android13/hardware/interfaces/bluetooth/1.0/default/test/fuzzer

Fuzzer for android.hardware.bluetooth@1.0-impl-test

Plugin Design Considerations

The fuzzer plugin for android.hardware.bluetooth@1.0-impl-test is designed based on the understanding of the source code and tries to achieve the following:

Maximize code coverage

1. The configuration parameters are not hardcoded, but instead selected based on incoming data. This ensures more code paths are reached by the fuzzer.

2. A new library 'libbt-vendor-fuzz.so' is created that implements functions of bt_vendor_interface_t and calls them in order to maximize the code coverage

android.hardware.bluetooth@1.0-impl-test supports the following parameters:

1. Bluetooth Address (parameter name: btAddress)

Parameter	Valid Values	Configured Value
btAddress	Values inside array ranges from 0x0 to 0xFF	Value obtained from FuzzedDataProvider

This also ensures that the plugin is always deterministic for any given input.

Maximize utilization of input data

The plugin feeds the entire input data to the module. This ensures that the plugin tolerates any kind of input (empty, huge, malformed, etc) and doesnt exit() on any input and thereby increasing the chance of identifying vulnerabilities.

Build

This describes steps to build bluetoothV1.0_fuzzer binary.

Android

Steps to build

Build the fuzzer

  $ mm -j$(nproc) bluetoothV1.0_fuzzer

Steps to run

To run on device

  $ adb sync data
  $ adb shell LD_LIBRARY_PATH=/data/fuzz/${TARGET_ARCH}/lib/ /data/fuzz/${TARGET_ARCH}/bluetoothV1.0_fuzzer/bluetoothV1.0_fuzzer

References:

• http://llvm.org/docs/LibFuzzer.html
• https://github.com/google/oss-fuzz