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Diffstat (limited to 'llvm/docs/LibFuzzer.rst')
| -rw-r--r-- | llvm/docs/LibFuzzer.rst | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/llvm/docs/LibFuzzer.rst b/llvm/docs/LibFuzzer.rst index 1ac75a40698..3b074aad6a1 100644 --- a/llvm/docs/LibFuzzer.rst +++ b/llvm/docs/LibFuzzer.rst @@ -68,6 +68,8 @@ The most important flags are:: apply_tokens 0 Read the given input file, substitute bytes with tokens and write the result to stdout. sync_command 0 Execute an external command "<sync_command> <test_corpus>" to synchronize the test corpus. sync_timeout 600 Minimum timeout between syncs. + use_traces 0 Experimental: use instruction traces + For the full list of flags run the fuzzer binary with ``-help=1``. @@ -273,6 +275,18 @@ The fuzzer itself will still be mutating a string of bytes but before passing this input to the target library it will replace every byte ``b`` with the ``b``-th token. If there are less than ``b`` tokens, a space will be added instead. +Data-flow-guided fuzzing +------------------------ + +*EXPERIMENTAL*. +With an additional compiler flag ``-fsanitize-coverage=trace-cmp`` (see SanitizerCoverageTraceDataFlow_) +and extra run-time flag ``-use_traces=1`` the fuzzer will try to apply *data-flow-guided fuzzing*. +That is, the fuzzer will record the inputs to comparison instructions, switch statements, +and several libc functions (``memcmp``, ``strncmp``, etc). +It will later use those recorded inputs during mutations. + +This mode can be combined with DataFlowSanitizer_ to achieve better sensitivity. + AFL compatibility ----------------- LibFuzzer can be used in parallel with AFL_ on the same test corpus. @@ -412,6 +426,8 @@ Examples: regular expression matchers, text or binary format parsers. .. _AFL: http://lcamtuf.coredump.cx/afl/ .. _SanitizerCoverage: http://clang.llvm.org/docs/SanitizerCoverage.html +.. _SanitizerCoverageTraceDataFlow: http://clang.llvm.org/docs/SanitizerCoverage.html#tracing-data-flow +.. _DataFlowSanitizer: http://clang.llvm.org/docs/DataFlowSanitizer.html .. _Heartbleed: http://en.wikipedia.org/wiki/Heartbleed |
