Commit Graph

66 Commits

Author SHA1 Message Date
Kazuaki Ishizaki a1e7e401d2 [compiler-rt] NFC: Fix trivial typo
Reviewed By: xgupta

Differential Revision: https://reviews.llvm.org/D77457
2021-09-04 14:12:58 +05:30
Kostya Serebryany 7c921753e0 [libFuzzer] replace Vector/Set with std::vector/std::set. The custom names are not required any more since we now build with a private version of libc++. Fix some of the 81+ character lines. Mechanical change, NFC expected.
[libFuzzer] replace Vector/Set with std::vector/std::set.

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D107374
2021-08-03 11:31:04 -07:00
Marco Vanotti c5d725172d Revert "Refactor mutation strategies into a standalone library"
This reverts commit 361f742f16.
2021-07-02 09:45:11 -07:00
Aaron Green 361f742f16 Refactor mutation strategies into a standalone library
This change introduces libMutagen/libclang_rt.mutagen.a as a subset of libFuzzer/libclang_rt.fuzzer.a. This library contains only the fuzzing strategies used by libFuzzer to produce new test inputs from provided inputs, dictionaries, and SanitizerCoverage feedback.

Most of this change is simply moving sections of code to one side or the other of the library boundary. The only meaningful new code is:

* The Mutagen.h interface and its implementation in Mutagen.cpp.
* The following methods in MutagenDispatcher.cpp:
  * UseCmp
  * UseMemmem
  * SetCustomMutator
  * SetCustomCrossOver
  * LateInitialize (similar to the MutationDispatcher's original constructor)
  * Mutate_AddWordFromTORC (uses callbacks instead of accessing TPC directly)
  * StartMutationSequence
  * MutationSequence
  * DictionaryEntrySequence
  * RecommendDictionary
  * RecommendDictionaryEntry
* FuzzerMutate.cpp (which now justs sets callbacks and handles printing)
* MutagenUnittest.cpp (which adds tests of Mutagen.h)

A note on performance: This change was tested with a 100 passes of test/fuzzer/LargeTest.cpp with 1000 runs per pass, both with and without the change. The running time distribution was qualitatively similar both with and without the change, and the average difference was within 30 microseconds (2.240 ms/run vs 2.212 ms/run, respectively). Both times were much higher than observed with the fully optimized system clang (~0.38 ms/run), most likely due to the combination of CMake "dev mode" settings (e.g. CMAKE_BUILD_TYPE="Debug", LLVM_ENABLE_LTO=OFF, etc.). The difference between the two versions built similarly seems to be "in the noise" and suggests no meaningful performance degradation.

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D102447
2021-07-02 09:20:23 -07:00
Matt Morehouse fd0a2f75ff Revert "Refactor mutation strategies into a standalone library"
This reverts commit c4a41cd77c due to
buildbot failure.
2021-05-26 15:16:43 -07:00
Aaron Green c4a41cd77c Refactor mutation strategies into a standalone library
This change introduces libMutagen/libclang_rt.mutagen.a as a subset of libFuzzer/libclang_rt.fuzzer.a. This library contains only the fuzzing strategies used by libFuzzer to produce new test inputs from provided inputs, dictionaries, and SanitizerCoverage feedback.

Most of this change is simply moving sections of code to one side or the other of the library boundary. The only meaningful new code is:

* The Mutagen.h interface and its implementation in Mutagen.cpp.
* The following methods in MutagenDispatcher.cpp:
  * UseCmp
  * UseMemmem
  * SetCustomMutator
  * SetCustomCrossOver
  * LateInitialize (similar to the MutationDispatcher's original constructor)
  * Mutate_AddWordFromTORC (uses callbacks instead of accessing TPC directly)
  * StartMutationSequence
  * MutationSequence
  * DictionaryEntrySequence
  * RecommendDictionary
  * RecommendDictionaryEntry
* FuzzerMutate.cpp (which now justs sets callbacks and handles printing)
* MutagenUnittest.cpp (which adds tests of Mutagen.h)

A note on performance: This change was tested with a 100 passes of test/fuzzer/LargeTest.cpp with 1000 runs per pass, both with and without the change. The running time distribution was qualitatively similar both with and without the change, and the average difference was within 30 microseconds (2.240 ms/run vs 2.212 ms/run, respectively). Both times were much higher than observed with the fully optimized system clang (~0.38 ms/run), most likely due to the combination of CMake "dev mode" settings (e.g. CMAKE_BUILD_TYPE="Debug", LLVM_ENABLE_LTO=OFF, etc.). The difference between the two versions built similarly seems to be "in the noise" and suggests no meaningful performance degradation.

