High level conclusions

Fuzzers reach 56.74% code coverage.

Fuzzers reach 0.829% of cyclomatic complexity.

Fuzzers reach 0.859% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

16 / 1861

Cyclomatic complexity statically reachable by fuzzers

29 / 3498

Runtime code coverage of functions

1056 / 1861

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: fuzzfuzz_http

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	1836	98.4%
gold	[1:9]	5	0.26%
yellow	[10:29]	5	0.26%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	19	1.01%
All colors	1865	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
539	575	PathAndQuery::empty	call site: 00575	single_stream_send_extra_large_body_multi_frames_one_buffer
525	1162	Store::new	call site: 01162	recv_invalid_push_promise_headers_is_stream_protocol_error
436	123	std::str::from_utf8	call site: 00123	recv_invalid_push_promise_headers_is_stream_protocol_error
149	1690	Table::new	call site: 01690	rst_stream_max
95	24	Table::new	call site: 00024	single_stream_send_extra_large_body_multi_frames_one_buffer
37	1115	Recv::new	call site: 01115	FlowControl::inc_window
15	2	Request::builder	call site: 00002	Codec::with_max_recv_frame_size
11	560	Pos::is_some	call site: 00560	if_downcast_into
10	1853	StatusCode::from_bytes	call site: 01853	Frame::map
7	1154	Prioritize::new	call site: 01154
5	18	FramedWrite::new	call site: 00018	Encoder::new
3	1840	StatusCode::from_bytes	call site: 01840	HeaderName::as_ref

Runtime coverage analysis

Covered functions

180

Functions that are reachable but not covered

23

Reachable functions

34

Percentage of reachable functions covered

32.35%

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
http/fuzzfuzz_http.rs	7
httprequest.rs	13
h2/tests/h2-supportmock.rs	89
h2/tests/h2-tests/tests/server.rs	61
h2client.rs	13
h2codec/mod.rs	13
h2/tests/h2-tests/tests/stream_states.rs	71
httpconvert.rs	6
h2/tests/h2-tests/tests/prioritization.rs	23
h2server.rs	19
h2codec/framed_read.rs	7
h2proto/error.rs	2
h2/tests/h2-supportassert.rs	5
h2/tests/h2-supportutil.rs	13
h2ext.rs	7
httpbyte_str.rs	2
httpheader/value.rs	1
h2/tests/h2-tests/tests/flow_control.rs	26
h2frame/mod.rs	3
h2/tests/h2-supportframes.rs	20
h2/tests/h2-tests/tests/codec_read.rs	3
h2/tests/h2-supportraw.rs	4
h2/tests/h2-tests/tests/push_promise.rs	38
h2hpack/decoder.rs	8
h2proto/streams/store.rs	6
h2frame/headers.rs	7
httpheader/map.rs	15
h2hpack/header.rs	2
h2/tests/h2-supportfuture_ext.rs	14
h2lib.rs	1
h2proto/streams/streams.rs	6
h2/tests/h2-fuzzmain.rs	31
h2/tests/h2-tests/tests/client_request.rs	29
httpuri/builder.rs	2
h2share.rs	10
h2proto/connection.rs	9
h2proto/settings.rs	3
h2/tests/h2-supportclient_ext.rs	7
h2hpack/encoder.rs	1
h2proto/streams/prioritize.rs	2
h2frame/settings.rs	2
h2proto/streams/flow_control.rs	11
h2proto/streams/recv.rs	10
h2/tests/h2-tests/tests/ping_pong.rs	31
h2proto/ping_pong.rs	8
h2hpack/table.rs	1
http/tests/status_code.rs	7

Fuzzer: fuzz_hpack

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	1947	88.9%
gold	[1:9]	2	0.09%
yellow	[10:29]	6	0.27%
greenyellow	[30:49]	3	0.13%
lawngreen	50+	230	10.5%
All colors	2188	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
804	1021	take	call site: 01021	rst_stream_max
744	269	HeaderName::as_str	call site: 00269	single_stream_send_extra_large_body_multi_frames_one_buffer
180	83	h2::frame::BytesStr::try_from	call site: 00083	srv_window_update_on_lower_stream_id
56	18	Encoder::new	call site: 00018	single_stream_send_extra_large_body_multi_frames_one_buffer
14	3	h2::fuzz_bridge::fuzz_logic::fuzz_hpack	call site: 00003	Encoder::new
13	1846	Decoder::decode_indexed	call site: 01846
13	2116	Name::into_entry	call site: 02116	Decoder::decode_literal
12	1884	Decoder::try_decode_string	call site: 01884	Frame::map
10	1984	StatusCode::from_bytes	call site: 01984	Frame::map
9	2017	parse_hdr	call site: 02017	Store::try_for_each
9	2133	Table::set_max_size	call site: 02133	Deque::push_back
7	1831	h2::fuzz_bridge::fuzz_logic::fuzz_hpack	call site: 01831	Representation::load

