1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1989, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include "opt_capsicum.h" 38 #include "opt_ddb.h" 39 #include "opt_ktrace.h" 40 41 #include <sys/systm.h> 42 #include <sys/capsicum.h> 43 #include <sys/conf.h> 44 #include <sys/fcntl.h> 45 #include <sys/file.h> 46 #include <sys/filedesc.h> 47 #include <sys/filio.h> 48 #include <sys/jail.h> 49 #include <sys/kernel.h> 50 #include <sys/limits.h> 51 #include <sys/lock.h> 52 #include <sys/malloc.h> 53 #include <sys/mount.h> 54 #include <sys/mutex.h> 55 #include <sys/namei.h> 56 #include <sys/selinfo.h> 57 #include <sys/poll.h> 58 #include <sys/priv.h> 59 #include <sys/proc.h> 60 #include <sys/protosw.h> 61 #include <sys/racct.h> 62 #include <sys/resourcevar.h> 63 #include <sys/sbuf.h> 64 #include <sys/signalvar.h> 65 #include <sys/kdb.h> 66 #include <sys/smr.h> 67 #include <sys/stat.h> 68 #include <sys/sx.h> 69 #include <sys/syscallsubr.h> 70 #include <sys/sysctl.h> 71 #include <sys/sysproto.h> 72 #include <sys/unistd.h> 73 #include <sys/user.h> 74 #include <sys/vnode.h> 75 #include <sys/ktrace.h> 76 77 #include <net/vnet.h> 78 79 #include <security/audit/audit.h> 80 81 #include <vm/uma.h> 82 #include <vm/vm.h> 83 84 #include <ddb/ddb.h> 85 86 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 87 static MALLOC_DEFINE(M_PWD, "pwd", "Descriptor table vnodes"); 88 static MALLOC_DEFINE(M_PWDDESC, "pwddesc", "Pwd descriptors"); 89 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 90 "file desc to leader structures"); 91 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 92 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 93 94 MALLOC_DECLARE(M_FADVISE); 95 96 static __read_mostly uma_zone_t file_zone; 97 static __read_mostly uma_zone_t filedesc0_zone; 98 __read_mostly uma_zone_t pwd_zone; 99 VFS_SMR_DECLARE; 100 101 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 102 struct thread *td, bool holdleaders, bool audit); 103 static void export_file_to_kinfo(struct file *fp, int fd, 104 cap_rights_t *rightsp, struct kinfo_file *kif, 105 struct filedesc *fdp, int flags); 106 static int fd_first_free(struct filedesc *fdp, int low, int size); 107 static void fdgrowtable(struct filedesc *fdp, int nfd); 108 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 109 static void fdunused(struct filedesc *fdp, int fd); 110 static void fdused(struct filedesc *fdp, int fd); 111 static int fget_unlocked_seq(struct thread *td, int fd, 112 const cap_rights_t *needrightsp, struct file **fpp, 113 seqc_t *seqp); 114 static int getmaxfd(struct thread *td); 115 static u_long *filecaps_copy_prep(const struct filecaps *src); 116 static void filecaps_copy_finish(const struct filecaps *src, 117 struct filecaps *dst, u_long *ioctls); 118 static u_long *filecaps_free_prep(struct filecaps *fcaps); 119 static void filecaps_free_finish(u_long *ioctls); 120 121 static struct pwd *pwd_alloc(void); 122 123 /* 124 * Each process has: 125 * 126 * - An array of open file descriptors (fd_ofiles) 127 * - An array of file flags (fd_ofileflags) 128 * - A bitmap recording which descriptors are in use (fd_map) 129 * 130 * A process starts out with NDFILE descriptors. The value of NDFILE has 131 * been selected based the historical limit of 20 open files, and an 132 * assumption that the majority of processes, especially short-lived 133 * processes like shells, will never need more. 134 * 135 * If this initial allocation is exhausted, a larger descriptor table and 136 * map are allocated dynamically, and the pointers in the process's struct 137 * filedesc are updated to point to those. This is repeated every time 138 * the process runs out of file descriptors (provided it hasn't hit its 139 * resource limit). 140 * 141 * Since threads may hold references to individual descriptor table 142 * entries, the tables are never freed. Instead, they are placed on a 143 * linked list and freed only when the struct filedesc is released. 144 */ 145 #define NDFILE 20 146 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 147 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 148 #define NDSLOT(x) ((x) / NDENTRIES) 149 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 150 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 151 152 #define FILEDESC_FOREACH_FDE(fdp, _iterator, _fde) \ 153 struct filedesc *_fdp = (fdp); \ 154 int _lastfile = fdlastfile_single(_fdp); \ 155 for (_iterator = 0; _iterator <= _lastfile; _iterator++) \ 156 if ((_fde = &_fdp->fd_ofiles[_iterator])->fde_file != NULL) 157 158 #define FILEDESC_FOREACH_FP(fdp, _iterator, _fp) \ 159 struct filedesc *_fdp = (fdp); \ 160 int _lastfile = fdlastfile_single(_fdp); \ 161 for (_iterator = 0; _iterator <= _lastfile; _iterator++) \ 162 if ((_fp = _fdp->fd_ofiles[_iterator].fde_file) != NULL) 163 164 /* 165 * SLIST entry used to keep track of ofiles which must be reclaimed when 166 * the process exits. 167 */ 168 struct freetable { 169 struct fdescenttbl *ft_table; 170 SLIST_ENTRY(freetable) ft_next; 171 }; 172 173 /* 174 * Initial allocation: a filedesc structure + the head of SLIST used to 175 * keep track of old ofiles + enough space for NDFILE descriptors. 176 */ 177 178 struct fdescenttbl0 { 179 int fdt_nfiles; 180 struct filedescent fdt_ofiles[NDFILE]; 181 }; 182 183 struct filedesc0 { 184 struct filedesc fd_fd; 185 SLIST_HEAD(, freetable) fd_free; 186 struct fdescenttbl0 fd_dfiles; 187 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 188 }; 189 190 /* 191 * Descriptor management. 192 */ 193 static int __exclusive_cache_line openfiles; /* actual number of open files */ 194 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 195 void __read_mostly (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 196 197 /* 198 * If low >= size, just return low. Otherwise find the first zero bit in the 199 * given bitmap, starting at low and not exceeding size - 1. Return size if 200 * not found. 201 */ 202 static int 203 fd_first_free(struct filedesc *fdp, int low, int size) 204 { 205 NDSLOTTYPE *map = fdp->fd_map; 206 NDSLOTTYPE mask; 207 int off, maxoff; 208 209 if (low >= size) 210 return (low); 211 212 off = NDSLOT(low); 213 if (low % NDENTRIES) { 214 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 215 if ((mask &= ~map[off]) != 0UL) 216 return (off * NDENTRIES + ffsl(mask) - 1); 217 ++off; 218 } 219 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 220 if (map[off] != ~0UL) 221 return (off * NDENTRIES + ffsl(~map[off]) - 1); 222 return (size); 223 } 224 225 /* 226 * Find the last used fd. 227 * 228 * Call this variant if fdp can't be modified by anyone else (e.g, during exec). 229 * Otherwise use fdlastfile. 230 */ 231 int 232 fdlastfile_single(struct filedesc *fdp) 233 { 234 NDSLOTTYPE *map = fdp->fd_map; 235 int off, minoff; 236 237 off = NDSLOT(fdp->fd_nfiles - 1); 238 for (minoff = NDSLOT(0); off >= minoff; --off) 239 if (map[off] != 0) 240 return (off * NDENTRIES + flsl(map[off]) - 1); 241 return (-1); 242 } 243 244 int 245 fdlastfile(struct filedesc *fdp) 246 { 247 248 FILEDESC_LOCK_ASSERT(fdp); 249 return (fdlastfile_single(fdp)); 250 } 251 252 static int 253 fdisused(struct filedesc *fdp, int fd) 254 { 255 256 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 257 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 258 259 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 260 } 261 262 /* 263 * Mark a file descriptor as used. 264 */ 265 static void 266 fdused_init(struct filedesc *fdp, int fd) 267 { 268 269 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 270 271 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 272 } 273 274 static void 275 fdused(struct filedesc *fdp, int fd) 276 { 277 278 FILEDESC_XLOCK_ASSERT(fdp); 279 280 fdused_init(fdp, fd); 281 if (fd == fdp->fd_freefile) 282 fdp->fd_freefile++; 283 } 284 285 /* 286 * Mark a file descriptor as unused. 287 */ 288 static void 289 fdunused(struct filedesc *fdp, int fd) 290 { 291 292 FILEDESC_XLOCK_ASSERT(fdp); 293 294 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 295 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 296 ("fd=%d is still in use", fd)); 297 298 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 299 if (fd < fdp->fd_freefile) 300 fdp->fd_freefile = fd; 301 } 302 303 /* 304 * Free a file descriptor. 305 * 306 * Avoid some work if fdp is about to be destroyed. 307 */ 308 static inline void 309 fdefree_last(struct filedescent *fde) 310 { 311 312 filecaps_free(&fde->fde_caps); 313 } 314 315 static inline void 316 fdfree(struct filedesc *fdp, int fd) 317 { 318 struct filedescent *fde; 319 320 FILEDESC_XLOCK_ASSERT(fdp); 321 fde = &fdp->fd_ofiles[fd]; 322 #ifdef CAPABILITIES 323 seqc_write_begin(&fde->fde_seqc); 324 #endif 325 fde->fde_file = NULL; 326 #ifdef CAPABILITIES 327 seqc_write_end(&fde->fde_seqc); 328 #endif 329 fdefree_last(fde); 330 fdunused(fdp, fd); 331 } 332 333 /* 334 * System calls on descriptors. 335 */ 336 #ifndef _SYS_SYSPROTO_H_ 337 struct getdtablesize_args { 338 int dummy; 339 }; 340 #endif 341 /* ARGSUSED */ 342 int 343 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 344 { 345 #ifdef RACCT 346 uint64_t lim; 347 #endif 348 349 td->td_retval[0] = getmaxfd(td); 350 #ifdef RACCT 351 PROC_LOCK(td->td_proc); 352 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 353 PROC_UNLOCK(td->td_proc); 354 if (lim < td->td_retval[0]) 355 td->td_retval[0] = lim; 356 #endif 357 return (0); 358 } 359 360 /* 361 * Duplicate a file descriptor to a particular value. 362 * 363 * Note: keep in mind that a potential race condition exists when closing 364 * descriptors from a shared descriptor table (via rfork). 365 */ 366 #ifndef _SYS_SYSPROTO_H_ 367 struct dup2_args { 368 u_int from; 369 u_int to; 370 }; 371 #endif 372 /* ARGSUSED */ 373 int 374 sys_dup2(struct thread *td, struct dup2_args *uap) 375 { 376 377 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to)); 378 } 379 380 /* 381 * Duplicate a file descriptor. 382 */ 383 #ifndef _SYS_SYSPROTO_H_ 384 struct dup_args { 385 u_int fd; 386 }; 387 #endif 388 /* ARGSUSED */ 389 int 390 sys_dup(struct thread *td, struct dup_args *uap) 391 { 392 393 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0)); 394 } 395 396 /* 397 * The file control system call. 398 */ 399 #ifndef _SYS_SYSPROTO_H_ 400 struct fcntl_args { 401 int fd; 402 int cmd; 403 long arg; 404 }; 405 #endif 406 /* ARGSUSED */ 407 int 408 sys_fcntl(struct thread *td, struct fcntl_args *uap) 409 { 410 411 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg)); 412 } 413 414 int 415 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, intptr_t arg) 416 { 417 struct flock fl; 418 struct __oflock ofl; 419 intptr_t arg1; 420 int error, newcmd; 421 422 error = 0; 423 newcmd = cmd; 424 switch (cmd) { 425 case F_OGETLK: 426 case F_OSETLK: 427 case F_OSETLKW: 428 /* 429 * Convert old flock structure to new. 430 */ 431 error = copyin((void *)arg, &ofl, sizeof(ofl)); 432 fl.l_start = ofl.l_start; 433 fl.l_len = ofl.l_len; 434 fl.l_pid = ofl.l_pid; 435 fl.l_type = ofl.l_type; 436 fl.l_whence = ofl.l_whence; 437 fl.l_sysid = 0; 438 439 switch (cmd) { 440 case F_OGETLK: 441 newcmd = F_GETLK; 442 break; 443 case F_OSETLK: 444 newcmd = F_SETLK; 445 break; 446 case F_OSETLKW: 447 newcmd = F_SETLKW; 448 break; 449 } 450 arg1 = (intptr_t)&fl; 451 break; 452 case F_GETLK: 453 case F_SETLK: 454 case F_SETLKW: 455 case F_SETLK_REMOTE: 456 error = copyin((void *)arg, &fl, sizeof(fl)); 457 arg1 = (intptr_t)&fl; 458 break; 459 default: 460 arg1 = arg; 461 break; 462 } 463 if (error) 464 return (error); 465 error = kern_fcntl(td, fd, newcmd, arg1); 466 if (error) 467 return (error); 468 if (cmd == F_OGETLK) { 469 ofl.l_start = fl.l_start; 470 ofl.l_len = fl.l_len; 471 ofl.l_pid = fl.l_pid; 472 ofl.l_type = fl.l_type; 473 ofl.l_whence = fl.l_whence; 474 error = copyout(&ofl, (void *)arg, sizeof(ofl)); 475 } else if (cmd == F_GETLK) { 476 error = copyout(&fl, (void *)arg, sizeof(fl)); 477 } 478 return (error); 479 } 480 481 int 482 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 483 { 484 struct filedesc *fdp; 485 struct flock *flp; 486 struct file *fp, *fp2; 487 struct filedescent *fde; 488 struct proc *p; 489 struct vnode *vp; 490 struct mount *mp; 491 struct kinfo_file *kif; 492 int error, flg, kif_sz, seals, tmp, got_set, got_cleared; 493 uint64_t bsize; 494 off_t foffset; 495 496 error = 0; 497 flg = F_POSIX; 498 p = td->td_proc; 499 fdp = p->p_fd; 500 501 AUDIT_ARG_FD(cmd); 502 AUDIT_ARG_CMD(cmd); 503 switch (cmd) { 504 case F_DUPFD: 505 tmp = arg; 506 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp); 507 break; 508 509 case F_DUPFD_CLOEXEC: 510 tmp = arg; 511 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp); 512 break; 513 514 case F_DUP2FD: 515 tmp = arg; 516 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp); 517 break; 518 519 case F_DUP2FD_CLOEXEC: 520 tmp = arg; 521 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp); 522 break; 523 524 case F_GETFD: 525 error = EBADF; 526 FILEDESC_SLOCK(fdp); 527 fde = fdeget_noref(fdp, fd); 528 if (fde != NULL) { 529 td->td_retval[0] = 530 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 531 error = 0; 532 } 533 FILEDESC_SUNLOCK(fdp); 534 break; 535 536 case F_SETFD: 537 error = EBADF; 538 FILEDESC_XLOCK(fdp); 539 fde = fdeget_noref(fdp, fd); 540 if (fde != NULL) { 541 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 542 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 543 error = 0; 544 } 545 FILEDESC_XUNLOCK(fdp); 546 break; 547 548 case F_GETFL: 549 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETFL, &fp); 550 if (error != 0) 551 break; 552 td->td_retval[0] = OFLAGS(fp->f_flag); 553 fdrop(fp, td); 554 break; 555 556 case F_SETFL: 557 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETFL, &fp); 558 if (error != 0) 559 break; 560 if (fp->f_ops == &path_fileops) { 561 fdrop(fp, td); 562 error = EBADF; 563 break; 564 } 565 do { 566 tmp = flg = fp->f_flag; 567 tmp &= ~FCNTLFLAGS; 568 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 569 } while (atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 570 got_set = tmp & ~flg; 571 got_cleared = flg & ~tmp; 572 tmp = fp->f_flag & FNONBLOCK; 573 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 574 if (error != 0) 575 goto revert_f_setfl; 576 tmp = fp->f_flag & FASYNC; 577 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 578 if (error == 0) { 579 fdrop(fp, td); 580 break; 581 } 582 atomic_clear_int(&fp->f_flag, FNONBLOCK); 583 tmp = 0; 584 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 585 revert_f_setfl: 586 do { 587 tmp = flg = fp->f_flag; 588 tmp &= ~FCNTLFLAGS; 589 tmp |= got_cleared; 590 tmp &= ~got_set; 591 } while (atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 592 fdrop(fp, td); 593 break; 594 595 case F_GETOWN: 596 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETOWN, &fp); 597 if (error != 0) 598 break; 599 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 600 if (error == 0) 601 td->td_retval[0] = tmp; 602 fdrop(fp, td); 603 break; 604 605 case F_SETOWN: 606 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETOWN, &fp); 607 if (error != 0) 608 break; 609 tmp = arg; 610 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 611 fdrop(fp, td); 612 break; 613 614 case F_SETLK_REMOTE: 615 error = priv_check(td, PRIV_NFS_LOCKD); 616 if (error != 0) 617 return (error); 618 flg = F_REMOTE; 619 goto do_setlk; 620 621 case F_SETLKW: 622 flg |= F_WAIT; 623 /* FALLTHROUGH F_SETLK */ 624 625 case F_SETLK: 626 do_setlk: 627 flp = (struct flock *)arg; 628 if ((flg & F_REMOTE) != 0 && flp->l_sysid == 0) { 629 error = EINVAL; 630 break; 631 } 632 633 error = fget_unlocked(td, fd, &cap_flock_rights, &fp); 634 if (error != 0) 635 break; 636 if (fp->f_type != DTYPE_VNODE || fp->f_ops == &path_fileops) { 637 error = EBADF; 638 fdrop(fp, td); 639 break; 640 } 641 642 if (flp->l_whence == SEEK_CUR) { 643 foffset = foffset_get(fp); 644 if (foffset < 0 || 645 (flp->l_start > 0 && 646 foffset > OFF_MAX - flp->l_start)) { 647 error = EOVERFLOW; 648 fdrop(fp, td); 649 break; 650 } 651 flp->l_start += foffset; 652 } 653 654 vp = fp->f_vnode; 655 switch (flp->l_type) { 656 case F_RDLCK: 657 if ((fp->f_flag & FREAD) == 0) { 658 error = EBADF; 659 break; 660 } 661 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { 662 PROC_LOCK(p->p_leader); 663 p->p_leader->p_flag |= P_ADVLOCK; 664 PROC_UNLOCK(p->p_leader); 665 } 666 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 667 flp, flg); 668 break; 669 case F_WRLCK: 670 if ((fp->f_flag & FWRITE) == 0) { 671 error = EBADF; 672 break; 673 } 674 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { 675 PROC_LOCK(p->p_leader); 676 p->p_leader->p_flag |= P_ADVLOCK; 677 PROC_UNLOCK(p->p_leader); 678 } 679 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 680 flp, flg); 681 break; 682 case F_UNLCK: 683 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 684 flp, flg); 685 break; 686 case F_UNLCKSYS: 687 if (flg != F_REMOTE) { 688 error = EINVAL; 689 break; 690 } 691 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 692 F_UNLCKSYS, flp, flg); 693 break; 694 default: 695 error = EINVAL; 696 break; 697 } 698 if (error != 0 || flp->l_type == F_UNLCK || 699 flp->l_type == F_UNLCKSYS) { 700 fdrop(fp, td); 701 break; 702 } 703 704 /* 705 * Check for a race with close. 