43 lines
2.2 KiB
Plaintext
43 lines
2.2 KiB
Plaintext
This directory contains tests to be run with clang's libFuzzer. It will generate data, pass this
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data to the function
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LLVMFuzzerTestOneInput(const char *Data, size_t Size)
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of the test and track the code execution. Should the test crash, libFuzzer will provide you with the
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data which triggered the crash. You can then use this to debug and fix the called code.
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! Please note: The purpose of fuzz testing is to find unexpected code paths. Running fuzz tests may!
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! result in unforeseen behavior, including loss of data. Consider running the tests in an isolated !
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! environment, e.g. on a virtual machine. You have been warned. !
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To run a test with libFuzzer:
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1. Install clang 5.0 or later, e.g. from the repositories of the Linux distribution you are using.
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Depending on the version of clang and the source you are installing from, you might have to
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install libFuzzer for this version of clang explicitly.
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2. Make sure clang and clang++ from this version of clang are found in PATH.
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3. Configure Qt with
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-platform linux-clang -sanitize fuzzer-no-link
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or, if you are using clang 5
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-platform linux-clang -coverage trace-pc-guard
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to add the needed code coverage instrumentation. Since speed of execution is crucial for fuzz
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testing, it's recommendable to also use the switches
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-release -static
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It might also make sense to add sanitizers by passing
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-sanitize <...>
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4. Build Qt.
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5. Build one of the tests using this Qt build.
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6. Execute the resulting executable.
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Depending on the expected input format of the tested function, you will get results faster if
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you:
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* provide a set of interesting input data by passing the path of a directory which contains
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these data, each in one file. You can find such data sets in the subdirectory
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"fuzzing/testcases" of the qtqa repository.
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* pass a so-called dictionary listing keywords of the input format using
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-dict=<dictionary file>
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A couple of such dictionaries are provided by AFL (http://lcamtuf.coredump.cx/afl/)
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* tell libFuzzer to generate only ASCII data using
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-only_ascii=1
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For further info, see https://llvm.org/docs/LibFuzzer.html
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