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: gd_image_string_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 6 15.7%
gold [1:9] 0 0.0%
yellow [10:29] 4 10.5%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 28 73.6%
All colors 38 100

Fuzz blockers

The following nodes represent call sites where fuzz blockers occur.

Amount of callsites blocked Calltree index Parent function Callsite Largest blocked function
3 19 gdCalloc call site: 00019
2 8 _gd_error_ex call site: 00008 gd_error_ex
1 16 gdImageCreateTrueColor call site: 00016

Runtime coverage analysis

Covered functions
21
Functions that are reachable but not covered
12
Reachable functions
27
Percentage of reachable functions covered
55.56%
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
gd_image_string_fuzzer.cc 15
libgdgd.c 9
libgdgd_security.c 1
libgdgdhelpers.c 2

Fuzzer: parser_target.cc

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 0 0.0%
gold [1:9] 2 66.6%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 1 33.3%
All colors 3 100

Runtime coverage analysis

Covered functions
115
Functions that are reachable but not covered
1
Reachable functions
3
Percentage of reachable functions covered
66.67%
NB: The sum of covered functions and functions that are reachable but not covered need not be equal to Reachable functions . This is because the reachability analysis is an approximation and thus at runtime some functions may be covered that are not included in the reachability analysis. This is a limitation of our static analysis capabilities.
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
parser_target.cc 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
assert_roundtrip /src/libgd/tests/bmp/bmp_write_ex.c 6 ['gdImagePtr', 'int', 'int', 'int', 'int', 'int'] 9 0 9 2 1 152 0 720 708
BGD_DECLARE /src/libgd/src/gdft.c 10 ['gdImagePtr', 'int*', 'int', 'char*', 'double', 'double', 'int', 'int', 'char*', 'gdFTStringExtraPtr'] 5 0 334 72 92 71 0 339 335
gdUhdrImageWritePtr /src/libgd/src/gd_uhdr.c 5 ['gdUhdrImagePtr', 'int*', 'int', 'int', 'gdUhdrErrorPtr'] 12 0 25 5 4 131 0 387 328
read_all_frames /src/libgd/tests/gif/gif_conformance.c 1 ['gif_case_t*'] 8 0 32 3 5 79 1 269 239
gdImageCreateFromTiffCtxEx /src/libgd/src/gd_tiff.c 2 ['gdIOCtx*', 'int'] 4 0 153 37 55 47 0 160 137
testDrawing /src/libgd/src/testac.c 5 ['gdImagePtr', 'double', 'int', 'int', 'char*'] 7 0 13 2 1 89 0 342 130
assert_getimage_dims /src/libgd/tests/gdimageaffine/matrix.c 6 ['char*', 'gdImagePtr', 'gdRectPtr', 'double[]', 'int', 'int'] 8 0 7 2 2 57 1 141 104
_gd2CreateFromFile /src/libgd/src/gd_gd2.c 9 ['gdIOCtxPtr', 'int*', 'int*', 'int*', 'int*', 'int*', 'int*', 'int*', 't_chunk_info**'] 5 0 33 5 7 26 0 116 94
gdImageCreateFromTga /src/libgd/src/gd_tga.c 1 ['FILE*'] 6 0 6 2 1 49 1 120 91
gdImageGifAnimAddPtr /src/libgd/src/gd_gif_out.c 8 ['gdImagePtr', 'int*', 'int', 'int', 'int', 'int', 'int', 'gdImagePtr'] 8 0 10 3 2 88 0 314 85

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

Functions statically reachable by fuzzers
27.0%
324 / 1207
Cyclomatic complexity statically reachable by fuzzers
48.0%
2264 / 4728

