Summary:
Objective-C employs tagged pointers, that is, small objects/values may be encoded directly in the pointer bits. The resulting pointer is not backed by an allocation/does not point to a valid memory. TSan infrastructure requires a valid address for `Acquire/Release` and `Mutex{Lock/Unlock}`.
This patch establishes such a mapping via a "dummy allocation" for each encountered tagged pointer value.
Reviewers: dcoughlin, kubamracek, dvyukov, delcypher
Reviewed By: dvyukov
Subscribers: llvm-commits, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D56238
llvm-svn: 350556
This is the deprecated legacy interface, replace it with the current
_zx_vmar_allocate one.
Differential Revision: https://reviews.llvm.org/D56360
llvm-svn: 350488
We still need the interceptor on non-aarch64 to untag the pthread_t
and pthread_attr_t pointers and disable tagging on allocations done
internally by glibc.
llvm-svn: 350445
Summary:
The default setting kTabSizeLog=20 results in an 8Mb global hash table,
almost all of it in private pages. That is not a sane setting in a
mobile, system-wide use case: with ~150 concurrent processes stack
depot will account for more than 1Gb of RAM.
Reviewers: kcc, pcc
Subscribers: srhines, kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D56333
llvm-svn: 350443
The problem is similar to D55986 but for threads: a process with the
interceptor hwasan library loaded might have some threads started by
instrumented libraries and some by uninstrumented libraries, and we
need to be able to run instrumented code on the latter.
The solution is to perform per-thread initialization lazily. If a
function needs to access shadow memory or add itself to the per-thread
ring buffer its prologue checks to see whether the value in the
sanitizer TLS slot is null, and if so it calls __hwasan_thread_enter
and reloads from the TLS slot. The runtime does the same thing if it
needs to access this data structure.
This change means that the code generator needs to know whether we
are targeting the interceptor runtime, since we don't want to pay
the cost of lazy initialization when targeting a platform with native
hwasan support. A flag -fsanitize-hwaddress-abi={interceptor,platform}
has been introduced for selecting the runtime ABI to target. The
default ABI is set to interceptor since it's assumed that it will
be more common that users will be compiling application code than
platform code.
Because we can no longer assume that the TLS slot is initialized,
the pthread_create interceptor is no longer necessary, so it has
been removed.
Ideally, lazy initialization should only cost one instruction in the
hot path, but at present the call may cause us to spill arguments
to the stack, which means more instructions in the hot path (or
theoretically in the cold path if the spills are moved with shrink
wrapping). With an appropriately chosen calling convention for
the per-thread initialization function (TODO) the hot path should
always need just one instruction and the cold path should need two
instructions with no spilling required.
Differential Revision: https://reviews.llvm.org/D56038
llvm-svn: 350429
The Android dynamic loader has a non-standard feature that allows
libraries such as the hwasan runtime to interpose symbols even after
the symbol already has a value. The new value of the symbol is used to
relocate libraries loaded after the interposing library, but existing
libraries keep the old value. This behaviour is activated by the
DF_1_GLOBAL flag in DT_FLAGS_1, which is set by passing -z global to
the linker, which is what we already do to link the hwasan runtime.
What this means in practice is that if we have .so files that depend
on interceptor-mode hwasan without the main executable depending on
it, some of the libraries in the process will be using the hwasan
allocator and some will be using the system allocator, and these
allocators need to interact somehow. For example, if an instrumented
library calls a function such as strdup that allocates memory on
behalf of the caller, the instrumented library can reasonably expect
to be able to call free to deallocate the memory.
We can handle that relatively easily with hwasan by using tag 0 to
represent allocations from the system allocator. If hwasan's realloc
or free functions are passed a pointer with tag 0, the system allocator
is called.
One limitation is that this scheme doesn't work in reverse: if an
instrumented library allocates memory, it must free the memory itself
and cannot pass ownership to a system library. In a future change,
we may want to expose an API for calling the system allocator so
that instrumented libraries can safely transfer ownership of memory
to system libraries.
Differential Revision: https://reviews.llvm.org/D55986
llvm-svn: 350427
Summary:
Replace the 32-bit allocator with a 64-bit one with a non-constant
base address, and reduce both the number of size classes and the maximum
size of per-thread caches.
As measured on [1], this reduces average weighted memory overhead
(MaxRSS) from 26% to 12% over stock android allocator. These numbers
include overhead from code instrumentation and hwasan shadow (i.e. not a
pure allocator benchmark).
This switch also enables release-to-OS functionality, which is not
implemented in the 32-bit allocator. I have not seen any effect from
that on the benchmark.
[1] https://android.googlesource.com/platform/system/extras/+/master/memory_replay/
Reviewers: vitalybuka, kcc
Subscribers: kubamracek, cryptoad, llvm-commits
Differential Revision: https://reviews.llvm.org/D56239
llvm-svn: 350370
Implement the interceptors for popen(), pclose() and popenve()
functions. The first two are POSIX, the third one is specific
to NetBSD. popen() spawns a process and creates a FILE object piping
data from/to that process. pclose() closes the pipe and waits for
the process to terminate appropriately.
