1 files changed, 557 insertions, 0 deletions

diff --git a/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp b/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp
new file mode 100644
index 000000000000..3b19a6836ec5
--- /dev/null
+++ b/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cpp
@@ -0,0 +1,557 @@
+//===-- sanitizer_symbolizer_libcdep.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 shared between AddressSanitizer and ThreadSanitizer
+// run-time libraries.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_allocator_internal.h"
+#include "sanitizer_internal_defs.h"
+#include "sanitizer_symbolizer_internal.h"
+
+namespace __sanitizer {
+
+Symbolizer *Symbolizer::GetOrInit() {
+  SpinMutexLock l(&init_mu_);
+  if (symbolizer_)
+    return symbolizer_;
+  symbolizer_ = PlatformInit();
+  CHECK(symbolizer_);
+  return symbolizer_;
+}
+
+// See sanitizer_symbolizer_markup.cpp.
+#if !SANITIZER_SYMBOLIZER_MARKUP
+
+const char *ExtractToken(const char *str, const char *delims, char **result) {
+  uptr prefix_len = internal_strcspn(str, delims);
+  *result = (char*)InternalAlloc(prefix_len + 1);
+  internal_memcpy(*result, str, prefix_len);
+  (*result)[prefix_len] = '\0';
+  const char *prefix_end = str + prefix_len;
+  if (*prefix_end != '\0') prefix_end++;
+  return prefix_end;
+}
+
+const char *ExtractInt(const char *str, const char *delims, int *result) {
+  char *buff;
+  const char *ret = ExtractToken(str, delims, &buff);
+  if (buff != 0) {
+    *result = (int)internal_atoll(buff);
+  }
+  InternalFree(buff);
+  return ret;
+}
+
+const char *ExtractUptr(const char *str, const char *delims, uptr *result) {
+  char *buff;
+  const char *ret = ExtractToken(str, delims, &buff);
+  if (buff != 0) {
+    *result = (uptr)internal_atoll(buff);
+  }
+  InternalFree(buff);
+  return ret;
+}
+
+const char *ExtractSptr(const char *str, const char *delims, sptr *result) {
+  char *buff;
+  const char *ret = ExtractToken(str, delims, &buff);
+  if (buff != 0) {
+    *result = (sptr)internal_atoll(buff);
+  }
+  InternalFree(buff);
+  return ret;
+}
+
+const char *ExtractTokenUpToDelimiter(const char *str, const char *delimiter,
+                                      char **result) {
+  const char *found_delimiter = internal_strstr(str, delimiter);
+  uptr prefix_len =
+      found_delimiter ? found_delimiter - str : internal_strlen(str);
+  *result = (char *)InternalAlloc(prefix_len + 1);
+  internal_memcpy(*result, str, prefix_len);
+  (*result)[prefix_len] = '\0';
+  const char *prefix_end = str + prefix_len;
+  if (*prefix_end != '\0') prefix_end += internal_strlen(delimiter);
+  return prefix_end;
+}
+
+SymbolizedStack *Symbolizer::SymbolizePC(uptr addr) {
+  BlockingMutexLock l(&mu_);
+  const char *module_name;
+  uptr module_offset;
+  ModuleArch arch;
+  SymbolizedStack *res = SymbolizedStack::New(addr);
+  if (!FindModuleNameAndOffsetForAddress(addr, &module_name, &module_offset,
+                                         &arch))
+    return res;
+  // Always fill data about module name and offset.
