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

Fuzzer details

Fuzzer: ares_parse_reply_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

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 44 5.54%
gold [1:9] 0 0.0%
yellow [10:29] 1 0.12%
greenyellow [30:49] 2 0.25%
lawngreen 50+ 746 94.0%
All colors 793 100

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
68 68 1 :

['ares_dns_multistring_combined']

68 105 ares_dns_rr_get_bin call site: 00511 /src/c-ares/src/lib/record/ares_dns_record.c:847
7 7 1 :

['ares_array_move']

7 7 ares_array_insert_at call site: 00000 /src/c-ares/src/lib/dsa/ares_array.c:234
2 2 1 :

['__errno_location']

2 2 inet_ntop4 call site: 00471 /src/c-ares/src/lib/inet_ntop.c:100
2 2 1 :

['__errno_location']

2 2 inet_ntop6 call site: 00478 /src/c-ares/src/lib/inet_ntop.c:213
2 2 1 :

['ares_round_up_pow2_u32']

2 2 ares_round_up_pow2 call site: 00078 /src/c-ares/src/lib/util/ares_math.c:75
0 102 3 :

['ares_dns_multistring_add_own', 'ares_dns_multistring_clear', 'ares_dns_multistring_create']

0 137 ares_dns_rr_set_bin_own call site: 00274 /src/c-ares/src/lib/record/ares_dns_record.c:1198
0 44 1 :

['ares_dns_multistring_destroy']

0 44 ares_dns_parse_and_set_dns_abin call site: 00249 /src/c-ares/src/lib/record/ares_dns_parse.c:105
0 44 1 :

['ares_dns_multistring_destroy']

0 44 ares_dns_rr_set_abin_own call site: 00251 /src/c-ares/src/lib/record/ares_dns_record.c:1321
0 30 1 :

['ares_array_remove_last']

0 30 ares_dns_labels_add call site: 00586 /src/c-ares/src/lib/record/ares_dns_name.c:157
0 25 1 :

['ares_array_remove_at']

0 25 ares_dns_record_query_add call site: 00131 /src/c-ares/src/lib/record/ares_dns_record.c:274
0 25 1 :

['ares_array_remove_at']

0 25 ares_dns_record_rr_add call site: 00158 /src/c-ares/src/lib/record/ares_dns_record.c:435
0 13 1 :

['ares_dns_record_destroy']

0 13 ares_dns_parse_header call site: 00084 /src/c-ares/src/lib/record/ares_dns_parse.c:942

Runtime coverage analysis

Covered functions
224
Functions that are reachable but not covered
7
Reachable functions
228
Percentage of reachable functions covered
96.93%
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/c-ares/test/ares-test-fuzz.c 1
record/ares_dns_parse.c 32
str/ares_buf.c 30
ares_library_init.c 5
record/ares_dns_record.c 45
record/ares_dns_mapping.c 16
dsa/ares_array.c 12
record/ares_dns_multistring.c 9
util/ares_math.c 7
record/ares_dns_name.c 14
str/ares_str.c 6
inet_ntop.c 3
record/ares_dns_write.c 31
dsa/ares_llist.c 12

Fuzzer: ares_create_query_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

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 1360 70.4%
gold [1:9] 0 0.0%
yellow [10:29] 1 0.05%
greenyellow [30:49] 2 0.10%
lawngreen 50+ 567 29.3%
All colors 1930 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
2677 2738 5 :

['ares_init_options_servers', 'ares_malloc', 'ares_strdup', 'ares_malloc_zero', 'ares_threadsafety']

2677 2738 ares_init_by_options call site: 00072 /src/c-ares/src/lib/ares_options.c:270
93 93 1 :

['ares_event_thread_destroy']

93 357 ares_destroy call site: 01715 /src/c-ares/src/lib/ares_destroy.c:106
78 78 1 :

['ares_event_configchg_destroy']

250 3175 ares_destroy call site: 01692 /src/c-ares/src/lib/ares_destroy.c:52
10 10 1 :

['ares_thread_join']

172 3097 ares_destroy call site: 01693 /src/c-ares/src/lib/ares_destroy.c:62
4 8 3 :

