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

Table of contents

Project overview: libarchive
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: libarchive_fuzzer
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
/src/libarchive_fuzzer.cc
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: 2025-06-20

Project overview: libarchive

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
66.0%
842 / 1282
Cyclomatic complexity statically reachable by fuzzers
74.0%
7390 / 10009
Runtime code coverage of functions
77.0%
993 / 1282

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
libarchive_fuzzer /src/libarchive_fuzzer.cc 907 505 19 51 19755 7552 libarchive_fuzzer.cc

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 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 details

Fuzzer: libarchive_fuzzer

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 1190 26.6%
gold [1:9] 276 6.17%
yellow [10:29] 198 4.42%
greenyellow [30:49] 62 1.38%
lawngreen 50+ 2745 61.3%
All colors 4471 100

Fuzz blockers

The followings are the branches where fuzzer fails to bypass.

Unique non-covered Complexity Unique Reachable Complexities Unique Reachable Functions All non-covered Complexity All Reachable Complexity Function Name Function Callsite Blocked Branch
799 2293 19 :

['archive_entry_set_perm', 'archive_entry_set_rdev', 'archive_entry_set_dev', 'open', '__archive_ensure_cloexec_flag', 'archive_entry_set_uid', 'fstat', 'archive_entry_linkify', 'archive_entry_set_mtime', 'archive_entry_filetype', 'archive_set_error', 'archive_entry_pathname', 'lstat', 'archive_entry_set_gid', 'archive_entry_set_ino', 'archive_entry_set_size', '__errno_location', 'close', 'archive_entry_set_nlink']

799 2295 parse_file call site: 00984 /src/libarchive/libarchive/archive_read_support_format_mtree.c:1232
635 635 1 :

['cab_convert_path_separator_2']

635 643 archive_read_format_cab_read_header call site: 02647 /src/libarchive/libarchive/archive_read_support_format_cab.c:985
492 492 1 :

['skip_stream']

492 492 archive_read_format_7zip_read_data_skip call site: 02544 /src/libarchive/libarchive/archive_read_support_format_7zip.c:1169
231 231 1 :

['zip_read_mac_metadata']

231 231 archive_read_format_zip_seekable_read_header call site: 04318 /src/libarchive/libarchive/archive_read_support_format_zip.c:4337
165 165 1 :

['zisofs_read_data']

165 165 archive_read_format_iso9660_read_data call site: 03844 /src/libarchive/libarchive/archive_read_support_format_iso9660.c:1785
95 180 3 :

['archive_entry_copy_link', 'set_conversion_failed_error', '_archive_entry_copy_link_l']

95 180 header_pax_extension call site: 01463 /src/libarchive/libarchive/archive_read_support_format_tar.c:2103
91 686 7 :

['__archive_read_consume', 'move_reading_point', 'archive_set_error', '__archive_read_ahead', 'free', 'archive_string_concat', 'checksum_final']

91 686 read_toc call site: 01721 /src/libarchive/libarchive/archive_read_support_format_xar.c:602
87 172 4 :

['atol10', 'add_link', 'archive_set_error', 'strlen']

91 176 xml_start call site: 01808 /src/libarchive/libarchive/archive_read_support_format_xar.c:2052
48 48 1 :

['archive_entry_copy_symlink_w']

48 1483 archive_read_format_lha_read_header call site: 00647 /src/libarchive/libarchive/archive_read_support_format_lha.c:682
42 42 1 :

['lha_parse_linkname']

90 1698 archive_read_format_lha_read_header call site: 00631 /src/libarchive/libarchive/archive_read_support_format_lha.c:652
13 13 1 :

['execute_filter_audio']

13 13 execute_filter call site: 03094 /src/libarchive/libarchive/archive_read_support_format_rar.c:3889
10 10 2 :

['__archive_errx', '__errno_location']

10 10 archive_entry_gname call site: 01483 /src/libarchive/libarchive/archive_entry.c:441

