High level conclusions

Fuzzers reach 56.09% code coverage.

Fuzzers reach 32.07% of cyclomatic complexity.

Fuzzers reach 32.01% of all functions.

Reachability and coverage overview

Functions statically reachable by fuzzers

210 / 656

Cyclomatic complexity statically reachable by fuzzers

818 / 2550

Runtime code coverage of functions

368 / 656

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	Fuzzers runtime hit	Func lines hit %	I Count	BB Count	Cyclomatic complexity	Functions reached	Reached by functions	Accumulated cyclomatic complexity	Undiscovered complexity

Fuzzer: dgif_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	3	3.61%
gold	[1:9]	2	2.40%
yellow	[10:29]	3	3.61%
greenyellow	[30:49]	2	2.40%
lawngreen	50+	73	87.9%
All colors	83	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	2	39	DGifOpen	call site: 00003	/src/giflib-code/dgif_lib.c:187
0	0	None	2	2	DGifCloseFile	call site: 00077	/src/giflib-code/dgif_lib.c:707
0	0	None	0	72	DGifGetImageHeader	call site: 00024	/src/giflib-code/dgif_lib.c:366
0	0	None	0	63	DGifGetImageDesc	call site: 00023	/src/giflib-code/dgif_lib.c:433
0	0	None	0	58	DGifGetLine	call site: 00046	/src/giflib-code/dgif_lib.c:487
0	0	None	0	58	DGifGetLine	call site: 00046	/src/giflib-code/dgif_lib.c:493
0	0	None	0	43	DGifGetScreenDesc	call site: 00007	/src/giflib-code/dgif_lib.c:254
0	0	None	0	16	DGifSlurp	call site: 00041	/src/giflib-code/dgif_lib.c:1204
0	0	None	0	16	DGifSlurp	call site: 00044	/src/giflib-code/dgif_lib.c:1211
0	0	None	0	15	DGifGetExtension	call site: 00062	/src/giflib-code/dgif_lib.c:572
0	0	None	0	5	DGifGetRecordType	call site: 00021	/src/giflib-code/dgif_lib.c:329
0	0	None	0	0	DGifOpen	call site: 00002	/src/giflib-code/dgif_lib.c:173

Runtime coverage analysis

Covered functions

31

Functions that are reachable but not covered

6

Reachable functions

39

Percentage of reachable functions covered

84.62%

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
/src/dgif_target.cc	1
/src/dgif_fuzz_common.cc	2
/src/giflib-code/dgif_lib.c	21
/src/giflib-code/gifalloc.c	6
/src/giflib-code/openbsd-reallocarray.c	1

Fuzzer: egif_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	21	25.3%
gold	[1:9]	0	0.0%
yellow	[10:29]	0	0.0%
greenyellow	[30:49]	0	0.0%
lawngreen	50+	62	74.6%
All colors	83	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
2	2	1 : View List ['fwrite']	2	2	InternalWrite	call site: 00028	/src/giflib-code/egif_lib.c:262
0	14	2 : View List ['GifFreeMapObject', 'GifMakeMapObject']	0	92	EGifPutImageDesc	call site: 00043	/src/giflib-code/egif_lib.c:390
0	5	1 : View List ['InternalWrite']	0	36	EGifPutImageDesc	call site: 00051	/src/giflib-code/egif_lib.c:419
0	0	None	124	472	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:43
0	0	None	124	461	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:62
0	0	None	124	458	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:71
0	0	None	31	57	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:131
0	0	None	31	57	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:148
0	0	None	31	57	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:168
0	0	None	31	34	rgb_to_gif(unsignedcharconst*,unsignedlong)	call site: 00000	/src/egif_fuzz_common.cc:105
0	0	None	4	59	EGifPutScreenDesc	call site: 00025	/src/giflib-code/egif_lib.c:286
0	0	None	2	13	EGifCloseFile	call site: 00038	/src/giflib-code/egif_lib.c:770

