1 files changed, 348 insertions, 0 deletions

diff --git a/lib/sanitizer_common/sanitizer_linux.cc b/lib/sanitizer_common/sanitizer_linux.cc
new file mode 100644
index 0000000..70e2eb3
--- /dev/null
+++ b/lib/sanitizer_common/sanitizer_linux.cc
@@ -0,0 +1,348 @@
+//===-- sanitizer_linux.cc ------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is shared between AddressSanitizer and ThreadSanitizer
+// run-time libraries and implements linux-specific functions from
+// sanitizer_libc.h.
+//===----------------------------------------------------------------------===//
+#ifdef __linux__
+
+#include "sanitizer_common.h"
+#include "sanitizer_internal_defs.h"
+#include "sanitizer_libc.h"
+#include "sanitizer_placement_new.h"
+#include "sanitizer_procmaps.h"
+#include "sanitizer_symbolizer.h"
+
+#include <elf.h>
+#include <fcntl.h>
+#include <link.h>
+#include <pthread.h>
+#include <sched.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+namespace __sanitizer {
+
+// --------------- sanitizer_libc.h
+void *internal_mmap(void *addr, uptr length, int prot, int flags,
+                    int fd, u64 offset) {
+#if __WORDSIZE == 64
+  return (void *)syscall(__NR_mmap, addr, length, prot, flags, fd, offset);
+#else
+  return (void *)syscall(__NR_mmap2, addr, length, prot, flags, fd, offset);
+#endif
+}
+
+int internal_munmap(void *addr, uptr length) {
+  return syscall(__NR_munmap, addr, length);
+}
+
+int internal_close(fd_t fd) {
+  return syscall(__NR_close, fd);
+}
+
+fd_t internal_open(const char *filename, bool write) {
+  return syscall(__NR_open, filename,
+      write ? O_WRONLY | O_CREAT /*| O_CLOEXEC*/ : O_RDONLY, 0660);
+}
+
+uptr internal_read(fd_t fd, void *buf, uptr count) {
+  return (uptr)syscall(__NR_read, fd, buf, count);
+}
+
+uptr internal_write(fd_t fd, const void *buf, uptr count) {
+  return (uptr)syscall(__NR_write, fd, buf, count);
+}
+
+uptr internal_filesize(fd_t fd) {
+#if __WORDSIZE == 64
+  struct stat st;
+  if (syscall(__NR_fstat, fd, &st))
+    return -1;
+#else
+  struct stat64 st;
+  if (syscall(__NR_fstat64, fd, &st))
+    return -1;
+#endif
+  return (uptr)st.st_size;
+}
+
+int internal_dup2(int oldfd, int newfd) {
+  return syscall(__NR_dup2, oldfd, newfd);
+}
+
+int internal_sched_yield() {
+  return syscall(__NR_sched_yield);
+}
+
+// ----------------- sanitizer_common.h
+void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
+                                uptr *stack_bottom) {
+  static const uptr kMaxThreadStackSize = 256 * (1 << 20);  // 256M
+  CHECK(stack_top);
+  CHECK(stack_bottom);
+  if (at_initialization) {
+    // This is the main thread. Libpthread may not be initialized yet.
+    struct rlimit rl;
+    CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
+
+    // Find the mapping that contains a stack variable.
+    ProcessMaps proc_maps;
+    uptr start, end, offset;
+    uptr prev_end = 0;
+    while (proc_maps.Next(&start, &end, &offset, 0, 0)) {
+      if ((uptr)&rl < end)
+        break;
+      prev_end = end;
+    }
+    CHECK((uptr)&rl >= start && (uptr)&rl < end);
+
+    // Get stacksize from rlimit, but clip it so that it does not overlap
+    // with other mappings.
+    uptr stacksize = rl.rlim_cur;
+    if (stacksize > end - prev_end)
+      stacksize = end - prev_end;
+    // When running with unlimited stack size, we still want to set some limit.
+    // The unlimited stack size is caused by 'ulimit -s unlimited'.
+    // Also, for some reason, GNU make spawns subprocesses with unlimited stack.