Runtime coverage analysis

Covered functions
1000
Functions that are reachable but not covered
132
Reachable functions
907
Percentage of reachable functions covered
85.45%
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
/src/libarchive_fuzzer.cc 1
/src/libarchive/libarchive/archive_read.c 33
/src/libarchive/libarchive/archive_entry.c 99
/src/libarchive/libarchive/archive_read_support_filter_all.c 1
/src/libarchive/libarchive/archive_check_magic.c 6
/src/libarchive/libarchive/archive_util.c 5
/src/libarchive/libarchive/archive_string_sprintf.c 4
/src/libarchive/libarchive/archive_string.c 72
/src/libarchive/libarchive/archive_read_support_filter_bzip2.c 1
/src/libarchive/libarchive/archive_read_support_filter_compress.c 1
/src/libarchive/libarchive/archive_read_support_filter_gzip.c 1
/src/libarchive/libarchive/archive_read_support_filter_xz.c 3
/src/libarchive/libarchive/archive_read_support_filter_uu.c 1
/src/libarchive/libarchive/archive_read_support_filter_rpm.c 1
/src/libarchive/libarchive/archive_read_support_filter_lrzip.c 1
/src/libarchive/libarchive/archive_read_support_filter_lzop.c 1
/src/libarchive/libarchive/archive_read_support_filter_grzip.c 1
/src/libarchive/libarchive/archive_read_support_filter_lz4.c 1
/src/libarchive/libarchive/archive_read_support_filter_zstd.c 1
/src/libarchive/libarchive/archive_read_support_format_all.c 1
/src/libarchive/libarchive/archive_read_support_format_ar.c 11
/src/libarchive/libarchive/archive_read_support_format_cpio.c 8
/src/libarchive/libarchive/archive_endian.h 9
/src/libarchive/libarchive/archive_read_support_format_empty.c 4
/src/libarchive/libarchive/archive_read_support_format_lha.c 37
/src/libarchive/libarchive/archive_time.c 2
/src/libarchive/libarchive/archive_read_support_format_mtree.c 34
/src/libarchive/libarchive/archive_rb.c 11
/src/libarchive/libarchive/archive_entry_link_resolver.c 8
/src/libarchive/libarchive/archive_pack_dev.c 2
/src/libarchive/libarchive/archive_acl.c 14
/src/libarchive/libarchive/archive_entry_xattr.c 2
/src/libarchive/libarchive/archive_entry_sparse.c 2
/src/libarchive/libarchive/archive_read_support_format_tar.c 54
/src/libarchive/libarchive/archive_read_support_format_xar.c 49
/src/libarchive/libarchive/archive_read_support_format_warc.c 19
/src/libarchive/libarchive/archive_read_support_format_7zip.c 53
/src/libarchive/libarchive/archive_read_support_format_cab.c 43
/src/libarchive/libarchive/archive_read_support_format_rar.c 60
/src/libarchive/libarchive/archive_read_support_format_rar5.c 98
/src/libarchive/libarchive/archive_blake2sp_ref.c 6
/src/libarchive/libarchive/archive_blake2_impl.h 5
/src/libarchive/libarchive/archive_blake2s_ref.c 9
/src/libarchive/libarchive/archive_read_support_format_iso9660.c 50
/src/libarchive/libarchive/archive_read_support_format_zip.c 46
/src/libarchive/libarchive/archive_read_add_passphrase.c 7
/src/libarchive/libarchive/archive_virtual.c 5
/src/libarchive/libarchive/archive_read_support_format_raw.c 6
/src/libarchive/libarchive/archive_read_set_options.c 4
/src/libarchive/libarchive/archive_options.c 3
/src/libarchive/libarchive/archive_read_open_memory.c 7

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
parse_file /src/libarchive/libarchive/archive_read_support_format_mtree.c 5 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 10 0 868 155 55 158 0 1056 269
Ppmd7_EncodeSymbol /src/libarchive/libarchive/archive_ppmd7.c 3 ['N/A', 'N/A', 'int'] 7 0 757 58 17 23 0 149 149
archive_entry_acl_from_text_w /src/libarchive/libarchive/archive_entry.c 3 ['N/A', 'N/A', 'int'] 8 0 25 3 2 28 0 207 133
archive_entry_acl_text_w /src/libarchive/libarchive/archive_entry.c 2 ['N/A', 'int'] 11 0 53 6 3 84 0 713 105
read_mtree /src/libarchive/libarchive/archive_read_support_format_mtree.c 2 ['N/A', 'N/A'] 10 0 364 65 24 55 0 425 97
grzip_bidder_init /src/libarchive/libarchive/archive_read_support_filter_grzip.c 1 ['N/A'] 6 0 26 3 2 42 0 179 89
uudecode_filter_read /src/libarchive/libarchive/archive_read_support_filter_uu.c 2 ['N/A', 'N/A'] 7 0 1285 184 69 30 0 240 83
lz4_filter_read /src/libarchive/libarchive/archive_read_support_filter_lz4.c 2 ['N/A', 'N/A'] 9 0 265 40 12 35 0 226 71
XXH32_update /src/libarchive/libarchive/xxhash.c 3 ['N/A', 'N/A', 'int'] 1 0 1827 180 61 2 0 65 65
header_odc /src/libarchive/libarchive/archive_read_support_format_cpio.c 5 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 9 0 171 12 6 46 0 238 56

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

Functions statically reachable by fuzzers
74.0%
948 / 1282
Cyclomatic complexity statically reachable by fuzzers
85.0%
8467 / 10009

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

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.

