libsanitizer/sanitizer_common/sanitizer_linux.h

   1 //===-- sanitizer_linux.h ---------------------------------------*- C++ -*-===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // Linux-specific syscall wrappers and classes.
   9 //
  10 //===----------------------------------------------------------------------===//
  11 #ifndef SANITIZER_LINUX_H
  12 #define SANITIZER_LINUX_H
  13
  14 #include "sanitizer_platform.h"
  15 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
  16 #include "sanitizer_common.h"
  17 #include "sanitizer_internal_defs.h"
  18 #include "sanitizer_platform_limits_netbsd.h"
  19 #include "sanitizer_platform_limits_posix.h"
  20 #include "sanitizer_posix.h"
  21
  22 struct link_map;  // Opaque type returned by dlopen().
  23
  24 namespace __sanitizer {
  25 // Dirent structure for getdents(). Note that this structure is different from
  26 // the one in <dirent.h>, which is used by readdir().
  27 struct linux_dirent;
  28
  29 struct ProcSelfMapsBuff {
  30   char *data;
  31   uptr mmaped_size;
  32   uptr len;
  33 };
  34
  35 struct MemoryMappingLayoutData {
  36   ProcSelfMapsBuff proc_self_maps;
  37   const char *current;
  38 };
  39
  40 void ReadProcMaps(ProcSelfMapsBuff *proc_maps);
  41
  42 // Syscall wrappers.
  43 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
  44 uptr internal_sigaltstack(const void* ss, void* oss);
  45 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
  46     __sanitizer_sigset_t *oldset);
  47
  48 // Linux-only syscalls.
  49 #if SANITIZER_LINUX
  50 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5);
  51 // Used only by sanitizer_stoptheworld. Signal handlers that are actually used
  52 // (like the process-wide error reporting SEGV handler) must use
  53 // internal_sigaction instead.
  54 int internal_sigaction_norestorer(int signum, const void *act, void *oldact);
  55 #if (defined(__x86_64__) || SANITIZER_MIPS64) && !SANITIZER_GO
  56 // Uses a raw system call to avoid interceptors.
  57 int internal_sigaction_syscall(int signum, const void *act, void *oldact);
  58 #endif
  59 void internal_sigdelset(__sanitizer_sigset_t *set, int signum);
  60 #if defined(__x86_64__) || defined(__mips__) || defined(__aarch64__) \
  61   || defined(__powerpc64__) || defined(__s390__) || defined(__i386__) \
  62   || defined(__arm__)
  63 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
  64                     int *parent_tidptr, void *newtls, int *child_tidptr);
  65 #endif
  66 #endif  // SANITIZER_LINUX
  67
  68 // This class reads thread IDs from /proc/<pid>/task using only syscalls.
  69 class ThreadLister {
  70  public:
  71   explicit ThreadLister(int pid);
  72   ~ThreadLister();
  73   // GetNextTID returns -1 if the list of threads is exhausted, or if there has
  74   // been an error.
  75   int GetNextTID();
  76   void Reset();
  77   bool error();
  78
  79  private:
  80   bool GetDirectoryEntries();
  81
  82   int pid_;
  83   int descriptor_;
  84   InternalScopedBuffer<char> buffer_;
  85   bool error_;
  86   struct linux_dirent* entry_;
  87   int bytes_read_;
  88 };
  89
  90 // Exposed for testing.
  91 uptr ThreadDescriptorSize();
  92 uptr ThreadSelf();
  93 uptr ThreadSelfOffset();
  94
  95 // Matches a library's file name against a base name (stripping path and version
  96 // information).
  97 bool LibraryNameIs(const char *full_name, const char *base_name);
  98
  99 // Call cb for each region mapped by map.
 100 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr));
 101
 102 #if SANITIZER_ANDROID
 103
 104 #if defined(__aarch64__)
 105 # define __get_tls() \
 106     ({ void** __v; __asm__("mrs %0, tpidr_el0" : "=r"(__v)); __v; })
 107 #elif defined(__arm__)
 108 # define __get_tls() \
 109     ({ void** __v; __asm__("mrc p15, 0, %0, c13, c0, 3" : "=r"(__v)); __v; })
 110 #elif defined(__mips__)
 111 // On mips32r1, this goes via a kernel illegal instruction trap that's
 112 // optimized for v1.
 113 # define __get_tls() \
 114     ({ register void** __v asm("v1"); \
 115        __asm__(".set    push\n" \
 116                ".set    mips32r2\n" \
 117                "rdhwr   %0,$29\n" \
 118                ".set    pop\n" : "=r"(__v)); \
 119        __v; })
 120 #elif defined(__i386__)
 121 # define __get_tls() \
 122     ({ void** __v; __asm__("movl %%gs:0, %0" : "=r"(__v)); __v; })
 123 #elif defined(__x86_64__)
 124 # define __get_tls() \
 125     ({ void** __v; __asm__("mov %%fs:0, %0" : "=r"(__v)); __v; })
 126 #else
 127 #error "Unsupported architecture."
 128 #endif
 129
 130 // The Android Bionic team has allocated a TLS slot for TSan starting with N,
 131 // given that Android currently doesn't support ELF TLS. It is used to store
 132 // Sanitizers thread specific data.
 133 static const int TLS_SLOT_TSAN = 8;
 134
 135 ALWAYS_INLINE uptr *get_android_tls_ptr() {
 136   return reinterpret_cast<uptr *>(&__get_tls()[TLS_SLOT_TSAN]);
 137 }
 138
 139 #endif  // SANITIZER_ANDROID
 140
 141 }  // namespace __sanitizer
 142
 143 #endif  // SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD
 144 #endif  // SANITIZER_LINUX_H