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D102447
2021-05-26 13:27:49 -07:00
Aaron Green 6708186c91 [crt][fuzzer] Fix up various numeric conversions
Attempting to build a standalone libFuzzer in Fuchsia's default toolchain for the purpose of cross-compiling the unit tests  revealed a number of not-quite-proper type conversions. Fuchsia's toolchain include `-std=c++17` and `-Werror`, among others, leading to many errors like `-Wshorten-64-to-32`, `-Wimplicit-float-conversion`, etc.

Most of these have been addressed by simply making the conversion explicit with a `static_cast`. These typically fell into one of two categories: 1) conversions between types where high precision isn't critical, e.g. the "energy" calculations for `InputInfo`, and 2) conversions where the values will never reach the bits being truncated, e.g. `DftTimeInSeconds` is not going to exceed 136 years.

The major exception to this is the number of features: there are several places that treat features as `size_t`, and others as `uint32_t`. This change makes the decision to cap the features at 32 bits. The maximum value of a feature as produced by `TracePC::CollectFeatures` is roughly:
  (NumPCsInPCTables + ValueBitMap::kMapSizeInBits + ExtraCountersBegin() - ExtraCountersEnd() + log2(SIZE_MAX)) * 8

It's conceivable for extremely large targets and/or extra counters that this limit could be reached. This shouldn't break fuzzing, but it will cause certain features to collide and lower the fuzzers overall precision. To address this, this change adds a warning to TracePC::PrintModuleInfo about excessive feature size if it is detected, and recommends refactoring the fuzzer into several smaller ones.

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D97992
2021-03-11 16:01:28 -08:00
Max Moroz dc62d5ec97 [libFuzzer] Added -print_full_coverage flag.
-print_full_coverage=1 produces a detailed branch coverage dump when run on a single file.
Uses same infrastructure as -print_coverage flag, but prints all branches (regardless of coverage status) in an easy-to-parse format.
Usage: For internal use with machine learning fuzzing models which require detailed coverage information on seed files to generate mutations.

Differential Revision: https://reviews.llvm.org/D85928
2020-10-23 16:05:54 -07:00
Dokyung Song 226866e115 [libFuzzer] Separate platform related macros out from FuzzerDefs.h into FuzzerPlatform.h, and adjust includes in other files.
Summary: This patch separates platform related macros in lib/fuzzer/FuzzerDefs.h into lib/fuzzer/FuzzerPlatform.h, and use FuzzerPlatform.h where necessary. This separation helps when compiling libFuzzer's interceptor module (under review); an unnecessary include of standard headers (such as string.h) may produce conflicts/ambiguation with the interceptor's declarations/definitions of library functions, which complicates interceptor implementation.

Reviewers: morehouse, hctim

Reviewed By: morehouse

Subscribers: krytarowski, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D83805
2020-07-14 21:31:56 +00:00
Max Moroz ad7b908b4e [libFuzzer] Make dataflow and focus functions more user friendly.
Summary:
- Fail loudly if SetFocusFunction failed when it should not. For more info see
  - https://github.com/google/oss-fuzz/issues/3311
  - https://github.com/google/sanitizers/issues/1190
- Fail loudly if CollectDataFlow is called without seed corpus.

Reviewers: kcc, metzman

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D73813
2020-02-03 08:36:03 -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
Nico Weber 65492d959b compiler-rt: Rename .cc file in lib/sanitizer_common to .cpp
See https://reviews.llvm.org/D58620 for discussion, and for the commands
I ran. In addition I also ran

  for f in $(svn diff | diffstat | grep .cc | cut -f 2 -d ' '); do rg $f . ; done

and manually updated (many) references to renamed files found by that.

llvm-svn: 367463
2019-07-31 18:51:27 +00:00
Kostya Serebryany 4a5793f7d0 [libFuzzer] perform more agressive value profiling in memcmp
llvm-svn: 360385
2019-05-09 22:09:25 +00:00
Kostya Serebryany 77cbc62544 [libFuzzer] print new functions as they are discovered in the fork mode
llvm-svn: 354092
2019-02-15 01:22:00 +00:00
Kostya Serebryany 96f81bc679 [libFuzzer] when doing the merge, keep track of the coveraged edges, not just features
llvm-svn: 354076
2019-02-14 23:12:33 +00:00
Kostya Serebryany 56b2d57cbf [libFuzzer] simplify the code for print_coverage=1 so that it doesn't fail on broken debug info
llvm-svn: 353781
2019-02-12 00:52:11 +00:00
Jonathan Metzman fc7faecb40 [fuzzer] Use RawPrint instead of Printf for instrumentation warning
Summary:
Use RawPrint instead of Printf for instrumentation warning because
Printf doesn't work on Win when instrumentation is being
initialized (since OutputFile is not yet initialized).