+  res->info.FillModuleInfo(module_name, module_offset, arch);
+  for (auto &tool : tools_) {
+    SymbolizerScope sym_scope(this);
+    if (tool.SymbolizePC(addr, res)) {
+      return res;
+    }
+  }
+  return res;
+}
+
+bool Symbolizer::SymbolizeData(uptr addr, DataInfo *info) {
+  BlockingMutexLock l(&mu_);
+  const char *module_name;
+  uptr module_offset;
+  ModuleArch arch;
+  if (!FindModuleNameAndOffsetForAddress(addr, &module_name, &module_offset,
+                                         &arch))
+    return false;
+  info->Clear();
+  info->module = internal_strdup(module_name);
+  info->module_offset = module_offset;
+  info->module_arch = arch;
+  for (auto &tool : tools_) {
+    SymbolizerScope sym_scope(this);
+    if (tool.SymbolizeData(addr, info)) {
+      return true;
+    }
+  }
+  return true;
+}
+
+bool Symbolizer::SymbolizeFrame(uptr addr, FrameInfo *info) {
+  BlockingMutexLock l(&mu_);
+  const char *module_name;
+  if (!FindModuleNameAndOffsetForAddress(
+          addr, &module_name, &info->module_offset, &info->module_arch))
+    return false;
+  info->module = internal_strdup(module_name);
+  for (auto &tool : tools_) {
+    SymbolizerScope sym_scope(this);
+    if (tool.SymbolizeFrame(addr, info)) {
+      return true;
+    }
+  }
+  return true;
+}
+
+bool Symbolizer::GetModuleNameAndOffsetForPC(uptr pc, const char **module_name,
+                                             uptr *module_address) {
+  BlockingMutexLock l(&mu_);
+  const char *internal_module_name = nullptr;
+  ModuleArch arch;
+  if (!FindModuleNameAndOffsetForAddress(pc, &internal_module_name,
+                                         module_address, &arch))
+    return false;
+
+  if (module_name)
+    *module_name = module_names_.GetOwnedCopy(internal_module_name);
+  return true;
+}
+
+void Symbolizer::Flush() {
+  BlockingMutexLock l(&mu_);
+  for (auto &tool : tools_) {
+    SymbolizerScope sym_scope(this);
+    tool.Flush();
+  }
+}
+
+const char *Symbolizer::Demangle(const char *name) {
+  BlockingMutexLock l(&mu_);
+  for (auto &tool : tools_) {
+    SymbolizerScope sym_scope(this);
+    if (const char *demangled = tool.Demangle(name))
+      return demangled;
+  }
+  return PlatformDemangle(name);
+}
+
+bool Symbolizer::FindModuleNameAndOffsetForAddress(uptr address,
+                                                   const char **module_name,
+                                                   uptr *module_offset,
+                                                   ModuleArch *module_arch) {
+  const LoadedModule *module = FindModuleForAddress(address);
+  if (module == nullptr)
+    return false;
+  *module_name = module->full_name();
+  *module_offset = address - module->base_address();
+  *module_arch = module->arch();
+  return true;
+}
+
+void Symbolizer::RefreshModules() {
+  modules_.init();
+  fallback_modules_.fallbackInit();
+  RAW_CHECK(modules_.size() > 0);
+  modules_fresh_ = true;
+}
+
+static const LoadedModule *SearchForModule(const ListOfModules &modules,
+                                           uptr address) {
+  for (uptr i = 0; i < modules.size(); i++) {
+    if (modules[i].containsAddress(address)) {
+      return &modules[i];
+    }
+  }
+  return nullptr;
+}
+
+const LoadedModule *Symbolizer::FindModuleForAddress(uptr address) {
+  bool modules_were_reloaded = false;
+  if (!modules_fresh_) {
+    RefreshModules();
+    modules_were_reloaded = true;
+  }
+  const LoadedModule *module = SearchForModule(modules_, address);
+  if (module) return module;
+
+  // dlopen/dlclose interceptors invalidate the module list, but when
+  // interception is disabled, we need to retry if the lookup fails in
+  // case the module list changed.
+#if !SANITIZER_INTERCEPT_DLOPEN_DLCLOSE
+  if (!modules_were_reloaded) {
+    RefreshModules();
+    module = SearchForModule(modules_, address);
+    if (module) return module;
+  }
+#endif
+
+  if (fallback_modules_.size()) {
+    module = SearchForModule(fallback_modules_, address);
+  }
+  return module;
+}
+
+// For now we assume the following protocol:
+// For each request of the form
+//   <module_name> <module_offset>
+// passed to STDIN, external symbolizer prints to STDOUT response:
+//   <function_name>
+//   <file_name>:<line_number>:<column_number>
+//   <function_name>
+//   <file_name>:<line_number>:<column_number>
+//   ...