Runtime coverage analysis

Covered functions

211

Functions that are reachable but not covered

1

Reachable functions

2

Percentage of reachable functions covered

50.0%

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
h2/fuzz/fuzz_targets/fuzz_hpack.rs	2
h2fuzz_bridge.rs	11
h2/tests/h2-supportmock.rs	104
h2client.rs	13
h2codec/mod.rs	13
h2/tests/h2-tests/tests/server.rs	56
h2/tests/h2-tests/tests/stream_states.rs	71
httpconvert.rs	6
h2/tests/h2-tests/tests/prioritization.rs	23
h2/tests/h2-supportassert.rs	5
h2/tests/h2-supportutil.rs	13
h2ext.rs	8
httpbyte_str.rs	2
httpheader/value.rs	6
h2/tests/h2-tests/tests/flow_control.rs	26
httprequest.rs	13
h2codec/framed_read.rs	7
h2proto/error.rs	2
h2frame/mod.rs	3
h2/tests/h2-supportframes.rs	20
h2/tests/h2-tests/tests/codec_read.rs	5
h2/tests/h2-supportraw.rs	4
h2/tests/h2-tests/tests/push_promise.rs	38
h2hpack/decoder.rs	35
h2proto/streams/store.rs	12
h2frame/headers.rs	7
httpheader/map.rs	14
h2hpack/header.rs	17
h2/tests/h2-supportfuture_ext.rs	14
h2lib.rs	1
h2proto/connection.rs	9
h2proto/settings.rs	3
h2/tests/h2-supportclient_ext.rs	7
h2proto/streams/streams.rs	6
h2server.rs	19
h2/tests/h2-tests/tests/client_request.rs	29
h2proto/streams/flow_control.rs	11
h2frame/settings.rs	2
h2proto/streams/recv.rs	10
h2hpack/encoder.rs	17
h2proto/streams/prioritize.rs	3
h2/tests/h2-fuzzmain.rs	31
httpuri/builder.rs	2
h2share.rs	10
h2/tests/h2-tests/tests/ping_pong.rs	31
h2proto/ping_pong.rs	8
h2hpack/table.rs	1
httpextensions.rs	2
http/tests/status_code.rs	14
httpmethod.rs	4
httpheader/name.rs	22
h2proto/streams/buffer.rs	2

Fuzzer: fuzz_client

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	1754	95.0%
gold	[1:9]	5	0.27%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	86	4.66%
All colors	1845	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
392	1316	frame::Headers::new	call site: 01316	recv_invalid_push_promise_headers_is_stream_protocol_error
210	1104	PathAndQuery::empty	call site: 01104	srv_window_update_on_lower_stream_id
172	275	calculate_headermap_size	call site: 00275	recv_invalid_push_promise_headers_is_stream_protocol_error
155	90	Request::builder	call site: 00090	srv_window_update_on_lower_stream_id
123	811	C::o::n::n::e::c::t::i::o::n::::::::n::e::w::streams_config	call site: 00811	srv_window_update_on_lower_stream_id
122	625	Codec::framed_write	call site: 00625	single_stream_send_extra_large_body_multi_frames_one_buffer
101	458	StreamRef::clone_to_opaque	call site: 00458	recv_invalid_push_promise_headers_is_stream_protocol_error
90	1010	Pos::is_some	call site: 01010	Handle::assert_client_handshake
80	1764	calc_max_continuation_frames	call site: 01764	rst_stream_max
61	563	SendRequest::send_request	call site: 00563	srv_window_update_on_lower_stream_id
55	940	Settings::new	call site: 00940	Handle::assert_client_handshake
52	21	mock::new	call site: 00021	single_stream_send_extra_large_body_multi_frames_one_buffer

