Fuzz introspector
For issues and ideas: https://github.com/ossf/fuzz-introspector/issues
Project coverage

Table of contents

Project overview: markdown-it-py
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: fuzz_markdown
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Fuzzer: fuzz_markdown_extended
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Analyses and suggestions
Optimal target analysis
Remaining optimal interesting functions
All functions overview
Runtime coverage analysis
Complex functions with low coverage
Files and Directories in report
Files in report
Directories in report
Metadata section
Function call coverage
Function in each files in report
Report generation date: 2023-03-14

Project overview: markdown-it-py

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
11.1%
50/448
Cyclomatic complexity statically reachable by fuzzers
10.4%
162/1550
Runtime code coverage of functions
50.0%
224 / 448

Fuzzers overview

Fuzzer Fuzzer filename Functions Reached Functions unreached Fuzzer depth Files reached Basic blocks reached Cyclomatic complexity Details
fuzz_markdown /src/fuzz_markdown.py 26 436 5 8 14 80 fuzz_markdown.py
fuzz_markdown_extended /src/fuzz_markdown_extended.py 54 409 6 9 32 171 fuzz_markdown_extended.py

Project functions overview

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 details

Fuzzer: fuzz_markdown

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

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 3 7.89%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 35 92.1%
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
3 15 markdown_it.main.MarkdownIt.__init__ call site: 00015 inspect.getmembers

Runtime coverage analysis

Covered functions
190
Functions that are reachable but not covered
11
Reachable functions
26
Percentage of reachable functions covered
57.69%
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_markdown 5
markdown_it.main 13
markdown_it.parser_inline 2
markdown_it.parser_block 3
markdown_it.parser_core 3
markdown_it.renderer 2
markdown_it.ruler 2

Fuzzer: fuzz_markdown_extended

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

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 17 16.6%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 85 83.3%
All colors 102 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
6 1 ...fuzz_markdown_extended.TestOneInput call site: 00001 fdp.ConsumeIntInRange
3 35 markdown_it.main.MarkdownIt.__init__ call site: 00035 inspect.getmembers
1 21 ...fuzz_markdown_extended.TestOneInput call site: 00021 markdown_it.main.MarkdownIt.__init__
1 46 markdown_it.main.MarkdownIt.configure call site: 00046 markdown_it.main.MarkdownIt.render
1 63 ...fuzz_markdown_extended.TestOneInput call site: 00063 markdown_it.main.MarkdownIt.normalizeLink
1 70 markdown_it.common.normalize_url.normalizeLink call site: 00070 markdown_it.main.MarkdownIt.normalizeLinkText
1 77 markdown_it.common.normalize_url.normalizeLinkText call site: 00077 markdown_it.main.MarkdownIt.disable
1 86 markdown_it.main.MarkdownIt.disable call site: 00086 markdown_it.main.MarkdownIt.enable
1 94 markdown_it.main.MarkdownIt.enable call site: 00094 markdown_it.main.MarkdownIt.validateLink
1 100 markdown_it.common.normalize_url.validateLink call site: 00100 markdown_it.main.MarkdownIt.configure

Runtime coverage analysis

Covered functions
190
Functions that are reachable but not covered
24
Reachable functions
54
Percentage of reachable functions covered
55.56%
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
...fuzz_markdown_extended 14
markdown_it.main 20
markdown_it.parser_inline 2
markdown_it.parser_block 3
markdown_it.parser_core 3
markdown_it.renderer 2
markdown_it.ruler 6
markdown_it.common.normalize_url 11

Analyses and suggestions

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
markdown_it.rules_block.reference.reference markdown_it.rules_block.reference 4 ['N/A', 'N/A', 'N/A', 'N/A'] 1 0 2 32 16 19 0 73 70
markdown_it.rules_core.smartquotes.smartquotes markdown_it.rules_core.smartquotes 1 ['N/A'] 2 0 1 3 4 15 0 60 51
markdown_it.rules_core.linkify.linkify markdown_it.rules_core.linkify 1 ['N/A'] 1 0 5 14 9 19 0 66 48
markdown_it.rules_core.replacements.replace markdown_it.rules_core.replacements 1 ['N/A'] 1 0 2 5 5 13 0 47 47
markdown_it.renderer.RendererHTML.fence markdown_it.renderer 5 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 2 0 1 5 5 15 0 51 45
markdown_it.rules_block.list.list_block markdown_it.rules_block.list 4 ['N/A', 'N/A', 'N/A', 'N/A'] 1 0 3 30 15 14 0 61 40
markdown_it.tree.SyntaxTreeNode.__init__ markdown_it.tree 3 ['N/A', 'N/A', 'N/A'] 3 0 4 5 5 12 0 43 37

