Fuzz introspector
For issues and ideas: https://github.com/ossf/fuzz-introspector/issues

Project functions overview

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 details

Fuzzer: ots-fuzzer

Call tree

The calltree shows the control flow of the fuzzer. This is overlaid with coverage information to display how much of the potential code a fuzzer can reach is in fact covered at runtime. In the following there is a link to a detailed calltree visualisation as well as a bitmap showing a high-level view of the calltree. For further information about these topics please see the glossary for full calltree and calltree overview

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 94 14.3%
gold [1:9] 35 5.33%
yellow [10:29] 17 2.59%
greenyellow [30:49] 12 1.82%
lawngreen 50+ 498 75.9%
All colors 656 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
15 168 inflate call site: 00168 crc32
9 185 adler32 call site: 00185 crc32
6 566 woff2::(anonymous namespace)::ReconstructTransformedHmtx(unsigned char const*, unsigned long, unsigned short, unsigned short, std::__1::vector > const&, unsigned int*, woff2::WOFF2Out*) call site: 00566
3 14 (anonymous namespace)::ProcessWOFF(ots::FontFile*, ots::Font*, ots::OTSStream*, unsigned char const*, unsigned long) call site: 00014 ntohl
3 437 ProcessCommands call site: 00437 SafeDecodeSymbol
2 32 (anonymous namespace)::ProcessWOFF(ots::FontFile*, ots::Font*, ots::OTSStream*, unsigned char const*, unsigned long) call site: 00032 fprintf
2 59 (anonymous namespace)::ProcessWOFF(ots::FontFile*, ots::Font*, ots::OTSStream*, unsigned char const*, unsigned long) call site: 00059 fprintf
2 62 (anonymous namespace)::ProcessWOFF(ots::FontFile*, ots::Font*, ots::OTSStream*, unsigned char const*, unsigned long) call site: 00062 fprintf
2 82 (anonymous namespace)::ProcessGeneric(ots::FontFile*, ots::Font*, unsigned int, ots::OTSStream*, unsigned char const*, unsigned long, std::__1::vector > const&, ots::Buffer&) call site: 00082 fprintf
2 90 (anonymous namespace)::GetTableAction(ots::FontFile const*, unsigned int) call site: 00090
2 288 (anonymous namespace)::ProcessGeneric(ots::FontFile*, ots::Font*, unsigned int, ots::OTSStream*, unsigned char const*, unsigned long, std::__1::vector > const&, ots::Buffer&) call site: 00288
2 302 (anonymous namespace)::ProcessGeneric(ots::FontFile*, ots::Font*, unsigned int, ots::OTSStream*, unsigned char const*, unsigned long, std::__1::vector > const&, ots::Buffer&) call site: 00302 fprintf

