1 /* $NetBSD: procfs_vfsops.c,v 1.95 2016/11/03 03:53:32 pgoyette Exp $ */ 2 3 /* 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)procfs_vfsops.c 8.7 (Berkeley) 5/10/95 35 */ 36 37 /* 38 * Copyright (c) 1993 Jan-Simon Pendry 39 * 40 * This code is derived from software contributed to Berkeley by 41 * Jan-Simon Pendry. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by the University of 54 * California, Berkeley and its contributors. 55 * 4. Neither the name of the University nor the names of its contributors 56 * may be used to endorse or promote products derived from this software 57 * without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * @(#)procfs_vfsops.c 8.7 (Berkeley) 5/10/95 72 */ 73 74 /* 75 * procfs VFS interface 76 */ 77 78 #include <sys/cdefs.h> 79 __KERNEL_RCSID(0, "$NetBSD: procfs_vfsops.c,v 1.95 2016/11/03 03:53:32 pgoyette Exp $"); 80 81 #if defined(_KERNEL_OPT) 82 #include "opt_compat_netbsd.h" 83 #endif 84 85 #include <sys/param.h> 86 #include <sys/time.h> 87 #include <sys/kernel.h> 88 #include <sys/systm.h> 89 #include <sys/sysctl.h> 90 #include <sys/proc.h> 91 #include <sys/buf.h> 92 #include <sys/syslog.h> 93 #include <sys/mount.h> 94 #include <sys/dirent.h> 95 #include <sys/signalvar.h> 96 #include <sys/vnode.h> 97 #include <sys/file.h> 98 #include <sys/filedesc.h> 99 #include <sys/kauth.h> 100 #include <sys/module.h> 101 102 #include <miscfs/genfs/genfs.h> 103 104 #include <miscfs/procfs/procfs.h> 105 106 #include <uvm/uvm_extern.h> /* for PAGE_SIZE */ 107 108 MODULE(MODULE_CLASS_VFS, procfs, "ptrace_common"); 109 110 VFS_PROTOS(procfs); 111 112 static struct sysctllog *procfs_sysctl_log; 113 114 static kauth_listener_t procfs_listener; 115 116 /* 117 * VFS Operations. 118 * 119 * mount system call 120 */ 121 /* ARGSUSED */ 122 int 123 procfs_mount( 124 struct mount *mp, 125 const char *path, 126 void *data, 127 size_t *data_len) 128 { 129 struct lwp *l = curlwp; 130 struct procfsmount *pmnt; 131 struct procfs_args *args = data; 132 int error; 133 134 if (args == NULL) 135 return EINVAL; 136 137 if (UIO_MX & (UIO_MX-1)) { 138 log(LOG_ERR, "procfs: invalid directory entry size"); 139 return (EINVAL); 140 } 141 142 if (mp->mnt_flag & MNT_GETARGS) { 143 if (*data_len < sizeof *args) 144 return EINVAL; 145 146 pmnt = VFSTOPROC(mp); 147 if (pmnt == NULL) 148 return EIO; 149 args->version = PROCFS_ARGSVERSION; 150 args->flags = pmnt->pmnt_flags; 151 *data_len = sizeof *args; 152 return 0; 153 } 154 155 if (mp->mnt_flag & MNT_UPDATE) 156 return (EOPNOTSUPP); 157 158 if (*data_len >= sizeof *args && args->version != PROCFS_ARGSVERSION) 159 return EINVAL; 160 161 pmnt = kmem_zalloc(sizeof(struct procfsmount), KM_SLEEP); 162 163 mp->mnt_stat.f_namemax = PROCFS_MAXNAMLEN; 164 mp->mnt_flag |= MNT_LOCAL; 165 mp->mnt_data = pmnt; 166 vfs_getnewfsid(mp); 167 168 error = set_statvfs_info(path, UIO_USERSPACE, "procfs", UIO_SYSSPACE, 169 mp->mnt_op->vfs_name, mp, l); 170 pmnt->pmnt_exechook = exechook_establish(procfs_revoke_vnodes, mp); 171 if (*data_len >= sizeof *args) 172 pmnt->pmnt_flags = args->flags; 