On Darwin, we currently use forkpty to communicate with the "atos" symbolizer. There are several problems that fork or forkpty has, e.g. that after fork, interceptors are still active and this sometimes causes crashes or hangs. This is especially problematic for TSan, which uses interceptors for OS-provided locks and mutexes, and even Libc functions use those.
This patch replaces forkpty with posix_spawn. Since posix_spawn doesn't fork (at least on Darwin), the interceptors are not a problem. Additionally, this also fixes a latent threading problem with ptsname (it's unsafe to use this function in multithreaded programs). Yet another benefit is that we'll handle post-fork failures (e.g. sandbox disallows "exec") gracefully now.
Differential Revision: https://reviews.llvm.org/D40032
llvm-svn: 324846
Summary:
InitializeSwiftDemangler() attempts to resolve the
swift_demangle symbol. If this is not available, we
observe dlerror message leak.
Caught on NetBSD/amd64 in TSan.
Sponsored by <The NetBSD Foundation>
Reviewers: joerg, kubamracek, vitalybuka, dvyukov, eugenis
Reviewed By: dvyukov
Subscribers: llvm-commits, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D40382
llvm-svn: 318980
This fixes a bug in the ReadFromSymbolizer method of the
Addr2LineProcess class; if the input is too large, the returned buffer
will be null and will consequently fail the CHECK. The proposed fix is
to simply check if the buffer consists of only a null-terminator and
return if so (in effect skipping that frame). I tested by running one of
the unit tests both before and after my change.
Submitted on behalf of david-y-lam.
Reviewers: eugenis, alekseyshl, kcc
Reviewed By: alekseyshl
Differential Revision: https://reviews.llvm.org/D36207
llvm-svn: 310089
atos is the default symbolizer on Apple's compiler for quite a few years now.
llvm-symbolizer is quite fragile on Darwin: for example, unless a .dSYM
file was explicitly generated symbolication would not work.
It is also very convenient when the behavior of LLVM open source
compiler matches to that of Apple's compiler on Apple's platform.
Furthermore, llvm-symbolizer is not installed on Apple's platform by
default, which leads to strange behavior during debugging: the test
might fail under lit (where it has llvm-symbolizer) but would run
properly when launched on the command line (where it does not, and atos
would be used).
Indeed, there's a downside: atos does not work properly with inlined
functions, hence the test change.
We do not think that this is a major problem, as users would often
compile with -O0 when debugging, and in any case it is preferable to
symbolizer not being able to symbolize.
Differential Revision: https://reviews.llvm.org/D35745
llvm-svn: 308908
Summary:
This is a pure refactoring change. It just moves code that is
related to filesystem operations from sanitizer_common.{cc,h} to
sanitizer_file.{cc,h}. This makes it cleaner to disable the
filesystem-related code for a new port that doesn't want it.
Submitted on behalf of Roland McGrath.
Reviewers: kcc, eugenis, alekseyshl
Reviewed By: alekseyshl
Subscribers: vitalybuka, llvm-commits, kubamracek, mgorny, phosek
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D35591
llvm-svn: 308819
This is a pure refactoring change. It just moves code that is
related to filesystem operations from sanitizer_common.{cc,h} to
sanitizer_file.{cc,h}. This makes it cleaner to disable the
filesystem-related code for a new port that doesn't want it.
Commiting for mcgrathr.
Reviewers: alekseyshl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35591
llvm-svn: 308640
Summary:
Move cached allocator_may_return_null flag to sanitizer_allocator.cc and
provide API to consolidate and unify the behavior of all specific allocators.
Make all sanitizers using CombinedAllocator to follow
AllocatorReturnNullOrDieOnOOM() rules to behave the same way when OOM
happens.
When OOM happens, turn allocator_out_of_memory flag on regardless of
allocator_may_return_null flag value (it used to not to be set when
allocator_may_return_null == true).
release_to_os_interval_ms and rss_limit_exceeded will likely be moved to
sanitizer_allocator.cc too (later).
Reviewers: eugenis
Subscribers: srhines, kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D34310
llvm-svn: 305858
Summary: The function computes full module name and coverts pc into offset.
Reviewers: kcc
Subscribers: kubabrecka
Differential Revision: https://reviews.llvm.org/D26820
llvm-svn: 288711
TSan runtime shouldn't contain memset, so internal_memset is used
instead and syntax that emits memset is avoided.
This doesn't fail in-tree due to TSan being build with -03, but it fails
when TSan is built with -O0, and is (I think) a true positive.
Patch by Sam McCall, review: https://reviews.llvm.org/D27407
llvm-svn: 288672
On macOS, we often symbolicate using atos (when llvm-symbolizer is not found). The current way we invoke atos involves creating a pseudo-terminal to make sure atos doesn't buffer its output. This however also makes atos think that it's stdin is interactive and in some error situations it will ask the user to enter some input instead of just printing out an error message. For example, when Developer Mode isn't enabled on a machine, atos cannot examine processes, and it will ask the user to enter an administrator's password, which will make the sanitized process get stuck. This patch only connects the pseudo-terminal to the stdout of atos, and uses a regular pipe as its stdin.
Differential Revision: https://reviews.llvm.org/D27239
llvm-svn: 288624
The introduction of the Swift demangler now causes an assertion failure when we
try to demangle nullptr, but we used to allow that (and return nullptr back).
