Fuzz introspector
For issues and ideas: https://github.com/ossf/fuzz-introspector/issues
Project coverage
Per-fuzzer coverage

Table of contents

Project overview: libtiff
High level conclusions
Reachability and coverage overview
Fuzzers overview
Project functions overview
Fuzzer details
Fuzzer: tiff_read_rgba_fuzzer
Call tree
Fuzz blockers
Runtime coverage analysis
Files reached
Analyses and suggestions
Optimal target analysis
Remaining optimal interesting functions
All functions overview
Runtime coverage analysis
Complex functions with low coverage
Files and Directories in report
Files in report
Directories in report
Metadata section
Report generation date: 2022-11-14

Project overview: libtiff

High level conclusions

Reachability and coverage overview

Functions statically reachable by fuzzers
20.33%
309/1520
Cyclomatic complexity statically reachable by fuzzers
21.8%
2788/12787
Functions covered at runtime
597

Fuzzers overview

Fuzzer Fuzzer filename Functions Reached Functions unreached Fuzzer depth Files reached Basic blocks reached Cyclomatic complexity Details
tiff_read_rgba_fuzzer /src/libtiff/contrib/oss-fuzz/tiff_read_rgba_fuzzer.cc 309 1212 13 21 8182 2788 tiff_read_rgba_fuzzer.cc

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 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: tiff_read_rgba_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

Full calltree

Call tree overview bitmap:

The distribution of callsites in terms of coloring is
Color Runtime hitcount Callsite count Percentage
red 0 829 48.9%
gold [1:9] 58 3.42%
yellow [10:29] 63 3.71%
greenyellow [30:49] 25 1.47%
lawngreen 50+ 719 42.4%
All colors 1694 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
1605 1605 1 :

['TIFFFlush']

1605 1652 TIFFCleanup call site /src/libtiff/libtiff/tif_close.c:50
266 266 2 :

['TIFFjpeg_create_compress', 'getenv']

266 266 JPEGInitializeLibJPEG call site /src/libtiff/libtiff/tif_jpeg.c:2401
252 474 6 :

['inflate_fast', 'adler32', 'crc32', 'fixedtables', 'inflate_table', 'updatewindow']

252 474 inflate call site /src/zlib/inflate.c:855
71 288 2 :

['_TIFFFetchStrileValue', '_TIFFFillStriles']

71 288 _TIFFGetStrileOffsetOrByteCountValue call site /src/libtiff/libtiff/tif_dirread.c:7079
61 61 1 :

['TIFFSetupStrips']

61 4181 TIFFReadDirectory call site /src/libtiff/libtiff/tif_dirread.c:4431
60 60 1 :

['jinit_merged_upsampler']

60 791 master_selection call site /src/libjpeg-turbo/jdmaster.c:521
28 28 1 :

['do_barray_io']

28 30 access_virt_barray call site /src/libjpeg-turbo/jmemmgr.c:915
26 26 1 :

['LogLuvGuessDataFmt']

26 121 LogLuvInitState call site /src/libtiff/libtiff/tif_luv.c:1381
21 21 1 :

['deflateEnd']

21 71 ZIPSetupDecode call site /src/libtiff/libtiff/tif_zip.c:107
21 21 1 :

['deflateEnd']

21 68 PixarLogCleanup call site /src/libtiff/libtiff/tif_pixarlog.c:1298
21 21 1 :

['deflateEnd']

21 66 ZIPCleanup call site /src/libtiff/libtiff/tif_zip.c:507
11 11 1 :

['LogL16GuessDataFmt']

11 106 LogL16InitState call site /src/libtiff/libtiff/tif_luv.c:1282

Runtime coverage analysis

Covered functions
597
Functions that are reachable but not covered
133
Reachable functions
309
Percentage of reachable functions covered
56.96%
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
/src/libtiff/contrib/oss-fuzz/tiff_read_rgba_fuzzer.cc 2
/src/libtiff/libtiff/tif_error.c 3
/src/libtiff/libtiff/tif_warning.c 2
/src/libtiff/libtiff/tif_stream.cxx 6
/src/libtiff/libtiff/tif_open.c 5
/src/libtiff/libtiff/tif_unix.c 7
/src/libtiff/libtiff/tif_compress.c 16
/src/libtiff/libtiff/tif_swab.c 10
/src/libtiff/libtiff/tif_dir.c 19
/src/libtiff/libtiff/tif_dirinfo.c 12
/src/libtiff/libtiff/tif_aux.c 12
/src/libtiff/libtiff/tif_read.c 5
/src/libtiff/libtiff/tif_dirread.c 105
/src/libtiff/libtiff/tif_codec.c 1
/src/libtiff/libtiff/tif_strip.c 6
/src/libtiff/libtiff/tif_tile.c 5
/src/libtiff/libtiff/tif_write.c 3
/src/libtiff/libtiff/tif_close.c 2
/src/libtiff/libtiff/tif_flush.c 3
/src/libtiff/libtiff/tif_dirwrite.c 67
/src/libtiff/libtiff/tif_getimage.c 5

