Commit Graph

40 Commits

Author SHA1 Message Date
Matt Morehouse 1c8e05110c [libFuzzer] Remove lazy counters.
Summary: Lazy counters haven't improved performance for large fuzz targets.

Reviewers: kcc

Reviewed By: kcc

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67476

llvm-svn: 373403
2019-10-01 22:49:06 +00:00
Kostya Serebryany db88fc56b9 [libFuzzer] implement a better queue for the fork mode. Add an internal flag -stop_file to allow graceful shutdown of fuzzing. Enhance the logging in the fork mode
llvm-svn: 363470
2019-06-14 22:56:50 +00:00
Kostya Serebryany b7cc3d9953 [libFuzzer] automatically collect the data flow trace (DFT) in the fork mode if -collect_data_flow= is given
llvm-svn: 361448
2019-05-23 00:22:46 +00:00
Kostya Serebryany 4614cc3dfd [libFuzzer] add -features_dir= flag to dump unique input features on disk
llvm-svn: 358317
2019-04-13 00:20:31 +00:00
Kostya Serebryany 9982ee5472 [libFuzzer] form mode: add -ignore_crashes flag, honor the max_total_time flag, print the number of ooms/timeouts/crashes, fix a typo
llvm-svn: 354175
2019-02-15 21:51:15 +00:00
Kostya Serebryany cdbb9dc962 [libFuzzer] teach the fork mode to ignore OOMs and timeouts
llvm-svn: 353792
2019-02-12 02:18:53 +00:00
Kostya Serebryany 0fda9dcbe9 [libFuzzer] more refactoring; change some of the exit codes (timeout, OOM, interrupt) so that the parent process can distinguish those
llvm-svn: 353584
2019-02-09 00:16:21 +00:00
Kostya Serebryany 8da9479e40 [libFuzzer] experimental performance optimization -lazy_counters, off by default. Posix-only for now, tested on Linux
llvm-svn: 352700
2019-01-31 00:09:43 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
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
2019-01-19 08:50:56 +00:00
Jonathan Metzman 9e14cccf6f [libFuzzer] Remove unstable edge handling
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
2019-01-15 22:12:51 +00:00
Max Moroz 8c95b48ba2 [libFuzzer] Remove mutation stats and weighted mutation selection.
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
2018-08-29 21:53:15 +00:00
Max Moroz 5a9baa330c [libFuzzer] Initial implementation of weighted mutation leveraging during runtime.
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
2018-08-02 22:30:03 +00:00
Max Moroz 1e954f78d1 [libFuzzer] Handle unstable edges by using minimum hit counts
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
2018-07-23 14:20:52 +00:00
Max Moroz 061b4af998 [libFuzzer] Mutation tracking and logging implemented.
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
2018-07-17 20:37:40 +00:00
Max Moroz 5697c59c7f Revert r337194 (https://reviews.llvm.org/D48891) due to compilation errors.
llvm-svn: 337206
2018-07-16 20:05:18 +00:00
Max Moroz 8a5083df53 [libFuzzer] Mutation tracking and logging implemented.
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
2018-07-16 17:50:46 +00:00
Max Moroz 08dad54924 [libFuzzer] Implement stat::stability_rate based on the percentage of unstable edges.
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
2018-07-16 16:01:31 +00:00
Max Moroz 1d369a5d01 Revert r337175 (https://reviews.llvm.org/D49212) due to unintentional format changes.
llvm-svn: 337180
2018-07-16 15:15:34 +00:00
Max Moroz 2156d885e0 [libFuzzer] Implement stat::stability_rate based on the percentage of unstable edges.
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
2018-07-16 14:54:23 +00:00
Matt Morehouse a5bb6d53f2 Revert "[libFuzzer] Mutation tracking and logging implemented"
This reverts r336597 due to bot breakage.

