On linux, some architectures had an ABI transition from 64-bit long double
(ie. same as double) to 128-bit long double. On those, glibc symbols
involving long doubles come in two versions, and we need to pass the
correct one to dlvsym when intercepting them.
A few more functions we intercept are also versioned (all printf, scanf,
strtold variants), but there's no need to fix these, as the REAL() versions
are never called.
Differential Revision: http://reviews.llvm.org/D19555
llvm-svn: 267794
Current interface assumes that Go calls ProcWire/ProcUnwire
to establish the association between thread and proc.
With the wisdom of hindsight, this interface does not work
very well. I had to sprinkle Go scheduler with wire/unwire
calls, and any mistake leads to hard to debug crashes.
This is not something one wants to maintian.
Fortunately, there is a simpler solution. We can ask Go
runtime as to what is the current Processor, and that
question is very easy to answer on Go side.
Switch to such interface.
llvm-svn: 267703
This is reincarnation of http://reviews.llvm.org/D17648 with the bug fix pointed out by Adhemerval (zatrazz).
Currently ThreadState holds both logical state (required for race-detection algorithm, user-visible)
and physical state (various caches, most notably malloc cache). Move physical state in a new
Process entity. Besides just being the right thing from abstraction point of view, this solves several
problems:
Cache everything on P level in Go. Currently we cache on a mix of goroutine and OS thread levels.
This unnecessary increases memory consumption.
Properly handle free operations in Go. Frees are issue by GC which don't have goroutine context.
As the result we could not do anything more than just clearing shadow. For example, we leaked
sync objects and heap block descriptors.
This will allow to get rid of libc malloc in Go (now we have Processor context for internal allocator cache).
This in turn will allow to get rid of dependency on libc entirely.
Potentially we can make Processor per-CPU in C++ mode instead of per-thread, which will
reduce resource consumption.
The distinction between Thread and Processor is currently used only by Go, C++ creates Processor per OS thread,
which is equivalent to the current scheme.
llvm-svn: 267678
We've reset thr->ignore_reads_and_writes, but forget to do
thr->fast_state.ClearIgnoreBit(). So ignores were not effective
reset and fast_state.ignore_bit was corrupted if signal handler
itself uses ignores.
Properly reset/restore fast_state.ignore_bit around signal handlers.
llvm-svn: 265288
Summary:
Currently, sanitizer_common_interceptors.inc has an implicit, undocumented
assumption that the sanitizer including it has previously declared
interceptors for memset and memmove. Since the memset, memmove, and memcpy
routines require interception by many sanitizers, we add them to the
set of common interceptions, both to address the undocumented assumption
and to speed future tool development. They are intercepted under a new
flag intercept_intrin.
The tsan interceptors are removed in favor of the new common versions. The
asan and msan interceptors for these are more complex (they incur extra
interception steps and their function bodies are exposed to the compiler)
so they opt out of the common versions and keep their own.
Reviewers: vitalybuka
Subscribers: zhaoqin, llvm-commits, kcc
Differential Revision: http://reviews.llvm.org/D18465
llvm-svn: 264451
On OS X, fork() under TSan asserts (in debug builds only) because REAL(fork) calls some intercepted functions, which check that no internal locks are held via CheckNoLocks(). But the wrapper of fork intentionally holds some locks. This patch fixes that by using ScopedIgnoreInterceptors during the call to REAL(fork). After that, all the fork-based tests seem to pass on OS X, so let's just remove all the UNSUPPORTED: darwin annotations we have.
Differential Revision: http://reviews.llvm.org/D18409
llvm-svn: 264261
Adds strchr, strchrnul, and strrchr to the common interceptors, under a new
common flag intercept_strchr.
Removes the now-duplicate strchr interceptor from asan and all 3
interceptors from tsan. Previously, asan did not intercept strchrnul, but
does now; previously, msan did not intercept strchr, strchrnul, or strrchr,
but does now.
http://reviews.llvm.org/D18329
Patch by Derek Bruening!
llvm-svn: 263992
On OS X, we have pthread_cond_timedwait_relative_np. TSan needs to intercept this API to avoid false positives when using condition variables.
