High level conclusions

Fuzzer fuzz_rst_parse is blocked:

The runtime code coverage of fuzz_rst_parse covers 16.27% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzer fuzz_rst is blocked:

The runtime code coverage of fuzz_rst covers 20.96% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Reachability and coverage overview

Functions statically reachable by fuzzers

58 / 2270

Cyclomatic complexity statically reachable by fuzzers

204 / 7678

Runtime code coverage of functions

382 / 2270

Warning: The number of runtime covered functions are larger than the number of reachable functions. This means that Fuzz Introspector found there are more functions covered at runtime than what is considered reachable based on the static analysis. This is a limitation in the analysis as anything covered at runtime is by definition reachable by the fuzzers.
This is likely due to a limitation in the static analysis. In this case, the count of functions covered at runtime is the true value, which means this is what should be considered "achieved" by the fuzzer.

Use the project functions table below to query all functions that were not covered at runtime.

The following table shows data about each function in the project. The functions included in this table correspond to all functions that exist in the executables of the fuzzers. As such, there may be functions that are from third-party libraries.

For further technical details on the meaning of columns in the below table, please see the Glossary .

Func name	Functions filename	Args	Function call depth	Reached by Fuzzers	Runtime reached by Fuzzers	Combined reached by Fuzzers	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

Fuzzer: fuzz_rst

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	126	62.6%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	75	37.3%
All colors	201	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
60	30	docutils.utils.DependencyList.__init__	call site: 00030	docutils.frontend.OptionParser.get_config_file_settings
31	169	docutils.nodes.Element.starttag	call site: 00169	docutils.nodes.pending.pformat
13	142	...fuzz_rst.TestOneInput	call site: 00142	docutils.nodes.Element.pformat
4	19	docutils.frontend.OptionParser.__init__	call site: 00019	docutils.frontend.OptionParser.get_standard_config_settings
3	99	...fuzz_rst.TestOneInput	call site: 00099	warnings.catch_warnings
3	108	docutils.utils.Reporter.__init__	call site: 00108	.isinstance
3	136	docutils.parsers.rst.Parser.parse	call site: 00136	fdp.ConsumeBool
2	161	docutils.nodes.Element.starttag	call site: 00161	.int
1	8	docutils.frontend.OptionParser.__init__	call site: 00008	optparse.TitledHelpFormatter
1	17	docutils.frontend.OptionParser.populate_from_components	call site: 00017	optparse.OptionParser.defaults.update
1	28	docutils.utils.DependencyList.__init__	call site: 00028	.open
1	96	...fuzz_rst.TestOneInput	call site: 00096	fdp.ConsumeIntInRange

Runtime coverage analysis

Covered functions

415

Functions that are reachable but not covered

98

Reachable functions

124

Percentage of reachable functions covered

20.97%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_rst	17
docutils.frontend	58
docutils.utils	13
docutils.io	3
docutils.nodes	35
docutils.parsers.rst	4
docutils.statemachine	5
docutils.writers.odf_odt	4

Fuzzer: fuzz_rst_parse

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	73	59.3%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	50	40.6%
All colors	123	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
60	34	docutils.utils.DependencyList.__init__	call site: 00034	docutils.frontend.OptionParser.get_config_file_settings
4	23	docutils.frontend.OptionParser.__init__	call site: 00023	docutils.frontend.OptionParser.get_standard_config_settings
3	102	docutils.utils.Reporter.__init__	call site: 00102	.isinstance
2	118	docutils.nodes.document.note_source	call site: 00118	docutils.frontend.get_default_settings
1	6	...fuzz_rst_parse.TestOneInput	call site: 00006	docutils.frontend.get_default_settings
1	12	docutils.frontend.OptionParser.__init__	call site: 00012	optparse.TitledHelpFormatter
1	21	docutils.frontend.OptionParser.populate_from_components	call site: 00021	optparse.OptionParser.defaults.update
1	32	docutils.utils.DependencyList.__init__	call site: 00032	.open

Runtime coverage analysis

Covered functions

416

Functions that are reachable but not covered

72

Reachable functions

86

Percentage of reachable functions covered

16.28%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_rst_parse	6
docutils.parsers	3
docutils.utils	13
docutils.frontend	57
docutils.io	3
docutils.nodes	10

