Summary:
Disables certain CMP optimizations to improve fuzzing signal under -O1
and -O2.
Switches all fuzzer tests to -O2 except for a few leak tests where the
leak is optimized out under -O2.
Reviewers: kcc, vitalybuka
Reviewed By: vitalybuka
Subscribers: cfe-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D44798
llvm-svn: 328384
Summary:
Following-up the refactoring of mmap interceptors, adding a new common
option to detect PROT_WRITE|PROT_EXEC pages request.
Patch by David CARLIER
Reviewers: vitalybuka, vsk
Reviewed By: vitalybuka
Subscribers: krytarowski, #sanitizers
Differential Revision: https://reviews.llvm.org/D44194
llvm-svn: 328151
New API passes a callback function to the external symbolizer,
allowing it to add multiple frames to the traceback. Note that
the old interface API will be still supported until the clients
migrate to the new one.
Author: asmundak (Alexander Smundak)
Reviewed in: https://reviews.llvm.org/D44714
llvm-svn: 328079
Summary:
vfork is not ASan-friendly because it modifies stack shadow in the
parent process address space. While it is possible to compensate for that with, for example,
__asan_handle_no_return before each call to _exit or execve and friends, simply replacing
vfork with fork looks like by far the easiest solution.
Posix compliant programs can not detect the difference between vfork and fork.
Fixes https://github.com/google/sanitizers/issues/925
Reviewers: kcc, vitalybuka
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D44587
llvm-svn: 327752
Summary: Following-up the refactoring of mmap interceptors, adding a new common option to detect PROT_WRITE|PROT_EXEC pages request.
Patch by David CARLIER
Reviewers: vitalybuka, vsk
Reviewed By: vitalybuka
Subscribers: krytarowski, #sanitizers
Differential Revision: https://reviews.llvm.org/D44194
llvm-svn: 327747
Summary: Following-up the refactoring of mmap interceptors, adding a new common option to detect PROT_WRITE|PROT_EXEC pages request.
Patch by David CARLIER
Reviewers: vitalybuka, vsk
Reviewed By: vitalybuka
Subscribers: krytarowski, #sanitizers
Differential Revision: https://reviews.llvm.org/D44194
llvm-svn: 327696
by explicitly listing where we expect this test to work.
Because this test invokes undefined behaviour all sorts of things
can happen (e.g. crash, or on some bots asan manages to catch
something). The test seems to pass okay on Darwin (x86_64/x86_64/i386)
and on Linux (x86_64/i386) so explicitly require one of these platforms
to run the test.
llvm-svn: 327185
The retpoline mitigation for variant 2 of CVE-2017-5715 inhibits the
branch predictor, and as a result it can lead to a measurable loss of
performance. We can reduce the performance impact of retpolined virtual
calls by replacing them with a special construct known as a branch
funnel, which is an instruction sequence that implements virtual calls
to a set of known targets using a binary tree of direct branches. This
allows the processor to speculately execute valid implementations of the
virtual function without allowing for speculative execution of of calls
to arbitrary addresses.
This patch extends the whole-program devirtualization pass to replace
certain virtual calls with calls to branch funnels, which are
represented using a new llvm.icall.jumptable intrinsic. It also extends
the LowerTypeTests pass to recognize the new intrinsic, generate code
for the branch funnels (x86_64 only for now) and lay out virtual tables
as required for each branch funnel.
The implementation supports full LTO as well as ThinLTO, and extends the
ThinLTO summary format used for whole-program devirtualization to
support branch funnels.
For more details see RFC:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120672.html
Differential Revision: https://reviews.llvm.org/D42453
llvm-svn: 327163
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection. See the included testcase for an example.
Differential Revision: https://reviews.llvm.org/D43959
llvm-svn: 327062
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.
