Keeping privacy data secure under factory recovery

Nowadays, mobile devices are widely used. Mobile smartphones are not only a carrier for users to record, store, or transfer sensitive data in social network, but also a covert forensic tool for some security departments. In some extreme cases like war correspondent being about to be captured, the operation records of shooting and communication on the mobile phone will bring them disadvantages. Immediately performing a factory recovery is the smartest option. However, this operation will clear all user data, including those important case scene evidence. This paper proposes a flexible and reliable factory recovery mechanism to protect sensitive data under factory recovery. By analyzing the factory recovery process and mastering the Linux kernel execution process, to ensure that when users perform factory recovery operations, applications and data can be cleared normally, and the private data that users want to keep is protected. We evaluated the safety and usability of the method.