['ares_malloc', 'strchr', 'gethostname']

4 36 init_by_defaults call site: 01435 /src/c-ares/src/lib/ares_init.c:173
2 2777 4 :

['ares_llist_destroy', 'htonl', 'ares_servers_update', 'ares_sconfig_append']

6 2813 init_by_defaults call site: 01417 /src/c-ares/src/lib/ares_init.c:148
2 2 1 :

['__errno_location']

2 2 ares_inet_net_pton_ipv6 call site: 00363 /src/c-ares/src/lib/inet_net_pton.c:399
2 2 1 :

['__errno_location']

2 2 inet_ntop4 call site: 00323 /src/c-ares/src/lib/inet_ntop.c:100
2 2 1 :

['__errno_location']

2 2 inet_ntop6 call site: 00329 /src/c-ares/src/lib/inet_ntop.c:213
2 2 1 :

['ares_round_up_pow2_u32']

2 2 ares_round_up_pow2 call site: 00133 /src/c-ares/src/lib/util/ares_math.c:75
0 248 2 :

['ares_buf_tag_rollback', 'config_lookup']

0 248 parse_resolvconf_line call site: 00000 /src/c-ares/src/lib/ares_sysconfig_files.c:597
0 247 1 :

['ares_sysconfig_set_options']

0 247 ares_init_by_environment call site: 01380 /src/c-ares/src/lib/ares_sysconfig_files.c:491

Runtime coverage analysis

Covered functions
269
Functions that are reachable but not covered
377
Reachable functions
640
Percentage of reachable functions covered
41.09%
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/c-ares/test/ares-test-fuzz-name.c 1
ares_library_init.c 8
ares_init.c 7
util/ares_threads.c 15
util/ares_rand.c 11
dsa/ares_slist.c 19
dsa/ares_llist.c 20
dsa/ares_htable_szvp.c 8
dsa/ares_htable.c 13
dsa/ares_htable_asvp.c 8
ares_options.c 2
str/ares_str.c 16
ares_update_servers.c 23
util/ares_math.c 7
ares_destroy.c 3
ares_close_sockets.c 4
str/ares_buf.c 53
util/ares_timeval.c 1
ares_process.c 30
ares_metrics.c 3
record/ares_dns_record.c 52
ares_timeout.c 6
dsa/ares_array.c 12
ares_conn.c 9
ares_socket.c 11
util/ares_uri.c 36
dsa/ares_htable_dict.c 8
inet_ntop.c 3
ares_hosts_file.c 2
inet_net_pton.c 6
ares_cookie.c 9
record/ares_dns_mapping.c 12
record/ares_dns_write.c 33
record/ares_dns_name.c 14
record/ares_dns_multistring.c 9
ares_send.c 3
ares_qcache.c 11
dsa/ares_htable_strvp.c 7
record/ares_dns_parse.c 32
ares_sysconfig.c 3
ares_sysconfig_files.c 6
str/ares_strsplit.c 3
ares_set_socket_functions.c 2
event/ares_event_thread.c 12
dsa/ares_htable_vpvp.c 7
event/ares_event_configchg.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
ares_getaddrinfo /src/c-ares/src/lib/ares_getaddrinfo.c 6 ['N/A', 'N/A', 'N/A', 'N/A', 'N/A', 'N/A'] 20 0 51 6 3 515 0 3309 524
ares_dup /src/c-ares/src/lib/ares_init.c 2 ['N/A', 'N/A'] 39 0 221 21 9 641 0 4132 71
ares_getnameinfo /src/c-ares/src/lib/ares_getnameinfo.c 6 ['N/A', 'N/A', 'int', 'int', 'N/A', 'N/A'] 21 0 51 6 3 506 0 3214 56
ares_iface_ips /src/c-ares/src/lib/util/ares_iface_ips.c 3 ['N/A', 'int', 'N/A'] 7 0 70 10 5 37 0 178 56
ares_hosts_entry_to_hostent /src/c-ares/src/lib/ares_hosts_file.c 3 ['N/A', 'int', 'N/A'] 8 0 91 14 6 33 0 268 47
ares_search /src/c-ares/src/lib/ares_search.c 6 ['N/A', 'N/A', 'int', 'int', 'N/A', 'N/A'] 20 0 139 16 7 455 0 2876 45
ares_dns_opt_get_name /src/c-ares/src/lib/record/ares_dns_mapping.c 2 ['int', 'short'] 1 0 48 10 11 2 0 38 38
ares_dns_opt_get_datatype /src/c-ares/src/lib/record/ares_dns_mapping.c 2 ['int', 'short'] 1 0 48 10 11 2 0 38 38
ares_evsys_epoll_init /src/c-ares/src/lib/event/ares_event_epoll.c 1 ['N/A'] 6 0 72 10 5 29 0 117 38