+//   <empty line>
+class LLVMSymbolizerProcess : public SymbolizerProcess {
+ public:
+  explicit LLVMSymbolizerProcess(const char *path)
+      : SymbolizerProcess(path, /*use_posix_spawn=*/SANITIZER_MAC) {}
+
+ private:
+  bool ReachedEndOfOutput(const char *buffer, uptr length) const override {
+    // Empty line marks the end of llvm-symbolizer output.
+    return length >= 2 && buffer[length - 1] == '\n' &&
+           buffer[length - 2] == '\n';
+  }
+
+  // When adding a new architecture, don't forget to also update
+  // script/asan_symbolize.py and sanitizer_common.h.
+  void GetArgV(const char *path_to_binary,
+               const char *(&argv)[kArgVMax]) const override {
+#if defined(__x86_64h__)
+    const char* const kSymbolizerArch = "--default-arch=x86_64h";
+#elif defined(__x86_64__)
+    const char* const kSymbolizerArch = "--default-arch=x86_64";
+#elif defined(__i386__)
+    const char* const kSymbolizerArch = "--default-arch=i386";
+#elif defined(__aarch64__)
+    const char* const kSymbolizerArch = "--default-arch=arm64";
+#elif defined(__arm__)
+    const char* const kSymbolizerArch = "--default-arch=arm";
+#elif defined(__powerpc64__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+    const char* const kSymbolizerArch = "--default-arch=powerpc64";
+#elif defined(__powerpc64__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+    const char* const kSymbolizerArch = "--default-arch=powerpc64le";
+#elif defined(__s390x__)
+    const char* const kSymbolizerArch = "--default-arch=s390x";
+#elif defined(__s390__)
+    const char* const kSymbolizerArch = "--default-arch=s390";
+#else
+    const char* const kSymbolizerArch = "--default-arch=unknown";
+#endif
+
+    const char *const inline_flag = common_flags()->symbolize_inline_frames
+                                        ? "--inlining=true"
+                                        : "--inlining=false";
+    int i = 0;
+    argv[i++] = path_to_binary;
+    argv[i++] = inline_flag;
+    argv[i++] = kSymbolizerArch;
+    argv[i++] = nullptr;
+  }
+};
+
+LLVMSymbolizer::LLVMSymbolizer(const char *path, LowLevelAllocator *allocator)
+    : symbolizer_process_(new(*allocator) LLVMSymbolizerProcess(path)) {}
+
+// Parse a <file>:<line>[:<column>] buffer. The file path may contain colons on
+// Windows, so extract tokens from the right hand side first. The column info is
+// also optional.
+static const char *ParseFileLineInfo(AddressInfo *info, const char *str) {
+  char *file_line_info = 0;
+  str = ExtractToken(str, "\n", &file_line_info);
+  CHECK(file_line_info);
+
+  if (uptr size = internal_strlen(file_line_info)) {
+    char *back = file_line_info + size - 1;
+    for (int i = 0; i < 2; ++i) {
+      while (back > file_line_info && IsDigit(*back)) --back;
+      if (*back != ':' || !IsDigit(back[1])) break;
+      info->column = info->line;
+      info->line = internal_atoll(back + 1);
+      // Truncate the string at the colon to keep only filename.
+      *back = '\0';
+      --back;
+    }
+    ExtractToken(file_line_info, "", &info->file);
+  }
+
+  InternalFree(file_line_info);
+  return str;
+}
+
+// Parses one or more two-line strings in the following format:
+//   <function_name>
+//   <file_name>:<line_number>[:<column_number>]
+// Used by LLVMSymbolizer, Addr2LinePool and InternalSymbolizer, since all of
+// them use the same output format.
+void ParseSymbolizePCOutput(const char *str, SymbolizedStack *res) {
+  bool top_frame = true;
+  SymbolizedStack *last = res;
+  while (true) {
+    char *function_name = 0;
+    str = ExtractToken(str, "\n", &function_name);
+    CHECK(function_name);
+    if (function_name[0] == '\0') {
+      // There are no more frames.
