procfs_vfsops.c revision 1.103
1 /* $NetBSD: procfs_vfsops.c,v 1.103 2020/03/16 21:20:11 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 1.103 2020/03/16 21:20:11 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 kauth_listener_t procfs_listener; 113 114 /* 115 * VFS Operations. 116 * 117 * mount system call 118 */ 119 /* ARGSUSED */ 120 int 121 procfs_mount( 122 struct mount *mp, 123 const char *path, 124 void *data, 125 size_t *data_len) 126 { 127 struct lwp *l = curlwp; 128 struct procfsmount *pmnt; 129 struct procfs_args *args = data; 130 int error; 131 132 if (args == NULL) 133 return EINVAL; 134 135 if (UIO_MX & (UIO_MX-1)) { 136 log(LOG_ERR, "procfs: invalid directory entry size"); 137 return (EINVAL); 138 } 139 140 if (mp->mnt_flag & MNT_GETARGS) { 141 if (*data_len < sizeof *args) 142 return EINVAL; 143 144 pmnt = VFSTOPROC(mp); 145 if (pmnt == NULL) 146 return EIO; 147 args->version = PROCFS_ARGSVERSION; 148 args->flags = pmnt->pmnt_flags; 149 *data_len = sizeof *args; 150 return 0; 151 } 152 153 if (mp->mnt_flag & MNT_UPDATE) 154 return (EOPNOTSUPP); 155 156 if (*data_len >= sizeof *args && args->version != PROCFS_ARGSVERSION) 157 return EINVAL; 158 159 pmnt = kmem_zalloc(sizeof(struct procfsmount), KM_SLEEP); 160 161 mp->mnt_stat.f_namemax = PROCFS_MAXNAMLEN; 162 mp->mnt_flag |= MNT_LOCAL; 163 mp->mnt_data = pmnt; 164 vfs_getnewfsid(mp); 165 166 error = set_statvfs_info(path, UIO_USERSPACE, "procfs", UIO_SYSSPACE, 167 mp->mnt_op->vfs_name, mp, l); 168 pmnt->pmnt_exechook = exechook_establish(procfs_revoke_vnodes, mp); 169 if (*data_len >= sizeof *args) 170 pmnt->pmnt_flags = args->flags; 171 else 172 pmnt->pmnt_flags = 0; 173 174 mp->mnt_iflag |= IMNT_MPSAFE; 175 return error; 176 } 177 178 /* 179 * unmount system call 180 */ 181 int 182 procfs_unmount(struct mount *mp, int mntflags) 183 { 184 int error; 185 int flags = 0; 186 187 if (mntflags & MNT_FORCE) 188 flags |= FORCECLOSE; 189 190 if ((error = vflush(mp, 0, flags)) != 0) 191 return (error); 192 193 exechook_disestablish(VFSTOPROC(mp)->pmnt_exechook); 194 195 kmem_free(mp->mnt_data, sizeof(struct procfsmount)); 196 mp->mnt_data = NULL; 197 198 return 0; 199 } 200 201 int 202 procfs_root(struct mount *mp, int lktype, struct vnode **vpp) 203 { 204 int error; 205 206 error = procfs_allocvp(mp, vpp, 0, PFSroot, -1); 207 if (error == 0) { 208 error = vn_lock(*vpp, lktype); 209 if (error != 0) { 210 vrele(*vpp); 211 *vpp = NULL; 212 } 213 } 214 215 return error; 216 } 217 218 /* ARGSUSED */ 219 int 220 procfs_start(struct mount *mp, int flags) 221 { 222 223 return (0); 224 } 225 226 /* 227 * Get file system statistics. 