High level conclusions

Fuzzer parso_pep8_fuzz is blocked:

The runtime code coverage of parso_pep8_fuzz covers 17.39% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzer parso_fuzz is blocked:

The runtime code coverage of parso_fuzz covers 19.04% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzer parso_extended_fuzz is blocked:

The runtime code coverage of parso_extended_fuzz covers 19.23% of its statically reachable code. This means there is some place that blocks the fuzzer to continue exploring more code at run time.

Fuzzers reach 14.54% of cyclomatic complexity.

Fuzzers reach 14.93% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

108/723

Cyclomatic complexity statically reachable by fuzzers

356/2447

Runtime code coverage of functions

433 / 723

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	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

Fuzzer: parso_extended_fuzz

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	7	18.4%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	31	81.5%
All colors	38	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	4	...parso_extended_fuzz.fuzz_dump	call site: 00004	parso.grammar.load_grammar
2	31	...parso_extended_fuzz.fuzz_errors	call site: 00031	...parso_extended_fuzz.fuzz_errors
1	23	parso.grammar.load_grammar	call site: 00023	grammar.parse
1	25	...parso_extended_fuzz.fuzz_dump	call site: 00025	...parso_extended_fuzz.fuzz_errors
1	36	...parso_extended_fuzz.TestOneInput	call site: 00036	...parso_extended_fuzz.fuzz_errors

Runtime coverage analysis

Covered functions

302

Functions that are reachable but not covered

21

Reachable functions

26

Percentage of reachable functions covered

19.23%

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
...parso_extended_fuzz	9
parso	3
parso.grammar	8
parso.utils	6

Fuzzer: parso_diff_fuzz

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	106	56.3%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	82	43.6%
All colors	188	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
38	88	parso.python.diff.DiffParser._parse	call site: 00088	parso.python.diff._NodesTree._copy_nodes
24	162	parso.python.diff._get_previous_leaf_if_indentation	call site: 00162	parso.python.diff._assert_valid_graph
14	50	parso.python.diff.DiffParser._diff_tokenize	call site: 00050	parso.python.diff._suite_or_file_input_is_valid
4	134	parso.utils.split_lines	call site: 00134	parso.python.diff.DiffParser._parse
4	144	parso.python.diff._get_next_leaf_if_indentation	call site: 00144	parso.python.diff._update_positions
3	36	parso.python.diff.DiffParser.update	call site: 00036	parso.python.diff.DiffParser._copy_from_old_parser
3	44	parso.python.diff._ends_with_newline	call site: 00044	parso.python.diff.DiffParser._parse
3	80	parso.python.diff._NodesTree.add_parsed_nodes	call site: 00080	parso.python.diff._NodesTreeNode.add_tree_nodes
3	158	parso.python.diff._NodesTree.close	call site: 00158	parso.python.diff._assert_valid_graph
2	4	...parso_diff_fuzz.TestOneInput	call site: 00004	parso.grammar.load_grammar
2	40	parso.python.diff._ends_with_newline	call site: 00040	leaf.get_previous_leaf
2	154	parso.python.diff._NodesTree.close	call site: 00154	.len

Runtime coverage analysis

Covered functions

302

Functions that are reachable but not covered

75

Reachable functions

108

Percentage of reachable functions covered

30.56%

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
...parso_diff_fuzz	6
parso	3
parso.grammar	8
parso.utils	13
parso.python.diff	77
parso.python.parser	3

Fuzzer: parso_fuzz

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	3	12.5%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	21	87.5%
All colors	24	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	3	...parso_fuzz.TestOneInput	call site: 00003	parso.grammar.load_grammar
1	22	parso.grammar.load_grammar	call site: 00022	grammar.parse

Runtime coverage analysis

Covered functions

301

Functions that are reachable but not covered

17

Reachable functions

21

Percentage of reachable functions covered

19.05%

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
...parso_fuzz	3
parso	3
parso.grammar	8
parso.utils	6

Fuzzer: parso_pep8_fuzz

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	3	11.5%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	23	88.4%
All colors	26	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	4	...parso_pep8_fuzz.TestOneInput	call site: 00004	parso.grammar.load_grammar
1	23	parso.grammar.load_grammar	call site: 00023	grammar.parse

