Commit Graph

298 Commits

Author SHA1 Message Date
Max Moroz 74cec618f3 [libFuzzer] Merge: print feature coverage number as well.
Summary:
feature coverage is a useful signal that is available during the merge
process, but was not printed previously.

Output example:

```
$ ./fuzzer -use_value_profile=1 -merge=1 new_corpus/ seed_corpus/
INFO: Seed: 1676551929
INFO: Loaded 1 modules   (2380 inline 8-bit counters): 2380 [0x90d180, 0x90dacc), 
INFO: Loaded 1 PC tables (2380 PCs): 2380 [0x684018,0x68d4d8), 
MERGE-OUTER: 180 files, 78 in the initial corpus
MERGE-OUTER: attempt 1
INFO: Seed: 1676574577
INFO: Loaded 1 modules   (2380 inline 8-bit counters): 2380 [0x90d180, 0x90dacc), 
INFO: Loaded 1 PC tables (2380 PCs): 2380 [0x684018,0x68d4d8), 
INFO: -max_len is not provided; libFuzzer will not generate inputs larger than 1048576 bytes
MERGE-INNER: using the control file '/tmp/libFuzzerTemp.111754.txt'
MERGE-INNER: 180 total files; 0 processed earlier; will process 180 files now
#1	pulse  cov: 134 ft: 330 exec/s: 0 rss: 37Mb
#2	pulse  cov: 142 ft: 462 exec/s: 0 rss: 38Mb
#4	pulse  cov: 152 ft: 651 exec/s: 0 rss: 38Mb
#8	pulse  cov: 152 ft: 943 exec/s: 0 rss: 38Mb
#16	pulse  cov: 520 ft: 2783 exec/s: 0 rss: 39Mb
#32	pulse  cov: 552 ft: 3280 exec/s: 0 rss: 41Mb
#64	pulse  cov: 576 ft: 3641 exec/s: 0 rss: 50Mb
#78	LOADED cov: 602 ft: 3936 exec/s: 0 rss: 88Mb
#128	pulse  cov: 611 ft: 3996 exec/s: 0 rss: 93Mb
#180	DONE   cov: 611 ft: 4016 exec/s: 0 rss: 155Mb
MERGE-OUTER: succesfull in 1 attempt(s)
MERGE-OUTER: the control file has 39741 bytes
MERGE-OUTER: consumed 0Mb (37Mb rss) to parse the control file
MERGE-OUTER: 9 new files with 80 new features added; 9 new coverage edges
```

Reviewers: hctim, morehouse

Reviewed By: morehouse

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

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D66030

llvm-svn: 368617
2019-08-12 20:21:27 +00:00
Max Moroz 3653aeeffa [libFuzzer] Merge: print stats after reading the output corpus dir.
Summary:
The purpose is to be able to extract the number of new edges added to
the original (i.e. output) corpus directory after doing the merge. Use case
example: in ClusterFuzz, we do merge after every fuzzing session, to avoid
uploading too many corpus files, and we also record coverage stats at that
point. Having a separate line indicating stats after reading the initial output
corpus directory would make the stats extraction easier for both humans and
parsing scripts.

Context: https://github.com/google/clusterfuzz/issues/802.

Reviewers: morehouse, hctim

Reviewed By: hctim

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

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D66020

llvm-svn: 368461
2019-08-09 18:20:53 +00:00
Max Moroz df3b465c9c [compiler-rt] Add ConsumeProbability and ConsumeFloatingPoint methods to FDP.
Summary:
Also slightly cleaned up the comments and changed the header's extension
back to `.h` as per comments on https://reviews.llvm.org/D65812.

New methods added:

* `ConsumeProbability` returns [0.0, 1.0] by consuming an unsigned integer value
   from the input data and dividing that value by the integer's max value.
* `ConsumeFloatingPointInRange` returns a floating point value in the given
   range. Relies on `ConsumeProbability` method. This method does not have the
   limitation of `std::uniform_real_distribution` that requires the given range
   to be <= the floating point type's max. If the range is too large, this
   implementation will additionally call `ConsumeBool` to decide whether the
   result will be in the first or the second half of the range.
* `ConsumeFloatingPoint` returns a floating point value in the range
  `[std::numeric_limits<T>::lowest(), std::numeric_limits<T>::min()]`.

Tested on Linux, Mac, Windows.


Reviewers: morehouse

Reviewed By: morehouse

Subscribers: kubamracek, mgorny, dberris, delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D65905

llvm-svn: 368331
2019-08-08 19:49:37 +00:00
Max Moroz 6c619aadc4 [compiler-rt] Rename FuzzedDataProvider.h to .hpp and other minor changes.
Summary:
.hpp makes more sense for this header as it's C++ only, plus it
contains the actual implementation.

