The CrossOver mutator is meant to cross over two given buffers (referred to as
the first/second buffer henceforth). Previously InsertPartOf/CopyPartOf calls
used in the CrossOver mutator incorrectly inserted/copied part of the second
buffer into a "scratch buffer" (MutateInPlaceHere of the size
CurrentMaxMutationLen), rather than the first buffer. This is not intended
behavior, because the scratch buffer does not always (i) contain the content of
the first buffer, and (ii) have the same size as the first buffer;
CurrentMaxMutationLen is typically a lot larger than the size of the first
buffer. This patch fixes the issue by using the first buffer instead of the
scratch buffer in InsertPartOf/CopyPartOf calls.
A FuzzBench experiment was run to make sure that this change does not
inadvertently degrade the performance. The performance is largely the same; more
details can be found at:
https://storage.googleapis.com/fuzzer-test-suite-public/fixcrossover-report/index.html
This patch also adds two new tests, namely "cross_over_insert" and
"cross_over_copy", which specifically target InsertPartOf and CopyPartOf,
respectively.
- cross_over_insert.test checks if the fuzzer can use InsertPartOf to trigger
the crash.
- cross_over_copy.test checks if the fuzzer can use CopyPartOf to trigger the
crash.
These newly added tests were designed to pass with the current patch, but not
without the it (with 790878f291 these tests do not
pass). To achieve this, -max_len was intentionally given a high value. Without
this patch, InsertPartOf/CopyPartOf will generate larger inputs, possibly with
unpredictable data in it, thereby failing to trigger the crash.
The test pass condition for these new tests is narrowed down by (i) limiting
mutation depth to 1 (i.e., a single CrossOver mutation should be able to trigger
the crash) and (ii) checking whether the mutation sequence of "CrossOver-" leads
to the crash.
Also note that these newly added tests and an existing test (cross_over.test)
all use "-reduce_inputs=0" flags to prevent reducing inputs; it's easier to
force the fuzzer to keep original input string this way than tweaking
cov-instrumented basic blocks in the source code of the fuzzer executable.
Differential Revision: https://reviews.llvm.org/D85554
Two tests `FAIL` on 32-bit sparc:
Profile-sparc :: Posix/instrprof-gcov-parallel.test
UBSan-Standalone-sparc :: TestCases/Float/cast-overflow.cpp
The failure mode is similar:
Undefined first referenced
symbol in file
__atomic_store_4 /var/tmp/instrprof-gcov-parallel-6afe8d.o
__atomic_load_4 /var/tmp/instrprof-gcov-parallel-6afe8d.o
Undefined first referenced
symbol in file
__atomic_load_1 /var/tmp/cast-overflow-72a808.o
This is a known bug: `clang` doesn't inline atomics on 32-bit sparc, unlike
`gcc`.
The patch therefore `XFAIL`s the tests.
Tested on `sparcv9-sun-solaris2.11` and `amd64-pc-solaris2.11`.
Differential Revision: https://reviews.llvm.org/D85346
Currently it is hard to avoid having LLVM link to the system install of
ncurses, since it uses check_library_exists to find e.g. libtinfo and
not find_library or find_package.
With this change the ncurses lib is found with find_library, which also
considers CMAKE_PREFIX_PATH. This solves an issue for the spack package
manager, where we want to use the zlib installed by spack, and spack
provides the CMAKE_PREFIX_PATH for it.
This is a similar change as https://reviews.llvm.org/D79219, which just
landed in master.
Differential revision: https://reviews.llvm.org/D85820
While the instrumentation never calls dfsan_union in fast16labels mode,
the custom wrappers do. We detect fast16labels mode by checking whether
any labels have been created. If not, we must be using fast16labels
mode.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D86012
This sets some config parameters so we can run the asan tests with
llvm-lit,
e.g. `./bin/llvm-lit [...]/compiler-rt/test/asan`
Differential Revision: https://reviews.llvm.org/D83821
Otherwise, lots of these tests fail with a CHECK error similar to:
==12345==AddressSanitizer CHECK failed: compiler-rt/lib/asan/asan_posix.cpp:120 "((0)) == ((pthread_key_create(&tsd_key, destructor)))" (0x0, 0x4e)
This is because the default pthread stubs in FreeBSD's libc always
return failures (such as ENOSYS for pthread_key_create) in case the
pthread library is not linked in.
Reviewed By: arichardson
Differential Revision: https://reviews.llvm.org/D85082
Have the front-end use the `nounwind` attribute on atomic libcalls.
