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

Fuzzer details

Fuzzer: fuzz_open_workbook

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 0 952 77.8%
gold [1:9] 0 0.0%
yellow [10:29] 0 0.0%
greenyellow [30:49] 0 0.0%
lawngreen 50+ 271 22.1%
All colors 1223 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
202 317 xlrd.sheet.Sheet.fixed_BIFF2_xfindex call site: 00317 xlrd.formula.decompile_formula
175 1029 xlrd.book.Book.names_epilogue call site: 01029 xlrd.formula.evaluate_name_formula
99 689 xlrd.book.Book.handle_country call site: 00689 xlrd.formula.decompile_formula
46 909 xlrd.book.Book.parse_globals call site: 00909 xlrd.book.Book.handle_boundsheet
45 576 xlrd.sheet.Sheet.read call site: 00576 xlrd.sheet.Sheet.handle_hlink
32 645 xlrd.sheet.Sheet.read call site: 00645 xlrd.sheet.Sheet.handle_note
31 977 xlrd.book.Book.parse_globals call site: 00977 xlrd.book.Book.handle_sheethdr
21 274 xlrd.sheet.Sheet.read call site: 00274 xlrd.biffh.BaseObject.dump
19 956 xlrd.book.Book.parse_globals call site: 00956 xlrd.book.Book.handle_externsheet
18 867 xlrd.sheet.Sheet.read call site: 00867 xlrd.sheet.Sheet.fixed_BIFF2_xfindex
15 560 xlrd.sheet.Sheet.read call site: 00560 xlrd.sheet.Sheet.put_cell_ragged
15 623 xlrd.sheet.Sheet.read call site: 00623 xlrd.biffh.BaseObject.dump

Runtime coverage analysis

Covered functions
90
Functions that are reachable but not covered
154
Reachable functions
213
Percentage of reachable functions covered
27.7%
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
/ 1
...fuzz_open_workbook 3
xlrd 10
xlrd.book 74
xlrd.compdoc 28
xlrd.timemachine 6
xlrd.formatting 6
xlrd.sheet 80
xlrd.biffh 17
xlrd.formula 56

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
xlrd.book.Name.area2d 38 19 50.0% []
xlrd.book.Book.derive_encoding 33 14 42.42% ['fuzz_open_workbook']
xlrd.book.Book.handle_externsheet 35 0 0.0% ['fuzz_open_workbook']
xlrd.book.Book.handle_name 34 4 11.76% ['fuzz_open_workbook']
xlrd.book.Book.names_epilogue 56 13 23.21% ['fuzz_open_workbook']
xlrd.book.Book.handle_supbook 38 0 0.0% ['fuzz_open_workbook']
xlrd.book.unpack_SST_table 69 0 0.0% ['fuzz_open_workbook']
xlrd.biffh.biff_dump 42 0 0.0% []
xlrd.compdoc.CompDoc._locate_stream 32 0 0.0% ['fuzz_open_workbook']
xlrd.sheet.Sheet.tidy_dimensions 37 20 54.05% ['fuzz_open_workbook']
xlrd.sheet.Sheet.put_cell_ragged 46 0 0.0% ['fuzz_open_workbook']
xlrd.sheet.Sheet.read 483 223 46.16% ['fuzz_open_workbook']
xlrd.sheet.Sheet.handle_hlink.get_nul_terminated_unicode 70 0 0.0% ['fuzz_open_workbook']
xlrd.sheet.Sheet.handle_obj 40 2 5.0% ['fuzz_open_workbook']
xlrd.sheet.Sheet.handle_note 43 0 0.0% ['fuzz_open_workbook']
xlrd.sheet.Sheet.handle_txo 40 2 5.0% ['fuzz_open_workbook']
xlrd.formatting.handle_font 62 7 11.29% []
xlrd.formatting.is_date_format_string 44 17 38.63% []
xlrd.formatting.handle_style 33 2 6.060% []
xlrd.formatting.handle_xf 129 21 16.27% []
xlrd.formatting.xf_epilogue.check_same 41 8 19.51% []
xlrd.formula.get_externsheet_local_range 34 0 0.0% ['fuzz_open_workbook']
xlrd.formula.evaluate_name_formula.not_in_name_formula 416 0 0.0% ['fuzz_open_workbook']
xlrd.formula.decompile_formula.unexpected_opcode 368 0 0.0% ['fuzz_open_workbook']
xlrd.formula.dump_formula 142 0 0.0% ['fuzz_open_workbook']