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

Table of contents

Project overview: imageio
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: fuzz_read
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Analyses and suggestions
Optimal target analysis
Remaining optimal interesting functions
All functions overview
Fuzz engine guidance
./tests/fuzzers/fuzz_read.py
Dictionary
Fuzzer function priority
Runtime coverage analysis
Complex functions with low coverage
Files and Directories in report
Files in report
Directories in report
Metadata section
Report generation date: 2024-09-08

Project overview: imageio

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
1.0%
14 / 1062
Cyclomatic complexity statically reachable by fuzzers
2.0%
75 / 3964
Runtime code coverage of functions
15.0%
159 / 1062

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.

Fuzzers overview

Fuzzer Fuzzer filename Functions Reached Functions unreached Fuzzer depth Files reached Basic blocks reached Cyclomatic complexity Details
fuzz_read ./tests/fuzzers/fuzz_read.py 87 1979 10 7 86 291 fuzz_read.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_read

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 0 123 73.2%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 45 26.7%
All colors 168 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
44 53 imageio.core.fetching.get_remote_file call site: 00053 imageio.core.fetching._fetch_file
19 33 imageio.core.fetching.get_remote_file call site: 00033 os.path.join
14 104 imageio.core.request.Request._parse_uri call site: 00104 .isinstance
11 129 imageio.core.imopen.imopen call site: 00129 imageio.core.request.Request.finish
10 6 imageio.v2.imread call site: 00006 pathlib.Path
8 146 imageio.core.request.Request.finish call site: 00146 imageio.core.request.Request.finish
3 24 imageio.core.request.Request._parse_uri call site: 00024 imageio.core.fetching.get_remote_file
3 122 imageio.core.request.Request._parse_uri call site: 00122 os.path.dirname
3 141 imageio.core.request.Request.finish call site: 00141 imageio.core.request.SeekableFileObject.close
3 161 imageio.core.imopen.imopen call site: 00161 .list
1 18 imageio.core.imopen.imopen call site: 00018 warnings.warn
1 119 imageio.core.request.Request._parse_uri call site: 00119 os.path.abspath

Runtime coverage analysis

Covered functions
228
Functions that are reachable but not covered
77
Reachable functions
87
Percentage of reachable functions covered
11.49%
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
...imageio.tests.fuzzers.fuzz_read 4
imageio 2
imageio.v2 7
imageio.core.imopen 13
imageio.core.request 34
imageio.core.fetching 43

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
imageio.plugins._tifffile.main imageio.plugins._tifffile 1 ['N/A'] 5 0 36 26 13 205 1 740 704
imageio.plugins.tifffile.TiffFormat.Writer._append_data imageio.plugins.tifffile 3 ['N/A', 'N/A', 'N/A'] 3 0 1 2 4 84 0 328 249
imageio.plugins.freeimagemulti.FreeimageMulti.Writer._append_data imageio.plugins.freeimagemulti 3 ['N/A', 'N/A', 'N/A'] 4 0 3 2 4 63 0 207 186
imageio.plugins._bsdf.load imageio.plugins._bsdf 3 ['N/A', 'N/A', 'N/A'] 8 0 1 2 4 59 0 215 176
imageio.plugins._swf.write_swf imageio.plugins._swf 4 ['N/A', 'N/A', 'N/A', 'N/A'] 8 0 6 3 4 56 0 181 133
imageio.plugins._dicom.process_directory imageio.plugins._dicom 3 ['N/A', 'N/A', 'N/A'] 5 0 12 4 5 54 0 183 123
imageio.plugins.pillowmulti.GIFFormat.Writer._append_data imageio.plugins.pillowmulti 3 ['N/A', 'N/A', 'N/A'] 5 0 1 2 4 48 0 159 100

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

Functions statically reachable by fuzzers
16.0%
167 / 1062
Cyclomatic complexity statically reachable by fuzzers
20.0%
811 / 3964

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

Fuzz engine guidance

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.