173 else 174 pmnt->pmnt_flags = 0; 175 176 mp->mnt_iflag |= IMNT_MPSAFE; 177 return error; 178 } 179 180 /* 181 * unmount system call 182 */ 183 int 184 procfs_unmount(struct mount *mp, int mntflags) 185 { 186 int error; 187 int flags = 0; 188 189 if (mntflags & MNT_FORCE) 190 flags |= FORCECLOSE; 191 192 if ((error = vflush(mp, 0, flags)) != 0) 193 return (error); 194 195 exechook_disestablish(VFSTOPROC(mp)->pmnt_exechook); 196 197 kmem_free(mp->mnt_data, sizeof(struct procfsmount)); 198 mp->mnt_data = NULL; 199 200 return 0; 201 } 202 203 int 204 procfs_root(struct mount *mp, struct vnode **vpp) 205 { 206 int error; 207 208 error = procfs_allocvp(mp, vpp, 0, PFSroot, -1); 209 if (error == 0) { 210 error = vn_lock(*vpp, LK_EXCLUSIVE); 211 if (error != 0) { 212 vrele(*vpp); 213 *vpp = NULL; 214 } 215 } 216 217 return error; 218 } 219 220 /* ARGSUSED */ 221 int 222 procfs_start(struct mount *mp, int flags) 223 { 224 225 return (0); 226 } 227 228 /* 229 * Get file system statistics. 230 */ 231 int 232 procfs_statvfs(struct mount *mp, struct statvfs *sbp) 233 { 234 235 genfs_statvfs(mp, sbp); 236 237 sbp->f_bsize = PAGE_SIZE; 238 sbp->f_frsize = PAGE_SIZE; 239 sbp->f_iosize = PAGE_SIZE; 240 sbp->f_blocks = 1; 241 sbp->f_files = maxproc; /* approx */ 242 sbp->f_ffree = maxproc - nprocs; /* approx */ 243 sbp->f_favail = maxproc - nprocs; /* approx */ 244 245 return (0); 246 } 247 248 /*ARGSUSED*/ 249 int 250 procfs_sync( 251 struct mount *mp, 252 int waitfor, 253 kauth_cred_t uc) 254 { 255 256 return (0); 257 } 258 259 /*ARGSUSED*/ 260 int 261 procfs_vget(struct mount *mp, ino_t ino, 262 struct vnode **vpp) 263 { 264 return (EOPNOTSUPP); 265 } 266 267 int 268 procfs_loadvnode(struct mount *mp, struct vnode *vp, 269 const void *key, size_t key_len, const void **new_key) 270 { 271 int error; 272 struct pfskey pfskey; 273 struct pfsnode *pfs; 274 275 KASSERT(key_len == sizeof(pfskey)); 276 memcpy(&pfskey, key, key_len); 277 278 pfs = kmem_alloc(sizeof(*pfs), KM_SLEEP); 279 pfs->pfs_pid = pfskey.pk_pid; 280 pfs->pfs_type = pfskey.pk_type; 281 pfs->pfs_fd = pfskey.pk_fd; 282 pfs->pfs_vnode = vp; 283 pfs->pfs_flags = 0; 284 pfs->pfs_fileno = 285 PROCFS_FILENO(pfs->pfs_pid, pfs->pfs_type, pfs->pfs_fd); 286 vp->v_tag = VT_PROCFS; 287 vp->v_op = procfs_vnodeop_p; 288 vp->v_data = pfs; 289 290 switch (pfs->pfs_type) { 291 case PFSroot: /* /proc = dr-xr-xr-x */ 292 vp->v_vflag |= VV_ROOT; 293 /*FALLTHROUGH*/ 294 case PFSproc: /* /proc/N = dr-xr-xr-x */ 295 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 296 vp->v_type = VDIR; 297 break; 298 299 case PFStask: /* /proc/N/task = dr-xr-xr-x */ 300 if (pfs->pfs_fd == -1) { 301 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP| 302 S_IROTH|S_IXOTH; 303 vp->v_type = VDIR; 304 break; 305 } 306 /*FALLTHROUGH*/ 307 case PFScurproc: /* /proc/curproc = lr-xr-xr-x */ 308 case PFSself: /* /proc/self = lr-xr-xr-x */ 309 case PFScwd: /* /proc/N/cwd = lr-xr-xr-x */ 310 case PFSchroot: /* /proc/N/chroot = lr-xr-xr-x */ 311 case PFSexe: /* /proc/N/exe = lr-xr-xr-x */ 312 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 