For the purpose of popen(), the COMMON_INTERCEPTOR_FILE_OPEN macro is
modified to allow null path parameter.
Differential Revision: https://reviews.llvm.org/D56157
llvm-svn: 350232
Update the interceptor for devname_r() to account for correct return
types on different platforms. This function returns int on NetBSD
but char* on FreeBSD/OSX. Noticed by @krytarowski.
Differential Revision: https://reviews.llvm.org/D56150
llvm-svn: 350228
Summary:
Change the point of calling MaybeStartBackgroudThread() from AsanInitInternal()
that is too early on NetBSD to a constructor (with aid of C++11 lambda construct).
Enable the code for background thread as is for NetBSD.
Rename test/sanitizer_common/TestCases/Linux/hard_rss_limit_mb_test.cc
to test/sanitizer_common/TestCases/hard_rss_limit_mb_test.cc and allow runs
on NetBSD. This tests passes correctly.
Reviewers: vitalybuka, joerg, eugenis
Reviewed By: eugenis
Subscribers: eugenis, kubamracek, fedor.sergeev, llvm-commits, mgorny, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D55887
llvm-svn: 350139
Summary:
This is a follow-up to r346956 (https://reviews.llvm.org/D53975).
The purpose of this change to allow implementers of the
`AddressSpaceView` to be able to distinguish between when a caller wants
read-only memory and when a caller wants writable memory. Being able
distinguish these cases allows implementations to optimize for the
different cases and also provides a way to workaround possible platform
restrictions (e.g. the low level platform interface for reading
out-of-process memory may place memory in read-only pages).
For allocator enumeration in almost all cases read-only is sufficient so
we make `Load(...)` take on this new requirement and introduce the
`LoadWritable(...)` variants for cases where memory needs to be
writable.
The behaviour of `LoadWritable(...)` documented in comments are
deliberately very restrictive so that it will be possible in the future
to implement a simple write-cache (i.e. just a map from target address
to a writable region of memory). These restrictions can be loosened in
the future if necessary by implementing a more sophisticated
write-cache.
rdar://problem/45284065
Reviewers: kcc, cryptoad, eugenis, kubamracek, george.karpenkov
Subscribers: #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D54879
llvm-svn: 350136
- Disabled on purpose on Android and Darwin platform (for now).
- Darwin supports it, would need interception in its specific code before enabling it.
- Linux does not support it but only via third party library.
- Android supports it via bionic however it is known to have issue with older versions of the implementations. Can be enabled by an Android committer later on if necessary once there is more 'certainity'/been more tested.
Reviewers: krytarowski, vitalybuka
Reviewed By: krytarowski
Differential Revision: https://reviews.llvm.org/D56125
llvm-svn: 350123
Revert r350104 "[asan] Fix build on windows."
Revert r350101 "[asan] Support running without /proc."
These changes break Mac build, too.
llvm-svn: 350112
Add SIOCSETHERCAP.
Add commented out NVMM (NetBSD Virtual Machine Monitor) operations
as this interface is still WIP and a subject to change.
llvm-svn: 350107
Summary: They happen to work out of the box.
Reviewers: rtrieu, vitalybuka
Subscribers: kubamracek, fedor.sergeev, krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D56088
llvm-svn: 350103
Summary:
Thread Static Data cannot be used in early init on NetBSD
and FreeBSD. Reuse the MSan TSD API for compatibility with
existing code with an alternative implementation using Thread
Local Storage.
New version uses Thread Local Storage to store a pointer
with thread specific data. The destructor from TSD has been
replaced with a TLS destrucutor that is called upon thread
exit.
Reviewers: joerg, vitalybuka, jfb
Reviewed By: vitalybuka
Subscribers: emaste, jfb, llvm-commits, #sanitizers, mgorny
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D55703
llvm-svn: 350102
Summary:
This patch lets ASan run when /proc is not accessible (ex. not mounted
yet). It includes a special test-only flag that emulates this condition
in an unpriviledged process.
This only matters on Linux, where /proc is necessary to enumerate
virtual memory mappings.
Reviewers: pcc, vitalybuka
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D55874
llvm-svn: 350101
Summary: Assigning an array of bools to {false, false, false} can, in certain build configurations, lead to a memset call. Use internal_memset to avoid this.
Reviewers: eugenis
Subscribers: kubamracek, delcypher, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D56107
llvm-svn: 350098
Add a CheckMPROTECT() routine to detect when pax MPROTECT is enabled
on NetBSD, and error xray out when it is. The solution is adapted
from existing CheckASLR().
Differential Revision: https://reviews.llvm.org/D56049
llvm-svn: 350030
Disable enforcing alignas() for structs that are used as thread_local
data on NetBSD. The NetBSD ld.so implementation is buggy and does
not enforce correct alignment; however, clang seems to take it for
granted and generates instructions that segv on wrongly aligned objects.
Therefore, disable those alignas() statements on NetBSD until we can
establish a better fix.
