A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statec...A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statechart diagrams, the primary system functions and corresponding traversal features are enveloped into various orthogonal regions of a composite state. The mutual relationships between orthogonal regions are implied by the orders of broadcast events. Using a modular transition system as a basic computational model, the formalization description of A-O statechart models is proposed. The precise semantics of model elements and modeling procedures is given. The example study indicates that the separation strategy of crosscutting concerns is implemented in the design phase of the concurrent software system with this method. Meanwhile, the software modeling method has advantages of loose coupling, adaptability and traceability.展开更多
Due to the absence of validity detection on pointers and automatic memory rubbish reclaim mechanisms in programming languages such as the C/C++language,software developed in these languages may have many memory safety...Due to the absence of validity detection on pointers and automatic memory rubbish reclaim mechanisms in programming languages such as the C/C++language,software developed in these languages may have many memory safety vulnerabilities,such as Use-After-Free(UAF)vulnerability.An UAF vulnerability occurs when a memory object has been freed,but it can still be accessed through a dangling pointer that points to the object before it is reclaimed.Since UAF vulnerabilities are frequently exploited by malware which may lead to memory data leakage or corruption,much research work has been carried out to detect UAF vulnerabilities.This paper investigates existing UAF detection methods.After comparing and categorizing these methods,an outlook on the future development of UAF detection methods is provided.This has an important reference value for subsequent research on UAF detection.展开更多
文摘A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statechart diagrams, the primary system functions and corresponding traversal features are enveloped into various orthogonal regions of a composite state. The mutual relationships between orthogonal regions are implied by the orders of broadcast events. Using a modular transition system as a basic computational model, the formalization description of A-O statechart models is proposed. The precise semantics of model elements and modeling procedures is given. The example study indicates that the separation strategy of crosscutting concerns is implemented in the design phase of the concurrent software system with this method. Meanwhile, the software modeling method has advantages of loose coupling, adaptability and traceability.
文摘Due to the absence of validity detection on pointers and automatic memory rubbish reclaim mechanisms in programming languages such as the C/C++language,software developed in these languages may have many memory safety vulnerabilities,such as Use-After-Free(UAF)vulnerability.An UAF vulnerability occurs when a memory object has been freed,but it can still be accessed through a dangling pointer that points to the object before it is reclaimed.Since UAF vulnerabilities are frequently exploited by malware which may lead to memory data leakage or corruption,much research work has been carried out to detect UAF vulnerabilities.This paper investigates existing UAF detection methods.After comparing and categorizing these methods,an outlook on the future development of UAF detection methods is provided.This has an important reference value for subsequent research on UAF detection.