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

Fuzz driver synthesis

New fuzzers

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

bmp_write_ex.c

Target file: /src/libgd/tests/bmp/bmp_write_ex.c
Target functions: assert_roundtrip
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target assert_roundtrip */
  UNKNOWN_TYPE unknown_0;
  int new_var1 = ada_safe_get_int();
  int new_var2 = ada_safe_get_int();
  int new_var3 = ada_safe_get_int();
  int new_var4 = ada_safe_get_int();
  int new_var5 = ada_safe_get_int();
  assert_roundtrip(unknown_0, new_var1, new_var2, new_var3, new_var4, new_var5);

  af_safe_gb_cleanup();
}

gdft.c

Target file: /src/libgd/src/gdft.c
Target functions: BGD_DECLARE
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target BGD_DECLARE */
  UNKNOWN_TYPE unknown_6;
  int *new_var7 = af_get_int_p();
  int new_var8 = ada_safe_get_int();
  char *new_var9 = ada_safe_get_char_p();
  UNKNOWN_TYPE unknown_10;
  UNKNOWN_TYPE unknown_11;
  int new_var12 = ada_safe_get_int();
  int new_var13 = ada_safe_get_int();
  char *new_var14 = ada_safe_get_char_p();
  UNKNOWN_TYPE unknown_15;
  BGD_DECLARE(unknown_6, new_var7, new_var8, new_var9, unknown_10, unknown_11, new_var12, new_var13, new_var14, unknown_15);

  af_safe_gb_cleanup();
}

gd_uhdr.c

Target file: /src/libgd/src/gd_uhdr.c
Target functions: gdUhdrImageWritePtr
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target gdUhdrImageWritePtr */
  UNKNOWN_TYPE unknown_16;
  int *new_var17 = af_get_int_p();
  int new_var18 = ada_safe_get_int();
  int new_var19 = ada_safe_get_int();
  UNKNOWN_TYPE unknown_20;
  gdUhdrImageWritePtr(unknown_16, new_var17, new_var18, new_var19, unknown_20);

  af_safe_gb_cleanup();
}

gif_conformance.c

Target file: /src/libgd/tests/gif/gif_conformance.c
Target functions: read_all_frames
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target read_all_frames */
  UNKNOWN_TYPE unknown_21;
  read_all_frames(unknown_21);

  af_safe_gb_cleanup();
}

gd_tiff.c

Target file: /src/libgd/src/gd_tiff.c
Target functions: gdImageCreateFromTiffCtxEx
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target gdImageCreateFromTiffCtxEx */
  UNKNOWN_TYPE unknown_22;
  int new_var23 = ada_safe_get_int();
  gdImageCreateFromTiffCtxEx(unknown_22, new_var23);

  af_safe_gb_cleanup();
}

testac.c

Target file: /src/libgd/src/testac.c
Target functions: testDrawing
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target testDrawing */
  UNKNOWN_TYPE unknown_24;
  UNKNOWN_TYPE unknown_25;
  int new_var26 = ada_safe_get_int();
  int new_var27 = ada_safe_get_int();
  char *new_var28 = ada_safe_get_char_p();
  testDrawing(unknown_24, unknown_25, new_var26, new_var27, new_var28);

  af_safe_gb_cleanup();
}

matrix.c

Target file: /src/libgd/tests/gdimageaffine/matrix.c
Target functions: assert_getimage_dims
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target assert_getimage_dims */
  char *new_var29 = ada_safe_get_char_p();
  UNKNOWN_TYPE unknown_30;
  UNKNOWN_TYPE unknown_31;
  UNKNOWN_TYPE unknown_32;
  int new_var33 = ada_safe_get_int();
  int new_var34 = ada_safe_get_int();
  assert_getimage_dims(new_var29, unknown_30, unknown_31, unknown_32, new_var33, new_var34);

  af_safe_gb_cleanup();
}

gd_gd2.c

Target file: /src/libgd/src/gd_gd2.c
Target functions: _gd2CreateFromFile
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target _gd2CreateFromFile */
  UNKNOWN_TYPE unknown_35;
  int *new_var36 = af_get_int_p();
  int *new_var37 = af_get_int_p();
  int *new_var38 = af_get_int_p();
  int *new_var39 = af_get_int_p();
  int *new_var40 = af_get_int_p();
  int *new_var41 = af_get_int_p();
  int *new_var42 = af_get_int_p();
  UNKNOWN_TYPE unknown_43;
  _gd2CreateFromFile(unknown_35, new_var36, new_var37, new_var38, new_var39, new_var40, new_var41, new_var42, unknown_43);