313 vp->v_type = VLNK; 314 break; 315 316 case PFSfd: 317 if (pfs->pfs_fd == -1) { /* /proc/N/fd = dr-x------ */ 318 pfs->pfs_mode = S_IRUSR|S_IXUSR; 319 vp->v_type = VDIR; 320 } else { /* /proc/N/fd/M = [ps-]rw------- */ 321 file_t *fp; 322 vnode_t *vxp; 323 struct proc *p; 324 325 mutex_enter(proc_lock); 326 p = proc_find(pfs->pfs_pid); 327 mutex_exit(proc_lock); 328 if (p == NULL) { 329 error = ENOENT; 330 goto bad; 331 } 332 KASSERT(rw_read_held(&p->p_reflock)); 333 if ((fp = fd_getfile2(p, pfs->pfs_fd)) == NULL) { 334 error = EBADF; 335 goto bad; 336 } 337 338 pfs->pfs_mode = S_IRUSR|S_IWUSR; 339 switch (fp->f_type) { 340 case DTYPE_VNODE: 341 vxp = fp->f_vnode; 342 343 /* 344 * We make symlinks for directories 345 * to avoid cycles. 346 */ 347 if (vxp->v_type == VDIR) 348 goto symlink; 349 vp->v_type = vxp->v_type; 350 break; 351 case DTYPE_PIPE: 352 vp->v_type = VFIFO; 353 break; 354 case DTYPE_SOCKET: 355 vp->v_type = VSOCK; 356 break; 357 case DTYPE_KQUEUE: 358 case DTYPE_MISC: 359 case DTYPE_SEM: 360 symlink: 361 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP| 362 S_IXGRP|S_IROTH|S_IXOTH; 363 vp->v_type = VLNK; 364 break; 365 default: 366 error = EOPNOTSUPP; 367 closef(fp); 368 goto bad; 369 } 370 closef(fp); 371 } 372 break; 373 374 case PFSfile: /* /proc/N/file = -rw------- */ 375 case PFSmem: /* /proc/N/mem = -rw------- */ 376 case PFSregs: /* /proc/N/regs = -rw------- */ 377 case PFSfpregs: /* /proc/N/fpregs = -rw------- */ 378 pfs->pfs_mode = S_IRUSR|S_IWUSR; 379 vp->v_type = VREG; 380 break; 381 382 case PFSctl: /* /proc/N/ctl = --w------ */ 383 case PFSnote: /* /proc/N/note = --w------ */ 384 case PFSnotepg: /* /proc/N/notepg = --w------ */ 385 pfs->pfs_mode = S_IWUSR; 386 vp->v_type = VREG; 387 break; 388 389 case PFSmap: /* /proc/N/map = -r--r--r-- */ 390 case PFSmaps: /* /proc/N/maps = -r--r--r-- */ 391 case PFSstatus: /* /proc/N/status = -r--r--r-- */ 392 case PFSstat: /* /proc/N/stat = -r--r--r-- */ 393 case PFScmdline: /* /proc/N/cmdline = -r--r--r-- */ 394 case PFSemul: /* /proc/N/emul = -r--r--r-- */ 395 case PFSmeminfo: /* /proc/meminfo = -r--r--r-- */ 396 case PFScpustat: /* /proc/stat = -r--r--r-- */ 397 case PFSdevices: /* /proc/devices = -r--r--r-- */ 398 case PFScpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 399 case PFSuptime: /* /proc/uptime = -r--r--r-- */ 400 case PFSmounts: /* /proc/mounts = -r--r--r-- */ 401 case PFSloadavg: /* /proc/loadavg = -r--r--r-- */ 402 case PFSstatm: /* /proc/N/statm = -r--r--r-- */ 403 case PFSversion: /* /proc/version = -r--r--r-- */ 404 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 405 vp->v_type = VREG; 406 break; 407 408 #ifdef __HAVE_PROCFS_MACHDEP 409 PROCFS_MACHDEP_NODETYPE_CASES 410 procfs_machdep_allocvp(vp); 411 break; 412 #endif 413 414 default: 415 panic("procfs_allocvp"); 416 } 417 418 uvm_vnp_setsize(vp, 0); 419 *new_key = &pfs->pfs_key; 420 421 return 0; 422 423 bad: 424 vp->v_tag =VT_NON; 425 vp->v_type = VNON; 426 vp->v_op = NULL; 427 vp->v_data = NULL; 428 kmem_free(pfs, sizeof(*pfs)); 429 return error; 