+      InternalFree(function_name);
+      break;
+    }
+    SymbolizedStack *cur;
+    if (top_frame) {
+      cur = res;
+      top_frame = false;
+    } else {
+      cur = SymbolizedStack::New(res->info.address);
+      cur->info.FillModuleInfo(res->info.module, res->info.module_offset,
+                               res->info.module_arch);
+      last->next = cur;
+      last = cur;
+    }
+
+    AddressInfo *info = &cur->info;
+    info->function = function_name;
+    str = ParseFileLineInfo(info, str);
+
+    // Functions and filenames can be "??", in which case we write 0
+    // to address info to mark that names are unknown.
+    if (0 == internal_strcmp(info->function, "??")) {
+      InternalFree(info->function);
+      info->function = 0;
+    }
+    if (0 == internal_strcmp(info->file, "??")) {
+      InternalFree(info->file);
+      info->file = 0;
+    }
+  }
+}
+
+// Parses a two-line string in the following format:
+//   <symbol_name>
+//   <start_address> <size>
+// Used by LLVMSymbolizer and InternalSymbolizer.
+void ParseSymbolizeDataOutput(const char *str, DataInfo *info) {
+  str = ExtractToken(str, "\n", &info->name);
+  str = ExtractUptr(str, " ", &info->start);
+  str = ExtractUptr(str, "\n", &info->size);
+}
+
+static void ParseSymbolizeFrameOutput(const char *str,
+                                      InternalMmapVector<LocalInfo> *locals) {
+  if (internal_strncmp(str, "??", 2) == 0)
+    return;
+
+  while (*str) {
+    LocalInfo local;
+    str = ExtractToken(str, "\n", &local.function_name);
+    str = ExtractToken(str, "\n", &local.name);
+
+    AddressInfo addr;
+    str = ParseFileLineInfo(&addr, str);
+    local.decl_file = addr.file;
+    local.decl_line = addr.line;
+
+    local.has_frame_offset = internal_strncmp(str, "??", 2) != 0;
+    str = ExtractSptr(str, " ", &local.frame_offset);
+
+    local.has_size = internal_strncmp(str, "??", 2) != 0;
+    str = ExtractUptr(str, " ", &local.size);
+
+    local.has_tag_offset = internal_strncmp(str, "??", 2) != 0;
+    str = ExtractUptr(str, "\n", &local.tag_offset);
+
+    locals->push_back(local);
+  }
+}
+
+bool LLVMSymbolizer::SymbolizePC(uptr addr, SymbolizedStack *stack) {
+  AddressInfo *info = &stack->info;
+  const char *buf = FormatAndSendCommand(
+      "CODE", info->module, info->module_offset, info->module_arch);
+  if (buf) {
+    ParseSymbolizePCOutput(buf, stack);
+    return true;
+  }
+  return false;
+}
+
+bool LLVMSymbolizer::SymbolizeData(uptr addr, DataInfo *info) {
+  const char *buf = FormatAndSendCommand(
+      "DATA", info->module, info->module_offset, info->module_arch);
+  if (buf) {
+    ParseSymbolizeDataOutput(buf, info);
+    info->start += (addr - info->module_offset); // Add the base address.
