CPU flush instruction-based cache side-channel attacks (cache instruction attacks) target a wide range of machines. For instance, Meltdown / Spectre combined with FLUSH+RELOAD gain read access to arbitrary data in operating system kernel and user processes, which work on cloud virtual machines, laptops, desktops, and mobile devices. Additionally, fault injection attacks use a CPU cache. For instance, Rowhammer, is a cache instruction attack that attempts to obtain write access to arbitrary data in physical memory, and affects machines that have DDR3. To protect against existing cache instruction attacks, various existing mechanisms have been proposed to modify hardware and software aspects; however, when latest cache instruction attacks are disclosed, these mechanisms cannot prevent these. Moreover, additional countermeasure requires long time for the designing and developing process. This paper proposes a novel mechanism termed FlushBlocker to protect against all types of cache instruction attacks and mitigate against cache instruction attacks employ latest side-channel vulnerability until the releasing of additional countermeasures. FlushBlocker employs an approach that restricts the issuing of cache flush instructions and the attacks that lead to failure by limiting control of the CPU cache. To demonstrate the effectiveness of this study, FlushBlocker was implemented in the latest Linux kernel, and its security and performance were evaluated. Results show that FlushBlocker successfully prevents existing cache instruction attacks (e.g., Meltdown, Spectre, and Rowhammer), the performance overhead was zero, and it was transparent in real-world applications.

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Multicore processors are widely used for various types of computers. In order to achieve high-performance on such multicore systems, it is necessary to extract coarse grain task parallelism from a target program in addition to loop parallelism. Regarding the development of parallel programs, Java or a Java-extension language represents an attractive choice recently, thanks to its performance improvement as well as its platform independence. Therefore, this paper proposes a parallel Java code generation scheme that realizes coarse grain task parallel processing with layer-unified execution control. In this parallel processing, coarse grain tasks of all layers are collectively managed through a dynamic scheduler. In addition, we have developed a prototype parallelizing compiler for Java programs with directives. In performance evaluations, the compiler-generated parallel Java code was confirmed to attain high performance. Concretely, we obtained 7.82 times faster speed-up for the Jacobi program, 7.38 times faster speed-up for the Turb3d program, 6.54 times faster speed-up for the Crypt program, and 6.15 times faster speed-up for the MolDyn program on eight cores of Xeon E5-2660.

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Multicore processors are widely used for various types of computers. In order to achieve high-performance on such multicore systems, it is necessary to extract coarse grain task parallelism from a target program in addition to loop parallelism. Regarding the development of parallel programs, Java or a Java-extension language represents an attractive choice recently, thanks to its performance improvement as well as its platform independence. Therefore, this paper proposes a parallel Java code generation scheme that realizes coarse grain task parallel processing with layer-unified execution control. In this parallel processing, coarse grain tasks of all layers are collectively managed through a dynamic scheduler. In addition, we have developed a prototype parallelizing compiler for Java programs with directives. In performance evaluations, the compiler-generated parallel Java code was confirmed to attain high performance. Concretely, we obtained 7.82 times faster speed-up for the Jacobi program, 7.38 times faster speed-up for the Turb3d program, 6.54 times faster speed-up for the Crypt program, and 6.15 times faster speed-up for the MolDyn program on eight cores of Xeon E5-2660.

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Understanding how application programming interfaces (APIs) are used in a program plays an important role in malware analysis. This, however, has resulted in an endless battle between malware authors and malware analysts around the development of API [de]obfuscation techniques over the last few decades. Our goal in this paper is to show the limit of existing API de-obfuscation techniques. To do that, we first analyzed existing API [de]obfuscation techniques and clarified that an attack vector commonly exists in these techniques; then, we present Stealth Loader, which is a program loader to bypass all existing API de-obfuscation techniques. The core idea of Stealth Loader is to load a dynamic link library (DLL) and resolve its dependency without leaving any traces on memory to be detected. We demonstrated the effectiveness of Stealth Loader by analyzing a set of Windows executables and malware protected with Stealth Loader using major dynamic and static analysis tools. The results indicate that among other obfuscation tools, only Stealth Loader is able to successfully bypass all analysis tools.

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This article is a summary of basic system administration for configuring client-server computers connected to the Internet. Thisarticle assumes that the reader has some basic knowledge of the UNIX operating system. The goal of this summary is to provideresearchers in the academic and corporate research environments a short handbook, which will allow them to maintain a basic network ofworkstations, minimize disk utilization, optimize network cpu performance, and to better disseminate information to other researchers.This also describes the procedures to install most free software, including X-windows, FTP and HTTP information servers and Mosaicclients. The document focuses specifically on the Sparc/SunOS based platforms, but should be useful in administering other types ofworkstations. This handbook is not designed to replace the many volume sets of documentation provided by vendors, but rather, it listshelpful tips that may be scattered throughout the documentation. The main goal of providing these system administration procedures isto encourage better networking in the research environment. By following the steps in this handbook, a research group should be able toinstall many of the network servers to provide freer access to information at their site. This information can be beneficial to the otherresearchers at the local site or to the rest of the computing public. This handbook describes how to install and use the Mosaic Internetbrowser. As a tutorial, users will be shown how to read this document on-line with Mosaic. Lastly, this article announces thebeginning of on-line articles for Thermal Science and Engineering which is a Journal of the Heat Transfer Society of Japan.

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