Runtime coverage analysis

Covered functions

1361

Functions that are reachable but not covered

22

Reachable functions

35

Percentage of reachable functions covered

37.14%

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
h2/fuzz/fuzz_targets/fuzz_client.rs	12
h2/tests/h2-supportmock.rs	89
h2client.rs	13
h2codec/mod.rs	13
h2/tests/h2-tests/tests/server.rs	61
h2/tests/h2-tests/tests/stream_states.rs	71
httpconvert.rs	6
h2/tests/h2-tests/tests/prioritization.rs	23
h2/tests/h2-supportassert.rs	5
h2/tests/h2-supportutil.rs	13
h2ext.rs	7
httpbyte_str.rs	2
httpheader/value.rs	1
h2/tests/h2-tests/tests/flow_control.rs	26
httprequest.rs	13
h2codec/framed_read.rs	7
h2proto/error.rs	2
h2frame/mod.rs	3
h2/tests/h2-supportframes.rs	20
h2/tests/h2-tests/tests/codec_read.rs	3
h2/tests/h2-supportraw.rs	4
h2/tests/h2-tests/tests/push_promise.rs	38
h2hpack/decoder.rs	8
h2proto/streams/store.rs	6
h2frame/headers.rs	7
httpheader/map.rs	15
h2hpack/header.rs	2
h2/tests/h2-supportfuture_ext.rs	14
h2lib.rs	1
h2proto/connection.rs	9
h2proto/settings.rs	3
h2/tests/h2-supportclient_ext.rs	7
h2proto/streams/streams.rs	6
h2server.rs	19
h2/tests/h2-tests/tests/client_request.rs	29
h2proto/streams/flow_control.rs	11
h2frame/settings.rs	2
h2proto/streams/recv.rs	10
h2hpack/encoder.rs	1
h2proto/streams/prioritize.rs	2
h2/tests/h2-fuzzmain.rs	31
httpuri/builder.rs	2
h2share.rs	10
h2/tests/h2-tests/tests/ping_pong.rs	31
h2proto/ping_pong.rs	8
h2hpack/table.rs	1

Fuzzer: fuzz_e2e

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	1678	91.8%
gold	[1:9]	3	0.16%
yellow	[10:29]	9	0.49%
greenyellow	[30:49]	1	0.05%
lawngreen	50+	136	7.44%
All colors	1827	100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked	Calltree index	Parent function	Callsite	Largest blocked function
203	1111	Result::map_err	call site: 01111	srv_window_update_on_lower_stream_id
172	275	calculate_headermap_size	call site: 00275	recv_invalid_push_promise_headers_is_stream_protocol_error
154	1554	Poll::map_err	call site: 01554	recv_invalid_push_promise_headers_is_stream_protocol_error
123	811	C::o::n::n::e::c::t::i::o::n::::::::n::e::w::streams_config	call site: 00811	srv_window_update_on_lower_stream_id
121	626	Codec::set_max_send_frame_size	call site: 00626	single_stream_send_extra_large_body_multi_frames_one_buffer
117	1316	frame::Headers::new	call site: 01316	recv_invalid_push_promise_headers_is_stream_protocol_error
114	1435	MockIo::poll_flush	call site: 01435	reset_new_stream_before_send
101	458	StreamRef::clone_to_opaque	call site: 00458	recv_invalid_push_promise_headers_is_stream_protocol_error
72	155	frame::Settings::ack	call site: 00155	srv_window_update_on_lower_stream_id
62	1764	calc_max_continuation_frames	call site: 01764	rst_stream_max
60	563	SendRequest::send_request	call site: 00563	srv_window_update_on_lower_stream_id
55	940	Settings::new	call site: 00940	Handle::assert_client_handshake