/src/libarchive_fuzzer.cc

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=['parse_file_info', 'xml_end', 'seek_pack', 'xml_start', 'parse_file', 'xattr_free', 'slurp_central_directory', 'archive_read_format_zip_seekable_read_header', 'archive_entry_clear', 'archive_read_format_7zip_read_header']

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
archive_entry_set_digest 34 12 35.29% ['libarchive_fuzzer']
archive_entry_linkresolver_set_strategy 33 8 24.24% ['libarchive_fuzzer']
_archive_set_options 56 24 42.85% ['libarchive_fuzzer']
bzip2_filter_read 98 48 48.97% ['libarchive_fuzzer']
consume_header 46 22 47.82% ['libarchive_fuzzer']
set_error 40 14 35.0% ['libarchive_fuzzer']
read_stream 77 40 51.94% ['libarchive_fuzzer']
decompress 115 32 27.82% ['libarchive_fuzzer']
case_7Z_LZMA2 224 63 28.12%
setup_decode_folder 181 30 16.57% ['libarchive_fuzzer']
init_decompression 38 19 50.0% ['libarchive_fuzzer']
free_decompression 35 19 54.28% ['libarchive_fuzzer']
cab_consume_cfdata 80 31 38.75% ['libarchive_fuzzer']
cab_read_ahead_cfdata_deflate 173 63 36.41% ['libarchive_fuzzer']
parse_rockridge 128 57 44.53% ['libarchive_fuzzer']
read_CE 39 12 30.76% ['libarchive_fuzzer']
lzh_make_huffman_table 151 83 54.96% ['libarchive_fuzzer']
parse_file 151 38 25.16% ['libarchive_fuzzer']
read_data 39 11 28.20% ['libarchive_fuzzer']
read_symlink_stored 36 14 38.88% ['libarchive_fuzzer']
archive_read_format_tar_options 31 14 45.16% ['libarchive_fuzzer']
xar_read_header 168 17 10.11% ['libarchive_fuzzer']
read_toc 100 30 30.0% ['libarchive_fuzzer']
xml_end 325 122 37.53% ['libarchive_fuzzer']
parse_time 49 10 20.40% ['libarchive_fuzzer']
decompression_init 120 19 15.83% ['libarchive_fuzzer']
archive_read_format_zip_options 38 15 39.47% ['libarchive_fuzzer']
read_decryption_header 150 73 48.66% ['libarchive_fuzzer']
zip_read_data_zipx_bzip2 65 35 53.84% ['libarchive_fuzzer']
zip_read_data_zipx_xz 61 28 45.90% ['libarchive_fuzzer']
get_sconv_object 33 18 54.54% ['libarchive_fuzzer']
setup_converter 84 32 38.09% ['libarchive_fuzzer']

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
[] []
/src/libarchive/libarchive/archive_ppmd8.c [] []
/src/libarchive/libarchive/archive_blake2_impl.h ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_check_magic.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_ppmd7.c [] []
/src/libarchive/libarchive/archive_string_sprintf.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_zstd.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_xar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_virtual.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_mtree.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_7zip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_open_memory.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_options.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_rb.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_rpm.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_empty.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/filter_fork_posix.c [] []
/src/libarchive/libarchive/archive_cmdline.c [] []
/src/libarchive/libarchive/archive_blake2s_ref.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_hmac.c [] []
/src/libarchive/libarchive/archive_read_support_filter_program.c [] []
/src/libarchive/libarchive/archive_read_support_filter_compress.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_blake2sp_ref.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_set_options.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_all.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_all.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_lrzip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_acl.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_endian.h ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/xxhash.c [] []
/src/libarchive/libarchive/archive_read_support_format_cpio.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_cryptor.c [] []
/src/libarchive/libarchive/archive_read_support_filter_gzip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_lha.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_entry_xattr.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_xz.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_add_passphrase.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_lzop.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/usr/local/bin/../include/c++/v1/stdexcept [] []
/src/libarchive/libarchive/archive_read_support_format_rar5.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_warc.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_time.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_digest.c [] []
/src/libarchive/libarchive/archive_read_support_filter_lz4.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_iso9660.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_tar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_rar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_raw.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_pack_dev.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive_fuzzer.cc ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_entry_sparse.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_ar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_util.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_entry.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_string.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_cab.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_uu.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_entry_link_resolver.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_bzip2.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_zip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_grzip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']

Directories in report

Directory
/src/libarchive/libarchive/
/usr/local/bin/../include/c++/v1/
/src/

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
libarchive_fuzzer fuzzerLogFile-0-ZDSZeAAX7P.data fuzzerLogFile-0-ZDSZeAAX7P.data.yaml libarchive_fuzzer.covreport