High level conclusions

Fuzzers reach 89.18% of cyclomatic complexity.

Fuzzers reach 88.19% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

381/432

Cyclomatic complexity statically reachable by fuzzers

2969/3329

Functions covered at runtime

275

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: magic_fuzzer_fd

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	505	45.0%
gold	[1:9]	30	2.67%
yellow	[10:29]	24	2.13%
greenyellow	[30:49]	7	0.62%
lawngreen	50+	556	49.5%
All colors	1122	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
2755	2875	11 : View List ['handle_mime', 'readlink', 'file_error', 'stat', 'gnu_dev_minor', 'lstat', 'gnu_dev_major', 'strerror', 'magic_file', 'bad_link', '__errno_location']	2755	2875	file_fsmagic	call site	/src/file/src/fsmagic.c:117
703	703	2 : View List ['apprentice_load', 'file_magwarn']	957	965	apprentice_1	call site	/src/file/src/apprentice.c:498
350	350	1 : View List ['cdf_check_summary_info']	350	418	file_trycdf	call site	/src/file/src/readcdf.c:640
176	176	1 : View List ['apprentice_list']	176	176	apprentice_1	call site	/src/file/src/apprentice.c:518
125	125	2 : View List ['mdebug', 'file_mdump']	127	2252	mget	call site	/src/file/src/softmagic.c:1798
92	92	1 : View List ['file_pipe2file']	94	1498	file_tryelf	call site	/src/file/src/readelf.c:1854
84	84	1 : View List ['apprentice_compile']	779	779	apprentice_1	call site	/src/file/src/apprentice.c:489
62	62	1 : View List ['cdf_read_sector_chain']	62	62	cdf_read_user_stream	call site	/src/file/src/cdf.c:868
50	72	2 : View List ['sread', 'unreadable_info']	52	2345	file_or_fd	call site	/src/file/src/magic.c:496
44	55	4 : View List ['regerror', 'strlen', 'file_magerror', 'file_printable']	44	55	file_regcomp	call site	/src/file/src/funcs.c:712
40	40	1 : View List ['file_oomem']	53	53	apprentice_map	call site	/src/file/src/apprentice.c:3274
40	40	1 : View List ['mlist_free_one']	40	40	mlist_free	call site	/src/file/src/apprentice.c:677

Runtime coverage analysis

Covered functions

200

Functions that are reachable but not covered

134

Reachable functions

302

Percentage of reachable functions covered

55.63%

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
magic_fuzzer_fd.cc	1
fuzzer_temp_file.h	5
filemagic.c	5
filefuncs.c	33
filefsmagic.c	3
filecompress.c	21
filebuffer.c	3
fileencoding.c	10
fileis_tar.c	3
fileis_json.c	11
fileis_csv.c	3
filereadcdf.c	9
filecdf.c	40
/usr/include/x86_64-linux-gnu/bits/byteswap.h	3
filecdf_time.c	5
filereadelf.c	9
filestrlcpy.c	1
filesoftmagic.c	29
fileapprentice.c	6
fileprint.c	7
fileder.c	6
filefmtcheck.c	4
fileascmagic.c	4

