Commit Graph

3818 Commits

Author SHA1 Message Date
Vitaly Buka 6478ef61b1 [asan] Remove Asan, Ubsan support of RTEMS and Myriad
Differential Revision: https://reviews.llvm.org/D104279
2021-06-15 12:59:05 -07:00
Vitaly Buka b8919fb0ea [NFC][sanitizer] clang-format some code 2021-06-14 18:05:22 -07:00
serge-sans-paille 4144827514 Prevent generation of dependency on _cxa_guard for static initialization
This fixes an issue introduced by https://reviews.llvm.org/D70662

Function-scope static initialization are guarded in C++, so we should probably
not use it because it introduces a dependency on __cxa_guard* symbols.
In the context of clang, libasan is linked statically, and it currently needs to
the odd situation where compiling C code with clang and asan requires -lstdc++

Differential Revision: https://reviews.llvm.org/D102475
2021-06-09 09:38:59 +02:00
Fangrui Song e67259531d [sanitizer] Let glibc aarch64 use O(1) GetTls
The generic approach can still be used by musl and FreeBSD. Note: on glibc
2.31, TLS_PRE_TCB_SIZE is 0x700, larger than ThreadDescriptorSize() by 16, but
this is benign: as long as the range includes pthread::{specific_1stblock,specific}
pthread_setspecific will not cause false positives.

Note: the state before afec953857 underestimated
the TLS size a lot (nearly ThreadDescriptorSize() = 1776).
That may explain why afec953857 actually made some
tests pass.
2021-05-25 16:28:17 -07:00
Vitaly Buka 5992823008 [NFC][sanitizer] Remove unused variable 2021-05-21 16:11:51 -07:00
Vitaly Buka f50b87e9ef [NFC][sanitizer] Fix android bot after D102815
https://lab.llvm.org/buildbot/#/builders/77/builds/6519
2021-05-21 14:08:04 -07:00
George Balatsouras 7c35bf85bf [sanitizer_common] Remove unused var in test
Reviewed By: stephan.yichao.zhao

Differential Revision: https://reviews.llvm.org/D102898
2021-05-20 20:42:30 -07:00
George Balatsouras d10c1ba487 [sanitizer_common] Add StackTrace::PrintTo method
This method is like StackTrace::Print but instead of printing to stderr
it copies its output to a user-provided buffer.

Part of https://reviews.llvm.org/D102451.

Reviewed By: vitalybuka, stephan.yichao.zhao

Differential Revision: https://reviews.llvm.org/D102815
2021-05-20 19:39:38 -07:00
Tamar Christina 68d5235cb5 libsanitizer: Remove cyclades inclusion in sanitizer
The Linux kernel has removed the interface to cyclades from
the latest kernel headers[1] due to them being orphaned for the
past 13 years.

libsanitizer uses this header when compiling against glibc, but
glibcs itself doesn't seem to have any references to cyclades.

Further more it seems that the driver is broken in the kernel and
the firmware doesn't seem to be available anymore.

As such since this is breaking the build of libsanitizer (and so the
GCC bootstrap[2]) I propose to remove this.

[1] https://lkml.org/lkml/2021/3/2/153
[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100379

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D102059
2021-05-20 18:55:26 +01:00
Tamar Christina 0d3619864c Revert "libsanitizer: Guard cyclades inclusion in sanitizer"
This reverts commit f7c5351552.

To investigate a test failure.
2021-05-20 14:43:57 +01:00
Tamar Christina f7c5351552 libsanitizer: Guard cyclades inclusion in sanitizer
The Linux kernel has removed the interface to cyclades from
the latest kernel headers[1] due to them being orphaned for the
past 13 years.

libsanitizer uses this header when compiling against glibc, but
glibcs itself doesn't seem to have any references to cyclades.

Further more it seems that the driver is broken in the kernel and
the firmware doesn't seem to be available anymore.

As such since this is breaking the build of libsanitizer (and so the
GCC bootstrap[2]) I propose to remove this.

[1] https://lkml.org/lkml/2021/3/2/153
[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100379

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D102059
2021-05-20 11:06:56 +01:00
Dmitry Vyukov c1eaa1168a tsan: mark sigwait as blocking
Add a test case reported in:
https://github.com/google/sanitizers/issues/1401
and fix it.
The code assumes sigwait will process other signals.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D102057
2021-05-19 13:03:20 +02:00
Dmitry Vyukov 00a1007545 sanitizer_common/symbolizer: fix crashes during exit
Override __cxa_atexit and ignore callbacks.
This prevents crashes in a configuration when the symbolizer
is built into sanitizer runtime and consequently into the test process.
LLVM libraries have some global objects destroyed during exit,
so if the test process triggers any bugs after that, the symbolizer crashes.
An example stack trace of such crash:

For the standalone llvm-symbolizer this does not hurt,
we just don't destroy few global objects on exit.

