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: 2024-07-23

Project overview: libarchive

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
66.0%
837 / 1275
Cyclomatic complexity statically reachable by fuzzers
74.0%
7242 / 9853
Runtime code coverage of functions
59.0%
752 / 1275

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 901 502 8 42 19371 7402 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 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 0 104 19.4%
gold [1:9] 44 8.20%
yellow [10:29] 29 5.41%
greenyellow [30:49] 22 4.10%
lawngreen 50+ 337 62.8%
All colors 536 100

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
872 874 2 :

['archive_entry_set_size', 'read_symlink_stored']

872 874 read_header call site: 00000 /src/libarchive/libarchive/archive_read_support_format_rar.c:1820
788 2267 19 :

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

788 2269 parse_file call site: 00000 /src/libarchive/libarchive/archive_read_support_format_mtree.c:1232
645 645 1 :

['lha_replace_path_separator']

723 1424 archive_read_format_lha_read_header call site: 00000 /src/libarchive/libarchive/archive_read_support_format_lha.c:693
632 632 1 :

['cab_convert_path_separator_2']

632 640 archive_read_format_cab_read_header call site: 00000 /src/libarchive/libarchive/archive_read_support_format_cab.c:980
519 519 1 :

['cab_consume_cfdata']

519 1031 archive_read_format_cab_read_data call site: 00000 /src/libarchive/libarchive/archive_read_support_format_cab.c:1040
501 899 6 :

['inflateReset', 'inflateSetDictionary', 'inflate', 'truncated_error', 'cab_minimum_consume_cfdata', '__archive_read_ahead']

501 1207 cab_read_ahead_cfdata_deflate call site: 00000 /src/libarchive/libarchive/archive_read_support_format_cab.c:1495
485 485 1 :

['read_Bools']

487 967 read_Digests call site: 00000 /src/libarchive/libarchive/archive_read_support_format_7zip.c:1851
485 485 1 :

['read_Bools']

485 1937 read_Times call site: 00000 /src/libarchive/libarchive/archive_read_support_format_7zip.c:2870
478 478 1 :

['skip_stream']

478 478 archive_read_format_7zip_read_data_skip call site: 00000 /src/libarchive/libarchive/archive_read_support_format_7zip.c:936
299 661 17 :

['_warc_rduri', '_warc_skip', '_warc_rdrtm', 'archive_entry_copy_pathname', '__archive_read_consume', '_warc_find_eoh', 'archive_entry_set_size', 'archive_entry_set_perm', 'archive_entry_set_ctime', '_warc_rdlen', 'archive_entry_set_filetype', '__archive_read_ahead', 'realloc', 'archive_entry_set_mtime', '_warc_rdtyp', '_warc_rdver', '_warc_rdmtm']

299 1200 _warc_rdhdr call site: 00000 /src/libarchive/libarchive/archive_read_support_format_warc.c:273
229 229 1 :

['zip_read_mac_metadata']

229 229 archive_read_format_zip_seekable_read_header call site: 00000 /src/libarchive/libarchive/archive_read_support_format_zip.c:4363
206 206 1 :

['gnu_sparse_old_read']

206 206 header_gnutar call site: 00000 /src/libarchive/libarchive/archive_read_support_format_tar.c:2890

Runtime coverage analysis

Covered functions
754
Functions that are reachable but not covered
302
Reachable functions
901
Percentage of reachable functions covered
66.48%
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.
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 26
/src/libarchive/libarchive/archive_entry.c 18
/src/libarchive/libarchive/archive_read_support_filter_all.c 1
/src/libarchive/libarchive/archive_check_magic.c 6
/src/libarchive/libarchive/archive_util.c 4
/src/libarchive/libarchive/archive_string_sprintf.c 3
/src/libarchive/libarchive/archive_string.c 23
/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 2
/src/libarchive/libarchive/archive_read_support_format_cpio.c 2
/src/libarchive/libarchive/archive_read_support_format_empty.c 2
/src/libarchive/libarchive/archive_read_support_format_lha.c 3
/src/libarchive/libarchive/archive_read_support_format_mtree.c 9
/src/libarchive/libarchive/archive_rb.c 1
/src/libarchive/libarchive/archive_read_support_format_tar.c 10
/src/libarchive/libarchive/archive_read_support_format_xar.c 2
/src/libarchive/libarchive/archive_endian.h 5
/src/libarchive/libarchive/archive_read_support_format_warc.c 3
/src/libarchive/libarchive/archive_read_support_format_7zip.c 3
/src/libarchive/libarchive/archive_read_support_format_cab.c 3
/src/libarchive/libarchive/archive_read_support_format_rar.c 2
/src/libarchive/libarchive/archive_read_support_format_rar5.c 17
/src/libarchive/libarchive/archive_read_support_format_iso9660.c 13
/src/libarchive/libarchive/archive_read_support_format_zip.c 7
/src/libarchive/libarchive/archive_read_support_format_raw.c 2
/src/libarchive/libarchive/archive_read_set_options.c 3
/src/libarchive/libarchive/archive_options.c 3
/src/libarchive/libarchive/archive_read_add_passphrase.c 3
/src/libarchive/libarchive/archive_read_open_memory.c 7
/src/libarchive/libarchive/archive_virtual.c 4