Fuzzer: magic_fuzzer_loaddb

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	148	31.1%
gold	[1:9]	1	0.21%
yellow	[10:29]	2	0.42%
greenyellow	[30:49]	2	0.42%
lawngreen	50+	322	67.7%
All colors	475	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
176	176	1 : View List ['apprentice_list']	176	176	apprentice_1	call site	/src/file/src/apprentice.c:518
86	246	7 : View List ['file_error', 'fstat', 'maxoff_t', 'mmap', 'mprotect', 'check_buffer', '__errno_location']	90	261	apprentice_map	call site	/src/file/src/apprentice.c:3284
40	40	1 : View List ['file_oomem']	42	53	apprentice_map	call site	/src/file/src/apprentice.c:3274
40	40	1 : View List ['file_oomem']	40	40	parse	call site	/src/file/src/apprentice.c:2061
40	40	1 : View List ['file_oomem']	40	40	parse	call site	/src/file/src/apprentice.c:2076
40	40	1 : View List ['file_oomem']	40	40	addentry	call site	/src/file/src/apprentice.c:1289
40	40	1 : View List ['file_oomem']	40	40	coalesce_entries	call site	/src/file/src/apprentice.c:1475
40	40	1 : View List ['file_oomem']	40	40	file_check_mem	call site	/src/file/src/funcs.c:616
20	20	2 : View List ['get_default_magic', 'getenv']	20	20	magic_getpath	call site	/src/file/src/magic.c:256
4	4	1 : View List ['__errno_location']	4	44	load_1	call site	/src/file/src/apprentice.c:1319
4	4	2 : View List ['abort', 'close']	4	4	fuzzer_get_tmpfile(unsignedcharconst*,unsignedlong)	call site	/src/fuzzer_temp_file.h:47
2	378	4 : View List ['check_format', 'getvalue', '__ctype_b_loc', 'file_mdump']	2	386	parse	call site	/src/file/src/apprentice.c:2344

Runtime coverage analysis

Covered functions

93

Functions that are reachable but not covered

69

Reachable functions

153

Percentage of reachable functions covered

54.9%

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
magic_fuzzer_loaddb.cc	1
fuzzer_temp_file.h	5
filemagic.c	7
fileapprentice.c	53
filefuncs.c	17
fileprint.c	7
filecdf_time.c	4
filestrlcpy.c	1
fileencoding.c	1
/usr/include/x86_64-linux-gnu/bits/byteswap.h	3

Fuzzer: magic_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	437	42.0%
gold	[1:9]	24	2.30%
yellow	[10:29]	21	2.02%
greenyellow	[30:49]	11	1.05%
lawngreen	50+	546	52.5%
All colors	1039	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
703	703	2 : View List ['apprentice_load', 'file_magwarn']	957	965	apprentice_1	call site	/src/file/src/apprentice.c:498
176	176	1 : View List ['apprentice_list']	176	176	apprentice_1	call site	/src/file/src/apprentice.c:518
176	176	3 : View List ['cdf_tole2', 'cdf_app_to_mime', 'cdf_file_catalog_info']	176	176	cdf_check_summary_info	call site	/src/file/src/readcdf.c:405
125	125	2 : View List ['mdebug', 'file_mdump']	127	2252	mget	call site	/src/file/src/softmagic.c:1798
84	84	1 : View List ['apprentice_compile']	779	779	apprentice_1	call site	/src/file/src/apprentice.c:489
44	55	4 : View List ['regerror', 'strlen', 'file_magerror', 'file_printable']	44	55	file_regcomp	call site	/src/file/src/funcs.c:712
40	47	2 : View List ['file_magerror', 'buffer_init']	40	47	msetoffset	call site	/src/file/src/softmagic.c:1518
40	40	1 : View List ['file_oomem']	53	53	apprentice_map	call site	/src/file/src/apprentice.c:3274
40	40	1 : View List ['mlist_free_one']	40	40	mlist_free	call site	/src/file/src/apprentice.c:677
40	40	1 : View List ['file_oomem']	40	40	file_ascmagic_with_encoding	call site	/src/file/src/ascmagic.c:146
40	40	1 : View List ['file_oomem']	40	40	file_encoding	call site	/src/file/src/encoding.c:153
40	40	1 : View List ['file_oomem']	40	40	file_getbuffer	call site	/src/file/src/funcs.c:550

Runtime coverage analysis

Covered functions

192

Functions that are reachable but not covered

107

Reachable functions

277

Percentage of reachable functions covered

61.37%

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
magic_fuzzer.cc	1
filemagic.c	1
filefuncs.c	33
filebuffer.c	3
fileencoding.c	10
filecompress.c	21
fileis_tar.c	3
fileis_json.c	11
fileis_csv.c	3
filereadcdf.c	9
filecdf.c	40
/usr/include/x86_64-linux-gnu/bits/byteswap.h	3
filecdf_time.c	5
filereadelf.c	9
filestrlcpy.c	1
filesoftmagic.c	29
fileapprentice.c	6
fileprint.c	7
fileder.c	6
filefmtcheck.c	4
fileascmagic.c	4