Reviewed By: kda

Differential Revision: https://reviews.llvm.org/D102470
2021-05-18 08:58:08 +02:00
Florian Hahn 086af17399
Revert "tsan: mark sigwait as blocking"
This reverts commit 5dad3d1ba9.

The added test (signal_block2.cpp) does not terminate on some Darwin
configurations and is causing Green Dragon bots to fail. First
failure of the test started in
    http://green.lab.llvm.org/green/job/clang-stage1-RA/20767/
2021-05-17 10:57:59 +01:00
Vitaly Buka 029005a2e2 [NFC][sanitizer] Fix 'macro redefined' warning in test 2021-05-16 19:11:07 -07:00
Benjamin Kramer cb846654c6 [compiler-rt] Fix deprection warnings on INSTANTIATE_TEST_CASE_P 2021-05-15 00:24:02 +02:00
Fangrui Song deb2b20510 [sanitizer] Commit a missing change in BufferedStackTrace::Unwind 2021-05-14 12:41:34 -07:00
Fangrui Song fa27255d16 [sanitizer] Fall back to fast unwinder
`-fno-exceptions -fno-asynchronous-unwind-tables` compiled programs don't
produce .eh_frame on Linux and other ELF platforms, so the slow unwinder cannot
print stack traces. Just fall back to the fast unwinder: this allows
-fno-asynchronous-unwind-tables without requiring the sanitizer option
`fast_unwind_on_fatal=1`

Reviewed By: #sanitizers, vitalybuka

Differential Revision: https://reviews.llvm.org/D102046
2021-05-14 12:27:33 -07:00
H.J. Lu 72797dedb7 [sanitizer] Use size_t on g_tls_size to fix build on x32
On x32 size_t == unsigned int, not unsigned long int:

../../../../../src-master/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp: In function ??void __sanitizer::InitTlsSize()??:
../../../../../src-master/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp:209:55: error: invalid conversion from ??__sanitizer::uptr*?? {aka ??long unsigned int*??} to ??size_t*?? {aka ??unsigned int*??} [-fpermissive]
  209 |   ((void (*)(size_t *, size_t *))get_tls_static_info)(&g_tls_size, &tls_align);
      |                                                       ^~~~~~~~~~~
      |                                                       |
      |                                                       __sanitizer::uptr* {aka long unsigned int*}

by using size_t on g_tls_size.  This is to fix:

https://bugs.llvm.org/show_bug.cgi?id=50332

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D102446
2021-05-13 18:07:11 -07:00
Dmitry Vyukov 2721e27c3a sanitizer_common: deduplicate CheckFailed
We have some significant amount of duplication around
CheckFailed functionality. Each sanitizer copy-pasted
a chunk of code. Some got random improvements like
dealing with recursive failures better. These improvements
could benefit all sanitizers, but they don't.

Deduplicate CheckFailed logic across sanitizers and let each
sanitizer only print the current stack trace.
I've tried to dedup stack printing as well,
but this got me into cmake hell. So let's keep this part
duplicated in each sanitizer for now.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D102221
2021-05-12 08:50:53 +02:00
Dmitry Vyukov 23596fece0 sanitizer_common: don't write into .rodata
setlocale interceptor imitates a write into result,
which may be located in .rodata section.
This is the only interceptor that tries to do this and
I think the intention was to initialize the range for msan.
So do that instead. Writing into .rodata shouldn't happen
(without crashing later on the actual write) and this
traps on my local tsan experiments.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D102161
2021-05-12 07:54:06 +02:00
Dmitry Vyukov 53558ed8a0 sanitizer_common: fix SIG_DFL warning
Currently we have:

sanitizer_posix_libcdep.cpp:146:27: warning: cast between incompatible
  function types from ‘__sighandler_t’ {aka ‘void (*)(int)’} to ‘sa_sigaction_t’
  146 |     sigact.sa_sigaction = (sa_sigaction_t)SIG_DFL;

