Code: status_t BnGraphicBufferConsumer::onTransact(
 uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
{
 switch(code) {
 case ACQUIRE_BUFFER: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 BufferItem item;
 int64_t presentWhen = data.readInt64();
 status_t result = acquireBuffer(&item, presentWhen);
 status_t err = reply->write(item);
 if (err) return err;
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case DETACH_BUFFER: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 int slot = data.readInt32();
 int result = detachBuffer(slot);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case ATTACH_BUFFER: {

             CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
             sp<GraphicBuffer> buffer = new GraphicBuffer();
             data.read(*buffer.get());
            int slot;
             int result = attachBuffer(&slot, buffer);
             reply->writeInt32(slot);
             reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case RELEASE_BUFFER: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 int buf = data.readInt32();
 uint64_t frameNumber = data.readInt64();
            sp<Fence> releaseFence = new Fence();
 status_t err = data.read(*releaseFence);
 if (err) return err;
 status_t result = releaseBuffer(buf, frameNumber,
                    EGL_NO_DISPLAY, EGL_NO_SYNC_KHR, releaseFence);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case CONSUMER_CONNECT: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
            sp<IConsumerListener> consumer = IConsumerListener::asInterface( data.readStrongBinder() );
 bool controlledByApp = data.readInt32();
 status_t result = consumerConnect(consumer, controlledByApp);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case CONSUMER_DISCONNECT: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 status_t result = consumerDisconnect();
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case GET_RELEASED_BUFFERS: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint64_t slotMask;
 status_t result = getReleasedBuffers(&slotMask);
            reply->writeInt64(slotMask);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case SET_DEFAULT_BUFFER_SIZE: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint32_t w = data.readInt32();
 uint32_t h = data.readInt32();
 status_t result = setDefaultBufferSize(w, h);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case SET_DEFAULT_MAX_BUFFER_COUNT: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint32_t bufferCount = data.readInt32();
 status_t result = setDefaultMaxBufferCount(bufferCount);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case DISABLE_ASYNC_BUFFER: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 status_t result = disableAsyncBuffer();
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case SET_MAX_ACQUIRED_BUFFER_COUNT: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint32_t maxAcquiredBuffers = data.readInt32();
 status_t result = setMaxAcquiredBufferCount(maxAcquiredBuffers);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case SET_CONSUMER_NAME: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
            setConsumerName( data.readString8() );
 return NO_ERROR;
 } break;
 case SET_DEFAULT_BUFFER_FORMAT: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint32_t defaultFormat = data.readInt32();
 status_t result = setDefaultBufferFormat(defaultFormat);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case SET_CONSUMER_USAGE_BITS: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint32_t usage = data.readInt32();
 status_t result = setConsumerUsageBits(usage);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case SET_TRANSFORM_HINT: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 uint32_t hint = data.readInt32();
 status_t result = setTransformHint(hint);
            reply->writeInt32(result);
 return NO_ERROR;
 } break;
 case DUMP: {
            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
 String8 result = data.readString8();
 String8 prefix = data.readString8();
 static_cast<IGraphicBufferConsumer*>(this)->dump(result, prefix);
            reply->writeString8(result);
 return NO_ERROR;
 }
 }
 return BBinder::onTransact(code, data, reply, flags);
}

Vulnerability Type: Bypass +Info 
CWE ID: CWE-254
Summary: The BnGraphicBufferConsumer::onTransact function in libs/gui/IGraphicBufferConsumer.cpp in mediaserver in Android 5.x before 5.1.1 LMY49H and 6.x before 2016-03-01 does not initialize a certain slot variable, which allows attackers to obtain sensitive information, and consequently bypass an unspecified protection mechanism, by triggering an ATTACH_BUFFER action, as demonstrated by obtaining Signature or SignatureOrSystem access, aka internal bug 26338113.
Commit Message: IGraphicBufferConsumer: fix ATTACH_BUFFER info leak

Bug: 26338113
Change-Id: I019c4df2c6adbc944122df96968ddd11a02ebe33