Differential Revision: http://reviews.llvm.org/D18184
llvm-svn: 263782
This patch adds a new TSan report type, ReportTypeMutexInvalidAccess, which is triggered when pthread_mutex_lock or pthread_mutex_unlock returns EINVAL (this means the mutex is invalid, uninitialized or already destroyed).
Differential Revision: http://reviews.llvm.org/D18132
llvm-svn: 263641
Summary:
Adds strlen to the common interceptors, under a new common flag
intercept_strlen. This provides better sharing of interception code among
sanitizers and cleans up the inconsistent type declarations of the
previously duplicated interceptors.
Removes the now-duplicate strlen interceptor from asan, msan, and tsan.
The entry check semantics are normalized now for msan and asan, whose
private strlen interceptors contained multiple layers of checks that
included impossible-to-reach code. The new semantics are identical to the
old: bypass interception if in the middle of init or if both on Mac and not
initialized; else, call the init routine and proceed.
Patch by Derek Bruening!
Reviewers: samsonov, vitalybuka
Subscribers: llvm-commits, kcc, zhaoqin
Differential Revision: http://reviews.llvm.org/D18020
llvm-svn: 263177
Summary:
__BIG_ENDIAN__ and __LITTLE_ENDIAN__ are not supported by gcc, which
eg. for ubsan Value::getFloatValue will silently fall through to
the little endian branch, breaking display of float values by ubsan.
Use __BYTE_ORDER__ == __ORDER_BIG/LITTLE_ENDIAN__ as the condition
instead, which is supported by both clang and gcc.
Noticed while porting ubsan to s390x.
Patch by Marcin Kościelnicki!
Differential Revision: http://reviews.llvm.org/D17660
llvm-svn: 263077
Currently ThreadState holds both logical state (required for race-detection algorithm, user-visible)
and physical state (various caches, most notably malloc cache). Move physical state in a new
Process entity. Besides just being the right thing from abstraction point of view, this solves several
problems:
1. Cache everything on P level in Go. Currently we cache on a mix of goroutine and OS thread levels.
This unnecessary increases memory consumption.
2. Properly handle free operations in Go. Frees are issue by GC which don't have goroutine context.
As the result we could not do anything more than just clearing shadow. For example, we leaked
sync objects and heap block descriptors.
3. This will allow to get rid of libc malloc in Go (now we have Processor context for internal allocator cache).
This in turn will allow to get rid of dependency on libc entirely.
4. Potentially we can make Processor per-CPU in C++ mode instead of per-thread, which will
reduce resource consumption.
The distinction between Thread and Processor is currently used only by Go, C++ creates Processor per OS thread,
which is equivalent to the current scheme.
llvm-svn: 262037
This patch moves recv and recvfrom interceptors from MSan and TSan to
sanitizer_common to enable them in ASan.
Differential Revision: http://reviews.llvm.org/D17479
llvm-svn: 261841
The first issue is that we longjmp from ScopedInterceptor scope
when called from an ignored lib. This leaves thr->in_ignored_lib set.
This, in turn, disables handling of sigaction. This, in turn,
corrupts tsan state since signals delivered asynchronously.
Another issue is that we can ignore synchronization in asignal
handler, if the signal is delivered into an IgnoreSync region.
Since signals are generally asynchronous, they should ignore
memory access/synchronization/interceptor ignores.
This could lead to false positives in signal handlers.
llvm-svn: 261658
Summary:
1. Android doesn't support __thread keyword. So allocate ThreadState
dynamically and store its pointer in one TLS slot provided by Android.
2. On Android, intercepted functions can be called before ThreadState
is initialized. So add test of thr_->is_inited in some places.
3. On Android, intercepted functions can be called after ThreadState
is destroyed. So add a fake dead_thread_state to represent all
destroyed ThreadStates. And that is also why we don't store the pointer
to ThreadState in shadow memory of pthread_self().
