Summary: For platforms which support slow unwinder only, we restrict the store context size to 1, basically only storing the current pc. We do this because the slow unwinder which is based on libunwind is not async signal safe and causes random freezes in forking applications as well as in signal handlers.
Reviewed by eugenis.
Differential: D23107
llvm-svn: 289027
This patch adds 48-bits VMA support for msan on aarch64. As current
mappings for aarch64, 48-bit VMA also supports PIE executable. The
48-bits segments only cover the usual PIE/default segments plus some
more segments (262144GB total, 0.39% total VMA). Memory avaliability
can be increase by adding multiple application segments like 39 and
42 mapping (some mappings were added on this patch as well).
Tested on 39 and 48-bit VMA kernels on aarch64.
llvm-svn: 279752
MSan runtime is not itself instrumented, so we need to explicitly
clear shadow for function arguments before calling user-provided
functions from runtime (e.g. we already do this for several
interceptors).
I'm still crafting a test case that would demonstrate this issue
reliably, and will commit it later today.
llvm-svn: 258339
This is an implementation of
https://github.com/google/sanitizers/issues/579
It has a number of advantages over the current mapping:
* Works for non-PIE executables.
* Does not require ASLR; as a consequence, debugging MSan programs in
gdb no longer requires "set disable-randomization off".
* Supports linux kernels >=4.1.2.
* The code is marginally faster and smaller.
This is an ABI break. We never really promised ABI stability, but
this patch includes a courtesy escape hatch: a compile-time macro
that reverts back to the old mapping layout.
llvm-svn: 249754
This patch enabled msan for aarch64 with 39-bit VMA and 42-bit VMA.
As defined by lib/msan/msan.h the memory layout used is for 39-bit is:
00 0000 0000 - 40 0000 0000: invalid
40 0000 0000 - 43 0000 0000: shadow
43 0000 0000 - 46 0000 0000: origin
46 0000 0000 - 55 0000 0000: invalid
55 0000 0000 - 56 0000 0000: app (low)
56 0000 0000 - 70 0000 0000: invalid
70 0000 0000 - 80 0000 0000: app (high)
And for 42-bit VMA:
000 0000 0000 - 100 0000 0000: invalid
100 0000 0000 - 11b 0000 0000: shadow
11b 0000 0000 - 120 0000 0000: invalid
120 0000 0000 - 13b 0000 0000: origin
13b 0000 0000 - 2aa 0000 0000: invalid
2aa 0000 0000 - 2ab 0000 0000: app (low)
2ab 0000 0000 - 3f0 0000 0000: invalid
3f0 0000 0000 - 400 0000 0000: app (high)
Most of tests are passing with exception of:
* Linux/mallinfo.cc
* chained_origin_limits.cc
* dlerror.cc
* param_tls_limit.cc
* signal_stress_test.cc
* nonnull-arg.cpp
The 'Linux/mallinfo.cc' is due the fact AArch64 returns the sret in 'x8'
instead of default first argument 'x1'. So a function prototype that
aims to mimic (by using first argument as the return of function) won't
work. For GCC one can make a register alias (register var asm ("r8")), but
for clang it detects is an unused variable and generate wrong code.
The 'chained_origin_limits' is probably due a wrong code generation,
since it fails only when origin memory is used
(-fsanitize-memory-track-origins=2) and only in the returned code
(return buf[50]).
The 'signal_streess_test' and 'nonnull-arg' are due currently missing variadic
argument handling in memory sanitizer code instrumentation on LLVM side.
Both 'dlerror' and 'param_tls_test' are unknown failures that require
further investigation.
All the failures are XFAIL for aarch64 for now.
llvm-svn: 247809
Previously we had to call __sanitizer_cov_dump() from tool-specific
callbacks - instead, let sanitizer_common library handle this in a
single place.
This is a re-application of r245770, with slightly different approach
taken.
llvm-svn: 245890
These changes break both autoconf Mac OS X buildbot (linker errors
due to wrong Makefiles) and CMake buildbot (safestack test failures).
llvm-svn: 245784
Previously we had to call __sanitizer_cov_dump() from tool-specific
callbacks - instead, let sanitizer_common library handle this in a single place.
llvm-svn: 245770
Summary:
This patch adds basic memory sanitizer support for PPC64. PR23219.
I have further patches ready to enable it in LLVM and Clang, and to fix
most of the many failing tests in check-msan.
Reviewers: kcc, willschm, samsonov, wschmidt, eugenis
Reviewed By: eugenis
Subscribers: wschmidt, llvm-commits
Differential Revision: http://reviews.llvm.org/D10648
llvm-svn: 240623
Fix 2 bugs in memory mapping setup:
- the invalid region at offset 0 was not protected because mmap at
address 0 fails with EPERM on most Linux systems. We did not
notice this because the check condition was flipped: the code was
checking that mprotect has failed. And the test that was supposed
to catch this was weakened by the mitigations in the mmap
interceptor.