This prevents us from seeing `invoke __atomic_load` in MSAN, which
is problematic as it has no successor for instrumentation to be added.
Unmapping and remapping is dangerous since another thread could touch
the shadow memory while it is unmapped. But there is really no need to
unmap anyway, since mmap(MAP_FIXED) will happily clobber the existing
mapping with zeroes. This is thread-safe since the mmap() is done under
the same kernel lock as page faults are done.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D85947
Add interceptors for `dispatch_async_and_wait[_f]()` which was added in
macOS 10.14. This pair of functions is similar to `dispatch_sync()`,
but does not force a context switch of the queue onto the caller thread
when the queue is active (and hence is more efficient). For TSan, we
can apply the same semantics as for `dispatch_sync()`.
From the header docs:
> Differences with dispatch_sync()
>
> When the runtime has brought up a thread to invoke the asynchronous
> workitems already submitted to the specified queue, that servicing
> thread will also be used to execute synchronous work submitted to the
> queue with dispatch_async_and_wait().
>
> However, if the runtime has not brought up a thread to service the
> specified queue (because it has no workitems enqueued, or only
> synchronous workitems), then dispatch_async_and_wait() will invoke the
> workitem on the calling thread, similar to the behaviour of functions
> in the dispatch_sync family.
Additional context:
> The guidance is to use `dispatch_async_and_wait()` instead of
> `dispatch_sync()` when it is necessary to mix async and sync calls on
> the same queue. `dispatch_async_and_wait()` does not guarantee
> execution on the caller thread which allows to reduce context switches
> when the target queue is active.
> https://gist.github.com/tclementdev/6af616354912b0347cdf6db159c37057
rdar://35757961
Reviewed By: kubamracek
Differential Revision: https://reviews.llvm.org/D85854
base and nptr_label were swapped, which meant we were passing nptr's
shadow as the base to the operation. Usually, the shadow is 0, which
causes strtoull to guess the correct base from the string prefix (e.g.,
0x means base-16 and 0 means base-8), hiding this bug. Adjust the test
case to expose the bug.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D85935
A recent change to sanitizer_common caused us to issue the syscall
madvise(MADV_HUGEPAGE) during HWASAN initialization. This may lead to a
problem if madvise is instrumented (e.g. because libc is instrumented
or the user intercepted it). For example, on Android the syscall may
fail if the kernel does not support transparent hugepages, which leads
to an attempt to set errno in a HWASAN instrumented function. Avoid
this problem by introducing a syscall wrapper and using it to issue
this syscall.
Tested only on Linux; includes untested updates for the other
platforms.
Differential Revision: https://reviews.llvm.org/D85870
Disable huge pages in the TSan shadow regions when no_huge_pages_for_shadow == true (default).
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D85841
Similarly as for pointers, even for integers a == b is usually false.
GCC also uses this heuristic.
Reviewed By: ebrevnov
Differential Revision: https://reviews.llvm.org/D85781
When building on `sparc64-unknown-linux-gnu`, I found that a large number
of `SanitizerCommon-asan-sparc*-Linux` tests were `FAIL`ing, like
SanitizerCommon-asan-sparc-Linux :: Linux/aligned_alloc-alignment.cpp
[...]
SanitizerCommon-asan-sparcv9-Linux :: Linux/aligned_alloc-alignment.cpp
[...]
many of them due to
fatal error: error in backend: Function "_Z14User_OnSIGSEGViP9siginfo_tPv": over-aligned dynamic alloca not supported.
which breaks ASan on Sparc. Currently ASan is only built for the benefit
of `gcc` where it does work. However, when enabling the compilation in
`compiler-rt` to make certain it continues to build, I missed
`compiler-rt/test/sanitizer_common` when disabling ASan testing on Sparc
(it's not yet enabled on Solaris).
This patch fixes the issue.
Tested on `sparcv9-sun-solaris2.11` with the `sanitizer_comon` testsuite enabled.
Differential Revision: https://reviews.llvm.org/D85732
Every now and then SystemZ programs built with ASan crash with
ERROR: AddressSanitizer: stack-overflow on address 0x040000000000
for no apparent reason. The problem is that
BufferedStackTrace::UnwindFast() is specialized for SystemZ: it takes
register 14 from the frame, however, IsValidFrame() is not
specialized, and does not guarantee that frame[14] is going to be a
valid memory access.
Fix by introducing per-arch kFrameSize and using it in IsValidFrame().