Reviewers: kcc, eugenis, dvyukov
Subscribers: kubabrecka, llvm-commits, tberghammer, danalbert, srhines
Differential Revision: http://reviews.llvm.org/D15301
llvm-svn: 257866
Summary:
Android doesn't intercept sigfillset, so REAL(sigfillset) is null.
And we can use internal_sigfillset() for all cases.
Reviewers: kcc, eugenis, kubabrecka, dvyukov
Subscribers: llvm-commits, tberghammer, danalbert
Differential Revision: http://reviews.llvm.org/D15296
llvm-svn: 257862
On OS X, TSan already passes all unit and lit tests, but for real-world applications (even very simple ones), we currently produce a lot of false positive reports about data races. This makes TSan useless at this point, because the noise dominates real bugs. This introduces a runtime flag, "ignore_interceptors_accesses", off by default, which makes TSan ignore all memory accesses that happen from interceptors. This will significantly lower the coverage and miss a lot of bugs, but it eliminates most of the current false positives on OS X.
Differential Revision: http://reviews.llvm.org/D15189
llvm-svn: 257760
The value of the constant PTHREAD_MUTEX_RECURSIVE is not "1" on FreeBSD and OS X.
Differential Revision: http://reviews.llvm.org/D16075
llvm-svn: 257758
Interceptors using ScopedInteceptor should never call into user's code before the ScopedInterceptor is out of scope (and its destructor is called). Let's add a DCHECK to enforce that.
Differential Revision: http://reviews.llvm.org/D15381
llvm-svn: 255996
Some interceptors in tsan_libdispatch_mac.cc currently wrongly use TSAN_SCOPED_INTERCEPTOR/ScopedInterceptor. Its constructor can start ignoring memory accesses, and the destructor the stops this -- however, e.g. dispatch_sync can call user's code, so the ignoring will extend to user's code as well. This is not expected and we should only limit the scope of ScopedInterceptor to TSan code. This patch introduces annotations that mark the beginning and ending of a callback into user's code.
Differential Revision: http://reviews.llvm.org/D15419
llvm-svn: 255995
check_memcpy test added in r254959 fails on some configurations due to
memcpy() calls inserted by Clang. Try harder to avoid them by using
internal_memcpy() where applicable.
llvm-svn: 255287
Summary:
Android doesn't have __libc_malloc and related allocation
functions. As its dynamic linker doesn't use malloc, so
we can use REAL(malloc) to replace __libc_malloc safely.
Reviewers: kcc, eugenis, dvyukov
Subscribers: llvm-commits, tberghammer, danalbert, srhines
Differential Revision: http://reviews.llvm.org/D15297
llvm-svn: 255167
This patch provides the assembly support for setjmp/longjmp for use
with the thread sanitizer. This is a big more complicated than for
aarch64, because sibcalls are only legal under our ABIs if the TOC
pointer is unchanged. Since the true setjmp function trashes the TOC
pointer, and we have to leave the stack in a correct state, we emulate
the setjmp function rather than branching to it.
We also need to materialize the TOC for cases where the _setjmp code
is called from libc. This is done differently under the ELFv1 and
ELFv2 ABIs.
llvm-svn: 255059
This patch is by Simone Atzeni with portions by Adhemerval Zanella.
This contains the LLVM patches to enable the thread sanitizer for
PPC64, both big- and little-endian. Two different virtual memory
sizes are supported: Old kernels use a 44-bit address space, while
newer kernels require a 46-bit address space.
There are two companion patches that will be added shortly. There is
a Clang patch to actually turn on the use of the thread sanitizer for
PPC64. There is also a patch that I wrote to provide interceptor
support for setjmp/longjmp on PPC64.
Patch discussion at reviews.llvm.org/D12841.
llvm-svn: 255057
Another attempt at fixing tsan_invisible_barrier.
Current implementation causes:
https://llvm.org/bugs/show_bug.cgi?id=25643
There were several unsuccessful iterations for this functionality:
Initially it was implemented in user code using REAL(pthread_barrier_wait). But pthread_barrier_wait is not supported on MacOS. Futexes are linux-specific for this matter.
Then we switched to atomics+usleep(10). But usleep produced parasitic "as-if synchronized via sleep" messages in reports which failed some output tests.
