High level conclusions

Fuzzers reach 12.41% of cyclomatic complexity.

Fuzzers reach 10.82% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

140 / 1293

Cyclomatic complexity statically reachable by fuzzers

973 / 7835

Runtime code coverage of functions

231 / 1293

Warning: The number of runtime covered functions are larger than the number of reachable functions. This means that Fuzz Introspector found there are more functions covered at runtime than what is considered reachable based on the static analysis. This is a limitation in the analysis as anything covered at runtime is by definition reachable by the fuzzers.
This is likely due to a limitation in the static analysis. In this case, the count of functions covered at runtime is the true value, which means this is what should be considered "achieved" by the fuzzer.

Use the project functions table below to query all functions that were not covered at runtime.

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	Runtime reached by Fuzzers	Combined 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: fuzz_http_h1p

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	21	38.1%
gold	[1:9]	2	3.63%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	32	58.1%
All colors	55	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
104	107	2 : View List ['nxt_log_start', 'nxt_process_arguments']	104	107	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:132
42	42	1 : View List ['nxt_lvlhsh_bucket_convertion_insert']	42	42	nxt_lvlhsh_level_convertion_insert	call site: 00000	/src/unit/src/nxt_lvlhsh.c:526
7	7	2 : View List ['nxt_thread_tid', 'gettimeofday']	7	9	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:94
6	6	3 : View List ['close', 'open64', 'read']	13	15	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:85
6	6	3 : View List ['close', 'open64', 'dup2']	6	6	nxt_stderr_start	call site: 00000	/src/unit/src/nxt_file.c:693
5	5	1 : View List ['nxt_thread_time_shared']	5	5	nxt_thread_time_update	call site: 00000	/src/unit/src/nxt_thread_time.c:52
0	0	None	14	101	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:71
0	0	None	0	105	nxt_mp_get_small	call site: 00026	/src/unit/src/nxt_mp.c:617
0	0	None	0	87	nxt_lvlhsh_bucket_insert	call site: 00000	/src/unit/src/nxt_lvlhsh.c:371
0	0	None	0	0	LLVMFuzzerInitialize	call site: 00000	/src/unit/fuzzing/nxt_http_h1p_fuzz.c:27
0	0	None	0	0	LLVMFuzzerInitialize	call site: 00000	/src/unit/fuzzing/nxt_http_h1p_fuzz.c:33
0	0	None	0	0	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:106

Runtime coverage analysis

Covered functions

79

Functions that are reachable but not covered

16

Reachable functions

40

Percentage of reachable functions covered

60.0%

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.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
fuzzing/nxt_http_h1p_fuzz.c	1
src/nxt_mp.c	9
src/nxt_malloc.c	4
src/nxt_log_moderation.c	1
src/nxt_thread_time.c	2
src/nxt_time.c	1
src/nxt_spinlock.c	2
src/nxt_timer.c	3
src/nxt_rbtree.c	6
src/nxt_http_parse.c	3
src/nxt_list.c	1
src/nxt_lvlhsh.c	3

Fuzzer: fuzz_basic

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	18	21.1%
gold	[1:9]	0	0.0%
yellow	[10:29]	3	3.52%
greenyellow	[30:49]	1	1.17%
lawngreen	50+	63	74.1%
All colors	85	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
104	107	2 : View List ['nxt_log_start', 'nxt_process_arguments']	104	107	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:132
7	7	2 : View List ['nxt_thread_tid', 'gettimeofday']	7	9	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:94
6	6	3 : View List ['close', 'open64', 'read']	13	15	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:85
6	6	3 : View List ['close', 'open64', 'dup2']	6	6	nxt_stderr_start	call site: 00000	/src/unit/src/nxt_file.c:693
5	5	1 : View List ['nxt_thread_time_shared']	5	5	nxt_thread_time_update	call site: 00000	/src/unit/src/nxt_thread_time.c:52
0	0	None	14	101	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:71
0	0	None	0	0	nxt_uri_fuzz	call site: 00046	/src/unit/fuzzing/nxt_basic_fuzz.c:170
0	0	None	0	0	nxt_websocket_base64_fuzz	call site: 00078	/src/unit/fuzzing/nxt_basic_fuzz.c:206
0	0	None	0	0	nxt_websocket_frame_fuzz	call site: 00081	/src/unit/fuzzing/nxt_basic_fuzz.c:225
0	0	None	0	0	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:106
0	0	None	0	0	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:79
0	0	None	0	0	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:99

