High level conclusions

Fuzzers reach 66.06% code coverage.

Fuzzers reach 75.47% of cyclomatic complexity.

Fuzzers reach 67.27% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

111 / 165

Cyclomatic complexity statically reachable by fuzzers

1197 / 1586

Runtime code coverage of functions

109 / 165

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: checksum_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	7	15.5%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	38	84.4%
All colors	45	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
14	14	2 : View List ['byte_swap', 'crc_word_big']	14	14	crc32_z	call site: 00002	/src/zlib/crc32.c:731
0	0	None	0	0	adler32_combine_	call site: 00043	/src/zlib/adler32.c:139

Runtime coverage analysis

Covered functions

15

Functions that are reachable but not covered

3

Reachable functions

18

Percentage of reachable functions covered

83.33%

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
checksum_fuzzer.c	1
zlib/crc32.c	12
zlib/adler32.c	4

Fuzzer: zlib_uncompress_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	24	47.0%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	2	3.92%
lawngreen	50+	25	49.0%
All colors	51	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
252	474	6 : View List ['crc32', 'fixedtables', 'updatewindow', 'inflate_fast', 'adler32', 'inflate_table']	252	474	inflate	call site: 00037	/src/zlib/inflate.c:817
0	0	None	252	474	inflate	call site: 00012	/src/zlib/inflate.c:623
0	0	None	252	474	inflate	call site: 00012	/src/zlib/inflate.c:629
0	0	None	252	474	inflate	call site: 00027	/src/zlib/inflate.c:638
0	0	None	252	474	inflate	call site: 00027	/src/zlib/inflate.c:656
0	0	None	252	474	inflate	call site: 00043	/src/zlib/inflate.c:1137
0	0	None	21	46	inflate	call site: 00039	/src/zlib/inflate.c:847
0	0	None	0	369	uncompress2	call site: 00002	/src/zlib/uncompr.c:36
0	0	None	0	15	inflateReset2	call site: 00006	/src/zlib/inflate.c:150
0	0	None	0	15	inflateReset2	call site: 00006	/src/zlib/inflate.c:167
0	0	None	0	12	uncompress2	call site: 00011	/src/zlib/uncompr.c:70
0	0	None	0	0	adler32_z	call site: 00029	/src/zlib/adler32.c:72

Runtime coverage analysis

Covered functions

22

Functions that are reachable but not covered

5

Reachable functions

22

Percentage of reachable functions covered

77.27%

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
zlib_uncompress_fuzzer.cc	1
zlib/uncompr.c	2
zlib/inflate.c	10
zlib/crc32.c	5
zlib/adler32.c	2
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: zlib_uncompress2_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	24	48.0%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	2	4.0%
lawngreen	50+	24	48.0%
All colors	50	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
252	474	6 : View List ['crc32', 'fixedtables', 'updatewindow', 'inflate_fast', 'adler32', 'inflate_table']	252	474	inflate	call site: 00036	/src/zlib/inflate.c:817
0	0	None	252	474	inflate	call site: 00011	/src/zlib/inflate.c:623
0	0	None	252	474	inflate	call site: 00011	/src/zlib/inflate.c:629
0	0	None	252	474	inflate	call site: 00026	/src/zlib/inflate.c:638
0	0	None	252	474	inflate	call site: 00026	/src/zlib/inflate.c:656
0	0	None	252	474	inflate	call site: 00042	/src/zlib/inflate.c:1137
0	0	None	21	46	inflate	call site: 00038	/src/zlib/inflate.c:847
0	0	None	0	369	uncompress2	call site: 00001	/src/zlib/uncompr.c:36
0	0	None	0	15	inflateReset2	call site: 00005	/src/zlib/inflate.c:150
0	0	None	0	15	inflateReset2	call site: 00005	/src/zlib/inflate.c:167
0	0	None	0	12	uncompress2	call site: 00010	/src/zlib/uncompr.c:70
0	0	None	0	0	adler32_z	call site: 00028	/src/zlib/adler32.c:72

