Summary:
This update introduces i386 support for the Scudo Hardened Allocator, and
offers software alternatives for functions that used to require hardware
specific instruction sets. This should make porting to new architectures
easier.
Among the changes:
- The chunk header has been changed to accomodate the size limitations
encountered on 32-bit architectures. We now fit everything in 64-bit. This
was achieved by storing the amount of unused bytes in an allocation rather
than the size itself, as one can be deduced from the other with the help
of the GetActuallyAllocatedSize function. As it turns out, this header can
be used for both 64 and 32 bit, and as such we dropped the requirement for
the 128-bit compare and exchange instruction support (cmpxchg16b).
- Add 32-bit support for the checksum and the PRNG functions: if the SSE 4.2
instruction set is supported, use the 32-bit CRC32 instruction, and in the
XorShift128, use a 32-bit based state instead of 64-bit.
- Add software support for CRC32: if SSE 4.2 is not supported, fallback on a
software implementation.
- Modify tests that were not 32-bit compliant, and expand them to cover more
allocation and alignment sizes. The random shuffle test has been deactivated
for linux-i386 & linux-i686 as the 32-bit sanitizer allocator doesn't
currently randomize chunks.
Reviewers: alekseyshl, kcc
Subscribers: filcab, llvm-commits, tberghammer, danalbert, srhines, mgorny, modocache
Differential Revision: https://reviews.llvm.org/D26358
llvm-svn: 288255
__sanitizer_contiguous_container_find_bad_address computes three regions of a
container to check for poisoning: begin, middle, end. The issue is that in current
design the first region can be significantly larger than kMaxRangeToCheck.
Proposed patch fixes a typo to calculate the first region properly.
Patch by Ivan Baravy.
Differential Revision: https://reviews.llvm.org/D27061
llvm-svn: 288234
Summary: In profile data paths, we replace "%h" with the hostname of the machine the program is running on. On Windows, we used gethostname() to obtain the hostname. This requires linking with ws2_32. With this change, we instead get the hostname from GetComputerNameExW(), which does not require ws2_32.
Reviewers: rnk, vsk, amccarth
Subscribers: zturner, ruiu, hans
Differential Revision: https://reviews.llvm.org/D27178
llvm-svn: 288146
This fixes an incorrect standard usage of GNU99 when the compiler check was for
the ISO standard C99. Furthermore, bump the dependency up to C11. The
motivation for this change is ARM EHABI compatibility with clang 3.8. We rely
on a type definition redefinition which causes an error with -Werror builds.
This is problematic for FreeBSD builds. Switching to C11 allows the
compatibility without the unnecessary pedantic warning. The alternative would
be to clutter the support header with a `pragma clang diagnostic ignore`. GCC
4.8+ and the supported clang revisions along with MSVC support enough of C11 to
allow building the builtins in C11 mode. No functional change intended.
llvm-svn: 288099
Summary:
In order to avoid starting a separate thread to return unused memory to
the system (the thread interferes with process startup on Android,
Zygota waits for all threads to exit before fork, but this thread never
exits), try to return it right after free.
Reviewers: eugenis
Subscribers: cryptoad, filcab, danalbert, kubabrecka, llvm-commits
Patch by Aleksey Shlyapnikov.
Differential Revision: https://reviews.llvm.org/D27003
llvm-svn: 288091
See D19555 for rationale. As it turns out, this treatment is also necessary
for scanf/printf.
Differential Revision: https://reviews.llvm.org/D27118
llvm-svn: 288064
Handling SIGILL on Darwin works fine, so let's just make this feature work and re-enable the ill.cc testcase.
Differential Revision: https://reviews.llvm.org/D27141
llvm-svn: 287959
This patch prints out all CPU registers after a SIGSEGV. These are available in the signal handler context. Only implemented for Darwin. Can be turned off with the dump_registers flag.
Differential Revision: https://reviews.llvm.org/D11365
llvm-svn: 287957
Summary:
This implements a simple buffer queue to manage a pre-allocated queue of
fixed-sized buffers to hold XRay records. We need this to support
Flight Data Recorder (FDR) mode. We also implement this as a sub-library
first to allow for development before actually using it in an
implementation.
Some important properties of the buffer queue:
- Thread-safe enqueueing/dequeueing of fixed-size buffers.
- Pre-allocation of buffers at construction.