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

Functions statically reachable by fuzzers
31.2%
140/448
Cyclomatic complexity statically reachable by fuzzers
31.6%
491 / 1550

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

Runtime coverage analysis

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
markdown_it.rules_core.smartquotes.process_inlines 97 0 0.0% []
markdown_it.rules_core.linkify.linkify 75 0 0.0% []
markdown_it.rules_block.table.table 127 0 0.0% []
markdown_it.rules_inline.strikethrough._postProcess 37 0 0.0% []

Files and Directories in report

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
[] []
markdown_it.presets [] []
markdown_it.rules_inline.link [] []
warnings [] []
markdown_it.presets.zero [] []
markdown_it._compat [] []
markdown_it.rules_core.normalize [] []
markdown_it.utils [] []
markdown_it.helpers [] []
markdown_it.rules_inline.html_inline [] []
markdown_it.cli.parse [] []
markdown_it.rules_block.hr [] []
html [] []
mdurl [] []
markdown_it.helpers.parse_link_title [] []
markdown_it.rules_inline [] []
markdown_it.rules_inline.emphasis [] []
markdown_it.rules_block.heading [] []
[] []
atheris [] []
markdown_it.rules_core.linkify [] []
markdown_it._punycode [] []
markdown_it.rules_inline.strikethrough [] []
markdown_it.token [] []
markdown_it.rules_core [] []
markdown_it.presets.default [] []
markdown_it.rules_inline.balance_pairs [] []
markdown_it.rules_block.fence [] []
markdown_it.rules_inline.text_collapse [] []
markdown_it.ruler ['fuzz_markdown', 'fuzz_markdown_extended'] []
markdown_it.rules_block.table [] []
markdown_it.cli [] []
markdown_it.common.html_blocks [] []
markdown_it.rules_inline.escape [] []
markdown_it [] []
linkify_it [] []
markdown_it.rules_inline.autolink [] []
textwrap [] []
markdown_it.rules_inline.entity [] []
sys [] []
dataclasses [] []
markdown_it.rules_block.list [] []
markdown_it.parser_block ['fuzz_markdown', 'fuzz_markdown_extended'] []
markdown_it.rules_inline.image [] []
markdown_it.rules_core.replacements [] []
markdown_it.renderer ['fuzz_markdown', 'fuzz_markdown_extended'] []
markdown_it.rules_inline.state_inline [] []
markdown_it.rules_core.smartquotes [] []
markdown_it.rules_block [] []
markdown_it.rules_core.state_core [] []
markdown_it.rules_inline.text [] []
markdown_it.parser_core ['fuzz_markdown', 'fuzz_markdown_extended'] []
markdown_it.common.html_re [] []
markdown_it.common.utils [] []
markdown_it.presets.commonmark [] []
markdown_it.helpers.parse_link_label [] []
markdown_it.rules_block.reference [] []
...fuzz_markdown ['fuzz_markdown'] []
markdown_it.rules_core.inline [] []
re [] []
markdown_it.rules_block.code [] []
markdown_it.rules_core.block [] []
markdown_it.helpers.parse_link_destination [] []
markdown_it.common.entities [] []
inspect [] []
markdown_it.common.normalize_url ['fuzz_markdown_extended'] []
codecs [] []
collections [] []
markdown_it.rules_block.lheading [] []
markdown_it.parser_inline ['fuzz_markdown', 'fuzz_markdown_extended'] []
pathlib [] []
markdown_it.common [] []
...fuzz_markdown_extended ['fuzz_markdown_extended'] []
markdown_it.rules_block.paragraph [] []
argparse [] []
markdown_it.tree [] []
markdown_it.main ['fuzz_markdown', 'fuzz_markdown_extended'] []
typing [] []
markdown_it.rules_inline.newline [] []
logging [] []
markdown_it.rules_inline.backticks [] []
markdown_it.rules_block.state_block [] []
markdown_it.rules_block.blockquote [] []
markdown_it.rules_block.html_block [] []

Directories in report

Directory

Metadata section

This sections shows the raw data that is used to produce this report. This is mainly used for further processing and developer debugging.

Fuzzer Calltree file Program data file Coverage file
fuzz_markdown fuzzerLogFile-fuzz_markdown.data fuzzerLogFile-fuzz_markdown.data.yaml all_cov.json
fuzz_markdown_extended fuzzerLogFile-fuzz_markdown_extended.data fuzzerLogFile-fuzz_markdown_extended.data.yaml all_cov.json

Function call coverage

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