1 /* 2 * Copyright (c) 2015-2016 Dmitry V. Levin <ldv (at) altlinux.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include "tests.h" 29 #include <string.h> 30 #include <sys/mman.h> 31 32 void * 33 tail_alloc(const size_t size) 34 { 35 const size_t page_size = get_page_size(); 36 const size_t len = (size + page_size - 1) & -page_size; 37 const size_t alloc_size = len + 6 * page_size; 38 39 void *p = mmap(NULL, alloc_size, PROT_READ | PROT_WRITE, 40 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); 41 if (MAP_FAILED == p) 42 perror_msg_and_fail("mmap(%zu)", alloc_size); 43 44 void *start_work = p + 3 * page_size; 45 void *tail_guard = start_work + len; 46 47 if (munmap(p, page_size) || 48 munmap(p + 2 * page_size, page_size) || 49 munmap(tail_guard, page_size) || 50 munmap(tail_guard + 2 * page_size, page_size)) 51 perror_msg_and_fail("munmap"); 52 53 memset(start_work, 0xff, len); 54 return tail_guard - size; 55 } 56 57 void * 58 tail_memdup(const void *p, const size_t size) 59 { 60 void *dest = tail_alloc(size); 61 memcpy(dest, p, size); 62 return dest; 63 } 64