Runtime coverage analysis

Covered functions

28

Functions that are reachable but not covered

10

Reachable functions

41

Percentage of reachable functions covered

75.61%

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
/src/egif_target.cc	1
/src/egif_fuzz_common.cc	3
/src/giflib-code/gifalloc.c	3
/src/giflib-code/quantize.c	3
/src/giflib-code/egif_lib.c	13
/src/giflib-code/gif_hash.c	5
/src/giflib-code/qprintf.c	1
/src/giflib-code/gif_err.c	1

Fuzzer: dgif_protobuf_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	39	11.5%
gold	[1:9]	2	0.59%
yellow	[10:29]	5	1.47%
greenyellow	[30:49]	1	0.29%
lawngreen	50+	291	86.0%
All colors	338	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
7	15	3 : View List ['gifProtoFuzzer::GlobalColorTable::_internal_colors() const', 'void google::protobuf::internal::ArenaStringPtr::Set<>(std::__1::basic_string , std::__1::allocator > const&, google::protobuf::Arena*)', 'google::protobuf::MessageLite::GetArena() const']	11	19	gifProtoFuzzer::GlobalColorTable::MergeImpl(google::protobuf::MessageLite&,google::protobuf::MessageLiteconst&)	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:1295
7	15	3 : View List ['gifProtoFuzzer::LocalColorTable::_internal_colors() const', 'void google::protobuf::internal::ArenaStringPtr::Set<>(std::__1::basic_string , std::__1::allocator > const&, google::protobuf::Arena*)', 'google::protobuf::MessageLite::GetArena() const']	11	19	gifProtoFuzzer::LocalColorTable::MergeImpl(google::protobuf::MessageLite&,google::protobuf::MessageLiteconst&)	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:2494
6	6	1 : View List ['google::protobuf::internal::ArenaStringPtr::ClearNonDefaultToEmpty()']	8	8	gifProtoFuzzer::LocalColorTable::Clear()	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:2421
0	0	3 : View List ['std::__1::basic_ofstream >::basic_ofstream(char const*, unsigned int)', 'std::__1::basic_ostream >::write(char const*, long)', 'std::__1::basic_ofstream >::~basic_ofstream()']	4	235	TestOneProtoInput(gifProtoFuzzer::GifProtoconst&)	call site: 00000	/src/dgif_protobuf_target.cc:19
0	0	None	4	4	gifProtoFuzzer::LogicalScreenDescriptor::MergeImpl(google::protobuf::MessageLite&,google::protobuf::MessageLiteconst&)	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:1027
0	0	None	4	4	gifProtoFuzzer::ImageDescriptor::MergeImpl(google::protobuf::MessageLite&,google::protobuf::MessageLiteconst&)	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:1628
0	0	None	4	4	gifProtoFuzzer::ImageData::MergeImpl(google::protobuf::MessageLite&,google::protobuf::MessageLiteconst&)	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:3065
0	0	None	4	4	gifProtoFuzzer::Header::MergeImpl(google::protobuf::MessageLite&,google::protobuf::MessageLiteconst&)	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:4235
0	0	None	2	39	DGifOpen	call site: 00226	/src/giflib-code/dgif_lib.c:187
0	0	None	2	2	gifProtoFuzzer::ImageDescriptor::Clear()	call site: 00000	/src/genfiles/gif_fuzz_proto.pb.cc:1491
0	0	None	2	2	DGifCloseFile	call site: 00300	/src/giflib-code/dgif_lib.c:707
0	0	None	0	72	DGifGetImageHeader	call site: 00247	/src/giflib-code/dgif_lib.c:366