706 * 707 * The vnode is now advisory locked (or unlocked, but this case 708 * is not really important) as the caller requested. 709 * We had to drop the filedesc lock, so we need to recheck if 710 * the descriptor is still valid, because if it was closed 711 * in the meantime we need to remove advisory lock from the 712 * vnode - close on any descriptor leading to an advisory 713 * locked vnode, removes that lock. 714 * We will return 0 on purpose in that case, as the result of 715 * successful advisory lock might have been externally visible 716 * already. This is fine - effectively we pretend to the caller 717 * that the closing thread was a bit slower and that the 718 * advisory lock succeeded before the close. 719 */ 720 error = fget_unlocked(td, fd, &cap_no_rights, &fp2); 721 if (error != 0) { 722 fdrop(fp, td); 723 break; 724 } 725 if (fp != fp2) { 726 flp->l_whence = SEEK_SET; 727 flp->l_start = 0; 728 flp->l_len = 0; 729 flp->l_type = F_UNLCK; 730 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 731 F_UNLCK, flp, F_POSIX); 732 } 733 fdrop(fp, td); 734 fdrop(fp2, td); 735 break; 736 737 case F_GETLK: 738 error = fget_unlocked(td, fd, &cap_flock_rights, &fp); 739 if (error != 0) 740 break; 741 if (fp->f_type != DTYPE_VNODE || fp->f_ops == &path_fileops) { 742 error = EBADF; 743 fdrop(fp, td); 744 break; 745 } 746 flp = (struct flock *)arg; 747 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 748 flp->l_type != F_UNLCK) { 749 error = EINVAL; 750 fdrop(fp, td); 751 break; 752 } 753 if (flp->l_whence == SEEK_CUR) { 754 foffset = foffset_get(fp); 755 if ((flp->l_start > 0 && 756 foffset > OFF_MAX - flp->l_start) || 757 (flp->l_start < 0 && 758 foffset < OFF_MIN - flp->l_start)) { 759 error = EOVERFLOW; 760 fdrop(fp, td); 761 break; 762 } 763 flp->l_start += foffset; 764 } 765 vp = fp->f_vnode; 766 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 767 F_POSIX); 768 fdrop(fp, td); 769 break; 770 771 case F_ADD_SEALS: 772 error = fget_unlocked(td, fd, &cap_no_rights, &fp); 773 if (error != 0) 774 break; 775 error = fo_add_seals(fp, arg); 776 fdrop(fp, td); 777 break; 778 779 case F_GET_SEALS: 780 error = fget_unlocked(td, fd, &cap_no_rights, &fp); 781 if (error != 0) 782 break; 783 if (fo_get_seals(fp, &seals) == 0) 784 td->td_retval[0] = seals; 785 else 786 error = EINVAL; 787 fdrop(fp, td); 788 break; 789 790 case F_RDAHEAD: 791 arg = arg ? 128 * 1024: 0; 792 /* FALLTHROUGH */ 793 case F_READAHEAD: 794 error = fget_unlocked(td, fd, &cap_no_rights, &fp); 795 if (error != 0) 796 break; 797 if (fp->f_type != DTYPE_VNODE || fp->f_ops == &path_fileops) { 798 fdrop(fp, td); 799 error = EBADF; 800 break; 801 } 802 vp = fp->f_vnode; 803 if (vp->v_type != VREG) { 804 fdrop(fp, td); 805 error = ENOTTY; 806 break; 807 } 808 809 /* 810 * Exclusive lock synchronizes against f_seqcount reads and 811 * writes in sequential_heuristic(). 812 */ 813 error = vn_lock(vp, LK_EXCLUSIVE); 814 if (error != 0) { 815 fdrop(fp, td); 816 break; 817 } 818 if (arg >= 0) { 819 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 820 arg = MIN(arg, INT_MAX - bsize + 1); 821 fp->f_seqcount[UIO_READ] = MIN(IO_SEQMAX, 822 (arg + bsize - 1) / bsize); 823 atomic_set_int(&fp->f_flag, FRDAHEAD); 824 } else { 825 atomic_clear_int(&fp->f_flag, FRDAHEAD); 826 } 827 VOP_UNLOCK(vp); 828 fdrop(fp, td); 829 break; 830 831 case F_ISUNIONSTACK: 832 /* 833 * Check if the vnode is part of a union stack (either the 834 * "union" flag from mount(2) or unionfs). 835 * 836 * Prior to introduction of this op libc's readdir would call 837 * fstatfs(2), in effect unnecessarily copying kilobytes of 838 * data just to check fs name and a mount flag. 839 * 840 * Fixing the code to handle everything in the kernel instead 841 * is a non-trivial endeavor and has low priority, thus this 842 * horrible kludge facilitates the current behavior in a much 843 * cheaper manner until someone(tm) sorts this out. 844 */ 845 error = fget_unlocked(td, fd, &cap_no_rights, &fp); 846 if (error != 0) 847 break; 848 if (fp->f_type != DTYPE_VNODE) { 849 fdrop(fp, td); 850 error = EBADF; 851 break; 852 } 853 vp = fp->f_vnode; 854 /* 855 * Since we don't prevent dooming the vnode even non-null mp 856 * found can become immediately stale. This is tolerable since 857 * mount points are type-stable (providing safe memory access) 858 * and any vfs op on this vnode going forward will return an 859 * error (meaning return value in this case is meaningless). 860 */ 861 mp = atomic_load_ptr(&vp->v_mount); 862 if (__predict_false(mp == NULL)) { 863 fdrop(fp, td); 864 error = EBADF; 865 break; 866 } 867 td->td_retval[0] = 0; 868 if (mp->mnt_kern_flag & MNTK_UNIONFS || 869 mp->mnt_flag & MNT_UNION) 870 td->td_retval[0] = 1; 871 fdrop(fp, td); 872 break; 873 874 case F_KINFO: 875 #ifdef CAPABILITY_MODE 876 if (CAP_TRACING(td)) 877 ktrcapfail(CAPFAIL_SYSCALL, &cmd); 878 if (IN_CAPABILITY_MODE(td)) { 879 error = ECAPMODE; 880 break; 881 } 882 #endif 883 error = copyin((void *)arg, &kif_sz, sizeof(kif_sz)); 884 if (error != 0) 885 break; 886 if (kif_sz != sizeof(*kif)) { 887 error = EINVAL; 888 break; 889 } 890 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK | M_ZERO); 891 FILEDESC_SLOCK(fdp); 892 error = fget_cap_noref(fdp, fd, &cap_fcntl_rights, &fp, NULL); 893 if (error == 0 && fhold(fp)) { 894 export_file_to_kinfo(fp, fd, NULL, kif, fdp, 0); 895 FILEDESC_SUNLOCK(fdp); 896 fdrop(fp, td); 897 if ((kif->kf_status & KF_ATTR_VALID) != 0) { 898 kif->kf_structsize = sizeof(*kif); 899 error = copyout(kif, (void *)arg, sizeof(*kif)); 900 } else { 901 error = EBADF; 902 } 903 } else { 904 FILEDESC_SUNLOCK(fdp); 905 if (error == 0) 906 error = EBADF; 907 } 908 free(kif, M_TEMP); 909 break; 910 911 default: 912 error = EINVAL; 913 break; 914 } 915 return (error); 916 } 917 918 static int 919 getmaxfd(struct thread *td) 920 { 921 922 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc)); 923 } 924 925 /* 926 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 927 */ 928 int 929 kern_dup(struct thread *td, u_int mode, int flags, int old, int new) 930 { 931 struct filedesc *fdp; 932 struct filedescent *oldfde, *newfde; 933 struct proc *p; 934 struct file *delfp, *oldfp; 935 u_long *oioctls, *nioctls; 936 int error, maxfd; 937 938 p = td->td_proc; 939 fdp = p->p_fd; 940 oioctls = NULL; 941 942 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0); 943 MPASS(mode < FDDUP_LASTMODE); 944 945 AUDIT_ARG_FD(old); 946 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */ 947 948 /* 949 * Verify we have a valid descriptor to dup from and possibly to 950 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 951 * return EINVAL when the new descriptor is out of bounds. 952 */ 953 if (old < 0) 954 return (EBADF); 955 if (new < 0) 956 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 957 maxfd = getmaxfd(td); 958 if (new >= maxfd) 959 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 960 961 error = EBADF; 962 FILEDESC_XLOCK(fdp); 963 if (fget_noref(fdp, old) == NULL) 964 goto unlock; 965 if (mode == FDDUP_FIXED && old == new) { 966 td->td_retval[0] = new; 967 if (flags & FDDUP_FLAG_CLOEXEC) 968 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 969 error = 0; 970 goto unlock; 971 } 972 973 oldfde = &fdp->fd_ofiles[old]; 974 oldfp = oldfde->fde_file; 975 if (!fhold(oldfp)) 976 goto unlock; 977 978 /* 979 * If the caller specified a file descriptor, make sure the file 980 * table is large enough to hold it, and grab it. Otherwise, just 981 * allocate a new descriptor the usual way. 982 */ 983 switch (mode) { 984 case FDDUP_NORMAL: 985 case FDDUP_FCNTL: 986 if ((error = fdalloc(td, new, &new)) != 0) { 987 fdrop(oldfp, td); 988 goto unlock; 989 } 990 break; 991 case FDDUP_FIXED: 992 if (new >= fdp->fd_nfiles) { 993 /* 994 * The resource limits are here instead of e.g. 995 * fdalloc(), because the file descriptor table may be 996 * shared between processes, so we can't really use 997 * racct_add()/racct_sub(). Instead of counting the 998 * number of actually allocated descriptors, just put 999 * the limit on the size of the file descriptor table. 1000 */ 1001 #ifdef RACCT 1002 if (RACCT_ENABLED()) { 1003 error = racct_set_unlocked(p, RACCT_NOFILE, new + 1); 1004 if (error != 0) { 1005 error = EMFILE; 1006 fdrop(oldfp, td); 1007 goto unlock; 1008 } 1009 } 1010 #endif 1011 fdgrowtable_exp(fdp, new + 1); 1012 } 1013 if (!fdisused(fdp, new)) 1014 fdused(fdp, new); 1015 break; 1016 default: 1017 KASSERT(0, ("%s unsupported mode %d", __func__, mode)); 1018 } 1019 1020 KASSERT(old != new, ("new fd is same as old")); 1021 1022 /* Refetch oldfde because the table may have grown and old one freed. */ 1023 oldfde = &fdp->fd_ofiles[old]; 1024 KASSERT(oldfp == oldfde->fde_file, 1025 ("fdt_ofiles shift from growth observed at fd %d", 1026 old)); 1027 1028 newfde = &fdp->fd_ofiles[new]; 1029 delfp = newfde->fde_file; 1030 1031 nioctls = filecaps_copy_prep(&oldfde->fde_caps); 1032 1033 /* 1034 * Duplicate the source descriptor. 1035 */ 1036 #ifdef CAPABILITIES 1037 seqc_write_begin(&newfde->fde_seqc); 1038 #endif 1039 oioctls = filecaps_free_prep(&newfde->fde_caps); 1040 fde_copy(oldfde, newfde); 1041 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps, 1042 nioctls); 1043 if ((flags & FDDUP_FLAG_CLOEXEC) != 0) 1044 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 1045 else 1046 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 1047 #ifdef CAPABILITIES 1048 seqc_write_end(&newfde->fde_seqc); 1049 #endif 1050 td->td_retval[0] = new; 1051 1052 error = 0; 1053 1054 if (delfp != NULL) { 1055 (void) closefp(fdp, new, delfp, td, true, false); 1056 FILEDESC_UNLOCK_ASSERT(fdp); 1057 } else { 1058 unlock: 1059 FILEDESC_XUNLOCK(fdp); 1060 } 1061 1062 filecaps_free_finish(oioctls); 1063 return (error); 1064 } 1065 1066 static void 1067 sigiofree(struct sigio *sigio) 1068 { 1069 crfree(sigio->sio_ucred); 1070 free(sigio, M_SIGIO); 1071 } 1072 1073 static struct sigio * 1074 funsetown_locked(struct sigio *sigio) 1075 { 1076 struct proc *p; 1077 struct pgrp *pg; 1078 1079 SIGIO_ASSERT_LOCKED(); 1080 1081 if (sigio == NULL) 1082 return (NULL); 1083 *sigio->sio_myref = NULL; 1084 if (sigio->sio_pgid < 0) { 1085 pg = sigio->sio_pgrp; 1086 PGRP_LOCK(pg); 1087 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, sio_pgsigio); 1088 PGRP_UNLOCK(pg); 1089 } else { 1090 p = sigio->sio_proc; 1091 PROC_LOCK(p); 1092 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, sio_pgsigio); 1093 PROC_UNLOCK(p); 1094 } 1095 return (sigio); 1096 } 1097 1098 /* 1099 * If sigio is on the list associated with a process or process group, 1100 * disable signalling from the device, remove sigio from the list and 1101 * free sigio. 1102 */ 1103 void 1104 funsetown(struct sigio **sigiop) 1105 { 1106 struct sigio *sigio; 1107 1108 /* Racy check, consumers must provide synchronization. */ 1109 if (*sigiop == NULL) 1110 return; 1111 1112 SIGIO_LOCK(); 1113 sigio = funsetown_locked(*sigiop); 1114 SIGIO_UNLOCK(); 1115 if (sigio != NULL) 1116 sigiofree(sigio); 1117 } 1118 1119 /* 1120 * Free a list of sigio structures. The caller must ensure that new sigio 1121 * structures cannot be added after this point. For process groups this is 1122 * guaranteed using the proctree lock; for processes, the P_WEXIT flag serves 1123 * as an interlock. 1124 */ 1125 void 1126 funsetownlst(struct sigiolst *sigiolst) 1127 { 1128 struct proc *p; 1129 struct pgrp *pg; 1130 struct sigio *sigio, *tmp; 1131 1132 /* Racy check. */ 1133 sigio = SLIST_FIRST(sigiolst); 1134 if (sigio == NULL) 1135 return; 1136 1137 p = NULL; 1138 pg = NULL; 1139 1140 SIGIO_LOCK(); 1141 sigio = SLIST_FIRST(sigiolst); 1142 if (sigio == NULL) { 1143 SIGIO_UNLOCK(); 1144 return; 1145 } 1146 1147 /* 1148 * Every entry of the list should belong to a single proc or pgrp. 1149 */ 1150 if (sigio->sio_pgid < 0) { 1151 pg = sigio->sio_pgrp; 1152 sx_assert(&proctree_lock, SX_XLOCKED); 1153 PGRP_LOCK(pg); 1154 } else /* if (sigio->sio_pgid > 0) */ { 1155 p = sigio->sio_proc; 1156 PROC_LOCK(p); 1157 KASSERT((p->p_flag & P_WEXIT) != 0, 1158 ("%s: process %p is not exiting", __func__, p)); 1159 } 1160 1161 SLIST_FOREACH(sigio, sigiolst, sio_pgsigio) { 1162 *sigio->sio_myref = NULL; 1163 if (pg != NULL) { 1164 KASSERT(sigio->sio_pgid < 0, 1165 ("Proc sigio in pgrp sigio list")); 1166 KASSERT(sigio->sio_pgrp == pg, 1167 ("Bogus pgrp in sigio list")); 1168 } else /* if (p != NULL) */ { 1169 KASSERT(sigio->sio_pgid > 0, 1170 ("Pgrp sigio in proc sigio list")); 1171 KASSERT(sigio->sio_proc == p, 1172 ("Bogus proc in sigio list")); 1173 } 1174 } 1175 1176 if (pg != NULL) 1177 PGRP_UNLOCK(pg); 1178 else 1179 PROC_UNLOCK(p); 1180 SIGIO_UNLOCK(); 1181 1182 SLIST_FOREACH_SAFE(sigio, sigiolst, sio_pgsigio, tmp) 1183 sigiofree(sigio); 1184 } 1185 1186 /* 1187 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1188 * 1189 * After permission checking, add a sigio structure to the sigio list for 1190 * the process or process group. 1191 */ 1192 int 1193 fsetown(pid_t pgid, struct sigio **sigiop) 1194 { 1195 struct proc *proc; 1196 struct pgrp *pgrp; 1197 struct sigio *osigio, *sigio; 1198 int ret; 1199 1200 if (pgid == 0) { 1201 funsetown(sigiop); 1202 return (0); 1203 } 1204 1205 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1206 sigio->sio_pgid = pgid; 1207 sigio->sio_ucred = crhold(curthread->td_ucred); 1208 sigio->sio_myref = sigiop; 1209 1210 ret = 0; 1211 if (pgid > 0) { 1212 ret = pget(pgid, PGET_NOTWEXIT | PGET_NOTID | PGET_HOLD, &proc); 1213 SIGIO_LOCK(); 1214 osigio = funsetown_locked(*sigiop); 1215 if (ret == 0) { 1216 PROC_LOCK(proc); 1217 _PRELE(proc); 1218 if ((proc->p_flag & P_WEXIT) != 0) { 1219 ret = ESRCH; 1220 } else if (proc->p_session != 1221 curthread->td_proc->p_session) { 1222 /* 1223 * Policy - Don't allow a process to FSETOWN a 1224 * process in another session. 1225 * 1226 * Remove this test to allow maximum flexibility 1227 * or restrict FSETOWN to the current process or 1228 * process group for maximum safety. 1229 */ 1230 ret = EPERM; 1231 } else { 1232 sigio->sio_proc = proc; 1233 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, 1234 sio_pgsigio); 1235 } 1236 PROC_UNLOCK(proc); 1237 } 1238 } else /* if (pgid < 0) */ { 1239 sx_slock(&proctree_lock); 1240 SIGIO_LOCK(); 1241 osigio = funsetown_locked(*sigiop); 1242 pgrp = pgfind(-pgid); 1243 if (pgrp == NULL) { 1244 ret = ESRCH; 1245 } else { 1246 if (pgrp->pg_session != curthread->td_proc->p_session) { 1247 /* 1248 * Policy - Don't allow a process to FSETOWN a 1249 * process in another session. 1250 * 1251 * Remove this test to allow maximum flexibility 1252 * or restrict FSETOWN to the current process or 1253 * process group for maximum safety. 1254 */ 1255 ret = EPERM; 1256 } else { 1257 sigio->sio_pgrp = pgrp; 1258 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, 1259 sio_pgsigio); 1260 } 1261 PGRP_UNLOCK(pgrp); 1262 } 1263 sx_sunlock(&proctree_lock); 1264 } 1265 if (ret == 0) 1266 *sigiop = sigio; 1267 SIGIO_UNLOCK(); 1268 if (osigio != NULL) 1269 sigiofree(osigio); 1270 return (ret); 1271 } 1272 1273 /* 1274 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1275 */ 1276 pid_t 1277 fgetown(struct sigio **sigiop) 1278 { 1279 pid_t pgid; 1280 1281 SIGIO_LOCK(); 1282 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1283 SIGIO_UNLOCK(); 1284 return (pgid); 1285 } 1286 1287 static int 1288 closefp_impl(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1289 bool audit) 1290 { 1291 int error; 1292 1293 FILEDESC_XLOCK_ASSERT(fdp); 1294 1295 /* 1296 * We now hold the fp reference that used to be owned by the 1297 * descriptor array. We have to unlock the FILEDESC *AFTER* 1298 * knote_fdclose to prevent a race of the fd getting opened, a knote 1299 * added, and deleteing a knote for the new fd. 1300 */ 1301 if (__predict_false(!TAILQ_EMPTY(&fdp->fd_kqlist))) 1302 knote_fdclose(td, fd); 1303 1304 /* 1305 * We need to notify mqueue if the object is of type mqueue. 1306 */ 1307 if (__predict_false(fp->f_type == DTYPE_MQUEUE)) 1308 mq_fdclose(td, fd, fp); 1309 FILEDESC_XUNLOCK(fdp); 1310 1311 #ifdef AUDIT 1312 if (AUDITING_TD(td) && audit) 1313 audit_sysclose(td, fd, fp); 1314 #endif 1315 error = closef(fp, td); 1316 1317 /* 1318 * All paths leading up to closefp() will have already removed or 1319 * replaced the fd in the filedesc table, so a restart would not 1320 * operate on the same file. 1321 */ 1322 if (error == ERESTART) 1323 error = EINTR; 1324 1325 return (error); 1326 } 1327 1328 static int 1329 closefp_hl(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1330 bool holdleaders, bool audit) 1331 { 1332 int error; 1333 1334 FILEDESC_XLOCK_ASSERT(fdp); 1335 1336 if (holdleaders) { 1337 if (td->td_proc->p_fdtol != NULL) { 1338 /* 1339 * Ask fdfree() to sleep to ensure that all relevant 1340 * process leaders can be traversed in closef(). 