- when running without origins, the origin shadow range was left
unprotected.
The new test ensures that mmap w/o MAP_FIXED always returns valid
application addresses.
llvm-svn: 238109
Embed UBSan runtime into TSan and MSan runtimes in the same as we do
in ASan. Extend UBSan test suite to also run tests for these
combinations.
llvm-svn: 235954
A flexible way of describing MSan memory layout details on various
platforms. No significant functional changes, but the memory layout
description that you get at verbosity=1 looks slightly different.
This change includes stronger sanity checks than before.
The goal of this change is to allow more than 2 application memory
ranges for https://code.google.com/p/memory-sanitizer/issues/detail?id=76.
llvm-svn: 227192
By attaching an extra integer tag to heap origins, we are able
to distinguish between uninits
- created by heap allocation,
- created by heap deallocation (i.e. use-after-free),
- created by __msan_allocated_memory call,
- etc.
See https://code.google.com/p/memory-sanitizer/issues/detail?id=35.
llvm-svn: 226821
Summary:
Turn "allocator_may_return_null" common flag into an
Allocator::may_return_null bool flag. We want to make sure
that common flags are immutable after initialization. There
are cases when we want to change this flag in the allocator
at runtime: e.g. in unit tests and during ASan activation
on Android.
Test Plan: regression test suite, real-life applications
Reviewers: kcc, eugenis
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6623
llvm-svn: 224148
MSanDR is a dynamic instrumentation tool that can instrument the code
(prebuilt libraries and such) that could not be instrumented at compile time.
This code is unused (to the best of our knowledge) and unmaintained, and
starting to bit-rot.
llvm-svn: 222232
introduce a BufferedStackTrace class, which owns this array.
Summary:
This change splits __sanitizer::StackTrace class into a lightweight
__sanitizer::StackTrace, which doesn't own array of PCs, and BufferedStackTrace,
which owns it. This would allow us to simplify the interface of StackDepot,
and eventually merge __sanitizer::StackTrace with __tsan::StackTrace.
Test Plan: regression test suite.
Reviewers: kcc, dvyukov
Reviewed By: dvyukov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5985
llvm-svn: 220635
ParamTLS (shadow for function arguments) is of limited size. This change
makes all arguments that do not fit unpoisoned, and avoids writing
past the end of a TLS buffer.
llvm-svn: 220351
Introduce new public header <sanitizer/allocator_interface.h> and a set
of functions __sanitizer_get_ownership(), __sanitizer_malloc_hook() etc.
that will eventually replace their tool-specific equivalents
(__asan_get_ownership(), __msan_get_ownership() etc.). Tool-specific
functions are now deprecated and implemented as stubs redirecting
to __sanitizer_ versions (which are implemented differently in each tool).
Replace all uses of __xsan_ versions with __sanitizer_ versions in unit
and lit tests.
llvm-svn: 212469
Generalize StackDepot and create a new specialized instance of it to
efficiently (i.e. without duplicating stack trace data) store the
origin history tree.
This reduces memory usage for chained origins roughly by an order of
magnitude.
Most importantly, this new design allows us to put two limits on
stored history data (exposed in MSAN_OPTIONS) that help avoid
exponential growth in used memory on certain workloads.
See comments in lib/msan/msan_origin.h for more details.
llvm-svn: 209284
Compiler-rt part of MSan implementation of advanced origin tracking,
when we record not only creation point, but all locations where
an uninitialized value was stored to memory, too.
llvm-svn: 204152
Before we did it lazily on the first stack unwind in the thread.
It resulted in deadlock when the unwind was caused by memory allocation
inside pthread_getattr_np:
pthread_getattr_np <<< not reentable
GetThreadStackTopAndBottom
__interceptor_realloc
pthread_getattr_np
llvm-svn: 197026
Origin copying may destroy valid origin info. This is caused by
__msan_copy_origin widening the address range to the nearest 4-byte aligned
addresses both on the left and on the right. If the target buffer is
uninitialized and the source is fully initialized, this will result in
overriding valid origin of target buffer with stale (possibly 0) origin of the
source buffer.
With this change the widened origin is copied only if corresponding shadow
values are non zero.
llvm-svn: 193338
MSan poisons deallocated memory but it used to give it an invalid origin value,
resulting in confusing reports. This change associates deallocation stack trace
with such memory.
Note that MSan does not have quarantine, and use-after-free detection is very
limited.
llvm-svn: 190781
Sagar Thakur