228 */ 229 int 230 procfs_statvfs(struct mount *mp, struct statvfs *sbp) 231 { 232 233 genfs_statvfs(mp, sbp); 234 235 sbp->f_bsize = PAGE_SIZE; 236 sbp->f_frsize = PAGE_SIZE; 237 sbp->f_iosize = PAGE_SIZE; 238 sbp->f_blocks = 1; 239 sbp->f_files = maxproc; /* approx */ 240 sbp->f_ffree = maxproc - nprocs; /* approx */ 241 sbp->f_favail = maxproc - nprocs; /* approx */ 242 243 return (0); 244 } 245 246 /*ARGSUSED*/ 247 int 248 procfs_sync( 249 struct mount *mp, 250 int waitfor, 251 kauth_cred_t uc) 252 { 253 254 return (0); 255 } 256 257 /*ARGSUSED*/ 258 int 259 procfs_vget(struct mount *mp, ino_t ino, int lktype, 260 struct vnode **vpp) 261 { 262 return (EOPNOTSUPP); 263 } 264 265 int 266 procfs_loadvnode(struct mount *mp, struct vnode *vp, 267 const void *key, size_t key_len, const void **new_key) 268 { 269 int error; 270 struct pfskey pfskey; 271 struct pfsnode *pfs; 272 273 KASSERT(key_len == sizeof(pfskey)); 274 memcpy(&pfskey, key, key_len); 275 276 pfs = kmem_alloc(sizeof(*pfs), KM_SLEEP); 277 pfs->pfs_pid = pfskey.pk_pid; 278 pfs->pfs_type = pfskey.pk_type; 279 pfs->pfs_fd = pfskey.pk_fd; 280 pfs->pfs_vnode = vp; 281 pfs->pfs_flags = 0; 282 pfs->pfs_fileno = 283 PROCFS_FILENO(pfs->pfs_pid, pfs->pfs_type, pfs->pfs_fd); 284 vp->v_tag = VT_PROCFS; 285 vp->v_op = procfs_vnodeop_p; 286 vp->v_data = pfs; 287 288 switch (pfs->pfs_type) { 289 case PFSroot: /* /proc = dr-xr-xr-x */ 290 vp->v_vflag |= VV_ROOT; 291 /*FALLTHROUGH*/ 292 case PFSproc: /* /proc/N = dr-xr-xr-x */ 293 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 294 vp->v_type = VDIR; 295 break; 296 297 case PFStask: /* /proc/N/task = dr-xr-xr-x */ 298 if (pfs->pfs_fd == -1) { 299 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP| 300 S_IROTH|S_IXOTH; 301 vp->v_type = VDIR; 302 break; 303 } 304 /*FALLTHROUGH*/ 305 case PFScurproc: /* /proc/curproc = lr-xr-xr-x */ 306 case PFSself: /* /proc/self = lr-xr-xr-x */ 307 case PFScwd: /* /proc/N/cwd = lr-xr-xr-x */ 308 case PFSchroot: /* /proc/N/chroot = lr-xr-xr-x */ 309 case PFSexe: /* /proc/N/exe = lr-xr-xr-x */ 310 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 311 vp->v_type = VLNK; 312 break; 313 314 case PFSfd: 315 if (pfs->pfs_fd == -1) { /* /proc/N/fd = dr-x------ */ 316 pfs->pfs_mode = S_IRUSR|S_IXUSR; 317 vp->v_type = VDIR; 318 } else { /* /proc/N/fd/M = [ps-]rw------- */ 319 file_t *fp; 320 vnode_t *vxp; 321 struct proc *p; 322 323 mutex_enter(proc_lock); 324 p = proc_find(pfs->pfs_pid); 325 mutex_exit(proc_lock); 326 if (p == NULL) { 327 error = ENOENT; 328 goto bad; 329 } 330 KASSERT(rw_read_held(&p->p_reflock)); 331 if ((fp = fd_getfile2(p, pfs->pfs_fd)) == NULL) { 332 error = EBADF; 333 goto bad; 334 } 335 336 pfs->pfs_mode = S_IRUSR|S_IWUSR; 337 switch (fp->f_type) { 338 case DTYPE_VNODE: 339 vxp = fp->f_vnode; 340 341 /* 342 * We make symlinks for directories 343 * to avoid cycles. 