1341 */ 1342 fdp->fd_holdleaderscount++; 1343 } else { 1344 holdleaders = false; 1345 } 1346 } 1347 1348 error = closefp_impl(fdp, fd, fp, td, audit); 1349 if (holdleaders) { 1350 FILEDESC_XLOCK(fdp); 1351 fdp->fd_holdleaderscount--; 1352 if (fdp->fd_holdleaderscount == 0 && 1353 fdp->fd_holdleaderswakeup != 0) { 1354 fdp->fd_holdleaderswakeup = 0; 1355 wakeup(&fdp->fd_holdleaderscount); 1356 } 1357 FILEDESC_XUNLOCK(fdp); 1358 } 1359 return (error); 1360 } 1361 1362 static int 1363 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1364 bool holdleaders, bool audit) 1365 { 1366 1367 FILEDESC_XLOCK_ASSERT(fdp); 1368 1369 if (__predict_false(td->td_proc->p_fdtol != NULL)) { 1370 return (closefp_hl(fdp, fd, fp, td, holdleaders, audit)); 1371 } else { 1372 return (closefp_impl(fdp, fd, fp, td, audit)); 1373 } 1374 } 1375 1376 /* 1377 * Close a file descriptor. 1378 */ 1379 #ifndef _SYS_SYSPROTO_H_ 1380 struct close_args { 1381 int fd; 1382 }; 1383 #endif 1384 /* ARGSUSED */ 1385 int 1386 sys_close(struct thread *td, struct close_args *uap) 1387 { 1388 1389 return (kern_close(td, uap->fd)); 1390 } 1391 1392 int 1393 kern_close(struct thread *td, int fd) 1394 { 1395 struct filedesc *fdp; 1396 struct file *fp; 1397 1398 fdp = td->td_proc->p_fd; 1399 1400 FILEDESC_XLOCK(fdp); 1401 if ((fp = fget_noref(fdp, fd)) == NULL) { 1402 FILEDESC_XUNLOCK(fdp); 1403 return (EBADF); 1404 } 1405 fdfree(fdp, fd); 1406 1407 /* closefp() drops the FILEDESC lock for us. */ 1408 return (closefp(fdp, fd, fp, td, true, true)); 1409 } 1410 1411 static int 1412 close_range_cloexec(struct thread *td, u_int lowfd, u_int highfd) 1413 { 1414 struct filedesc *fdp; 1415 struct fdescenttbl *fdt; 1416 struct filedescent *fde; 1417 int fd; 1418 1419 fdp = td->td_proc->p_fd; 1420 FILEDESC_XLOCK(fdp); 1421 fdt = atomic_load_ptr(&fdp->fd_files); 1422 highfd = MIN(highfd, fdt->fdt_nfiles - 1); 1423 fd = lowfd; 1424 if (__predict_false(fd > highfd)) { 1425 goto out_locked; 1426 } 1427 for (; fd <= highfd; fd++) { 1428 fde = &fdt->fdt_ofiles[fd]; 1429 if (fde->fde_file != NULL) 1430 fde->fde_flags |= UF_EXCLOSE; 1431 } 1432 out_locked: 1433 FILEDESC_XUNLOCK(fdp); 1434 return (0); 1435 } 1436 1437 static int 1438 close_range_impl(struct thread *td, u_int lowfd, u_int highfd) 1439 { 1440 struct filedesc *fdp; 1441 const struct fdescenttbl *fdt; 1442 struct file *fp; 1443 int fd; 1444 1445 fdp = td->td_proc->p_fd; 1446 FILEDESC_XLOCK(fdp); 1447 fdt = atomic_load_ptr(&fdp->fd_files); 1448 highfd = MIN(highfd, fdt->fdt_nfiles - 1); 1449 fd = lowfd; 1450 if (__predict_false(fd > highfd)) { 1451 goto out_locked; 1452 } 1453 for (;;) { 1454 fp = fdt->fdt_ofiles[fd].fde_file; 1455 if (fp == NULL) { 1456 if (fd == highfd) 1457 goto out_locked; 1458 } else { 1459 fdfree(fdp, fd); 1460 (void) closefp(fdp, fd, fp, td, true, true); 1461 if (fd == highfd) 1462 goto out_unlocked; 1463 FILEDESC_XLOCK(fdp); 1464 fdt = atomic_load_ptr(&fdp->fd_files); 1465 } 1466 fd++; 1467 } 1468 out_locked: 1469 FILEDESC_XUNLOCK(fdp); 1470 out_unlocked: 1471 return (0); 1472 } 1473 1474 int 1475 kern_close_range(struct thread *td, int flags, u_int lowfd, u_int highfd) 1476 { 1477 1478 /* 1479 * Check this prior to clamping; closefrom(3) with only fd 0, 1, and 2 1480 * open should not be a usage error. From a close_range() perspective, 1481 * close_range(3, ~0U, 0) in the same scenario should also likely not 1482 * be a usage error as all fd above 3 are in-fact already closed. 1483 */ 1484 if (highfd < lowfd) { 1485 return (EINVAL); 1486 } 1487 1488 if ((flags & CLOSE_RANGE_CLOEXEC) != 0) 1489 return (close_range_cloexec(td, lowfd, highfd)); 1490 1491 return (close_range_impl(td, lowfd, highfd)); 1492 } 1493 1494 #ifndef _SYS_SYSPROTO_H_ 1495 struct close_range_args { 1496 u_int lowfd; 1497 u_int highfd; 1498 int flags; 1499 }; 1500 #endif 1501 int 1502 sys_close_range(struct thread *td, struct close_range_args *uap) 1503 { 1504 1505 AUDIT_ARG_FD(uap->lowfd); 1506 AUDIT_ARG_CMD(uap->highfd); 1507 AUDIT_ARG_FFLAGS(uap->flags); 1508 1509 if ((uap->flags & ~(CLOSE_RANGE_CLOEXEC)) != 0) 1510 return (EINVAL); 1511 return (kern_close_range(td, uap->flags, uap->lowfd, uap->highfd)); 1512 } 1513 1514 #ifdef COMPAT_FREEBSD12 1515 /* 1516 * Close open file descriptors. 1517 */ 1518 #ifndef _SYS_SYSPROTO_H_ 1519 struct freebsd12_closefrom_args { 1520 int lowfd; 1521 }; 1522 #endif 1523 /* ARGSUSED */ 1524 int 1525 freebsd12_closefrom(struct thread *td, struct freebsd12_closefrom_args *uap) 1526 { 1527 u_int lowfd; 1528 1529 AUDIT_ARG_FD(uap->lowfd); 1530 1531 /* 1532 * Treat negative starting file descriptor values identical to 1533 * closefrom(0) which closes all files. 1534 */ 1535 lowfd = MAX(0, uap->lowfd); 1536 return (kern_close_range(td, 0, lowfd, ~0U)); 1537 } 1538 #endif /* COMPAT_FREEBSD12 */ 1539 1540 #if defined(COMPAT_43) 1541 /* 1542 * Return status information about a file descriptor. 1543 */ 1544 #ifndef _SYS_SYSPROTO_H_ 1545 struct ofstat_args { 1546 int fd; 1547 struct ostat *sb; 1548 }; 1549 #endif 1550 /* ARGSUSED */ 1551 int 1552 ofstat(struct thread *td, struct ofstat_args *uap) 1553 { 1554 struct ostat oub; 1555 struct stat ub; 1556 int error; 1557 1558 error = kern_fstat(td, uap->fd, &ub); 1559 if (error == 0) { 1560 cvtstat(&ub, &oub); 1561 error = copyout(&oub, uap->sb, sizeof(oub)); 1562 } 1563 return (error); 1564 } 1565 #endif /* COMPAT_43 */ 1566 1567 #if defined(COMPAT_FREEBSD11) 1568 int 1569 freebsd11_fstat(struct thread *td, struct freebsd11_fstat_args *uap) 1570 { 1571 struct stat sb; 1572 struct freebsd11_stat osb; 1573 int error; 1574 1575 error = kern_fstat(td, uap->fd, &sb); 1576 if (error != 0) 1577 return (error); 1578 error = freebsd11_cvtstat(&sb, &osb); 1579 if (error == 0) 1580 error = copyout(&osb, uap->sb, sizeof(osb)); 1581 return (error); 1582 } 1583 #endif /* COMPAT_FREEBSD11 */ 1584 1585 /* 1586 * Return status information about a file descriptor. 1587 */ 1588 #ifndef _SYS_SYSPROTO_H_ 1589 struct fstat_args { 1590 int fd; 1591 struct stat *sb; 1592 }; 1593 #endif 1594 /* ARGSUSED */ 1595 int 1596 sys_fstat(struct thread *td, struct fstat_args *uap) 1597 { 1598 struct stat ub; 1599 int error; 1600 1601 error = kern_fstat(td, uap->fd, &ub); 1602 if (error == 0) 1603 error = copyout(&ub, uap->sb, sizeof(ub)); 1604 return (error); 1605 } 1606 1607 int 1608 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1609 { 1610 struct file *fp; 1611 int error; 1612 1613 AUDIT_ARG_FD(fd); 1614 1615 error = fget(td, fd, &cap_fstat_rights, &fp); 1616 if (__predict_false(error != 0)) 1617 return (error); 1618 1619 AUDIT_ARG_FILE(td->td_proc, fp); 1620 1621 sbp->st_filerev = 0; 1622 sbp->st_bsdflags = 0; 1623 error = fo_stat(fp, sbp, td->td_ucred); 1624 fdrop(fp, td); 1625 #ifdef __STAT_TIME_T_EXT 1626 sbp->st_atim_ext = 0; 1627 sbp->st_mtim_ext = 0; 1628 sbp->st_ctim_ext = 0; 1629 sbp->st_btim_ext = 0; 1630 #endif 1631 #ifdef KTRACE 1632 if (KTRPOINT(td, KTR_STRUCT)) 1633 ktrstat_error(sbp, error); 1634 #endif 1635 return (error); 1636 } 1637 1638 #if defined(COMPAT_FREEBSD11) 1639 /* 1640 * Return status information about a file descriptor. 1641 */ 1642 #ifndef _SYS_SYSPROTO_H_ 1643 struct freebsd11_nfstat_args { 1644 int fd; 1645 struct nstat *sb; 1646 }; 1647 #endif 1648 /* ARGSUSED */ 1649 int 1650 freebsd11_nfstat(struct thread *td, struct freebsd11_nfstat_args *uap) 1651 { 1652 struct nstat nub; 1653 struct stat ub; 1654 int error; 1655 1656 error = kern_fstat(td, uap->fd, &ub); 1657 if (error != 0) 1658 return (error); 1659 error = freebsd11_cvtnstat(&ub, &nub); 1660 if (error != 0) 1661 error = copyout(&nub, uap->sb, sizeof(nub)); 1662 return (error); 1663 } 1664 #endif /* COMPAT_FREEBSD11 */ 1665 1666 /* 1667 * Return pathconf information about a file descriptor. 1668 */ 1669 #ifndef _SYS_SYSPROTO_H_ 1670 struct fpathconf_args { 1671 int fd; 1672 int name; 1673 }; 1674 #endif 1675 /* ARGSUSED */ 1676 int 1677 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1678 { 1679 long value; 1680 int error; 1681 1682 error = kern_fpathconf(td, uap->fd, uap->name, &value); 1683 if (error == 0) 1684 td->td_retval[0] = value; 1685 return (error); 1686 } 1687 1688 int 1689 kern_fpathconf(struct thread *td, int fd, int name, long *valuep) 1690 { 1691 struct file *fp; 1692 struct vnode *vp; 1693 int error; 1694 1695 error = fget(td, fd, &cap_fpathconf_rights, &fp); 1696 if (error != 0) 1697 return (error); 1698 1699 if (name == _PC_ASYNC_IO) { 1700 *valuep = _POSIX_ASYNCHRONOUS_IO; 1701 goto out; 1702 } 1703 vp = fp->f_vnode; 1704 if (vp != NULL) { 1705 vn_lock(vp, LK_SHARED | LK_RETRY); 1706 error = VOP_PATHCONF(vp, name, valuep); 1707 VOP_UNLOCK(vp); 1708 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1709 if (name != _PC_PIPE_BUF) { 1710 error = EINVAL; 1711 } else { 1712 *valuep = PIPE_BUF; 1713 error = 0; 1714 } 1715 } else { 1716 error = EOPNOTSUPP; 1717 } 1718 out: 1719 fdrop(fp, td); 1720 return (error); 1721 } 1722 1723 /* 1724 * Copy filecaps structure allocating memory for ioctls array if needed. 1725 * 1726 * The last parameter indicates whether the fdtable is locked. If it is not and 1727 * ioctls are encountered, copying fails and the caller must lock the table. 1728 * 1729 * Note that if the table was not locked, the caller has to check the relevant 1730 * sequence counter to determine whether the operation was successful. 1731 */ 1732 bool 1733 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked) 1734 { 1735 size_t size; 1736 1737 if (src->fc_ioctls != NULL && !locked) 1738 return (false); 1739 memcpy(dst, src, sizeof(*src)); 1740 if (src->fc_ioctls == NULL) 1741 return (true); 1742 1743 KASSERT(src->fc_nioctls > 0, 1744 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1745 1746 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1747 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1748 memcpy(dst->fc_ioctls, src->fc_ioctls, size); 1749 return (true); 1750 } 1751 1752 static u_long * 1753 filecaps_copy_prep(const struct filecaps *src) 1754 { 1755 u_long *ioctls; 1756 size_t size; 1757 1758 if (__predict_true(src->fc_ioctls == NULL)) 1759 return (NULL); 1760 1761 KASSERT(src->fc_nioctls > 0, 1762 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1763 1764 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1765 ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1766 return (ioctls); 1767 } 1768 1769 static void 1770 filecaps_copy_finish(const struct filecaps *src, struct filecaps *dst, 1771 u_long *ioctls) 1772 { 1773 size_t size; 1774 1775 *dst = *src; 1776 if (__predict_true(src->fc_ioctls == NULL)) { 1777 MPASS(ioctls == NULL); 1778 return; 1779 } 1780 1781 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1782 dst->fc_ioctls = ioctls; 1783 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1784 } 1785 1786 /* 1787 * Move filecaps structure to the new place and clear the old place. 1788 */ 1789 void 1790 filecaps_move(struct filecaps *src, struct filecaps *dst) 1791 { 1792 1793 *dst = *src; 1794 bzero(src, sizeof(*src)); 1795 } 1796 1797 /* 1798 * Fill the given filecaps structure with full rights. 1799 */ 1800 static void 1801 filecaps_fill(struct filecaps *fcaps) 1802 { 1803 1804 CAP_ALL(&fcaps->fc_rights); 1805 fcaps->fc_ioctls = NULL; 1806 fcaps->fc_nioctls = -1; 1807 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1808 } 1809 1810 /* 1811 * Free memory allocated within filecaps structure. 1812 */ 1813 static void 1814 filecaps_free_ioctl(struct filecaps *fcaps) 1815 { 1816 1817 free(fcaps->fc_ioctls, M_FILECAPS); 1818 fcaps->fc_ioctls = NULL; 1819 } 1820 1821 void 1822 filecaps_free(struct filecaps *fcaps) 1823 { 1824 1825 filecaps_free_ioctl(fcaps); 1826 bzero(fcaps, sizeof(*fcaps)); 1827 } 1828 1829 static u_long * 1830 filecaps_free_prep(struct filecaps *fcaps) 1831 { 1832 u_long *ioctls; 1833 1834 ioctls = fcaps->fc_ioctls; 1835 bzero(fcaps, sizeof(*fcaps)); 1836 return (ioctls); 1837 } 1838 1839 static void 1840 filecaps_free_finish(u_long *ioctls) 1841 { 1842 1843 free(ioctls, M_FILECAPS); 1844 } 1845 1846 /* 1847 * Validate the given filecaps structure. 1848 */ 1849 static void 1850 filecaps_validate(const struct filecaps *fcaps, const char *func) 1851 { 1852 1853 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1854 ("%s: invalid rights", func)); 1855 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1856 ("%s: invalid fcntls", func)); 1857 KASSERT(fcaps->fc_fcntls == 0 || 1858 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1859 ("%s: fcntls without CAP_FCNTL", func)); 1860 /* 1861 * open calls without WANTIOCTLCAPS free caps but leave the counter 1862 */ 1863 #if 0 1864 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1865 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1866 ("%s: invalid ioctls", func)); 1867 #endif 1868 KASSERT(fcaps->fc_nioctls == 0 || 1869 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1870 ("%s: ioctls without CAP_IOCTL", func)); 1871 } 1872 1873 static void 1874 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1875 { 1876 int nfd1; 1877 1878 FILEDESC_XLOCK_ASSERT(fdp); 1879 1880 nfd1 = fdp->fd_nfiles * 2; 1881 if (nfd1 < nfd) 1882 nfd1 = nfd; 1883 fdgrowtable(fdp, nfd1); 1884 } 1885 1886 /* 1887 * Grow the file table to accommodate (at least) nfd descriptors. 1888 */ 1889 static void 1890 fdgrowtable(struct filedesc *fdp, int nfd) 1891 { 1892 struct filedesc0 *fdp0; 1893 struct freetable *ft; 1894 struct fdescenttbl *ntable; 1895 struct fdescenttbl *otable; 1896 int nnfiles, onfiles; 1897 NDSLOTTYPE *nmap, *omap; 1898 1899 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1900 1901 /* save old values */ 1902 onfiles = fdp->fd_nfiles; 1903 otable = fdp->fd_files; 1904 omap = fdp->fd_map; 1905 1906 /* compute the size of the new table */ 1907 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1908 if (nnfiles <= onfiles) 1909 /* the table is already large enough */ 1910 return; 1911 1912 /* 1913 * Allocate a new table. We need enough space for the number of 1914 * entries, file entries themselves and the struct freetable we will use 1915 * when we decommission the table and place it on the freelist. 1916 * We place the struct freetable in the middle so we don't have 1917 * to worry about padding. 1918 */ 1919 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) + 1920 nnfiles * sizeof(ntable->fdt_ofiles[0]) + 1921 sizeof(struct freetable), 1922 M_FILEDESC, M_ZERO | M_WAITOK); 1923 /* copy the old data */ 1924 ntable->fdt_nfiles = nnfiles; 1925 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles, 1926 onfiles * sizeof(ntable->fdt_ofiles[0])); 1927 1928 /* 1929 * Allocate a new map only if the old is not large enough. It will 1930 * grow at a slower rate than the table as it can map more 1931 * entries than the table can hold. 1932 */ 1933 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1934 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1935 M_ZERO | M_WAITOK); 1936 /* copy over the old data and update the pointer */ 1937 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1938 fdp->fd_map = nmap; 1939 } 1940 1941 /* 1942 * Make sure that ntable is correctly initialized before we replace 1943 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent 1944 * data. 1945 */ 1946 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable); 1947 1948 /* 1949 * Free the old file table when not shared by other threads or processes. 1950 * The old file table is considered to be shared when either are true: 1951 * - The process has more than one thread. 1952 * - The file descriptor table has been shared via fdshare(). 1953 * 1954 * When shared, the old file table will be placed on a freelist 1955 * which will be processed when the struct filedesc is released. 1956 * 1957 * Note that if onfiles == NDFILE, we're dealing with the original 1958 * static allocation contained within (struct filedesc0 *)fdp, 1959 * which must not be freed. 1960 */ 1961 if (onfiles > NDFILE) { 1962 /* 1963 * Note we may be called here from fdinit while allocating a 1964 * table for a new process in which case ->p_fd points 1965 * elsewhere. 1966 */ 1967 if (curproc->p_fd != fdp || FILEDESC_IS_ONLY_USER(fdp)) { 1968 free(otable, M_FILEDESC); 1969 } else { 1970 ft = (struct freetable *)&otable->fdt_ofiles[onfiles]; 1971 fdp0 = (struct filedesc0 *)fdp; 1972 ft->ft_table = otable; 1973 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1974 } 1975 } 1976 /* 1977 * The map does not have the same possibility of threads still 1978 * holding references to it. So always free it as long as it 1979 * does not reference the original static allocation. 1980 */ 1981 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1982 free(omap, M_FILEDESC); 1983 } 1984 1985 /* 1986 * Allocate a file descriptor for the process. 