1 /* $OpenBSD: mmap0.c,v 1.1 2011/10/07 19:43:07 ariane Exp $ */ 2 /* 3 * Copyright (c) 2011 Ariane van der Steldt <ariane@stack.nl> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/types.h> 19 #include <sys/mman.h> 20 #include <err.h> 21 #include <fcntl.h> 22 #include <sysexits.h> 23 #include <errno.h> 24 25 26 /* 27 * Mmap allocations with len=0 must fail with EINVAL. 28 * 29 * Posix says so and the vmmap implementation may not deal well with them 30 * either. 31 */ 32 int 33 main() 34 { 35 void *ptr; 36 int errors = 0; 37 int fd; 38 39 fd = open("/dev/zero", O_RDWR, 0); 40 if (fd == -1) 41 err(EX_OSERR, "open"); 42 43 ptr = mmap(NULL, 0, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); 44 if (ptr != MAP_FAILED) { 45 warn("mmap(len=0, MAP_ANON) return %p, expected MAP_FAILED", 46 ptr); 47 errors += 1; 48 } else if (errno != EINVAL) { 49 warn("mmap(len=0, MAP_ANON) errno %d, expected %d", 50 errno, EINVAL); 51 } 52 53 ptr = mmap(NULL, 0, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 54 if (ptr != MAP_FAILED) { 55 warn("mmap(len=0, fd=\"/dev/zero\") returned %p, " 56 "expected MAP_FAILED", ptr); 57 errors += 1; 58 } else if (errno != EINVAL) { 59 warn("mmap(len=0, fd=\"/dev/zero\") errno %d, expected %d", 60 errno, EINVAL); 61 } 62 63 return errors; 64 } 65