lib/msan/msan.h

//===-- msan.h --------------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of MemorySanitizer.
//
// Private MSan header.
//===----------------------------------------------------------------------===//

#ifndef MSAN_H
#define MSAN_H

#include "sanitizer_common/sanitizer_flags.h"
#include "sanitizer_common/sanitizer_internal_defs.h"
#include "sanitizer_common/sanitizer_stacktrace.h"
#include "msan_interface_internal.h"
#include "msan_flags.h"
#include "ubsan/ubsan_platform.h"

#ifndef MSAN_REPLACE_OPERATORS_NEW_AND_DELETE
# define MSAN_REPLACE_OPERATORS_NEW_AND_DELETE 1
#endif

#ifndef MSAN_CONTAINS_UBSAN
# define MSAN_CONTAINS_UBSAN CAN_SANITIZE_UB
#endif

struct MappingDesc {
  uptr start;
  uptr end;
  enum Type {
    INVALID, APP, SHADOW, ORIGIN
  } type;
  const char *name;
};


#if SANITIZER_LINUX && defined(__mips64)

// Everything is above 0x00e000000000.
const MappingDesc kMemoryLayout[] = {
    {0x000000000000ULL, 0x00a000000000ULL, MappingDesc::INVALID, "invalid"},
    {0x00a000000000ULL, 0x00c000000000ULL, MappingDesc::SHADOW, "shadow"},
    {0x00c000000000ULL, 0x00e000000000ULL, MappingDesc::ORIGIN, "origin"},
    {0x00e000000000ULL, 0x010000000000ULL, MappingDesc::APP, "app"}};

#define MEM_TO_SHADOW(mem) (((uptr)(mem)) & ~0x4000000000ULL)
#define SHADOW_TO_ORIGIN(shadow) (((uptr)(shadow)) + 0x002000000000)

#elif SANITIZER_FREEBSD && SANITIZER_WORDSIZE == 64

// Low memory: main binary, MAP_32BIT mappings and modules
// High memory: heap, modules and main thread stack
const MappingDesc kMemoryLayout[] = {
    {0x000000000000ULL, 0x010000000000ULL, MappingDesc::APP, "low memory"},
    {0x010000000000ULL, 0x100000000000ULL, MappingDesc::INVALID, "invalid"},
    {0x100000000000ULL, 0x310000000000ULL, MappingDesc::SHADOW, "shadow"},
    {0x310000000000ULL, 0x380000000000ULL, MappingDesc::INVALID, "invalid"},
    {0x380000000000ULL, 0x590000000000ULL, MappingDesc::ORIGIN, "origin"},
    {0x590000000000ULL, 0x600000000000ULL, MappingDesc::INVALID, "invalid"},
    {0x600000000000ULL, 0x800000000000ULL, MappingDesc::APP, "high memory"}};

// Maps low and high app ranges to contiguous space with zero base:
//   Low:  0000 0000 0000 - 00ff ffff ffff  ->  2000 0000 0000 - 20ff ffff ffff
//   High: 6000 0000 0000 - 7fff ffff ffff  ->  0000 0000 0000 - 1fff ffff ffff
#define LINEARIZE_MEM(mem) \
  (((uptr)(mem) & ~0xc00000000000ULL) ^ 0x200000000000ULL)
#define MEM_TO_SHADOW(mem) (LINEARIZE_MEM((mem)) + 0x100000000000ULL)
#define SHADOW_TO_ORIGIN(shadow) (((uptr)(shadow)) + 0x280000000000)

#elif SANITIZER_LINUX && SANITIZER_WORDSIZE == 64

// Requries PIE binary and ASLR enabled.
// Main thread stack and DSOs at 0x7f0000000000 (sometimes 0x7e0000000000).
// Heap at 0x600000000000.
const MappingDesc kMemoryLayout[] = {
    {0x000000000000ULL, 0x200000000000ULL, MappingDesc::INVALID, "invalid"},
    {0x200000000000ULL, 0x400000000000ULL, MappingDesc::SHADOW, "shadow"},
    {0x400000000000ULL, 0x600000000000ULL, MappingDesc::ORIGIN, "origin"},
    {0x600000000000ULL, 0x800000000000ULL, MappingDesc::APP, "app"}};

#define MEM_TO_SHADOW(mem) (((uptr)(mem)) & ~0x400000000000ULL)
#define SHADOW_TO_ORIGIN(mem) (((uptr)(mem)) + 0x200000000000ULL)

#else
#error "Unsupported platform"
#endif

const uptr kMemoryLayoutSize = sizeof(kMemoryLayout) / sizeof(kMemoryLayout[0]);

#define MEM_TO_ORIGIN(mem) (SHADOW_TO_ORIGIN(MEM_TO_SHADOW((mem))))

