Method of integer overflow detection to avoid buffer overflow

A simplified integer overflow detection method based on path relaxation is described for avoiding buffer overflow triggered by integer overflow. When the integer overflow refers to the size of the buffer allocated dynamically, this kind of integer overflow is most likely to trigger buffer overflow. Based on this discovery, through lightly static program analysis, the solution traces the key variables referring to the size of a buffer allocated dynamically and it maintains the upper bound and lower bound of these variables. After the constraint information of these traced variables is inserted into the original program, this method tests the program with test cases through path relaxation, which means that it not only reports the errors revealed by the current runtime value of traced variables contained in the test case, but it also examines the errors possibly occurring under the same execution path with all the possible values of the traced variables. The effectiveness of this method is demonstrated in a case study. Compared with the traditional buffer overflow detection methods, this method reduces the burden of detection and improves efficiency.

RICB： Integer Overflow Vulnerability Dynamic Analysis via Buffer Overflow

Integer overflow vulnerability will cause buffer overflow. The research on the relationship between them will help us to detect integer overflow vulnerability. We present a dynamic analysis methods RICB （Run-time Integer Checking via Buffer overflow）. Our approach includes decompile execute file to assembly language; debug the execute file step into and step out; locate the overflow points and checking buffer overflow caused by integer overflow. We have implemented our approach in three buffer overflow types： format string overflow, stack overflow and heap overflow. Experiments results show that our approach is effective and efficient. We have detected more than 5 known integer overflow vulnerabilities via buffer overflow.

Mutation Testing for Integer Overflow in Ethereum Smart Contracts

Integer overflow is a common vulnerability in Ethereum Smart Contracts(ESCs)and often causes huge economic losses.Smart contracts cannot be changed once it is deployed on the blockchain and thus demand further testing.Mutation testing is a fault-based testing method that can effectively improve the sufficiency of a test for smart contracts.However,existing methods cannot efficiently perform mutation testing specifically for integer overflow in ESCs.Therefore,by analyzing integer overflow in ESCs,we propose five special mutation operators to address such vulnerability in terms of detecting sufficiency in ESC testing.An empirical study on 40 open-source ESCs is conducted to evaluate the effectiveness of the proposed mutation operators.Results show that(1)our proposed mutation operators can reproduce all 179 integer overflow vulnerabilities in 40 smart contracts,and the generated mutants have high compilation pass rate and integer overflow vulnerability generation rate;moreover,(2)the generated mutants can find the shortcomings of existing testing methods for integer overflow vulnerability,thereby providing effective support to improve the sufficiency of the test.