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In this paper, we propose a dynamic analysis technique that diagnoses various kinds of deadlocks of embedded devices by OS-level analysis. Especially, we focus on minimizing performance overhead while inspecting deadlocks, because embedded applications run with limited system resources. Our experimental results show that our scheme detects all deadlocks which are induced in our test cases and incurs reasonable performance overhead (up to 16%), compared with the conventional scheme.

In this paper, we revisit the traditional memory debugging approach for CE Devices, and propose a novel memory debugging platform by modifying both DUMA library and Zram. Especially, we focus on the memory space wasted while detecting the memory error, because most CE devices have limited memory resource. For evaluation, we implemented a prototype of our debugging platform on Linux kernel version 4.8.17 and conducted various experiments with two different workloads. Our experimental results show that our scheme improves the performance of swapping by up to 58 times.

Recently, IoT (Internet of Things) environment centered Smart TV has been developed exponentially to provide a convenient and connected life experience to users. But this environment is vulnerable to a hacking attempt, as each of the devices is exposed to a hacker. To achieve ideal balance between security and convenience, this paper proposes an implicit authentication method based on users' TV viewing history. This machine learning model is trained on the server with face set, and it is operated on the client TV after deployment. When compared to previous authentication methods, our model has an advantage in user convenience and it is highly impenetrable in terms of security as it updates the model regularly.

Due to rapid advancement of technology, embedded devices are evolving quickly and closing the gap between virtual and real work. Embedded devices should be able to use services and data offered by other embedded devices efficiently. This requires an efficient and scalable inter device communication framework which can be used to provide Internet of Things (IOT) ecosystem as well. In this paper we are proposing an efficient device to device communication framework by extending the DBus and KDBus Remote Procedure Call (RPC) mechanism. The proposed framework consists of two RPC interfaces: one is in user space for control and the other is in kernel space for data transport. User space RPC interface authenticates devices and gathers services information using DBus introspection feature to share it with other embedded devices. Kernel level RPC interface will be responsible for transferring and receiving payload with other embedded devices. Kernel RPC interface will use kernel socket to achieve better data throughput.

In the embedded system, the memory profiling of an application is very critical and important to solve the problem. The memory usage is usually measured on the basis of process-level granularity. However, the process-level memory usage gives a lack of information to analyze an application, which consists of big processes with many threads. If a specific thread in the process has memory problems like memory leak or large memory consumption, then this may lead to a malfunction of an application due to the waste of an unnecessary memory by the problematic thread. This paper gives an efficient framework to get a memory usage of a process with thread level granularity and we called it Memory Usage Per Thread (MUPT). This framework would provide memory allocation information in terms of page_fault for a given multi-threaded process with thread granularity and results are expressed using new added proc interface. Thus, MUPT provides a mechanism to debug or monitor the thread memory usage and guide an application user to detect memory leak or large amount of incorrect memory allocation.

C/C++ programs often suffer from memory corruption bugs. Over the years, numerous tools were developed to help with their detection. A recent addition is AddressSanitizer (ASan) an extraordinarily fast runtime checker with a good coverage of various types of bugs. This paper describes our experience in integration of ASan technology into large-scale software products: Tizen distribution and Linux kernel. The tool has already found around a hundred of serious memory bugs in various Tizen applications and in mainline Linux kernel.

Memory compaction enables allocating a physically contiguous memory by rearranging the memory that is managed by the operating system. It is especially useful feature on the CE device because memory compaction enables some dedicated memory region to be used with other purposes. However, it takes a long time to rearrange the memory. This paper proposes the method for reducing rearrange time by partitioning the allocation region. Furthermore, this paper shows performance improvement by 30.8 times on a real environment.

The Network File System (NFS) is one of the most popular remote file system protocols for accessing directories and files over the network. If NFS mount point has thousands of files (e.g. a directory containing 5000 files), there is a significant performance drop in directory browsing (traverse, open(), stat() and read()) time as compared to local file system browsing (traverse, open(), stat() and read()) time. In order to reduce the file browsing time in the NFS with single client system, this paper presents the modification of a conventional NFS protocol usage with multiple client systems. Experimental results show the proposed implementation gives 44.6% performance improvement over a conventional one.

Restricting vulnerable process and its file I/O behaviors is important for securing an embedded device against intrusions, malware infection and information leakage. On embedded device like Smart TV, user can connect to internet using Web Browser process and can download many applications and games. These applications or games may have viruses or vulnerable code. If attacker with root privilege is able to launch new process (using fork () in Linux system) then the downloaded virus program will also get root privileges and hence vulnerable application with root user privileges may corrupt the whole system. This paper proposes a new method to protect the system from this kind of security threats. For experiment and result verification, proposed method uses LSM framework and TOMOYO module. It implements the LSM hook in fork/exec system call path to control the privileges of vulnerable application/binary. Android addresses this problem by writing a wrapper to fork system call in their framework, which modifies credential of new process. However they leave security hole, if application directly calls fork () system call.