1 /* 2 * Check decoding of msg_name* fields of struct msghdr array argument 3 * of sendmmsg and recvmmsg syscalls. 4 * 5 * Copyright (c) 2016 Dmitry V. Levin <ldv (at) altlinux.org> 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 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * 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 #include "tests.h" 32 33 #include <errno.h> 34 #include <limits.h> 35 #include <stddef.h> 36 #include <stdio.h> 37 #include <string.h> 38 #include <unistd.h> 39 #include <sys/un.h> 40 41 #include "msghdr.h" 42 43 #define DEFAULT_STRLEN 32 44 45 #define IOV_MAX1 (IOV_MAX + 1) 46 47 #ifndef TEST_NAME 48 # define TEST_NAME "mmsg_name" 49 #endif 50 51 static void 52 print_msghdr(const struct msghdr *const msg, const int user_msg_namelen) 53 { 54 const struct sockaddr_un *const un = msg->msg_name; 55 const int offsetof_sun_path = offsetof(struct sockaddr_un, sun_path); 56 57 printf("{msg_name="); 58 if (!un) 59 printf("NULL"); 60 else if (user_msg_namelen < offsetof_sun_path) { 61 printf("%p", un); 62 } else { 63 printf("{sa_family=AF_UNIX"); 64 if (user_msg_namelen > offsetof_sun_path) { 65 int len = user_msg_namelen < (int) msg->msg_namelen ? 66 user_msg_namelen : (int) msg->msg_namelen; 67 len -= offsetof_sun_path; 68 if (len > (int) sizeof(un->sun_path)) 69 len = sizeof(un->sun_path); 70 printf(", sun_path=\"%.*s\"", len, un->sun_path); 71 } 72 printf("}"); 73 } 74 printf(", msg_namelen="); 75 if (user_msg_namelen != (int) msg->msg_namelen) { 76 printf("%d->", user_msg_namelen); 77 } 78 printf("%d, msg_iov=[{iov_base=\"%c\", iov_len=1}]" 79 ", msg_iovlen=1, msg_controllen=0, msg_flags=0}", 80 (int) msg->msg_namelen, * (char *) msg->msg_iov[0].iov_base); 81 } 82 83 static void 84 test_mmsg_name(const int send_fd, const int recv_fd) 85 { 86 struct sockaddr_un *const send_addr = 87 tail_alloc(sizeof(*send_addr) * IOV_MAX1); 88 char *const send_buf = tail_alloc(sizeof(*send_buf) * IOV_MAX1); 89 struct iovec *const send_iov = tail_alloc(sizeof(*send_iov) * IOV_MAX1); 90 struct mmsghdr *const send_mh = tail_alloc(sizeof(*send_mh) * IOV_MAX1); 91 92 int i, rc; 93 94 for (i = 0; i < IOV_MAX1; ++i) { 95 int sun_len = i + 1 > (int) sizeof(send_addr[i].sun_path) 96 ? (int) sizeof(send_addr[i].sun_path) 97 : i + 1; 98 99 send_addr[i].sun_family = AF_UNIX; 100 memset(send_addr[i].sun_path, 'a' + i % 26, sun_len); 101 102 send_buf[i] = '0' + i % 10; 103 104 send_iov[i].iov_base = &send_buf[i]; 105 send_iov[i].iov_len = sizeof(*send_buf); 106 107 send_mh[i].msg_hdr.msg_iov = &send_iov[i]; 108 send_mh[i].msg_hdr.msg_iovlen = 1; 109 send_mh[i].msg_hdr.msg_name = &send_addr[i]; 110 send_mh[i].msg_hdr.msg_namelen = i + 1; 111 send_mh[i].msg_hdr.msg_control = 0; 112 send_mh[i].msg_hdr.msg_controllen = 0; 113 send_mh[i].msg_hdr.msg_flags = 0; 114 } 115 116 rc = send_mmsg(send_fd, send_mh, IOV_MAX1, MSG_DONTWAIT); 117 int saved_errno = errno; 118 119 printf("sendmmsg(%d, [", send_fd); 120 for (i = 0; i < IOV_MAX1; ++i) { 121 if (i) 122 printf(", "); 123 if (i >= IOV_MAX 124 # if !VERBOSE 125 || i >= DEFAULT_STRLEN 126 # endif 127 ) { 128 printf("..."); 129 break; 130 } 131 printf("{msg_hdr="); 132 print_msghdr(&send_mh[i].msg_hdr, i + 1); 133 printf("}"); 134 } 135 errno = saved_errno; 136 printf("], %u, MSG_DONTWAIT) = %d %s (%m)\n", 137 IOV_MAX1, rc, errno2name()); 138 139 for (i = 0; i < IOV_MAX1; ++i) { 140 send_mh[i].msg_hdr.msg_name = 0; 141 send_mh[i].msg_hdr.msg_namelen = 0; 142 } 143 144 /* 145 * When recvmmsg is called with a valid descriptor 146 * but inaccessible memory, it causes segfaults on some architectures. 