  af_safe_gb_cleanup();
}

gd_tga.c

Target file: /src/libgd/src/gd_tga.c
Target functions: gdImageCreateFromTga
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target gdImageCreateFromTga */
  UNKNOWN_TYPE unknown_44;
  gdImageCreateFromTga(unknown_44);

  af_safe_gb_cleanup();
}

gd_gif_out.c

Target file: /src/libgd/src/gd_gif_out.c
Target functions: gdImageGifAnimAddPtr
#include "ada_fuzz_header.h"

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  af_safe_gb_init(data, size);

  /* target gdImageGifAnimAddPtr */
  UNKNOWN_TYPE unknown_45;
  int *new_var46 = af_get_int_p();
  int new_var47 = ada_safe_get_int();
  int new_var48 = ada_safe_get_int();
  int new_var49 = ada_safe_get_int();
  int new_var50 = ada_safe_get_int();
  int new_var51 = ada_safe_get_int();
  UNKNOWN_TYPE unknown_52;
  gdImageGifAnimAddPtr(unknown_45, new_var46, new_var47, new_var48, new_var49, new_var50, new_var51, unknown_52);

  af_safe_gb_cleanup();
}

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
/src/libgd/tests/gif/gif_conformance.c [] []
/src/libgd/src/gd_io_dp.c [] []
/src/libgd/tests/png/bug00193.c [] []
/src/libgd/tests/perceptualdiff/test_core.c [] []
/src/libgd/src/gd_png.c [] []
/src/libgd/src/gd_io_stream.cxx [] []
/src/libgd/src/gdft.c [] []
/src/libgd/src/gdtestft.c [] []
/src/libgd/tests/gdimagefilter/gdCopyBlurred.c [] []
/src/gd_image_string_fuzzer.cc ['gd_image_string_fuzzer'] ['gd_image_string_fuzzer']
/src/libgd/src/gdkanji.c [] []
/src/libgd/examples/gif_rewrite.c [] []
/src/libgd/src/gd_tiff.c [] []
/src/libgd/tests/gdimagecopyrotated/bug00320.c [] []
/src/libgd/tests/bmp/bug00275.c [] []
/src/libgd/tests/gdimageaffine/matrix.c [] []
/src/libgd/src/msinttypes/stdint.h [] []
/src/libgd/tests/bmp/bmp_im2im.c [] []
/src/libgd/src/gd_heif.c [] []
/src/libgd/tests/gif/bug000971.c [] []
/src/libgd/src/gd_rotate.c [] []
/src/libgd/tests/tiff/tiff_dpi.c [] []
/src/libgd/src/gdfx.c [] []
/src/libgd/tests/gdimagecontrast/basic.c [] []
/src/libgd/src/gd_avif.c [] []
/src/libgd/src/gdcache.c [] []
/src/libgd/tests/jpeg/bug00338.c [] []
/src/libgd/tests/wbmp/wbmp_im2im.c [] []
/src/libgd/tests/metadata/metadata_core.c [] []
/src/libgd/src/fontsizetest.c [] []
/src/libgd/src/gd_interpolation.c [] []
/src/libgd/tests/gdimagescale/bug00329.c [] []
/src/libgd/tests/gdimagecopyrotated/bug00981_2.c [] []
/src/libgd/src/gd_crop.c [] []
/src/libgd/src/gd_color_map.c [] []
/src/libgd/examples/flip.c [] []
/src/libgd/src/gd_jpeg.c [] []
/src/libgd/src/gd_matrix.c [] []
/src/libgd/tests/bmp/bmp_size.c [] []
/src/libgd/examples/jpeg2avifex.c [] []
/src/libgd/src/gd_intern.h [] []
/src/libgd/examples/uhdr.c [] []
/src/libgd/tests/png/png_conformance.c [] []
/src/libgd/tests/metadata/png_metadata.c [] []
/src/libgd/src/gd_topal.c [] []
/src/libgd/tests/uhdr/uhdr_cli_parity_noop.c [] []
/src/libgd/src/gd_tga.c [] []
/src/libgd/src/gdfonts.c [] []
/src/libgd/src/fontwheeltest.c [] []
/src/libgd/src/gd_filename.c [] []
/src/libgd/tests/gdimagetruecolortopalette/neuquant_palette_order.c [] []
/src/libgd/tests/metadata/jpeg_exiv2.cpp [] []
/src/libgd/src/gd_wbmp.c [] []
/src/libgd/tests/tga/tga_read.c [] []
/src/libgd/tests/webp/webp_conformance.c [] []
/src/libgd/tests/gdimagecopyresampled/bug00201.c [] []
/src/libgd/src/gd_gd2.c [] []
/src/libgd/examples/png2avif.c [] []