1987 */ 1988 int 1989 fdalloc(struct thread *td, int minfd, int *result) 1990 { 1991 struct proc *p = td->td_proc; 1992 struct filedesc *fdp = p->p_fd; 1993 int fd, maxfd, allocfd; 1994 #ifdef RACCT 1995 int error; 1996 #endif 1997 1998 FILEDESC_XLOCK_ASSERT(fdp); 1999 2000 if (fdp->fd_freefile > minfd) 2001 minfd = fdp->fd_freefile; 2002 2003 maxfd = getmaxfd(td); 2004 2005 /* 2006 * Search the bitmap for a free descriptor starting at minfd. 2007 * If none is found, grow the file table. 2008 */ 2009 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 2010 if (__predict_false(fd >= maxfd)) 2011 return (EMFILE); 2012 if (__predict_false(fd >= fdp->fd_nfiles)) { 2013 allocfd = min(fd * 2, maxfd); 2014 #ifdef RACCT 2015 if (RACCT_ENABLED()) { 2016 error = racct_set_unlocked(p, RACCT_NOFILE, allocfd); 2017 if (error != 0) 2018 return (EMFILE); 2019 } 2020 #endif 2021 /* 2022 * fd is already equal to first free descriptor >= minfd, so 2023 * we only need to grow the table and we are done. 2024 */ 2025 fdgrowtable_exp(fdp, allocfd); 2026 } 2027 2028 /* 2029 * Perform some sanity checks, then mark the file descriptor as 2030 * used and return it to the caller. 2031 */ 2032 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 2033 ("invalid descriptor %d", fd)); 2034 KASSERT(!fdisused(fdp, fd), 2035 ("fd_first_free() returned non-free descriptor")); 2036 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 2037 ("file descriptor isn't free")); 2038 fdused(fdp, fd); 2039 *result = fd; 2040 return (0); 2041 } 2042 2043 /* 2044 * Allocate n file descriptors for the process. 2045 */ 2046 int 2047 fdallocn(struct thread *td, int minfd, int *fds, int n) 2048 { 2049 struct proc *p = td->td_proc; 2050 struct filedesc *fdp = p->p_fd; 2051 int i; 2052 2053 FILEDESC_XLOCK_ASSERT(fdp); 2054 2055 for (i = 0; i < n; i++) 2056 if (fdalloc(td, 0, &fds[i]) != 0) 2057 break; 2058 2059 if (i < n) { 2060 for (i--; i >= 0; i--) 2061 fdunused(fdp, fds[i]); 2062 return (EMFILE); 2063 } 2064 2065 return (0); 2066 } 2067 2068 /* 2069 * Create a new open file structure and allocate a file descriptor for the 2070 * process that refers to it. We add one reference to the file for the 2071 * descriptor table and one reference for resultfp. This is to prevent us 2072 * being preempted and the entry in the descriptor table closed after we 2073 * release the FILEDESC lock. 2074 */ 2075 int 2076 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags, 2077 struct filecaps *fcaps) 2078 { 2079 struct file *fp; 2080 int error, fd; 2081 2082 MPASS(resultfp != NULL); 2083 MPASS(resultfd != NULL); 2084 2085 error = _falloc_noinstall(td, &fp, 2); 2086 if (__predict_false(error != 0)) { 2087 return (error); 2088 } 2089 2090 error = finstall_refed(td, fp, &fd, flags, fcaps); 2091 if (__predict_false(error != 0)) { 2092 falloc_abort(td, fp); 2093 return (error); 2094 } 2095 2096 *resultfp = fp; 2097 *resultfd = fd; 2098 2099 return (0); 2100 } 2101 2102 /* 2103 * Create a new open file structure without allocating a file descriptor. 2104 */ 2105 int 2106 _falloc_noinstall(struct thread *td, struct file **resultfp, u_int n) 2107 { 2108 struct file *fp; 2109 int maxuserfiles = maxfiles - (maxfiles / 20); 2110 int openfiles_new; 2111 static struct timeval lastfail; 2112 static int curfail; 2113 2114 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 2115 MPASS(n > 0); 2116 2117 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1; 2118 if ((openfiles_new >= maxuserfiles && 2119 priv_check(td, PRIV_MAXFILES) != 0) || 2120 openfiles_new >= maxfiles) { 2121 atomic_subtract_int(&openfiles, 1); 2122 if (ppsratecheck(&lastfail, &curfail, 1)) { 2123 printf("kern.maxfiles limit exceeded by uid %i, (%s) " 2124 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm); 2125 } 2126 return (ENFILE); 2127 } 2128 fp = uma_zalloc(file_zone, M_WAITOK); 2129 bzero(fp, sizeof(*fp)); 2130 refcount_init(&fp->f_count, n); 2131 fp->f_cred = crhold(td->td_ucred); 2132 fp->f_ops = &badfileops; 2133 *resultfp = fp; 2134 return (0); 2135 } 2136 2137 void 2138 falloc_abort(struct thread *td, struct file *fp) 2139 { 2140 2141 /* 2142 * For assertion purposes. 2143 */ 2144 refcount_init(&fp->f_count, 0); 2145 _fdrop(fp, td); 2146 } 2147 2148 /* 2149 * Install a file in a file descriptor table. 2150 */ 2151 void 2152 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags, 2153 struct filecaps *fcaps) 2154 { 2155 struct filedescent *fde; 2156 2157 MPASS(fp != NULL); 2158 if (fcaps != NULL) 2159 filecaps_validate(fcaps, __func__); 2160 FILEDESC_XLOCK_ASSERT(fdp); 2161 2162 fde = &fdp->fd_ofiles[fd]; 2163 #ifdef CAPABILITIES 2164 seqc_write_begin(&fde->fde_seqc); 2165 #endif 2166 fde->fde_file = fp; 2167 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0; 2168 if (fcaps != NULL) 2169 filecaps_move(fcaps, &fde->fde_caps); 2170 else 2171 filecaps_fill(&fde->fde_caps); 2172 #ifdef CAPABILITIES 2173 seqc_write_end(&fde->fde_seqc); 2174 #endif 2175 } 2176 2177 int 2178 finstall_refed(struct thread *td, struct file *fp, int *fd, int flags, 2179 struct filecaps *fcaps) 2180 { 2181 struct filedesc *fdp = td->td_proc->p_fd; 2182 int error; 2183 2184 MPASS(fd != NULL); 2185 2186 FILEDESC_XLOCK(fdp); 2187 error = fdalloc(td, 0, fd); 2188 if (__predict_true(error == 0)) { 2189 _finstall(fdp, fp, *fd, flags, fcaps); 2190 } 2191 FILEDESC_XUNLOCK(fdp); 2192 return (error); 2193 } 2194 2195 int 2196 finstall(struct thread *td, struct file *fp, int *fd, int flags, 2197 struct filecaps *fcaps) 2198 { 2199 int error; 2200 2201 MPASS(fd != NULL); 2202 2203 if (!fhold(fp)) 2204 return (EBADF); 2205 error = finstall_refed(td, fp, fd, flags, fcaps); 2206 if (__predict_false(error != 0)) { 2207 fdrop(fp, td); 2208 } 2209 return (error); 2210 } 2211 2212 /* 2213 * Build a new filedesc structure from another. 2214 * 2215 * If fdp is not NULL, return with it shared locked. 2216 */ 2217 struct filedesc * 2218 fdinit(void) 2219 { 2220 struct filedesc0 *newfdp0; 2221 struct filedesc *newfdp; 2222 2223 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO); 2224 newfdp = &newfdp0->fd_fd; 2225 2226 /* Create the file descriptor table. */ 2227 FILEDESC_LOCK_INIT(newfdp); 2228 refcount_init(&newfdp->fd_refcnt, 1); 2229 refcount_init(&newfdp->fd_holdcnt, 1); 2230 newfdp->fd_map = newfdp0->fd_dmap; 2231 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles; 2232 newfdp->fd_files->fdt_nfiles = NDFILE; 2233 2234 return (newfdp); 2235 } 2236 2237 /* 2238 * Build a pwddesc structure from another. 2239 * Copy the current, root, and jail root vnode references. 2240 * 2241 * If pdp is not NULL and keeplock is true, return with it (exclusively) locked. 2242 */ 2243 struct pwddesc * 2244 pdinit(struct pwddesc *pdp, bool keeplock) 2245 { 2246 struct pwddesc *newpdp; 2247 struct pwd *newpwd; 2248 2249 newpdp = malloc(sizeof(*newpdp), M_PWDDESC, M_WAITOK | M_ZERO); 2250 2251 PWDDESC_LOCK_INIT(newpdp); 2252 refcount_init(&newpdp->pd_refcount, 1); 2253 newpdp->pd_cmask = CMASK; 2254 2255 if (pdp == NULL) { 2256 newpwd = pwd_alloc(); 2257 smr_serialized_store(&newpdp->pd_pwd, newpwd, true); 2258 return (newpdp); 2259 } 2260 2261 PWDDESC_XLOCK(pdp); 2262 newpwd = pwd_hold_pwddesc(pdp); 2263 smr_serialized_store(&newpdp->pd_pwd, newpwd, true); 2264 if (!keeplock) 2265 PWDDESC_XUNLOCK(pdp); 2266 return (newpdp); 2267 } 2268 2269 /* 2270 * Hold either filedesc or pwddesc of the passed process. 2271 * 2272 * The process lock is used to synchronize against the target exiting and 2273 * freeing the data. 2274 * 2275 * Clearing can be ilustrated in 3 steps: 2276 * 1. set the pointer to NULL. Either routine can race against it, hence 2277 * atomic_load_ptr. 2278 * 2. observe the process lock as not taken. Until then fdhold/pdhold can 2279 * race to either still see the pointer or find NULL. It is still safe to 2280 * grab a reference as clearing is stalled. 2281 * 3. after the lock is observed as not taken, any fdhold/pdhold calls are 2282 * guaranteed to see NULL, making it safe to finish clearing 2283 */ 2284 static struct filedesc * 2285 fdhold(struct proc *p) 2286 { 2287 struct filedesc *fdp; 2288 2289 PROC_LOCK_ASSERT(p, MA_OWNED); 2290 fdp = atomic_load_ptr(&p->p_fd); 2291 if (fdp != NULL) 2292 refcount_acquire(&fdp->fd_holdcnt); 2293 return (fdp); 2294 } 2295 2296 static struct pwddesc * 2297 pdhold(struct proc *p) 2298 { 2299 struct pwddesc *pdp; 2300 2301 PROC_LOCK_ASSERT(p, MA_OWNED); 2302 pdp = atomic_load_ptr(&p->p_pd); 2303 if (pdp != NULL) 2304 refcount_acquire(&pdp->pd_refcount); 2305 return (pdp); 2306 } 2307 2308 static void 2309 fddrop(struct filedesc *fdp) 2310 { 2311 2312 if (refcount_load(&fdp->fd_holdcnt) > 1) { 2313 if (refcount_release(&fdp->fd_holdcnt) == 0) 2314 return; 2315 } 2316 2317 FILEDESC_LOCK_DESTROY(fdp); 2318 uma_zfree(filedesc0_zone, fdp); 2319 } 2320 2321 static void 2322 pddrop(struct pwddesc *pdp) 2323 { 2324 struct pwd *pwd; 2325 2326 if (refcount_release_if_not_last(&pdp->pd_refcount)) 2327 return; 2328 2329 PWDDESC_XLOCK(pdp); 2330 if (refcount_release(&pdp->pd_refcount) == 0) { 2331 PWDDESC_XUNLOCK(pdp); 2332 return; 2333 } 2334 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 2335 pwd_set(pdp, NULL); 2336 PWDDESC_XUNLOCK(pdp); 2337 pwd_drop(pwd); 2338 2339 PWDDESC_LOCK_DESTROY(pdp); 2340 free(pdp, M_PWDDESC); 2341 } 2342 2343 /* 2344 * Share a filedesc structure. 2345 */ 2346 struct filedesc * 2347 fdshare(struct filedesc *fdp) 2348 { 2349 2350 refcount_acquire(&fdp->fd_refcnt); 2351 return (fdp); 2352 } 2353 2354 /* 2355 * Share a pwddesc structure. 2356 */ 2357 struct pwddesc * 2358 pdshare(struct pwddesc *pdp) 2359 { 2360 refcount_acquire(&pdp->pd_refcount); 2361 return (pdp); 2362 } 2363 2364 /* 2365 * Unshare a filedesc structure, if necessary by making a copy 2366 */ 2367 void 2368 fdunshare(struct thread *td) 2369 { 2370 struct filedesc *tmp; 2371 struct proc *p = td->td_proc; 2372 2373 if (refcount_load(&p->p_fd->fd_refcnt) == 1) 2374 return; 2375 2376 tmp = fdcopy(p->p_fd); 2377 fdescfree(td); 2378 p->p_fd = tmp; 2379 } 2380 2381 /* 2382 * Unshare a pwddesc structure. 2383 */ 2384 void 2385 pdunshare(struct thread *td) 2386 { 2387 struct pwddesc *pdp; 2388 struct proc *p; 2389 2390 p = td->td_proc; 2391 /* Not shared. */ 2392 if (refcount_load(&p->p_pd->pd_refcount) == 1) 2393 return; 2394 2395 pdp = pdcopy(p->p_pd); 2396 pdescfree(td); 2397 p->p_pd = pdp; 2398 } 2399 2400 /* 2401 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 2402 * this is to ease callers, not catch errors. 2403 */ 2404 struct filedesc * 2405 fdcopy(struct filedesc *fdp) 2406 { 2407 struct filedesc *newfdp; 2408 struct filedescent *nfde, *ofde; 2409 int i, lastfile; 2410 2411 MPASS(fdp != NULL); 2412 2413 newfdp = fdinit(); 2414 FILEDESC_SLOCK(fdp); 2415 for (;;) { 2416 lastfile = fdlastfile(fdp); 2417 if (lastfile < newfdp->fd_nfiles) 2418 break; 2419 FILEDESC_SUNLOCK(fdp); 2420 fdgrowtable(newfdp, lastfile + 1); 2421 FILEDESC_SLOCK(fdp); 2422 } 2423 /* copy all passable descriptors (i.e. not kqueue) */ 2424 newfdp->fd_freefile = fdp->fd_freefile; 2425 FILEDESC_FOREACH_FDE(fdp, i, ofde) { 2426 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0 || 2427 !fhold(ofde->fde_file)) { 2428 if (newfdp->fd_freefile == fdp->fd_freefile) 2429 newfdp->fd_freefile = i; 2430 continue; 2431 } 2432 nfde = &newfdp->fd_ofiles[i]; 2433 *nfde = *ofde; 2434 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 2435 fdused_init(newfdp, i); 2436 } 2437 MPASS(newfdp->fd_freefile != -1); 2438 FILEDESC_SUNLOCK(fdp); 2439 return (newfdp); 2440 } 2441 2442 /* 2443 * Copy a pwddesc structure. 2444 */ 2445 struct pwddesc * 2446 pdcopy(struct pwddesc *pdp) 2447 { 2448 struct pwddesc *newpdp; 2449 2450 MPASS(pdp != NULL); 2451 2452 newpdp = pdinit(pdp, true); 2453 newpdp->pd_cmask = pdp->pd_cmask; 2454 PWDDESC_XUNLOCK(pdp); 2455 return (newpdp); 2456 } 2457 2458 /* 2459 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e. 2460 * one of processes using it exits) and the table used to be shared. 2461 */ 2462 static void 2463 fdclearlocks(struct thread *td) 2464 { 2465 struct filedesc *fdp; 2466 struct filedesc_to_leader *fdtol; 2467 struct flock lf; 2468 struct file *fp; 2469 struct proc *p; 2470 struct vnode *vp; 2471 int i; 2472 2473 p = td->td_proc; 2474 fdp = p->p_fd; 2475 fdtol = p->p_fdtol; 2476 MPASS(fdtol != NULL); 2477 2478 FILEDESC_XLOCK(fdp); 2479 KASSERT(fdtol->fdl_refcount > 0, 2480 ("filedesc_to_refcount botch: fdl_refcount=%d", 2481 fdtol->fdl_refcount)); 2482 if (fdtol->fdl_refcount == 1 && 2483 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2484 FILEDESC_FOREACH_FP(fdp, i, fp) { 2485 if (fp->f_type != DTYPE_VNODE || 2486 !fhold(fp)) 2487 continue; 2488 FILEDESC_XUNLOCK(fdp); 2489 lf.l_whence = SEEK_SET; 2490 lf.l_start = 0; 2491 lf.l_len = 0; 2492 lf.l_type = F_UNLCK; 2493 vp = fp->f_vnode; 2494 (void) VOP_ADVLOCK(vp, 2495 (caddr_t)p->p_leader, F_UNLCK, 2496 &lf, F_POSIX); 2497 FILEDESC_XLOCK(fdp); 2498 fdrop(fp, td); 2499 } 2500 } 2501 retry: 2502 if (fdtol->fdl_refcount == 1) { 2503 if (fdp->fd_holdleaderscount > 0 && 2504 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2505 /* 2506 * close() or kern_dup() has cleared a reference 2507 * in a shared file descriptor table. 2508 */ 2509 fdp->fd_holdleaderswakeup = 1; 2510 sx_sleep(&fdp->fd_holdleaderscount, 2511 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2512 goto retry; 2513 } 2514 if (fdtol->fdl_holdcount > 0) { 2515 /* 2516 * Ensure that fdtol->fdl_leader remains 2517 * valid in closef(). 2518 */ 2519 fdtol->fdl_wakeup = 1; 2520 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2521 "fdlhold", 0); 2522 goto retry; 2523 } 2524 } 2525 fdtol->fdl_refcount--; 2526 if (fdtol->fdl_refcount == 0 && 2527 fdtol->fdl_holdcount == 0) { 2528 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2529 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2530 } else 2531 fdtol = NULL; 2532 p->p_fdtol = NULL; 2533 FILEDESC_XUNLOCK(fdp); 2534 if (fdtol != NULL) 2535 free(fdtol, M_FILEDESC_TO_LEADER); 2536 } 2537 2538 /* 2539 * Release a filedesc structure. 2540 */ 2541 static void 2542 fdescfree_fds(struct thread *td, struct filedesc *fdp) 2543 { 2544 struct filedesc0 *fdp0; 2545 struct freetable *ft, *tft; 2546 struct filedescent *fde; 2547 struct file *fp; 2548 int i; 2549 2550 KASSERT(refcount_load(&fdp->fd_refcnt) == 0, 2551 ("%s: fd table %p carries references", __func__, fdp)); 2552 2553 /* 2554 * Serialize with threads iterating over the table, if any. 2555 */ 2556 if (refcount_load(&fdp->fd_holdcnt) > 1) { 2557 FILEDESC_XLOCK(fdp); 2558 FILEDESC_XUNLOCK(fdp); 2559 } 2560 2561 FILEDESC_FOREACH_FDE(fdp, i, fde) { 2562 fp = fde->fde_file; 2563 fdefree_last(fde); 2564 (void) closef(fp, td); 2565 } 2566 2567 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2568 free(fdp->fd_map, M_FILEDESC); 2569 if (fdp->fd_nfiles > NDFILE) 2570 free(fdp->fd_files, M_FILEDESC); 2571 2572 fdp0 = (struct filedesc0 *)fdp; 2573 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft) 2574 free(ft->ft_table, M_FILEDESC); 2575 2576 fddrop(fdp); 2577 } 2578 2579 void 2580 fdescfree(struct thread *td) 2581 { 2582 struct proc *p; 2583 struct filedesc *fdp; 2584 2585 p = td->td_proc; 2586 fdp = p->p_fd; 2587 MPASS(fdp != NULL); 2588 2589 #ifdef RACCT 2590 if (RACCT_ENABLED()) 2591 racct_set_unlocked(p, RACCT_NOFILE, 0); 2592 #endif 2593 2594 if (p->p_fdtol != NULL) 2595 fdclearlocks(td); 2596 2597 /* 2598 * Check fdhold for an explanation. 2599 */ 2600 atomic_store_ptr(&p->p_fd, NULL); 2601 atomic_thread_fence_seq_cst(); 2602 PROC_WAIT_UNLOCKED(p); 2603 2604 if (refcount_release(&fdp->fd_refcnt) == 0) 2605 return; 2606 2607 fdescfree_fds(td, fdp); 2608 } 2609 2610 void 2611 pdescfree(struct thread *td) 2612 { 2613 struct proc *p; 2614 struct pwddesc *pdp; 2615 2616 p = td->td_proc; 2617 pdp = p->p_pd; 2618 MPASS(pdp != NULL); 2619 2620 /* 2621 * Check pdhold for an explanation. 2622 */ 2623 atomic_store_ptr(&p->p_pd, NULL); 2624 atomic_thread_fence_seq_cst(); 2625 PROC_WAIT_UNLOCKED(p); 2626 2627 pddrop(pdp); 2628 } 2629 2630 /* 2631 * For setugid programs, we don't want to people to use that setugidness 2632 * to generate error messages which write to a file which otherwise would 2633 * otherwise be off-limits to the process. We check for filesystems where 2634 * the vnode can change out from under us after execve (like [lin]procfs). 2635 * 2636 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is 2637 * sufficient. We also don't check for setugidness since we know we are. 2638 */ 2639 static bool 2640 is_unsafe(struct file *fp) 2641 { 2642 struct vnode *vp; 2643 2644 if (fp->f_type != DTYPE_VNODE) 2645 return (false); 2646 2647 vp = fp->f_vnode; 2648 return ((vp->v_vflag & VV_PROCDEP) != 0); 2649 } 2650 2651 /* 2652 * Make this setguid thing safe, if at all possible. 