Reviewers: Dor1s

Reviewed By: Dor1s

Subscribers: kubamracek, dberris, mgorny, delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D65812

llvm-svn: 368054
2019-08-06 16:02:39 +00:00
Yi Kong 295d4b7727 Build libfuzzer libcxx-static with PIC
r356153 changed default build option of static libcxx to no PIC. We now
need to explicitly specify CMAKE_POSITION_INDEPENDENT_CODE to get PIC
libcxx.

Differential Revision: https://reviews.llvm.org/D65773

llvm-svn: 367943
2019-08-05 22:55:17 +00:00
Max Moroz f1b0a93e3a [compiler-rt] Move FDP to include/fuzzer/FuzzedDataProvider.h for easier use.
Summary:
FuzzedDataProvider is a helper class for writing fuzz targets that fuzz
multple inputs simultaneously. The header is supposed to be used for fuzzing
engine agnostic fuzz targets (i.e. the same target can be used with libFuzzer,
AFL, honggfuzz, and other engines). The common thing though is that fuzz targets
are typically compiled with clang, as it provides all sanitizers as well as
different coverage instrumentation modes. Therefore, making this FDP class a
part of the compiler-rt installation package would make it easier to develop
and distribute fuzz targets across different projects, build systems, etc.
Some context also available in https://github.com/google/oss-fuzz/pull/2547.

This CL does not delete the header from `lib/fuzzer/utils` directory in order to
provide the downstream users some time for a smooth migration to the new
header location.

Reviewers: kcc, morehouse

Reviewed By: morehouse

Subscribers: lebedev.ri, kubamracek, dberris, mgorny, delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D65661

llvm-svn: 367917
2019-08-05 19:55:52 +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
Max Moroz 374398afb7 [libFuzzer] Fix __sanitizer_print_memory_profile return type in ExtFunctions.def
Summary:
Looks like a typo, as that function actually returns void and is used
as such in libFuzzer code as well.

Reviewers: kcc, Dor1s

Reviewed By: Dor1s

Subscribers: delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D65160

llvm-svn: 366834
2019-07-23 18:26:53 +00:00
Max Moroz 2d73994046 [libFuzzer] Include FuzzedDataProvider.h in the test without "utils" subdir.
Summary:
This way the test would better match the intended usage of the header,
plus it makes some additional testing (e.g. in CI) a bit easier to set up.

Reviewers: morehouse

Reviewed By: morehouse

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

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D64440

llvm-svn: 365544
2019-07-09 19:28:14 +00:00
Petr Hosek d9a59aeb04 [libFuzzer] Migrate to the new exception syscalls on Fuchsia
This is part of the transition to the new Fuchsia exception syscalls
signature.

Differential Revision: https://reviews.llvm.org/D63897

llvm-svn: 364594
2019-06-27 21:13:06 +00:00
Kostya Serebryany 679669a77e [libFuzzer] split DataFlow.cpp into two .cpp files, one of which can be compiled w/o dfsan to speed things up (~25% speedup)
llvm-svn: 364002
2019-06-21 01:39:35 +00:00
Kostya Serebryany 27cf743bff [libFuzzer] ensure that DFT and autofocus works for C++ (mangled) functions
llvm-svn: 363905
2019-06-20 01:48:45 +00:00
Max Moroz 46972b065c [libFuzzer] Remove too aggressive static_assert in FuzzedDataProvider.
Summary:
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-full/builds/31

error: static_assert failed due to requirement
'std::numeric_limits<char>::is_signed' "Destination type must be
signed."
    static_assert(std::numeric_limits<TS>::is_signed,
    ^             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/buildslave/buildslave/clang-cmake-aarch64-full/llvm/projects/compiler-rt/lib/fuzzer/utils/FuzzedDataProvider.h:126:19:
note: in instantiation of function template specialization
'FuzzedDataProvider::ConvertUnsignedToSigned<char, unsigned char>'
requested here
      char next = ConvertUnsignedToSigned<char>(data_ptr_[0]);
                  ^
1 error generated.

Reviewers: Dor1s

Reviewed By: Dor1s

Subscribers: javed.absar, kristof.beyls, delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D63553

llvm-svn: 363805
2019-06-19 14:14:27 +00:00
Max Moroz a0eb49c26e [libFuzzer] Improve FuzzedDataProvider helper.
Summary:
The following changes are made based on the feedback from Tim King:
- Removed default template parameters, to have less assumptions.
- Implemented `ConsumeBytesWithTerminator` method.
- Made `PickValueInArray` method work with `initializer_list` argument.
- Got rid of `data_type` type alias, that was redundant.
- Refactored `ConsumeBytes` logic into a private method for better code reuse.
- Replaced implementation defined unsigned to signed conversion.
- Fixed `ConsumeRandomLengthString` to always call `shrink_to_fit`.
- Clarified and fixed some commments.
- Applied clang-format to both the library and the unittest source.