Runtime coverage analysis

Covered functions
680
Functions that are reachable but not covered
40
Reachable functions
394
Percentage of reachable functions covered
89.85%
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
/work/build/../../src/ots/util/ots-fuzzer.cc 3
/work/build/../../src/ots/include/opentype-sanitiser.h 10
/work/build/../../src/ots/include/ots-memory-stream.h 5
/work/build/../../src/ots/src/ots.cc 24
/work/build/../../src/ots/src/ots.h 16
/work/build/../../src/ots/src/avar.h 1
/work/build/../../src/ots/src/cff.h 2
/work/build/../../src/ots/src/cmap.h 1
/work/build/../../src/ots/src/colr.h 1
/work/build/../../src/ots/src/cpal.h 1
/work/build/../../src/ots/src/cvar.h 1
/work/build/../../src/ots/src/cvt.h 1
/work/build/../../src/ots/src/fpgm.h 1
/work/build/../../src/ots/src/fvar.h 2
/work/build/../../src/ots/src/gasp.h 1
/work/build/../../src/ots/src/gdef.h 1
/work/build/../../src/ots/src/glyf.h 1
/work/build/../../src/ots/src/gpos.h 1
/work/build/../../src/ots/src/layout.h 1
/work/build/../../src/ots/src/gsub.h 1
/work/build/../../src/ots/src/gvar.h 1
/work/build/../../src/ots/src/hdmx.h 1
/work/build/../../src/ots/src/head.h 1
/work/build/../../src/ots/src/hhea.h 1
/work/build/../../src/ots/src/metrics.h 2
/work/build/../../src/ots/src/hmtx.h 1
/work/build/../../src/ots/src/hvar.h 1
/work/build/../../src/ots/src/kern.h 1
/work/build/../../src/ots/src/loca.h 1
/work/build/../../src/ots/src/ltsh.h 1
/work/build/../../src/ots/src/math_.h 1
/work/build/../../src/ots/src/maxp.h 1
/work/build/../../src/ots/src/mvar.h 1
/work/build/../../src/ots/src/name.h 1
/work/build/../../src/ots/src/os2.h 1
/work/build/../../src/ots/src/post.h 1
/work/build/../../src/ots/src/prep.h 1
/work/build/../../src/ots/src/stat.h 1
/work/build/../../src/ots/src/vdmx.h 1
/work/build/../../src/ots/src/vhea.h 1
/work/build/../../src/ots/src/vmtx.h 1
/work/build/../../src/ots/src/vorg.h 1
/work/build/../../src/ots/src/vvar.h 1
/work/build/../../src/ots/src/feat.h 1
/work/build/../../src/ots/src/glat.h 1
/work/build/../../src/ots/src/gloc.h 1
/work/build/../../src/ots/src/sile.h 1
/work/build/../../src/ots/src/silf.h 1
/work/build/../../src/ots/src/sill.h 1
/work/build/../../src/ots/subprojects/zlib-1.3.1/uncompr.c 2
/work/build/../../src/ots/subprojects/zlib-1.3.1/inflate.c 10
/work/build/../../src/ots/subprojects/zlib-1.3.1/crc32.c 5
/work/build/../../src/ots/subprojects/zlib-1.3.1/adler32.c 2
/work/build/../../src/ots/subprojects/zlib-1.3.1/inftrees.c 1
/work/build/../../src/ots/subprojects/zlib-1.3.1/inffast.c 1
/work/build/../../src/ots/src/gvar.cc 1
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/woff2_dec.cc 26
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./buffer.h 10
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/woff2_out.cc 2
/work/build/../../src/ots/subprojects/woff2-1.0.2/include/woff2/output.h 4
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/variable_length.cc 2
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/woff2_common.cc 2
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./round.h 2
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./store_bytes.h 3
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/decode.c 36
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/state.c 5
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/bit_reader.c 2
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/shared_dictionary.c 2
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/dictionary.c 1
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/transform.c 4
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/huffman.c 3

Analyses and suggestions

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
LZ4_compress_fast_extState_fastReset /work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c 6 ['N/A', 'N/A', 'N/A', 'int', 'int', 'int'] 2 0 23893 2854 889 10 0 912 912
ots::OpenTypeCFF::Parse(unsignedcharconst*,unsignedlong) /work/build/../../src/ots/src/cff.cc 3 ['N/A', 'N/A', 'size_t'] 9 0 474 97 92 103 0 917 872
LZ4_compress_continue /work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c 4 ['N/A', 'N/A', 'N/A', 'int'] 3 0 26 3 2 12 0 890 867
LZ4_compress_destSize /work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c 4 ['N/A', 'N/A', 'N/A', 'int'] 4 0 31 3 2 15 0 885 862
ots::OpenTypeGPOS::ParseLookupSubtable(unsignedcharconst*,unsignedlong,unsignedshort) /work/build/../../src/ots/src/gpos.cc 4 ['N/A', 'N/A', 'size_t', 'short'] 7 0 104 14 15 114 0 740 691
LZ4_decompress_safe_continue /work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c 5 ['N/A', 'N/A', 'N/A', 'int', 'int'] 3 0 2422 311 113 8 0 546 540
ots::OpenTypeGLYF::Parse(unsignedcharconst*,unsignedlong) /work/build/../../src/ots/src/glyf.cc 3 ['N/A', 'N/A', 'size_t'] 3 0 732 128 129 57 0 528 470
LZ4_decompress_safe_partial_usingDict /work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c 7 ['N/A', 'N/A', 'int', 'int', 'int', 'N/A', 'int'] 3 0 91 10 5 8 0 442 433
ots::OpenTypeCOLR::Parse(unsignedcharconst*,unsignedlong) /work/build/../../src/ots/src/colr.cc 3 ['N/A', 'N/A', 'size_t'] 11 0 702 139 20 99 0 488 368
LZ4_compress_forceExtDict /work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c 4 ['N/A', 'N/A', 'N/A', 'int'] 2 0 7802 919 284 10 0 310 284

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

Functions statically reachable by fuzzers
42.0%
380 / 902
Cyclomatic complexity statically reachable by fuzzers
69.0%
9367 / 13547

