def test_parse_log_stats(self):
"""Test pure stats parsing without applying of stat_overrides."""
log_lines = self._read_test_data('no_crash.txt')
parsed_stats = libfuzzer.parse_log_stats(log_lines)
expected_stats = {
'average_exec_per_sec': 97,
'new_units_added': 55,
'new_units_generated': 55,
'number_of_executed_units': 258724,
'peak_rss_mb': 103,
'slowest_unit_time_sec': 0
}
self.assertEqual(parsed_stats, expected_stats)
def _get_stats_from_log(log_path,
strategies=None,
arguments=None,
stats_overrides=None):
"""Calculate stats for the given log the same way as the engine does."""
if strategies is None:
strategies = []
if arguments is None:
arguments = []
log_lines = utils.decode_to_unicode(
utils.read_data_from_file(log_path, eval_data=False)).splitlines()
stats = libfuzzer.parse_log_stats(log_lines)
stats.update(
performance_stats.parse_performance_features(log_lines, strategies,
arguments))
if stats_overrides:
stats.update(stats_overrides)
return stats
def fuzz(self, target_path, options, reproducers_dir, max_time):
"""Run a fuzz session.
Args:
target_path: Path to the target.
options: The FuzzOptions object returned by prepare().
reproducers_dir: The directory to put reproducers in when crashes
are found.
max_time: Maximum allowed time for the fuzzing to run.
Returns:
A FuzzResult object.
"""
profiler.start_if_needed('libfuzzer_fuzz')
runner = libfuzzer.get_runner(target_path)
libfuzzer.set_sanitizer_options(target_path, fuzz_options=options)
# Directory to place new units.
if options.merge_back_new_testcases:
new_corpus_dir = self._create_temp_corpus_dir('new')
corpus_directories = [new_corpus_dir] + options.fuzz_corpus_dirs
else:
corpus_directories = options.fuzz_corpus_dirs
fuzz_result = runner.fuzz(corpus_directories,
fuzz_timeout=max_time,
additional_args=options.arguments,
artifact_prefix=reproducers_dir,
extra_env=options.extra_env)
project_qualified_fuzzer_name = (
engine_common.get_project_qualified_fuzzer_name(target_path))
dict_error_match = DICT_PARSING_FAILED_REGEX.search(fuzz_result.output)
if dict_error_match:
logs.log_error(
'Dictionary parsing failed '
f'(target={project_qualified_fuzzer_name}, '
f'line={dict_error_match.group(1)}).',
engine_output=fuzz_result.output)
elif (not environment.get_value('USE_MINIJAIL') and
fuzz_result.return_code == constants.LIBFUZZER_ERROR_EXITCODE):
# Minijail returns 1 if the exit code is nonzero.
# Otherwise: we can assume that a return code of 1 means that libFuzzer
# itself ran into an error.
logs.log_error(ENGINE_ERROR_MESSAGE +
f' (target={project_qualified_fuzzer_name}).',
engine_output=fuzz_result.output)
log_lines = fuzz_result.output.splitlines()
# Output can be large, so save some memory by removing reference to the
# original output which is no longer needed.
fuzz_result.output = None
# Check if we crashed, and get the crash testcase path.
crash_testcase_file_path = runner.get_testcase_path(log_lines)
# If we exited with a non-zero return code with no crash file in output from
# libFuzzer, this is most likely a startup crash. Use an empty testcase to
# to store it as a crash.
if (not crash_testcase_file_path and fuzz_result.return_code
not in constants.NONCRASH_RETURN_CODES):
crash_testcase_file_path = self._create_empty_testcase_file(
reproducers_dir)
# Parse stats information based on libFuzzer output.
parsed_stats = libfuzzer.parse_log_stats(log_lines)
# Extend parsed stats by additional performance features.
parsed_stats.update(
stats.parse_performance_features(log_lines, options.strategies,
options.arguments))
# Set some initial stat overrides.
timeout_limit = fuzzer_utils.extract_argument(options.arguments,
constants.TIMEOUT_FLAG,
remove=False)
actual_duration = int(fuzz_result.time_executed)
fuzzing_time_percent = 100 * actual_duration / float(max_time)
parsed_stats.update({
'timeout_limit': int(timeout_limit),
'expected_duration': int(max_time),
'actual_duration': actual_duration,
'fuzzing_time_percent': fuzzing_time_percent,
})
# Remove fuzzing arguments before merge and dictionary analysis step.
non_fuzz_arguments = options.arguments.copy()
libfuzzer.remove_fuzzing_arguments(non_fuzz_arguments, is_merge=True)
if options.merge_back_new_testcases:
self._merge_new_units(target_path, options.corpus_dir,
new_corpus_dir, options.fuzz_corpus_dirs,
non_fuzz_arguments, parsed_stats)
fuzz_logs = '\n'.join(log_lines)
crashes = []
if crash_testcase_file_path:
reproduce_arguments = options.arguments[:]
libfuzzer.remove_fuzzing_arguments(reproduce_arguments)
# Use higher timeout for reproduction.
libfuzzer.fix_timeout_argument_for_reproduction(
reproduce_arguments)
# Write the new testcase.
# Copy crash testcase contents into the main testcase path.
crashes.append(
engine.Crash(crash_testcase_file_path, fuzz_logs,
reproduce_arguments, actual_duration))
if options.analyze_dictionary:
libfuzzer.analyze_and_update_recommended_dictionary(
runner, project_qualified_fuzzer_name, log_lines,
options.corpus_dir, non_fuzz_arguments)
return engine.FuzzResult(fuzz_logs, fuzz_result.command, crashes,
parsed_stats, fuzz_result.time_executed)
def test_parse_log_and_stats_from_corrupted_output(self):
"""Test stats parsing from a log with corrupted libFuzzer stats."""
log_lines = self._read_test_data('corrupted_stats.txt')
parsed_stats = libfuzzer.parse_log_stats(log_lines)
self.assertNotIn('peak_rss_mb', parsed_stats)