./tests/fuzzers/fuzz_read.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=['imageio.core.fetching.get_remote_file', 'imageio.core.request.Request._parse_uri', 'imageio.core.imopen.imopen', 'imageio.v2.imread', 'imageio.core.request.Request.finish']

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
re.sub 2443 656 26.85% []
imageio.core.imopen.imopen.loader 84 18 21.42% ['fuzz_read']
imageio.plugins._tifffile.TiffWriter.__init__ 60 0 0.0% []
imageio.plugins._tifffile.TiffWriter.save 108 0 0.0% []
imageio.plugins._tifffile.TiffWriter.save.compress 127 0 0.0% []
imageio.plugins._tifffile.TiffWriter.save.addtag 43 0 0.0% []
imageio.plugins._tifffile.TiffWriter.save.rational 212 0 0.0% []
imageio.plugins._tifffile.TiffWriter._write_remaining_pages.pack 62 0 0.0% []
imageio.plugins._tifffile.TiffFile.__init__ 55 15 27.27% []
imageio.plugins._tifffile.TiffFile.asarray 50 0 0.0% []
imageio.plugins._tifffile.TiffFile._generic_series 32 0 0.0% []
imageio.plugins._tifffile.TiffFile._shaped_series.append_series 62 0 0.0% []
imageio.plugins._tifffile.TiffFile._imagej_series.is_hyperstack 44 0 0.0% []
imageio.plugins._tifffile.TiffFile._ome_series 142 0 0.0% []
imageio.plugins._tifffile.TiffFile._lsm_fix_strip_offsets 36 0 0.0% []
imageio.plugins._tifffile.TiffPages._seek 47 0 0.0% []
imageio.plugins._tifffile.TiffPage.__init__ 147 0 0.0% []
imageio.plugins._tifffile.TiffPage.asarray 75 0 0.0% []
imageio.plugins._tifffile.TiffPage.asarray.unpack 65 0 0.0% []
imageio.plugins._tifffile.TiffPage.asrgb 39 0 0.0% []
imageio.plugins._tifffile.TiffPage.__str__ 34 0 0.0% []
imageio.plugins._tifffile.TiffPage.geotiff_tags 47 0 0.0% []
imageio.plugins._tifffile.TiffFrame.__init__ 33 0 0.0% []
imageio.plugins._tifffile.TiffTag.__init__ 50 0 0.0% []
imageio.plugins._tifffile.FileHandle.open 57 25 43.85% []
imageio.plugins._tifffile.TIFF.COMPRESSION 49 0 0.0% []
imageio.plugins._tifffile.read_tags 82 0 0.0% []
imageio.plugins._tifffile.read_uic_tag.read_int 62 0 0.0% []
imageio.plugins._tifffile.read_lsm_scaninfo 35 0 0.0% []
imageio.plugins._tifffile.read_cz_sem 33 0 0.0% []
imageio.plugins._tifffile.read_micromanager_metadata 34 0 0.0% []
imageio.plugins._tifffile.fluoview_description_metadata 47 0 0.0% []
imageio.plugins._tifffile.decode_lzw.next_code 49 0 0.0% []
imageio.plugins._tifffile.unpack_ints 43 0 0.0% []
imageio.plugins._tifffile.matlabstr2py.value 45 0 0.0% []
imageio.plugins._tifffile.matlabstr2py.parse 34 0 0.0% []
imageio.plugins._tifffile.hexdump 56 0 0.0% []
imageio.plugins._tifffile.pformat 31 0 0.0% []
imageio.plugins._tifffile.snipstr 39 0 0.0% []
imageio.plugins._tifffile.lsm2bin 43 0 0.0% []
imageio.plugins._tifffile.imshow 102 0 0.0% []
imageio.plugins._tifffile.main 55 0 0.0% []
imageio.plugins._tifffile.main.notnone 61 1 1.639% []
imageio.core.util.image_as_uint 41 2 4.878% []
asarray 34 10 29.41% []
pkg_resources.resource_filename 1578 23 1.457% []
ctypes.c_uint8.from_address 55 19 34.54% []
imageio.core.request.Request._parse_uri 96 31 32.29% ['fuzz_read']
imageio.core.fetching.get_remote_file 38 13 34.21% ['fuzz_read']
io.BytesIO.read 788 75 9.517% []
imageio.plugins._freeimage.FIBaseBitmap.get_meta_data 31 0 0.0% []
imageio.plugins._freeimage.FIBaseBitmap.set_meta_data.get_tag_type_number 41 2 4.878% []
imageio.plugins._freeimage.FIBitmap._get_type_and_shape 34 0 0.0% []
imageio.plugins.pyav.PyAVPlugin.__init__ 31 0 0.0% []
imageio.plugins.pyav.PyAVPlugin.write_frame 34 0 0.0% []