2653 */ 2654 void 2655 fdsetugidsafety(struct thread *td) 2656 { 2657 struct filedesc *fdp; 2658 struct file *fp; 2659 int i; 2660 2661 fdp = td->td_proc->p_fd; 2662 KASSERT(refcount_load(&fdp->fd_refcnt) == 1, 2663 ("the fdtable should not be shared")); 2664 MPASS(fdp->fd_nfiles >= 3); 2665 for (i = 0; i <= 2; i++) { 2666 fp = fdp->fd_ofiles[i].fde_file; 2667 if (fp != NULL && is_unsafe(fp)) { 2668 FILEDESC_XLOCK(fdp); 2669 knote_fdclose(td, i); 2670 /* 2671 * NULL-out descriptor prior to close to avoid 2672 * a race while close blocks. 2673 */ 2674 fdfree(fdp, i); 2675 FILEDESC_XUNLOCK(fdp); 2676 (void) closef(fp, td); 2677 } 2678 } 2679 } 2680 2681 /* 2682 * If a specific file object occupies a specific file descriptor, close the 2683 * file descriptor entry and drop a reference on the file object. This is a 2684 * convenience function to handle a subsequent error in a function that calls 2685 * falloc() that handles the race that another thread might have closed the 2686 * file descriptor out from under the thread creating the file object. 2687 */ 2688 void 2689 fdclose(struct thread *td, struct file *fp, int idx) 2690 { 2691 struct filedesc *fdp = td->td_proc->p_fd; 2692 2693 FILEDESC_XLOCK(fdp); 2694 if (fdp->fd_ofiles[idx].fde_file == fp) { 2695 fdfree(fdp, idx); 2696 FILEDESC_XUNLOCK(fdp); 2697 fdrop(fp, td); 2698 } else 2699 FILEDESC_XUNLOCK(fdp); 2700 } 2701 2702 /* 2703 * Close any files on exec? 2704 */ 2705 void 2706 fdcloseexec(struct thread *td) 2707 { 2708 struct filedesc *fdp; 2709 struct filedescent *fde; 2710 struct file *fp; 2711 int i; 2712 2713 fdp = td->td_proc->p_fd; 2714 KASSERT(refcount_load(&fdp->fd_refcnt) == 1, 2715 ("the fdtable should not be shared")); 2716 FILEDESC_FOREACH_FDE(fdp, i, fde) { 2717 fp = fde->fde_file; 2718 if (fp->f_type == DTYPE_MQUEUE || 2719 (fde->fde_flags & UF_EXCLOSE)) { 2720 FILEDESC_XLOCK(fdp); 2721 fdfree(fdp, i); 2722 (void) closefp(fdp, i, fp, td, false, false); 2723 FILEDESC_UNLOCK_ASSERT(fdp); 2724 } 2725 } 2726 } 2727 2728 /* 2729 * It is unsafe for set[ug]id processes to be started with file 2730 * descriptors 0..2 closed, as these descriptors are given implicit 2731 * significance in the Standard C library. fdcheckstd() will create a 2732 * descriptor referencing /dev/null for each of stdin, stdout, and 2733 * stderr that is not already open. 2734 */ 2735 int 2736 fdcheckstd(struct thread *td) 2737 { 2738 struct filedesc *fdp; 2739 register_t save; 2740 int i, error, devnull; 2741 2742 fdp = td->td_proc->p_fd; 2743 KASSERT(refcount_load(&fdp->fd_refcnt) == 1, 2744 ("the fdtable should not be shared")); 2745 MPASS(fdp->fd_nfiles >= 3); 2746 devnull = -1; 2747 for (i = 0; i <= 2; i++) { 2748 if (fdp->fd_ofiles[i].fde_file != NULL) 2749 continue; 2750 2751 save = td->td_retval[0]; 2752 if (devnull != -1) { 2753 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i); 2754 } else { 2755 error = kern_openat(td, AT_FDCWD, "/dev/null", 2756 UIO_SYSSPACE, O_RDWR, 0); 2757 if (error == 0) { 2758 devnull = td->td_retval[0]; 2759 KASSERT(devnull == i, ("we didn't get our fd")); 2760 } 2761 } 2762 td->td_retval[0] = save; 2763 if (error != 0) 2764 return (error); 2765 } 2766 return (0); 2767 } 2768 2769 /* 2770 * Internal form of close. Decrement reference count on file structure. 2771 * Note: td may be NULL when closing a file that was being passed in a 2772 * message. 2773 */ 2774 int 2775 closef(struct file *fp, struct thread *td) 2776 { 2777 struct vnode *vp; 2778 struct flock lf; 2779 struct filedesc_to_leader *fdtol; 2780 struct filedesc *fdp; 2781 2782 MPASS(td != NULL); 2783 2784 /* 2785 * POSIX record locking dictates that any close releases ALL 2786 * locks owned by this process. This is handled by setting 2787 * a flag in the unlock to free ONLY locks obeying POSIX 2788 * semantics, and not to free BSD-style file locks. 2789 * If the descriptor was in a message, POSIX-style locks 2790 * aren't passed with the descriptor, and the thread pointer 2791 * will be NULL. Callers should be careful only to pass a 2792 * NULL thread pointer when there really is no owning 2793 * context that might have locks, or the locks will be 2794 * leaked. 2795 */ 2796 if (fp->f_type == DTYPE_VNODE) { 2797 vp = fp->f_vnode; 2798 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2799 lf.l_whence = SEEK_SET; 2800 lf.l_start = 0; 2801 lf.l_len = 0; 2802 lf.l_type = F_UNLCK; 2803 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2804 F_UNLCK, &lf, F_POSIX); 2805 } 2806 fdtol = td->td_proc->p_fdtol; 2807 if (fdtol != NULL) { 2808 /* 2809 * Handle special case where file descriptor table is 2810 * shared between multiple process leaders. 2811 */ 2812 fdp = td->td_proc->p_fd; 2813 FILEDESC_XLOCK(fdp); 2814 for (fdtol = fdtol->fdl_next; 2815 fdtol != td->td_proc->p_fdtol; 2816 fdtol = fdtol->fdl_next) { 2817 if ((fdtol->fdl_leader->p_flag & 2818 P_ADVLOCK) == 0) 2819 continue; 2820 fdtol->fdl_holdcount++; 2821 FILEDESC_XUNLOCK(fdp); 2822 lf.l_whence = SEEK_SET; 2823 lf.l_start = 0; 2824 lf.l_len = 0; 2825 lf.l_type = F_UNLCK; 2826 vp = fp->f_vnode; 2827 (void) VOP_ADVLOCK(vp, 2828 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2829 F_POSIX); 2830 FILEDESC_XLOCK(fdp); 2831 fdtol->fdl_holdcount--; 2832 if (fdtol->fdl_holdcount == 0 && 2833 fdtol->fdl_wakeup != 0) { 2834 fdtol->fdl_wakeup = 0; 2835 wakeup(fdtol); 2836 } 2837 } 2838 FILEDESC_XUNLOCK(fdp); 2839 } 2840 } 2841 return (fdrop_close(fp, td)); 2842 } 2843 2844 /* 2845 * Hack for file descriptor passing code. 2846 */ 2847 void 2848 closef_nothread(struct file *fp) 2849 { 2850 2851 fdrop(fp, NULL); 2852 } 2853 2854 /* 2855 * Initialize the file pointer with the specified properties. 2856 * 2857 * The ops are set with release semantics to be certain that the flags, type, 2858 * and data are visible when ops is. This is to prevent ops methods from being 2859 * called with bad data. 2860 */ 2861 void 2862 finit(struct file *fp, u_int flag, short type, void *data, 2863 const struct fileops *ops) 2864 { 2865 fp->f_data = data; 2866 fp->f_flag = flag; 2867 fp->f_type = type; 2868 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2869 } 2870 2871 void 2872 finit_vnode(struct file *fp, u_int flag, void *data, const struct fileops *ops) 2873 { 2874 fp->f_seqcount[UIO_READ] = 1; 2875 fp->f_seqcount[UIO_WRITE] = 1; 2876 finit(fp, (flag & FMASK) | (fp->f_flag & FHASLOCK), DTYPE_VNODE, 2877 data, ops); 2878 } 2879 2880 int 2881 fget_cap_noref(struct filedesc *fdp, int fd, const cap_rights_t *needrightsp, 2882 struct file **fpp, struct filecaps *havecapsp) 2883 { 2884 struct filedescent *fde; 2885 int error; 2886 2887 FILEDESC_LOCK_ASSERT(fdp); 2888 2889 *fpp = NULL; 2890 fde = fdeget_noref(fdp, fd); 2891 if (fde == NULL) { 2892 error = EBADF; 2893 goto out; 2894 } 2895 2896 #ifdef CAPABILITIES 2897 error = cap_check(cap_rights_fde_inline(fde), needrightsp); 2898 if (error != 0) 2899 goto out; 2900 #endif 2901 2902 if (havecapsp != NULL) 2903 filecaps_copy(&fde->fde_caps, havecapsp, true); 2904 2905 *fpp = fde->fde_file; 2906 2907 error = 0; 2908 out: 2909 return (error); 2910 } 2911 2912 #ifdef CAPABILITIES 2913 int 2914 fget_cap(struct thread *td, int fd, const cap_rights_t *needrightsp, 2915 struct file **fpp, struct filecaps *havecapsp) 2916 { 2917 struct filedesc *fdp = td->td_proc->p_fd; 2918 int error; 2919 struct file *fp; 2920 seqc_t seq; 2921 2922 *fpp = NULL; 2923 for (;;) { 2924 error = fget_unlocked_seq(td, fd, needrightsp, &fp, &seq); 2925 if (error != 0) 2926 return (error); 2927 2928 if (havecapsp != NULL) { 2929 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, 2930 havecapsp, false)) { 2931 fdrop(fp, td); 2932 goto get_locked; 2933 } 2934 } 2935 2936 if (!fd_modified(fdp, fd, seq)) 2937 break; 2938 fdrop(fp, td); 2939 } 2940 2941 *fpp = fp; 2942 return (0); 2943 2944 get_locked: 2945 FILEDESC_SLOCK(fdp); 2946 error = fget_cap_noref(fdp, fd, needrightsp, fpp, havecapsp); 2947 if (error == 0 && !fhold(*fpp)) 2948 error = EBADF; 2949 FILEDESC_SUNLOCK(fdp); 2950 return (error); 2951 } 2952 #else 2953 int 2954 fget_cap(struct thread *td, int fd, const cap_rights_t *needrightsp, 2955 struct file **fpp, struct filecaps *havecapsp) 2956 { 2957 int error; 2958 error = fget_unlocked(td, fd, needrightsp, fpp); 2959 if (havecapsp != NULL && error == 0) 2960 filecaps_fill(havecapsp); 2961 2962 return (error); 2963 } 2964 #endif 2965 2966 int 2967 fget_remote(struct thread *td, struct proc *p, int fd, struct file **fpp) 2968 { 2969 struct filedesc *fdp; 2970 struct file *fp; 2971 int error; 2972 2973 if (p == td->td_proc) /* curproc */ 2974 return (fget_unlocked(td, fd, &cap_no_rights, fpp)); 2975 2976 PROC_LOCK(p); 2977 fdp = fdhold(p); 2978 PROC_UNLOCK(p); 2979 if (fdp == NULL) 2980 return (ENOENT); 2981 FILEDESC_SLOCK(fdp); 2982 if (refcount_load(&fdp->fd_refcnt) != 0) { 2983 fp = fget_noref(fdp, fd); 2984 if (fp != NULL && fhold(fp)) { 2985 *fpp = fp; 2986 error = 0; 2987 } else { 2988 error = EBADF; 2989 } 2990 } else { 2991 error = ENOENT; 2992 } 2993 FILEDESC_SUNLOCK(fdp); 2994 fddrop(fdp); 2995 return (error); 2996 } 2997 2998 int 2999 fget_remote_foreach(struct thread *td, struct proc *p, 3000 int (*fn)(struct proc *, int, struct file *, void *), void *arg) 3001 { 3002 struct filedesc *fdp; 3003 struct fdescenttbl *fdt; 3004 struct file *fp; 3005 int error, error1, fd, highfd; 3006 3007 error = 0; 3008 PROC_LOCK(p); 3009 fdp = fdhold(p); 3010 PROC_UNLOCK(p); 3011 if (fdp == NULL) 3012 return (ENOENT); 3013 3014 FILEDESC_SLOCK(fdp); 3015 if (refcount_load(&fdp->fd_refcnt) != 0) { 3016 fdt = atomic_load_ptr(&fdp->fd_files); 3017 highfd = fdt->fdt_nfiles - 1; 3018 FILEDESC_SUNLOCK(fdp); 3019 } else { 3020 error = ENOENT; 3021 FILEDESC_SUNLOCK(fdp); 3022 goto out; 3023 } 3024 3025 for (fd = 0; fd <= highfd; fd++) { 3026 error1 = fget_remote(td, p, fd, &fp); 3027 if (error1 != 0) 3028 continue; 3029 error = fn(p, fd, fp, arg); 3030 fdrop(fp, td); 3031 if (error != 0) 3032 break; 3033 } 3034 out: 3035 fddrop(fdp); 3036 return (error); 3037 } 3038 3039 #ifdef CAPABILITIES 3040 int 3041 fgetvp_lookup_smr(struct nameidata *ndp, struct vnode **vpp, bool *fsearch) 3042 { 3043 const struct filedescent *fde; 3044 const struct fdescenttbl *fdt; 3045 struct filedesc *fdp; 3046 struct file *fp; 3047 struct vnode *vp; 3048 const cap_rights_t *haverights; 3049 cap_rights_t rights; 3050 seqc_t seq; 3051 int fd; 3052 3053 VFS_SMR_ASSERT_ENTERED(); 3054 3055 fd = ndp->ni_dirfd; 3056 rights = *ndp->ni_rightsneeded; 3057 cap_rights_set_one(&rights, CAP_LOOKUP); 3058 3059 fdp = curproc->p_fd; 3060 fdt = fdp->fd_files; 3061 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3062 return (EBADF); 3063 seq = seqc_read_notmodify(fd_seqc(fdt, fd)); 3064 fde = &fdt->fdt_ofiles[fd]; 3065 haverights = cap_rights_fde_inline(fde); 3066 fp = fde->fde_file; 3067 if (__predict_false(fp == NULL)) 3068 return (EAGAIN); 3069 if (__predict_false(cap_check_inline_transient(haverights, &rights))) 3070 return (EAGAIN); 3071 *fsearch = ((fp->f_flag & FSEARCH) != 0); 3072 vp = fp->f_vnode; 3073 if (__predict_false(vp == NULL)) { 3074 return (EAGAIN); 3075 } 3076 if (!filecaps_copy(&fde->fde_caps, &ndp->ni_filecaps, false)) { 3077 return (EAGAIN); 3078 } 3079 /* 3080 * Use an acquire barrier to force re-reading of fdt so it is 3081 * refreshed for verification. 3082 */ 3083 atomic_thread_fence_acq(); 3084 fdt = fdp->fd_files; 3085 if (__predict_false(!seqc_consistent_no_fence(fd_seqc(fdt, fd), seq))) 3086 return (EAGAIN); 3087 /* 3088 * If file descriptor doesn't have all rights, 3089 * all lookups relative to it must also be 3090 * strictly relative. 3091 * 3092 * Not yet supported by fast path. 3093 */ 3094 CAP_ALL(&rights); 3095 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights, &rights) || 3096 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL || 3097 ndp->ni_filecaps.fc_nioctls != -1) { 3098 #ifdef notyet 3099 ndp->ni_lcf |= NI_LCF_STRICTREL; 3100 #else 3101 return (EAGAIN); 3102 #endif 3103 } 3104 *vpp = vp; 3105 return (0); 3106 } 3107 #else 3108 int 3109 fgetvp_lookup_smr(struct nameidata *ndp, struct vnode **vpp, bool *fsearch) 3110 { 3111 const struct fdescenttbl *fdt; 3112 struct filedesc *fdp; 3113 struct file *fp; 3114 struct vnode *vp; 3115 int fd; 3116 3117 VFS_SMR_ASSERT_ENTERED(); 3118 3119 fd = ndp->ni_dirfd; 3120 fdp = curproc->p_fd; 3121 fdt = fdp->fd_files; 3122 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3123 return (EBADF); 3124 fp = fdt->fdt_ofiles[fd].fde_file; 3125 if (__predict_false(fp == NULL)) 3126 return (EAGAIN); 3127 *fsearch = ((fp->f_flag & FSEARCH) != 0); 3128 vp = fp->f_vnode; 3129 if (__predict_false(vp == NULL || vp->v_type != VDIR)) { 3130 return (EAGAIN); 3131 } 3132 /* 3133 * Use an acquire barrier to force re-reading of fdt so it is 3134 * refreshed for verification. 3135 */ 3136 atomic_thread_fence_acq(); 3137 fdt = fdp->fd_files; 3138 if (__predict_false(fp != fdt->fdt_ofiles[fd].fde_file)) 3139 return (EAGAIN); 3140 filecaps_fill(&ndp->ni_filecaps); 3141 *vpp = vp; 3142 return (0); 3143 } 3144 #endif 3145 3146 int 3147 fgetvp_lookup(struct nameidata *ndp, struct vnode **vpp) 3148 { 3149 struct thread *td; 3150 struct file *fp; 3151 struct vnode *vp; 3152 struct componentname *cnp; 3153 cap_rights_t rights; 3154 int error; 3155 3156 td = curthread; 3157 rights = *ndp->ni_rightsneeded; 3158 cap_rights_set_one(&rights, CAP_LOOKUP); 3159 cnp = &ndp->ni_cnd; 3160 3161 error = fget_cap(td, ndp->ni_dirfd, &rights, &fp, &ndp->ni_filecaps); 3162 if (__predict_false(error != 0)) 3163 return (error); 3164 if (__predict_false(fp->f_ops == &badfileops)) { 3165 error = EBADF; 3166 goto out_free; 3167 } 3168 vp = fp->f_vnode; 3169 if (__predict_false(vp == NULL)) { 3170 error = ENOTDIR; 3171 goto out_free; 3172 } 3173 vrefact(vp); 3174 /* 3175 * XXX does not check for VDIR, handled by namei_setup 3176 */ 3177 if ((fp->f_flag & FSEARCH) != 0) 3178 cnp->cn_flags |= NOEXECCHECK; 3179 fdrop(fp, td); 3180 3181 #ifdef CAPABILITIES 3182 /* 3183 * If file descriptor doesn't have all rights, 3184 * all lookups relative to it must also be 3185 * strictly relative. 3186 */ 3187 CAP_ALL(&rights); 3188 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights, &rights) || 3189 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL || 3190 ndp->ni_filecaps.fc_nioctls != -1) { 3191 ndp->ni_lcf |= NI_LCF_STRICTREL; 3192 ndp->ni_resflags |= NIRES_STRICTREL; 3193 } 3194 #endif 3195 3196 /* 3197 * TODO: avoid copying ioctl caps if it can be helped to begin with 3198 */ 3199 if ((cnp->cn_flags & WANTIOCTLCAPS) == 0) 3200 filecaps_free_ioctl(&ndp->ni_filecaps); 3201 3202 *vpp = vp; 3203 return (0); 3204 3205 out_free: 3206 filecaps_free(&ndp->ni_filecaps); 3207 fdrop(fp, td); 3208 return (error); 3209 } 3210 3211 /* 3212 * Fetch the descriptor locklessly. 3213 * 3214 * We avoid fdrop() races by never raising a refcount above 0. To accomplish 3215 * this we have to use a cmpset loop rather than an atomic_add. The descriptor 3216 * must be re-verified once we acquire a reference to be certain that the 3217 * identity is still correct and we did not lose a race due to preemption. 3218 * 3219 * Force a reload of fdt when looping. Another thread could reallocate 3220 * the table before this fd was closed, so it is possible that there is 3221 * a stale fp pointer in cached version. 3222 */ 3223 #ifdef CAPABILITIES 3224 static int 3225 fget_unlocked_seq(struct thread *td, int fd, const cap_rights_t *needrightsp, 3226 struct file **fpp, seqc_t *seqp) 3227 { 3228 struct filedesc *fdp; 3229 const struct filedescent *fde; 3230 const struct fdescenttbl *fdt; 3231 struct file *fp; 3232 seqc_t seq; 3233 cap_rights_t haverights; 3234 int error; 3235 3236 fdp = td->td_proc->p_fd; 3237 fdt = fdp->fd_files; 3238 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3239 return (EBADF); 3240 3241 for (;;) { 3242 seq = seqc_read_notmodify(fd_seqc(fdt, fd)); 3243 fde = &fdt->fdt_ofiles[fd]; 3244 haverights = *cap_rights_fde_inline(fde); 3245 fp = fde->fde_file; 3246 if (__predict_false(fp == NULL)) { 3247 if (seqc_consistent(fd_seqc(fdt, fd), seq)) 3248 return (EBADF); 3249 fdt = atomic_load_ptr(&fdp->fd_files); 3250 continue; 3251 } 3252 error = cap_check_inline(&haverights, needrightsp); 3253 if (__predict_false(error != 0)) { 3254 if (seqc_consistent(fd_seqc(fdt, fd), seq)) 3255 return (error); 3256 fdt = atomic_load_ptr(&fdp->fd_files); 3257 continue; 3258 } 3259 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count))) { 3260 fdt = atomic_load_ptr(&fdp->fd_files); 3261 continue; 3262 } 3263 /* 3264 * Use an acquire barrier to force re-reading of fdt so it is 3265 * refreshed for verification. 