344 */ 345 if (vxp->v_type == VDIR) 346 goto symlink; 347 vp->v_type = vxp->v_type; 348 break; 349 case DTYPE_PIPE: 350 vp->v_type = VFIFO; 351 break; 352 case DTYPE_SOCKET: 353 vp->v_type = VSOCK; 354 break; 355 case DTYPE_KQUEUE: 356 case DTYPE_MISC: 357 case DTYPE_SEM: 358 symlink: 359 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP| 360 S_IXGRP|S_IROTH|S_IXOTH; 361 vp->v_type = VLNK; 362 break; 363 default: 364 error = EOPNOTSUPP; 365 closef(fp); 366 goto bad; 367 } 368 closef(fp); 369 } 370 break; 371 372 case PFSfile: /* /proc/N/file = -rw------- */ 373 case PFSmem: /* /proc/N/mem = -rw------- */ 374 case PFSregs: /* /proc/N/regs = -rw------- */ 375 case PFSfpregs: /* /proc/N/fpregs = -rw------- */ 376 pfs->pfs_mode = S_IRUSR|S_IWUSR; 377 vp->v_type = VREG; 378 break; 379 380 case PFSnote: /* /proc/N/note = --w------ */ 381 case PFSnotepg: /* /proc/N/notepg = --w------ */ 382 pfs->pfs_mode = S_IWUSR; 383 vp->v_type = VREG; 384 break; 385 386 case PFSmap: /* /proc/N/map = -r-------- */ 387 case PFSmaps: /* /proc/N/maps = -r-------- */ 388 case PFSauxv: /* /proc/N/auxv = -r-------- */ 389 pfs->pfs_mode = S_IRUSR; 390 vp->v_type = VREG; 391 break; 392 393 case PFSstatus: /* /proc/N/status = -r--r--r-- */ 394 case PFSstat: /* /proc/N/stat = -r--r--r-- */ 395 case PFScmdline: /* /proc/N/cmdline = -r--r--r-- */ 396 case PFSenviron: /* /proc/N/environ = -r--r--r-- */ 397 case PFSemul: /* /proc/N/emul = -r--r--r-- */ 398 case PFSmeminfo: /* /proc/meminfo = -r--r--r-- */ 399 case PFScpustat: /* /proc/stat = -r--r--r-- */ 400 case PFSdevices: /* /proc/devices = -r--r--r-- */ 401 case PFScpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 402 case PFSuptime: /* /proc/uptime = -r--r--r-- */ 403 case PFSmounts: /* /proc/mounts = -r--r--r-- */ 404 case PFSloadavg: /* /proc/loadavg = -r--r--r-- */ 405 case PFSstatm: /* /proc/N/statm = -r--r--r-- */ 406 case PFSversion: /* /proc/version = -r--r--r-- */ 407 case PFSlimit: /* /proc/limit = -r--r--r-- */ 408 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 409 vp->v_type = VREG; 410 break; 411 412 #ifdef __HAVE_PROCFS_MACHDEP 413 PROCFS_MACHDEP_NODETYPE_CASES 414 procfs_machdep_allocvp(vp); 415 break; 416 #endif 417 418 default: 419 panic("procfs_allocvp"); 420 } 421 422 uvm_vnp_setsize(vp, 0); 423 *new_key = &pfs->pfs_key; 424 425 return 0; 426 427 bad: 428 vp->v_tag =VT_NON; 429 vp->v_type = VNON; 430 vp->v_op = NULL; 431 vp->v_data = NULL; 432 kmem_free(pfs, sizeof(*pfs)); 433 return error; 434 } 435 436 void 437 procfs_init(void) 438 { 439 440 } 441 442 void 443 procfs_reinit(void) 444 { 445 446 } 447 448 void 449 procfs_done(void) 450 { 451 452 } 453 454 extern const struct vnodeopv_desc