skia2/site/dev/testing/fuzz.md
Kevin Lubick 00587e32b8 Prevent UBSAN from complaining too early about invalid enums
This is making reproducing https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15052
difficult.

Docs-Preview: https://skia.org/?cl=217457
Change-Id: I131e8c1b64f621178696b94b63bd09513ca6c170
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/217457
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
2019-06-03 15:58:36 +00:00

1.1 KiB

Reproducing Skia Fuzzes

We assume that you can build Skia. Many fuzzes only reproduce when building with ASAN or MSAN; see those instructions for more details.

When building, you should add the following args to BUILD.gn to make reproducing less machine- and platform- dependent:

skia_use_fontconfig=false
skia_use_freetype=true
skia_use_system_freetype2=false
skia_use_wuffs=true
skia_enable_skottie=true

All that is needed to reproduce a fuzz downloaded from ClusterFuzz, oss-fuzz or fuzzer.skia.org is to run something like:

out/ASAN/fuzz -b /path/to/downloaded/testcase

The fuzz binary will try its best to guess what the type/name should be based on the name of the testcase. Manually providing type and name is also supported, like:

out/ASAN/fuzz -t filter_fuzz -b /path/to/downloaded/testcase
out/ASAN/fuzz -t api -n RasterN32Canvas -b /path/to/downloaded/testcase

To enumerate all supported types and names, run the following:

out/ASAN/fuzz --help  # will list all types
out/ASAN/fuzz -t api  # will list all names