2015-11-06 07:50:52 +01:00
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In order to build the fuzzer one needs to build HarfBuzz and
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harfbuzz/test/fuzzing/hb-fuzzer.cc with:
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- Using the most recent Clang
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- With -fsanitize=address (or =undefined, or a combination)
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- With -fsanitize-coverage=edge[,8bit-counters,trace-cmp]
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- With various defines that limit worst case exponential behavior:
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* -DHB_MAX_NESTING_LEVEL=3
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2015-11-06 08:08:50 +01:00
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* -DHB_SANITIZE_MAX_EDITS=3
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* See Makefile.am for full list of flags
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2015-11-06 07:50:52 +01:00
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- link against libFuzzer
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To run the fuzzer one needs to first obtain a test corpus as a directory
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containing interesting fonts. A good starting point is inside
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harfbuzz/test/shaping/fonts/fonts/.
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Then, run the fuzzer like this:
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./hb-fuzzer -max_len=2048 CORPUS_DIR
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Where max_len specifies the maximal length of font files to handle.
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The smaller the faster.
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For more details consult the following locations:
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- http://llvm.org/docs/LibFuzzer.html or
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- https://github.com/google/libfuzzer-bot/tree/master/harfbuzz
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- https://github.com/behdad/harfbuzz/issues/139
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