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

Files and Directories in report

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
[] []
/work/build/../../src/ots/src/avar.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/prep.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/stat.cc [] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/platform.c [] []
/work/build/../../src/ots/src/gdef.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/silf.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/stat.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/name.cc [] []
/work/build/../../src/ots/src/fpgm.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/cff_charstring.h [] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/state.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/gvar.cc ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/woff2_common.cc ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/inftrees.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/avar.cc [] []
/work/build/../../src/ots/src/head.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/uncompr.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/head.cc [] []
/work/build/../../src/ots/src/fvar.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/feat.cc [] []
/work/build/../../src/ots/src/mvar.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/gpos.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/post.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/vmtx.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./woff2_common.h [] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/adler32.c ['ots-fuzzer'] []
/usr/local/bin/../include/c++/v1/stdexcept [] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/inffast.c ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./round.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/fvar.cc [] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/huffman.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/cmap.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/maxp.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/variations.cc [] []
/work/build/../../src/ots/src/fpgm.cc [] []
/work/build/../../src/ots/src/ots.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/loca.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/loca.cc [] []
/work/build/../../src/ots/src/sill.cc [] []
/work/build/../../src/ots/src/vvar.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/vdmx.cc [] []
/work/build/../../src/ots/src/cmap.cc [] []
/work/build/../../src/ots/src/vvar.cc [] []
/work/build/../../src/ots/src/layout.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/gsub.cc [] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/bit_reader.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/kern.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/sile.cc [] []
/work/build/../../src/ots/src/hhea.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/gdef.cc [] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/zutil.c [] []
/work/build/../../src/ots/src/hvar.cc [] []
/work/build/../../src/ots/src/gloc.cc [] []
/work/build/../../src/ots/src/vdmx.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/cpal.cc [] []
/work/build/../../src/ots/src/cvt.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/silf.cc [] []
/work/build/../../src/ots/src/cvar.cc [] []
/work/build/../../src/ots/src/metrics.cc [] []
/work/build/../../src/ots/src/ltsh.cc [] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./buffer.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/gpos.cc [] []
/work/build/../../src/ots/src/cvt.cc [] []
/work/build/../../src/ots/src/glyf.cc [] []
/work/build/../../src/ots/src/maxp.cc [] []
/work/build/../../src/ots/src/vhea.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/post.cc [] []
/work/build/../../src/ots/src/hdmx.cc [] []
/work/build/../../src/ots/src/cpal.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/glat.cc [] []
/work/build/../../src/ots/src/math.cc [] []
/work/build/../../src/ots/src/prep.cc [] []
/work/build/../../src/ots/src/mvar.cc [] []
/work/build/../../src/ots/src/vorg.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/colr.cc [] []
/work/build/../../src/ots/src/metrics.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/feat.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/cff_charstring.cc [] []
/work/build/../../src/ots/src/graphite.h [] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/inflate.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/gloc.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/transform.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/cvar.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/dictionary.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/gvar.h ['ots-fuzzer'] []
/work/build/../../src/ots/util/ots-fuzzer.cc ['ots-fuzzer'] []
/work/build/../../src/ots/src/os2.cc [] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/shared_dictionary.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/hhea.cc [] []
/work/build/../../src/ots/src/vhea.cc [] []
/work/build/../../src/ots/src/name.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/gasp.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/math_.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/lz4-1.9.4/lib/lz4.c [] []
/work/build/../../src/ots/src/hmtx.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/glyf.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/hdmx.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/cff.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./store_bytes.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/gsub.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/sill.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/colr.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/vorg.cc [] []
/work/build/../../src/ots/include/ots-memory-stream.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/cff.cc [] []
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/decode.c ['ots-fuzzer'] []
/work/build/../../src/ots/src/ots.cc ['ots-fuzzer'] []
/work/build/../../src/ots/include/opentype-sanitiser.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/sile.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/variable_length.cc ['ots-fuzzer'] []
/work/build/../../src/ots/src/layout.cc [] []
/work/build/../../src/ots/src/gasp.cc [] []
/usr/local/bin/../include/c++/v1/string [] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/include/woff2/output.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/glat.h ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/zlib-1.3.1/crc32.c ['ots-fuzzer'] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/woff2_out.cc ['ots-fuzzer'] []
/work/build/../../src/ots/src/ltsh.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/kern.cc [] []
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/woff2_dec.cc ['ots-fuzzer'] []
/work/build/../../src/ots/src/os2.h ['ots-fuzzer'] []
/work/build/../../src/ots/src/hvar.h ['ots-fuzzer'] []

Directories in report

Directory
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/
/work/build/../../src/ots/util/
/work/build/../../src/ots/subprojects/lz4-1.9.4/lib/
/work/build/../../src/ots/subprojects/zlib-1.3.1/
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/dec/
/work/build/../../src/ots/src/
/usr/local/bin/../include/c++/v1/
/work/build/../../src/ots/subprojects/brotli-1.1.0/c/common/
/work/build/../../src/ots/include/
/work/build/../../src/ots/subprojects/woff2-1.0.2/include/woff2/
/work/build/../../src/ots/subprojects/woff2-1.0.2/src/./