147 * As in these cases we test decoding of failed recvmmsg calls, 148 * it's ok to fail recvmmsg with any reason as long as 149 * it doesn't read that inaccessible memory. 150 */ 151 rc = send_mmsg(-1, &send_mh[IOV_MAX], 2, MSG_DONTWAIT); 152 saved_errno = errno; 153 printf("sendmmsg(-1, [{msg_hdr="); 154 print_msghdr(&send_mh[IOV_MAX].msg_hdr, 0); 155 errno = saved_errno; 156 printf("}, %p], %u, MSG_DONTWAIT) = %d %s (%m)\n", 157 &send_mh[IOV_MAX1], 2, rc, errno2name()); 158 159 rc = send_mmsg(send_fd, send_mh, IOV_MAX1, MSG_DONTWAIT); 160 if (rc < 0) 161 perror_msg_and_skip("sendmmsg"); 162 163 printf("sendmmsg(%d, [", send_fd); 164 for (i = 0; i < IOV_MAX1; ++i) { 165 if (i) 166 printf(", "); 167 if (i >= IOV_MAX 168 #if !VERBOSE 169 || i >= DEFAULT_STRLEN 170 #endif 171 ) { 172 printf("..."); 173 break; 174 } 175 printf("{msg_hdr="); 176 print_msghdr(&send_mh[i].msg_hdr, 0); 177 printf("%s}", i < rc ? ", msg_len=1" : ""); 178 } 179 printf("], %u, MSG_DONTWAIT) = %d\n", IOV_MAX1, rc); 180 181 struct sockaddr_un *const recv_addr = 182 tail_alloc(sizeof(*recv_addr) * IOV_MAX1); 183 char *const recv_buf = tail_alloc(sizeof(*recv_buf) * IOV_MAX1); 184 struct iovec *const recv_iov = tail_alloc(sizeof(*recv_iov) * IOV_MAX1); 185 struct mmsghdr *const recv_mh = tail_alloc(sizeof(*recv_mh) * IOV_MAX1); 186 187 for (i = 0; i < IOV_MAX1; ++i) { 188 recv_iov[i].iov_base = &recv_buf[i]; 189 recv_iov[i].iov_len = sizeof(*recv_buf); 190 191 recv_mh[i].msg_hdr.msg_name = &recv_addr[i]; 192 recv_mh[i].msg_hdr.msg_namelen = i; 193 recv_mh[i].msg_hdr.msg_iov = &recv_iov[i]; 194 recv_mh[i].msg_hdr.msg_iovlen = 1; 195 recv_mh[i].msg_hdr.msg_control = 0; 196 recv_mh[i].msg_hdr.msg_controllen = 0; 197 recv_mh[i].msg_hdr.msg_flags = 0; 198 } 199 200 rc = recv_mmsg(recv_fd, recv_mh, IOV_MAX1, MSG_DONTWAIT, 0); 201 if (rc < 0) 202 perror_msg_and_skip("recvmmsg"); 203 204 printf("recvmmsg(%d, [", recv_fd); 205 for (i = 0; i < rc; ++i) { 206 if (i) 207 printf(", "); 208 #if !VERBOSE 209 if (i >= DEFAULT_STRLEN) { 210 printf("..."); 211 break; 212 } 213 #endif 214 printf("{msg_hdr="); 215 print_msghdr(&recv_mh[i].msg_hdr, i); 216 printf(", msg_len=1}"); 217 } 218 printf("], %u, MSG_DONTWAIT, NULL) = %d\n", IOV_MAX1, rc); 219 } 220 221 int 222 main(void) 223 { 224 int fds[2]; 225 if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds)) 226 perror_msg_and_skip("socketpair"); 227 228 const struct sockaddr_un un = { 229 .sun_family = AF_UNIX, 230 .sun_path = TEST_NAME "-recvmmsg.test.send.socket" 231 }; 232 233 (void) unlink(un.sun_path); 234 if (bind(fds[1], (const void *) &un, sizeof(un))) 235 perror_msg_and_skip("bind"); 236 (void) unlink(un.sun_path); 237 238 test_mmsg_name(fds[1], fds[0]); 239 240 puts("+++ exited with 0 +++"); 241 return 0; 242 } 243
