Summary:
This was an experimental feature. After evaluating it with:
1) https://github.com/google/fuzzer-test-suite/tree/master/engine-comparison
2) enabling on real world fuzz targets running at ClusterFuzz and OSS-Fuzz
The following conclusions were made:
1) With fuzz targets that have reached a code coverage plateau, the feature does
not improve libFuzzer's ability to discover new coverage and may actually
negatively impact it.
2) With fuzz targets that have not yet reached a code coverage plateau, the
feature might speed up new units discovery in some cases, but it is quite
rare and hard to confirm with a high level on confidence.
Revert of https://reviews.llvm.org/D48054 and https://reviews.llvm.org/D49621.
Reviewers: metzman, morehouse
Reviewed By: metzman, morehouse
Subscribers: delcypher, #sanitizers, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D51455
llvm-svn: 340976
Summary:
Added functions that calculate stats while fuzz targets are running and give
mutations weight based on how much new coverage they provide, and choose better
performing mutations more often.
Patch by Kodé Williams (@kodewilliams).
Reviewers: Dor1s, metzman, morehouse
Reviewed By: Dor1s, morehouse
Subscribers: delcypher, kcc, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D49621
llvm-svn: 338776
Summary:
Code now exists to track number of mutations that are used in fuzzing in total
and ones that produce new coverage. The stats are currently being dumped to the
command line.
Patch by Kodé Williams (@kodewilliams).
Reviewers: metzman, Dor1s, morehouse, kcc
Reviewed By: Dor1s, morehouse, kcc
Subscribers: delcypher, kubamracek, kcc, morehouse, llvm-commits, #sanitizers, mgorny
Differential Revision: https://reviews.llvm.org/D48054
llvm-svn: 337324
This is a fix for bug 37047.
https://bugs.llvm.org/show_bug.cgi?id=37047
Implemented by basically reversing the logic. Previously all strings
were considered, with some operations excluded. Now strings are excluded
by default, and only strings during the CB considered.
Patch By: pdknsk
Differential Revision: https://reviews.llvm.org/D48800
llvm-svn: 337296
Summary:
Code now exists to track number of mutations that are used in fuzzing in total
and ones that produce new coverage. The stats are currently being dumped to the
command line.
Patch by Kodé Williams (@kodewilliams).
Reviewers: metzman, Dor1s, morehouse, kcc
Reviewed By: Dor1s, morehouse, kcc
Subscribers: delcypher, kubamracek, kcc, morehouse, llvm-commits, #sanitizers, mgorny
Differential Revision: https://reviews.llvm.org/D48054
llvm-svn: 337194
Code now exists to track number of mutations that are used in fuzzing in
total and ones that produce new coverage. The stats are currently being
dumped to the command line.
Patch By: Kode Williams
Differntial Revision: https://reviews.llvm.org/D48054
llvm-svn: 336597
It doesn't make sense to non-deterministically choose between
`CopyPart(..)` and `InsertPart(..)` when it is known that
`InsertPart(..)` will fail.
This upstream's a change from JFS solver's fork of LibFuzzer.
Differential Revision: https://reviews.llvm.org/D45693
llvm-svn: 330687
Resulting library binaries will be named libclang_rt.fuzzer*, and will
be placed in Clang toolchain, allowing redistribution.
Differential Revision: https://reviews.llvm.org/D36908
llvm-svn: 311407