Reviewers: majnemer, rSerge, echristo
Subscribers: mehdi_amini, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D26232
llvm-svn: 287910
GCD queues can be suspended and resumed with dispatch_suspend and dispatch_resume. We need to add synchronization between the call to dispatch_resume and any subsequent executions of blocks in the queue that was resumed. We already have an Acquire(q) before the block executes, so this patch just adds the Release(q) in an interceptor of dispatch_resume.
Differential Revision: https://reviews.llvm.org/D27112
llvm-svn: 287902
The MSVC incremental linker pads every global out to 256 bytes in case
it changes size after an incremental link. So, skip over null entries in
the DSO-wide asan globals array. This only works if the global padding
size is divisible by the size of the asan global object, so add some
defensive CHECKs.
llvm-svn: 287780
This goes through all the calls to `Report(...)` to make sure that each
one would have a newline at the end of the message for readability.
llvm-svn: 287736
/proc/self/maps can't be read atomically, this leads to episodic
crashes in libignore as it thinks that a module is loaded twice.
See the new test for an example.
dl_iterate_phdr does not have this problem.
Switch libignore to dl_iterate_phdr.
llvm-svn: 287632
When building with clang/LLVM in MSVC mode, the msvcrt libraries contain
these functions.
When building in a mingw environment, we need to provide them somehow,
e.g. via compiler-rt.
The aeabi divmod functions work in the same way as the corresponding
__rt_*div* functions for windows, but their parameters are swapped.
The functions for converting float to integer and vice versa are the
same as their aeabi equivalents, only with different function names.
Differential Revision: https://reviews.llvm.org/D26183
llvm-svn: 287465
Summary: The new name better corresponds to its logic.
Reviewers: kcc
Subscribers: kubabrecka
Differential Revision: https://reviews.llvm.org/D26821
llvm-svn: 287377
When the C unwinding personality was corrected to match the ARM EHABI
specification, the unwind header in clang was updated with necessary
declarations. However, when building with an older compiler, we would not have
the necessary declarations. This would result in a build failure. Provide a
supplementary header to ensure that the necessary declarations are present for
the build of the C unwinding personality.
Note that this is NOT an ABI break. It merely is a compile time failure due to
the constants not being present. The constants here are reproduced
equivalently. This header should permit building with clang[<3.9] as well as
gcc.
Addresses PR31035!
llvm-svn: 287359
Summary:
The expectation is that new instrumented code will add global variable
metadata to the .ASAN$GL section, and we will use this new code to
iterate over it.
This technique seems to break when using incremental linking, which
seems to align every global to a 256 byte boundary. Presumably this is
so that it can incrementally cope with global changing size. Clang
already passes -incremental:no as a linker flag when you invoke it to do
the link step.
The two tests added for this feature will fail until the LLVM
instrumentation change in D26770 lands, so they are marked XFAIL for
now.
Reviewers: pcc, kcc, mehdi_amini, kubabrecka
Subscribers: llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D26771
llvm-svn: 287246
Use the __SSE2__ to determine whether SSE2 is enabled in the ASAN tests
rather than relying on either of the __i686__ and __x86_64__. The former
is only set with explicit -march=i686, and therefore misses most of
the x86 CPUs that support SSE2. __SSE2__ is in turn defined if
the current settings (-march, -msse2) indicate that SSE2 is supported
which should be more reliable.
Differential Revision: https://reviews.llvm.org/D26763
llvm-svn: 287245
Include xray_defs.h in xray_arm.cc (seems to be the only one that doesn't
include it).
Buildbot errors:
[...]/compiler-rt/lib/xray/xray_arm.cc:31:58: error: expected initializer before 'XRAY_NEVER_INSTRUMENT'
inline static uint32_t getMovwMask(const uint32_t Value) XRAY_NEVER_INSTRUMENT {
llvm-svn: 287089
Summary:
Adds a CMake check for whether the compiler used to build the XRay
library supports XRay-instrumentation. If the compiler we're using does
support the `-fxray-instrument` flag (i.e. recently-built Clang), we
define the XRAY_NEVER_INSTRUMENT macro that then makes sure that the
XRay runtime functions never get XRay-instrumented.
This prevents potential weirdness involved with building the XRay
library with a Clang that supports XRay-instrumentation, and is
attempting to XRay-instrument the build of compiler-rt.