Runtime coverage analysis

Covered functions

21

Functions that are reachable but not covered

5

Reachable functions

21

Percentage of reachable functions covered

76.19%

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
zlib_uncompress2_fuzzer.cc	1
zlib/uncompr.c	1
zlib/inflate.c	10
zlib/crc32.c	5
zlib/adler32.c	2
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: example_small_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	71	44.6%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	88	55.3%
All colors	159	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
21	21	1 : View List ['crc32']	579	630	deflate	call site: 00054	/src/zlib/deflate.c:1160
21	21	1 : View List ['crc32']	21	21	read_buf	call site: 00062	/src/zlib/deflate.c:227
0	21	1 : View List ['deflateEnd']	0	21	deflateInit2_	call site: 00006	/src/zlib/deflate.c:499
0	0	None	747	869	deflate	call site: 00035	/src/zlib/deflate.c:1009
0	0	None	747	869	deflate	call site: 00035	/src/zlib/deflate.c:1011
0	0	None	747	869	deflate	call site: 00035	/src/zlib/deflate.c:1013
0	0	None	747	867	deflate	call site: 00038	/src/zlib/deflate.c:1024
0	0	None	747	838	deflate	call site: 00042	/src/zlib/deflate.c:1039
0	0	None	705	786	deflate	call site: 00045	/src/zlib/deflate.c:1090
0	0	None	663	734	deflate	call site: 00048	/src/zlib/deflate.c:1117
0	0	None	621	682	deflate	call site: 00051	/src/zlib/deflate.c:1139
0	0	None	288	474	inflate	call site: 00130	/src/zlib/inflate.c:623

Runtime coverage analysis

Covered functions

53

Functions that are reachable but not covered

13

Reachable functions

62

Percentage of reachable functions covered

79.03%

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
example_small_fuzzer.c	3
zlib/compress.c	1
zlib/deflate.c	16
zlib/crc32.c	5
zlib/adler32.c	2
zlib/trees.c	20
zlib/inflate.c	10
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: example_large_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	68	40.7%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	99	59.2%
All colors	167	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
21	21	1 : View List ['crc32']	472	630	deflate	call site: 00053	/src/zlib/deflate.c:1160
21	21	1 : View List ['crc32']	21	21	read_buf	call site: 00061	/src/zlib/deflate.c:227
7	7	1 : View List ['_tr_align']	7	31	deflate	call site: 00098	/src/zlib/deflate.c:1212
0	21	1 : View List ['deflateEnd']	0	21	deflateInit2_	call site: 00005	/src/zlib/deflate.c:499
0	17	2 : View List ['_tr_stored_block', 'flush_pending']	0	17	deflate_stored	call site: 00064	/src/zlib/deflate.c:1800
0	7	1 : View List ['_tr_stored_block']	0	14	_tr_flush_block	call site: 00081	/src/zlib/trees.c:1047
0	0	None	640	879	deflate	call site: 00033	/src/zlib/deflate.c:974
0	0	None	640	869	deflate	call site: 00034	/src/zlib/deflate.c:1009
0	0	None	640	869	deflate	call site: 00034	/src/zlib/deflate.c:1011
0	0	None	640	869	deflate	call site: 00034	/src/zlib/deflate.c:1013
0	0	None	640	867	deflate	call site: 00037	/src/zlib/deflate.c:1024
0	0	None	640	838	deflate	call site: 00041	/src/zlib/deflate.c:1039