Runtime coverage analysis

Covered functions

57

Functions that are reachable but not covered

17

Reachable functions

60

Percentage of reachable functions covered

71.67%

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
fuzzing/nxt_basic_fuzz.c	13
src/nxt_string.c	4
src/nxt_djb_hash.c	2
src/nxt_murmur_hash.c	2
src/nxt_parse.c	6
src/nxt_sha1.c	4
src/nxt_time_parse.c	2
src/nxt_malloc.c	3
src/nxt_log_moderation.c	1
src/nxt_thread_time.c	2
src/nxt_time.c	1
src/nxt_spinlock.c	2
src/nxt_timer.c	3
src/nxt_rbtree.c	4
src/nxt_utf8.c	4
src/nxt_websocket_accept.c	1
src/nxt_websocket.c	3

Fuzzer: fuzz_http_controller

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	22	41.5%
gold	[1:9]	2	3.77%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	29	54.7%
All colors	53	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
104	107	2 : View List ['nxt_log_start', 'nxt_process_arguments']	104	107	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:132
7	7	2 : View List ['nxt_thread_tid', 'gettimeofday']	7	9	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:94
6	6	3 : View List ['close', 'open64', 'read']	13	15	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:85
6	6	3 : View List ['close', 'open64', 'dup2']	6	6	nxt_stderr_start	call site: 00000	/src/unit/src/nxt_file.c:693
5	5	1 : View List ['nxt_thread_time_shared']	5	5	nxt_thread_time_update	call site: 00000	/src/unit/src/nxt_thread_time.c:52
0	0	None	14	101	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:71
0	0	None	0	105	nxt_mp_get_small	call site: 00026	/src/unit/src/nxt_mp.c:617
0	0	None	0	0	LLVMFuzzerInitialize	call site: 00000	/src/unit/fuzzing/nxt_http_h1p_fuzz.c:27
0	0	None	0	0	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:106
0	0	None	0	0	nxt_http_parse_complex_target	call site: 00000	/src/unit/src/nxt_http_parse.c:1062
0	0	None	0	0	nxt_http_parse_field_end	call site: 00000	/src/unit/src/nxt_http_parse.c:787
0	0	None	0	0	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:79

Runtime coverage analysis

Covered functions

62

Functions that are reachable but not covered

17

Reachable functions

40

Percentage of reachable functions covered

57.5%

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.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
fuzzing/nxt_http_controller_fuzz.c	1
src/nxt_mp.c	9
src/nxt_malloc.c	4
src/nxt_log_moderation.c	1
src/nxt_thread_time.c	2
src/nxt_time.c	1
src/nxt_spinlock.c	2
src/nxt_timer.c	3
src/nxt_rbtree.c	6
src/nxt_http_parse.c	3
src/nxt_list.c	1
src/nxt_lvlhsh.c	3

Fuzzer: fuzz_json

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	38	16.1%
gold	[1:9]	6	2.54%
yellow	[10:29]	2	0.84%
greenyellow	[30:49]	3	1.27%
lawngreen	50+	187	79.2%
All colors	236	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
104	107	2 : View List ['nxt_log_start', 'nxt_process_arguments']	104	107	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:132
7	7	2 : View List ['nxt_thread_tid', 'gettimeofday']	7	9	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:94
6	6	3 : View List ['close', 'open64', 'read']	13	15	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:85
6	6	3 : View List ['close', 'open64', 'dup2']	6	6	nxt_stderr_start	call site: 00000	/src/unit/src/nxt_file.c:693
5	5	1 : View List ['nxt_thread_time_shared']	5	5	nxt_thread_time_update	call site: 00000	/src/unit/src/nxt_thread_time.c:52
0	221	1 : View List ['nxt_conf_vldt_error']	0	221	nxt_conf_validate	call site: 00232	/src/unit/src/nxt_conf_validation.c:1554
0	221	1 : View List ['nxt_conf_vldt_error']	0	221	nxt_conf_vldt_if	call site: 00000	/src/unit/src/nxt_conf_validation.c:1757
0	124	1 : View List ['nxt_mp_alloc']	0	474	nxt_var_ref_get	call site: 00192	/src/unit/src/nxt_var.c:123
0	100	1 : View List ['nxt_mp_alloc_large']	0	100	nxt_mp_align	call site: 00000	/src/unit/src/nxt_mp.c:445
0	33	1 : View List ['nxt_conf_get_object_member']	0	254	nxt_conf_vldt_pass	call site: 00000	/src/unit/src/nxt_conf_validation.c:1988
0	25	2 : View List ['nxt_rbtree_delete', 'free']	0	25	nxt_mp_chunk_free	call site: 00198	/src/unit/src/nxt_mp.c:899
0	11	1 : View List ['nxt_conf_get_object_member']	0	232	nxt_conf_vldt_pass	call site: 00000	/src/unit/src/nxt_conf_validation.c:2023

