Commit Graph

73 Commits

Author SHA1 Message Date
Yuanfang Chen 4caeb62e51 [Fuzzer] Rename ExecuteCommandWithPopen to ExecuteCommandNon-Fushsia target will keep using popen/pclose implementation. OnFuchsia, Two-args version of `ExecuteCommand` is a simple wrapper of theone-arg version. (Hopefully) Fix D73329 build on Fuchsia. 2020-02-12 16:03:55 -08:00
Yuanfang Chen 4f3c3bbbf8 Reland "[NFC][libFuzzer] Prefix TempPath with string showing the work it is doing."
With fix (somehow one hunk is missed).
2020-02-10 18:23:39 -08:00
Yuanfang Chen b1c7623982 Revert "[NFC][libFuzzer] Prefix TempPath with string showing the work it is doing."
This reverts commit 8a29cb4421.

fuzzer-linux bot has failure because of this.
2020-02-10 18:06:17 -08:00
Yuanfang Chen 8a29cb4421 [NFC][libFuzzer] Prefix TempPath with string showing the work it is doing. 2020-02-10 16:45:10 -08:00
Yuanfang Chen 85515c7fd5 [libFuzzer] communicate through pipe to subprocess for MinimizeCrashInput
For CleanseCrashInput, discards stdout output anyway since it is not used.

These changes are to defend against aggressive PID recycle on windows to reduce the chance of contention on files.

Using pipe instead of file also workaround the problem that when the
process is spawned by llvm-lit, the aborted process keeps a handle to the
output file such that the output file can not be removed. This will
cause random test failures.

https://devblogs.microsoft.com/oldnewthing/20110107-00/?p=11803

Reviewers: kcc, vitalybuka

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D73329
2020-02-10 16:45:10 -08:00
Max Moroz 15f1d5d144 [libFuzzer] Add INFO output when LLVMFuzzerCustomMutator is found.
Summary:
there is an ongoing work on interchangeable custom mutators
(https://github.com/google/clusterfuzz/pull/1333/files#r367706283)
and having some sort of signalling from libFuzzer that it has loaded
a custom mutator would be helpful.

The initial idea was to make the mutator to print something, but given
the anticipated variety of different mutators, it does not seem possible
to make all of them print the same message to signal their execution.

Reviewers: kcc, metzman

Reviewed By: metzman

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D73136
2020-01-22 12:56:16 -08:00
Jonathan Metzman 23bee0b0cf [fuzzer] Add basic support for emscripten.
Summary:
Add basic support for emscripten.

This enables libFuzzer to build (using build.sh) for emscripten and fuzz
a target compiled with
-fsanitize-coverage=inline-8bit-counters.

Basic fuzzing and bug finding work with this commit.
RSS limit and timeouts will not work because they depend on system
functions that are not implemented/widely supported in emscripten.

Reviewers: kcc, vitalybuka, hctim

Reviewed By: hctim

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D71285
2019-12-12 08:56:47 -08:00
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
Max Moroz 0784e01a98 [libFuzzer] Disable len_control by default if LLVMFuzzerCustomMutator is used.
Summary:
Some custom mutators may not peform well when size restriction is
enforced by len_control. Because of that, it's safer to disable len_control
by default in such cases, but still allow users to enable it manually.
Bug example: https://bugs.chromium.org/p/chromium/issues/detail?id=919530.

Tested manually with LPM-based and regular fuzz targets.

Reviewers: kcc, vitalybuka, metzman

Reviewed By: kcc, metzman

Subscribers: delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D63334

llvm-svn: 363443
2019-06-14 19:34:11 +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 4c7353c53b [libFuzzer] code refactoring; NFC
llvm-svn: 360400
2019-05-10 01:34:26 +00:00
Kostya Serebryany da96d92175 [libFuzzer] small refactoring in the driver; dummy implementation of collect_data_flow; attempt to fix the windows bot
llvm-svn: 360399
2019-05-10 00:59:32 +00:00
Jonathan Metzman f3ee97731e [libFuzzer] Replace -seed_corpus to better support fork mode on Win
Summary:
Pass seed corpus list in a file to get around argument length limits on Windows.
This limit was preventing many uses of fork mode on Windows.

Reviewers: kcc, morehouse

Reviewed By: kcc

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D60980

llvm-svn: 359610
2019-04-30 20:56:18 +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 8c2791469d [libFuzzer] when doing the merge, keep track of the coveraged edges, not just features
llvm-svn: 354087
2019-02-15 00:08:16 +00:00
Kostya Serebryany 60c5ded269 [libFuzzer] add threads to the fork mode: now you can pass -fork=N to run N concurrent workers. Fork mode is still work-in-progress.
llvm-svn: 353997
2019-02-14 00:25:43 +00:00
Kostya Serebryany 5c08e811de [libFuzzer] move the implementation of the fork mode into a separate file
llvm-svn: 353891
2019-02-12 22:48:55 +00:00
Kostya Serebryany 2b9a8f37a4 [libFuzzer] make the fork mode less verbose
llvm-svn: 353794
2019-02-12 03:12:40 +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 63f48717b5 [libFuzzer] extend the -fork=1 functionality. Still not fully usable, but good enough for the first unit test
llvm-svn: 353775
2019-02-12 00:12:33 +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 114cfafe05 [libFuzzer] refactor the merging code, NFC
llvm-svn: 353576
2019-02-08 22:59:03 +00:00
Kostya Serebryany b1e8b8149b [libFuzzer] remove two unused experimental flags
llvm-svn: 353573
2019-02-08 22:02:37 +00:00
Kostya Serebryany f762a11544 [libFuzzer] introduce an experimental mode -fork=1, where fuzzing happens in a subprocess (still running multiple inputs per process), thus making the fuzzing more resilient to timeouts and OOMs. This is just a skeleton of the code, and some associated refactoring, not a fully working feature yet.
llvm-svn: 353570
2019-02-08 21:27:23 +00:00
Kostya Serebryany 0719b3527f [libFuzzer] refactor the way we choose the element to cross-over with, NFC (expected1); add a flag -seed_inputs= to pass extra seed inputs as file paths, not dirs
llvm-svn: 353494
2019-02-08 01:20:54 +00:00
Kostya Serebryany 23482e1d07 [libFuzzer] set libFuzzer's own SEGV handler even one is already present, but call that handler from ours (unless we are unprotecting lazy counters). Call ProtectLazyCounters later, so that it runs after the initialization code in the target.
llvm-svn: 352713
2019-01-31 01:40:14 +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
Kostya Serebryany 5c0751ec3e [libFuzzer] remove stale code, NFC
llvm-svn: 352604
2019-01-30 06:21:20 +00:00
Kostya Serebryany 2891b257c2 [libFuzzer] remove stale code
llvm-svn: 352571
2019-01-29 23:53:28 +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 b795c31dff [libFuzzer][MSVC] Make attribute-use compatible with MSVC
Summary:
Replace attributes with macros that use equivalent declspecs
for MSVC.

Reviewers: vitalybuka

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D56512

llvm-svn: 351456
2019-01-17 16:36:05 +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 8db0befc6d [libFuzzer] Handle unstable edges by disregarding unstable edges
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
2018-07-24 21:02:44 +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 a34c65e845 [libFuzzer] Make -fsanitize=memory,fuzzer work.
This patch allows libFuzzer to fuzz applications instrumented with MSan
without recompiling libFuzzer with MSan instrumentation.

Fixes https://github.com/google/sanitizers/issues/958.

Differential Revision: https://reviews.llvm.org/D48891

llvm-svn: 336619
2018-07-09 23:51:08 +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 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