Runtime coverage analysis

Covered functions

55

Functions that are reachable but not covered

10

Reachable functions

61

Percentage of reachable functions covered

83.61%

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
example_large_fuzzer.c	3
zlib/deflate.c	17
zlib/crc32.c	5
zlib/adler32.c	2
zlib/trees.c	20
zlib/inflate.c	10
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: compress_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	65	41.6%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	91	58.3%
All colors	156	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
21	21	1 : View List ['crc32']	472	630	deflate	call site: 00054	/src/zlib/deflate.c:1160
21	21	1 : View List ['crc32']	21	21	read_buf	call site: 00062	/src/zlib/deflate.c:227
7	14	2 : View List ['_tr_stored_block', '_tr_align']	7	38	deflate	call site: 00099	/src/zlib/deflate.c:1211
0	59	3 : View List ['_tr_stored_block', 'read_buf', 'flush_pending']	0	59	deflate_stored	call site: 00062	/src/zlib/deflate.c:1757
0	21	1 : View List ['deflateEnd']	0	21	deflateInit2_	call site: 00007	/src/zlib/deflate.c:499
0	0	None	640	879	deflate	call site: 00034	/src/zlib/deflate.c:974
0	0	None	640	867	deflate	call site: 00038	/src/zlib/deflate.c:1024
0	0	None	640	838	deflate	call site: 00042	/src/zlib/deflate.c:1039
0	0	None	598	786	deflate	call site: 00045	/src/zlib/deflate.c:1090
0	0	None	556	734	deflate	call site: 00048	/src/zlib/deflate.c:1117
0	0	None	514	682	deflate	call site: 00051	/src/zlib/deflate.c:1139
0	0	None	252	474	inflate	call site: 00126	/src/zlib/inflate.c:623

Runtime coverage analysis

Covered functions

63

Functions that are reachable but not covered

11

Reachable functions

66

Percentage of reachable functions covered

83.33%

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
compress_fuzzer.c	4
zlib/compress.c	2
zlib/deflate.c	16
zlib/crc32.c	5
zlib/adler32.c	2
zlib/trees.c	20
zlib/uncompr.c	2
zlib/inflate.c	10
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: example_flush_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	73	44.2%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	92	55.7%
All colors	165	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
21	21	1 : View List ['crc32']	579	630	deflate	call site: 00054	/src/zlib/deflate.c:1160
21	21	1 : View List ['crc32']	21	21	read_buf	call site: 00062	/src/zlib/deflate.c:227
10	10	1 : View List ['updatewindow']	31	46	inflate	call site: 00149	/src/zlib/inflate.c:1244
7	7	1 : View List ['_tr_align']	7	31	deflate	call site: 00099	/src/zlib/deflate.c:1212
0	21	1 : View List ['deflateEnd']	0	21	deflateInit2_	call site: 00006	/src/zlib/deflate.c:499
0	0	None	747	879	deflate	call site: 00034	/src/zlib/deflate.c:974
0	0	None	747	869	deflate	call site: 00035	/src/zlib/deflate.c:1009
0	0	None	747	869	deflate	call site: 00035	/src/zlib/deflate.c:1011
0	0	None	747	869	deflate	call site: 00035	/src/zlib/deflate.c:1013
0	0	None	747	867	deflate	call site: 00038	/src/zlib/deflate.c:1024
0	0	None	747	838	deflate	call site: 00042	/src/zlib/deflate.c:1039
0	0	None	705	786	deflate	call site: 00045	/src/zlib/deflate.c:1090

