Commit Graph

24 Commits

Author SHA1 Message Date
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
Joe Pletcher f897e82bfd [fuzzer] Add Windows Visual C++ exception intercept
Adds a new option, `handle_winexcept` to try to intercept uncaught
Visual C++ exceptions on Windows. On Linux, such exceptions are handled
implicitly by `std::terminate()` raising `SIBABRT`. This option brings the
Windows behavior in line with Linux.

Unfortunately this exception code is intentionally undocumented, however
has remained stable for the last decade. More information can be found
here: https://devblogs.microsoft.com/oldnewthing/20100730-00/?p=13273

Reviewed By: morehouse, metzman

Differential Revision: https://reviews.llvm.org/D89755
2020-11-12 13:11:14 -08:00
Ilya Leoshkevich 9df7ee34e1 [libFuzzer] Fix minimizing timeouts
When one tries to minimize timeouts using -minimize_crash=1,
minimization immediately fails. The following sequence of events is
responsible for this:

[parent] SIGALRM occurs
[parent] read() returns -EINTR (or -ERESTARTSYS according to strace)
[parent] fgets() returns NULL
[parent] ExecuteCommand() closes child's stdout and returns
[child ] SIGALRM occurs
[child ] AlarmCallback() attempts to write "ALARM: ..." to stdout
[child ] Dies with SIGPIPE without calling DumpCurrentUnit()
[parent] Does not see -exact_artifact_path and exits

When minimizing, the timer in parent is not necessary, so fix by not
setting it in this case.

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D85359
2020-08-11 22:16:12 +02:00
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
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 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
Marco Vanotti e5b603a4c3 [libFuzzer] don't use /dev/null for DiscardOuput in Fuchsia.
Summary:

This commit moves the `DiscardOutput` function in FuzzerIO to
FuzzerUtil, so fuchsia can have its own specialized version.

In fuchsia, accessing `/dev/null` is not supported, and there's nothing
similar to a file that discards everything that is written to it. The
way of doing something similar in fuchsia is by using `fdio_null_create`
and binding that to a file descriptor with `fdio_bind_to_fd`.

This change should fix one of the issues with the `-close_fd_mask` flag
in libfuzzer, in which closing stdout was not working due to
`fopen("/dev/null", "w")` returning `NULL`.

Reviewers: kcc, aarongreen

Subscribers: #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D69593
2019-11-21 16:56:05 -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
Jonathan Metzman 7821f892bf [libFuzzer] Remove extra semicolons
Summary:
Remove extra semicolons so that libFuzzer can compile with
-Werror -Wextra-semi

Reviewers: Dor1s, morehouse, thakis

Reviewed By: Dor1s, morehouse

Subscribers: jdoerfert, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D58674

llvm-svn: 354902
2019-02-26 17:46:13 +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
Martin Storsjo e199a2d434 [libFuzzer] [Windows] Include windows.h and psapi.h with lowercase
This fixes building on a case sensitive filesystem with mingw-w64
headers, where all headers are lowercase, and matches how these
headers are included elsewhere in compiler-rt.

Also include these headers with angle brackets, as they are system
headers.

Differential Revision: https://reviews.llvm.org/D51913

llvm-svn: 341983
2018-09-11 19:11:54 +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
Matt Morehouse 04304d129b [libFuzzer] Encapsulate commands in a class.
Summary:
To be more portable (especially w.r.t. platforms without system()),
commands should be managed programmatically rather than via string
manipulation on the command line. This change introduces
Fuzzer::Command, with methods to manage arguments and flags, set output
options, and execute the command.

Patch By: aarongreen

Reviewers: kcc, morehouse

Reviewed By: kcc, morehouse

Subscribers: llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D40103

llvm-svn: 319680
2017-12-04 19:25:59 +00:00
Kostya Serebryany 25d6b95679 [libFuzzer] remove a couple of reduntant includes
llvm-svn: 312848
2017-09-09 00:56:34 +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