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

Functions statically reachable by fuzzers
84.0%
706 / 840
Cyclomatic complexity statically reachable by fuzzers
89.0%
4988 / 5610

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

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/c-ares/src/lib/str/ares_buf.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/record/ares_dns_multistring.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/ares_hosts_file.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_cookie.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/dsa/ares_llist.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/dsa/ares_htable_strvp.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/inet_ntop.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/util/ares_threads.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/record/ares_dns_write.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/event/ares_event_epoll.c [] []
/src/c-ares/src/lib/ares_parse_into_addrinfo.c [] []
/src/c-ares/src/lib/util/ares_timeval.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_timeout.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/dsa/ares_htable_asvp.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/dsa/ares_array.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/inet_net_pton.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_options.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_send.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_addrinfo2hostent.c [] []
/src/c-ares/src/lib/util/ares_iface_ips.c [] []
/src/c-ares/src/lib/ares_data.c [] []
/src/c-ares/src/lib/str/ares_str.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/event/ares_event_thread.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/dsa/ares_htable.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/util/ares_math.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/legacy/ares_parse_ptr_reply.c [] []
/src/c-ares/src/lib/ares_conn.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_gethostbyaddr.c [] []
/src/c-ares/src/lib/record/ares_dns_name.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/ares_sysconfig_files.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/record/ares_dns_mapping.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/event/ares_event_wake_pipe.c [] []
/src/c-ares/src/lib/ares_socket.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_getaddrinfo.c [] []
/src/c-ares/src/lib/ares_sortaddrinfo.c [] []
/src/c-ares/src/lib/util/ares_uri.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_init.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/dsa/ares_htable_dict.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_getnameinfo.c [] []
/src/c-ares/src/lib/ares_search.c [] []
/src/c-ares/src/lib/record/ares_dns_record.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/ares_query.c [] []
/src/c-ares/src/lib/ares_addrinfo_localhost.c [] []
/src/c-ares/test/ares-test-fuzz-name.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/test/ares-test-fuzz.c ['ares_parse_reply_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/dsa/ares_htable_vpvp.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_free_hostent.c [] []
/src/c-ares/src/lib/ares_qcache.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_metrics.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/util/ares_rand.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/event/ares_event_configchg.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_sysconfig.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/record/ares_dns_parse.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer']
/src/c-ares/src/lib/ares_close_sockets.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_destroy.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/event/ares_event_poll.c [] []
/src/c-ares/src/lib/event/ares_event_select.c [] []
/src/c-ares/src/lib/ares_freeaddrinfo.c [] []
/src/c-ares/src/lib/ares_set_socket_functions.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_free_string.c [] []
/src/c-ares/src/lib/dsa/ares_htable_szvp.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/dsa/ares_slist.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_process.c ['ares_create_query_fuzzer'] []
/src/c-ares/src/lib/ares_library_init.c ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer'] ['ares_parse_reply_fuzzer', 'ares_create_query_fuzzer']
/src/c-ares/src/lib/str/ares_strsplit.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']
/src/c-ares/src/lib/ares_update_servers.c ['ares_create_query_fuzzer'] ['ares_create_query_fuzzer']

Directories in report

Directory
/src/c-ares/test/
/src/c-ares/src/lib/
/src/c-ares/src/lib/event/
/src/c-ares/src/lib/dsa/
/src/c-ares/src/lib/str/
/src/c-ares/src/lib/util/
/src/c-ares/src/lib/record/
/src/c-ares/src/lib/legacy/