to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
Remove code for handling unstable edges from libFuzzer since
it has not been found useful.
Differential Revision: https://reviews.llvm.org/D56730
llvm-svn: 351262
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:
We only run the 3rd check if 2nd check finds unstable edges.
3rd UpdateUnstableCounters is now merged with ApplyUnstableCounters to only run 1 iteration.
Patch by Kyungtak Woo (@kevinwkt).
Reviewers: Dor1s, metzman, morehouse
Reviewed By: Dor1s, morehouse
Subscribers: delcypher, #sanitizers, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D50411
llvm-svn: 339249
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:
Added a new mode within flag -handle_unstable for new unstable handling algorithm that does the following:
When an edge is shown as unstable, copy to UnstableCounters the value 0.
During ApplyUnstableCounters we copy back the value 0 to ModuleInline8bitCounters if the edge was unstable.
This way we would be ignoring completely features that were collected through non-determinism.
Unstable hits would be counted as if it never hit.
Reviewers: metzman, Dor1s, kcc, morehouse
Reviewed By: metzman, morehouse
Subscribers: delcypher, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D49684
llvm-svn: 337853
Summary:
Created unstable_handle flag that takes 1 or 2, depending on the handling type.
Modified RunOne to accommodate the following heuristic:
Use the first CollectFeatures to count how many features there are.
If no new features, CollectFeatures like before.
If there is new feature, we run CB 2 more times,
Check which edges are unstable per input and we store the least amount of hit counts for each edge.
Apply these hit counts back to inline8bitcounters so that CollectFeatures can work as intended.
Modified UnstableCounters to 8int_t and created a bitset UnstableSet to tell which edges are unstable.
Patch by Kyungtak Woo (@kevinwkt).
Reviewers: Dor1s, metzman, morehouse
Reviewed By: Dor1s, morehouse
Subscribers: delcypher, #sanitizers, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D49525
llvm-svn: 337696
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
Summary:
Created a -print_unstable_stats flag.
When -print_unstable_stats=1, we run it 2 more times on interesting inputs poisoning unstable edges in an array.
On program termination, we run PrintUnstableStats() which will print a line with a stability percentage like AFL does.
Patch by Kyungtak Woo (@kevinwkt).
Reviewers: metzman, Dor1s, kcc, morehouse
Reviewed By: metzman, Dor1s, morehouse
Subscribers: delcypher, llvm-commits, #sanitizers, kcc, morehouse, Dor1s
Differential Revision: https://reviews.llvm.org/D49212
llvm-svn: 337187
Summary:
Created a -print_unstable_stats flag.
When -print_unstable_stats=1, we run it 2 more times on interesting inputs poisoning unstable edges in an array.
On program termination, we run PrintUnstableStats() which will print a line with a stability percentage like AFL does.
Patch by Kyungtak Woo (@kevinwkt).
Reviewers: metzman, Dor1s, kcc, morehouse
Reviewed By: metzman, Dor1s, morehouse
Subscribers: delcypher, llvm-commits, #sanitizers, kcc, morehouse, Dor1s
Differential Revision: https://reviews.llvm.org/D49212
llvm-svn: 337175
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
Summary:
The most common usecase for -runs=0 is for generating code coverage
over some corpus. Coverage reports based on sancov are about to be deprecated,
which means some external coverage solution will be used, e.g. Clang source
based code coverage, which does not use any sancov instrumentations and thus
libFuzzer would consider any input to be not interesting in that case.
Reviewers: kcc
Reviewed By: kcc
Subscribers: alex, delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D47271
llvm-svn: 333116
Summary:
When out-of-memory or timeout occurs, threads can be stopped during
symbolization, thereby causing a deadlock when the OOM/TO handlers
attempt symbolization. We avoid this deadlock by skipping symbolization
if another thread is symbolizing.
Reviewers: kcc
Reviewed By: kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46605
llvm-svn: 331825
Short-circuiting causes tests to fail on Mac since libFuzzer crashes
rather than exiting with an error code when an unexpected signal
happens.
llvm-svn: 331324
Summary:
Fixes https://github.com/google/sanitizers/issues/788/, a deadlock
caused by multiple crashes happening at the same time. Before printing
a crash report, we now test and set an atomic flag. If the flag was
already set, the crash handler returns immediately.
Reviewers: kcc
Reviewed By: kcc
Subscribers: llvm-commits, kubamracek
Differential Revision: https://reviews.llvm.org/D46277
llvm-svn: 331310
This is needed in case the users of libFuzzer use libc++ in their
code, which the fuzz target (libFuzzer) will be linked against.
When libc++ source is available, we build a private version of it
and link it against libFuzzer which allows using the same static
library against codebases which use both libc++ and libstdc++.
Differential Revision: https://reviews.llvm.org/D37631
llvm-svn: 322755
This is needed in case the users of libFuzzer use libc++ in their
code, which the fuzz target (libFuzzer) will be linked against.
When libc++ source is available, we build a private version of it
and link it against libFuzzer which allows using the same static
library against codebases which use both libc++ and libstdc++.
Differential Revision: https://reviews.llvm.org/D37631
llvm-svn: 322604
Fails on darwin
Revert "[fuzzer] Script to detect unbalanced allocation in -trace_malloc output"
Needs previous one.
This reverts commit r317034, r317036.
llvm-svn: 317061
Summary: The result of clang-format and few manual changes (as prompted on D39155).
Reviewers: vitalybuka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39211
llvm-svn: 316395
Summary:
Fuzzing targets that allocate/deallocate a lot of memory tend to consume
a lot of RSS when ASan quarantine is enabled. Purging quarantine between
iterations and returning memory to OS keeps RSS down and should not
reduce the quarantine effectiveness provided the fuzz target does not
preserve state between iterations (in this case this feature can be turned off).
Based on D39153.
Reviewers: vitalybuka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39155
llvm-svn: 316382
Summary:
It can be enabled via "-use_clang_coverage=1" flag. Reason for disabling:
libFuzzer resets Clang Counters and makes it impossible to generate coverage
report for a regular fuzz target (i.e. not standalone build).
Reviewers: kcc
Reviewed By: kcc
Subscribers: kcc
Differential Revision: https://reviews.llvm.org/D38604
llvm-svn: 315029
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
Kostya Serebryany