Runtime coverage analysis

Covered functions

55

Functions that are reachable but not covered

12

Reachable functions

63

Percentage of reachable functions covered

80.95%

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
example_flush_fuzzer.c	3
zlib/compress.c	1
zlib/deflate.c	16
zlib/crc32.c	5
zlib/adler32.c	2
zlib/trees.c	20
zlib/inflate.c	12
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: example_dict_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	60	35.5%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	109	64.4%
All colors	169	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
21	21	1 : View List ['crc32']	135	630	deflate	call site: 00063	/src/zlib/deflate.c:1160
7	14	2 : View List ['_tr_stored_block', '_tr_align']	7	38	deflate	call site: 00104	/src/zlib/deflate.c:1211
0	21	1 : View List ['deflateEnd']	0	21	deflateInit2_	call site: 00002	/src/zlib/deflate.c:499
0	0	None	303	879	deflate	call site: 00043	/src/zlib/deflate.c:974
0	0	None	303	838	deflate	call site: 00051	/src/zlib/deflate.c:1039
0	0	None	261	786	deflate	call site: 00054	/src/zlib/deflate.c:1090
0	0	None	252	474	inflate	call site: 00134	/src/zlib/inflate.c:623
0	0	None	252	474	inflate	call site: 00134	/src/zlib/inflate.c:629
0	0	None	252	474	inflate	call site: 00136	/src/zlib/inflate.c:638
0	0	None	252	474	inflate	call site: 00136	/src/zlib/inflate.c:640
0	0	None	252	474	inflate	call site: 00136	/src/zlib/inflate.c:649
0	0	None	252	474	inflate	call site: 00136	/src/zlib/inflate.c:656

Runtime coverage analysis

Covered functions

58

Functions that are reachable but not covered

10

Reachable functions

63

Percentage of reachable functions covered

84.13%

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
example_dict_fuzzer.c	3
zlib/deflate.c	17
zlib/crc32.c	5
zlib/adler32.c	2
zlib/trees.c	20
zlib/inflate.c	11
zlib/inftrees.c	1
zlib/inffast.c	1

Fuzzer: minigzip_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	98	37.9%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	160	62.0%
All colors	258	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
510	510	1 : View List ['gz_zero']	512	1048	gzclose_w	call site: 00168	/src/zlib/gzwrite.c:609
510	510	1 : View List ['gz_zero']	510	2016	gz_write	call site: 00033	/src/zlib/gzwrite.c:185
423	423	1 : View List ['gz_skip']	423	1230	gz_read	call site: 00189	/src/zlib/gzread.c:277
15	15	1 : View List ['adler32']	139	869	deflate	call site: 00075	/src/zlib/deflate.c:1004
15	15	1 : View List ['adler32']	15	15	read_buf	call site: 00102	/src/zlib/deflate.c:227
14	14	2 : View List ['byte_swap', 'crc_word_big']	14	14	crc32_z	call site: 00043	/src/zlib/crc32.c:731
8	8	2 : View List ['malloc', 'strlen']	8	8	gz_error	call site: 00022	/src/zlib/gzlib.c:546
7	14	2 : View List ['_tr_stored_block', '_tr_align']	11	38	deflate	call site: 00139	/src/zlib/deflate.c:1211
4	17	3 : View List ['__errno_location', 'gz_error', 'strerror']	4	17	gz_load	call site: 00204	/src/zlib/gzread.c:27
4	4	1 : View List ['putShortMSB']	4	14	deflate	call site: 00150	/src/zlib/deflate.c:1241
2	2	1 : View List ['perror']	2	2	file_compress	call site: 00012	/src/minigzip_fuzzer.c:385
2	2	1 : View List ['perror']	2	2	file_uncompress	call site: 00184	/src/minigzip_fuzzer.c:434

Runtime coverage analysis

Covered functions

73

Functions that are reachable but not covered

31

Reachable functions

100

Percentage of reachable functions covered

69.0%

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
minigzip_fuzzer.c	6
zlib/gzlib.c	5
zlib/gzwrite.c	6
zlib/deflate.c	15
zlib/crc32.c	5
zlib/adler32.c	2
zlib/trees.c	20
zlib/gzclose.c	1
zlib/gzread.c	9
zlib/inflate.c	9
zlib/inftrees.c	1
zlib/inffast.c	1

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
deflate_slow	/src/zlib/deflate.c	2	['N/A', 'int']	5	0	1022	92	34	29	0	255	56

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

Functions statically reachable by fuzzers

113 / 165

Cyclomatic complexity statically reachable by fuzzers

1253 / 1586

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 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.