Runtime coverage analysis

Covered functions

251

Functions that are reachable but not covered

96

Reachable functions

356

Percentage of reachable functions covered

73.03%

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
/src/dgif_protobuf_target.cc	2
/src/genfiles/gif_fuzz_proto.pb.h	82
/src/genfiles/gif_fuzz_proto.pb.cc	10
/src/LPM/external.protobuf/include/google/protobuf/message.h	2
/src/LPM/external.protobuf/include/google/protobuf/message_lite.h	4
/src/LPM/external.protobuf/include/google/protobuf/metadata_lite.h	2
/src/LPM/external.protobuf/include/google/protobuf/internal_visibility.h	1
/src/LPM/external.protobuf/include/google/protobuf/repeated_ptr_field.h	28
/src/./ProtoToGif.h	2
/src/ProtoToGif.cpp	22
/src/LPM/external.protobuf/include/google/protobuf/arenastring.h	2
/src/dgif_fuzz_common.cc	2
/src/giflib-code/dgif_lib.c	21
/src/giflib-code/gifalloc.c	6
/src/giflib-code/openbsd-reallocarray.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
gifProtoFuzzer::GifProto::CopyFrom(gifProtoFuzzer::GifProtoconst&)	/src/genfiles/gif_fuzz_proto.pb.cc	2	['N/A', 'N/A']	15	0	32	6	3	236	0	538	500
gifProtoFuzzer::ImageChunk::CopyFrom(gifProtoFuzzer::ImageChunkconst&)	/src/genfiles/gif_fuzz_proto.pb.cc	2	['N/A', 'N/A']	16	0	32	6	3	234	0	504	158
gifProtoFuzzer::GifProto::IsInitializedImpl(google::protobuf::MessageLiteconst&)	/src/genfiles/gif_fuzz_proto.pb.cc	1	['N/A']	9	0	152	23	10	118	0	169	145
gifProtoFuzzer::GifProto::ByteSizeLong()const	/src/genfiles/gif_fuzz_proto.pb.cc	1	['N/A']	8	0	199	22	8	188	0	247	144
gifProtoFuzzer::GifProto::GifProto(google::protobuf::Arena*,gifProtoFuzzer::GifProtoconst&)	/src/genfiles/gif_fuzz_proto.pb.cc	3	['N/A', 'N/A', 'N/A']	18	0	315	38	37	178	0	486	46
fuzz_dgif_ala_android(unsignedcharconst*,unsignedlong)	/src/dgif_fuzz_common.cc	2	['N/A', 'size_t']	6	0	468	56	22	47	0	291	35

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

Functions statically reachable by fuzzers

440 / 656

Cyclomatic complexity statically reachable by fuzzers

1822 / 2550

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.

/src/dgif_target.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=['DGifGetImageDesc', 'DGifDecreaseImageCounter', 'DGifSlurp']

/src/egif_target.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=['stub_output_writer(GifFileType*, unsigned char const*, int)', 'EGifPutScreenDesc', 'EGifCompressOutput', 'EGifCompressLine', 'rgb_to_gif(unsigned char const*, unsigned long)', 'GifMakeMapObject', 'SubdivColorMap', 'EGifCloseFile', 'EGifPutImageDesc']

/src/dgif_protobuf_target.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=['gifProtoFuzzer::ProtoConverter::visit(gifProtoFuzzer::GifProto const&)', 'gifProtoFuzzer::ProtoConverter::visit(gifProtoFuzzer::GifProto const&)', 'gifProtoFuzzer::GifProto::SharedDtor(google::protobuf::MessageLite&)', 'gifProtoFuzzer::GifProto::GifProto(google::protobuf::Arena*)', 'gifProtoFuzzer::ProtoConverter::visit(gifProtoFuzzer::ImageData const&)', 'gifProtoFuzzer::GifProto::GifProto(google::protobuf::Arena*)', 'gifProtoFuzzer::GifProto::SharedCtor(google::protobuf::Arena*)', 'gifProtoFuzzer::ProtoConverter::visit(gifProtoFuzzer::ImageData const&)', 'gifProtoFuzzer::GifProto::SharedCtor(google::protobuf::Arena*)']

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
rgb_to_gif(unsignedcharconst*,unsignedlong)	86	39	45.34%	['egif_target']
EGifOpen	39	21	53.84%	['egif_target']
EGifGetGifVersion	31	10	32.25%	['egif_target']
EGifPutImageDesc	63	28	44.44%	['egif_target']

