CheckedMalloc.cpp 3.6 KB

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  1. /*
  2. * Copyright (C) 2005, 2006, 2007, 2010 Apple Inc. All rights reserved.
  3. * (C) 2007 Graham Dennis (graham.dennis@gmail.com)
  4. * (C) 2007 Eric Seidel <eric@webkit.org>
  5. *
  6. * Redistribution and use in source and binary forms, with or without
  7. * modification, are permitted provided that the following conditions
  8. * are met:
  9. *
  10. * 1. Redistributions of source code must retain the above copyright
  11. * notice, this list of conditions and the following disclaimer.
  12. * 2. Redistributions in binary form must reproduce the above copyright
  13. * notice, this list of conditions and the following disclaimer in the
  14. * documentation and/or other materials provided with the distribution.
  15. * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  16. * its contributors may be used to endorse or promote products derived
  17. * from this software without specific prior written permission.
  18. *
  19. * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  20. * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  21. * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22. * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  23. * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24. * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  25. * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  26. * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27. * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  28. * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29. */
  30. #import "config.h"
  31. #import "CheckedMalloc.h"
  32. #import <mach/mach_init.h>
  33. #import <mach/mach_vm.h>
  34. #import <mach/vm_region.h>
  35. #import <malloc/malloc.h>
  36. #import <unistd.h>
  37. static void* (*savedMalloc)(malloc_zone_t*, size_t);
  38. static void* (*savedRealloc)(malloc_zone_t*, void*, size_t);
  39. static void* checkedMalloc(malloc_zone_t* zone, size_t size)
  40. {
  41. if (size >= 0x10000000)
  42. return 0;
  43. return savedMalloc(zone, size);
  44. }
  45. static void* checkedRealloc(malloc_zone_t* zone, void* ptr, size_t size)
  46. {
  47. if (size >= 0x10000000)
  48. return 0;
  49. return savedRealloc(zone, ptr, size);
  50. }
  51. #if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
  52. static vm_prot_t protectionOfRegion(mach_vm_address_t address)
  53. {
  54. mach_vm_size_t regionSize = 0;
  55. vm_region_basic_info_64 regionInfo;
  56. mach_msg_type_number_t regionInfoCount = VM_REGION_BASIC_INFO_COUNT_64;
  57. mach_port_t objectName;
  58. if (mach_vm_region(mach_task_self(), &address, &regionSize, VM_REGION_BASIC_INFO_64, (vm_region_info_t)&regionInfo, &regionInfoCount, &objectName))
  59. CRASH();
  60. return regionInfo.protection;
  61. }
  62. #endif
  63. void makeLargeMallocFailSilently()
  64. {
  65. malloc_zone_t* zone = malloc_default_zone();
  66. #if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
  67. mach_vm_address_t pageStart = reinterpret_cast<vm_address_t>(zone) & static_cast<vm_size_t>(~(getpagesize() - 1));
  68. vm_prot_t initialProtection = protectionOfRegion(pageStart);
  69. vm_size_t len = reinterpret_cast<vm_address_t>(zone) - pageStart + sizeof(malloc_zone_t);
  70. if (mach_vm_protect(mach_task_self(), pageStart, len, 0, initialProtection | VM_PROT_WRITE))
  71. CRASH();
  72. #endif
  73. savedMalloc = zone->malloc;
  74. savedRealloc = zone->realloc;
  75. zone->malloc = checkedMalloc;
  76. zone->realloc = checkedRealloc;
  77. #if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
  78. if (mach_vm_protect(mach_task_self(), pageStart, len, 0, initialProtection))
  79. CRASH();
  80. #endif
  81. }