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 55 156 0 1045 261
Ppmd7_EncodeSymbol /src/libarchive/libarchive/archive_ppmd7.c 3 ['N/A', 'N/A', 'int'] 7 0 748 52 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 0 206 132
archive_entry_acl_text_w /src/libarchive/libarchive/archive_entry.c 2 ['N/A', 'int'] 11 0 53 6 3 84 0 710 105
read_mtree /src/libarchive/libarchive/archive_read_support_format_mtree.c 2 ['N/A', 'N/A'] 10 0 364 65 24 55 0 421 97
grzip_bidder_init /src/libarchive/libarchive/archive_read_support_filter_grzip.c 1 ['N/A'] 6 0 26 3 2 42 0 177 90
uudecode_filter_read /src/libarchive/libarchive/archive_read_support_filter_uu.c 2 ['N/A', 'N/A'] 7 0 1285 184 69 30 0 238 83
lz4_filter_read /src/libarchive/libarchive/archive_read_support_filter_lz4.c 2 ['N/A', 'N/A'] 9 0 265 40 12 35 0 224 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 45 0 235 55

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

Functions statically reachable by fuzzers
74.0%
940 / 1275
Cyclomatic complexity statically reachable by fuzzers
84.0%
8310 / 9853

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.

/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=['archive_read_format_iso9660_bid', '__archive_check_magic', 'archive_string_ensure', 'archive_strncat', 'read_zip64_eocd', 'isSVD', 'archive_string_append', 'archive_string_append_from_wcs', '__archive_read_ahead', 'detect_form']