Reviewed By: uweigand
Differential Revision: https://reviews.llvm.org/D85822
This fixes https://bugs.llvm.org/show_bug.cgi?id=47118. Before this change, when the sigaction interceptor prevented a signal from being changed, it also prevented the oldact output parameter from being written to. This resulted in a use-of-uninitialized-variable by any program that used sigaction for the purpose of reading signals.
This change fixes this: the regular sigaction implementation is still called, but with the act parameter nullified, preventing any changes.
Patch By: IanPudney
Reviewed By: morehouse
Differential Revision: https://reviews.llvm.org/D85797
Commit 9385aaa848 ("[sancov] Fix PR33732") added zeroext to
__sanitizer_cov_trace(_const)?_cmp[1248] parameters for x86_64 only,
however, it is useful on other targets, in particular, on SystemZ: it
fixes swap-cmp.test.
Therefore, use it on all targets. This is safe: if target ABI does not
require zero extension for a particular parameter, zeroext is simply
ignored. A similar change has been implemeted as part of commit
3bc439bdff ("[MSan] Add instrumentation for SystemZ"), and there were
no problems with it.
Reviewed By: morehouse
Differential Revision: https://reviews.llvm.org/D85689
Rather than handling zlib handling manually, use find_package from CMake
to find zlib properly. Use this to normalize the LLVM_ENABLE_ZLIB,
HAVE_ZLIB, HAVE_ZLIB_H. Furthermore, require zlib if LLVM_ENABLE_ZLIB is
set to YES, which requires the distributor to explicitly select whether
zlib is enabled or not. This simplifies the CMake handling and usage in
the rest of the tooling.
This is a reland of abb0075 with all followup changes and fixes that
should address issues that were reported in PR44780.
Differential Revision: https://reviews.llvm.org/D79219
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
On iOS, when we `longjmp()` out of the signal handler, a subsequent call
to `sigaltstack()` still reports that we are executing on the signal
handler stack.
Tracking rdar://66789814
Differential Revision: https://reviews.llvm.org/D85677
Two tests currently `XPASS` on sparcv9:
Unexpectedly Passed Tests (2):
Builtins-sparcv9-sunos :: compiler_rt_logbl_test.c
Builtins-sparcv9-sunos :: divtc3_test.c
The following patch fixes this.
Tested on `sparcv9-sun-solaris2.11`.
Differential Revision: https://reviews.llvm.org/D85119
Two ubsan tests FAIL on Sparc:
UBSan-Standalone-sparc :: TestCases/TypeCheck/misaligned.cpp
UBSan-Standalone-sparcv9 :: TestCases/TypeCheck/misaligned.cpp
I've reported the details in Bug 47015, but it boils down to the fact that
the `s1` subtest actually incurs a fault on strict-alignment targets like
Sparc which UBSan doesn't expect.
This can be fixed like the `w1` subtest by compiling with
`-fno-sanitize-recover=alignment`.
Tested on `sparcv9-sun-solaris2.11`, `amd64-pc-solaris2.11`, and
`x86_64-pc-linux-gnu`.
Differential Revision: https://reviews.llvm.org/D85433
The former function is particularly optimized for exactly the
use case we're interested in: an all-zero buffer.
This reduces the overhead of calling this function some 80% or
more. This is particularly for instrumenting code heavy with
string processing functions, like grep. An invocation of grep
with the pattern '[aeiou]k[aeiou]' has its runtime reduced by
~75% with this patch
Differential Revision: https://reviews.llvm.org/D84961
Rather than handling zlib handling manually, use find_package from CMake
to find zlib properly. Use this to normalize the LLVM_ENABLE_ZLIB,
HAVE_ZLIB, HAVE_ZLIB_H. Furthermore, require zlib if LLVM_ENABLE_ZLIB is
set to YES, which requires the distributor to explicitly select whether
zlib is enabled or not. This simplifies the CMake handling and usage in
the rest of the tooling.
This is a reland of abb0075 with all followup changes and fixes that
should address issues that were reported in PR44780.
Differential Revision: https://reviews.llvm.org/D79219
As pointed out in D85387, part of the comment for MapDynamicShadow
refactored to sanitizer_common in D83247 was incorrect for non-Linux
versions. Update the comment to reflect that.
Running ninja check-sanitizer fails for after that patch (commit
058f5f6fd8) with the following error:
libRTSanitizerCommon.test.nolibc.x86_64.a(sanitizer_posix.cpp.o): In
function `__sanitizer::GetNamedMappingFd(char const*, unsigned long,
int*)':
..../llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_posix.cpp:358:
undefined reference to `fcntl'
clang-12: error: linker command failed with exit code 1 (use -v to see
invocation)
This patch works around the problem by only calling fcntl if O_CLOEXEC
is not defined.