Differential Revision: https://reviews.llvm.org/D43959
llvm-svn: 327031
This changes the add_custom_libcxx macro to resemble the
llvm_ExternalProject_Add. The primary motivation is to avoid
unnecessary libFuzzer rebuilds that are being done on every
Ninja/Make invocation. The libc++ should be only rebuilt whenever
the libc++ source itself changes.
Differential Revision: https://reviews.llvm.org/D43213
llvm-svn: 326921
Summary:
A few changes related to logging:
- prepend `Scudo` to the error messages so that users can identify that we
reported an error;
- replace a couple of `Report` calls in the RSS check code with
`dieWithMessage`/`Print`, mark a condition as `UNLIKELY` in the process;
- change some messages so that they all look more or less the same. This
includes the `CHECK` message;
- adapt a couple of tests with the new strings.
A couple of side notes: this results in a few 1-line-blocks, for which I left
brackets. There doesn't seem to be any style guide for that, I can remove them
if need be. I didn't use `SanitizerToolName` in the strings, but directly
`Scudo` because we are the only users, I could change that too.
Reviewers: alekseyshl, flowerhack
Reviewed By: alekseyshl
Subscribers: mgorny, delcypher, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D44171
llvm-svn: 326901
Darwin needs xlocale.h but I see no precedence in the code how non-Posix
headers like this are handled and I am not experienced with this code. Just
disable the tests for now to recover the bots.
rdar://38208146
llvm-svn: 326874
Summary:
This change adds APIs to allow logging implementations to provide a
function for iterating through in-memory buffers (if they hold in-memory
buffers) and a way for users to generically deal with these buffers
in-process. These APIs are:
- __xray_log_set_buffer_iterator(...) and
__xray_log_remove_buffer_iterator(): installs and removes an
iterator function that takes an XRayBuffer and yields the next one.
- __xray_log_process_buffers(...): takes a function pointer that can
take a mode identifier (string) and an XRayBuffer to process this
data as they see fit.
The intent is to have the FDR mode implementation's buffers be
available through this `__xray_log_process_buffers(...)` API, so that
they can be streamed from memory instead of flushed to disk (useful for
getting the data to a network, or doing in-process analysis).
Basic mode logging will not support this mechanism as it's designed to
write the data mostly to disk.
Future implementations will may depend on this API as well, to allow for
programmatically working through the XRay buffers exposed to the
users in some fashion.
Reviewers: eizan, kpw, pelikan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43495
llvm-svn: 326866
Summary:
Enabling the memory sanitizer support for FreeBSD, most of unit tests are compatible.
- Adding fstat and stressor_r interceptors.
- Updating the struct link_map access since most likely the struct Obj_Entry had been updated since.
- Disabling few unit tests until further work is needed (or we can assume it can work in real world code).
Patch by: David CARLIER
Reviewers: vitalybuka, krytarowski
Reviewed By: vitalybuka
Subscribers: eugenis, dim, srhines, emaste, kubamracek, mgorny, fedor.sergeev, hintonda, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D43080
llvm-svn: 326644
Programs without any code in them should export the exact same set of
symbols as programs with code, at least on Darwin. This is done to make
text-based API verification possible for certain Darwin frameworks.
llvm-svn: 326351
Update min deployment target in some tests so that they don't try
to link against libarclite and don't fail when it's not available.
rdar://problem/29253617
Reviewers: vsk, kubamracek
Reviewed By: vsk
Subscribers: jkorous-apple, cfe-commits
Differential Revision: https://reviews.llvm.org/D43787
llvm-svn: 326143
Summary:
Fixes Bug 32434
See https://bugs.llvm.org/show_bug.cgi?id=32434
Short summary:
std::rethrow_exception does not use __cxa_throw to rethrow the exception, so if
it is called from uninstrumented code, it will leave the stack poisoned. This
can lead to false positives.
Long description:
For functions which don't return normally (e.g. via exceptions), asan needs to
unpoison the entire stack. It is not known before a call to such a function
where execution will continue, some function which don't contain cleanup code
like destructors might be skipped. After stack unwinding, execution might
continue in uninstrumented code.