We don't set SA_SIGINFO, so we need to assign to sa_handler.
And SIG_DFL is meant for sa_handler, so this gets rid of both
compiler warning, type cast and potential runtime misbehavior.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D102162
2021-05-12 07:23:20 +02:00
Dmitry Vyukov 5dad3d1ba9 tsan: mark sigwait as blocking
Add a test case reported in:
https://github.com/google/sanitizers/issues/1401
and fix it.
The code assumes sigwait will process other signals.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D102057
2021-05-12 06:56:18 +02:00
Jianzhou Zhao bf4e1cf80a Revert "[sanitizer_common] Recycle StackDepot memory"
This reverts commit 78804e6b20.
2021-05-05 00:57:34 +00:00
Jianzhou Zhao 78804e6b20 [sanitizer_common] Recycle StackDepot memory
This relates to https://reviews.llvm.org/D95835.

In DFSan origin tracking we use StackDepot to record
stack traces and origin traces (like MSan origin tracking).

For at least two reasons, we wanted to control StackDepot's memory cost
1) We may use DFSan origin tracking to monitor programs that run for
   many days. This may eventually use too much memory for StackDepot.
2) DFSan supports flush shadow memory to reduce overhead. After flush,
   all existing IDs in StackDepot are not valid because no one will
   refer to them.
2021-05-05 00:51:45 +00:00
Fangrui Song 2fec8860d8 [sanitizer] Set IndentPPDirectives: AfterHash in .clang-format
Code patterns like this are common, `#` at the line beginning
(https://google.github.io/styleguide/cppguide.html#Preprocessor_Directives),
one space indentation for if/elif/else directives.
```
#if SANITIZER_LINUX
# if defined(__aarch64__)
# endif
#endif
```

However, currently clang-format wants to reformat the code to
```
#if SANITIZER_LINUX
#if defined(__aarch64__)
#endif
#endif
```

This significantly harms readability in my review.  Use `IndentPPDirectives:
AfterHash` to defeat the diagnostic. clang-format will now suggest:

```
#if SANITIZER_LINUX
#  if defined(__aarch64__)
#  endif
#endif
```

Unfortunately there is no clang-format option using indent with 1 for
just preprocessor directives. However, this is still one step forward
from the current behavior.

Reviewed By: #sanitizers, vitalybuka

Differential Revision: https://reviews.llvm.org/D100238
2021-05-03 13:49:41 -07:00
Dmitry Vyukov 92a3a2dc3e sanitizer_common: introduce kInvalidTid/kMainTid
Currently we have a bit of a mess related to tids:
 - sanitizers re-declare kInvalidTid multiple times
 - some call it kUnknownTid
 - implicit assumptions that main tid is 0
 - asan/memprof claim their tids need to fit into 24 bits,
   but this does not seem to be true anymore
 - inconsistent use of u32/int to store tids

Introduce kInvalidTid/kMainTid in sanitizer_common
and use them consistently.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D101428
2021-04-30 15:58:05 +02:00
Leonard Chan a786f2badc [compiler-rt][hwasan] Add definition for Symbolizer::SymbolizeFrame
This is undefined if SANITIZER_SYMBOLIZER_MARKUP is 1, which is the case for
Fuchsia, and will result in a undefined symbol error. This function is needed
by hwasan for online symbolization, but is not needed for us since we do
offline symbolization.

Differential Revision: https://reviews.llvm.org/D99386
2021-04-26 13:25:10 -07:00
Emily Shi 6ae7fc0a29 [compiler-rt] check max address from kernel is <= mmap range size
If these sizes do not match, asan will not work as expected. Previously, we added compile-time checks for non-iOS platforms. We check at run time for iOS because we get the max VM size from the kernel at run time.

rdar://76477969

Reviewed By: delcypher

Differential Revision: https://reviews.llvm.org/D100784
2021-04-21 12:02:48 -07:00
Fangrui Song 031c40dc3c [sanitizer] Fix glibc sparc build and add GetTls support
sanitizer_linux_libcdep.cpp doesn't build for Linux sparc (with minimum support
but can build) after D98926. I wasn't aware because the file didn't mention
`__sparc__`.

While here, add the relevant support since it does not add complexity
(the D99566 approach).  Adds an explicit `#error` for unsupported
non-Android Linux and FreeBSD architectures.

ThreadDescriptorSize is only used by lsan to scan thread-specific data keys in
the thread control block.