This situation is rare, but it can still happen. Let's allow nullptr.
llvm-svn: 269302
To invoke the Swift demangler, we use dlsym to locate swift_demangle. However, dlsym malloc's storage and stores it in thread-local storage. Since allocations from the symbolizer are done with the system allocator (at least in TSan, interceptors are skipped when inside the symbolizer), we will crash when we try to deallocate later using the sanitizer allocator again.
To fix this, let's just not call dlsym from the demangler, and call it during initialization. The dlsym function calls malloc, so it needs to be only used after our allocator is initialized. Adding a Symbolizer::LateInitialize call that is only invoked after all other initializations.
Differential Revision: http://reviews.llvm.org/D20015
llvm-svn: 269291
To invoke the Swift demangler, we use dlsym to locate swift_demangle. However, dlsym malloc's storage and stores it in thread-local storage. Since allocations from the symbolizer are done with the system allocator (at least in TSan, interceptors are skipped when inside the symbolizer), we will crash when we try to deallocate later using the sanitizer allocator again.
To fix this, let's just not call dlsym from the demangler, and call it during initialization.
Differential Revision: http://reviews.llvm.org/D19974
llvm-svn: 268716
Add support for Swift names when symbolicating sanitizer traces. This is
now relevant since TSan and ASan support have been added to Swift on OS X.
Differential Revision: http://reviews.llvm.org/D19135
llvm-svn: 266494
In `AtosSymbolizer`, we're using `forkpty()` to create a new pseudo-terminal to communicate with the `atos` tool (we need that to avoid output buffering in interactive mode). This however redirects both stdout and stderr into a single stream, so when we read the output, we can't distinguish between errors and standard replies. Let's save&restore stderr to avoid that.
Differential Revision: http://reviews.llvm.org/D15073
llvm-svn: 265923
Summary:
In r251553, I added a warning that proved to be super noisy,
especially in case of MSan. Removing it for now, and I will
probably add some additional diagnostics for symbolizer, when
I better understand how to make it properly.
Reviewers: eugenis
Differential Revision: http://reviews.llvm.org/D14998
llvm-svn: 254102
On Linux, we have internal_fork that forks without invoking user's pthread_atfork handlers, which is important for spawning external symbolizers. Let's implement this for OS X as well (using __fork). This patch also adds internal_forkpty which re-implements forkpty and uses __fork in it as well.
Differential Revision: http://reviews.llvm.org/D14869
llvm-svn: 253666
I noticed that when a symbol is named just "x", it gets demangled to "long long". On POSIX, AFAIK, mangled names always start with "_Z", so lets just require that.
Differential Revision: http://reviews.llvm.org/D14637
llvm-svn: 253080
Summary:
I have othen been stuck when I got an ASAN report, but no symbols
are resolved. The reasons might be different, and it always
requires a bit of detective work to track down.
These more verbose error messages will help the users like me.
Reviewers: samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14135
llvm-svn: 251553
Summary:
llvm-symbolizer understands both PDBs and DWARF, so it's a better bet if
it's available. It prints out the function parameter types and column
numbers, so I needed to churn the expected test output a bit.
This makes most of the llvm-symbolizer subprocessing code
target-independent. Pipes on all platforms use fd_t, and we can use the
portable ReadFromFile / WriteToFile wrappers in symbolizer_sanitizer.cc.
Only the pipe creation and process spawning is Windows-specific.
Please check that the libcdep layering is still correct. I don't know
how to reproduce the build configuration that relies on that.
Reviewers: samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11791
llvm-svn: 244616
I have no idea how to directly test that as it depends on a particular
(micro-)architecure of the host processor.
Combined with llvm's r240339 this should fix issues people might have
be seeing intermitently on Darwin haswell machines (the symbolizer
would use the wrong slice of the binary, thus potentially resolving
to the wrong symbol).
llvm-svn: 240379
The two subclasses of Symbolizer now only define two virtual functions, PlatformDemangle and PlatformPrepareForSandboxing. Let's make these non-virtual and directly defined by individual platforms.
Reviewed at http://reviews.llvm.org/D8912
llvm-svn: 234690
The patch is generated using clang-tidy misc-use-override check.
This command was used:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
-checks='-*,misc-use-override' -header-filter='llvm|clang' -j=32 -fix \
-format
llvm-svn: 234680
Moving the implementation of several functions from sanitizer_symbolizer.cc into sanitizer_symbolizer_libcdep.cc.
Reviewed at http://reviews.llvm.org/D8858
llvm-svn: 234472
It was happening when we looked up a PC for a module that was dlopen'ed/dlclose'd
after the last time we fetched the list of modules
Reviewed at http://reviews.llvm.org/D8618
llvm-svn: 233257
On OS X, dladdr() provides mangled names only, so we need need to demangle in
DlAddrSymbolizer::SymbolizePC.
Reviewed at http://reviews.llvm.org/D8291
llvm-svn: 232910
This patch changes the symbolizer chain on OS X (which currently only uses 1
symbolizer at most) to use this behavior:
* By default, use LLVMSymbolizer -> DlAddrSymbolizer.
* If the llvm-symbolizer binary is not found, use AtosSymbolizer
-> DlAddrSymbolizer.
* If the user specifies ASAN_SYMBOLIZER_PATH=.../atos, then use AtosSymbolizer
-> DlAddrSymbolizer.
* If neither llvm-symbolizer or atos is found, or external symbolication is
disabled with ASAN_SYMBOLIZER_PATH="", use DlAddrSymbolizer.
Reviewed at http://reviews.llvm.org/D8285
llvm-svn: 232908
Kuba Mracek