[all-commits] [llvm/llvm-project] bc949f: [GWP-ASan] Handle wild touches of the guarded pool.

[Mitch Phillips via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: bc949f923ee37e6c71b69d0c0337d0e6b499832d
      https://github.com/llvm/llvm-project/commit/bc949f923ee37e6c71b69d0c0337d0e6b499832d
  Author: Mitch Phillips <31459023+hctim at users.noreply.github.com>
  Date:   2023-02-28 (Tue, 28 Feb 2023)

  Changed paths:
    M compiler-rt/lib/gwp_asan/optional/segv_handler_posix.cpp
    M compiler-rt/lib/gwp_asan/tests/CMakeLists.txt
    M compiler-rt/lib/gwp_asan/tests/backtrace.cpp
    M compiler-rt/lib/gwp_asan/tests/harness.cpp
    M compiler-rt/lib/gwp_asan/tests/harness.h
    A compiler-rt/lib/gwp_asan/tests/never_allocated.cpp
    M compiler-rt/lib/gwp_asan/tests/recoverable.cpp

  Log Message:
  -----------
  [GWP-ASan] Handle wild touches of the guarded pool.

AllocMeta could be null when returned from __gwp_asan_get_metadata() for
a bad access into the GuardedPagePool that was never allocated.
Currently, then we dereference the null pointer, oops.

Hoist the check up and print a message (only once in recoverable mode)
about the bad memory access.

Reviewed By: fmayer

Differential Revision: https://reviews.llvm.org/D144973