+    return true;
+  }
+  return false;
+}
+
+bool LLVMSymbolizer::SymbolizeFrame(uptr addr, FrameInfo *info) {
+  const char *buf = FormatAndSendCommand(
+      "FRAME", info->module, info->module_offset, info->module_arch);
+  if (buf) {
+    ParseSymbolizeFrameOutput(buf, &info->locals);
+    return true;
+  }
+  return false;
+}
+
+const char *LLVMSymbolizer::FormatAndSendCommand(const char *command_prefix,
+                                                 const char *module_name,
+                                                 uptr module_offset,
+                                                 ModuleArch arch) {
+  CHECK(module_name);
+  if (arch == kModuleArchUnknown) {
+    if (internal_snprintf(buffer_, kBufferSize, "%s \"%s\" 0x%zx\n",
+                          command_prefix, module_name,
+                          module_offset) >= static_cast<int>(kBufferSize)) {
+      Report("WARNING: Command buffer too small");
+      return nullptr;
+    }
+  } else {
+    if (internal_snprintf(buffer_, kBufferSize, "%s \"%s:%s\" 0x%zx\n",
+                          command_prefix, module_name, ModuleArchToString(arch),
+                          module_offset) >= static_cast<int>(kBufferSize)) {
+      Report("WARNING: Command buffer too small");
+      return nullptr;
+    }
+  }
+  return symbolizer_process_->SendCommand(buffer_);
+}
+
+SymbolizerProcess::SymbolizerProcess(const char *path, bool use_posix_spawn)
+    : path_(path),
+      input_fd_(kInvalidFd),
+      output_fd_(kInvalidFd),
+      times_restarted_(0),
+      failed_to_start_(false),
+      reported_invalid_path_(false),
+      use_posix_spawn_(use_posix_spawn) {
+  CHECK(path_);
+  CHECK_NE(path_[0], '\0');
+}
+
+static bool IsSameModule(const char* path) {
+  if (const char* ProcessName = GetProcessName()) {
+    if (const char* SymbolizerName = StripModuleName(path)) {
+      return !internal_strcmp(ProcessName, SymbolizerName);
+    }
+  }
+  return false;
+}
+
+const char *SymbolizerProcess::SendCommand(const char *command) {
+  if (failed_to_start_)
+    return nullptr;
+  if (IsSameModule(path_)) {
+    Report("WARNING: Symbolizer was blocked from starting itself!\n");
+    failed_to_start_ = true;
+    return nullptr;
+  }
+  for (; times_restarted_ < kMaxTimesRestarted; times_restarted_++) {
+    // Start or restart symbolizer if we failed to send command to it.
+    if (const char *res = SendCommandImpl(command))
+      return res;
+    Restart();
+  }
+  if (!failed_to_start_) {
+    Report("WARNING: Failed to use and restart external symbolizer!\n");
+    failed_to_start_ = true;
+  }
+  return 0;
+}
+
+const char *SymbolizerProcess::SendCommandImpl(const char *command) {
+  if (input_fd_ == kInvalidFd || output_fd_ == kInvalidFd)
+      return 0;
+  if (!WriteToSymbolizer(command, internal_strlen(command)))
+      return 0;
+  if (!ReadFromSymbolizer(buffer_, kBufferSize))
+      return 0;
+  return buffer_;
+}
+
+bool SymbolizerProcess::Restart() {
+  if (input_fd_ != kInvalidFd)
+    CloseFile(input_fd_);
+  if (output_fd_ != kInvalidFd)
+    CloseFile(output_fd_);
+  return StartSymbolizerSubprocess();
+}
+
+bool SymbolizerProcess::ReadFromSymbolizer(char *buffer, uptr max_length) {
+  if (max_length == 0)
+    return true;
+  uptr read_len = 0;
+  while (true) {
+    uptr just_read = 0;
+    bool success = ReadFromFile(input_fd_, buffer + read_len,
+                                max_length - read_len - 1, &just_read);
+    // We can't read 0 bytes, as we don't expect external symbolizer to close
+    // its stdout.
+    if (!success || just_read == 0) {
+      Report("WARNING: Can't read from symbolizer at fd %d\n", input_fd_);
+      return false;
+    }
+    read_len += just_read;
+    if (ReachedEndOfOutput(buffer, read_len))
+      break;
+    if (read_len + 1 == max_length) {
+      Report("WARNING: Symbolizer buffer too small\n");
+      read_len = 0;
+      break;
+    }
+  }
+  buffer[read_len] = '\0';
+  return true;
+}
+
+bool SymbolizerProcess::WriteToSymbolizer(const char *buffer, uptr length) {
+  if (length == 0)
+    return true;
+  uptr write_len = 0;
+  bool success = WriteToFile(output_fd_, buffer, length, &write_len);
+  if (!success || write_len != length) {
+    Report("WARNING: Can't write to symbolizer at fd %d\n", output_fd_);
+    return false;
+  }
+  return true;
+}
+
+#endif  // !SANITIZER_SYMBOLIZER_MARKUP
+
+}  // namespace __sanitizer