5 Commits

Author SHA1 Message Date
Vitaly Buka
f13b7d0b02
Reland "[sanitizer] Fix partially initialized static TLS range" (#108883)
Reland llvm/llvm-project#108685

Arguments order was wrong on Windows and Darwin.
2024-09-16 14:05:00 -07:00
Vitaly Buka
9a1d0744ed
Revert "[sanitizer] Fix partially initialized static TLS range" (#108881)
Reverts llvm/llvm-project#108685

Breaks Darwin and Windows
https://lab.llvm.org/buildbot/#/builders/107/builds/2930
https://ci.swift.org/view/all/job/llvm.org/view/LLDB/job/as-lldb-cmake/11684/
2024-09-16 13:51:23 -07:00
Vitaly Buka
b7c9ebe4ec
[sanitizer] Fix partially initialized static TLS range (#108685)
Fixes asan, msan crash on check added in #108684.
The #108684 includes reproducer of the issue.

Change interface of `GetThreadStackAndTls` to
set `tls_begin` and `tls_end` at the same time.
2024-09-16 12:48:24 -07:00
Fangrui Song
652707a645
[nsan] Use sanitizer allocator
* The performance is better than the glibc allocator.
* Allocator interface functions, sanitizer allocator options, and
  MallocHooks/FreeHooks are supported.
* Shadow memory has specific memory layout requirement. Using libc
  allocator could lead to conflicts.
* When we add a mmap interceptor for reliability (the VMA could reuse a
  previously released VMA that is poisoned): glibc may invoke an
  internal system call to call unmmap, which cannot be intercepted. We
  will not be able to return the shadow memory to the OS.

Similar to dfsan https://reviews.llvm.org/D101204 . Also intercept
operator new/delete to be similar to other sanitizers using the
sanitizer allocator. The align_val_t overload of operator new has
slightly less overhead.

Pull Request: https://github.com/llvm/llvm-project/pull/102764
2024-08-12 13:56:40 -07:00
Fangrui Song
249db518e3
[nsan] Add NsanThread and clear static TLS shadow
On thread creation, asan/hwasan/msan/tsan unpoison the thread stack and
static TLS blocks in case the blocks reuse previously freed memory that
is possibly poisoned. glibc nptl/allocatestack.c allocates thread stack
using a hidden, non-interceptable function.

nsan is similar: the shadow types for the thread stack and static TLS
blocks should be set to unknown, otherwise if the static TLS blocks
reuse previous shadow memory, and `*p += x` instead of `*p = x` is used
for the first assignment, the mismatching user and shadow memory could
lead to false positives.

NsanThread is also needed by the next patch to use the sanitizer
allocator.

Pull Request: https://github.com/llvm/llvm-project/pull/102718
2024-08-11 10:53:18 -07:00