Runtime coverage analysis

Covered functions

2126

Functions that are reachable but not covered

19

Reachable functions

48

Percentage of reachable functions covered

60.42%

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
h2/fuzz/fuzz_targets/fuzz_e2e.rs	4
h2/tests/h2-supportmock.rs	89
h2client.rs	13
h2codec/mod.rs	13
h2/tests/h2-tests/tests/server.rs	56
h2/tests/h2-tests/tests/stream_states.rs	71
httpconvert.rs	6
h2/tests/h2-tests/tests/prioritization.rs	23
h2/tests/h2-supportassert.rs	5
h2/tests/h2-supportutil.rs	13
h2ext.rs	7
httpbyte_str.rs	2
httpheader/value.rs	1
h2/tests/h2-tests/tests/flow_control.rs	26
httprequest.rs	13
h2codec/framed_read.rs	7
h2proto/error.rs	2
h2frame/mod.rs	3
h2/tests/h2-supportframes.rs	20
h2/tests/h2-tests/tests/codec_read.rs	3
h2/tests/h2-supportraw.rs	4
h2/tests/h2-tests/tests/push_promise.rs	38
h2hpack/decoder.rs	8
h2proto/streams/store.rs	6
h2frame/headers.rs	7
httpheader/map.rs	14
h2hpack/header.rs	2
h2/tests/h2-supportfuture_ext.rs	14
h2lib.rs	1
h2proto/connection.rs	9
h2proto/settings.rs	3
h2/tests/h2-supportclient_ext.rs	7
h2proto/streams/streams.rs	6
h2server.rs	19
h2/tests/h2-tests/tests/client_request.rs	29
h2proto/streams/flow_control.rs	11
h2frame/settings.rs	2
h2proto/streams/recv.rs	10
h2hpack/encoder.rs	1
h2proto/streams/prioritize.rs	2
h2/tests/h2-fuzzmain.rs	31
httpuri/builder.rs	2
h2share.rs	10
h2/tests/h2-tests/tests/ping_pong.rs	31
h2proto/ping_pong.rs	8
h2hpack/table.rs	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

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

Functions statically reachable by fuzzers

16 / 1861

Cyclomatic complexity statically reachable by fuzzers

29 / 3498

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.

http/fuzzfuzz_http.rs

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=['PathAndQuery::empty', 'Store::new', 'std::str::from_utf8', 'fuzz_target', 'Table::new', 'Recv::new', 'Request::builder', 'Pos::is_some', 'StatusCode::from_bytes', 'Prioritize::new']

h2/fuzz/fuzz_targets/fuzz_hpack.rs

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=['take', 'HeaderName::as_str', 'h2::frame::BytesStr::try_from', 'Encoder::new', 'h2::fuzz_bridge::fuzz_logic::fuzz_hpack', 'Decoder::decode_indexed', 'Name::into_entry', 'Decoder::try_decode_string', 'StatusCode::from_bytes', 'parse_hdr']

h2/fuzz/fuzz_targets/fuzz_client.rs

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=['frame::Headers::new', 'PathAndQuery::empty', 'calculate_headermap_size', 'Request::builder', 'C::o::n::n::e::c::t::i::o::n::::::::n::e::w::streams_config', 'Codec::framed_write', 'StreamRef::clone_to_opaque', 'Pos::is_some', 'calc_max_continuation_frames', 'SendRequest::send_request']

h2/fuzz/fuzz_targets/fuzz_e2e.rs

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=['Result::map_err', 'calculate_headermap_size', 'Poll::map_err', 'C::o::n::n::e::c::t::i::o::n::::::::n::e::w::streams_config', 'Codec::set_max_send_frame_size', 'frame::Headers::new', 'MockIo::poll_flush', 'StreamRef::clone_to_opaque', 'frame::Settings::ack', 'calc_max_continuation_frames']