Reviewed By: plopresti
Differential Revision: https://reviews.llvm.org/D85114
When the FreeBSD qsort() implementation recurses, it does so using an
interposable function call, so we end up calling the interceptor again
and set the saved comparator to wrapped_qsort_compar. This results in an
infinite loop and a eventually a stack overflow since wrapped_qsort_compar
ends up calling itself. This means that ASAN is completely broken on
FreeBSD for programs that call qsort(). I found this while running
check-all on a FreeBSD system a ASAN-instrumented LLVM.
Fix this by checking whether we are recursing inside qsort before writing
to qsort_compar. The same bug exists in the qsort_r interceptor, so use the
same approach there. I did not test the latter since the qsort_r function
signature does not match and therefore it's not intercepted on FreeBSD/macOS.
Fixes https://llvm.org/PR46832
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D84509
Rather than handling zlib handling manually, use find_package from CMake
to find zlib properly. Use this to normalize the LLVM_ENABLE_ZLIB,
HAVE_ZLIB, HAVE_ZLIB_H. Furthermore, require zlib if LLVM_ENABLE_ZLIB is
set to YES, which requires the distributor to explicitly select whether
zlib is enabled or not. This simplifies the CMake handling and usage in
the rest of the tooling.
This is a reland of abb0075 with all followup changes and fixes that
should address issues that were reported in PR44780.
Differential Revision: https://reviews.llvm.org/D79219
This change adds a CMake rule to produce shared object versions of
libFuzzer (no-main). Like the static library versions, these shared
libraries have a copy of libc++ statically linked in. For i386 we don't
link with libc++ since i386 does not support mixing position-
independent and non-position-independent code in the same library.
Patch By: IanPudney
Reviewed By: morehouse
Differential Revision: https://reviews.llvm.org/D84947
This quietly disabled use of zlib on Windows even when building with
-DLLVM_ENABLE_ZLIB=FORCE_ON.
> Rather than handling zlib handling manually, use find_package from CMake
> to find zlib properly. Use this to normalize the LLVM_ENABLE_ZLIB,
> HAVE_ZLIB, HAVE_ZLIB_H. Furthermore, require zlib if LLVM_ENABLE_ZLIB is
> set to YES, which requires the distributor to explicitly select whether
> zlib is enabled or not. This simplifies the CMake handling and usage in
> the rest of the tooling.
>
> This is a reland of abb0075 with all followup changes and fixes that
> should address issues that were reported in PR44780.
>
> Differential Revision: https://reviews.llvm.org/D79219
This reverts commit 10b1b4a231 and follow-ups
64d99cc6ab and
f9fec0447e.
* Add SystemZ to the list of supported architectures.
* XFAIL a few tests.
Coverage reporting is broken, and is not easy to fix (see comment in
coverage.test). Interaction with sanitizers needs to be investigated
more thoroughly, since they appear to reduce coverage in certain cases.
The usage pattern of Bundle variable assumes the machine is little
endian, which is not the case on SystemZ. Fix by converting Bundle to
little-endian when necessary.
These UBSan tests assert the absence of runtime errors via `count 0`,
which means "expect no output". This fails the test unnecessarily in
some environments (e.g., iOS simulator in our case). Alter the test to
be a bit more specific and "expect no error" instead of "expect no
output".
rdar://65503408
Differential Revision: https://reviews.llvm.org/D85155
GlobalISel is the default ISel for aarch64 at -O0. Prior to D78465, GlobalISel
didn't have support for dealing with address-of-global lowerings, so it fell
back to SelectionDAGISel.
HWASan Globals require special handling, as they contain the pointer tag in the
top 16-bits, and are thus outside the code model. We need to generate a `movk`
in the instruction sequence with a G3 relocation to ensure the bits are
relocated properly. This is implemented in SelectionDAGISel, this patch does
the same for GlobalISel.
GlobalISel and SelectionDAGISel differ in their lowering sequence, so there are
differences in the final instruction sequence, explained in
`tagged-globals.ll`. Both of these implementations are correct, but GlobalISel
is slightly larger code size / slightly slower (by a couple of arithmetic
instructions). I don't see this as a problem for now as GlobalISel is only on
by default at `-O0`.
Reviewed By: aemerson, arsenm
Differential Revision: https://reviews.llvm.org/D82615
Dokyung Song