Then we switched to atomics+sched_yield. But this produced tons of tsan- visible events, which lead to "failed to restore stack trace" failures.
Move implementation into runtime and use internal_sched_yield in the wait loop.
This way tsan should see no events from the barrier, so not trace overflows and
no "as-if synchronized via sleep" messages.
llvm-svn: 255030
1) There's a few wrongly defined things in tsan_interceptors.cc,
2) a typo in tsan_rtl_amd64.S which calls setjmp instead of sigsetjmp in the interceptor, and
3) on OS X, accessing an mprotected page results in a SIGBUS (and not SIGSEGV).
Differential Revision: http://reviews.llvm.org/D15052
llvm-svn: 254299
This patch ports the assembly file tsan_rtl_amd64.S to OS X, where we need several changes:
* Some assembler directives are not available on OS X (.hidden, .type, .size)
* Symbol names need to start with an underscore (added a ASM_TSAN_SYMBOL macro for that).
* To make the interceptors work, we ween to name the function "_wrap_setjmp" (added ASM_TSAN_SYMBOL_INTERCEPTOR for that).
* Calling the original setjmp is done with a simple "jmp _setjmp".
* __sigsetjmp doesn't exist on OS X.
Differential Revision: http://reviews.llvm.org/D14947
llvm-svn: 254228
This patch fixes the __cxa_guard_acquire, __cxa_guard_release and __cxa_guard_abort interceptors on OS X. They apparently work on Linux just by having the same name, but on OS X, we actually need to use TSAN_INTERCEPTOR.
Differential Revision: http://reviews.llvm.org/D14868
llvm-svn: 253776
On OS X, the thread finalization is fragile due to thread-local variables destruction order. I've seen cases where the we destroy the ThreadState too early and subsequent thread-local values' destructors call interceptors again. Let's replace the TLV-based thread finalization method with libpthread hooks. The notification PTHREAD_INTROSPECTION_THREAD_TERMINATE is called *after* all TLVs have been destroyed.
Differential Revision: http://reviews.llvm.org/D14777
llvm-svn: 253560
Reimplement dispatch_once in an interceptor to solve these issues that may produce false positives with TSan on OS X:
1) there is a racy load inside an inlined part of dispatch_once,
2) the fast path in dispatch_once doesn't perform an acquire load, so we don't properly synchronize the initialization and subsequent uses of whatever is initialized,
3) dispatch_once is already used in a lot of already-compiled code, so TSan doesn't see the inlined fast-path.
This patch uses a trick to avoid ever taking the fast path (by never storing ~0 into the predicate), which means the interceptor will always be called even from already-compiled code. Within the interceptor, our own atomic reads and writes are not written into shadow cells, so the race in the inlined part is not reported (because the accesses are only loads).
Differential Revision: http://reviews.llvm.org/D14811
llvm-svn: 253552
This patch adds assembly routines to enable setjmp/longjmp for aarch64
on linux. It fixes:
* test/tsan/longjmp2.cc
* test/tsan/longjmp3.cc
* test/tsan/longjmp4.cc
* test/tsan/signal_longjmp.cc
I also checked with perlbench from specpu2006 (it fails to run
with missing setjmp/longjmp intrumentation).
llvm-svn: 253205
Fixing `tsan_interceptors.cc`, which on OS X produces a bunch of warnings about unused constants and functions.
Differential Revision: http://reviews.llvm.org/D14381
llvm-svn: 252165
On OS X, memcpy and memmove are actually aliases of the same implementation, which means the interceptor of memcpy is also invoked when memmove is called. The current implementation of the interceptor uses `internal_memcpy` to perform the actual memory operation, which can produce an incorrect result when memmove semantics are expected. Let's call `internal_memmove` instead.
Differential Revision: http://reviews.llvm.org/D14336
llvm-svn: 252162
A call to memmove is used early during new thread initialization on OS X. This patch uses the `COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED` check, similarly to how we deal with other early-used interceptors.
Differential Revision: http://reviews.llvm.org/D14377
llvm-svn: 252161
Marcin Koscielnicki