1/* $OpenBSD: t_write.c,v 1.4 2021/12/13 16:56:48 deraadt Exp $ */ 2/* $NetBSD: t_write.c,v 1.7 2019/07/16 17:29:18 martin Exp $ */ 3 4/*- 5 * Copyright (c) 2001, 2008 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#include "macros.h" 31 32#include <sys/uio.h> 33#include <sys/mman.h> 34 35#include "atf-c.h" 36#include <errno.h> 37#include <fcntl.h> 38#include <signal.h> 39#include <limits.h> 40#include <stdio.h> 41#include <stdint.h> 42#include <string.h> 43#include <unistd.h> 44#include <paths.h> 45 46static void sighandler(int); 47 48static bool fail = false; 49static const char *path = "write"; 50 51static void 52sighandler(int signo __unused) 53{ 54 fail = false; 55} 56 57ATF_TC_WITH_CLEANUP(write_err); 58ATF_TC_HEAD(write_err, tc) 59{ 60 atf_tc_set_md_var(tc, "descr", "Checks errors from write(2)"); 61} 62 63ATF_TC_BODY(write_err, tc) 64{ 65 char rbuf[3] = { 'a', 'b', 'c' }; 66 char wbuf[3] = { 'x', 'y', 'z' }; 67 int fd; 68 69 errno = 0; 70 ATF_REQUIRE_ERRNO(EBADF, write(-1, wbuf, sizeof(wbuf)) == -1); 71 72 fd = open(path, O_RDWR | O_CREAT, 0600); 73 74 if (fd >= 0) { 75 76 errno = 0; 77 ATF_REQUIRE_ERRNO(0, write(fd, wbuf, 3) == 3); 78 79 errno = 0; 80 ATF_REQUIRE_ERRNO(EINVAL, write(fd, wbuf, SIZE_MAX) == -1); 81 82 errno = 0; 83 ATF_REQUIRE_ERRNO(EFAULT, write(fd, (void *)-1, 1) == -1); 84 85 /* 86 * Check that the above bogus write(2) 87 * calls did not corrupt the file. 88 */ 89 ATF_REQUIRE(lseek(fd, 0, SEEK_SET) == 0); 90 ATF_REQUIRE(read(fd, rbuf, 3) == 3); 91 ATF_REQUIRE(memcmp(rbuf, wbuf, 3) == 0); 92 93 (void)close(fd); 94 (void)unlink(path); 95 } 96} 97 98ATF_TC_CLEANUP(write_err, tc) 99{ 100 (void)unlink(path); 101} 102 103ATF_TC(write_pipe); 104ATF_TC_HEAD(write_pipe, tc) 105{ 106 atf_tc_set_md_var(tc, "descr", "Checks for EPIPE from write(2)"); 107} 108 109ATF_TC_BODY(write_pipe, tc) 110{ 111 int fds[2]; 112 113 ATF_REQUIRE(pipe(fds) == 0); 114 ATF_REQUIRE(signal(SIGPIPE, sighandler) == 0); 115 116 ATF_REQUIRE(write(fds[1], "x", 1) != -1); 117 ATF_REQUIRE(close(fds[0]) == 0); 118 119 errno = 0; 120 fail = true; 121 122 if (write(fds[1], "x", 1) != -1 || errno != EPIPE) 123 atf_tc_fail_nonfatal("expected EPIPE but write(2) succeeded"); 124 125 ATF_REQUIRE(close(fds[1]) == 0); 126 127 if (fail != false) 128 atf_tc_fail_nonfatal("SIGPIPE was not raised"); 129} 130 131ATF_TC_WITH_CLEANUP(write_pos); 132ATF_TC_HEAD(write_pos, tc) 133{ 134 atf_tc_set_md_var(tc, "descr", "Checks that write(2) " 135 "updates the file position"); 136} 137 138ATF_TC_BODY(write_pos, tc) 139{ 140 const size_t n = 123; 141 size_t i; 142 int fd; 143 144 fd = open(path, O_RDWR | O_CREAT, 0600); 145 ATF_REQUIRE(fd >= 0); 146 147 for (i = 0; i < n; i++) { 148 ATF_REQUIRE(write(fd, "x", 1) == 1); 149 ATF_REQUIRE(lseek(fd, 0, SEEK_CUR) == (off_t)(i + 1)); 150 } 151 152 ATF_REQUIRE(close(fd) == 0); 153 ATF_REQUIRE(unlink(path) == 0); 154} 155 156ATF_TC_CLEANUP(write_pos, tc) 157{ 158 (void)unlink(path); 159} 160 161ATF_TC_WITH_CLEANUP(write_ret); 162ATF_TC_HEAD(write_ret, tc) 163{ 164 atf_tc_set_md_var(tc, "descr", "Checks return values from write(2)"); 165} 166 167ATF_TC_BODY(write_ret, tc) 168{ 169 const size_t n = 99; 170 char buf[123]; 171 size_t i, j; 172 int fd; 173 174 fd = open(path, O_WRONLY | O_CREAT, 0600); 175 ATF_REQUIRE(fd >= 0); 176 177 (void)memset(buf, 'x', sizeof(buf)); 178 179 for (i = j = 0; i < n; i++) 180 j += write(fd, buf, sizeof(buf)); 181 182 if (j != n * 123) 183 atf_tc_fail("inconsistent return values from write(2)"); 184 185 (void)close(fd); 186 (void)unlink(path); 187} 188 189ATF_TC_CLEANUP(write_ret, tc) 190{ 191 (void)unlink(path); 192} 193 194ATF_TC(writev_iovmax); 195ATF_TC_HEAD(writev_iovmax, tc) 196{ 197 atf_tc_set_md_var(tc, "timeout", "10"); 198 atf_tc_set_md_var(tc, "descr", 199 "Checks that file descriptor is properly FILE_UNUSE()d " 200 "when iovcnt is greater than IOV_MAX"); 201} 202 203ATF_TC_BODY(writev_iovmax, tc) 204{ 205 ssize_t retval; 206 207 (void)printf("Calling writev(2, NULL, IOV_MAX + 1)...\n"); 208 209 errno = 0; 210 retval = writev(2, NULL, IOV_MAX + 1); 211 212 ATF_REQUIRE_EQ_MSG(retval, -1, "got: %zd", retval); 213 ATF_REQUIRE_EQ_MSG(errno, EINVAL, "got: %s", strerror(errno)); 214} 215 216ATF_TC(write_fault); 217 218ATF_TC_HEAD(write_fault, tc) 219{ 220 atf_tc_set_md_var(tc, "descr", 221 "Check that writing to non-permitted space returns EFAULT"); 222} 223 224#define SIZE 8192 225 226ATF_TC_BODY(write_fault, tc) 227{ 228 int fd[2]; 229 ATF_REQUIRE(pipe(fd) != -1); 230 // Can't use /dev/null cause it doesn't access the buffer. 231 232 void *map = mmap(NULL, SIZE, PROT_NONE, MAP_ANON | MAP_PRIVATE, -1, 0); 233 ATF_REQUIRE(map != MAP_FAILED); 234 235 ssize_t retval = write(fd[1], map, SIZE); 236 237 ATF_REQUIRE_EQ_MSG(retval, -1, "got: %zd", retval); 238 ATF_REQUIRE_EQ_MSG(errno, EFAULT, "got: %s", strerror(errno)); 239 240 munmap(map, SIZE); 241 close(fd[0]); 242 close(fd[1]); 243} 244 245ATF_TC(read_fault); 246 247ATF_TC_HEAD(read_fault, tc) 248{ 249 atf_tc_set_md_var(tc, "descr", 250 "Check that reading from non-permitted space returns EFAULT"); 251} 252 253ATF_TC_BODY(read_fault, tc) 254{ 255 int fd = open(_PATH_DEVZERO, O_RDONLY); 256 ATF_REQUIRE(fd != -1); 257 258 void *map = mmap(NULL, SIZE, PROT_NONE, MAP_ANON | MAP_PRIVATE, -1, 0); 259 ATF_REQUIRE(map != MAP_FAILED); 260 261 ssize_t retval = read(fd, map, SIZE); 262 263 ATF_REQUIRE_EQ_MSG(retval, -1, "got: %zd", retval); 264 ATF_REQUIRE_EQ_MSG(errno, EFAULT, "got: %s", strerror(errno)); 265 266 munmap(map, SIZE); 267 close(fd); 268} 269 270ATF_TP_ADD_TCS(tp) 271{ 272 273 ATF_TP_ADD_TC(tp, write_err); 274 ATF_TP_ADD_TC(tp, write_pipe); 275 ATF_TP_ADD_TC(tp, write_pos); 276 ATF_TP_ADD_TC(tp, write_ret); 277 ATF_TP_ADD_TC(tp, writev_iovmax); 278 ATF_TP_ADD_TC(tp, write_fault); 279 ATF_TP_ADD_TC(tp, read_fault); 280 281 return atf_no_error(); 282} 283