Summary:
The current code was sometimes attempting to release huge chunks of
memory due to undesired RoundUp/RoundDown interaction when the requested
range is fully contained within one memory page.
Reviewers: eugenis
Subscribers: kubabrecka, llvm-commits
Patch by Aleksey Shlyapnikov.
Differential Revision: https://reviews.llvm.org/D27228
llvm-svn: 288271
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
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
- Trim spaces.
- Use nullptr in place of 0 for pointer variables.
- Use '!p' in place of 'p == 0' for null pointer checks.
- Add blank lines to separate function definitions.
- Add 'extern "C"' or 'namespace foo' comments after the appropriate
closing brackets
This is a continuation of work from 409b7b82. The focus here is on the
various sanitizers (not sanitizer_common, as before).
Patch by Eugene Zelenko!
Differential Revision: http://reviews.llvm.org/D13225
llvm-svn: 248966
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
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
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
Fixes 2 issues in origins arising from realloc() calls:
* In the in-place grow case origin for the new memory is not set at all.
* In the copy-realloc case __msan_memcpy is used, which unwinds stack from
inside the MSan runtime. This does not generally work (as we may be built
w/o frame pointers), and produces "bad" stack trace anyway, with several
uninteresting (internal) frames on top.
This change also makes realloc() honor "zeroise" and "poison_in_malloc" flags.
See https://code.google.com/p/memory-sanitizer/issues/detail?id=73.
llvm-svn: 226674
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
Previously, all origin ids were "chained" origins, i.e values of
ChainedOriginDepot. This added a level of indirection for simple
stack and heap allocation, which were represented as chains of
length 1. This costs both RAM and CPU, but provides a joined 2**29
origin id space. It also made function (any instrumented function)
entry non-async-signal-safe, but that does not really matter because
memory stores in track-origins=2 mode are not async-signal-safe anyway.
With this change, the type of the origin is encoded in origin id.
See comment in msan_origin.h for more details. This reduces chained and stack
origin id range to 2**28 each, but leaves extra 2**31 for heap origins.
This change should not have any user-visible effects.
llvm-svn: 223233
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
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