.xml
index 4bc59e4..9c2133f 100755
--- a/core/res/res/values/attrs.xml
+++ b/core/res/res/values/attrs.xml
@@ -5318,6 +5318,8 @@
         <attr name="mtpReserve" format="integer" />
         <!-- true if the storage can be shared via USB mass storage -->
         <attr name="allowMassStorage" format="boolean" />
+        <!-- maximum file size for the volume in megabytes, zero or unspecified if it is unbounded -->
+        <attr name="maxFileSize" format="integer" />
     </declare-styleable>
 
     <declare-styleable name="SwitchPreference">
diff --git a/media/java/android/mtp/MtpPropertyGroup.java b/media/java/android/mtp/MtpPropertyGroup.java
index b75b11a..76c8569 100644
--- a/media/java/android/mtp/MtpPropertyGroup.java
+++ b/media/java/android/mtp/MtpPropertyGroup.java
@@ -330,7 +330,6 @@
             }
 
             int count = (c == null ? 1 : c.getCount());
-            Log.d(TAG, "count: " + count);
             MtpPropertyList result = new MtpPropertyList(count * mProperties.length,
                     MtpConstants.RESPONSE_OK);
 
diff --git a/media/java/android/mtp/MtpStorage.java b/media/java/android/mtp/MtpStorage.java
index 7932d34..da190a6 100644
--- a/media/java/android/mtp/MtpStorage.java
+++ b/media/java/android/mtp/MtpStorage.java
@@ -32,6 +32,7 @@
     private final String mDescription;
     private final long mReserveSpace;
     private final boolean mRemovable;
+    private final long mMaxFileSize;
 
     public MtpStorage(StorageVolume volume) {
         mStorageId = volume.getStorageId();
@@ -39,6 +40,7 @@
         mDescription = volume.getDescription();
         mReserveSpace = volume.getMtpReserveSpace();
         mRemovable = volume.isRemovable();
+        mMaxFileSize = volume.getMaxFileSize();
     }
 
     /**
@@ -98,4 +100,13 @@
     public final boolean isRemovable() {
         return mRemovable;
     }
+
+   /**
+     * Returns maximum file size for the storage, or zero if it is unbounded.
+     *
+     * @return maximum file size
+     */
+    public long getMaxFileSize() {
+        return mMaxFileSize;
+    }
 }
diff --git a/media/jni/android_mtp_MtpServer.cpp b/media/jni/android_mtp_MtpServer.cpp
index aaf85c3..446b630 100644
--- a/media/jni/android_mtp_MtpServer.cpp
+++ b/media/jni/android_mtp_MtpServer.cpp
@@ -48,6 +48,7 @@
 static jfieldID field_MtpStorage_description;
 static jfieldID field_MtpStorage_reserveSpace;
 static jfieldID field_MtpStorage_removable;
+static jfieldID field_MtpStorage_maxFileSize;
 
 static Mutex sMutex;
 
@@ -228,12 +229,14 @@
         jstring description = (jstring)env->GetObjectField(jstorage, field_MtpStorage_description);
         jlong reserveSpace = env->GetLongField(jstorage, field_MtpStorage_reserveSpace);
         jboolean removable = env->GetBooleanField(jstorage, field_MtpStorage_removable);
+        jlong maxFileSize = env->GetLongField(jstorage, field_MtpStorage_maxFileSize);
 
         const char *pathStr = env->GetStringUTFChars(path, NULL);
         if (pathStr != NULL) {
             const char *descriptionStr = env->GetStringUTFChars(description, NULL);
             if (descriptionStr != NULL) {
-                MtpStorage* storage = new MtpStorage(storageID, pathStr, descriptionStr, reserveSpace, removable);
+                MtpStorage* storage = new MtpStorage(storageID, pathStr, descriptionStr,
+                        reserveSpace, removable, maxFileSize);
                 thread->addStorage(storage);
                 env->ReleaseStringUTFChars(path, pathStr);
                 env->ReleaseStringUTFChars(description, descriptionStr);
@@ -312,6 +315,11 @@
         LOGE("Can't find MtpStorage.mRemovable");
         return -1;
     }
+    field_MtpStorage_maxFileSize = env->GetFieldID(clazz, "mMaxFileSize", "J");
+    if (field_MtpStorage_maxFileSize == NULL) {
+        LOGE("Can't find MtpStorage.mMaxFileSize");
+        return -1;
+    }
     clazz_MtpStorage = (jclass)env->NewGlobalRef(clazz);
 