Runtime coverage analysis

Covered functions

175

Functions that are reachable but not covered

24

Reachable functions

108

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.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
fuzzing/nxt_json_fuzz.c	1
src/nxt_mp.c	15
src/nxt_malloc.c	4
src/nxt_log_moderation.c	1
src/nxt_thread_time.c	2
src/nxt_time.c	1
src/nxt_spinlock.c	2
src/nxt_timer.c	3
src/nxt_rbtree.c	6
src/nxt_array.c	2
src/nxt_conf.c	18
src/nxt_utf8.c	1
src/nxt_djb_hash.c	1
src/nxt_lvlhsh.c	14
src/nxt_list.c	2
src/nxt_conf_validation.c	5
src/nxt_tstr.c	3
src/nxt_sprintf.c	4
src/nxt_var.c	5
src/nxt_http_variables.c	1
src/nxt_string.c	3
src/nxt_http_request.c	4

Fuzzer: fuzz_http_h1p_peer

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	21	35.5%
gold	[1:9]	2	3.38%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	36	61.0%
All colors	59	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
104	107	2 : View List ['nxt_log_start', 'nxt_process_arguments']	104	107	nxt_lib_start	call site: 00000	/src/unit/src/nxt_lib.c:132
42	42	1 : View List ['nxt_lvlhsh_bucket_convertion_insert']	42	42	nxt_lvlhsh_level_convertion_insert	call site: 00000	/src/unit/src/nxt_lvlhsh.c:526
7	7	2 : View List ['nxt_thread_tid', 'gettimeofday']	7	9	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:94
6	6	3 : View List ['close', 'open64', 'read']	13	15	nxt_random_stir	call site: 00000	/src/unit/src/nxt_random.c:85
6	6	3 : View List ['close', 'open64', 'dup2']	6	6	nxt_stderr_start	call site: 00000	/src/unit/src/nxt_file.c:693
5	5	1 : View List ['nxt_thread_time_shared']	5	5	nxt_thread_time_update	call site: 00000	/src/unit/src/nxt_thread_time.c:52
0	84	2 : View List ['nxt_lvlhsh_level_insert', 'nxt_lvlhsh_bucket_insert']	0	84	nxt_lvlhsh_level_insert	call site: 00000	/src/unit/src/nxt_lvlhsh.c:325
0	0	None	14	101	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:71
0	0	None	0	105	nxt_mp_get_small	call site: 00026	/src/unit/src/nxt_mp.c:617
0	0	None	0	87	nxt_lvlhsh_bucket_insert	call site: 00000	/src/unit/src/nxt_lvlhsh.c:371
0	0	None	0	0	LLVMFuzzerInitialize	call site: 00000	/src/unit/fuzzing/nxt_http_h1p_fuzz.c:27
0	0	None	0	0	nxt_strerror_start	call site: 00000	/src/unit/src/nxt_errno.c:106

Runtime coverage analysis

Covered functions

72

Functions that are reachable but not covered

16

Reachable functions

43

Percentage of reachable functions covered

62.79%

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.

Warning: The number of covered functions are larger than the number of reachable functions. This means that there are more functions covered at runtime than are extracted using static analysis. This is likely a result of the static analysis component failing to extract the right call graph or the coverage runtime being compiled with sanitizers in code that the static analysis has not analysed. This can happen if lto/gold is not used in all places that coverage instrumentation is used.

Function name	source code lines	source lines hit	percentage hit

Files reached

filename	functions hit
fuzzing/nxt_http_h1p_peer_fuzz.c	1
src/nxt_mp.c	12
src/nxt_malloc.c	4
src/nxt_log_moderation.c	1
src/nxt_thread_time.c	2
src/nxt_time.c	1
src/nxt_spinlock.c	2
src/nxt_timer.c	3
src/nxt_rbtree.c	6
src/nxt_http_parse.c	3
src/nxt_list.c	1
src/nxt_lvlhsh.c	3

