procfs_vfsops.c revision 1.110
1 /* $NetBSD: procfs_vfsops.c,v 1.110 2020/12/28 22:36:16 riastradh 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 1.110 2020/12/28 22:36:16 riastradh Exp $"); 80 81 #if defined(_KERNEL_OPT) 82 #include "opt_compat_netbsd.h" 83 #endif 84 85 #include <sys/param.h> 86 #include <sys/atomic.h> 87 #include <sys/buf.h> 88 #include <sys/dirent.h> 89 #include <sys/file.h> 90 #include <sys/filedesc.h> 91 #include <sys/kauth.h> 92 #include <sys/kernel.h> 93 #include <sys/module.h> 94 #include <sys/mount.h> 95 #include <sys/proc.h> 96 #include <sys/signalvar.h> 97 #include <sys/sysctl.h> 98 #include <sys/syslog.h> 99 #include <sys/systm.h> 100 #include <sys/time.h> 101 #include <sys/vnode.h> 102 103 #include <miscfs/genfs/genfs.h> 104 105 #include <miscfs/procfs/procfs.h> 106 107 #include <uvm/uvm_extern.h> /* for PAGE_SIZE */ 108 109 MODULE(MODULE_CLASS_VFS, procfs, "ptrace_common"); 110 111 VFS_PROTOS(procfs); 112 113 static kauth_listener_t procfs_listener; 114 115 /* 116 * VFS Operations. 117 * 118 * mount system call 119 */ 120 /* ARGSUSED */ 121 int 122 procfs_mount( 123 struct mount *mp, 124 const char *path, 125 void *data, 126 size_t *data_len) 127 { 128 struct lwp *l = curlwp; 129 struct procfsmount *pmnt; 130 struct procfs_args *args = data; 131 int error; 132 133 if (args == NULL) 134 return EINVAL; 135 136 if (UIO_MX & (UIO_MX-1)) { 137 log(LOG_ERR, "procfs: invalid directory entry size"); 138 return (EINVAL); 139 } 140 141 if (mp->mnt_flag & MNT_GETARGS) { 142 if (*data_len < sizeof *args) 143 return EINVAL; 144 145 pmnt = VFSTOPROC(mp); 146 if (pmnt == NULL) 147 return EIO; 148 args->version = PROCFS_ARGSVERSION; 149 args->flags = pmnt->pmnt_flags; 150 *data_len = sizeof *args; 151 return 0; 152 } 153 154 if (mp->mnt_flag & MNT_UPDATE) 155 return (EOPNOTSUPP); 156 157 if (*data_len >= sizeof *args && args->version != PROCFS_ARGSVERSION) 158 return EINVAL; 159 160 pmnt = kmem_zalloc(sizeof(struct procfsmount), KM_SLEEP); 161 162 mp->mnt_stat.f_namemax = PROCFS_MAXNAMLEN; 163 mp->mnt_flag |= MNT_LOCAL; 164 mp->mnt_data = pmnt; 165 vfs_getnewfsid(mp); 166 167 error = set_statvfs_info(path, UIO_USERSPACE, "procfs", UIO_SYSSPACE, 168 mp->mnt_op->vfs_name, mp, l); 169 pmnt->pmnt_exechook = exechook_establish(procfs_revoke_vnodes, mp); 170 if (*data_len >= sizeof *args) 171 pmnt->pmnt_flags = args->flags; 172 else 173 pmnt->pmnt_flags = 0; 174 175 mp->mnt_iflag |= IMNT_MPSAFE | IMNT_SHRLOOKUP; 176 return error; 177 } 178 179 /* 180 * unmount system call 181 */ 182 int 183 procfs_unmount(struct mount *mp, int mntflags) 184 { 185 int error; 186 int flags = 0; 187 188 if (mntflags & MNT_FORCE) 189 flags |= FORCECLOSE; 190 191 if ((error = vflush(mp, 0, flags)) != 0) 192 return (error); 193 194 exechook_disestablish(VFSTOPROC(mp)->pmnt_exechook); 195 196 kmem_free(mp->mnt_data, sizeof(struct procfsmount)); 197 mp->mnt_data = NULL; 198 199 return 0; 200 } 