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_linkresolver_set_strategy 33 8 24.24% []
_archive_set_options 56 24 42.85% ['libarchive_fuzzer']
ReduceOrder 63 15 23.80% []
client_skip_proxy 32 17 53.12% ['libarchive_fuzzer']
peek_at_header 66 27 40.90% []
consume_header 46 22 47.82% []
lzma_bidder_bid 49 25 51.02% []
archive_read_format_7zip_read_header 156 66 42.30% ['libarchive_fuzzer']
read_stream 77 31 40.25% ['libarchive_fuzzer']
extract_pack_stream 129 47 36.43% ['libarchive_fuzzer']
decompress 115 28 24.34% ['libarchive_fuzzer']
case_7Z_LZMA2 223 30 13.45%
get_uncompressed_data 38 16 42.10% ['libarchive_fuzzer']
read_CodersInfo 81 37 45.67% ['libarchive_fuzzer']
setup_decode_folder 181 29 16.02% ['libarchive_fuzzer']
init_decompression 36 19 52.77% ['libarchive_fuzzer']
read_Header 284 117 41.19% ['libarchive_fuzzer']
free_decompression 35 15 42.85% ['libarchive_fuzzer']
archive_read_format_cab_read_data 47 15 31.91% ['libarchive_fuzzer']
cab_next_cfdata 114 60 52.63% ['libarchive_fuzzer']
cab_read_ahead_cfdata_deflate 173 59 34.10% ['libarchive_fuzzer']
cab_read_data 38 14 36.84% ['libarchive_fuzzer']
archive_read_format_cpio_read_header 75 33 44.0% ['libarchive_fuzzer']
isJolietSVD 31 16 51.61% ['libarchive_fuzzer']
isEVD 43 10 23.25% ['libarchive_fuzzer']
archive_read_format_iso9660_read_header 182 74 40.65% ['libarchive_fuzzer']
choose_volume 64 29 45.31% ['libarchive_fuzzer']
parse_file_info 203 86 42.36% ['libarchive_fuzzer']
read_CE 39 12 30.76% ['libarchive_fuzzer']
lha_read_file_extended_header 259 117 45.17% ['libarchive_fuzzer']
lzh_read_blocks 185 85 45.94% ['libarchive_fuzzer']
lzh_make_huffman_table 151 78 51.65% ['libarchive_fuzzer']
parse_escapes 70 20 28.57% []
parse_file 151 36 23.84% []
parse_keyword 248 81 32.66% []
read_data 39 11 28.20% ['libarchive_fuzzer']
parse_filter 42 20 47.61% ['libarchive_fuzzer']
archive_read_format_rar_seek_data 128 12 9.375% ['libarchive_fuzzer']
parse_file_extra_redir 56 29 51.78% ['libarchive_fuzzer']
parse_file_extra_owner 65 22 33.84% ['libarchive_fuzzer']
parse_tables 129 58 44.96% ['libarchive_fuzzer']
archive_read_format_tar_options 31 14 45.16% ['libarchive_fuzzer']
tar_read_header 195 83 42.56% ['libarchive_fuzzer']
header_common 137 37 27.00% ['libarchive_fuzzer']
_warc_rdhdr 134 29 21.64% ['libarchive_fuzzer']
xar_read_header 168 17 10.11% ['libarchive_fuzzer']
read_toc 100 30 30.0% ['libarchive_fuzzer']
xml2_read_toc 49 12 24.48% ['libarchive_fuzzer']
decompression_init 120 19 15.83% ['libarchive_fuzzer']
archive_read_format_zip_options 38 15 39.47% ['libarchive_fuzzer']
zip_read_local_file_header 318 172 54.08% ['libarchive_fuzzer']
process_extra 299 130 43.47% ['libarchive_fuzzer']
read_decryption_header 150 65 43.33% ['libarchive_fuzzer']
get_sconv_object 33 18 54.54% ['libarchive_fuzzer']
setup_converter 84 28 33.33% ['libarchive_fuzzer']
utf16_to_unicode 38 14 36.84% ['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_read_support_filter_zstd.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_string.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_empty.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/usr/local/bin/../include/c++/v1/stdexcept [] []
/src/libarchive/libarchive/archive_read_support_filter_rpm.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_program.c [] []
/src/libarchive/libarchive/archive_entry_xattr.c [] []
/src/libarchive/libarchive/archive_read_support_format_tar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_add_passphrase.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_string_sprintf.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_rb.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_entry_sparse.c [] []
/src/libarchive/libarchive/archive_read_support_filter_grzip.c ['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_options.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_check_magic.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_compress.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_entry.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_xar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_all.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_open_memory.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive_fuzzer.cc ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_7zip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_gzip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read.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_rar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_bzip2.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/filter_fork_posix.c [] []
/src/libarchive/libarchive/archive_cryptor.c [] []
/src/libarchive/libarchive/archive_read_support_format_lha.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_cmdline.c [] []
/src/libarchive/libarchive/archive_read_support_format_cab.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_mtree.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_blake2_impl.h [] []
/src/libarchive/libarchive/archive_acl.c [] []
/src/libarchive/libarchive/archive_pack_dev.c [] []
/src/libarchive/libarchive/archive_read_support_format_zip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_raw.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_xz.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_lz4.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_lrzip.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_digest.c [] []
/src/libarchive/libarchive/archive_read_support_filter_lzop.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_util.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_hmac.c [] []
/src/libarchive/libarchive/archive_read_support_filter_uu.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_filter_all.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_virtual.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_blake2sp_ref.c [] []
/src/libarchive/libarchive/archive_entry_link_resolver.c [] []
/src/libarchive/libarchive/archive_read_set_options.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_ppmd8.c [] []
/src/libarchive/libarchive/archive_read_support_format_ar.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_read_support_format_warc.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_ppmd7.c [] []
/src/libarchive/libarchive/archive_read_support_format_rar5.c ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_endian.h ['libarchive_fuzzer'] ['libarchive_fuzzer']
/src/libarchive/libarchive/archive_blake2s_ref.c [] []

Directories in report

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

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-PIwc4Tl4Oe.data fuzzerLogFile-0-PIwc4Tl4Oe.data.yaml libarchive_fuzzer.covreport