procfs_vnodeop_opv_desc; 455 456 const struct vnodeopv_desc * const procfs_vnodeopv_descs[] = { 457 &procfs_vnodeop_opv_desc, 458 NULL, 459 }; 460 461 struct vfsops procfs_vfsops = { 462 .vfs_name = MOUNT_PROCFS, 463 .vfs_min_mount_data = sizeof (struct procfs_args), 464 .vfs_mount = procfs_mount, 465 .vfs_start = procfs_start, 466 .vfs_unmount = procfs_unmount, 467 .vfs_root = procfs_root, 468 .vfs_quotactl = (void *)eopnotsupp, 469 .vfs_statvfs = procfs_statvfs, 470 .vfs_sync = procfs_sync, 471 .vfs_vget = procfs_vget, 472 .vfs_loadvnode = procfs_loadvnode, 473 .vfs_fhtovp = (void *)eopnotsupp, 474 .vfs_vptofh = (void *)eopnotsupp, 475 .vfs_init = procfs_init, 476 .vfs_reinit = procfs_reinit, 477 .vfs_done = procfs_done, 478 .vfs_snapshot = (void *)eopnotsupp, 479 .vfs_extattrctl = vfs_stdextattrctl, 480 .vfs_suspendctl = genfs_suspendctl, 481 .vfs_renamelock_enter = genfs_renamelock_enter, 482 .vfs_renamelock_exit = genfs_renamelock_exit, 483 .vfs_fsync = (void *)eopnotsupp, 484 .vfs_opv_descs = procfs_vnodeopv_descs 485 }; 486 487 static int 488 procfs_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 489 void *arg0, void *arg1, void *arg2, void *arg3) 490 { 491 struct proc *p; 492 struct pfsnode *pfs; 493 int result; 494 495 result = KAUTH_RESULT_DEFER; 496 p = arg0; 497 pfs = arg1; 498 499 if (action != KAUTH_PROCESS_PROCFS) 500 return result; 501 502 switch (pfs->pfs_type) { 503 case PFSregs: 504 case PFSfpregs: 505 case PFSmem: 506 if (kauth_cred_getuid(cred) != kauth_cred_getuid(p->p_cred) || 507 ISSET(p->p_flag, PK_SUGID)) 508 break; 509 510 /*FALLTHROUGH*/ 511 default: 512 result = KAUTH_RESULT_ALLOW; 513 break; 514 } 515 516 return result; 517 } 518 519 SYSCTL_SETUP(procfs_sysctl_setup, "procfs sysctl") 520 { 521 522 sysctl_createv(clog, 0, NULL, NULL, 523 CTLFLAG_PERMANENT, 524 CTLTYPE_NODE, "procfs", 525 SYSCTL_DESCR("Process file system"), 526 NULL, 0, NULL, 0, 527 CTL_VFS, 12, CTL_EOL); 528 /* 529 * XXX the "12" above could be dynamic, thereby eliminating 530 * one more instance of the "number to vfs" mapping problem, 531 * but "12" is the order as taken from sys/mount.h 532 */ 533 } 534 535 static int 536 procfs_modcmd(modcmd_t cmd, void *arg) 537 { 538 int error; 539 540 switch (cmd) { 541 case MODULE_CMD_INIT: 542 error = vfs_attach(&procfs_vfsops); 543 if (error != 0) 544 break; 545 546 procfs_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS, 547 procfs_listener_cb, NULL); 548 549 break; 550 case MODULE_CMD_FINI: 551 error = vfs_detach(&procfs_vfsops); 552 if (error != 0) 553 break; 554 kauth_unlisten_scope(procfs_listener); 555 break; 556 default: 557 error = ENOTTY; 558 break; 559 } 560 561 return (error); 562 } 563
Indexes created Mon Sep 29 21:09:56 GMT 2025