/src/libgd/tests/uhdr/uhdr_metadata_resize.c [] []
/src/libgd/tests/png/png_im2im.c [] []
/src/libgd/src/gd_metadata.c [] []
/src/libgd/src/gd_uhdr.c [] []
/src/libgd/src/gd_io_ss.c [] []
/src/libgd/tests/bmp/bmp_write_ex.c [] []
/src/libgd/src/gdxpm.c [] []
/src/libgd/src/getopt.c [] []
/src/libgd/tests/gdimagepixelate/gdimagepixelate.c [] []
/src/libgd/src/gdfontl.c [] []
/src/libgd/src/gd_io.c [] []
/src/libgd/src/gdtest.c [] []
/src/libgd/tests/webp/webp_anim.c [] []
/src/libgd/src/gdfontmb.c [] []
/src/libgd/src/gd_gd.c [] []
/src/libgd/src/gd.h [] []
/src/libgd/src/gd_nnquant.c [] []
/src/libgd/tests/uhdr/uhdr_cli_parity_quality_noop.c [] []
/src/libgd/src/gdpp.h [] []
/src/libgd/tests/uhdr/uhdr_roundtrip.c [] []
/src/libgd/tests/gdimagebrightness/basic.c [] []
/src/libgd/tests/gdimagecrop/bug00485_auto.c [] []
/src/libgd/src/gdfontg.c [] []
/src/libgd/tests/gd2/gd2_im2im.c [] []
/src/libgd/tests/bmp/bmpsuite_read.c [] []
/src/libgd/src/gd_xbm.c [] []
/src/libgd/tests/gdimageline/gdimageline_aa.c [] []
/src/libgd/tests/gdimageline/github_bug_167.c [] []
/src/libgd/src/gd_io_file.c [] []
/src/libgd/src/webpng.c [] []
/src/libgd/src/gd_bmp.c [] []
/src/libgd/examples/crop.c [] []
/src/libgd/src/gd_color.c [] []
/src/libgd/src/gdfontt.c [] []
/src/libgd/src/gd_io_stream.h [] []
/src/libgd/src/gd_transform.c [] []
/src/libgd/cmake/modules/TestForHighBitCharacters.c [] []
/src/libgd/tests/jpeg/jpeg_im2im.c [] []
/src/libgd/tests/gdtest/readdir.c [] []
/src/libgd/tests/gif/animated_gif_reader.c [] []
/src/libgd/src/gdhelpers.h [] []
/src/libgd/tests/gdimageconvolution/basic.c [] []
/src/libgd/src/gdhelpers.c ['gd_image_string_fuzzer'] ['gd_image_string_fuzzer']
/src/libgd/src/gd_version.c [] []
/src/libgd/src/wbmp.c [] []
/src/libgd/tests/gdimagetruecolortopalette/transparent_preserved.c [] []
/src/libgd/tests/gdimagerectangle/point_ordering.c [] []
/src/parser_target.cc ['parser_target.cc'] ['parser_target.cc']
/src/libgd/tests/tiff/tiff_invalid_read.c [] []
/src/libgd/src/gd_gif_in.c [] []
/src/libgd/tests/gdtest/gdtest.h [] []
/src/libgd/src/gd_gif_out.c [] []
/src/libgd/tests/gd/gd_im2im.c [] []
/src/libgd/examples/nnquant.c [] []
/src/libgd/src/gd_security.c ['gd_image_string_fuzzer'] ['gd_image_string_fuzzer']
/src/libgd/src/gd_qoi.h [] []
/src/libgd/examples/windows.c [] []
/src/libgd/tests/uhdr/uhdr_ptr_roundtrip.c [] []
/src/libgd/src/gdpp.cxx [] []
/src/libgd/tests/gdimagefile/gdnametest.c [] []
/src/libgd/tests/qoi/qoi_im2im.c [] []
/src/libgd/tests/metadata/jpeg_metadata.c [] []
/src/libgd/tests/gif/gif_im2im.c [] []
/src/libgd/tests/gdimageaffine/visual.c [] []
/src/libgd/tests/gdimageflip/gdimageflip.c [] []
/src/libgd/src/msinttypes/inttypes.h [] []
/src/libgd/tests/gdtest/gdtest.c [] []
/src/libgd/src/testac.c [] []
/src/libgd/tests/gdimagecolorreplace/gdimagecolorreplace.c [] []
/src/libgd/tests/gdinterpolatedscale/gdBicubicFixed.c [] []
/src/libgd/tests/gdinterpolatedscale/gdTrivialResize.c [] []
/src/libgd/tests/gdtest/gdpdiff.c [] []
/src/libgd/src/gd_filter.c [] []
/src/libgd/src/gd_qoi.c [] []
/src/libgd/examples/webp_frames.c [] []
/src/libgd/src/gd.c ['gd_image_string_fuzzer'] ['gd_image_string_fuzzer']
/src/libgd/src/gd_color_match.c [] []
/src/libgd/src/gd_ss.c [] []
/src/libgd/src/gd_webp.c [] []
/src/libgd/tests/qoi/qoi_conformance.c [] []