On TLS Variant II architectures (i386/x86_64/s390/sparc), our dl_iterate_phdr
based approach can cover the region from the first byte of the static TLS block
(static TLS surplus) to the thread pointer.
We just need to extend the range to include the first few members of struct
pthread. offsetof(struct pthread, specific_used) satisfies the requirement and
has not changed since 2007-05-10. We don't need to update ThreadDescriptorSize
for each glibc version.

Technically we could use the 524/1552 for x86_64 as well but there is potential
risk that large applications with thousands of shared object dependency may
dislike the time complexity increase if there are many threads, so I don't make
the simplification for now.

Differential Revision: https://reviews.llvm.org/D100892
2021-04-20 17:42:41 -07:00
Emily Shi cc2b62a06e [compiler-rt] assert max virtual address is <= mmap range size
If these sizes do not match, asan will not work as expected.

If possible, assert at compile time that the vm size is less than or equal to mmap range.
If a compile time assert is not possible, check at run time (for iOS)

rdar://76477969

Reviewed By: delcypher, yln

Differential Revision: https://reviews.llvm.org/D100239
2021-04-19 14:01:07 -07:00
Emily Shi 94ba3b6e3b [compiler-rt][asan] use full vm range on apple silicon macs
We previously shrunk the mmap range size on ios, but those settings got inherited by apple silicon macs.
Don't shrink the vm range on apple silicon Mac since we have access to the full range.

Also don't shrink vm range for iOS simulators because they have the same range as the host OS, not the simulated OS.

rdar://75302812

Reviewed By: delcypher, kubamracek, yln

Differential Revision: https://reviews.llvm.org/D100234
2021-04-19 12:12:26 -07:00
Sylvestre Ledru 485e561f8d Try to unbreak the compiler-rt build on s390x
Introduced by:
3d1d7156e9
2021-04-19 13:17:47 +02:00
Fangrui Song 3d1d7156e9 [sanitizer] Don't call __tls_get_addr on s390x after D98926
glibc s390x doesn't define __tls_get_addr.

Fix PR50017
2021-04-18 10:42:44 -07:00
Fangrui Song 08843a0c3f [sanitizer] GetTls: work around ppc64 with glibc<2.25(?) or GNU ld 2.30
GNU ld 2.26 and GNU ld 2.31 seem fine but GNU ld 2.30 has mysterious
segfaults linking msan tests.
2021-04-16 14:03:28 -07:00
Vitaly Buka b93629dd33 Address D100645 comment 2021-04-16 11:28:41 -07:00
Vitaly Buka 82150606fb Sanitizer built against glibc 2.34 doesn't work
As mentioned in https://gcc.gnu.org/PR100114 , glibc starting with the
https://sourceware.org/git/?p=glibc.git;a=commit;h=6c57d320484988e87e446e2e60ce42816bf51d53
change doesn't define SIGSTKSZ and MINSIGSTKSZ macros to constants, but to sysconf function call.
sanitizer_posix_libcdep.cpp has
static const uptr kAltStackSize = SIGSTKSZ * 4;  // SIGSTKSZ is not enough.
which is generally fine, just means that when SIGSTKSZ is not a compile time constant will be initialized later.
The problem is that kAltStackSize is used in SetAlternateSignalStack which is called very early, from .preinit_array
initialization, i.e. far before file scope variables are constructed, which means it is not initialized and
mmapping 0 will fail:
==145==ERROR: AddressSanitizer failed to allocate 0x0 (0) bytes of SetAlternateSignalStack (error code: 22)

Here is one possible fix, another one could be to make kAltStackSize a preprocessor macro if _SG_SIGSTKSZ is defined
(but perhaps with having an automatic const variable initialized to it so that sysconf isn't at least called twice
during SetAlternateSignalStack.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D100645
2021-04-16 11:21:03 -07:00
Fangrui Song 376db8eaef [sanitizer] Mark g_use_dlpi_tls_data as unused
There is a -Wunused-variable warning on Android
2021-04-16 09:28:51 -07:00
Fangrui Song afec953857 [sanitizer] Simplify GetTls with dl_iterate_phdr on Linux and use it on musl/FreeBSD
... so that FreeBSD specific GetTls/glibc specific pthread_self code can be
removed. This also helps FreeBSD arm64/powerpc64 which don't have GetTls
implementation yet.

GetTls is the range of

* thread control block and optional TLS_PRE_TCB_SIZE
* static TLS blocks plus static TLS surplus

On glibc, lsan requires the range to include
`pthread::{specific_1stblock,specific}` so that allocations only referenced by
`pthread_setspecific` can be scanned.