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
TIFFInitJPEG /src/libtiff/libtiff/tif_jpeg.c 2 ['struct.tiff.89 *', 'int '] 7 0 158 17 6 479 0 3985 3471
TIFFInitPixarLog /src/libtiff/libtiff/tif_pixarlog.c 2 ['struct.tiff *', 'int '] 7 0 156 12 4 172 0 1504 1213
TIFFInitCCITTFax4 /src/libtiff/libtiff/tif_fax3.c 2 ['struct.tiff *', 'int '] 4 0 70 8 4 82 0 954 690
encode_mcu_huff /src/libjpeg-turbo/jchuff.c 2 ['struct.jpeg_compress_struct *', 'N/A'] 2 0 243 33 14 7 0 531 507
TIFFInitOJPEG /src/libtiff/libtiff/tif_ojpeg.c 2 ['struct.tiff *', 'int '] 7 0 165 11 4 320 0 2773 468
TIFFInitSGILog /src/libtiff/libtiff/tif_luv.c 2 ['struct.tiff *', 'int '] 4 0 152 15 5 108 0 655 374
TIFFReadRGBATile /src/libtiff/libtiff/tif_getimage.c 4 ['struct.tiff *', 'int ', 'int ', 'int *'] 5 0 28 3 2 84 0 495 335
gtTileSeparate /src/libtiff/libtiff/tif_getimage.c 4 ['struct._TIFFRGBAImage *', 'int *', 'int ', 'int '] 10 0 771 98 33 76 0 602 194
TIFFInitLZW /src/libtiff/libtiff/tif_lzw.c 2 ['struct.tiff *', 'int '] 7 0 124 10 3 91 0 553 155
gtStripSeparate /src/libtiff/libtiff/tif_getimage.c 4 ['struct._TIFFRGBAImage *', 'int *', 'int ', 'int '] 9 0 729 96 32 75 0 580 116

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

Functions statically reachable by fuzzers
70.0%
1064/1520
Cyclomatic complexity statically reachable by fuzzers
80.64%
10311 / 12787

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

Runtime coverage analysis

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
jpeg_consume_input 31 17 54.83% []
start_pass 188 40 21.27% []
jinit_color_deconverter 125 45 36.0% []
jpeg_core_output_dimensions 123 25 20.32% []
use_merged_upsample 36 4 11.11% []
start_pass_dpost 33 12 36.36% []
realize_virt_arrays 84 41 48.80% []
jsimd_ycc_rgb_convert 42 12 28.57% []
TIFFVGetFieldDefaulted 136 44 32.35% ['tiff_read_rgba_fuzzer']
_TIFFVGetField 315 94 29.84% ['tiff_read_rgba_fuzzer']
_TIFFCheckDirNumberAndOffset 51 25 49.01% ['tiff_read_rgba_fuzzer']
TIFFFetchDirectory 234 127 54.27% ['tiff_read_rgba_fuzzer']
TIFFReadDirEntrySbyteArray 177 28 15.81% ['tiff_read_rgba_fuzzer']
TIFFReadDirEntrySshortArray 165 28 16.96% ['tiff_read_rgba_fuzzer']
TIFFReadDirEntrySlongArray 159 26 16.35% ['tiff_read_rgba_fuzzer']
TIFFReadDirEntrySlong8Array 148 24 16.21% ['tiff_read_rgba_fuzzer']
_TIFFGetStrileOffsetOrByteCountValue 33 13 39.39% ['tiff_read_rgba_fuzzer']
_TIFFFillStrilesInternal 33 5 15.15% ['tiff_read_rgba_fuzzer']
TIFFInitJPEG 39 18 46.15% []
LogLuvInitState 44 19 43.18% []
LogLuvVSetField 50 22 44.0% []
OJPEGVGetField 39 15 38.46% []
PixarLogVSetField 50 10 20.0% []
PredictorSetupDecode 51 24 47.05% []
TIFFReadEncodedTile 36 19 52.77% []
_tiffisSeekProc(void*,unsignedlong,int) 31 14 45.16% []
TIFFCheckTile 33 15 45.45% []
ZIPVSetField 47 8 17.02% []

