clang-p2996/compiler-rt/lib/sanitizer_common/sanitizer_libignore.cpp

//===-- sanitizer_libignore.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
//
//===----------------------------------------------------------------------===//

#include "sanitizer_platform.h"

#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_APPLE || \
    SANITIZER_NETBSD

#include "sanitizer_libignore.h"
#include "sanitizer_flags.h"
#include "sanitizer_posix.h"
#include "sanitizer_procmaps.h"

namespace __sanitizer {

LibIgnore::LibIgnore(LinkerInitialized) {
}

void LibIgnore::AddIgnoredLibrary(const char *name_templ) {
  Lock lock(&mutex_);
  if (count_ >= kMaxLibs) {
    Report("%s: too many ignored libraries (max: %zu)\n", SanitizerToolName,
           kMaxLibs);
    Die();
  }
  Lib *lib = &libs_[count_++];
  lib->templ = internal_strdup(name_templ);
  lib->name = nullptr;
  lib->real_name = nullptr;
  lib->range_id = kInvalidCodeRangeId;
}

void LibIgnore::OnLibraryLoaded(const char *name) {
  Lock lock(&mutex_);
  // Try to match suppressions with symlink target.
  InternalMmapVector<char> buf(kMaxPathLength);
  if (name && internal_readlink(name, buf.data(), buf.size() - 1) > 0 &&
      buf[0]) {
    for (uptr i = 0; i < count_; i++) {
      Lib *lib = &libs_[i];
      if (!lib->loaded() && (!lib->real_name) &&
          TemplateMatch(lib->templ, name))
        lib->real_name = internal_strdup(buf.data());
    }
  }

  // Scan suppressions list and find newly loaded and unloaded libraries.
  ListOfModules modules;
  modules.init();
  for (uptr i = 0; i < count_; i++) {
    Lib *lib = &libs_[i];
    bool loaded = false;
    for (const auto &mod : modules) {
      for (const auto &range : mod.ranges()) {
        if (!range.executable)
          continue;
        if (!TemplateMatch(lib->templ, mod.full_name()) &&
            !(lib->real_name &&
            internal_strcmp(lib->real_name, mod.full_name()) == 0))
          continue;
        if (loaded) {
          Report("%s: called_from_lib suppression '%s' is matched against"
                 " 2 libraries: '%s' and '%s'\n",
                 SanitizerToolName, lib->templ, lib->name, mod.full_name());
          Die();
        }
        loaded = true;
        if (lib->loaded())
          continue;
        VReport(1,
                "Matched called_from_lib suppression '%s' against library"
                " '%s'\n",
                lib->templ, mod.full_name());
        lib->name = internal_strdup(mod.full_name());
        const uptr idx =
            atomic_load(&ignored_ranges_count_, memory_order_relaxed);
        CHECK_LT(idx, ARRAY_SIZE(ignored_code_ranges_));
        ignored_code_ranges_[idx].OnLoad(range.beg, range.end);
        // Record the index of the ignored range.
        lib->range_id = idx;
        atomic_store(&ignored_ranges_count_, idx + 1, memory_order_release);
        break;
      }
    }
    if (lib->loaded() && !loaded) {
      VReport(1,
              "%s: library '%s' that was matched against called_from_lib"
              " suppression '%s' is unloaded\n",
              SanitizerToolName, lib->name, lib->templ);
      // The library is unloaded so mark the ignored code range as unloaded.
      ignored_code_ranges_[lib->range_id].OnUnload();
      lib->range_id = kInvalidCodeRangeId;
    }
  }

  // Track instrumented ranges.
  if (track_instrumented_libs_) {
    for (const auto &mod : modules) {
      if (!mod.instrumented())
        continue;
      for (const auto &range : mod.ranges()) {
        if (!range.executable)
          continue;
        if (IsPcInstrumented(range.beg) && IsPcInstrumented(range.end - 1))
          continue;
        VReport(1, "Adding instrumented range %p-%p from library '%s'\n",
                (void *)range.beg, (void *)range.end, mod.full_name());
        const uptr idx =
            atomic_load(&instrumented_ranges_count_, memory_order_relaxed);
        CHECK_LT(idx, ARRAY_SIZE(instrumented_code_ranges_));
        instrumented_code_ranges_[idx].OnLoad(range.beg, range.end);
        atomic_store(&instrumented_ranges_count_, idx + 1,
                     memory_order_release);
      }
    }
  }
}

void LibIgnore::OnLibraryUnloaded() {
  OnLibraryLoaded(nullptr);
}

} // namespace __sanitizer

#endif  // SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_APPLE ||
        // SANITIZER_NETBSD