Fuzzer: fuzz_table

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is

Color	Runtime hitcount	Callsite count	Percentage
red	0	5	10.2%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	44	89.7%
All colors	49	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
2	8	docutils.statemachine.ViewList.__init__	call site: 00008	docutils.statemachine.string2lines
1	1	...fuzz_table.TestOneInput	call site: 00001	docutils.statemachine.ViewList.__init__
1	13	docutils.statemachine.string2lines	call site: 00013	.len
1	21	docutils.parsers.rst.tableparser.TableParser.find_head_body_sep	call site: 00021	line.replace

Runtime coverage analysis

Covered functions

416

Functions that are reachable but not covered

18

Reachable functions

31

Percentage of reachable functions covered

41.94%

NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
/	1
...fuzz_table	8
docutils.statemachine	7
docutils.parsers.rst.tableparser	18

Optimal target analysis

Remaining optimal interesting functions

The following table shows a list of functions that are optimal targets. Optimal targets are identified by finding the functions that in combination, yield a high code coverage.

Func name	Functions filename	Arg count	Args	Function depth	hitcount	instr count	bb count	cyclomatic complexity	Reachable functions	Incoming references	total cyclomatic complexity	Unreached complexity
docutils.writers._html_base.HTMLTranslator.visit_math	docutils.writers._html_base	2	['N/A', 'N/A']	5	0	5	15	9	111	1	395	359
docutils.writers.odf_odt.Writer.assemble_my_parts	docutils.writers.odf_odt	1	['N/A']	4	0	13	7	6	82	1	269	254
docutils.parsers.rst.directives.misc.Include.run	docutils.parsers.rst.directives.misc	1	['N/A']	6	0	2	5	5	154	0	503	204
docutils.utils.math.math2html.Formula.parse	docutils.utils.math.math2html	2	['N/A', 'N/A']	8	0	7	4	5	66	0	210	186
docutils.transforms.universal.SmartQuotes.apply	docutils.transforms.universal	1	['N/A']	3	0	3	7	6	48	0	160	139
docutils.writers._html_base.HTMLTranslator.visit_image	docutils.writers._html_base	2	['N/A', 'N/A']	5	0	5	11	7	79	0	257	136
docutils.core.Publisher.publish	docutils.core	8	['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A']	7	0	11	5	5	134	25	443	131

Implementing fuzzers that target the above functions will improve reachability such that it becomes:

Functions statically reachable by fuzzers

235 / 2270

Cyclomatic complexity statically reachable by fuzzers

884 / 7678

All functions overview

If you implement fuzzers for these functions, the status of all functions in the project will be:

Func name	Functions filename	Args	Function call depth	Reached by Fuzzers	Runtime reached by Fuzzers	Combined reached by Fuzzers	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

This sections provides heuristics that can be used as input to a fuzz engine when running a given fuzz target. The current focus is on providing input that is usable by libFuzzer.

/src/fuzz_rst.py

Dictionary

Use this with the libFuzzer -dict=DICT.file flag

Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name

-focus_function=['docutils.utils.DependencyList.__init__', 'docutils.nodes.Element.starttag', '...fuzz_rst.TestOneInput', 'docutils.frontend.OptionParser.__init__', 'docutils.utils.Reporter.__init__', 'docutils.parsers.rst.Parser.parse', 'docutils.frontend.OptionParser.populate_from_components']

/src/fuzz_rst_parse.py

Dictionary

Use this with the libFuzzer -dict=DICT.file flag

Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name

-focus_function=['docutils.utils.DependencyList.__init__', 'docutils.frontend.OptionParser.__init__', 'docutils.utils.Reporter.__init__', 'docutils.nodes.document.note_source', '...fuzz_rst_parse.TestOneInput', 'docutils.frontend.OptionParser.populate_from_components']

/src/fuzz_table.py

Dictionary

Use this with the libFuzzer -dict=DICT.file flag

Fuzzer function priority

Use one of these functions as input to libfuzzer with flag: -focus_function name

-focus_function=['docutils.statemachine.ViewList.__init__', '...fuzz_table.TestOneInput', 'docutils.statemachine.string2lines', 'docutils.parsers.rst.tableparser.TableParser.find_head_body_sep']

This section shows analysis of runtime coverage data.

For futher technical details on how this section is generated, please see the Glossary .