#ifndef __clang__
__attribute__((optimize("unroll-loops")))
#endif
inline bool addr_is_type(uptr addr, MappingDesc::Type mapping_type) {
// It is critical for performance that this loop is unrolled (because then it is
// simplified into just a few constant comparisons).
#ifdef __clang__
#pragma unroll
#endif
  for (unsigned i = 0; i < kMemoryLayoutSize; ++i)
    if (kMemoryLayout[i].type == mapping_type &&
        addr >= kMemoryLayout[i].start && addr < kMemoryLayout[i].end)
      return true;
  return false;
}

#define MEM_IS_APP(mem) addr_is_type((uptr)(mem), MappingDesc::APP)
#define MEM_IS_SHADOW(mem) addr_is_type((uptr)(mem), MappingDesc::SHADOW)
#define MEM_IS_ORIGIN(mem) addr_is_type((uptr)(mem), MappingDesc::ORIGIN)

// These constants must be kept in sync with the ones in MemorySanitizer.cc.
const int kMsanParamTlsSize = 800;
const int kMsanRetvalTlsSize = 800;

namespace __msan {
extern int msan_inited;
extern bool msan_init_is_running;
extern int msan_report_count;

bool ProtectRange(uptr beg, uptr end);
bool InitShadow(bool init_origins);
char *GetProcSelfMaps();
void InitializeInterceptors();

void MsanAllocatorThreadFinish();
void *MsanCalloc(StackTrace *stack, uptr nmemb, uptr size);
void *MsanReallocate(StackTrace *stack, void *oldp, uptr size,
                     uptr alignment, bool zeroise);
void MsanDeallocate(StackTrace *stack, void *ptr);
void InstallTrapHandler();
void InstallAtExitHandler();

const char *GetStackOriginDescr(u32 id, uptr *pc);

void EnterSymbolizer();
void ExitSymbolizer();
bool IsInSymbolizer();

struct SymbolizerScope {
  SymbolizerScope() { EnterSymbolizer(); }
  ~SymbolizerScope() { ExitSymbolizer(); }
};

void MsanDie();
void PrintWarning(uptr pc, uptr bp);
void PrintWarningWithOrigin(uptr pc, uptr bp, u32 origin);

void GetStackTrace(BufferedStackTrace *stack, uptr max_s, uptr pc, uptr bp,
                   bool request_fast_unwind);

void ReportUMR(StackTrace *stack, u32 origin);
void ReportExpectedUMRNotFound(StackTrace *stack);
void ReportStats();
void ReportAtExitStatistics();
void DescribeMemoryRange(const void *x, uptr size);
void ReportUMRInsideAddressRange(const char *what, const void *start, uptr size,
                                 uptr offset);

// Unpoison first n function arguments.
void UnpoisonParam(uptr n);
void UnpoisonThreadLocalState();

// Returns a "chained" origin id, pointing to the given stack trace followed by
// the previous origin id.
u32 ChainOrigin(u32 id, StackTrace *stack);

const int STACK_TRACE_TAG_POISON = StackTrace::TAG_CUSTOM + 1;

#define GET_MALLOC_STACK_TRACE                                                 \
  BufferedStackTrace stack;                                                    \
  if (__msan_get_track_origins() && msan_inited)                               \
  GetStackTrace(&stack, common_flags()->malloc_context_size,                   \
                StackTrace::GetCurrentPc(), GET_CURRENT_FRAME(),               \
                common_flags()->fast_unwind_on_malloc)

#define GET_STORE_STACK_TRACE_PC_BP(pc, bp)                                    \
  BufferedStackTrace stack;                                                    \
  if (__msan_get_track_origins() > 1 && msan_inited)                           \
  GetStackTrace(&stack, flags()->store_context_size, pc, bp,                   \
                common_flags()->fast_unwind_on_malloc)

#define GET_FATAL_STACK_TRACE_PC_BP(pc, bp)                                    \
  BufferedStackTrace stack;                                                    \
  if (msan_inited)                                                             \
  GetStackTrace(&stack, kStackTraceMax, pc, bp,                                \
                common_flags()->fast_unwind_on_fatal)

#define GET_STORE_STACK_TRACE \
  GET_STORE_STACK_TRACE_PC_BP(StackTrace::GetCurrentPc(), GET_CURRENT_FRAME())

class ScopedThreadLocalStateBackup {
 public:
  ScopedThreadLocalStateBackup() { Backup(); }
  ~ScopedThreadLocalStateBackup() { Restore(); }
  void Backup();
  void Restore();
 private:
  u64 va_arg_overflow_size_tls;
};

extern void (*death_callback)(void);

void MsanTSDInit(void (*destructor)(void *tsd));
void *MsanTSDGet();
void MsanTSDSet(void *tsd);
void MsanTSDDtor(void *tsd);

}  // namespace __msan

#define MSAN_MALLOC_HOOK(ptr, size) \
  if (&__sanitizer_malloc_hook) __sanitizer_malloc_hook(ptr, size)
#define MSAN_FREE_HOOK(ptr) \
  if (&__sanitizer_free_hook) __sanitizer_free_hook(ptr)

#endif  // MSAN_H