3266 */ 3267 atomic_thread_fence_acq(); 3268 fdt = fdp->fd_files; 3269 if (seqc_consistent_no_fence(fd_seqc(fdt, fd), seq)) 3270 break; 3271 fdrop(fp, td); 3272 } 3273 *fpp = fp; 3274 if (seqp != NULL) { 3275 *seqp = seq; 3276 } 3277 return (0); 3278 } 3279 #else 3280 static int 3281 fget_unlocked_seq(struct thread *td, int fd, const cap_rights_t *needrightsp, 3282 struct file **fpp, seqc_t *seqp __unused) 3283 { 3284 struct filedesc *fdp; 3285 const struct fdescenttbl *fdt; 3286 struct file *fp; 3287 3288 fdp = td->td_proc->p_fd; 3289 fdt = fdp->fd_files; 3290 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3291 return (EBADF); 3292 3293 for (;;) { 3294 fp = fdt->fdt_ofiles[fd].fde_file; 3295 if (__predict_false(fp == NULL)) 3296 return (EBADF); 3297 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count))) { 3298 fdt = atomic_load_ptr(&fdp->fd_files); 3299 continue; 3300 } 3301 /* 3302 * Use an acquire barrier to force re-reading of fdt so it is 3303 * refreshed for verification. 3304 */ 3305 atomic_thread_fence_acq(); 3306 fdt = fdp->fd_files; 3307 if (__predict_true(fp == fdt->fdt_ofiles[fd].fde_file)) 3308 break; 3309 fdrop(fp, td); 3310 } 3311 *fpp = fp; 3312 return (0); 3313 } 3314 #endif 3315 3316 /* 3317 * See the comments in fget_unlocked_seq for an explanation of how this works. 3318 * 3319 * This is a simplified variant which bails out to the aforementioned routine 3320 * if anything goes wrong. In practice this only happens when userspace is 3321 * racing with itself. 3322 */ 3323 int 3324 fget_unlocked(struct thread *td, int fd, const cap_rights_t *needrightsp, 3325 struct file **fpp) 3326 { 3327 struct filedesc *fdp; 3328 #ifdef CAPABILITIES 3329 const struct filedescent *fde; 3330 #endif 3331 const struct fdescenttbl *fdt; 3332 struct file *fp; 3333 #ifdef CAPABILITIES 3334 seqc_t seq; 3335 const cap_rights_t *haverights; 3336 #endif 3337 3338 fdp = td->td_proc->p_fd; 3339 fdt = fdp->fd_files; 3340 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) { 3341 *fpp = NULL; 3342 return (EBADF); 3343 } 3344 #ifdef CAPABILITIES 3345 seq = seqc_read_notmodify(fd_seqc(fdt, fd)); 3346 fde = &fdt->fdt_ofiles[fd]; 3347 haverights = cap_rights_fde_inline(fde); 3348 fp = fde->fde_file; 3349 #else 3350 fp = fdt->fdt_ofiles[fd].fde_file; 3351 #endif 3352 if (__predict_false(fp == NULL)) 3353 goto out_fallback; 3354 #ifdef CAPABILITIES 3355 if (__predict_false(cap_check_inline_transient(haverights, needrightsp))) 3356 goto out_fallback; 3357 #endif 3358 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count))) 3359 goto out_fallback; 3360 3361 /* 3362 * Use an acquire barrier to force re-reading of fdt so it is 3363 * refreshed for verification. 3364 */ 3365 atomic_thread_fence_acq(); 3366 fdt = fdp->fd_files; 3367 #ifdef CAPABILITIES 3368 if (__predict_false(!seqc_consistent_no_fence(fd_seqc(fdt, fd), seq))) 3369 #else 3370 if (__predict_false(fp != fdt->fdt_ofiles[fd].fde_file)) 3371 #endif 3372 goto out_fdrop; 3373 *fpp = fp; 3374 return (0); 3375 out_fdrop: 3376 fdrop(fp, td); 3377 out_fallback: 3378 *fpp = NULL; 3379 return (fget_unlocked_seq(td, fd, needrightsp, fpp, NULL)); 3380 } 3381 3382 /* 3383 * Translate fd -> file when the caller guarantees the file descriptor table 3384 * can't be changed by others. 3385 * 3386 * Note this does not mean the file object itself is only visible to the caller, 3387 * merely that it wont disappear without having to be referenced. 3388 * 3389 * Must be paired with fput_only_user. 3390 */ 3391 #ifdef CAPABILITIES 3392 int 3393 fget_only_user(struct filedesc *fdp, int fd, const cap_rights_t *needrightsp, 3394 struct file **fpp) 3395 { 3396 const struct filedescent *fde; 3397 const struct fdescenttbl *fdt; 3398 const cap_rights_t *haverights; 3399 struct file *fp; 3400 int error; 3401 3402 MPASS(FILEDESC_IS_ONLY_USER(fdp)); 3403 3404 *fpp = NULL; 3405 if (__predict_false(fd >= fdp->fd_nfiles)) 3406 return (EBADF); 3407 3408 fdt = fdp->fd_files; 3409 fde = &fdt->fdt_ofiles[fd]; 3410 fp = fde->fde_file; 3411 if (__predict_false(fp == NULL)) 3412 return (EBADF); 3413 MPASS(refcount_load(&fp->f_count) > 0); 3414 haverights = cap_rights_fde_inline(fde); 3415 error = cap_check_inline(haverights, needrightsp); 3416 if (__predict_false(error != 0)) 3417 return (error); 3418 *fpp = fp; 3419 return (0); 3420 } 3421 #else 3422 int 3423 fget_only_user(struct filedesc *fdp, int fd, const cap_rights_t *needrightsp, 3424 struct file **fpp) 3425 { 3426 struct file *fp; 3427 3428 MPASS(FILEDESC_IS_ONLY_USER(fdp)); 3429 3430 *fpp = NULL; 3431 if (__predict_false(fd >= fdp->fd_nfiles)) 3432 return (EBADF); 3433 3434 fp = fdp->fd_ofiles[fd].fde_file; 3435 if (__predict_false(fp == NULL)) 3436 return (EBADF); 3437 3438 MPASS(refcount_load(&fp->f_count) > 0); 3439 *fpp = fp; 3440 return (0); 3441 } 3442 #endif 3443 3444 /* 3445 * Extract the file pointer associated with the specified descriptor for the 3446 * current user process. 3447 * 3448 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 3449 * returned. 3450 * 3451 * File's rights will be checked against the capability rights mask. 3452 * 3453 * If an error occurred the non-zero error is returned and *fpp is set to 3454 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 3455 * responsible for fdrop(). 3456 */ 3457 static __inline int 3458 _fget(struct thread *td, int fd, struct file **fpp, int flags, 3459 const cap_rights_t *needrightsp) 3460 { 3461 struct file *fp; 3462 int error; 3463 3464 *fpp = NULL; 3465 error = fget_unlocked(td, fd, needrightsp, &fp); 3466 if (__predict_false(error != 0)) 3467 return (error); 3468 if (__predict_false(fp->f_ops == &badfileops)) { 3469 fdrop(fp, td); 3470 return (EBADF); 3471 } 3472 3473 /* 3474 * FREAD and FWRITE failure return EBADF as per POSIX. 3475 */ 3476 error = 0; 3477 switch (flags) { 3478 case FREAD: 3479 case FWRITE: 3480 if ((fp->f_flag & flags) == 0) 3481 error = EBADF; 3482 break; 3483 case FEXEC: 3484 if (fp->f_ops != &path_fileops && 3485 ((fp->f_flag & (FREAD | FEXEC)) == 0 || 3486 (fp->f_flag & FWRITE) != 0)) 3487 error = EBADF; 3488 break; 3489 case 0: 3490 break; 3491 default: 3492 KASSERT(0, ("wrong flags")); 3493 } 3494 3495 if (error != 0) { 3496 fdrop(fp, td); 3497 return (error); 3498 } 3499 3500 *fpp = fp; 3501 return (0); 3502 } 3503 3504 int 3505 fget(struct thread *td, int fd, const cap_rights_t *rightsp, struct file **fpp) 3506 { 3507 3508 return (_fget(td, fd, fpp, 0, rightsp)); 3509 } 3510 3511 int 3512 fget_mmap(struct thread *td, int fd, const cap_rights_t *rightsp, 3513 vm_prot_t *maxprotp, struct file **fpp) 3514 { 3515 int error; 3516 #ifndef CAPABILITIES 3517 error = _fget(td, fd, fpp, 0, rightsp); 3518 if (maxprotp != NULL) 3519 *maxprotp = VM_PROT_ALL; 3520 return (error); 3521 #else 3522 cap_rights_t fdrights; 3523 struct filedesc *fdp; 3524 struct file *fp; 3525 seqc_t seq; 3526 3527 *fpp = NULL; 3528 fdp = td->td_proc->p_fd; 3529 MPASS(cap_rights_is_set(rightsp, CAP_MMAP)); 3530 for (;;) { 3531 error = fget_unlocked_seq(td, fd, rightsp, &fp, &seq); 3532 if (__predict_false(error != 0)) 3533 return (error); 3534 if (__predict_false(fp->f_ops == &badfileops)) { 3535 fdrop(fp, td); 3536 return (EBADF); 3537 } 3538 if (maxprotp != NULL) 3539 fdrights = *cap_rights(fdp, fd); 3540 if (!fd_modified(fdp, fd, seq)) 3541 break; 3542 fdrop(fp, td); 3543 } 3544 3545 /* 3546 * If requested, convert capability rights to access flags. 3547 */ 3548 if (maxprotp != NULL) 3549 *maxprotp = cap_rights_to_vmprot(&fdrights); 3550 *fpp = fp; 3551 return (0); 3552 #endif 3553 } 3554 3555 int 3556 fget_read(struct thread *td, int fd, const cap_rights_t *rightsp, 3557 struct file **fpp) 3558 { 3559 3560 return (_fget(td, fd, fpp, FREAD, rightsp)); 3561 } 3562 3563 int 3564 fget_write(struct thread *td, int fd, const cap_rights_t *rightsp, 3565 struct file **fpp) 3566 { 3567 3568 return (_fget(td, fd, fpp, FWRITE, rightsp)); 3569 } 3570 3571 int 3572 fget_fcntl(struct thread *td, int fd, const cap_rights_t *rightsp, 3573 int needfcntl, struct file **fpp) 3574 { 3575 #ifndef CAPABILITIES 3576 return (fget_unlocked(td, fd, rightsp, fpp)); 3577 #else 3578 struct filedesc *fdp = td->td_proc->p_fd; 3579 struct file *fp; 3580 int error; 3581 seqc_t seq; 3582 3583 *fpp = NULL; 3584 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL)); 3585 for (;;) { 3586 error = fget_unlocked_seq(td, fd, rightsp, &fp, &seq); 3587 if (error != 0) 3588 return (error); 3589 error = cap_fcntl_check(fdp, fd, needfcntl); 3590 if (!fd_modified(fdp, fd, seq)) 3591 break; 3592 fdrop(fp, td); 3593 } 3594 if (error != 0) { 3595 fdrop(fp, td); 3596 return (error); 3597 } 3598 *fpp = fp; 3599 return (0); 3600 #endif 3601 } 3602 3603 /* 3604 * Like fget() but loads the underlying vnode, or returns an error if the 3605 * descriptor does not represent a vnode. Note that pipes use vnodes but 3606 * never have VM objects. The returned vnode will be vref()'d. 3607 * 3608 * XXX: what about the unused flags ? 3609 */ 3610 static __inline int 3611 _fgetvp(struct thread *td, int fd, int flags, const cap_rights_t *needrightsp, 3612 struct vnode **vpp) 3613 { 3614 struct file *fp; 3615 int error; 3616 3617 *vpp = NULL; 3618 error = _fget(td, fd, &fp, flags, needrightsp); 3619 if (error != 0) 3620 return (error); 3621 if (fp->f_vnode == NULL) { 3622 error = EINVAL; 3623 } else { 3624 *vpp = fp->f_vnode; 3625 vrefact(*vpp); 3626 } 3627 fdrop(fp, td); 3628 3629 return (error); 3630 } 3631 3632 int 3633 fgetvp(struct thread *td, int fd, const cap_rights_t *rightsp, 3634 struct vnode **vpp) 3635 { 3636 3637 return (_fgetvp(td, fd, 0, rightsp, vpp)); 3638 } 3639 3640 int 3641 fgetvp_rights(struct thread *td, int fd, const cap_rights_t *needrightsp, 3642 struct filecaps *havecaps, struct vnode **vpp) 3643 { 3644 struct filecaps caps; 3645 struct file *fp; 3646 int error; 3647 3648 error = fget_cap(td, fd, needrightsp, &fp, &caps); 3649 if (error != 0) 3650 return (error); 3651 if (fp->f_ops == &badfileops) { 3652 error = EBADF; 3653 goto out; 3654 } 3655 if (fp->f_vnode == NULL) { 3656 error = EINVAL; 3657 goto out; 3658 } 3659 3660 *havecaps = caps; 3661 *vpp = fp->f_vnode; 3662 vrefact(*vpp); 3663 fdrop(fp, td); 3664 3665 return (0); 3666 out: 3667 filecaps_free(&caps); 3668 fdrop(fp, td); 3669 return (error); 3670 } 3671 3672 int 3673 fgetvp_read(struct thread *td, int fd, const cap_rights_t *rightsp, 3674 struct vnode **vpp) 3675 { 3676 3677 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 3678 } 3679 3680 int 3681 fgetvp_exec(struct thread *td, int fd, const cap_rights_t *rightsp, 3682 struct vnode **vpp) 3683 { 3684 3685 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 3686 } 3687 3688 #ifdef notyet 3689 int 3690 fgetvp_write(struct thread *td, int fd, const cap_rights_t *rightsp, 3691 struct vnode **vpp) 3692 { 3693 3694 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 3695 } 3696 #endif 3697 3698 /* 3699 * Handle the last reference to a file being closed. 3700 * 3701 * Without the noinline attribute clang keeps inlining the func thorough this 3702 * file when fdrop is used. 3703 */ 3704 int __noinline 3705 _fdrop(struct file *fp, struct thread *td) 3706 { 3707 int error; 3708 3709 KASSERT(refcount_load(&fp->f_count) == 0, 3710 ("fdrop: fp %p count %d", fp, refcount_load(&fp->f_count))); 3711 3712 error = fo_close(fp, td); 3713 atomic_subtract_int(&openfiles, 1); 3714 crfree(fp->f_cred); 3715 free(fp->f_advice, M_FADVISE); 3716 uma_zfree(file_zone, fp); 3717 3718 return (error); 3719 } 3720 3721 /* 3722 * Apply an advisory lock on a file descriptor. 3723 * 3724 * Just attempt to get a record lock of the requested type on the entire file 3725 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 3726 */ 3727 #ifndef _SYS_SYSPROTO_H_ 3728 struct flock_args { 3729 int fd; 3730 int how; 3731 }; 3732 #endif 3733 /* ARGSUSED */ 3734 int 3735 sys_flock(struct thread *td, struct flock_args *uap) 3736 { 3737 struct file *fp; 3738 struct vnode *vp; 3739 struct flock lf; 3740 int error; 3741 3742 error = fget(td, uap->fd, &cap_flock_rights, &fp); 3743 if (error != 0) 3744 return (error); 3745 error = EOPNOTSUPP; 3746 if (fp->f_type != DTYPE_VNODE && fp->f_type != DTYPE_FIFO) { 3747 goto done; 3748 } 3749 if (fp->f_ops == &path_fileops) { 3750 goto done; 3751 } 3752 3753 error = 0; 3754 vp = fp->f_vnode; 3755 lf.l_whence = SEEK_SET; 3756 lf.l_start = 0; 3757 lf.l_len = 0; 3758 if (uap->how & LOCK_UN) { 3759 lf.l_type = F_UNLCK; 3760 atomic_clear_int(&fp->f_flag, FHASLOCK); 3761 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 3762 goto done; 3763 } 3764 if (uap->how & LOCK_EX) 3765 lf.l_type = F_WRLCK; 3766 else if (uap->how & LOCK_SH) 3767 lf.l_type = F_RDLCK; 3768 else { 3769 error = EBADF; 3770 goto done; 3771 } 3772 atomic_set_int(&fp->f_flag, FHASLOCK); 3773 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 3774 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 3775 done: 3776 fdrop(fp, td); 3777 return (error); 3778 } 3779 /* 3780 * Duplicate the specified descriptor to a free descriptor. 3781 */ 3782 int 3783 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 3784 int openerror, int *indxp) 3785 { 3786 struct filedescent *newfde, *oldfde; 3787 struct file *fp; 3788 u_long *ioctls; 3789 int error, indx; 3790 3791 KASSERT(openerror == ENODEV || openerror == ENXIO, 3792 ("unexpected error %d in %s", openerror, __func__)); 3793 3794 /* 3795 * If the to-be-dup'd fd number is greater than the allowed number 3796 * of file descriptors, or the fd to be dup'd has already been 3797 * closed, then reject. 3798 */ 3799 FILEDESC_XLOCK(fdp); 3800 if ((fp = fget_noref(fdp, dfd)) == NULL) { 3801 FILEDESC_XUNLOCK(fdp); 3802 return (EBADF); 3803 } 3804 3805 error = fdalloc(td, 0, &indx); 3806 if (error != 0) { 3807 FILEDESC_XUNLOCK(fdp); 3808 return (error); 3809 } 3810 3811 /* 3812 * There are two cases of interest here. 3813 * 3814 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 3815 * 3816 * For ENXIO steal away the file structure from (dfd) and store it in 3817 * (indx). (dfd) is effectively closed by this operation. 3818 */ 3819 switch (openerror) { 3820 case ENODEV: 3821 /* 3822 * Check that the mode the file is being opened for is a 3823 * subset of the mode of the existing descriptor. 3824 */ 3825 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 3826 fdunused(fdp, indx); 3827 FILEDESC_XUNLOCK(fdp); 3828 return (EACCES); 3829 } 3830 if (!fhold(fp)) { 3831 fdunused(fdp, indx); 3832 FILEDESC_XUNLOCK(fdp); 3833 return (EBADF); 3834 } 3835 newfde = &fdp->fd_ofiles[indx]; 3836 oldfde = &fdp->fd_ofiles[dfd]; 3837 ioctls = filecaps_copy_prep(&oldfde->fde_caps); 3838 #ifdef CAPABILITIES 3839 seqc_write_begin(&newfde->fde_seqc); 3840 #endif 3841 fde_copy(oldfde, newfde); 3842 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps, 3843 ioctls); 3844 #ifdef CAPABILITIES 3845 seqc_write_end(&newfde->fde_seqc); 3846 #endif 3847 break; 3848 case ENXIO: 3849 /* 3850 * Steal away the file pointer from dfd and stuff it into indx. 3851 */ 3852 newfde = &fdp->fd_ofiles[indx]; 3853 oldfde = &fdp->fd_ofiles[dfd]; 3854 #ifdef CAPABILITIES 3855 seqc_write_begin(&oldfde->fde_seqc); 3856 seqc_write_begin(&newfde->fde_seqc); 3857 #endif 3858 fde_copy(oldfde, newfde); 3859 oldfde->fde_file = NULL; 3860 fdunused(fdp, dfd); 3861 #ifdef CAPABILITIES 3862 seqc_write_end(&newfde->fde_seqc); 3863 seqc_write_end(&oldfde->fde_seqc); 3864 #endif 3865 break; 3866 } 3867 FILEDESC_XUNLOCK(fdp); 3868 *indxp = indx; 3869 return (0); 3870 } 3871 3872 /* 3873 * This sysctl determines if we will allow a process to chroot(2) if it 3874 * has a directory open: 3875 * 0: disallowed for all processes. 3876 * 1: allowed for processes that were not already chroot(2)'ed. 3877 * 2: allowed for all processes. 3878 */ 3879 3880 static int chroot_allow_open_directories = 1; 3881 3882 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW, 3883 &chroot_allow_open_directories, 0, 3884 "Allow a process to chroot(2) if it has a directory open"); 3885 3886 /* 3887 * Helper function for raised chroot(2) security function: Refuse if 3888 * any filedescriptors are open directories. 