High level conclusions

Fuzzers reach 100.0% of cyclomatic complexity.

Fuzzers reach 100.0% of all functions.

Fuzzers reach 95.45% code coverage.

Reachability and coverage overview

Functions statically reachable by fuzzers

66 / 66

Cyclomatic complexity statically reachable by fuzzers

1112 / 1112

Runtime code coverage of functions

63 / 66

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: bzip2_decompress_target

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	9	23.0%
gold	[1:9]	1	2.56%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	29	74.3%
All colors	39	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
0	0	None	0	371	BZ2_bzDecompress	call site: 00018	/src/bzip2/bzlib.c:826
0	0	None	0	19	BZ2_decompress	call site: 00021	/src/bzip2/decompress.c:238
0	0	None	0	0	BZ2_bzDecompress	call site: 00021	/src/bzip2/bzlib.c:844
0	0	None	0	0	BZ2_bzBuffToBuffDecompress	call site: 00001	/src/bzip2/bzlib.c:1310
0	0	None	0	0	unRLE_obuf_to_output_FAST	call site: 00018	/src/bzip2/bzlib.c:666
0	0	None	0	0	BZ2_decompress	call site: 00024	/src/bzip2/decompress.c:512
0	0	None	0	0	BZ2_decompress	call site: 00024	/src/bzip2/decompress.c:519

Runtime coverage analysis

Covered functions

14

Functions that are reachable but not covered

4

Reachable functions

18

Percentage of reachable functions covered

77.78%

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
bzip2_decompress_target.c	1
bzip2/bzlib.c	12
bzip2/decompress.c	2
bzip2/huffman.c	1

Fuzzer: bzip2_compress_target

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	43	26.2%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	121	73.7%
All colors	164	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
0	0	None	63	226	sendMTFValues	call site: 00073	/src/bzip2/compress.c:261
0	0	None	54	217	sendMTFValues	call site: 00075	/src/bzip2/compress.c:302
0	0	None	54	217	sendMTFValues	call site: 00076	/src/bzip2/compress.c:436
0	0	None	27	109	mainSort	call site: 00038	/src/bzip2/blocksort.c:893
0	0	None	18	136	sendMTFValues	call site: 00089	/src/bzip2/compress.c:513
0	0	None	18	128	sendMTFValues	call site: 00094	/src/bzip2/compress.c:525
0	0	None	18	120	sendMTFValues	call site: 00099	/src/bzip2/compress.c:541
0	0	None	9	84	BZ2_blockSort	call site: 00036	/src/bzip2/blocksort.c:1069
0	0	None	9	84	BZ2_blockSort	call site: 00051	/src/bzip2/blocksort.c:1076
0	0	None	9	47	fallbackSort	call site: 00023	/src/bzip2/blocksort.c:229
0	0	None	9	47	fallbackSort	call site: 00024	/src/bzip2/blocksort.c:263
0	0	None	9	47	fallbackSort	call site: 00026	/src/bzip2/blocksort.c:308

Runtime coverage analysis

Covered functions

46

Functions that are reachable but not covered

6

Reachable functions

52

Percentage of reachable functions covered

88.46%

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
bzip2_compress_target.c	1
bzip2/bzlib.c	24
bzip2/compress.c	9
bzip2/blocksort.c	9
bzip2/huffman.c	3
bzip2/decompress.c	2

Fuzzer: bzip2_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	63	31.6%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	136	68.3%
All colors	199	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
960	960	1 : View List ['BZ2_bzWriteClose']	962	962	BZ2_bzclose	call site: 00187	/src/bzip2/bzlib.c:1521
6	407	4 : View List ['BZ2_bzDecompress', 'ferror', 'fread', 'myfeof']	6	407	BZ2_bzRead	call site: 00185	/src/bzip2/bzlib.c:1204
4	4	2 : View List ['strcmp', 'fopen']	6	111	bzopen_or_bzdopen	call site: 00000	/src/bzip2/bzlib.c:1420
2	2	1 : View List ['ungetc']	2	2	myfeof	call site: 00156	/src/bzip2/bzlib.c:909
2	2	1 : View List ['fclose']	2	2	bzopen_or_bzdopen	call site: 00000	/src/bzip2/bzlib.c:1446
0	57	1 : View List ['BZ2_bzWriteOpen']	2	59	bzopen_or_bzdopen	call site: 00000	/src/bzip2/bzlib.c:1436
0	11	1 : View List ['add_pair_to_block']	0	11	copy_input_until_stop	call site: 00031	/src/bzip2/bzlib.c:316
0	0	None	94	371	BZ2_bzDecompress	call site: 00160	/src/bzip2/bzlib.c:819
0	0	None	63	226	sendMTFValues	call site: 00088	/src/bzip2/compress.c:261
0	0	None	54	217	sendMTFValues	call site: 00090	/src/bzip2/compress.c:302
0	0	None	54	217	sendMTFValues	call site: 00091	/src/bzip2/compress.c:436
0	0	None	27	109	mainSort	call site: 00053	/src/bzip2/blocksort.c:893