llvm-svn: 336616
2018-07-09 22:31:26 +00:00
Matt Morehouse d153d46884 [libFuzzer] Mutation tracking and logging implemented
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
2018-07-09 20:17:52 +00:00
Kostya Serebryany 51ddb88300 [libFuzzer] add one more value profile metric, under a flag (experimental)
llvm-svn: 336234
2018-07-03 22:33:09 +00:00
Kostya Serebryany 4d9fd7a266 [libFuzzer] remove an experimental flag -use_feature_frequency
llvm-svn: 334146
2018-06-06 23:24:41 +00:00
Kostya Serebryany 1fd005f552 [libFuzzer] initial implementation of -data_flow_trace. It parses the data flow trace and prints the summary, but doesn't use the information in any other way yet
llvm-svn: 334058
2018-06-06 01:23:29 +00:00
Kostya Serebryany 69c2b71a51 [libFuzzer] reinstate -dump_coverage, which is still in use (reverts r332036)
llvm-svn: 332876
2018-05-21 19:47:00 +00:00
Kostya Serebryany e9c6f06cce [libFuzzer] add an experimental flag -focus_function: libFuzzer will try to focus on inputs that trigger that function
llvm-svn: 332554
2018-05-16 23:26:37 +00:00
Kostya Serebryany d80e821646 [libFuzzer] remove the dump_coverage flag, it hasn't been working with the inline sanitizer coverage anyway
llvm-svn: 332036
2018-05-10 20:24:39 +00:00
Kostya Serebryany 59bf1e8b36 [libFuzzer] remove the experimental support for clang coverage instrumentation. This mode has not been used and our experiments with https://github.com/google/fuzzer-test-suite show that this signal is weaker than the SanitizerCoverage
llvm-svn: 332034
2018-05-10 20:12:15 +00:00
Matt Morehouse 36c89b3c77 [libFuzzer] Set -experimental_len_control=1000 as default.
Summary:
Experiments using
https://github.com/google/fuzzer-test-suite/tree/master/engine-comparison
show a significant increase in coverage and reduction in corpus size
with this option enabled.

Addresses https://llvm.org/pr36371.

Reviewers: kcc

Reviewed By: kcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42932

llvm-svn: 325050
2018-02-13 20:52:15 +00:00
Kostya Serebryany 2659c63e2e [libFuzzer] honor -use_counters, sligntly change the meaning of -experimental_len_control, call UpdateFeatureFrequency only if instructed by the flag
llvm-svn: 320205
2017-12-08 22:21:42 +00:00
Kostya Serebryany de9bafb162 [libFuzzer] add a flag -malloc_limit_mb
llvm-svn: 319590
2017-12-01 22:12:04 +00:00
Kostya Serebryany 6afa7a54be [libFuzzer] remove stale flags; NFC
llvm-svn: 319572
2017-12-01 19:24:06 +00:00
Kostya Serebryany ad05ee0512 [libFuzzer] add an experimental search heuristic flag -reduce_depth
llvm-svn: 319571
2017-12-01 19:18:38 +00:00
Kostya Serebryany a2ca2dcc46 [libFuzzer] handle SIGUSR1/SIGUSR2 and try to exit grafully on these signals
llvm-svn: 317829
2017-11-09 20:30:19 +00:00
Alex Shlyapnikov 6f1c26f222 [libFuzzer] Periodically purge allocator's quarantine to prolong fuzzing sessions.
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
2017-10-23 22:04:30 +00:00
Kostya Serebryany 4083d54675 [libFuzzer] experimental flag to tweak the corpus distribution. Seems to improve the situation dramatically on the png benchmark and make things worse on a number of micro-puzzles. Needs more A/B testing
llvm-svn: 315407
2017-10-11 01:44:26 +00:00
Max Moroz 330496c3fc [libFuzzer] Disable experimental clang coverage support by default.
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
2017-10-05 22:41:03 +00:00
Kostya Serebryany c07008653c [libFuzzer] allow -print_funcs=N: N is the max number of new covered function printed
llvm-svn: 311945
2017-08-28 22:52:22 +00:00
Kostya Serebryany 2eef816e6e [libFuzzer] add -print_funcs=1 (on bey default): print newly discovered functions during fuzzing
llvm-svn: 311797
2017-08-25 20:09:25 +00:00
George Karpenkov 10ab2ace13 Move libFuzzer to compiler_rt.
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
2017-08-21 23:25:50 +00:00