     clazz = env->FindClass("android/mtp/MtpServer");
diff --git a/media/mtp/MtpServer.cpp b/media/mtp/MtpServer.cpp
index bc04e8c..9085f10 100644
--- a/media/mtp/MtpServer.cpp
+++ b/media/mtp/MtpServer.cpp
@@ -871,6 +871,14 @@
     // check space first
     if (mSendObjectFileSize > storage->getFreeSpace())
         return MTP_RESPONSE_STORAGE_FULL;
+    uint64_t maxFileSize = storage->getMaxFileSize();
+    // check storage max file size
+    if (maxFileSize != 0) {
+        // if mSendObjectFileSize is 0xFFFFFFFF, then all we know is the file size
+        // is >= 0xFFFFFFFF
+        if (mSendObjectFileSize > maxFileSize || mSendObjectFileSize == 0xFFFFFFFF)
+            return MTP_RESPONSE_OBJECT_TOO_LARGE;
+    }
 
 LOGD("path: %s parent: %d storageID: %08X", (const char*)path, parent, storageID);
     MtpObjectHandle handle = mDatabase->beginSendObject((const char*)path,
diff --git a/media/mtp/MtpStorage.cpp b/media/mtp/MtpStorage.cpp
index fef8066..941e303 100644
--- a/media/mtp/MtpStorage.cpp
+++ b/media/mtp/MtpStorage.cpp
@@ -33,11 +33,13 @@
 namespace android {
 
 MtpStorage::MtpStorage(MtpStorageID id, const char* filePath,
-        const char* description, uint64_t reserveSpace, bool removable)
+        const char* description, uint64_t reserveSpace,
+        bool removable, uint64_t maxFileSize)
     :   mStorageID(id),
         mFilePath(filePath),
         mDescription(description),
         mMaxCapacity(0),
+        mMaxFileSize(maxFileSize),
         mReserveSpace(reserveSpace),
         mRemovable(removable)
 {
diff --git a/media/mtp/MtpStorage.h b/media/mtp/MtpStorage.h
index 3e4f40d..e5a2e57 100644
--- a/media/mtp/MtpStorage.h
+++ b/media/mtp/MtpStorage.h
@@ -31,6 +31,7 @@
     MtpString               mFilePath;
     MtpString               mDescription;
     uint64_t                mMaxCapacity;
+    uint64_t                mMaxFileSize;
     // amount of free space to leave unallocated
     uint64_t                mReserveSpace;
     bool                    mRemovable;
@@ -38,7 +39,7 @@
 public:
                             MtpStorage(MtpStorageID id, const char* filePath,
                                     const char* description, uint64_t reserveSpace,
-                                    bool removable);
+                                    bool removable, uint64_t maxFileSize);
     virtual                 ~MtpStorage();
 
     inline MtpStorageID     getStorageID() const { return mStorageID; }
@@ -50,6 +51,7 @@
     const char*             getDescription() const;
     inline const char*      getPath() const { return (const char *)mFilePath; }
     inline bool             isRemovable() const { return mRemovable; }
+    inline uint64_t         getMaxFileSize() const { return mMaxFileSize; }
 };
 
 }; // namespace android
diff --git a/services/java/com/android/server/MountService.java b/services/java/com/android/server/MountService.java
index 54e5432..2e54c99 100644
--- a/services/java/com/android/server/MountService.java
+++ b/services/java/com/android/server/MountService.java
@@ -1075,18 +1075,22 @@
                             com.android.internal.R.styleable.Storage_mtpReserve, 0);
                     boolean allowMassStorage = a.getBoolean(
                             com.android.internal.R.styleable.Storage_allowMassStorage, false);
+                    // resource parser does not support longs, so XML value is in megabytes
+                    long maxFileSize = a.getInt(
+                            com.android.internal.R.styleable.Storage_maxFileSize, 0) * 1024L * 1024L;
 
                     Slog.d(TAG, "got storage path: " + path + " description: " + description +
                             " primary: " + primary + " removable: " + removable +
                             " emulated: " + emulated +  " mtpReserve: " + mtpReserve +
-                            " allowMassStorage: " + allowMassStorage);
+                            " allowMassStorage: " + allowMassStorage +
+                            " maxFileSize: " + maxFileSize);
                     if (path == null || description == null) {
                         Slog.e(TAG, "path or description is null in readStorageList");
                     } else {
                         String pathString = path.toString();
                         StorageVolume volume = new StorageVolume(pathString,
                                 description.toString(), removable, emulated,
-                                mtpReserve, allowMassStorage);
+                                mtpReserve, allowMassStorage, maxFileSize);
                         if (primary) {
                             if (mPrimaryVolume == null) {
                                 mPrimaryVolume = volume;