201 202 int 203 procfs_root(struct mount *mp, int lktype, struct vnode **vpp) 204 { 205 int error; 206 207 error = procfs_allocvp(mp, vpp, 0, PFSroot, -1); 208 if (error == 0) { 209 error = vn_lock(*vpp, lktype); 210 if (error != 0) { 211 vrele(*vpp); 212 *vpp = NULL; 213 } 214 } 215 216 return error; 217 } 218 219 /* ARGSUSED */ 220 int 221 procfs_start(struct mount *mp, int flags) 222 { 223 224 return (0); 225 } 226 227 /* 228 * Get file system statistics. 229 */ 230 int 231 procfs_statvfs(struct mount *mp, struct statvfs *sbp) 232 { 233 234 genfs_statvfs(mp, sbp); 235 236 sbp->f_bsize = PAGE_SIZE; 237 sbp->f_frsize = PAGE_SIZE; 238 sbp->f_iosize = PAGE_SIZE; 239 sbp->f_blocks = 1; 240 sbp->f_files = maxproc; /* approx */ 241 sbp->f_ffree = maxproc - atomic_load_relaxed(&nprocs); /* approx */ 242 sbp->f_favail = maxproc - atomic_load_relaxed(&nprocs); /* approx */ 243 244 return (0); 245 } 246 247 /*ARGSUSED*/ 248 int 249 procfs_sync( 250 struct mount *mp, 251 int waitfor, 252 kauth_cred_t uc) 253 { 254 255 return (0); 256 } 257 258 /*ARGSUSED*/ 259 int 260 procfs_vget(struct mount *mp, ino_t ino, int lktype, 261 struct vnode **vpp) 262 { 263 return (EOPNOTSUPP); 264 } 265 266 int 267 procfs_loadvnode(struct mount *mp, struct vnode *vp, 268 const void *key, size_t key_len, const void **new_key) 269 { 270 int error; 271 struct pfskey pfskey; 272 struct pfsnode *pfs; 273 274 KASSERT(key_len == sizeof(pfskey)); 275 memcpy(&pfskey, key, key_len); 276 277 pfs = kmem_alloc(sizeof(*pfs), KM_SLEEP); 278 pfs->pfs_pid = pfskey.pk_pid; 279 pfs->pfs_type = pfskey.pk_type; 280 pfs->pfs_fd = pfskey.pk_fd; 281 pfs->pfs_vnode = vp; 282 pfs->pfs_flags = 0; 283 pfs->pfs_fileno = 284 PROCFS_FILENO(pfs->pfs_pid, pfs->pfs_type, pfs->pfs_fd); 285 vp->v_tag = VT_PROCFS; 286 vp->v_op = procfs_vnodeop_p; 287 vp->v_data = pfs; 288 289 switch (pfs->pfs_type) { 290 case PFSroot: /* /proc = dr-xr-xr-x */ 291 vp->v_vflag |= VV_ROOT; 292 /*FALLTHROUGH*/ 293 case PFSproc: /* /proc/N = dr-xr-xr-x */ 294 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 295 vp->v_type = VDIR; 296 break; 297 298 case PFStask: /* /proc/N/task = dr-xr-xr-x */ 299 if (pfs->pfs_fd == -1) { 300 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP| 301 S_IROTH|S_IXOTH; 302 vp->v_type = VDIR; 303 break; 304 } 305 /*FALLTHROUGH*/ 306 case PFScurproc: /* /proc/curproc = lr-xr-xr-x */ 307 case PFSself: /* /proc/self = lr-xr-xr-x */ 308 case PFScwd: /* /proc/N/cwd = lr-xr-xr-x */ 309 case PFSchroot: /* /proc/N/chroot = lr-xr-xr-x */ 310 case PFSexe: /* /proc/N/exe = lr-xr-xr-x */ 311 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 312 vp->v_type = VLNK; 313 break; 314 315 case PFSfd: 316 if (pfs->pfs_fd == -1) { /* /proc/N/fd = dr-x------ */ 317 pfs->pfs_mode = S_IRUSR|S_IXUSR; 318 vp->v_type = VDIR; 319 } else { /* /proc/N/fd/M = [ps-]rw------- */ 320 file_t *fp; 321 vnode_t *vxp; 322 struct proc *p; 323 324 mutex_enter(&proc_lock); 325 