3889 */ 3890 static int 3891 chroot_refuse_vdir_fds(struct filedesc *fdp) 3892 { 3893 struct vnode *vp; 3894 struct file *fp; 3895 int i; 3896 3897 FILEDESC_LOCK_ASSERT(fdp); 3898 3899 FILEDESC_FOREACH_FP(fdp, i, fp) { 3900 if (fp->f_type == DTYPE_VNODE) { 3901 vp = fp->f_vnode; 3902 if (vp->v_type == VDIR) 3903 return (EPERM); 3904 } 3905 } 3906 return (0); 3907 } 3908 3909 static void 3910 pwd_fill(struct pwd *oldpwd, struct pwd *newpwd) 3911 { 3912 3913 if (newpwd->pwd_cdir == NULL && oldpwd->pwd_cdir != NULL) { 3914 vrefact(oldpwd->pwd_cdir); 3915 newpwd->pwd_cdir = oldpwd->pwd_cdir; 3916 } 3917 3918 if (newpwd->pwd_rdir == NULL && oldpwd->pwd_rdir != NULL) { 3919 vrefact(oldpwd->pwd_rdir); 3920 newpwd->pwd_rdir = oldpwd->pwd_rdir; 3921 } 3922 3923 if (newpwd->pwd_jdir == NULL && oldpwd->pwd_jdir != NULL) { 3924 vrefact(oldpwd->pwd_jdir); 3925 newpwd->pwd_jdir = oldpwd->pwd_jdir; 3926 } 3927 3928 if (newpwd->pwd_adir == NULL && oldpwd->pwd_adir != NULL) { 3929 vrefact(oldpwd->pwd_adir); 3930 newpwd->pwd_adir = oldpwd->pwd_adir; 3931 } 3932 } 3933 3934 struct pwd * 3935 pwd_hold_pwddesc(struct pwddesc *pdp) 3936 { 3937 struct pwd *pwd; 3938 3939 PWDDESC_ASSERT_XLOCKED(pdp); 3940 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3941 if (pwd != NULL) 3942 refcount_acquire(&pwd->pwd_refcount); 3943 return (pwd); 3944 } 3945 3946 bool 3947 pwd_hold_smr(struct pwd *pwd) 3948 { 3949 3950 MPASS(pwd != NULL); 3951 if (__predict_true(refcount_acquire_if_not_zero(&pwd->pwd_refcount))) { 3952 return (true); 3953 } 3954 return (false); 3955 } 3956 3957 struct pwd * 3958 pwd_hold(struct thread *td) 3959 { 3960 struct pwddesc *pdp; 3961 struct pwd *pwd; 3962 3963 pdp = td->td_proc->p_pd; 3964 3965 vfs_smr_enter(); 3966 pwd = vfs_smr_entered_load(&pdp->pd_pwd); 3967 if (pwd_hold_smr(pwd)) { 3968 vfs_smr_exit(); 3969 return (pwd); 3970 } 3971 vfs_smr_exit(); 3972 PWDDESC_XLOCK(pdp); 3973 pwd = pwd_hold_pwddesc(pdp); 3974 MPASS(pwd != NULL); 3975 PWDDESC_XUNLOCK(pdp); 3976 return (pwd); 3977 } 3978 3979 struct pwd * 3980 pwd_hold_proc(struct proc *p) 3981 { 3982 struct pwddesc *pdp; 3983 struct pwd *pwd; 3984 3985 PROC_ASSERT_HELD(p); 3986 PROC_LOCK(p); 3987 pdp = pdhold(p); 3988 MPASS(pdp != NULL); 3989 PROC_UNLOCK(p); 3990 3991 PWDDESC_XLOCK(pdp); 3992 pwd = pwd_hold_pwddesc(pdp); 3993 MPASS(pwd != NULL); 3994 PWDDESC_XUNLOCK(pdp); 3995 pddrop(pdp); 3996 return (pwd); 3997 } 3998 3999 static struct pwd * 4000 pwd_alloc(void) 4001 { 4002 struct pwd *pwd; 4003 4004 pwd = uma_zalloc_smr(pwd_zone, M_WAITOK); 4005 bzero(pwd, sizeof(*pwd)); 4006 refcount_init(&pwd->pwd_refcount, 1); 4007 return (pwd); 4008 } 4009 4010 void 4011 pwd_drop(struct pwd *pwd) 4012 { 4013 4014 if (!refcount_release(&pwd->pwd_refcount)) 4015 return; 4016 4017 if (pwd->pwd_cdir != NULL) 4018 vrele(pwd->pwd_cdir); 4019 if (pwd->pwd_rdir != NULL) 4020 vrele(pwd->pwd_rdir); 4021 if (pwd->pwd_jdir != NULL) 4022 vrele(pwd->pwd_jdir); 4023 if (pwd->pwd_adir != NULL) 4024 vrele(pwd->pwd_adir); 4025 uma_zfree_smr(pwd_zone, pwd); 4026 } 4027 4028 /* 4029 * The caller is responsible for invoking priv_check() and 4030 * mac_vnode_check_chroot() to authorize this operation. 4031 */ 4032 int 4033 pwd_chroot(struct thread *td, struct vnode *vp) 4034 { 4035 struct pwddesc *pdp; 4036 struct filedesc *fdp; 4037 struct pwd *newpwd, *oldpwd; 4038 int error; 4039 4040 fdp = td->td_proc->p_fd; 4041 pdp = td->td_proc->p_pd; 4042 newpwd = pwd_alloc(); 4043 FILEDESC_SLOCK(fdp); 4044 PWDDESC_XLOCK(pdp); 4045 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4046 if (chroot_allow_open_directories == 0 || 4047 (chroot_allow_open_directories == 1 && 4048 oldpwd->pwd_rdir != rootvnode)) { 4049 error = chroot_refuse_vdir_fds(fdp); 4050 FILEDESC_SUNLOCK(fdp); 4051 if (error != 0) { 4052 PWDDESC_XUNLOCK(pdp); 4053 pwd_drop(newpwd); 4054 return (error); 4055 } 4056 } else { 4057 FILEDESC_SUNLOCK(fdp); 4058 } 4059 4060 vrefact(vp); 4061 newpwd->pwd_rdir = vp; 4062 vrefact(vp); 4063 newpwd->pwd_adir = vp; 4064 if (oldpwd->pwd_jdir == NULL) { 4065 vrefact(vp); 4066 newpwd->pwd_jdir = vp; 4067 } 4068 pwd_fill(oldpwd, newpwd); 4069 pwd_set(pdp, newpwd); 4070 PWDDESC_XUNLOCK(pdp); 4071 pwd_drop(oldpwd); 4072 return (0); 4073 } 4074 4075 void 4076 pwd_chdir(struct thread *td, struct vnode *vp) 4077 { 4078 struct pwddesc *pdp; 4079 struct pwd *newpwd, *oldpwd; 4080 4081 VNPASS(vp->v_usecount > 0, vp); 4082 4083 newpwd = pwd_alloc(); 4084 pdp = td->td_proc->p_pd; 4085 PWDDESC_XLOCK(pdp); 4086 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4087 newpwd->pwd_cdir = vp; 4088 pwd_fill(oldpwd, newpwd); 4089 pwd_set(pdp, newpwd); 4090 PWDDESC_XUNLOCK(pdp); 4091 pwd_drop(oldpwd); 4092 } 4093 4094 /* 4095 * Process is transitioning to/from a non-native ABI. 4096 */ 4097 void 4098 pwd_altroot(struct thread *td, struct vnode *altroot_vp) 4099 { 4100 struct pwddesc *pdp; 4101 struct pwd *newpwd, *oldpwd; 4102 4103 newpwd = pwd_alloc(); 4104 pdp = td->td_proc->p_pd; 4105 PWDDESC_XLOCK(pdp); 4106 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4107 if (altroot_vp != NULL) { 4108 /* 4109 * Native process to a non-native ABI. 4110 */ 4111 4112 vrefact(altroot_vp); 4113 newpwd->pwd_adir = altroot_vp; 4114 } else { 4115 /* 4116 * Non-native process to the native ABI. 4117 */ 4118 4119 vrefact(oldpwd->pwd_rdir); 4120 newpwd->pwd_adir = oldpwd->pwd_rdir; 4121 } 4122 pwd_fill(oldpwd, newpwd); 4123 pwd_set(pdp, newpwd); 4124 PWDDESC_XUNLOCK(pdp); 4125 pwd_drop(oldpwd); 4126 } 4127 4128 /* 4129 * jail_attach(2) changes both root and working directories. 4130 */ 4131 int 4132 pwd_chroot_chdir(struct thread *td, struct vnode *vp) 4133 { 4134 struct pwddesc *pdp; 4135 struct filedesc *fdp; 4136 struct pwd *newpwd, *oldpwd; 4137 int error; 4138 4139 fdp = td->td_proc->p_fd; 4140 pdp = td->td_proc->p_pd; 4141 newpwd = pwd_alloc(); 4142 FILEDESC_SLOCK(fdp); 4143 PWDDESC_XLOCK(pdp); 4144 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4145 error = chroot_refuse_vdir_fds(fdp); 4146 FILEDESC_SUNLOCK(fdp); 4147 if (error != 0) { 4148 PWDDESC_XUNLOCK(pdp); 4149 pwd_drop(newpwd); 4150 return (error); 4151 } 4152 4153 vrefact(vp); 4154 newpwd->pwd_rdir = vp; 4155 vrefact(vp); 4156 newpwd->pwd_cdir = vp; 4157 if (oldpwd->pwd_jdir == NULL) { 4158 vrefact(vp); 4159 newpwd->pwd_jdir = vp; 4160 } 4161 vrefact(vp); 4162 newpwd->pwd_adir = vp; 4163 pwd_fill(oldpwd, newpwd); 4164 pwd_set(pdp, newpwd); 4165 PWDDESC_XUNLOCK(pdp); 4166 pwd_drop(oldpwd); 4167 return (0); 4168 } 4169 4170 void 4171 pwd_ensure_dirs(void) 4172 { 4173 struct pwddesc *pdp; 4174 struct pwd *oldpwd, *newpwd; 4175 4176 pdp = curproc->p_pd; 4177 PWDDESC_XLOCK(pdp); 4178 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4179 if (oldpwd->pwd_cdir != NULL && oldpwd->pwd_rdir != NULL && 4180 oldpwd->pwd_adir != NULL) { 4181 PWDDESC_XUNLOCK(pdp); 4182 return; 4183 } 4184 PWDDESC_XUNLOCK(pdp); 4185 4186 newpwd = pwd_alloc(); 4187 PWDDESC_XLOCK(pdp); 4188 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4189 pwd_fill(oldpwd, newpwd); 4190 if (newpwd->pwd_cdir == NULL) { 4191 vrefact(rootvnode); 4192 newpwd->pwd_cdir = rootvnode; 4193 } 4194 if (newpwd->pwd_rdir == NULL) { 4195 vrefact(rootvnode); 4196 newpwd->pwd_rdir = rootvnode; 4197 } 4198 if (newpwd->pwd_adir == NULL) { 4199 vrefact(rootvnode); 4200 newpwd->pwd_adir = rootvnode; 4201 } 4202 pwd_set(pdp, newpwd); 4203 PWDDESC_XUNLOCK(pdp); 4204 pwd_drop(oldpwd); 4205 } 4206 4207 void 4208 pwd_set_rootvnode(void) 4209 { 4210 struct pwddesc *pdp; 4211 struct pwd *oldpwd, *newpwd; 4212 4213 pdp = curproc->p_pd; 4214 4215 newpwd = pwd_alloc(); 4216 PWDDESC_XLOCK(pdp); 4217 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4218 vrefact(rootvnode); 4219 newpwd->pwd_cdir = rootvnode; 4220 vrefact(rootvnode); 4221 newpwd->pwd_rdir = rootvnode; 4222 vrefact(rootvnode); 4223 newpwd->pwd_adir = rootvnode; 4224 pwd_fill(oldpwd, newpwd); 4225 pwd_set(pdp, newpwd); 4226 PWDDESC_XUNLOCK(pdp); 4227 pwd_drop(oldpwd); 4228 } 4229 4230 /* 4231 * Scan all active processes and prisons to see if any of them have a current 4232 * or root directory of `olddp'. If so, replace them with the new mount point. 4233 */ 4234 void 4235 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 4236 { 4237 struct pwddesc *pdp; 4238 struct pwd *newpwd, *oldpwd; 4239 struct prison *pr; 4240 struct proc *p; 4241 int nrele; 4242 4243 if (vrefcnt(olddp) == 1) 4244 return; 4245 nrele = 0; 4246 newpwd = pwd_alloc(); 4247 sx_slock(&allproc_lock); 4248 FOREACH_PROC_IN_SYSTEM(p) { 4249 PROC_LOCK(p); 4250 pdp = pdhold(p); 4251 PROC_UNLOCK(p); 4252 if (pdp == NULL) 4253 continue; 4254 PWDDESC_XLOCK(pdp); 4255 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4256 if (oldpwd == NULL || 4257 (oldpwd->pwd_cdir != olddp && 4258 oldpwd->pwd_rdir != olddp && 4259 oldpwd->pwd_jdir != olddp && 4260 oldpwd->pwd_adir != olddp)) { 4261 PWDDESC_XUNLOCK(pdp); 4262 pddrop(pdp); 4263 continue; 4264 } 4265 if (oldpwd->pwd_cdir == olddp) { 4266 vrefact(newdp); 4267 newpwd->pwd_cdir = newdp; 4268 } 4269 if (oldpwd->pwd_rdir == olddp) { 4270 vrefact(newdp); 4271 newpwd->pwd_rdir = newdp; 4272 } 4273 if (oldpwd->pwd_jdir == olddp) { 4274 vrefact(newdp); 4275 newpwd->pwd_jdir = newdp; 4276 } 4277 if (oldpwd->pwd_adir == olddp) { 4278 vrefact(newdp); 4279 newpwd->pwd_adir = newdp; 4280 } 4281 pwd_fill(oldpwd, newpwd); 4282 pwd_set(pdp, newpwd); 4283 PWDDESC_XUNLOCK(pdp); 4284 pwd_drop(oldpwd); 4285 pddrop(pdp); 4286 newpwd = pwd_alloc(); 4287 } 4288 sx_sunlock(&allproc_lock); 4289 pwd_drop(newpwd); 4290 if (rootvnode == olddp) { 4291 vrefact(newdp); 4292 rootvnode = newdp; 4293 nrele++; 4294 } 4295 mtx_lock(&prison0.pr_mtx); 4296 if (prison0.pr_root == olddp) { 4297 vrefact(newdp); 4298 prison0.pr_root = newdp; 4299 nrele++; 4300 } 4301 mtx_unlock(&prison0.pr_mtx); 4302 sx_slock(&allprison_lock); 4303 TAILQ_FOREACH(pr, &allprison, pr_list) { 4304 mtx_lock(&pr->pr_mtx); 4305 if (pr->pr_root == olddp) { 4306 vrefact(newdp); 4307 pr->pr_root = newdp; 4308 nrele++; 4309 } 4310 mtx_unlock(&pr->pr_mtx); 4311 } 4312 sx_sunlock(&allprison_lock); 4313 while (nrele--) 4314 vrele(olddp); 4315 } 4316 4317 int 4318 descrip_check_write_mp(struct filedesc *fdp, struct mount *mp) 4319 { 4320 struct file *fp; 4321 struct vnode *vp; 4322 int error, i; 4323 4324 error = 0; 4325 FILEDESC_SLOCK(fdp); 4326 FILEDESC_FOREACH_FP(fdp, i, fp) { 4327 if (fp->f_type != DTYPE_VNODE || 4328 (atomic_load_int(&fp->f_flag) & FWRITE) == 0) 4329 continue; 4330 vp = fp->f_vnode; 4331 if (vp->v_mount == mp) { 4332 error = EDEADLK; 4333 break; 4334 } 4335 } 4336 FILEDESC_SUNLOCK(fdp); 4337 return (error); 4338 } 4339 4340 struct filedesc_to_leader * 4341 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, 4342 struct proc *leader) 4343 { 4344 struct filedesc_to_leader *fdtol; 4345 4346 fdtol = malloc(sizeof(struct filedesc_to_leader), 4347 M_FILEDESC_TO_LEADER, M_WAITOK); 4348 fdtol->fdl_refcount = 1; 4349 fdtol->fdl_holdcount = 0; 4350 fdtol->fdl_wakeup = 0; 4351 fdtol->fdl_leader = leader; 4352 if (old != NULL) { 4353 FILEDESC_XLOCK(fdp); 4354 fdtol->fdl_next = old->fdl_next; 4355 fdtol->fdl_prev = old; 4356 old->fdl_next = fdtol; 4357 fdtol->fdl_next->fdl_prev = fdtol; 4358 FILEDESC_XUNLOCK(fdp); 4359 } else { 4360 fdtol->fdl_next = fdtol; 4361 fdtol->fdl_prev = fdtol; 4362 } 4363 return (fdtol); 4364 } 4365 4366 struct filedesc_to_leader * 4367 filedesc_to_leader_share(struct filedesc_to_leader *fdtol, struct filedesc *fdp) 4368 { 4369 FILEDESC_XLOCK(fdp); 4370 fdtol->fdl_refcount++; 4371 FILEDESC_XUNLOCK(fdp); 4372 return (fdtol); 4373 } 4374 4375 static int 4376 filedesc_nfiles(struct filedesc *fdp) 4377 { 4378 NDSLOTTYPE *map; 4379 int count, off, minoff; 4380 4381 if (fdp == NULL) 4382 return (0); 4383 count = 0; 4384 FILEDESC_SLOCK(fdp); 4385 map = fdp->fd_map; 4386 off = NDSLOT(fdp->fd_nfiles - 1); 4387 for (minoff = NDSLOT(0); off >= minoff; --off) 4388 count += bitcountl(map[off]); 4389 FILEDESC_SUNLOCK(fdp); 4390 return (count); 4391 } 4392 4393 int 4394 proc_nfiles(struct proc *p) 4395 { 4396 struct filedesc *fdp; 4397 int res; 4398 4399 PROC_LOCK(p); 4400 fdp = fdhold(p); 4401 PROC_UNLOCK(p); 4402 res = filedesc_nfiles(fdp); 4403 fddrop(fdp); 4404 return (res); 4405 } 4406 4407 static int 4408 sysctl_kern_proc_nfds(SYSCTL_HANDLER_ARGS) 4409 { 4410 u_int namelen; 4411 int count; 4412 4413 namelen = arg2; 4414 if (namelen != 1) 4415 return (EINVAL); 4416 4417 if (*(int *)arg1 != 0) 4418 return (EINVAL); 4419 4420 count = filedesc_nfiles(curproc->p_fd); 4421 return (SYSCTL_OUT(req, &count, sizeof(count))); 4422 } 4423 4424 static SYSCTL_NODE(_kern_proc, KERN_PROC_NFDS, nfds, 4425 CTLFLAG_RD|CTLFLAG_CAPRD|CTLFLAG_MPSAFE, sysctl_kern_proc_nfds, 4426 "Number of open file descriptors"); 4427 4428 /* 4429 * Get file structures globally. 4430 */ 4431 static int 4432 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 4433 { 4434 struct xfile xf; 4435 struct filedesc *fdp; 4436 struct file *fp; 4437 struct proc *p; 4438 int error, n; 4439 4440 error = sysctl_wire_old_buffer(req, 0); 4441 if (error != 0) 4442 return (error); 4443 if (req->oldptr == NULL) { 4444 n = 0; 4445 sx_slock(&allproc_lock); 4446 FOREACH_PROC_IN_SYSTEM(p) { 4447 PROC_LOCK(p); 4448 if (p->p_state == PRS_NEW) { 4449 PROC_UNLOCK(p); 4450 continue; 4451 } 4452 fdp = fdhold(p); 4453 PROC_UNLOCK(p); 4454 if (fdp == NULL) 4455 continue; 4456 /* overestimates sparse tables. */ 4457 n += fdp->fd_nfiles; 4458 fddrop(fdp); 4459 } 4460 sx_sunlock(&allproc_lock); 4461 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 4462 } 4463 error = 0; 4464 bzero(&xf, sizeof(xf)); 4465 xf.xf_size = sizeof(xf); 4466 sx_slock(&allproc_lock); 4467 FOREACH_PROC_IN_SYSTEM(p) { 4468 PROC_LOCK(p); 4469 if (p->p_state == PRS_NEW) { 4470 PROC_UNLOCK(p); 4471 continue; 4472 } 4473 if (p_cansee(req->td, p) != 0) { 4474 PROC_UNLOCK(p); 4475 continue; 4476 } 4477 xf.xf_pid = p->p_pid; 4478 xf.xf_uid = p->p_ucred->cr_uid; 4479 fdp = fdhold(p); 4480 PROC_UNLOCK(p); 4481 if (fdp == NULL) 4482 continue; 4483 FILEDESC_SLOCK(fdp); 4484 if (refcount_load(&fdp->fd_refcnt) == 0) 4485 goto nextproc; 4486 FILEDESC_FOREACH_FP(fdp, n, fp) { 4487 xf.xf_fd = n; 4488 xf.xf_file = (uintptr_t)fp; 4489 xf.xf_data = (uintptr_t)fp->f_data; 4490 xf.xf_vnode = (uintptr_t)fp->f_vnode; 4491 xf.xf_type = (uintptr_t)fp->f_type; 4492 xf.xf_count = refcount_load(&fp->f_count); 4493 xf.xf_msgcount = 0; 4494 xf.xf_offset = foffset_get(fp); 4495 xf.xf_flag = fp->f_flag; 4496 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 4497 4498 /* 4499 * There is no need to re-check the fdtable refcount 4500 * here since the filedesc lock is not dropped in the 4501 * loop body. 4502 */ 4503 if (error != 0) 4504 break; 4505 } 4506 nextproc: 4507 FILEDESC_SUNLOCK(fdp); 4508 fddrop(fdp); 4509 if (error) 4510 break; 4511 } 4512 sx_sunlock(&allproc_lock); 4513 return (error); 4514 } 4515 4516 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 4517 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 4518 4519 #ifdef KINFO_FILE_SIZE 4520 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 4521 #endif 4522 4523 static int 4524 xlate_fflags(int fflags) 4525 { 4526 static const struct { 4527 int fflag; 4528 int kf_fflag; 4529 } fflags_table[] = { 4530 { FAPPEND, KF_FLAG_APPEND }, 4531 { FASYNC, KF_FLAG_ASYNC }, 4532 { FFSYNC, KF_FLAG_FSYNC }, 4533 { FHASLOCK, KF_FLAG_HASLOCK }, 4534 { FNONBLOCK, KF_FLAG_NONBLOCK }, 4535 { FREAD, KF_FLAG_READ }, 4536 { FWRITE, KF_FLAG_WRITE }, 4537 { O_CREAT, KF_FLAG_CREAT }, 4538 { O_DIRECT, KF_FLAG_DIRECT }, 4539 { O_EXCL, KF_FLAG_EXCL }, 4540 { O_EXEC, KF_FLAG_EXEC }, 4541 { O_EXLOCK, KF_FLAG_EXLOCK }, 4542 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 4543 { O_SHLOCK, KF_FLAG_SHLOCK }, 4544 { O_TRUNC, KF_FLAG_TRUNC } 4545 }; 4546 unsigned int i; 4547 int kflags; 4548 4549 kflags = 0; 4550 for (i = 0; i < nitems(fflags_table); i++) 4551 if (fflags & fflags_table[i].fflag) 4552 kflags |= fflags_table[i].kf_fflag; 4553 return (kflags); 4554 } 4555 4556 /* Trim unused data from kf_path by truncating the structure size. */ 4557 void 4558 pack_kinfo(struct kinfo_file *kif) 4559 { 4560 4561 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 4562 strlen(kif->kf_path) + 1; 4563 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 4564 } 4565 4566 static void 4567 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp, 4568 struct kinfo_file *kif, struct filedesc *fdp, int flags) 4569 { 4570 int error; 4571 4572 bzero(kif, sizeof(*kif)); 4573 4574 /* Set a default type to allow for empty fill_kinfo() methods. */ 4575 kif->kf_type = KF_TYPE_UNKNOWN; 4576 kif->kf_flags = xlate_fflags(fp->f_flag); 4577 if (rightsp != NULL) 4578 kif->kf_cap_rights = *rightsp; 4579 else 4580 cap_rights_init_zero(&kif->kf_cap_rights); 4581 kif->kf_fd = fd; 4582 kif->kf_ref_count = refcount_load(&fp->f_count); 4583 kif->kf_offset = foffset_get(fp); 4584 4585 /* 4586 * This may drop the filedesc lock, so the 'fp' cannot be 4587 * accessed after this call. 4588 */ 4589 error = fo_fill_kinfo(fp, kif, fdp); 4590 if (error == 0) 4591 kif->kf_status |= KF_ATTR_VALID; 4592 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 4593 pack_kinfo(kif); 4594 else 4595 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 4596 } 4597 4598 static void 4599 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags, 4600 struct kinfo_file *kif, int flags) 4601 { 4602 int error; 4603 4604 bzero(kif, sizeof(*kif)); 4605 4606 kif->kf_type = KF_TYPE_VNODE; 4607 error = vn_fill_kinfo_vnode(vp, kif); 4608 if (error == 0) 4609 kif->kf_status |= KF_ATTR_VALID; 4610 kif->kf_flags = xlate_fflags(fflags); 4611 cap_rights_init_zero(&kif->kf_cap_rights); 4612 kif->kf_fd = fd; 4613 kif->kf_ref_count = -1; 4614 kif->kf_offset = -1; 4615 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 4616 pack_kinfo(kif); 4617 else 4618 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 4619 vrele(vp); 4620 } 4621 4622 struct export_fd_buf { 4623 struct filedesc *fdp; 4624 struct pwddesc *pdp; 4625 struct sbuf *sb; 4626 ssize_t remainder; 4627 struct kinfo_file kif; 4628 int flags; 4629 }; 4630 4631 static int 4632 export_kinfo_to_sb(struct export_fd_buf *efbuf) 4633 { 4634 struct kinfo_file *kif; 4635 4636 kif = &efbuf->kif; 4637 if (efbuf->remainder != -1) { 4638 if (efbuf->remainder < kif->kf_structsize) 4639 return (ENOMEM); 4640 efbuf->remainder -= kif->kf_structsize; 4641 } 4642 if (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) != 0) 4643 return (sbuf_error(efbuf->sb)); 4644 return (0); 4645 } 4646 4647 static int 4648 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp, 4649 struct export_fd_buf *efbuf) 4650 { 4651 int error; 4652 4653 if (efbuf->remainder == 0) 4654 return (ENOMEM); 4655 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp, 4656 efbuf->flags); 4657 FILEDESC_SUNLOCK(efbuf->fdp); 4658 error = export_kinfo_to_sb(efbuf); 4659 FILEDESC_SLOCK(efbuf->fdp); 4660 return (error); 4661 } 4662 4663 static int 4664 export_vnode_to_sb(struct vnode *vp, int fd, int fflags, 4665 struct export_fd_buf *efbuf) 4666 { 4667 int error; 4668 4669 if (efbuf->remainder == 0) 4670 return (ENOMEM); 4671 if (efbuf->pdp != NULL) 4672 PWDDESC_XUNLOCK(efbuf->pdp); 4673 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif, efbuf->flags); 4674 error = export_kinfo_to_sb(efbuf); 4675 if (efbuf->pdp != NULL) 4676 PWDDESC_XLOCK(efbuf->pdp); 4677 return (error); 4678 } 4679 4680 /* 4681 * Store a process file descriptor information to sbuf. 4682 * 4683 * Takes a locked proc as argument, and returns with the proc unlocked. 