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
nxt_router_conf_data_handler	/src/unit/src/nxt_router.c	2	['N/A', 'N/A']	33	0	345	33	11	426	0	2470	1746
nxt_http_application_handler	/src/unit/src/nxt_http_request.c	3	['N/A', 'N/A', 'N/A']	26	0	57	8	3	242	0	1409	532
nxt_runtime_create	/src/unit/src/nxt_runtime.c	1	['N/A']	22	0	285	35	17	331	0	1665	478
nxt_controller_process_new_port_handler	/src/unit/src/nxt_controller.c	2	['N/A', 'N/A']	29	0	47	9	4	275	0	1587	271
nxt_main_port_modules_handler	/src/unit/src/nxt_main_process.c	2	['N/A', 'N/A']	30	0	490	63	23	328	0	1652	230
nxt_http_parse_request_line	/src/unit/src/nxt_http_parse.c	3	['N/A', 'N/A', 'N/A']	16	0	1862	248	88	36	0	334	193
nxt_isolation_main_prefork	/src/unit/src/nxt_isolation.c	3	['N/A', 'N/A', 'N/A']	17	0	395	51	18	73	0	449	166
nxt_http_route_handler	/src/unit/src/nxt_http_route.c	3	['N/A', 'N/A', 'N/A']	22	0	213	29	9	109	0	674	150
nxt_http_static_send	/src/unit/src/nxt_http_static.c	3	['N/A', 'N/A', 'N/A']	26	0	1107	119	38	130	4	826	149
nxt_proto_setup	/src/unit/src/nxt_application.c	2	['N/A', 'N/A']	10	0	329	46	16	58	0	289	127

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

Functions statically reachable by fuzzers

691 / 1293

Cyclomatic complexity statically reachable by fuzzers

4761 / 7835

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	Runtime reached by Fuzzers	Combined 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.

fuzzing/nxt_http_h1p_fuzz.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=['nxt_zalloc', 'nxt_rbtree_insert', 'nxt_memalign', 'nxt_http_fields_process', 'nxt_lvlhsh_level_find']

fuzzing/nxt_basic_fuzz.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=['nxt_zalloc']

fuzzing/nxt_http_controller_fuzz.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=['nxt_zalloc', 'nxt_lvlhsh_find', 'nxt_rbtree_insert', 'nxt_memalign']

fuzzing/nxt_json_fuzz.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=['nxt_zalloc', 'nxt_conf_vldt_error', 'nxt_var_hash_find', 'nxt_lvlhsh_level_convertion_insert', 'nxt_rbtree_insert', 'nxt_memalign', 'nxt_lvlhsh_level_insert', 'nxt_rbtree_delete', 'nxt_conf_json_parse_string', 'nxt_conf_json_parse_number']

fuzzing/nxt_http_h1p_peer_fuzz.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=['nxt_zalloc', 'nxt_rbtree_insert', 'nxt_memalign', 'nxt_http_fields_process', 'nxt_lvlhsh_level_find']

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
nxt_conf_map_object	104	45	43.26%	['fuzz_json']
nxt_vsprintf	347	120	34.58%	['fuzz_json']