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
h2::hpack::encoder::Encoder::encode_header	34	17	50.0%
h2::hpack::table::index_static	79	13	16.45%
parking_lot_core::parking_lot::park::parking_lot::raw_mutex::RawMutex::lock_slow::{closure:#0}, parking_lot::raw_mutex::RawMutex::lock_slow::{closure:#1}, parking_lot::raw_mutex::RawMutex::lock_slow::{closure:#2}::{closure:#0}	79	35	44.30%
parking_lot_core::parking_lot::park::parking_lot::condvar::Condvar::wait_until_internal::{closure:#0}, parking_lot::condvar::Condvar::wait_until_internal::{closure:#1}, parking_lot::condvar::Condvar::wait_until_internal::{closure:#2}::{closure:#0}	79	34	43.03%
tokio::runtime::blocking::pool::Spawner::spawn_task	53	24	45.28%
tokio::runtime::io::driver::Driver::turn	37	19	51.35%
tokio::runtime::scheduler::multi_thread::queue::Stealalloc::sync::Arctokio::runtime::scheduler::multi_thread::handle::Handle::steal_into	48	24	50.0%
tokio::runtime::scheduler::multi_thread::queue::Stealalloc::sync::Arctokio::runtime::scheduler::multi_thread::handle::Handle::steal_into2	78	17	21.79%
tokio::runtime::scheduler::multi_thread::worker::Core::next_task	51	10	19.60%
tokio::runtime::time::Driver::park_internal	36	18	50.0%
tokio::runtime::time::handle::Handle::process_at_time	37	17	45.94%
tokio::sync::notify::Notify::notify_waiters	56	10	17.85%
futures_core::task::__internal::atomic_waker::AtomicWaker::register	67	19	28.35%
h2::hpack::table::Table::index_occupied	42	13	30.95%
h2::proto::ping_pong::PingPong::send_pending_ping::fuzz_e2e::MockIo, h2::proto::streams::prioritize::Prioritizedbytes::bytes::Bytes	37	14	37.83%
h2::proto::streams::prioritize::Prioritize::reserve_capacity	47	18	38.29%
h2::proto::streams::state::State::recv_open	43	18	41.86%
h2::proto::streams::streams::Inner::recv_headers::bytes::bytes::Bytes::{closure:#0}	32	14	43.75%

New fuzzers

The below fuzzers are templates and suggestions for how to target the set of optimal functions above

