The ExecuteCommand function in fuchsia used to prefix the
getOutputFile for each command run with the artifact_prefix flag if
it was available, because fuchsia components don't have a writable working
directory. However, if a file with a global path is provided, fuchsia
should honor that.
An example of this is using the global /tmp directory to store stuff.
In fuchsia it ended up being translated to data///tmp, whereas we want
to make sure it is using /tmp (which is available to components using the
isolated-temp feature).
To test this I made the change, compiled fuchsia with this toolchain and
ran a fuzzer with the -fork=1 flag (that mode makes use of the /tmp
directory). I also tested that normal fuzzing workflow was not affected
by this.
Author: charco (Marco Vanotti)
Differential Revision: https://reviews.llvm.org/D68774
llvm-svn: 374612
Fuchsia doesn't have /proc/id/maps, so it relies on the kernel logging system
to provide the DSO map to be able to symbolize in the context of ASLR. The DSO
map is logged automatically on Fuchsia when encountering a crash or writing to
the sanitizer log for the first time in a process. There are several cases
where libFuzzer doesn't encounter a crash, e.g. on timeouts, OOMs, and when
configured to print new PCs as they become covered, to name a few. Therefore,
this change always writes to the sanitizer log on startup to ensure the DSO map
is available in the log.
Author: aarongreen
Differential Revision: https://reviews.llvm.org/D66233
llvm-svn: 372056
Summary:
This change allows to perform corpus merging in two steps. This is useful when
the user wants to address the following two points simultaneously:
1) Get trustworthy incremental stats for the coverage and corpus size changes
when adding new corpus units.
2) Make sure the shorter units will be preferred when two or more units give the
same unique signal (equivalent to the `REDUCE` logic).
This solution was brainstormed together with @kcc, hopefully it looks good to
the other people too. The proposed use case scenario:
1) We have a `fuzz_target` binary and `existing_corpus` directory.
2) We do fuzzing and write new units into the `new_corpus` directory.
3) We want to merge the new corpus into the existing corpus and satisfy the
points mentioned above.
4) We create an empty directory `merged_corpus` and run the first merge step:
`
./fuzz_target -merge=1 -merge_control_file=MCF ./merged_corpus ./existing_corpus
`
this provides the initial stats for `existing_corpus`, e.g. from the output:
`
MERGE-OUTER: 3 new files with 11 new features added; 11 new coverage edges
`
5) We recreate `merged_corpus` directory and run the second merge step:
`
./fuzz_target -merge=1 -merge_control_file=MCF ./merged_corpus ./existing_corpus ./new_corpus
`
this provides the final stats for the merged corpus, e.g. from the output:
`
MERGE-OUTER: 6 new files with 14 new features added; 14 new coverage edges
`
Alternative solutions to this approach are:
A) Store precise coverage information for every unit (not only unique signal).
B) Execute the same two steps without reusing the control file.
Either of these would be suboptimal as it would impose an extra disk or CPU load
respectively, which is bad given the quadratic complexity in the worst case.
Tested on Linux, Mac, Windows.
Reviewers: morehouse, metzman, hctim, kcc
Reviewed By: morehouse
Subscribers: JDevlieghere, delcypher, mgrang, #sanitizers, llvm-commits, kcc
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D66107
llvm-svn: 371620
Renames GTEST_NO_LLVM_RAW_OSTREAM -> GTEST_NO_LLVM_SUPPORT and guards
the new features behind it.
This reverts commit a063bcf3ef5a879adbe9639a3c187d876eee0e66.
llvm-svn: 369527
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
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
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
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
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
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
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
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
This is part of the transition to the new Fuchsia exception syscalls
signature.
Differential Revision: https://reviews.llvm.org/D63897
llvm-svn: 364594
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
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
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
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
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
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