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/unit/src/nxt_http_parse.c	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_process.c	[]	[]
/src/unit/src/nxt_errno.c	[]	[]
/src/unit/src/nxt_http_chunk_parse.c	[]	[]
/src/unit/fuzzing/nxt_http_controller_fuzz.c	['fuzz_http_controller']	['fuzz_http_controller']
/src/unit/src/nxt_http_websocket.c	[]	[]
/src/unit/src/nxt_tstr.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_clone.c	[]	[]
/src/unit/src/nxt_app_nncq.h	[]	[]
/src/unit/src/nxt_log.c	[]	[]
/src/unit/src/nxt_random.c	[]	[]
/src/unit/src/nxt_string.c	['fuzz_basic', 'fuzz_json']	['fuzz_basic', 'fuzz_json']
/src/unit/src/nxt_conn_read.c	[]	[]
/src/unit/fuzzing/nxt_basic_fuzz.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_isolation.c	[]	[]
/src/unit/src/nxt_fs.c	[]	[]
/src/unit/fuzzing/nxt_json_fuzz.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_port_rpc.c	[]	[]
/src/unit/src/nxt_buf.c	[]	[]
/src/unit/src/nxt_event_engine.c	[]	[]
/src/unit/src/nxt_log_moderation.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	[]
/src/unit/src/nxt_port_memory.c	[]	[]
/src/unit/src/nxt_conn_connect.c	[]	[]
/src/unit/src/nxt_port.c	[]	[]
/src/unit/src/nxt_time_parse.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_router_access_log.c	[]	[]
/src/unit/src/nxt_lib.c	[]	[]
/src/unit/src/nxt_sha1.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_semaphore.c	[]	[]
/src/unit/src/nxt_thread_mutex.c	[]	[]
/src/unit/src/nxt_select_engine.c	[]	[]
/src/unit/src/nxt_unit_sptr.h	[]	[]
/src/unit/src/nxt_mp.c	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_nncq.h	[]	[]
/src/unit/src/nxt_http_static.c	[]	[]
/src/unit/src/nxt_thread_pool.c	[]	[]
/src/unit/src/nxt_murmur_hash.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_port_hash.c	[]	[]
/src/unit/src/nxt_poll_engine.c	[]	[]
/src/unit/src/nxt_time.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_router.c	[]	[]
/src/unit/src/nxt_mem_map.c	[]	[]
/src/unit/src/nxt_buf.h	[]	[]
/src/unit/src/nxt_socket.c	[]	[]
/src/unit/src/nxt_file_name.c	[]	[]
/src/unit/src/nxt_sendbuf.c	[]	[]
/src/unit/src/nxt_credential.c	[]	[]
/src/unit/src/nxt_main_process.c	[]	[]
/src/unit/src/nxt_fs_mount.c	[]	[]
/src/unit/src/nxt_process_title.c	[]	[]
/src/unit/src/nxt_signal.c	[]	[]
/src/unit/src/nxt_conf.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_file.c	[]	[]
/src/unit/src/nxt_timer.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	[]
/src/unit/src/nxt_listen_socket.c	[]	[]
/src/unit/src/nxt_djb_hash.c	['fuzz_basic', 'fuzz_json']	['fuzz_basic', 'fuzz_json']
/src/unit/src/nxt_conn_accept.c	[]	[]
/src/unit/fuzzing/nxt_http_h1p_peer_fuzz.c	['fuzz_http_h1p_peer']	['fuzz_http_h1p_peer']
/src/unit/src/nxt_controller.c	[]	[]
/src/unit/src/nxt_http_error.c	[]	[]
/src/unit/src/nxt_runtime.c	[]	[]
/src/unit/src/nxt_http_compression.c	[]	[]
/src/unit/src/nxt_service.c	[]	[]
/src/unit/src/nxt_http_variables.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_sockaddr.c	[]	[]
/src/unit/fuzzing/nxt_http_h1p_fuzz.c	['fuzz_http_h1p']	['fuzz_http_h1p']
/src/unit/src/nxt_rbtree.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_http_return.c	[]	[]
/src/unit/src/nxt_conn.c	[]	[]
/src/unit/src/nxt_var.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_spinlock.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_upstream.c	[]	[]
/src/unit/src/nxt_thread.c	[]	[]
/src/unit/src/nxt_capability.c	[]	[]
/src/unit/src/nxt_external.c	[]	[]
/src/unit/src/nxt_http_rewrite.c	[]	[]
/src/unit/src/nxt_sprintf.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_recvbuf.c	[]	[]
/src/unit/src/nxt_conf_validation.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_lvlhsh.c	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_utf8.c	['fuzz_basic', 'fuzz_json']	['fuzz_basic', 'fuzz_json']
/src/unit/src/nxt_linux_sendfile.c	[]	[]
/src/unit/src/nxt_gmtime.c	[]	[]
/src/unit/src/nxt_http_request.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_http_route_addr.c	[]	[]
/src/unit/src/nxt_upstream_round_robin.c	[]	[]
/src/unit/src/nxt_status.c	[]	[]
/src/unit/src/nxt_array.c	['fuzz_json']	['fuzz_json']
/src/unit/src/nxt_signal_handlers.c	[]	[]
/src/unit/src/nxt_parse.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_h1proto.c	[]	[]
/src/unit/src/nxt_conn_write.c	[]	[]
/src/unit/src/nxt_epoll_engine.c	[]	[]
/src/unit/src/nxt_socketpair.c	[]	[]
/src/unit/src/nxt_h1proto_websocket.c	[]	[]
/src/unit/src/nxt_malloc.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_conn_close.c	[]	[]
/src/unit/src/nxt_websocket_accept.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_http_proxy.c	[]	[]
/src/unit/src/nxt_socket_msg.c	[]	[]
/src/unit/src/nxt_websocket.c	['fuzz_basic']	['fuzz_basic']
/src/unit/src/nxt_list.c	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_port_socket.c	[]	[]
/src/unit/src/nxt_http_response.c	[]	[]
/src/unit/src/nxt_thread_time.c	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']	['fuzz_http_h1p', 'fuzz_basic', 'fuzz_http_controller', 'fuzz_json', 'fuzz_http_h1p_peer']
/src/unit/src/nxt_work_queue.c	[]	[]
/src/unit/src/nxt_http_route.c	[]	[]
/src/unit/src/nxt_application.c	[]	[]
/src/unit/src/nxt_http_set_headers.c	[]	[]

Directories in report

Directory
/src/unit/src/
/src/unit/fuzzing/