Home | History | Annotate | Download | only in mac
      1 /*
      2  * Copyright (C) 2005, 2006, 2007, 2010 Apple Inc. All rights reserved.
      3  *           (C) 2007 Graham Dennis (graham.dennis (at) gmail.com)
      4  *           (C) 2007 Eric Seidel <eric (at) 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 
     31 #import "config.h"
     32 #import "CheckedMalloc.h"
     33 
     34 #import <mach/mach_init.h>
     35 #import <mach/mach_vm.h>
     36 #import <mach/vm_region.h>
     37 #import <malloc/malloc.h>
     38 
     39 static void* (*savedMalloc)(malloc_zone_t*, size_t);
     40 static void* (*savedRealloc)(malloc_zone_t*, void*, size_t);
     41 
     42 static void* checkedMalloc(malloc_zone_t* zone, size_t size)
     43 {
     44     if (size >= 0x10000000)
     45         return 0;
     46     return savedMalloc(zone, size);
     47 }
     48 
     49 static void* checkedRealloc(malloc_zone_t* zone, void* ptr, size_t size)
     50 {
     51     if (size >= 0x10000000)
     52         return 0;
     53     return savedRealloc(zone, ptr, size);
     54 }
     55 
     56 #if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD) && !defined(BUILDING_ON_SNOW_LEOPARD)
     57 static vm_prot_t protectionOfRegion(mach_vm_address_t address)
     58 {
     59     mach_vm_size_t regionSize = 0;
     60     vm_region_basic_info_64 regionInfo;
     61     mach_msg_type_number_t regionInfoCount = VM_REGION_BASIC_INFO_COUNT_64;
     62     mach_port_t objectName;
     63     if (mach_vm_region(mach_task_self(), &address, &regionSize, VM_REGION_BASIC_INFO_64, (vm_region_info_t)&regionInfo, &regionInfoCount, &objectName))
     64         CRASH();
     65     return regionInfo.protection;
     66 }
     67 #endif
     68 
     69 void makeLargeMallocFailSilently()
     70 {
     71     malloc_zone_t* zone = malloc_default_zone();
     72 
     73 #if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD) && !defined(BUILDING_ON_SNOW_LEOPARD)
     74     mach_vm_address_t pageStart = reinterpret_cast<vm_address_t>(zone) & static_cast<vm_size_t>(~(getpagesize() - 1));
     75     vm_prot_t initialProtection = protectionOfRegion(pageStart);
     76 
     77     vm_size_t len = reinterpret_cast<vm_address_t>(zone) - pageStart + sizeof(malloc_zone_t);
     78     if (mach_vm_protect(mach_task_self(), pageStart, len, 0, initialProtection | VM_PROT_WRITE))
     79         CRASH();
     80 #endif
     81 
     82     savedMalloc = zone->malloc;
     83     savedRealloc = zone->realloc;
     84     zone->malloc = checkedMalloc;
     85     zone->realloc = checkedRealloc;
     86 
     87 #if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD) && !defined(BUILDING_ON_SNOW_LEOPARD)
     88     if (mach_vm_protect(mach_task_self(), pageStart, len, 0, initialProtection))
     89         CRASH();
     90 #endif
     91 }
     92