This patch uses `dl_iterate_phdr` to collect TLS blocks. Find the one
with `dlpi_tls_modid==1` as one of the initially loaded module, then find
consecutive ranges. The boundaries give us addr and size.

This allows us to drop the glibc internal `_dl_get_tls_static_info` and
`InitTlsSize`. However, huge glibc x86-64 binaries with numerous shared objects
may observe time complexity penalty, so exclude them for now. Use the simplified
method with non-Android Linux for now, but in theory this can be used with *BSD
and potentially other ELF OSes.

This removal of RISC-V `__builtin_thread_pointer` makes the code compilable with
more compiler versions (added in Clang in 2020-03, added in GCC in 2020-07).

This simplification enables D99566 for TLS Variant I architectures.

Note: as of musl 1.2.2 and FreeBSD 12.2, dlpi_tls_data returned by
dl_iterate_phdr is not desired: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=254774
This can be worked around by using `__tls_get_addr({modid,0})` instead
of `dlpi_tls_data`. The workaround can be shared with the workaround for glibc<2.25.

This fixes some tests on Alpine Linux x86-64 (musl)

```
test/lsan/Linux/cleanup_in_tsd_destructor.c
test/lsan/Linux/fork.cpp
test/lsan/Linux/fork_threaded.cpp
test/lsan/Linux/use_tls_static.cpp
test/lsan/many_tls_keys_thread.cpp

test/msan/tls_reuse.cpp
```

and `test/lsan/TestCases/many_tls_keys_pthread.cpp` on glibc aarch64.

The number of sanitizer test failures does not change on FreeBSD/amd64 12.2.

Differential Revision: https://reviews.llvm.org/D98926
2021-04-15 15:34:43 -07:00
Emily Shi 20f38d0142 [compiler-rt] add SANITIZER_OSX
This will allow us to make osx specific changes easier. Because apple silicon macs also run on aarch64, it was easy to confuse it with iOS.

rdar://75302812

Reviewed By: yln

Differential Revision: https://reviews.llvm.org/D100157
2021-04-12 11:45:45 -07:00
James Y Knight 3b1b1d7530 Fix f6ee97d8271e1dfd9b6572222fefe8f40433952e:
PrintAddress needs to be false (as it was before), or this breaks sanitizer backtraces.
2021-04-06 14:10:26 -04:00
Alexander Belyaev f6ee97d827 [rt] Update DIPrinter usage in 'sanitizer_symbolize.cpp`.
These changes were required after
5f57793c4f

Differential Revision: https://reviews.llvm.org/D99937
2021-04-06 12:31:47 +02:00
Nico Weber 0e92cbd6a6 Revert "[sanitizer] Simplify GetTls with dl_iterate_phdr on Linux"
This reverts commit ec575e3b0a.
Still doesn't work, see https://crbug.com/1196037
2021-04-05 19:00:18 -04:00
Fangrui Song ec575e3b0a [sanitizer] Simplify GetTls with dl_iterate_phdr on Linux
This was reverted by f176803ef1 due to
Ubuntu 16.04 x86-64 glibc 2.23 problems.
This commit additionally calls `__tls_get_addr({modid,0})` to work around the
dlpi_tls_data==NULL issues for glibc<2.25
(https://sourceware.org/bugzilla/show_bug.cgi?id=19826)

GetTls is the range of

* thread control block and optional TLS_PRE_TCB_SIZE
* static TLS blocks plus static TLS surplus

On glibc, lsan requires the range to include
`pthread::{specific_1stblock,specific}` so that allocations only referenced by
`pthread_setspecific` can be scanned.

This patch uses `dl_iterate_phdr` to collect TLS blocks. Find the one
with `dlpi_tls_modid==1` as one of the initially loaded module, then find
consecutive ranges. The boundaries give us addr and size.

This allows us to drop the glibc internal `_dl_get_tls_static_info` and
`InitTlsSize` entirely. Use the simplified method with non-Android Linux for
now, but in theory this can be used with *BSD and potentially other ELF OSes.

This simplification enables D99566 for TLS Variant I architectures.

See https://reviews.llvm.org/D93972#2480556 for analysis on GetTls usage
across various sanitizers.