+    if (stacksize > kMaxThreadStackSize)
+      stacksize = kMaxThreadStackSize;
+    *stack_top = end;
+    *stack_bottom = end - stacksize;
+    return;
+  }
+  pthread_attr_t attr;
+  CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
+  uptr stacksize = 0;
+  void *stackaddr = 0;
+  pthread_attr_getstack(&attr, &stackaddr, (size_t*)&stacksize);
+  pthread_attr_destroy(&attr);
+
+  *stack_top = (uptr)stackaddr + stacksize;
+  *stack_bottom = (uptr)stackaddr;
+  CHECK(stacksize < kMaxThreadStackSize);  // Sanity check.
+}
+
+// Like getenv, but reads env directly from /proc and does not use libc.
+// This function should be called first inside __asan_init.
+const char *GetEnv(const char *name) {
+  static char *environ;
+  static uptr len;
+  static bool inited;
+  if (!inited) {
+    inited = true;
+    uptr environ_size;
+    len = ReadFileToBuffer("/proc/self/environ",
+                           &environ, &environ_size, 1 << 26);
+  }
+  if (!environ || len == 0) return 0;
+  uptr namelen = internal_strlen(name);
+  const char *p = environ;
+  while (*p != '\0') {  // will happen at the \0\0 that terminates the buffer
+    // proc file has the format NAME=value\0NAME=value\0NAME=value\0...
+    const char* endp =
+        (char*)internal_memchr(p, '\0', len - (p - environ));
+    if (endp == 0)  // this entry isn't NUL terminated
+      return 0;
+    else if (!internal_memcmp(p, name, namelen) && p[namelen] == '=')  // Match.
+      return p + namelen + 1;  // point after =
+    p = endp + 1;
+  }
+  return 0;  // Not found.
+}
+
+// ------------------ sanitizer_symbolizer.h
+typedef ElfW(Ehdr) Elf_Ehdr;
+typedef ElfW(Shdr) Elf_Shdr;
+typedef ElfW(Phdr) Elf_Phdr;
+
+bool FindDWARFSection(uptr object_file_addr, const char *section_name,
+                      DWARFSection *section) {
+  Elf_Ehdr *exe = (Elf_Ehdr*)object_file_addr;
+  Elf_Shdr *sections = (Elf_Shdr*)(object_file_addr + exe->e_shoff);
+  uptr section_names = object_file_addr +
+                       sections[exe->e_shstrndx].sh_offset;
+  for (int i = 0; i < exe->e_shnum; i++) {
+    Elf_Shdr *current_section = &sections[i];
+    const char *current_name = (const char*)section_names +
+                               current_section->sh_name;
+    if (IsFullNameOfDWARFSection(current_name, section_name)) {
+      section->data = (const char*)object_file_addr +
+                      current_section->sh_offset;
+      section->size = current_section->sh_size;
+      return true;
+    }
+  }
+  return false;
+}
+
+#ifdef ANDROID
+uptr GetListOfModules(ModuleDIContext *modules, uptr max_modules) {
+  UNIMPLEMENTED();
+}
+#else  // ANDROID
+struct DlIteratePhdrData {
+  ModuleDIContext *modules;
+  uptr current_n;
+  uptr max_n;
+};
+
+static const uptr kMaxPathLength = 512;
+
+static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
+  DlIteratePhdrData *data = (DlIteratePhdrData*)arg;
+  if (data->current_n == data->max_n)
+    return 0;
+  char *module_name = 0;
+  if (data->current_n == 0) {
+    // First module is the binary itself.