Tested on Linux, Mac, Windows.

Reviewers: morehouse, metzman

Reviewed By: morehouse

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

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D63348

llvm-svn: 363735
2019-06-18 20:29:11 +00:00
Kostya Serebryany 0feed5d585 [libFuzzer] in autofocus mode, give more weight to functions with DFT
llvm-svn: 363473
2019-06-14 23:29:56 +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 2fa6838e5f [libFuzzer] fix -Werror build
llvm-svn: 363469
2019-06-14 22:34:30 +00:00
Kostya Serebryany 3f39123d15 [libFuzzer] simplify the DFT trace collection using the new faster DFSan mode that traces up to 16 labels at a time and never runs out of labels. Second attempt. This time with a fix for windows (putenv instead of setenv))
llvm-svn: 363445
2019-06-14 19:54:32 +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
Hans Wennborg 9bc707c0e5 Revert r363326 "[libFuzzer] simplify the DFT trace collection using the new faster DFSan mode that traces up to 16 labels at a time and never runs out of labels."
It broke the Windows build:

C:\b\s\w\ir\cache\builder\src\third_party\llvm\compiler-rt\lib\fuzzer\FuzzerDataFlowTrace.cpp(243): error C3861: 'setenv': identifier not found

This also reverts the follow-up r363327.

llvm-svn: 363358
2019-06-14 07:32:22 +00:00
Kostya Serebryany 2fa83cb7ee [libFuzzer] simplify the DFT trace collection using the new faster DFSan mode that traces up to 16 labels at a time and never runs out of labels.
llvm-svn: 363326
2019-06-13 21:17:49 +00:00
Max Moroz 10ed68189a Add FuzzedDataProvider helper class / single header library.
Summary:
This class is useful for writing fuzz target that have multiple inputs.

Current CL imports the existing `FuzzedDataProvider` from Chromium
without any modifications. Feel free to review it thoroughly, if you're
interested, but I'd prefer changing the class in a follow up CL.

The CL also introduces an exhaustive test for the library, as the behavior
of `FuzzedDataProvider` must not change over time.

In follow up CLs I'm planning on changing some implementation details
(I can share a doc with some comments to be addressed). After that, we
will document how `FuzzedDataProvider` should be used.

I have tested this on Linux, Windows and Mac platforms.

Reviewers: morehouse, metzman, kcc

Reviewed By: morehouse

Subscribers: metzman, thakis, rnk, mgorny, ormris, delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D62733

llvm-svn: 363071
2019-06-11 14:30:18 +00:00
Kostya Serebryany 060f4b48d5 [libFuzzer] when using data-flow-trace (DFT) only load the DFT for the files present in the corpus
llvm-svn: 361579
2019-05-24 00:43:52 +00:00
Kostya Serebryany eac9a7830b [libFuzzer] remove the data-flow-trace (DFT) python scripts; their functionality is now part of libFuzzer proper; also write functions.txt to the disk only if this file doesn't exist yet
llvm-svn: 361452
2019-05-23 01:03:42 +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
Petr Hosek 9bd4dc929c [libFuzzer] Ignore synthetic exceptions on Fuchsia
Fuchsia has several exceptions which are merely informational and should
not be treated as crashes. This patch puts logic that read from the
exception port and handled the exception in a loop, and ignores
non-exceptions and informational exceptions.

Patch By: aarongreen

Differential Revision: https://reviews.llvm.org/D62226

llvm-svn: 361407
2019-05-22 16:36:35 +00:00
Kostya Serebryany 2e2dfe2186 [libFuzzer] replace string_view with string to fix the bots. This is NFC, just slower.
llvm-svn: 360717
2019-05-14 22:16:04 +00:00
Kostya Serebryany 1e8104daf2 [libFuzzer] #include <string_view>, hopefully should fix the windows build
llvm-svn: 360715
2019-05-14 22:05:41 +00:00
Kostya Serebryany 27d22b6b7a [libFuzzer] reimplement DFT's collect_data_flow inside libFuzzer so that we don't need external python scripts
llvm-svn: 360712
2019-05-14 21:47:35 +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
Matt Morehouse 3478494c1f [libFuzzer] Unpoison parameters before calling user callback.
Summary:
Fixes an MSan false positive when compiling with
-fsanitize=memory,fuzzer.

See https://github.com/google/oss-fuzz/issues/2369 for more details.