Reviewers: majnemer, rSerge, echristo
Subscribers: mehdi_amini, llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D26597
llvm-svn: 287068
Users often have their own unhandled exception filters installed. ASan
already goes to great lengths to install its own filter, but our core
wars with Chrome crashpad have escalated to the point that its time to
declare a truce. By exposing this hook, they can call us directly when
they want ASan crash reporting without worrying about who initializes
when.
llvm-svn: 287040
On Darwin, we're running the TSan unit tests without interceptors. To make sure TSan observes all the pthread events (thread creating, thread join, condvar signal, etc.) in tsan_posix.cc, we should call the pthread interceptors directly, as we already do in tsan_test_util_posix.cc. This fixes some flaky failures on Darwin bots.
Differential Revision: https://reviews.llvm.org/D26639
llvm-svn: 287026
Summary:
In a 32-bit address space, PC-relative jump targets are wrapped, so a
direct branch at 0x90000001 can reach address 0x10000000 with a
displacement of 0x7FFFFFFFF. This can happen in applications, such as
Chrome, that are linked with /LARGEADDRESSAWARE.
Reviewers: etienneb
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D26650
llvm-svn: 286997
This adds support for TSan C++ exception handling, where we need to add extra calls to __tsan_func_exit when a function is exitted via exception mechanisms. Otherwise the shadow stack gets corrupted (leaked). This patch moves and enhances the existing implementation of EscapeEnumerator that finds all possible function exit points, and adds extra EH cleanup blocks where needed.
Differential Revision: https://reviews.llvm.org/D26177
llvm-svn: 286894
Summary:
ASan needs to initialize before ucrtbase.dll so that it can intercept
all of its heap allocations. New versions of dbghelp.dll depend on
ucrtbase.dll, which means both of those DLLs will initialize before the
dynamic ASan runtime. By lazily loading dbghelp.dll with LoadLibrary, we
avoid the issue.
Eventually, I would like to remove our dbghelp.dll dependency in favor
of always using llvm-symbolizer.exe, but this seems like an acceptable
interim solution.
Fixes PR30903
Reviewers: etienneb
Subscribers: kubabrecka, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D26473
llvm-svn: 286848
Summary:
In non-strict mode we will check memory access for both strings from beginning
to either:
1. 0-char
2. size
3. different chars
In strict mode we will check from beginning to either:
1. 0-char
2. size
Previously in strict mode we always checked up to the 0-char.
Reviewers: kcc, eugenis
Subscribers: llvm-commits, kubabrecka
Differential Revision: https://reviews.llvm.org/D26574
llvm-svn: 286708
This patch is needed to implement the function attribute that disable TSan checking at run time.
Differential Revision: https://reviews.llvm.org/D25859
llvm-svn: 286658
Now that we use TerminateProcess, the debugger doesn't stop on program
exit. Add this breakpoint so that the debugger stops after asan reports
an error and is prepared to exit the program.
llvm-svn: 286501
ExitProcess still runs some code which can lead to ASan interceptors
running after CHECK failure. This can lead to deadlock if it CHECK fails
again. Avoid that mess by really exiting immediately.
llvm-svn: 286395
Summary:
User applications may register hooks in the .CRT$XL* callback list,
which is called very early by the loader. This is very common in
Chromium:
https://cs.chromium.org/search/?q=CRT.XL&sq=package:chromium&type=cs
This has flown under the radar for a long time because the loader
appears to catch exceptions originating from these callbacks. It's a
real problem when you're debugging an asan application, though, since it
makes the program crash early.
The solution is to add our own callback to this list, and sort it very
early in the list like we do elsewhere. Also add a test with such an
instrumented callback, and test that it gets called with asan.
Reviewers: etienneb
Subscribers: llvm-commits, kubabrecka
Differential Revision: https://reviews.llvm.org/D26404
llvm-svn: 286290
Atomic stores terminate release sequences on the atomic variable,
and must use ReleaseStore primitive instead of Release.
This was broken in r192355 during a refactoring.
Restore correct behavior and add a test.
llvm-svn: 286211
asan_device_setup script is using LD_PRELOAD to inject the ASan
runtime library into the Zygote process. This breaks when the Zygote
or any of its descendants spawn a process with different bitness due
to the fact that the ASan-RT library name includes the target
architecture.
The fix is to preload the library through a symlink which has the
same name in lib and lib64.
llvm-svn: 286188
Only tests using %clang_cl_asan were using the dynamic CRT before this.
The unit tests and lit tests using %clangxx_asan were using the static
CRT. Many cross-platform tests fail with the dynamic CRT, so I had to
add win32-(static|dynamic)-asan lit features.
Also deletes some redundant tests in TestCases/Windows that started
failing with this switch.
llvm-svn: 285821