If the stack has been poisoned before such a function is called, but the stack
is unwound during the unconventional return, then zombie redzones (entries) for
no longer existing stack variables can remain in the shadow memory. Normally,
this is avoided by asan generating a call to asan_handle_no_return before all
functions marked as [[noreturn]]. This asan_handle_no_return unpoisons the
entire stack. Since these [[noreturn]] functions can be called from
uninstrumented code, asan also introduces interceptor functions which call
asan_handle_no_return before running the original [[noreturn]] function;
for example, cxa_throw is intercepted.
If a [[noreturn]] function is called from uninstrumented code (so the stack is
left poisoned) and additionally, execution continues in uninstrumented code, new
stack variables might be introduced and overlap with the stack variables
which have been removed during stack unwinding. Since the redzones are not
cleared nor overwritten by uninstrumented code, they remain but now contain
invalid data.
Now, if the redzones are checked against the new stack variables, false
positive reports can occur. This can happen for example by the uninstrumented
code calling an intercepted function such as memcpy, or an instrumented
function.
Intercepting std::rethrow_exception directly is not easily possible since it
depends on the C++ standard library implementation (e.g. libcxx vs libstdc++)
and the mangled name it produces for this function. As a rather simple
workaround, we're intercepting _Unwind_RaiseException for libstdc++. For
libcxxabi, we can intercept the ABI function __cxa_rethrow_primary_exception.
Patch by Robert Schneider.
Reviewers: kcc, eugenis, alekseyshl, vitalybuka
Reviewed By: vitalybuka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42644
llvm-svn: 326132
Summary:
Print current stack on CHECK violation to aid debugging and
match other sanitizers functionality.
Reviewers: eugenis
Subscribers: delcypher, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D43692
llvm-svn: 326105
Summary:
Start making the Scudo tests less Linux-y:
- `malloc_usable_size` doesn't exist everywhere, so replace them with
`__sanitizer_get_allocated_size` which we provide;
- move all the `memalign` related tests into `memalign.c` since it's also not
available everywhere.
I also noticed that the `memalign.c` was missing a line in one of the loops.
Reviewers: alekseyshl
Reviewed By: alekseyshl
Subscribers: delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D43393
llvm-svn: 326100
Summary:
The setlocale(3) function reloads the ctype(3) arrays from
external files. This happens behind the scenes in the internals
of libc (citrus library, runes functions etc).
ctype(3) functions like isspace(3) can be provided with two
variations on NetBSD: inlined or via a global symbol in libc:
```
#if defined(_NETBSD_SOURCE) && !defined(_CTYPE_NOINLINE) && \
!defined(__cplusplus)
#include <sys/ctype_inline.h>
#else
#include <sys/ctype_bits.h>
#endif
```
The in-lined versions are de-facto array lookup operations.
```
#define isspace(c) ((int)((_ctype_tab_ + 1)[(c)] & _CTYPE_S))
```
After setting setlocale(3) the ctype(3) arrays (_ctype_tab_,
_toupper_tab_, _tolower_tab_) are reload behind the scenes
and they are required to be marked as initialized.
Set them initialized inside the common setlocale(3) interceptor.
The arrays are of size of 257 elements: 0..255 + 1 (EOF).
This corrects errors on NetBSD/amd64 in applications
prebuilt with MSan.
Sponsored by <The NetBSD Foundation>
Reviewers: vitalybuka, dvyukov, joerg
Reviewed By: vitalybuka
Subscribers: llvm-commits, kubamracek, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D42020
llvm-svn: 326008
Reported on a buildbot:
Error in XFAIL list:
couldn't parse text: '| arm || aarch64 || mips'
in expression: 'freebsd | arm || aarch64 || mips'
Add || in the place of |
Fallout from D43382
llvm-svn: 325751
Vitaly Buka