Reviewers: kcc

Reviewed By: kcc

Differential Revision: https://reviews.llvm.org/D57531

llvm-svn: 352789
2019-01-31 20:32:20 +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 6fd4d8ab9c [libFuzzer] refactor the handling of instrumentation counters so that they are grouped in regions one full page each. Needed for future optimization. NFC
llvm-svn: 352603
2019-01-30 06:15:52 +00:00
Kostya Serebryany 2891b257c2 [libFuzzer] remove stale code
llvm-svn: 352571
2019-01-29 23:53:28 +00:00
Kostya Serebryany 035c08f73d [libFuzzer] revert an accidental commit
llvm-svn: 352567
2019-01-29 23:41:50 +00:00
Kostya Serebryany 62d7270610 [libFuzzer] remove deprecated support for -fsanitize-coverage=trace-pc[-guard]
llvm-svn: 352566
2019-01-29 23:40:05 +00:00
Kostya Serebryany 50a1c69712 [libFuzzer] remove deprecated support for -fsanitize-coverage=trace-pc[-guard]
llvm-svn: 352564
2019-01-29 23:37:20 +00:00
Kostya Serebryany bb01a098b1 [libFuzzer] print uncovered functions when doing -print_coverage=1
llvm-svn: 352263
2019-01-26 01:33:09 +00:00
Kostya Serebryany 360bf5ff58 [libFuzzer] more agressive value profiling and CMP tracing for switch statements
llvm-svn: 352107
2019-01-24 21:08:54 +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
Jonathan Metzman 55ddb2c790 [libfuzzer][MSVC] Make calls to builtin functions work with MSVC
Summary:
Replace calls to builtin functions with macros or functions that call the
Windows-equivalents when targeting windows and call the original
builtin functions everywhere else.
This change makes more parts of libFuzzer buildable with MSVC.

Reviewers: vitalybuka

Reviewed By: vitalybuka

Subscribers: mgorny, rnk, thakis

Differential Revision: https://reviews.llvm.org/D56439

llvm-svn: 350766
2019-01-09 21:46:09 +00:00
George Karpenkov f28523bb3f [libFuzzer] Generalize the code for getting the previous offset for different architectures
Without this change, tests in coverage.test and dump_coverage.test are
failing on non-x86_64 platforms.
The diff is copied from sanitizer_common library, an alternative would
be to link it together with libFuzzer.

Differential Revision: https://reviews.llvm.org/D53040

llvm-svn: 344104
2018-10-10 00:57:44 +00:00
Matt Morehouse 7e042bb1d1 [libFuzzer] Port to Windows
Summary:
Port libFuzzer to windows-msvc.
This patch allows libFuzzer targets to be built and run on Windows, using -fsanitize=fuzzer and/or fsanitize=fuzzer-no-link. It allows these forms of coverage instrumentation to work on Windows as well.
It does not fix all issues, such as those with -fsanitize-coverage=stack-depth, which is not usable on Windows as of this patch.
It also does not fix any libFuzzer integration tests. Nearly all of them fail to compile, fixing them will come in a later patch, so libFuzzer tests are disabled on Windows until them.

Patch By: metzman

Reviewers: morehouse, rnk

Reviewed By: morehouse, rnk

Subscribers: #sanitizers, delcypher, morehouse, kcc, eraman

Differential Revision: https://reviews.llvm.org/D51022

llvm-svn: 341082
2018-08-30 15:54:44 +00:00
Matt Morehouse cf311cfc20 Revert "[libFuzzer] Port to Windows"
This reverts r340949 due to bot breakage again.

llvm-svn: 340954
2018-08-29 18:40:41 +00:00
Matt Morehouse 245ebd71ef [libFuzzer] Port to Windows
Summary:
Port libFuzzer to windows-msvc.
This patch allows libFuzzer targets to be built and run on Windows, using -fsanitize=fuzzer and/or fsanitize=fuzzer-no-link. It allows these forms of coverage instrumentation to work on Windows as well.
It does not fix all issues, such as those with -fsanitize-coverage=stack-depth, which is not usable on Windows as of this patch.
It also does not fix any libFuzzer integration tests. Nearly all of them fail to compile, fixing them will come in a later patch, so libFuzzer tests are disabled on Windows until them.