checksum_fuzzer.c

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=['crc32_z']

zlib_uncompress_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=['inflate', 'adler32']

zlib_uncompress2_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=['inflate', 'adler32']

example_small_fuzzer.c

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=['deflate', 'deflateResetKeep', 'inflate', '_tr_flush_block', 'read_buf', '_tr_stored_block']

example_large_fuzzer.c

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=['deflate', 'deflateResetKeep', 'inflate', '_tr_flush_block', 'deflate_stored', 'deflateInit_']

compress_fuzzer.c

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=['deflate', 'deflateResetKeep', 'inflate', '_tr_flush_block', 'read_buf', 'deflateInit_']

example_flush_fuzzer.c

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=['deflate', 'deflateResetKeep', 'inflate', '_tr_flush_block', 'read_buf', '_tr_stored_block']

example_dict_fuzzer.c

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=['deflate', 'deflateResetKeep', 'inflate', 'deflate_rle', '_tr_stored_block', 'deflate_huff', 'test_dict_deflate', 'read_buf']

minigzip_fuzzer.c

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=['deflate', 'deflate_rle', 'inflate', 'crc32_z', '_tr_flush_bits', 'gz_comp', 'gz_reset', 'deflateReset', '_tr_stored_block', 'read_buf']

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
deflate	257	132	51.36%	['example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']
deflateBound	48	20	41.66%	['example_dict_fuzzer']
gz_look	52	26	50.0%	['minigzip_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
	[]	[]
/src/zlib/adler32.c	['checksum_fuzzer', 'zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['checksum_fuzzer', 'zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer']
/src/zlib/compress.c	['example_small_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer']	['example_small_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer']
/src/zlib/gzwrite.c	['minigzip_fuzzer']	['minigzip_fuzzer']
/src/zlib/gzclose.c	['minigzip_fuzzer']	['minigzip_fuzzer']
/src/example_flush_fuzzer.c	['example_flush_fuzzer']	['example_flush_fuzzer']
/src/zlib/gzread.c	['minigzip_fuzzer']	['minigzip_fuzzer']
/src/zlib/deflate.c	['example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']
/src/minigzip_fuzzer.c	['minigzip_fuzzer']	['minigzip_fuzzer']
/src/zlib/inftrees.c	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']
/src/zlib/uncompr.c	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'compress_fuzzer']	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'compress_fuzzer']
/src/zlib_uncompress_fuzzer.cc	['zlib_uncompress_fuzzer']	['zlib_uncompress_fuzzer']
/src/zlib/inflate.c	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']
/src/zlib/gzlib.c	['minigzip_fuzzer']	['minigzip_fuzzer']
/src/example_small_fuzzer.c	['example_small_fuzzer']	['example_small_fuzzer']
/src/zlib/trees.c	['example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']
/src/zlib_uncompress2_fuzzer.cc	['zlib_uncompress2_fuzzer']	['zlib_uncompress2_fuzzer']
/src/zlib/inffast.c	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']
/src/example_large_fuzzer.c	['example_large_fuzzer']	['example_large_fuzzer']
/src/zlib/zutil.c	[]	[]
/src/example_dict_fuzzer.c	['example_dict_fuzzer']	['example_dict_fuzzer']
/src/checksum_fuzzer.c	['checksum_fuzzer']	['checksum_fuzzer']
/src/zlib/crc32.c	['checksum_fuzzer', 'zlib_uncompress_fuzzer', 'zlib_uncompress2_fuzzer', 'example_small_fuzzer', 'example_large_fuzzer', 'compress_fuzzer', 'example_flush_fuzzer', 'example_dict_fuzzer', 'minigzip_fuzzer']	['checksum_fuzzer', 'minigzip_fuzzer']
/src/compress_fuzzer.c	['compress_fuzzer']	['compress_fuzzer']

Directories in report

Directory
/src/zlib/
/src/