p = procfs_proc_find(mp, pfs->pfs_pid); 326 mutex_exit(&proc_lock); 327 if (p == NULL) { 328 error = ENOENT; 329 goto bad; 330 } 331 KASSERT(rw_read_held(&p->p_reflock)); 332 if ((fp = fd_getfile2(p, pfs->pfs_fd)) == NULL) { 333 error = EBADF; 334 goto bad; 335 } 336 337 pfs->pfs_mode = S_IRUSR|S_IWUSR; 338 switch (fp->f_type) { 339 case DTYPE_VNODE: 340 vxp = fp->f_vnode; 341 342 /* 343 * We make symlinks for directories 344 * to avoid cycles. 345 */ 346 if (vxp->v_type == VDIR) 347 goto symlink; 348 vp->v_type = vxp->v_type; 349 break; 350 case DTYPE_PIPE: 351 vp->v_type = VFIFO; 352 break; 353 case DTYPE_SOCKET: 354 vp->v_type = VSOCK; 355 break; 356 case DTYPE_KQUEUE: 357 case DTYPE_MISC: 358 case DTYPE_SEM: 359 symlink: 360 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP| 361 S_IXGRP|S_IROTH|S_IXOTH; 362 vp->v_type = VLNK; 363 break; 364 default: 365 error = EOPNOTSUPP; 366 closef(fp); 367 goto bad; 368 } 369 closef(fp); 370 } 371 break; 372 373 case PFSfile: /* /proc/N/file = -rw------- */ 374 case PFSmem: /* /proc/N/mem = -rw------- */ 375 case PFSregs: /* /proc/N/regs = -rw------- */ 376 case PFSfpregs: /* /proc/N/fpregs = -rw------- */ 377 pfs->pfs_mode = S_IRUSR|S_IWUSR; 378 vp->v_type = VREG; 379 break; 380 381 case PFSnote: /* /proc/N/note = --w------ */ 382 case PFSnotepg: /* /proc/N/notepg = --w------ */ 383 pfs->pfs_mode = S_IWUSR; 384 vp->v_type = VREG; 385 break; 386 387 case PFSmap: /* /proc/N/map = -r-------- */ 388 case PFSmaps: /* /proc/N/maps = -r-------- */ 389 case PFSauxv: /* /proc/N/auxv = -r-------- */ 390 case PFSenviron: /* /proc/N/environ = -r-------- */ 391 pfs->pfs_mode = S_IRUSR; 392 vp->v_type = VREG; 393 break; 394 395 case PFSstatus: /* /proc/N/status = -r--r--r-- */ 396 case PFSstat: /* /proc/N/stat = -r--r--r-- */ 397 case PFScmdline: /* /proc/N/cmdline = -r--r--r-- */ 398 case PFSemul: /* /proc/N/emul = -r--r--r-- */ 399 case PFSmeminfo: /* /proc/meminfo = -r--r--r-- */ 400 case PFScpustat: /* /proc/stat = -r--r--r-- */ 401 case PFSdevices: /* /proc/devices = -r--r--r-- */ 402 case PFScpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 403 case PFSuptime: /* /proc/uptime = -r--r--r-- */ 404 case PFSmounts: /* /proc/mounts = -r--r--r-- */ 405 case PFSloadavg: /* /proc/loadavg = -r--r--r-- */ 406 case PFSstatm: /* /proc/N/statm = -r--r--r-- */ 407 case PFSversion: /* /proc/version = -r--r--r-- */ 408 case PFSlimit: /* /proc/limit = -r--r--r-- */ 409 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 410 vp->v_type = VREG; 411 break; 412 413 #ifdef __HAVE_PROCFS_MACHDEP 414 PROCFS_MACHDEP_NODETYPE_CASES 415 procfs_machdep_allocvp(vp); 416 break; 417 #endif 418 419 default: 420 panic("procfs_allocvp"); 421 } 422 423 uvm_vnp_setsize(vp, 0); 424 *new_key = &pfs->pfs_key; 425 426 return 0; 427 428 bad: 429 vp->v_tag =VT_NON; 430 vp->v_type = VNON; 431 vp->v_op = NULL; 432 vp->v_data = NULL; 433 kmem_free(pfs, sizeof(*pfs)); 434 return error; 