Reviewers: morehouse, rnk

Reviewed By: morehouse, rnk

Subscribers: #sanitizers, delcypher, morehouse, kcc, eraman

Differential Revision: https://reviews.llvm.org/D51022

llvm-svn: 340949
2018-08-29 18:08:34 +00:00
Matt Morehouse bab8556f01 Revert "[libFuzzer] Port to Windows"
This reverts commit r340860 due to failing tests.

llvm-svn: 340867
2018-08-28 19:07:24 +00:00
Matt Morehouse c6fff3b6f5 [libFuzzer] Port to Windows
Summary:
Port libFuzzer to windows-msvc.
This patch allows libFuzzer targets to be built and run on Windows, using -fsanitize=fuzzer and/or fsanitize=fuzzer-no-link. It allows these forms of coverage instrumentation to work on Windows as well.
It does not fix all issues, such as those with -fsanitize-coverage=stack-depth, which is not usable on Windows as of this patch.
It also does not fix any libFuzzer integration tests. Nearly all of them fail to compile, fixing them will come in a later patch, so libFuzzer tests are disabled on Windows until them.

Patch By: metzman

Reviewers: morehouse, rnk

Reviewed By: morehouse, rnk

Subscribers: morehouse, kcc, eraman

Differential Revision: https://reviews.llvm.org/D51022

llvm-svn: 340860
2018-08-28 18:34:32 +00:00
Max Moroz cd02f3147b [libFuzzer] Optimize handle unstable checks by reducing iterations
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
2018-08-08 14:32:46 +00:00
Max Moroz 84a48271d4 [libFuzzer] Add unstable function printing to print_unstable_stats flag
Summary:
There may be cases in which a user wants to know which part of their code is unstable.
We use ObservedFuncs and UnstableCounters to print at exit which of the ObservedFunctions
are unstable under the -print_unstable_stats flag.

Patch by Kyungtak Woo (@kevinwkt).

Reviewers: Dor1s, metzman, morehouse

Reviewed By: Dor1s, metzman, morehouse

Subscribers: delcypher, #sanitizers, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D50264

llvm-svn: 339081
2018-08-06 23:14:13 +00:00
Kostya Serebryany cedebd5940 [libFuzzer] use absolute distance in addition to the hamming distance in value profiling; our A/B testing have (somewhat weak) indication that this provides an additional signal for corpus expansion
llvm-svn: 338661
2018-08-02 00:24:49 +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
Kostya Serebryany 44edc281d9 [libFuzzer] when -print_coverage=1 is given, print more stats (the number of seeds that hit every given function)
llvm-svn: 337501
2018-07-19 22:00:48 +00:00
Max Moroz 42b54e8117 [libFuzzer] Create single template for visiting Inline8bitCounters
Summary:
Created IterateInline8bitCounters, a single template for visiting  Inline8bitCounters (nested for loop)
Made InitializeUnstableCounters and UpdateUnstableCounters both send a lambda to IterateInline8bitCounters.

Patch by Kyungtak Woo (@kevinwkt).

Reviewers: Dor1s, metzman, kcc, morehouse

Reviewed By: metzman, morehouse

Subscribers: delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D49453

llvm-svn: 337403
2018-07-18 17:03:27 +00:00
Matt Morehouse 43a2296976 libFuzzer: prevent irrelevant strings from leaking into auto-dictionary
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
2018-07-17 16:12:00 +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
Kostya Serebryany 2bd02db943 libFuzzer: always print line-break for NEW_FUNC/PC output
Summary: This is a minor cosmetic change. When function/path exceed ~1000 characters, the output is truncated before the line-break. I noticed this for NEW_FUNC.

Reviewers: kcc

Reviewed By: kcc

Subscribers: llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D48799

llvm-svn: 336461
2018-07-06 19:47:00 +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
Matt Morehouse 988f2da613 [libFuzzer] Use Vector rather than std::vector.
llvm-svn: 335487
2018-06-25 15:59:24 +00:00
Kostya Serebryany 111d0b2aec [libFuzzer] When printing NEW_FUNC, use 1-base indexing.
Summary: Otherwise we print things like [0/1] which is visually confusing.

Reviewers: kcc

Reviewed By: kcc

Subscribers: delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D47837

llvm-svn: 334234
2018-06-07 21:15:24 +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