Complex functions with low coverage

Func name	Function total lines	Lines covered at runtime	percentage covered	Reached by fuzzers
docutils.io.Input.decode	31	4	12.90%	['fuzz_table', 'fuzz_rst_parse', 'fuzz_rst']
docutils.parsers.rst.tableparser.GridTableParser.structure_from_cells	32	4	12.5%	['fuzz_table', 'fuzz_rst_parse', 'fuzz_rst']
docutils.utils.smartquotes.educate_tokens	64	0	0.0%	[]
docutils.utils.smartquotes.tokenize	57	1	1.754%	['fuzz_table', 'fuzz_rst_parse', 'fuzz_rst']
docutils.transforms.universal.SmartQuotes.apply	37	3	8.108%	['fuzz_table', 'fuzz_rst_parse', 'fuzz_rst']
docutils.parsers.rst.states.Body.isolate_grid_table	32	0	0.0%	[]
docutils.parsers.rst.states.Body.substitution_def	50	0	0.0%	[]
docutils.parsers.rst.states.Body.parse_directive_block	34	0	0.0%	[]
table.update	32	15	46.87%	['fuzz_table', 'fuzz_rst_parse', 'fuzz_rst']

This section shows which files and directories are considered in this report. The main reason for showing this is fuzz introspector may include more code in the reasoning than is desired. This section helps identify if too many files/directories are included, e.g. third party code, which may be irrelevant for the threat model. In the event too much is included, fuzz introspector supports a configuration file that can exclude data from the report. See the following link for more information on how to create a config file: link