Reviewers: kcc

Reviewed By: kcc

Subscribers: llvm-commits, metzman, eugenis

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61753

llvm-svn: 360390
2019-05-09 22:48:46 +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 e9aaa5582f [libFuzzer] implement -focus_function=auto, to be used with Data Flow Traces
llvm-svn: 360378
2019-05-09 21:29:45 +00:00
Kostya Serebryany e13eff293d [libFuzzer] DFT: when dumping coverage, also dump the total number of instrumented blocks in a function; update merge_data_flow.py to merge coverage
llvm-svn: 360272
2019-05-08 17:20:09 +00:00
Kostya Serebryany 219b2b3a4a [libFuzzer] extend the data flow tracer to also produce basic block coverage for every input. An extended test coming in a separte change.
llvm-svn: 360213
2019-05-08 00:51:15 +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
Jonathan Metzman d61084901c change order
llvm-svn: 359587
2019-04-30 17:58:57 +00:00
Jonathan Metzman 2697664582 [libFuzzer] Enable for i386
Summary: Get libFuzzer to build on i386 and fix tests.

Subscribers: mgorny, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D61070

llvm-svn: 359585
2019-04-30 17:58:56 +00:00
Jonathan Metzman f721230831 Enable x86 builds
llvm-svn: 359583
2019-04-30 17:58:54 +00:00
Matt Morehouse 1b76063a5e [libFuzzer] Disable MSan interceptors in SIGINT handler.
Summary:
Avoids an MSan false positive if the SIGINT comes while the user
callback is running.  The false positive happens when the interrupt
handler calls opendir() to remove some temporary files, which is
intercepted by MSan.

Fixes https://github.com/google/oss-fuzz/issues/2332.

Reviewers: kcc

Reviewed By: kcc

Subscribers: llvm-commits, Dor1s, metzman

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61163

llvm-svn: 359254
2019-04-26 00:17:41 +00:00
Chris Bieneman 2436237895 [CMake] Add fuzzer as a component for runtime builds
Calling `add_compiler_rt_component` sets up the component connection between runtime builds and the parent CMake configuration. Adding this call allows specifying `fuzzer` as a `LLVM_RUNTIME_DISTRIBUTION_COMPONENT`.

llvm-svn: 358780
2019-04-19 20:13:25 +00:00
Kostya Serebryany 14ada6d1ad [libFuzzer] revert part of r358726 committed by mistake (oops)
llvm-svn: 358727
2019-04-19 01:40:16 +00:00
Kostya Serebryany bbb8522bde [libFuzzer] in fork mode, make sure the child stats are always collected. This should fix the flakiness in fork-ubsan.test
llvm-svn: 358726
2019-04-19 01:39:14 +00:00
Jonathan Metzman 139e216e66 Summary:
Add close_fd_mask functionality to AFL driver.

Summary:
Add support for env var AFL_DRIVER_CLOSE_FD_MASK which behaves
the same as libFuzzer's -close_fd_mask=1.

Also add tests.

Reviewers: kcc, vitalybuka, morehouse

Reviewed By: morehouse

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D60334

llvm-svn: 358703
2019-04-18 18:49:11 +00:00
Matt Morehouse 57213d839a [libFuzzer] Remove tautological compare.
llvm-svn: 358510
2019-04-16 17:38:19 +00:00
Kostya Serebryany 5e67abd91f [libFuzzer] speedup the merge step in the fork mode by merging only the files that have unique features.
llvm-svn: 358320
2019-04-13 01:57:33 +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
Max Moroz b6e6d3c740 [libFuzzer] Fix DataFlow.cpp logic when tracing long inputs.
Summary:
1. Do not create DFSan labels for the bytes which we do not trace. This is where we run out of labels at the first place.
2. When dumping the traces on the disk, make sure to offset the label identifiers by the number of the first byte in the trace range.
3. For the last label, make sure to write it at the last position of the trace bit string, as that label represents the input size, not any particular byte.

Also fixed the bug with division in python which I've introduced when migrated the scripts to Python3 (`//` is required for integral division).

Otherwise, the scripts are wasting too much time unsuccessfully trying to
collect and process traces from the long inputs. For more context, see
https://github.com/google/oss-fuzz/issues/1632#issuecomment-481761789

Reviewers: kcc

Reviewed By: kcc

Subscribers: delcypher, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D60538

llvm-svn: 358311
2019-04-12 21:00:12 +00:00
Kostya Serebryany 65132e2118 [libFuzzer] support -runs=N in the fork mode. Make sure we see one-line reports from ubsan in the fork mode. Test both
llvm-svn: 358306
2019-04-12 20:20:57 +00:00