Runtime coverage analysis

Covered functions

56

Functions that are reachable but not covered

28

Reachable functions

84

Percentage of reachable functions covered

66.67%

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
bzip2_fd.c	3
bzip2/bzlib.c	34
bzip2/compress.c	9
bzip2/blocksort.c	9
bzip2/huffman.c	3
bzip2/decompress.c	2

Fuzzer: bzip2_filename

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	55	26.5%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	152	73.4%
All colors	207	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
6	6	1 : View List ['BZ2_indexIntoF']	6	6	BZ2_decompress	call site: 00193	/src/bzip2/decompress.c:530
2	2	1 : View List ['fdopen']	4	109	bzopen_or_bzdopen	call site: 00155	/src/bzip2/bzlib.c:1420
2	2	1 : View List ['fclose']	2	2	bzopen_or_bzdopen	call site: 00160	/src/bzip2/bzlib.c:1446
0	57	1 : View List ['BZ2_bzWriteOpen']	2	59	bzopen_or_bzdopen	call site: 00158	/src/bzip2/bzlib.c:1436
0	11	1 : View List ['add_pair_to_block']	0	11	copy_input_until_stop	call site: 00029	/src/bzip2/bzlib.c:316
0	0	None	63	226	sendMTFValues	call site: 00087	/src/bzip2/compress.c:261
0	0	None	54	217	sendMTFValues	call site: 00089	/src/bzip2/compress.c:302
0	0	None	54	217	sendMTFValues	call site: 00090	/src/bzip2/compress.c:436
0	0	None	48	371	BZ2_bzDecompress	call site: 00174	/src/bzip2/bzlib.c:820
0	0	None	48	371	BZ2_bzDecompress	call site: 00186	/src/bzip2/bzlib.c:826
0	0	None	27	109	mainSort	call site: 00052	/src/bzip2/blocksort.c:893
0	0	None	18	136	sendMTFValues	call site: 00103	/src/bzip2/compress.c:513

Runtime coverage analysis

Covered functions

55

Functions that are reachable but not covered

23

Reachable functions

78

Percentage of reachable functions covered

70.51%

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
bzip2_filename.c	3
bzip2/bzlib.c	32
bzip2/compress.c	9
bzip2/blocksort.c	9
bzip2/huffman.c	3
bzip2/decompress.c	2

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

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

Functions statically reachable by fuzzers

66 / 66

Cyclomatic complexity statically reachable by fuzzers

1112 / 1112

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

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/bzip2_filename.c	['bzip2_filename']	['bzip2_filename']
/src/bzip2_decompress_target.c	['bzip2_decompress_target']	['bzip2_decompress_target']
/src/bzip2/bzlib.c	['bzip2_decompress_target', 'bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']	['bzip2_decompress_target', 'bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']
/src/bzip2/compress.c	['bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']	['bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']
/src/bzip2/blocksort.c	['bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']	['bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']
/src/bzip2/huffman.c	['bzip2_decompress_target', 'bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']	['bzip2_decompress_target', 'bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']
/src/bzip2_compress_target.c	['bzip2_compress_target']	['bzip2_compress_target']
/src/bzip2_fd.c	['bzip2_fd']	['bzip2_fd']
/src/bzip2/decompress.c	['bzip2_decompress_target', 'bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']	['bzip2_decompress_target', 'bzip2_compress_target', 'bzip2_fd', 'bzip2_filename']

Directories in report

Directory
/src/
/src/bzip2/