This section shows which files and directories are considered in this report. The main reason for showing this is fuzz introspector may include more code in the reasoning than is desired. This section helps identify if too many files/directories are included, e.g. third party code, which may be irrelevant for the threat model. In the event too much is included, fuzz introspector supports a configuration file that can exclude data from the report. See the following link for more information on how to create a config file: link

Files in report

Source file	Reached by	Covered by
	[]	[]
/usr/local/bin/../include/c++/v1/sstream	[]	[]
/src/giflib-code/gif_err.c	['egif_target']	[]
/src/LPM/external.protobuf/include/google/protobuf/repeated_ptr_field.h	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/LPM/external.protobuf/include/google/protobuf/internal_visibility.h	['dgif_protobuf_target']	[]
/src/giflib-code/quantize.c	['egif_target']	['egif_target']
/src/dgif_target.cc	['dgif_target']	['dgif_target']
/src/dgif_fuzz_common.cc	['dgif_target', 'dgif_protobuf_target']	['dgif_target', 'dgif_protobuf_target']
/src/giflib-code/dgif_lib.c	['dgif_target', 'dgif_protobuf_target']	['dgif_target', 'dgif_protobuf_target']
/src/LPM/external.protobuf/include/google/protobuf/arena_align.h	[]	[]
/src/dgif_protobuf_target.cc	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/./ProtoToGif.h	['dgif_protobuf_target']	[]
/src/LPM/external.protobuf/include/google/protobuf/arenastring.h	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/egif_target.cc	['egif_target']	['egif_target']
/src/LPM/external.protobuf/include/google/protobuf/message.h	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/giflib-code/gifalloc.c	['dgif_target', 'egif_target', 'dgif_protobuf_target']	['dgif_target', 'egif_target', 'dgif_protobuf_target']
/src/giflib-code/egif_lib.c	['egif_target']	['egif_target']
/src/LPM/external.protobuf/include/google/protobuf/message_lite.h	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/giflib-code/gif_hash.c	['egif_target']	['egif_target']
/src/genfiles/gif_fuzz_proto.pb.cc	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/LPM/external.protobuf/include/google/protobuf/generated_message_util.h	[]	[]
/src/LPM/external.protobuf/include/absl/log/internal/nullstream.h	[]	[]
/src/giflib-code/openbsd-reallocarray.c	['dgif_target', 'dgif_protobuf_target']	['dgif_target', 'dgif_protobuf_target']
/src/LPM/external.protobuf/include/google/protobuf/metadata_lite.h	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/giflib-code/gif_font.c	[]	[]
/src/LPM/external.protobuf/include/google/protobuf/port.h	[]	[]
/src/LPM/external.protobuf/include/google/protobuf/generated_message_bases.h	[]	[]
/src/egif_fuzz_common.cc	['egif_target']	['egif_target']
/src/LPM/external.protobuf/include/google/protobuf/wire_format_lite.h	[]	[]
/src/LPM/external.protobuf/include/absl/numeric/bits.h	[]	[]
/src/LPM/external.protobuf/include/google/protobuf/arena.h	[]	[]
/src/LPM/external.protobuf/include/google/protobuf/io/coded_stream.h	[]	[]
/src/giflib-code/qprintf.c	['egif_target']	[]
/src/genfiles/gif_fuzz_proto.pb.h	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/ProtoToGif.cpp	['dgif_protobuf_target']	['dgif_protobuf_target']
/src/LPM/external.protobuf/include/google/protobuf/unknown_field_set.h	[]	[]

Directories in report

Directory
/src/
/src/genfiles/
/src/giflib-code/
/src/LPM/external.protobuf/include/absl/numeric/
/src/LPM/external.protobuf/include/absl/log/internal/
/usr/local/bin/../include/c++/v1/
/src/./
/src/LPM/external.protobuf/include/google/protobuf/
/src/LPM/external.protobuf/include/google/protobuf/io/