Runtime coverage analysis

Covered functions

301

Functions that are reachable but not covered

19

Reachable functions

23

Percentage of reachable functions covered

17.39%

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
...parso_pep8_fuzz	5
parso	3
parso.grammar	8
parso.utils	6

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
parso.pgen2.generator.generate_grammar	parso.pgen2.generator	2	['N/A', 'N/A']	5	0	3	2	4	120	1	400	336
parso.grammar.Grammar.parse	parso.grammar	9	['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A']	4	0	3	14	9	90	0	295	226
parso.python.pep8.PEP8Normalizer.visit_leaf	parso.python.pep8	2	['N/A', 'N/A']	3	0	5	5	5	33	6	148	121
parso.python.errors._NamedExprRule.is_issue	parso.python.errors	2	['N/A', 'N/A']	2	0	4	4	5	16	0	81	69
parso.python.pep8.PEP8Normalizer._visit_node	parso.python.pep8	2	['N/A', 'N/A']	1	0	7	27	14	19	8	73	44
parso.python.errors._get_rhs_name	parso.python.errors	2	['N/A', 'N/A']	2	0	0	33	16	5	2	46	35

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

Functions statically reachable by fuzzers

326/723

Cyclomatic complexity statically reachable by fuzzers

1160 / 2447

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	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

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
parso.grammar.Grammar.parse	42	19	45.23%	[]
parso.python.pep8.PEP8Normalizer._visit_node	76	36	47.36%	[]
parso.python.diff.DiffParser._diff_tokenize	37	16	43.24%	['parso_diff_fuzz']
parso.python.diff._NodesTree._copy_nodes	84	0	0.0%	['parso_diff_fuzz']

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
	[]	[]
parso.pgen2.grammar_parser	[]	[]
parso.python.tokenize	[]	[]
...parso_fuzz	['parso_fuzz']	[]
parso.parser	[]	[]
parso.pgen2	[]	[]
gc	[]	[]
	[]	[]
parso.python.tree	[]	[]
warnings	[]	[]
parso.pgen2.generator	[]	[]
...parso_extended_fuzz	['parso_extended_fuzz']	[]
re	[]	[]
...parso_diff_fuzz	['parso_diff_fuzz']	[]
platform	[]	[]
parso.python.errors	[]	[]
os	[]	[]
itertools	[]	[]
atheris	[]	[]
parso._compatibility	[]	[]
parso	['parso_extended_fuzz', 'parso_diff_fuzz', 'parso_fuzz', 'parso_pep8_fuzz']	[]
parso.tree	[]	[]
pickle	[]	[]
parso.python.diff	['parso_diff_fuzz']	[]
parso.python.pep8	[]	[]
shutil	[]	[]
parso.utils	['parso_extended_fuzz', 'parso_diff_fuzz', 'parso_fuzz', 'parso_pep8_fuzz']	[]
difflib	[]	[]
collections	[]	[]
codecs	[]	[]
parso.cache	[]	[]
hashlib	[]	[]
parso.python	[]	[]
ast	[]	[]
parso.file_io	[]	[]
parso.python.parser	['parso_diff_fuzz']	[]
pathlib	[]	[]
time	[]	[]
...parso_pep8_fuzz	['parso_pep8_fuzz']	[]
logging	[]	[]
parso.grammar	['parso_extended_fuzz', 'parso_diff_fuzz', 'parso_fuzz', 'parso_pep8_fuzz']	[]
typing	[]	[]
parso.python.token	[]	[]
parso.normalizer	[]	[]
parso.python.prefix	[]	[]

Directories in report

Directory

This section shows a chosen list of functions / methods calls and their relative coverage information. By static analysis of the target project code, all of these function call and their caller information, including the source file or class and line number that initiate the call are captured. Column 1 is the function name of that selected functions or methods. Column 2 of each row indicate if the target function covered by any fuzzer calltree information. Column 3 lists all fuzzers (or no fuzzers at all) that have coered that particular function call dynamically. Column 4 shows list of parent function for the specific function call, while column 5 shows possible blocker functions that make the fuzzers fail to reach the specific functions. Both column 4 and 5 will only show information if none of the fuzzers cover the target function calls.

Function in each files in report

Target sink	Callsite location	Reached by fuzzer	Function call path	Covered by fuzzer	Possible branch blockers