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/libtiff/libtiff/tif_ojpeg.c [] []
/src/libjpeg-turbo/jdcolor.c [] []
/src/libtiff/libtiff/tif_dirwrite.c ['tiff_read_rgba_fuzzer'] []
/src/libjpeg-turbo/jfdctflt.c [] []
/src/libtiff/libtiff/tif_zip.c [] []
/src/zlib/deflate.c [] []
/src/libtiff/libtiff/tif_lzw.c [] []
/src/libjpeg-turbo/jdmerge.c [] []
/src/libjpeg-turbo/jdarith.c [] []
/src/libjpeg-turbo/jdsample.c [] []
/src/libjpeg-turbo/jidctfst.c [] []
/src/libtiff/contrib/oss-fuzz/tiff_read_rgba_fuzzer.cc ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jerror.c [] []
/src/libtiff/libtiff/tif_getimage.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jcprepct.c [] []
/src/libtiff/libtiff/tif_aux.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/usr/local/bin/../include/c++/v1/stdexcept [] []
/src/libjpeg-turbo/jdmainct.c [] []
/src/libtiff/libtiff/tif_open.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libtiff/libtiff/tif_dirread.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jidctred.c [] []
/src/libtiff/libtiff/tif_color.c [] []
/src/libjpeg-turbo/simd/x86_64/jsimd.c [] []
/src/libjpeg-turbo/jdphuff.c [] []
/src/libtiff/libtiff/tif_thunder.c [] []
/src/libjpeg-turbo/jcapistd.c [] []
/src/libjpeg-turbo/jdmaster.c [] []
/src/libtiff/libtiff/tif_swab.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jcarith.c [] []
/src/libtiff/libtiff/tif_fax3.c [] []
/src/libjpeg-turbo/jfdctfst.c [] []
/src/zlib/zutil.c [] []
/src/libtiff/libtiff/tif_flush.c ['tiff_read_rgba_fuzzer'] []
/src/libjpeg-turbo/jcparam.c [] []
/src/libtiff/libtiff/tif_unix.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jmemnobs.c [] []
/src/zlib/inffast.c [] []
/src/libtiff/libtiff/tif_tile.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jdinput.c [] []
/src/libjpeg-turbo/jquant1.c [] []
/src/libtiff/libtiff/tif_codec.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libtiff/libtiff/tif_dir.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/zlib/adler32.c [] []
/src/libjpeg-turbo/jmemmgr.c [] []
/src/libtiff/libtiff/tif_predict.c [] []
/src/libjpeg-turbo/jdhuff.c [] []
/src/libtiff/libtiff/tif_pixarlog.c [] []
/src/libjpeg-turbo/jdmarker.c [] []
/src/libtiff/libtiff/tif_strip.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libtiff/libtiff/tif_error.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jcmaster.c [] []
/src/zlib/inftrees.c [] []
/src/libjpeg-turbo/jcomapi.c [] []
/src/libtiff/libtiff/tif_luv.c [] []
/src/libjpeg-turbo/jcsample.c [] []
/src/libjpeg-turbo/jcphuff.c [] []
/src/libjpeg-turbo/jddctmgr.c [] []
/src/libjpeg-turbo/jdcoefct.c [] []
/src/libjpeg-turbo/jcmainct.c [] []
/src/libjpeg-turbo/jdcoefct.h [] []
/src/libjpeg-turbo/jidctflt.c [] []
/src/libjpeg-turbo/jcdctmgr.c [] []
/src/libjpeg-turbo/jccoefct.c [] []
/src/libtiff/libtiff/tif_dumpmode.c [] []
/src/libjpeg-turbo/jcinit.c [] []
/src/libjpeg-turbo/jstdhuff.c [] []
/src/libjpeg-turbo/jdpostct.c [] []
/src/zlib/trees.c [] []
/src/libjpeg-turbo/jdapimin.c [] []
/src/libtiff/libtiff/tif_packbits.c [] []
/src/libtiff/libtiff/tif_next.c [] []
/src/libtiff/libtiff/tif_stream.cxx ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libtiff/libtiff/tif_close.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libjpeg-turbo/jccolor.c [] []
/src/libtiff/libtiff/tif_warning.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libtiff/libtiff/tif_compress.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/libtiff/libtiff/tif_write.c ['tiff_read_rgba_fuzzer'] []
/src/libtiff/libtiff/tif_dirinfo.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']
/src/zlib/inflate.c [] []
/src/libtiff/libtiff/tif_lzma.c [] []
/src/libjpeg-turbo/jcapimin.c [] []
/src/libjpeg-turbo/jdmainct.h [] []
/src/libjpeg-turbo/jutils.c [] []
/src/libjpeg-turbo/jcmarker.c [] []
/src/libjpeg-turbo/jquant2.c [] []
/src/libtiff/libtiff/tif_jbig.c [] []
/src/libtiff/libtiff/tif_jpeg.c [] []
/src/libjpeg-turbo/jdapistd.c [] []
/src/zlib/crc32.c [] []
/src/libjpeg-turbo/jfdctint.c [] []
/src/libjpeg-turbo/jchuff.c [] []
/src/libjpeg-turbo/jidctint.c [] []
/src/libtiff/libtiff/tif_read.c ['tiff_read_rgba_fuzzer'] ['tiff_read_rgba_fuzzer']

Directories in report

Directory
/src/libtiff/libtiff/
/src/libtiff/contrib/oss-fuzz/
/src/zlib/
/src/libjpeg-turbo/
/usr/local/bin/../include/c++/v1/
/src/libjpeg-turbo/simd/x86_64/

Metadata section

This sections shows the raw data that is used to produce this report. This is mainly used for further processing and developer debugging.

Fuzzer Calltree file Program data file Coverage file
tiff_read_rgba_fuzzer fuzzerLogFile-0-45KaEmpMnQ.data fuzzerLogFile-0-45KaEmpMnQ.data.yaml tiff_read_rgba_fuzzer.covreport