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
do_os_note	/src/file/src/readelf.c	9	['struct.magic_set *', 'char *', 'int ', 'int ', 'int ', 'int ', 'size_t ', 'size_t ', 'int *']	6	0	532	95	39	13	0	118	76
do_core_note	/src/file/src/readelf.c	11	['struct.magic_set *', 'char *', 'int ', 'int ', 'int ', 'int ', 'size_t ', 'size_t ', 'int *', 'size_t ', 'int ']	6	0	921	149	52	14	0	108	52
do_auxv_note	/src/file/src/readelf.c	15	['struct.magic_set *', 'char *', 'int ', 'int ', 'int ', 'int ', 'size_t ', 'size_t ', 'int *', 'size_t ', 'int ', 'int ', 'size_t ', 'int ', 'size_t ']	7	0	350	48	13	13	0	85	43

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

Functions statically reachable by fuzzers

388/432

Cyclomatic complexity statically reachable by fuzzers

3140 / 3329

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

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
file_apprentice	77	38	49.35%	['magic_fuzzer_loaddb']
apprentice_1	56	26	46.42%	['magic_fuzzer_loaddb']
mkdbname	41	21	51.21%	['magic_fuzzer_loaddb']
apprentice_map	73	34	46.57%	['magic_fuzzer_loaddb']
check_buffer	53	28	52.83%	['magic_fuzzer_loaddb']
sread	62	27	43.54%	['magic_fuzzer_fd', 'magic_fuzzer']
uncompressbuf	170	81	47.64%	['magic_fuzzer_fd', 'magic_fuzzer']
get_next_format	43	23	53.48%	['magic_fuzzer_fd', 'magic_fuzzer']
get_next_format_from_precision	101	40	39.60%	['magic_fuzzer_fd', 'magic_fuzzer']
file_fsmagic	329	11	3.343%	['magic_fuzzer_fd']
file_checkfmt	33	18	54.54%	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
file_is_json	40	16	40.0%	['magic_fuzzer_fd', 'magic_fuzzer']
file_or_fd	124	42	33.87%	['magic_fuzzer_fd']
do_note_freebsd_version	73	33	45.20%	[]
cvt_flip	48	24	50.0%	['magic_fuzzer_fd', 'magic_fuzzer']
apprentice_load	120	44	36.66%	['magic_fuzzer_loaddb']
apprentice_magic_strength	54	26	48.14%	['magic_fuzzer_loaddb']
cdf_check_summary_info	42	12	28.57%	['magic_fuzzer_fd', 'magic_fuzzer']

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
	[]	[]
/usr/include/x86_64-linux-gnu/bits/byteswap.h	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	[]
/src/file/src/cdf_time.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
/src/file/src/softmagic.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/funcs.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
/src/file/src/is_csv.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/fmtcheck.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/magic_fuzzer_loaddb.cc	['magic_fuzzer_loaddb']	['magic_fuzzer_loaddb']
/src/file/src/print.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
/src/file/src/is_tar.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/der.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/encoding.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
/src/file/src/apprentice.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
/src/file/src/readcdf.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/compress.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/magic_fuzzer_fd.cc	['magic_fuzzer_fd']	['magic_fuzzer_fd']
/src/file/src/cdf.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/fsmagic.c	['magic_fuzzer_fd']	['magic_fuzzer_fd']
/src/file/src/ascmagic.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/fuzzer_temp_file.h	['magic_fuzzer_fd', 'magic_fuzzer_loaddb']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb']
/src/file/src/buffer.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/magic_fuzzer.cc	['magic_fuzzer']	['magic_fuzzer']
/src/file/src/magic.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']
/src/file/src/readelf.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd']
/src/file/src/is_json.c	['magic_fuzzer_fd', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer']
/src/file/src/strlcpy.c	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']	['magic_fuzzer_fd', 'magic_fuzzer_loaddb', 'magic_fuzzer']

Directories in report

Directory
/src/
/usr/include/x86_64-linux-gnu/bits/
/src/file/src/