numpy.lib.stride_tricks.as_strided 93 23 24.73% []
PIL.Image.frombytes 1728 418 24.18% []
imageio.plugins.rawpy.RawPyPlugin.metadata 37 0 0.0% []
imageio.plugins.swf.SWFFormat.Reader._open 37 0 0.0% []
c.match 412 24 5.825% []
x.decode 239 61 25.52% []
imageio.plugins.dicom.DicomFormat.Reader._open 38 0 0.0% []
char.lower 195 12 6.153% []
imageio.plugins.pillow.PillowPlugin.__init__ 33 17 51.51% []
imageio.plugins.pillow.PillowPlugin.write 37 0 0.0% []
PIL.ImageSequence.Iterator 37 10 27.02% []
imageio.plugins.lytro.LytroLfrFormat.Reader._open 38 0 0.0% []
imageio.plugins.ffmpeg.FfmpegFormat.Reader._open 64 0 0.0% []
imageio.plugins.ffmpeg.FfmpegFormat.Reader._initialize 40 0 0.0% []
map.get 92 19 20.65% []
imageio.plugins.pillow_legacy.pil_get_frame 52 0 0.0% []
dtype.replace 172 22 12.79% []
PIL.GifImagePlugin.getdata 624 70 11.21% []
imageio.plugins.spe.SpePlugin._metadata_pre_v3 31 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
[] []
imageio.plugins._swf [] []
StdoutProgressIndicator [] []
threading [] []
resource_dirs [] []
bz2 [] []
imageio.v3 [] []
pkg_resources [] []
bsdf_cli [] []
PIL [] []
multiprocessing [] []
contextlib [] []
math [] []
ctypes [] []
imageio.plugins._bsdf [] []
imageio.plugins.lytro [] []
imageio.plugins.spe [] []
imageio.plugins.dicom [] []
os [] []
imageio.config [] []
faulthandler [] []
urlopen [] []
backports [] []
imageio.plugins._dicom [] []
imageio.core.legacy_plugin_wrapper [] []
imageio.testing [] []
struct [] []
fractions [] []
datetime [] []
imageio.plugins.pillow_legacy [] []
zlib [] []
imageio.config.plugins [] []
io [] []
imageio.core.findlib [] []
optparse [] []
imageio.plugins.tifffile [] []
doctest [] []
imageio.__main__ [] []
imageio.plugins.example [] []
imageio.freeze [] []
imageio.plugins.bsdf [] []
lxml [] []
[] []
argparse [] []
imageio.plugins.freeimage [] []
imageio.plugins.tifffile_v3 [] []
imp [] []
imageio.plugins.pillow_info [] []
json [] []
imageio.core.imopen ['fuzz_read'] []
imageio.v2 ['fuzz_read'] []
imageio.core.fetching ['fuzz_read'] []
imageio.plugins [] []
typing [] []
time [] []
imageio.plugins._tifffile [] []
pytest [] []
matplotlib [] []
binascii [] []
shutil [] []
imageio.plugins.grab [] []
imageio.plugins.feisem [] []
appdata_dir [] []
imageio.core.v3_plugin_api [] []
gc [] []
asarray [] []
xml [] []
platform [] []
Tkinter [] []
importlib [] []
urllib [] []
tifffile [] []
imageio.plugins.rawpy [] []
imageio ['fuzz_read'] []
...imageio.tests.fuzzers.fuzz_read ['fuzz_read'] []
imageio.core [] []
imageio.plugins.pyav [] []
rawpy [] []
Array [] []
imageio.core.request ['fuzz_read'] []
logging [] []
subprocess [] []
atheris [] []
warnings [] []
tkinter [] []
imageio.typing [] []
pillow_heif [] []
imageio.plugins.npz [] []
re [] []
av [] []
cv2 [] []
tkFileDialog [] []
lzma [] []
imageio_ffmpeg [] []
hashlib [] []
imageio.plugins.simpleitk [] []
zipfile [] []
numpy [] []
imageio.plugins.opencv [] []
tempfile [] []
pathlib [] []
imagecodecs [] []
imageio.core.util [] []
imageio.plugins.pillowmulti [] []
glob [] []
imageio.plugins.ffmpeg [] []
sys [] []
imageio.plugins.fits [] []
pprint [] []
collections [] []
imageio.plugins.freeimagemulti [] []
imageio.config.extensions [] []
imageio.plugins._freeimage [] []
imageio.core.format [] []
imageio.plugins.gdal [] []
enum [] []
imageio.plugins.swf [] []
imageio.plugins.pillow [] []

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_read fuzzerLogFile-fuzz_read.data fuzzerLogFile-fuzz_read.data.yaml all_cov.json