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/h2/src/proto/ping_pong.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/src/hpack/test/fixture.rs	[]	[]
/src/h2/src/proto/streams/counts.rs	[]	[]
/src/h2/tests/h2-tests/tests/server.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/h2/tests/h2-support/src/raw.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/http/benches/src/header_name.rs	[]	[]
/src/h2/src/proto/streams/send.rs	[]	[]
/src/h2/src/hpack/table.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/src/hpack/encoder.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/error.rs	[]	[]
/src/http/src/response.rs	[]	[]
/src/h2/src/proto/streams/store.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/request.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/convert.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/h2/src/lib.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/h2/src/frame/mod.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_e2e']
/src/h2/src/client.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/tests/h2-tests/tests/hammer.rs	[]	[]
/src/h2/src/codec/framed_read.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/src/hpack/test/fuzz.rs	[]	[]
/src/h2/src/frame/stream_id.rs	[]	[]
/src/h2/src/proto/peer.rs	[]	[]
/src/http/benches/src/header_map/basic.rs	[]	[]
/src/h2/tests/h2-support/src/lib.rs	[]	[]
/src/h2/src/frame/reset.rs	[]	[]
/src/h2/src/proto/error.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_e2e']
/src/h2/tests/h2-tests/tests/prioritization.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/h2/src/frame/util.rs	[]	[]
/src/h2/src/hpack/header.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/src/hpack/decoder.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/header/value.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/tests/h2-support/src/prelude.rs	[]	[]
/src/http/src/header/map.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/src/proto/streams/stream.rs	[]	[]
/src/h2/tests/h2-support/src/util.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/h2/src/proto/connection.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/header/name.rs	['fuzz_hpack']	['fuzz_hpack']
/src/h2/src/frame/window_update.rs	[]	[]
/src/h2/tests/h2-tests/tests/flow_control.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/h2/fuzz/fuzz_targets/fuzz_client.rs	['fuzz_client']	['fuzz_client']
/src/h2/src/fuzz_bridge.rs	['fuzz_hpack']	['fuzz_hpack']
/src/h2/src/frame/priority.rs	[]	[]
/src/h2/src/proto/streams/recv.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/uri/mod.rs	[]	[]
/src/http/tests/header_map.rs	[]	[]
/src/h2/tests/h2-tests/tests/codec_read.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/h2/src/server.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/status.rs	[]	[]
/src/h2/fuzz/fuzz_targets/fuzz_hpack.rs	['fuzz_hpack']	[]
/src/h2/src/frame/settings.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/tests/h2-tests/tests/codec_write.rs	[]	[]
/src/h2/src/ext.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/fuzz/src/fuzz_http.rs	['fuzzfuzz_http']	[]
/src/http/src/byte_str.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/benches/src/method.rs	[]	[]
/src/http/tests/header_map_fuzz.rs	[]	[]
/src/http/benches/src/uri.rs	[]	[]
/src/http/benches/src/header_name2.rs	[]	[]
/src/h2/src/proto/streams/state.rs	[]	[]
/src/h2/src/codec/error.rs	[]	[]
/src/h2/src/frame/ping.rs	[]	[]
/src/h2/tests/h2-support/src/mock.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/fuzz/fuzz_targets/fuzz_e2e.rs	['fuzz_e2e']	['fuzz_e2e']
/src/h2/src/proto/go_away.rs	[]	[]
/src/h2/src/proto/streams/streams.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/method.rs	['fuzz_hpack']	['fuzz_hpack']
/src/h2/util/genhuff/src/main.rs	[]	[]
/src/h2/src/proto/streams/prioritize.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/src/proto/streams/buffer.rs	['fuzz_hpack']	['fuzz_hpack']
/src/h2/tests/h2-support/src/frames.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/benches/src/header_value.rs	[]	[]
/src/h2/src/frame/headers.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/uri/path.rs	[]	[]
/src/h2/tests/h2-tests/tests/client_request.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/h2/src/proto/settings.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/benches/src/header_map/vec_map.rs	[]	[]
/src/h2/src/frame/reason.rs	[]	[]
/src/http/util/src/main.rs	[]	[]
/src/h2/tests/h2-tests/tests/stream_states.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/h2/src/frame/data.rs	[]	[]
/src/h2/src/codec/mod.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/tests/status_code.rs	['fuzzfuzz_http', 'fuzz_hpack']	['fuzzfuzz_http', 'fuzz_hpack']
/src/http/src/uri/authority.rs	[]	[]
/src/h2/tests/h2-tests/tests/ping_pong.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/h2/src/frame/head.rs	[]	[]
/src/http/src/version.rs	[]	[]
/src/h2/src/proto/streams/flow_control.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/lib.rs	[]	[]
/src/h2/src/codec/framed_write.rs	[]	[]
/src/http/src/uri/scheme.rs	[]	[]
/src/h2/tests/h2-support/src/client_ext.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/http/src/extensions.rs	['fuzz_hpack']	['fuzz_hpack']
/src/h2/src/share.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/tests/h2-tests/tests/trailers.rs	[]	[]
/src/h2/src/error.rs	[]	[]
/src/http/src/uri/builder.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']
/src/h2/tests/h2-tests/tests/push_promise.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/http/src/uri/port.rs	[]	[]
/src/h2/tests/h2-support/src/assert.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	[]
/src/h2/src/frame/go_away.rs	[]	[]
/src/h2/tests/h2-support/src/future_ext.rs	['fuzzfuzz_http', 'fuzz_hpack', 'fuzz_client', 'fuzz_e2e']	['fuzz_client', 'fuzz_e2e']
/src/h2/src/hpack/huffman/mod.rs	[]	[]
/src/http/src/uri/tests.rs	[]	[]
/src/h2/tests/h2-support/src/trace.rs	[]	[]
/src/h2/benches/main.rs	[]	[]

Directories in report

Directory
/src/h2/fuzz/fuzz_targets/
/src/http/benches/src/header_map/
/src/h2/src/proto/
/src/http/src/
/src/h2/src/codec/
/src/http/fuzz/src/
/src/h2/tests/h2-support/src/
/src/h2/tests/h2-tests/tests/
/src/h2/src/
/src/h2/src/hpack/
/src/http/util/src/
/src/http/src/header/
/src/h2/util/genhuff/src/
/src/h2/src/hpack/test/
/src/h2/src/proto/streams/
/src/http/tests/
/src/h2/src/hpack/huffman/
/src/h2/src/frame/
/src/http/src/uri/
/src/http/benches/src/
/src/h2/benches/

This section shows a list of 3rd party function calls and their relative coverage information. By static analysis of the target project code, all of the 3rd party function call and their caller information, including the source file and line number that initiate the call are captured. The caller source code file and line number are shown in column 2 while column 1 is the function name of the 3rd party function call. Each occurrent of the 3rd party function call will occuply a separate row. Column 3 of each row indicate if the 3rd party call in the source file line is unreachable. Column 4 lists all fuzzers that have covered that particular system call in that specific location (source file and line)during their dynamic fuzzing.

Function in each files in report

Target sink	Callsite location	Reached by fuzzer	Covered by Fuzzers