Differential Revision: https://reviews.llvm.org/D98926
2021-04-04 15:35:53 -07:00
Nico Weber f176803ef1 Revert "[sanitizer] Simplify GetTls with dl_iterate_phdr"
This reverts commit 9be8f8b34d.
This breaks tsan on Ubuntu 16.04:

    $ cat tiny_race.c
    #include <pthread.h>
    int Global;
    void *Thread1(void *x) {
      Global = 42;
      return x;
    }
    int main() {
      pthread_t t;
      pthread_create(&t, NULL, Thread1, NULL);
      Global = 43;
      pthread_join(t, NULL);
      return Global;
    }
    $ out/gn/bin/clang -fsanitize=thread -g -O1 tiny_race.c --sysroot ~/src/chrome/src/build/linux/debian_sid_amd64-sysroot/
    $ docker run -v $PWD:/foo ubuntu:xenial /foo/a.out
    FATAL: ThreadSanitizer CHECK failed: ../../compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp:447 "((thr_beg)) >= ((tls_addr))" (0x7fddd76beb80, 0xfffffffffffff980)
        #0 <null> <null> (a.out+0x4960b6)
        #1 <null> <null> (a.out+0x4b677f)
        #2 <null> <null> (a.out+0x49cf94)
        #3 <null> <null> (a.out+0x499bd2)
        #4 <null> <null> (a.out+0x42aaf1)
        #5 <null> <null> (libpthread.so.0+0x76b9)
        #6 <null> <null> (libc.so.6+0x1074dc)

(Get the sysroot from here: https://commondatastorage.googleapis.com/chrome-linux-sysroot/toolchain/500976182686961e34974ea7bdc0a21fca32be06/debian_sid_amd64_sysroot.tar.xz)

Also reverts follow-on commits:
This reverts commit 58c62fd976.
This reverts commit 31e541e375.
2021-04-02 18:19:17 -04:00
Luís Marques eb4967c8bd [Sanitizer][RISCV][AArch64][Android] Adjust allocator tests
On 64-bit systems with small VMAs (e.g. 39-bit) we can't use
SizeClassAllocator64 parameterized with size class maps containing a large
number of classes, as that will make the allocator region size too small
(< 2^32). Several tests were already disabled for Android because of this.

This patch provides the correct allocator configuration for RISC-V
(riscv64), generalizes the gating condition for tests that can't be enabled
for small VMA systems, and tweaks the tests that can be made compatible with
those systems to enable them.

I think the previous gating on Android should instead be AArch64+Android, so
the patch reflects that.

Differential Revision: https://reviews.llvm.org/D97234
2021-03-30 21:20:37 +01:00
Fangrui Song 58c62fd976 [sanitizer] Improve accuracy of GetTls on x86/s390
The previous code may underestimate the static TLS surplus part, which may cause
false positives to LeakSanitizer if a dynamically loaded module uses the surplus
and there is an allocation only referenced by a thread's TLS.
2021-03-29 22:14:29 -07:00
Fangrui Song d3e7ee36f6 [sanitizer] Define MAP_NORESERVE to 0 and hide mremap for FreeBSD 2021-03-27 12:18:58 -07:00
Fangrui Song 31e541e375 [sanitizer] Temporarily switch ppc64 to the _dl_get_tls_static_info implementation
sanitizer-ppc64le-linux is good while clang-ppc64le-linux has test
failures due to GetStaticTlsRange(addr, size) set *addr is 0.
2021-03-26 23:21:47 -07:00
Fangrui Song 9be8f8b34d [sanitizer] Simplify GetTls with dl_iterate_phdr
GetTls is the range of

* thread control block and optional TLS_PRE_TCB_SIZE
* static TLS blocks plus static TLS surplus

On glibc, lsan requires the range to include
`pthread::{specific_1stblock,specific}` so that allocations only referenced by
`pthread_setspecific` can be scanned.

This patch uses `dl_iterate_phdr` to collect TLS ranges. Find the one
with `dlpi_tls_modid==1` as one of the initially loaded module, then find
consecutive ranges. The boundaries give us addr and size.

This allows us to drop the glibc internal `_dl_get_tls_static_info` and
`InitTlsSize` entirely. Use the simplified method with non-Android Linux for
now, but in theory this can be used with *BSD and potentially other ELF OSes.

In the future, we can move `ThreadDescriptorSize` code to lsan (and consider
intercepting `pthread_setspecific`) to avoid hacks in generic code.

See https://reviews.llvm.org/D93972#2480556 for analysis on GetTls usage
across various sanitizers.

Differential Revision: https://reviews.llvm.org/D98926
2021-03-25 21:55:27 -07:00