Apparently, std::aligned_storage<> does not have any real effect
at the moment, so we can leave it as-is.
Differential Revision: https://reviews.llvm.org/D56000
llvm-svn: 350029
Reviewers: krytarowski
Reviewed By: krytarowski
Differential Revision: https://reviews.llvm.org/D56009
M lib/sanitizer_common/sanitizer_common_interceptors.inc
M lib/sanitizer_common/sanitizer_platform_interceptors.h
M lib/sanitizer_common/sanitizer_platform_limits_freebsd.cc
M lib/sanitizer_common/sanitizer_platform_limits_freebsd.h
D test/sanitizer_common/TestCases/NetBSD/regex.cc
A + test/sanitizer_common/TestCases/Posix/regex.cc
llvm-svn: 350002
Summary:
NetBSD uses typical UNIX interfaces.
All tests pass except instrprof-dlopen-dlclose-gcov.test, as there
is not supported semantics of atexit(3) in dlopen(3)ed+dlclose(3)d
DSO.
NetBSD also ships an older version of LLVM profile (ABI v.2 predating
ABI v.4 in upstream version) inside libc. That copy has been manually
removed during the porting and testing process of the upstream version
to NetBSD. Otherwise there were conflicts between them two.
Reviewers: joerg, vitalybuka, vsk
Subscribers: srhines, fedor.sergeev, llvm-commits, mgorny, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D55997
llvm-svn: 349994
It should be at the class scope and not inside the `Init(...)` function
because we want to error out as soon as the wrong type is constructed.
At the function scope the `static_assert` is only checked if the
function might be called.
This is a follow up to r349957.
rdar://problem/45284065
llvm-svn: 349960
It should be at the class scope and not inside the `Init(...)` function
because we want to error out as soon as the wrong type is constructed.
At the function scope the `static_assert` is only checked if the
function might be called.
This is a follow up to r349138.
rdar://problem/45284065
llvm-svn: 349959
Summary:
This is a follow up to https://reviews.llvm.org/D55764 .
For the ASan and LSan allocatorsthe type declarations have been modified
so that it's possible to create a combined allocator type that
consistently uses a different type of `AddressSpaceView`. We intend to
use this in future patches. For the other sanitizers they just use
`LocalAddressSpaceView` by default because we have no plans to use these
allocators in an out-of-process manner.
rdar://problem/45284065
Reviewers: kcc, dvyukov, vitalybuka, cryptoad, eugenis, kubamracek, george.karpenkov, yln
Subscribers: #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D55766
llvm-svn: 349957
Summary:
This is a follow up patch to r349138.
This patch makes a `AddressSpaceView` a type declaration in the
allocator parameters used by `SizeClassAllocator64`. For ASan, LSan, and
the unit tests the AP64 declarations have been made templated so that
`AddressSpaceView` can be changed at compile time. For the other
sanitizers we just hard-code `LocalAddressSpaceView` because we have no
plans to use these allocators in an out-of-process manner.
rdar://problem/45284065
Reviewers: kcc, dvyukov, vitalybuka, cryptoad, eugenis, kubamracek, george.karpenkov
Subscribers: #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D55764
llvm-svn: 349954
Add a code to properly test for presence of LLVMTestingSupport library
when performing a stand-alone build, and skip tests requiring it when
it is not present. Since the library is not installed, llvm-config
reported empty --libs for it and the tests failed to link with undefined
references. Skipping the two fdr_* test files is better than failing to
build, and should be good enough until we find a better solution.
NB: both installing LLVMTestingSupport and building it automatically
from within compiler-rt sources are non-trivial. The former due to
dependency on gtest, the latter due to tight integration with LLVM
source tree.
Differential Revision: https://reviews.llvm.org/D55891
llvm-svn: 349899
Summary:
Support running with no open file descriptors (as may happen to
"init" process on linux).
* Remove a check that writing to stderr succeeds.
* When opening a file (ex. for log_path option), dup the new fd out of
[0, 2] range to avoid confusing the program.
(2nd attempt, this time without the sanitizer_rtems change)
Reviewers: pcc, vitalybuka
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D55801
llvm-svn: 349817
This is patch complements D55117 implementing __hwasan_mem*
functions in runtime
Differential revision: https://reviews.llvm.org/D55554
llvm-svn: 349730
Summary:
Support running with no open file descriptors (as may happen to
"init" process on linux).
* Remove a check that writing to stderr succeeds.
* When opening a file (ex. for log_path option), dup the new fd out of
[0, 2] range to avoid confusing the program.
Reviewers: pcc, vitalybuka
Subscribers: kubamracek, llvm-commits
Differential Revision: https://reviews.llvm.org/D55801
llvm-svn: 349699
Summary:
An extra ';' at the end of a namespace triggers a pedantic warning:
```
.../sanitizer_common/sanitizer_type_traits.h:42:2: warning: extra ‘;’ [-Wpedantic]
}; // namespace __sanitizer
```
Reviewers: eugenis, delcypher
Reviewed By: eugenis
Subscribers: kubamracek, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D55849
llvm-svn: 349666