435 } 436 437 void 438 procfs_init(void) 439 { 440 441 } 442 443 void 444 procfs_reinit(void) 445 { 446 447 } 448 449 void 450 procfs_done(void) 451 { 452 453 } 454 455 extern const struct vnodeopv_desc procfs_vnodeop_opv_desc; 456 457 const struct vnodeopv_desc * const procfs_vnodeopv_descs[] = { 458 &procfs_vnodeop_opv_desc, 459 NULL, 460 }; 461 462 struct vfsops procfs_vfsops = { 463 .vfs_name = MOUNT_PROCFS, 464 .vfs_min_mount_data = sizeof (struct procfs_args), 465 .vfs_mount = procfs_mount, 466 .vfs_start = procfs_start, 467 .vfs_unmount = procfs_unmount, 468 .vfs_root = procfs_root, 469 .vfs_quotactl = (void *)eopnotsupp, 470 .vfs_statvfs = procfs_statvfs, 471 .vfs_sync = procfs_sync, 472 .vfs_vget = procfs_vget, 473 .vfs_loadvnode = procfs_loadvnode, 474 .vfs_fhtovp = (void *)eopnotsupp, 475 .vfs_vptofh = (void *)eopnotsupp, 476 .vfs_init = procfs_init, 477 .vfs_reinit = procfs_reinit, 478 .vfs_done = procfs_done, 479 .vfs_snapshot = (void *)eopnotsupp, 480 .vfs_extattrctl = vfs_stdextattrctl, 481 .vfs_suspendctl = genfs_suspendctl, 482 .vfs_renamelock_enter = genfs_renamelock_enter, 483 .vfs_renamelock_exit = genfs_renamelock_exit, 484 .vfs_fsync = (void *)eopnotsupp, 485 .vfs_opv_descs = procfs_vnodeopv_descs 486 }; 487 488 static int 489 procfs_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, 490 void *arg0, void *arg1, void *arg2, void *arg3) 491 { 492 struct proc *p; 493 struct pfsnode *pfs; 494 int result; 495 496 result = KAUTH_RESULT_DEFER; 497 p = arg0; 498 pfs = arg1; 499 500 if (action != KAUTH_PROCESS_PROCFS) 501 return result; 502 503 switch (pfs->pfs_type) { 504 case PFSregs: 505 case PFSfpregs: 506 case PFSmem: 507 if (kauth_cred_getuid(cred) != kauth_cred_getuid(p->p_cred) || 508 ISSET(p->p_flag, PK_SUGID)) 509 break; 510 511 /*FALLTHROUGH*/ 512 default: 513 result = KAUTH_RESULT_ALLOW; 514 break; 515 } 516 517 return result; 518 } 519 520 SYSCTL_SETUP(procfs_sysctl_setup, "procfs sysctl") 521 { 522 523 sysctl_createv(clog, 0, NULL, NULL, 524 CTLFLAG_PERMANENT, 525 CTLTYPE_NODE, "procfs", 526 SYSCTL_DESCR("Process file system"), 527 NULL, 0, NULL, 0, 528 CTL_VFS, 12, CTL_EOL); 529 /* 530 * XXX the "12" above could be dynamic, thereby eliminating 531 * one more instance of the "number to vfs" mapping problem, 532 * but "12" is the order as taken from sys/mount.h 533 */ 534 } 535 536 static int 537 procfs_modcmd(modcmd_t cmd, void *arg) 538 { 539 int error; 540 541 switch (cmd) { 542 case MODULE_CMD_INIT: 543 error = vfs_attach(&procfs_vfsops); 544 if (error != 0) 545 break; 546 547 procfs_listener = kauth_listen_scope(KAUTH_SCOPE_PROCESS, 548 procfs_listener_cb, NULL); 549 550 break; 551 case MODULE_CMD_FINI: 552 error = vfs_detach(&procfs_vfsops); 553 if (error != 0) 554 break; 555 kauth_unlisten_scope(procfs_listener); 556 break; 557 default: 558 error = ENOTTY; 559 break; 560 } 561 562 return (error); 563 } 564
Indexes created Mon Sep 29 21:09:56 GMT 2025