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Abstract-We present the preliminary results of our work on designing an automatic toolset for verification of Linux kernelspace drivers. By now the toolset includes three components:• a library of verification models; each model is a formal description of some safety property to be checked; • a preprocessor unit; it is intended for simulating an environment of a driver; • a verification unit BLAST; it is a general-purpose toolkit intended for automatic program verification based on Boolean abstraction and counter-example guided abstraction refinements techniques. We discuss in some details how our system operates and outline the directions for future work.Operating system (OS) is the key component of every computer system including automatic control system of power station, bank information system, or just a cheap cell phone. The faults occurred in OS may result in fatal consequences: damage of the objects under the control of computer, material losses, data leakage. For the most part program errors do not exceed the bounds of erroneous software components; they can be easily localized, checked and corrected. But if a software component operates in a kernel mode then its erroneous behaviour has far-reaching implications and tends to failure many other elements of computer system. The empirical data indicate (see [10], [21]) that bugs in kernel-space device drivers cause 85% of the system crashes. Therefore verification of OS drivers is the topical problem in software designing.The most generally employed approach to detecting bugs in application programs is testing. But in the case of OS testing encounter with a number of limitations that drastically deteriorate its effectiveness. When testing OS components one checks the correctness of their behaviour only on some specific configurations depending on the state of main and peripheral hardware, distribution of internal and external events, etc. The number of such configurations in incredibly large and even small difference in configurations may cause in significant variances in OS behaviour. That is why no reasonable test set could cover a high proportion of traces in OS code to detect all possible errors. Certainly, a highly skilled expert is able to reveal the most critical parts of OS code and thus guide the detection of errors, but in this case the reliability of a driver becomes a subject to human factor.In this paper we report on the attempts to implement a new approach to driver verification which would be able to cope pure automatically with checking the most common errors occurred in OS drivers. When verification of drivers is concerned, it should be noticed that the most important issue which need to be checked is the safety of interaction between a driver and the other components of OS. A vast amount of drivers employ only some bounded set of conventional means for interacting with the environment. Close inspection of means and templates that are used by designers of drivers makes its possible to settle in formal terms the requirements (rules) that sho...

We present the software verification tool BLAST 2.7, which we submitted for the Competition on Software Verification. The tool is an improvement over BLAST 2.5, and its development is mostly targeted at its performance and usability in the Linux Driver Verification project. The paper overviews the tool and outlines our contribution to it.

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Аннотация. Быстрый темп развития ядра и драйверов операционной системы Linux, разрабатываемых большим распределенным сообществом программистов, привел к тому, что на сегодняшний день не существует единой базы правил, которые полностью описывают корректное взаимодействие драйверов и ядра. Это является препятствием, с одной стороны, для тех программистов, которые не обладают экспертными знаниями во всех особенностях данного взаимодействия; с другой стороны, для разработки и применения инструментов, которые могли бы находить соответствующие типовые ошибки автоматизированным образом. В данной статье предлагается методика выявления и классификации типовых ошибок и соответствующих им правил на основе изменений, вносимых в драйверы операционной системы Linux. В статье приводятся результаты применения данной методики, обсуждаются полученная классификация и распределение типовых ошибок по классам. Ключевые слова: операционная система; ядро; драйвер; правило взаимодействия; классификация ошибок.

Concurrent systems work nondeterministically. For concurrent systems, UniTESK-based test suite executes methods with different parameters in different states, but it does not guarantee that all possible execution paths of a method will be tested because of its concurrent nature. This paper presents an integration method that combines the testing techniques with model checking techniques of Java PathFinder (JPF). The method guarantees that all possible execution paths needed for checking the correctness of the system are explored. The method is based on localization of the search performed by JPF. It reduces the state space while preserving the advantages of UniTESK like state abstraction and automatic checking of correctness. Moreover, it allows to use the same test suite without modification with JPF.