Files in report

Source file	Reached by	Covered by
	[]	[]
Image	[]	[]
docutils.utils.smartquotes	[]	[]
docutils.parsers.docutils_xml	[]	[]
...fuzz_rst	['fuzz_rst']	[]
docutils.parsers.rst.languages.zh_cn	[]	[]
docutils.utils.urischemes	[]	[]
copy	[]	[]
docutils.io	['fuzz_rst', 'fuzz_rst_parse']	[]
docutils.parsers.rst.languages.lv	[]	[]
recommonmark	[]	[]
docutils.utils._roman_numerals	[]	[]
docutils.parsers.rst.languages.af	[]	[]
docutils.parsers.rst.languages	[]	[]
docutils.writers.manpage	[]	[]
os	[]	[]
docutils.parsers.rst.languages.eo	[]	[]
pathlib	[]	[]
time	[]	[]
warnings	[]	[]
docutils.writers.docutils_xml	[]	[]
docutils.writers.odf_odt.prepstyles	[]	[]
docutils.transforms.frontmatter	[]	[]
...fuzz_rst_parse	['fuzz_rst_parse']	[]
docutils.parsers.rst.languages.fa	[]	[]
docutils.languages.it	[]	[]
docutils.utils.punctuation_chars	[]	[]
docutils.readers	[]	[]
docutils.languages.ar	[]	[]
random	[]	[]
docutils.writers.xetex	[]	[]
importlib	[]	[]
docutils.languages.fr	[]	[]
docutils.writers.odf_odt	['fuzz_rst']	[]
docutils.readers.doctree	[]	[]
xml	[]	[]
atheris	[]	[]
docutils.parsers.rst.languages.zh_tw	[]	[]
sys	[]	[]
docutils.parsers.rst.languages.lt	[]	[]
docutils.writers.html4css1	[]	[]
docutils.utils._typing	[]	[]
docutils.nodes	['fuzz_rst', 'fuzz_rst_parse']	[]
docutils.parsers.rst.languages.en	[]	[]
codecs	[]	[]
docutils.parsers.rst.languages.ka	[]	[]
docutils.languages.cs	[]	[]
weakref	[]	[]
docutils	[]	[]
docutils.parsers.rst.languages.ar	[]	[]
unittest	[]	[]
docutils.parsers.rst.directives.images	[]	[]
tempfile	[]	[]
docutils.languages.sv	[]	[]
docutils.utils	['fuzz_rst', 'fuzz_rst_parse']	[]
docutils.languages.pl	[]	[]
docutils.languages.ru	[]	[]
docutils.languages.ko	[]	[]
docutils.transforms.references	[]	[]
docutils.utils.math.mathml_elements	[]	[]
docutils.transforms.misc	[]	[]
docutils.__main__	[]	[]
docutils.languages.zh_tw	[]	[]
docutils.languages.lt	[]	[]
docutils.parsers.rst.languages.pl	[]	[]
docutils.transforms.universal	[]	[]
docutils.parsers.rst.languages.fr	[]	[]
docutils.transforms.writer_aux	[]	[]
docutils.parsers.rst.languages.fi	[]	[]
shutil	[]	[]
docutils.transforms	[]	[]
docutils.languages.fi	[]	[]
docutils.utils.math.tex2mathml_extern	[]	[]
docutils.parsers.rst.languages.ja	[]	[]
docutils.parsers.rst.languages.ca	[]	[]
docutils.languages.ca	[]	[]
docutils.languages.da	[]	[]
docutils.core	[]	[]
docutils.parsers.rst.languages.de	[]	[]
docutils.parsers.commonmark_wrapper	[]	[]
docutils.languages.en	[]	[]
docutils.parsers.rst.directives	[]	[]
docutils.languages.zh_cn	[]	[]
docutils.languages.fa	[]	[]
	[]	[]
docutils.writers.null	[]	[]
docutils.languages.pt_br	[]	[]
docutils.parsers.rst.languages.sv	[]	[]
subprocess	[]	[]
zipfile	[]	[]
itertools	[]	[]
docutils.parsers.rst.languages.he	[]	[]
docutils.writers.s5_html	[]	[]
docutils.parsers.rst.directives.tables	[]	[]
docutils.parsers.rst.directives.misc	[]	[]
docutils.writers.latex2e	[]	[]
docutils.parsers.rst.languages.cs	[]	[]
unicodedata	[]	[]
docutils.languages.es	[]	[]
docutils.parsers.rst.directives.admonitions	[]	[]
docutils.utils.math.unichar2tex	[]	[]
docutils.writers	[]	[]
optparse	[]	[]
docutils.writers.html5_polyglot	[]	[]
docutils.examples	[]	[]
docutils.transforms.parts	[]	[]
mimetypes	[]	[]
docutils.parsers.rst	['fuzz_rst']	[]
urllib	[]	[]
docutils.parsers.rst.directives.html	[]	[]
argparse	[]	[]
docutils.languages.eo	[]	[]
docutils.utils.math.latex2mathml	[]	[]
locale	[]	[]
docutils.languages.gl	[]	[]
docutils.parsers.rst.languages.es	[]	[]
docutils.utils.math	[]	[]
docutils.parsers.rst.languages.it	[]	[]
docutils.utils.math.math2html	[]	[]
docutils.readers.pep	[]	[]
docutils.parsers.rst.directives.references	[]	[]
docutils.parsers.rst.languages.uk	[]	[]
docutils.parsers.rst.languages.da	[]	[]
docutils.languages.nl	[]	[]
docutils.writers.pep_html	[]	[]
docutils.parsers.rst.states	[]	[]
docutils.parsers.rst.directives.body	[]	[]
docutils.languages.uk	[]	[]
docutils.utils.math.tex2unichar	[]	[]
docutils.parsers.recommonmark_wrapper	[]	[]
docutils.parsers.null	[]	[]
docutils.utils.code_analyzer	[]	[]
configparser	[]	[]
docutils.languages	[]	[]
docutils.languages.de	[]	[]
docutils.parsers.rst.roles	[]	[]
docutils.parsers.rst.languages.sk	[]	[]
base64	[]	[]
PIL	[]	[]
docutils.utils.math.mathalphabet2unichar	[]	[]
docutils.languages.he	[]	[]
types	[]	[]
docutils.parsers.rst.directives.parts	[]	[]
docutils.parsers.rst.tableparser	['fuzz_table']	[]
docutils.writers._html_base	[]	[]
docutils.writers.odf_odt.pygmentsformatter	[]	[]
re	[]	[]
docutils.parsers	['fuzz_rst_parse']	[]
docutils.statemachine	['fuzz_rst', 'fuzz_table']	[]
docutils.transforms.peps	[]	[]
docutils.languages.ja	[]	[]
collections	[]	[]
docutils.parsers.rst.languages.nl	[]	[]
pygments	[]	[]
docutils.languages.ka	[]	[]
docutils.parsers.rst.languages.ru	[]	[]
docutils.readers.standalone	[]	[]
docutils.languages.af	[]	[]
...fuzz_table	['fuzz_table']	[]
typing	[]	[]
docutils.writers.pseudoxml	[]	[]
pprint	[]	[]
csv	[]	[]
docutils.parsers.rst.languages.ko	[]	[]
docutils.languages.lv	[]	[]
docutils.transforms.components	[]	[]
string	[]	[]
io	[]	[]
docutils.frontend	['fuzz_rst', 'fuzz_rst_parse']	[]
docutils.parsers.rst.languages.pt_br	[]	[]
docutils.parsers.rst.languages.gl	[]	[]
docutils.languages.sk	[]	[]

Directories in report

Directory