Dynamic Detection of Use-After-Free Bugs

Resumo

A novel method for detecting use-after-free bugs based on the program dynamic analysis is described. In memory unsafe programming languages, such as C or C++, this class of bugs mainly occurs when the program tries to access an area of dynamically allocated memory that has been already freed. For each program execution path, the method checks the correction of the allocation, deallocation, and access operations. Since the dynamic analysis is used, bugs can be found only in the parts of the code that was actually executed. The symbolic program execution with the help of SMT (Satisfiability Modulo Theories) solvers is used. This allows us to generate data the processing of which produces new execution paths.