Directories in report

Directory
/src/libgd/tests/gdimageline/
/src/libgd/tests/gdimagefilter/
/src/libgd/tests/bmp/
/src/libgd/src/
/src/libgd/cmake/modules/
/src/libgd/tests/png/
/src/libgd/tests/gdtest/
/src/libgd/tests/metadata/
/src/libgd/tests/gdimagerectangle/
/src/libgd/tests/gdimageflip/
/src/libgd/tests/webp/
/src/libgd/tests/gdimagecrop/
/src/libgd/tests/gdimagecontrast/
/src/libgd/tests/tiff/
/src/libgd/tests/gdimageaffine/
/src/libgd/tests/gdimagescale/
/src/libgd/tests/wbmp/
/src/libgd/tests/gdimagebrightness/
/src/libgd/tests/jpeg/
/src/libgd/tests/gdimagecopyresampled/
/src/libgd/tests/uhdr/
/src/libgd/tests/gdimagecopyrotated/
/src/libgd/tests/gdimageconvolution/
/src/libgd/tests/perceptualdiff/
/src/libgd/tests/gdimagepixelate/
/src/libgd/tests/gdimagefile/
/src/libgd/src/msinttypes/
/src/
/src/libgd/tests/qoi/
/src/libgd/tests/gdinterpolatedscale/
/src/libgd/tests/gd/
/src/libgd/tests/tga/
/src/libgd/tests/gdimagetruecolortopalette/
/src/libgd/examples/
/src/libgd/tests/gd2/
/src/libgd/tests/gdimagecolorreplace/
/src/libgd/tests/gif/