430 } 431 432 void 433 procfs_init(void) 434 { 435 436 } 437 438 void 439 procfs_reinit(void) 440 { 441 442 } 443 444 void 445 procfs_done(void) 446 { 447 448 } 449 450 extern const struct vnodeopv_desc procfs_vnodeop_opv_desc; 451 452 const struct vnodeopv_desc * const procfs_vnodeopv_descs[] = { 453 &procfs_vnodeop_opv_desc, 454 NULL, 455 }; 456 457 struct vfsops procfs_vfsops = { 458 .vfs_name = MOUNT_PROCFS, 459 .vfs_min_mount_data = sizeof (struct procfs_args), 460 .vfs_mount = procfs_mount, 461 .vfs_start = procfs_start, 462 .vfs_unmount = procfs_unmount, 463 .vfs_root = procfs_root, 464 .vfs_quotactl = (void *)eopnotsupp, 465 .vfs_statvfs = procfs_statvfs, 466 .vfs_sync = procfs_sync, 467 .vfs_vget = procfs_vget, 468 .vfs_loadvnode = procfs_loadvnode, 469 .vfs_fhtovp = (void *)eopnotsupp, 470 .vfs_vptofh = (void *)eopnotsupp, 471 .vfs_init = procfs_init, 472 .vfs_reinit = procfs_reinit, 473 .vfs_done = procfs_done, 474 .vfs_snapshot = (void *)eopnotsupp, 475 .vfs_extattrctl = vfs_stdextattrctl, 476 .vfs_suspendctl = (void *)eopnotsupp, 477 .vfs_renamelock_enter = genfs_renamelock_enter, 478 .vfs_renamelock_exit = genfs_renamelock_exit, 479 .vfs_fsync = (void *)eopnotsupp, 480 .vfs_opv_descs = procfs_vnodeopv_descs 481 }; 482 483 static int 484 procfs_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 485 void *arg0, void *arg1, void *arg2, void *arg3) 486 { 487 struct proc *p; 488 struct pfsnode *pfs; 489 enum kauth_process_req req; 490 int result; 491 492 result = KAUTH_RESULT_DEFER; 493 p = arg0; 494 pfs = arg1; 495 req = (enum kauth_process_req)(unsigned long)arg2; 496 497 if (action != KAUTH_PROCESS_PROCFS) 498 return result; 499 500 /* Privileged; let secmodel handle that. */ 501 if (req == KAUTH_REQ_PROCESS_PROCFS_CTL) 502 return result; 503 504 switch (pfs->pfs_type) { 505 case PFSregs: 506 case PFSfpregs: 507 case PFSmem: 508 if (kauth_cred_getuid(cred) != kauth_cred_getuid(p->p_cred) || 509 ISSET(p->p_flag, PK_SUGID)) 510 break; 511 512 /*FALLTHROUGH*/ 513 default: 514 result = KAUTH_RESULT_ALLOW; 515 break; 516 } 517 518 return result; 519 } 520 521 522 static int 523 procfs_modcmd(modcmd_t cmd, void *arg) 524 { 525 int error; 526 527 switch (cmd) { 528 case MODULE_CMD_INIT: 529 error = vfs_attach(&procfs_vfsops); 530 if (error != 0) 531 break; 532 sysctl_createv(&procfs_sysctl_log, 0, NULL, NULL, 533 CTLFLAG_PERMANENT, 534 CTLTYPE_NODE, "procfs", 535 SYSCTL_DESCR("Process file system"), 536 NULL, 0, NULL, 0, 537 CTL_VFS, 12, CTL_EOL); 538 /* 539 * XXX the "12" above could be dynamic, thereby eliminating 540 * one more instance of the "number to vfs" mapping problem, 541 * but "12" is the order as taken from sys/mount.h 542 */ 543 544 procfs_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS, 545 procfs_listener_cb, NULL); 546 547 break; 548 case MODULE_CMD_FINI: 549 error = vfs_detach(&procfs_vfsops); 550 if (error != 0) 551 break; 552 sysctl_teardown(&procfs_sysctl_log); 553 kauth_unlisten_scope(procfs_listener); 554 break; 555 default: 556 error = ENOTTY; 557 break; 558 } 559 560 return (error); 561 } 562