fix(mutation): ensure maxSize >= size when using libfuzzer #952
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fmeum
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...in/java/com/code_intelligence/jazzer/mutation/mutator/libfuzzer/LibFuzzerMutatorFactory.java
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…sive Since users are free to change fuzz test signature, readExclusive might return byte arrays longer than maxLength. Calling libfuzzer's Mutate with maxSize that is less than the length of the array to be mutated might result in a segfault at the time when the data type is used in Java. Some of libfuzzer's mutators (Mutate_AddWordFromTORC) are not designed to handle this case and will mutate past the array bounds. Co-authored-by: Simon Resch <simon.resch@code-intelligence.com>
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Since users are free to change fuzz test signature, readExclusive might return byte arrays longer than maxLength. Calling libfuzzer's Mutate with maxSize that is less than the length of the array to be mutated might result in a segfault at the time when the data type is used in Java. Some of libfuzzer's mutators (Mutate_AddWordFromTORC) are not designed to handle this case and will mutate past the array bounds.