1 files changed, 174 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp b/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp
new file mode 100644
index 000000000000..7d5a992dc665
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp
@@ -0,0 +1,174 @@
+//===-- tsan_platform_posix.cpp -------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+// POSIX-specific code.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_platform.h"
+#if SANITIZER_POSIX
+
+#  include <dlfcn.h>
+
+#  include "sanitizer_common/sanitizer_common.h"
+#  include "sanitizer_common/sanitizer_errno.h"
+#  include "sanitizer_common/sanitizer_libc.h"
+#  include "sanitizer_common/sanitizer_procmaps.h"
+#  include "tsan_platform.h"
+#  include "tsan_rtl.h"
+
+namespace __tsan {
+
+static const char kShadowMemoryMappingWarning[] =
+    "FATAL: %s can not madvise shadow region [%zx, %zx] with %s (errno: %d)\n";
+static const char kShadowMemoryMappingHint[] =
+    "HINT: if %s is not supported in your environment, you may set "
+    "TSAN_OPTIONS=%s=0\n";
+
+#  if !SANITIZER_GO
+void DontDumpShadow(uptr addr, uptr size) {
+  if (common_flags()->use_madv_dontdump)
+    if (!DontDumpShadowMemory(addr, size)) {
+      Printf(kShadowMemoryMappingWarning, SanitizerToolName, addr, addr + size,
+             "MADV_DONTDUMP", errno);
+      Printf(kShadowMemoryMappingHint, "MADV_DONTDUMP", "use_madv_dontdump");
+      Die();
+    }
+}
+
+void InitializeShadowMemory() {
+  // Map memory shadow.
+  if (!MmapFixedSuperNoReserve(ShadowBeg(), ShadowEnd() - ShadowBeg(),
+                               "shadow")) {
+    Printf("FATAL: ThreadSanitizer can not mmap the shadow memory\n");
+    Printf("FATAL: Make sure to compile with -fPIE and to link with -pie.\n");
+    Die();
+  }
+  // This memory range is used for thread stacks and large user mmaps.
+  // Frequently a thread uses only a small part of stack and similarly
+  // a program uses a small part of large mmap. On some programs
+  // we see 20% memory usage reduction without huge pages for this range.
+  DontDumpShadow(ShadowBeg(), ShadowEnd() - ShadowBeg());
+  DPrintf("memory shadow: %zx-%zx (%zuGB)\n",
+      ShadowBeg(), ShadowEnd(),
+      (ShadowEnd() - ShadowBeg()) >> 30);
+
+  // Map meta shadow.
+  const uptr meta = MetaShadowBeg();
+  const uptr meta_size = MetaShadowEnd() - meta;
+  if (!MmapFixedSuperNoReserve(meta, meta_size, "meta shadow")) {
+    Printf("FATAL: ThreadSanitizer can not mmap the shadow memory\n");
+    Printf("FATAL: Make sure to compile with -fPIE and to link with -pie.\n");
+    Die();
+  }
+  DontDumpShadow(meta, meta_size);
+  DPrintf("meta shadow: %zx-%zx (%zuGB)\n",
+      meta, meta + meta_size, meta_size >> 30);
+
+  InitializeShadowMemoryPlatform();
+
+  on_initialize = reinterpret_cast<void (*)(void)>(
+      dlsym(RTLD_DEFAULT, "__tsan_on_initialize"));
+  on_finalize =
+      reinterpret_cast<int (*)(int)>(dlsym(RTLD_DEFAULT, "__tsan_on_finalize"));
+}
+
+static bool TryProtectRange(uptr beg, uptr end) {
+  CHECK_LE(beg, end);
+  if (beg == end)
+    return true;
+  return beg == (uptr)MmapFixedNoAccess(beg, end - beg);
+}
+
+static void ProtectRange(uptr beg, uptr end) {
+  if (!TryProtectRange(beg, end)) {
+    Printf("FATAL: ThreadSanitizer can not protect [%zx,%zx]\n", beg, end);
+    Printf("FATAL: Make sure you are not using unlimited stack\n");
+    Die();
+  }
+}
+
+// CheckAndProtect will check if the memory layout is compatible with TSan.
+// Optionally (if 'protect' is true), it will set the memory regions between
+// app memory to be inaccessible.
+// 'ignore_heap' means it will not consider heap memory allocations to be a
+// conflict. Set this based on whether we are calling CheckAndProtect before
+// or after the allocator has initialized the heap.
+bool CheckAndProtect(bool protect, bool ignore_heap, bool print_warnings) {
+  // Ensure that the binary is indeed compiled with -pie.
+  MemoryMappingLayout proc_maps(true);
+  MemoryMappedSegment segment;
+  while (proc_maps.Next(&segment)) {
+    if (segment.start >= HeapMemBeg() && segment.end <= HeapEnd()) {
+      if (ignore_heap) {
+        continue;
+      } else {
+        return false;
+      }
+    }
+
+    // Note: IsAppMem includes if it is heap memory, hence we must
+    // put this check after the heap bounds check.
+    if (IsAppMem(segment.start) && IsAppMem(segment.end - 1))
+      continue;
+
+    // Guard page after the heap end
+    if (segment.start >= HeapMemEnd() && segment.start < HeapEnd()) continue;
+
+    if (segment.protection == 0)  // Zero page or mprotected.
+      continue;
+
+    if (segment.start >= VdsoBeg())  // vdso
+      break;
+
+    // Debug output can break tests. Suppress this message in most cases.
+    if (print_warnings)
+      Printf(
+          "WARNING: ThreadSanitizer: unexpected memory mapping 0x%zx-0x%zx\n",
+          segment.start, segment.end);
+
+    return false;
+  }
+
+  if (!protect)
+    return true;
+
+#    if SANITIZER_IOS && !SANITIZER_IOSSIM
+  ProtectRange(HeapMemEnd(), ShadowBeg());
+  ProtectRange(ShadowEnd(), MetaShadowBeg());
+  ProtectRange(MetaShadowEnd(), HiAppMemBeg());
+#    else
+  ProtectRange(LoAppMemEnd(), ShadowBeg());
+  ProtectRange(ShadowEnd(), MetaShadowBeg());
+  if (MidAppMemBeg()) {
+    ProtectRange(MetaShadowEnd(), MidAppMemBeg());
+    ProtectRange(MidAppMemEnd(), HeapMemBeg());
+  } else {
+    ProtectRange(MetaShadowEnd(), HeapMemBeg());
+  }
+  ProtectRange(HeapEnd(), HiAppMemBeg());
+#    endif
+
+#    if defined(__s390x__)
+  // Protect the rest of the address space.
+  const uptr user_addr_max_l4 = 0x0020000000000000ull;
+  const uptr user_addr_max_l5 = 0xfffffffffffff000ull;
+  // All the maintained s390x kernels support at least 4-level page tables.
+  ProtectRange(HiAppMemEnd(), user_addr_max_l4);
+  // Older s390x kernels may not support 5-level page tables.
+  TryProtectRange(user_addr_max_l4, user_addr_max_l5);
+#endif
+
+  return true;
+}
+#  endif
+
+}  // namespace __tsan
+
+#endif  // SANITIZER_POSIX