+    module_name = (char*)InternalAlloc(kMaxPathLength);
+    uptr module_name_len = readlink("/proc/self/exe",
+                                    module_name, kMaxPathLength);
+    CHECK_NE(module_name_len, (uptr)-1);
+    CHECK_LT(module_name_len, kMaxPathLength);
+    module_name[module_name_len] = '\0';
+  } else if (info->dlpi_name) {
+    module_name = internal_strdup(info->dlpi_name);
+  }
+  if (module_name == 0 || module_name[0] == '\0')
+    return 0;
+  void *mem = &data->modules[data->current_n];
+  ModuleDIContext *cur_module = new(mem) ModuleDIContext(module_name,
+                                                         info->dlpi_addr);
+  data->current_n++;
+  for (int i = 0; i < info->dlpi_phnum; i++) {
+    const Elf_Phdr *phdr = &info->dlpi_phdr[i];
+    if (phdr->p_type == PT_LOAD) {
+      uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
+      uptr cur_end = cur_beg + phdr->p_memsz;
+      cur_module->addAddressRange(cur_beg, cur_end);
+    }
+  }
+  InternalFree(module_name);
+  return 0;
+}
+
+uptr GetListOfModules(ModuleDIContext *modules, uptr max_modules) {
+  CHECK(modules);
+  DlIteratePhdrData data = {modules, 0, max_modules};
+  dl_iterate_phdr(dl_iterate_phdr_cb, &data);
+  return data.current_n;
+}
+#endif  // ANDROID
+
+// ----------------- sanitizer_procmaps.h
+ProcessMaps::ProcessMaps() {
+  proc_self_maps_buff_len_ =
+      ReadFileToBuffer("/proc/self/maps", &proc_self_maps_buff_,
+                       &proc_self_maps_buff_mmaped_size_, 1 << 26);
+  CHECK_GT(proc_self_maps_buff_len_, 0);
+  // internal_write(2, proc_self_maps_buff_, proc_self_maps_buff_len_);
+  Reset();
+}
+
+ProcessMaps::~ProcessMaps() {
+  UnmapOrDie(proc_self_maps_buff_, proc_self_maps_buff_mmaped_size_);
+}
+
+void ProcessMaps::Reset() {
+  current_ = proc_self_maps_buff_;
+}
+
+// Parse a hex value in str and update str.
+static uptr ParseHex(char **str) {
+  uptr x = 0;
+  char *s;
+  for (s = *str; ; s++) {
+    char c = *s;
+    uptr v = 0;
+    if (c >= '0' && c <= '9')
+      v = c - '0';
+    else if (c >= 'a' && c <= 'f')
+      v = c - 'a' + 10;
+    else if (c >= 'A' && c <= 'F')
+      v = c - 'A' + 10;
+    else
+      break;
+    x = x * 16 + v;
+  }
+  *str = s;
+  return x;
+}
+
+static bool IsOnOf(char c, char c1, char c2) {
+  return c == c1 || c == c2;
+}
+
+static bool IsDecimal(char c) {
+  return c >= '0' && c <= '9';
+}
+
+bool ProcessMaps::Next(uptr *start, uptr *end, uptr *offset,
+                       char filename[], uptr filename_size) {
+  char *last = proc_self_maps_buff_ + proc_self_maps_buff_len_;
+  if (current_ >= last) return false;
+  uptr dummy;
+  if (!start) start = &dummy;
+  if (!end) end = &dummy;
+  if (!offset) offset = &dummy;
+  char *next_line = (char*)internal_memchr(current_, '\n', last - current_);
+  if (next_line == 0)
+    next_line = last;
+  // Example: 08048000-08056000 r-xp 00000000 03:0c 64593   /foo/bar
+  *start = ParseHex(&current_);
+  CHECK_EQ(*current_++, '-');
+  *end = ParseHex(&current_);
+  CHECK_EQ(*current_++, ' ');
+  CHECK(IsOnOf(*current_++, '-', 'r'));
+  CHECK(IsOnOf(*current_++, '-', 'w'));
+  CHECK(IsOnOf(*current_++, '-', 'x'));
+  CHECK(IsOnOf(*current_++, 's', 'p'));
+  CHECK_EQ(*current_++, ' ');
+  *offset = ParseHex(&current_);
+  CHECK_EQ(*current_++, ' ');
+  ParseHex(&current_);
+  CHECK_EQ(*current_++, ':');
+  ParseHex(&current_);
+  CHECK_EQ(*current_++, ' ');
+  while (IsDecimal(*current_))
+    current_++;
+  CHECK_EQ(*current_++, ' ');
+  // Skip spaces.
+  while (current_ < next_line && *current_ == ' ')
+    current_++;
+  // Fill in the filename.
+  uptr i = 0;
+  while (current_ < next_line) {
+    if (filename && i < filename_size - 1)
+      filename[i++] = *current_;
+    current_++;
+  }
+  if (filename && i < filename_size)
+    filename[i] = 0;
+  current_ = next_line + 1;
+  return true;
+}
+
+// Gets the object name and the offset by walking ProcessMaps.
+bool ProcessMaps::GetObjectNameAndOffset(uptr addr, uptr *offset,
+                                         char filename[],
+                                         uptr filename_size) {
+  return IterateForObjectNameAndOffset(addr, offset, filename, filename_size);
+}
+
+}  // namespace __sanitizer
+
+#endif  // __linux__