4684 */ 4685 int 4686 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen, 4687 int flags) 4688 { 4689 struct file *fp; 4690 struct filedesc *fdp; 4691 struct pwddesc *pdp; 4692 struct export_fd_buf *efbuf; 4693 struct vnode *cttyvp, *textvp, *tracevp; 4694 struct pwd *pwd; 4695 int error, i; 4696 cap_rights_t rights; 4697 4698 PROC_LOCK_ASSERT(p, MA_OWNED); 4699 4700 /* ktrace vnode */ 4701 tracevp = ktr_get_tracevp(p, true); 4702 /* text vnode */ 4703 textvp = p->p_textvp; 4704 if (textvp != NULL) 4705 vrefact(textvp); 4706 /* Controlling tty. */ 4707 cttyvp = NULL; 4708 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 4709 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 4710 if (cttyvp != NULL) 4711 vrefact(cttyvp); 4712 } 4713 fdp = fdhold(p); 4714 pdp = pdhold(p); 4715 PROC_UNLOCK(p); 4716 4717 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 4718 efbuf->fdp = NULL; 4719 efbuf->pdp = NULL; 4720 efbuf->sb = sb; 4721 efbuf->remainder = maxlen; 4722 efbuf->flags = flags; 4723 4724 error = 0; 4725 if (tracevp != NULL) 4726 error = export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE, 4727 FREAD | FWRITE, efbuf); 4728 if (error == 0 && textvp != NULL) 4729 error = export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD, 4730 efbuf); 4731 if (error == 0 && cttyvp != NULL) 4732 error = export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY, 4733 FREAD | FWRITE, efbuf); 4734 if (error != 0 || pdp == NULL || fdp == NULL) 4735 goto fail; 4736 efbuf->fdp = fdp; 4737 efbuf->pdp = pdp; 4738 PWDDESC_XLOCK(pdp); 4739 pwd = pwd_hold_pwddesc(pdp); 4740 if (pwd != NULL) { 4741 /* working directory */ 4742 if (pwd->pwd_cdir != NULL) { 4743 vrefact(pwd->pwd_cdir); 4744 error = export_vnode_to_sb(pwd->pwd_cdir, 4745 KF_FD_TYPE_CWD, FREAD, efbuf); 4746 } 4747 /* root directory */ 4748 if (error == 0 && pwd->pwd_rdir != NULL) { 4749 vrefact(pwd->pwd_rdir); 4750 error = export_vnode_to_sb(pwd->pwd_rdir, 4751 KF_FD_TYPE_ROOT, FREAD, efbuf); 4752 } 4753 /* jail directory */ 4754 if (error == 0 && pwd->pwd_jdir != NULL) { 4755 vrefact(pwd->pwd_jdir); 4756 error = export_vnode_to_sb(pwd->pwd_jdir, 4757 KF_FD_TYPE_JAIL, FREAD, efbuf); 4758 } 4759 } 4760 PWDDESC_XUNLOCK(pdp); 4761 if (error != 0) 4762 goto fail; 4763 if (pwd != NULL) 4764 pwd_drop(pwd); 4765 FILEDESC_SLOCK(fdp); 4766 if (refcount_load(&fdp->fd_refcnt) == 0) 4767 goto skip; 4768 FILEDESC_FOREACH_FP(fdp, i, fp) { 4769 #ifdef CAPABILITIES 4770 rights = *cap_rights(fdp, i); 4771 #else /* !CAPABILITIES */ 4772 rights = cap_no_rights; 4773 #endif 4774 /* 4775 * Create sysctl entry. It is OK to drop the filedesc 4776 * lock inside of export_file_to_sb() as we will 4777 * re-validate and re-evaluate its properties when the 4778 * loop continues. 4779 */ 4780 error = export_file_to_sb(fp, i, &rights, efbuf); 4781 if (error != 0 || refcount_load(&fdp->fd_refcnt) == 0) 4782 break; 4783 } 4784 skip: 4785 FILEDESC_SUNLOCK(fdp); 4786 fail: 4787 if (fdp != NULL) 4788 fddrop(fdp); 4789 if (pdp != NULL) 4790 pddrop(pdp); 4791 free(efbuf, M_TEMP); 4792 return (error); 4793 } 4794 4795 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 4796 4797 /* 4798 * Get per-process file descriptors for use by procstat(1), et al. 4799 */ 4800 static int 4801 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 4802 { 4803 struct sbuf sb; 4804 struct proc *p; 4805 ssize_t maxlen; 4806 u_int namelen; 4807 int error, error2, *name; 4808 4809 namelen = arg2; 4810 if (namelen != 1) 4811 return (EINVAL); 4812 4813 name = (int *)arg1; 4814 4815 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 4816 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 4817 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 4818 if (error != 0) { 4819 sbuf_delete(&sb); 4820 return (error); 4821 } 4822 maxlen = req->oldptr != NULL ? req->oldlen : -1; 4823 error = kern_proc_filedesc_out(p, &sb, maxlen, 4824 KERN_FILEDESC_PACK_KINFO); 4825 error2 = sbuf_finish(&sb); 4826 sbuf_delete(&sb); 4827 return (error != 0 ? error : error2); 4828 } 4829 4830 #ifdef COMPAT_FREEBSD7 4831 #ifdef KINFO_OFILE_SIZE 4832 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 4833 #endif 4834 4835 static void 4836 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif) 4837 { 4838 4839 okif->kf_structsize = sizeof(*okif); 4840 okif->kf_type = kif->kf_type; 4841 okif->kf_fd = kif->kf_fd; 4842 okif->kf_ref_count = kif->kf_ref_count; 4843 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE | 4844 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK | 4845 KF_FLAG_DIRECT | KF_FLAG_HASLOCK); 4846 okif->kf_offset = kif->kf_offset; 4847 if (kif->kf_type == KF_TYPE_VNODE) 4848 okif->kf_vnode_type = kif->kf_un.kf_file.kf_file_type; 4849 else 4850 okif->kf_vnode_type = KF_VTYPE_VNON; 4851 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path)); 4852 if (kif->kf_type == KF_TYPE_SOCKET) { 4853 okif->kf_sock_domain = kif->kf_un.kf_sock.kf_sock_domain0; 4854 okif->kf_sock_type = kif->kf_un.kf_sock.kf_sock_type0; 4855 okif->kf_sock_protocol = kif->kf_un.kf_sock.kf_sock_protocol0; 4856 okif->kf_sa_local = kif->kf_un.kf_sock.kf_sa_local; 4857 okif->kf_sa_peer = kif->kf_un.kf_sock.kf_sa_peer; 4858 } else { 4859 okif->kf_sa_local.ss_family = AF_UNSPEC; 4860 okif->kf_sa_peer.ss_family = AF_UNSPEC; 4861 } 4862 } 4863 4864 static int 4865 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif, 4866 struct kinfo_ofile *okif, struct pwddesc *pdp, struct sysctl_req *req) 4867 { 4868 int error; 4869 4870 vrefact(vp); 4871 PWDDESC_XUNLOCK(pdp); 4872 export_vnode_to_kinfo(vp, type, 0, kif, KERN_FILEDESC_PACK_KINFO); 4873 kinfo_to_okinfo(kif, okif); 4874 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 4875 PWDDESC_XLOCK(pdp); 4876 return (error); 4877 } 4878 4879 /* 4880 * Get per-process file descriptors for use by procstat(1), et al. 4881 */ 4882 static int 4883 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 4884 { 4885 struct kinfo_ofile *okif; 4886 struct kinfo_file *kif; 4887 struct filedesc *fdp; 4888 struct pwddesc *pdp; 4889 struct pwd *pwd; 4890 u_int namelen; 4891 int error, i, *name; 4892 struct file *fp; 4893 struct proc *p; 4894 4895 namelen = arg2; 4896 if (namelen != 1) 4897 return (EINVAL); 4898 4899 name = (int *)arg1; 4900 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 4901 if (error != 0) 4902 return (error); 4903 fdp = fdhold(p); 4904 if (fdp != NULL) 4905 pdp = pdhold(p); 4906 PROC_UNLOCK(p); 4907 if (fdp == NULL || pdp == NULL) { 4908 if (fdp != NULL) 4909 fddrop(fdp); 4910 return (ENOENT); 4911 } 4912 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 4913 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK); 4914 PWDDESC_XLOCK(pdp); 4915 pwd = pwd_hold_pwddesc(pdp); 4916 if (pwd != NULL) { 4917 if (pwd->pwd_cdir != NULL) 4918 export_vnode_for_osysctl(pwd->pwd_cdir, KF_FD_TYPE_CWD, kif, 4919 okif, pdp, req); 4920 if (pwd->pwd_rdir != NULL) 4921 export_vnode_for_osysctl(pwd->pwd_rdir, KF_FD_TYPE_ROOT, kif, 4922 okif, pdp, req); 4923 if (pwd->pwd_jdir != NULL) 4924 export_vnode_for_osysctl(pwd->pwd_jdir, KF_FD_TYPE_JAIL, kif, 4925 okif, pdp, req); 4926 } 4927 PWDDESC_XUNLOCK(pdp); 4928 if (pwd != NULL) 4929 pwd_drop(pwd); 4930 FILEDESC_SLOCK(fdp); 4931 if (refcount_load(&fdp->fd_refcnt) == 0) 4932 goto skip; 4933 FILEDESC_FOREACH_FP(fdp, i, fp) { 4934 export_file_to_kinfo(fp, i, NULL, kif, fdp, 4935 KERN_FILEDESC_PACK_KINFO); 4936 FILEDESC_SUNLOCK(fdp); 4937 kinfo_to_okinfo(kif, okif); 4938 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 4939 FILEDESC_SLOCK(fdp); 4940 if (error != 0 || refcount_load(&fdp->fd_refcnt) == 0) 4941 break; 4942 } 4943 skip: 4944 FILEDESC_SUNLOCK(fdp); 4945 fddrop(fdp); 4946 pddrop(pdp); 4947 free(kif, M_TEMP); 4948 free(okif, M_TEMP); 4949 return (0); 4950 } 4951 4952 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 4953 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 4954 "Process ofiledesc entries"); 4955 #endif /* COMPAT_FREEBSD7 */ 4956 4957 int 4958 vntype_to_kinfo(int vtype) 4959 { 4960 struct { 4961 int vtype; 4962 int kf_vtype; 4963 } vtypes_table[] = { 4964 { VBAD, KF_VTYPE_VBAD }, 4965 { VBLK, KF_VTYPE_VBLK }, 4966 { VCHR, KF_VTYPE_VCHR }, 4967 { VDIR, KF_VTYPE_VDIR }, 4968 { VFIFO, KF_VTYPE_VFIFO }, 4969 { VLNK, KF_VTYPE_VLNK }, 4970 { VNON, KF_VTYPE_VNON }, 4971 { VREG, KF_VTYPE_VREG }, 4972 { VSOCK, KF_VTYPE_VSOCK } 4973 }; 4974 unsigned int i; 4975 4976 /* 4977 * Perform vtype translation. 4978 */ 4979 for (i = 0; i < nitems(vtypes_table); i++) 4980 if (vtypes_table[i].vtype == vtype) 4981 return (vtypes_table[i].kf_vtype); 4982 4983 return (KF_VTYPE_UNKNOWN); 4984 } 4985 4986 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 4987 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 4988 "Process filedesc entries"); 4989 4990 /* 4991 * Store a process current working directory information to sbuf. 4992 * 4993 * Takes a locked proc as argument, and returns with the proc unlocked. 4994 */ 4995 int 4996 kern_proc_cwd_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 4997 { 4998 struct pwddesc *pdp; 4999 struct pwd *pwd; 5000 struct export_fd_buf *efbuf; 5001 struct vnode *cdir; 5002 int error; 5003 5004 PROC_LOCK_ASSERT(p, MA_OWNED); 5005 5006 pdp = pdhold(p); 5007 PROC_UNLOCK(p); 5008 if (pdp == NULL) 5009 return (EINVAL); 5010 5011 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 5012 efbuf->fdp = NULL; 5013 efbuf->pdp = pdp; 5014 efbuf->sb = sb; 5015 efbuf->remainder = maxlen; 5016 efbuf->flags = 0; 5017 5018 PWDDESC_XLOCK(pdp); 5019 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 5020 cdir = pwd->pwd_cdir; 5021 if (cdir == NULL) { 5022 error = EINVAL; 5023 } else { 5024 vrefact(cdir); 5025 error = export_vnode_to_sb(cdir, KF_FD_TYPE_CWD, FREAD, efbuf); 5026 } 5027 PWDDESC_XUNLOCK(pdp); 5028 pddrop(pdp); 5029 free(efbuf, M_TEMP); 5030 return (error); 5031 } 5032 5033 /* 5034 * Get per-process current working directory. 5035 */ 5036 static int 5037 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS) 5038 { 5039 struct sbuf sb; 5040 struct proc *p; 5041 ssize_t maxlen; 5042 u_int namelen; 5043 int error, error2, *name; 5044 5045 namelen = arg2; 5046 if (namelen != 1) 5047 return (EINVAL); 5048 5049 name = (int *)arg1; 5050 5051 sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file), req); 5052 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 5053 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 5054 if (error != 0) { 5055 sbuf_delete(&sb); 5056 return (error); 5057 } 5058 maxlen = req->oldptr != NULL ? req->oldlen : -1; 5059 error = kern_proc_cwd_out(p, &sb, maxlen); 5060 error2 = sbuf_finish(&sb); 5061 sbuf_delete(&sb); 5062 return (error != 0 ? error : error2); 5063 } 5064 5065 static SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD|CTLFLAG_MPSAFE, 5066 sysctl_kern_proc_cwd, "Process current working directory"); 5067 5068 #ifdef DDB 5069 /* 5070 * For the purposes of debugging, generate a human-readable string for the 5071 * file type. 5072 */ 5073 static const char * 5074 file_type_to_name(short type) 5075 { 5076 5077 switch (type) { 5078 case 0: 5079 return ("zero"); 5080 case DTYPE_VNODE: 5081 return ("vnode"); 5082 case DTYPE_SOCKET: 5083 return ("socket"); 5084 case DTYPE_PIPE: 5085 return ("pipe"); 5086 case DTYPE_FIFO: 5087 return ("fifo"); 5088 case DTYPE_KQUEUE: 5089 return ("kqueue"); 5090 case DTYPE_CRYPTO: 5091 return ("crypto"); 5092 case DTYPE_MQUEUE: 5093 return ("mqueue"); 5094 case DTYPE_SHM: 5095 return ("shm"); 5096 case DTYPE_SEM: 5097 return ("ksem"); 5098 case DTYPE_PTS: 5099 return ("pts"); 5100 case DTYPE_DEV: 5101 return ("dev"); 5102 case DTYPE_PROCDESC: 5103 return ("proc"); 5104 case DTYPE_EVENTFD: 5105 return ("eventfd"); 5106 case DTYPE_TIMERFD: 5107 return ("timerfd"); 5108 default: 5109 return ("unkn"); 5110 } 5111 } 5112 5113 /* 5114 * For the purposes of debugging, identify a process (if any, perhaps one of 5115 * many) that references the passed file in its file descriptor array. Return 5116 * NULL if none. 5117 */ 5118 static struct proc * 5119 file_to_first_proc(struct file *fp) 5120 { 5121 struct filedesc *fdp; 5122 struct proc *p; 5123 int n; 5124 5125 FOREACH_PROC_IN_SYSTEM(p) { 5126 if (p->p_state == PRS_NEW) 5127 continue; 5128 fdp = p->p_fd; 5129 if (fdp == NULL) 5130 continue; 5131 for (n = 0; n < fdp->fd_nfiles; n++) { 5132 if (fp == fdp->fd_ofiles[n].fde_file) 5133 return (p); 5134 } 5135 } 5136 return (NULL); 5137 } 5138 5139 static void 5140 db_print_file(struct file *fp, int header) 5141 { 5142 #define XPTRWIDTH ((int)howmany(sizeof(void *) * NBBY, 4)) 5143 struct proc *p; 5144 5145 if (header) 5146 db_printf("%*s %6s %*s %8s %4s %5s %6s %*s %5s %s\n", 5147 XPTRWIDTH, "File", "Type", XPTRWIDTH, "Data", "Flag", 5148 "GCFl", "Count", "MCount", XPTRWIDTH, "Vnode", "FPID", 5149 "FCmd"); 5150 p = file_to_first_proc(fp); 5151 db_printf("%*p %6s %*p %08x %04x %5d %6d %*p %5d %s\n", XPTRWIDTH, 5152 fp, file_type_to_name(fp->f_type), XPTRWIDTH, fp->f_data, 5153 fp->f_flag, 0, refcount_load(&fp->f_count), 0, XPTRWIDTH, fp->f_vnode, 5154 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 5155 5156 #undef XPTRWIDTH 5157 } 5158 5159 DB_SHOW_COMMAND(file, db_show_file) 5160 { 5161 struct file *fp; 5162 5163 if (!have_addr) { 5164 db_printf("usage: show file <addr>\n"); 5165 return; 5166 } 5167 fp = (struct file *)addr; 5168 db_print_file(fp, 1); 5169 } 5170 5171 DB_SHOW_COMMAND_FLAGS(files, db_show_files, DB_CMD_MEMSAFE) 5172 { 5173 struct filedesc *fdp; 5174 struct file *fp; 5175 struct proc *p; 5176 int header; 5177 int n; 5178 5179 header = 1; 5180 FOREACH_PROC_IN_SYSTEM(p) { 5181 if (p->p_state == PRS_NEW) 5182 continue; 5183 if ((fdp = p->p_fd) == NULL) 5184 continue; 5185 for (n = 0; n < fdp->fd_nfiles; ++n) { 5186 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 5187 continue; 5188 db_print_file(fp, header); 5189 header = 0; 5190 } 5191 } 5192 } 5193 #endif 5194 5195 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, 5196 CTLFLAG_RWTUN | CTLFLAG_NOFETCH, 5197 &maxfilesperproc, 0, "Maximum files allowed open per process"); 5198 5199 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, 5200 &maxfiles, 0, "Maximum number of files"); 5201 5202 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 5203 &openfiles, 0, "System-wide number of open files"); 5204 5205 /* ARGSUSED*/ 5206 static void 5207 filelistinit(void *dummy) 5208 { 5209 5210 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 5211 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 5212 filedesc0_zone = uma_zcreate("filedesc0", sizeof(struct filedesc0), 5213 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 5214 pwd_zone = uma_zcreate("PWD", sizeof(struct pwd), NULL, NULL, 5215 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_SMR); 5216 /* 5217 * XXXMJG this is a temporary hack due to boot ordering issues against 5218 * the vnode zone. 5219 */ 5220 vfs_smr = uma_zone_get_smr(pwd_zone); 5221 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 5222 } 5223 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 5224 5225 /*-------------------------------------------------------------------*/ 5226 5227 static int 5228 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 5229 int flags, struct thread *td) 5230 { 5231 5232 return (EBADF); 5233 } 5234 5235 static int 5236 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 5237 struct thread *td) 5238 { 5239 5240 return (EINVAL); 5241 } 5242 5243 static int 5244 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 5245 struct thread *td) 5246 { 5247 5248 return (EBADF); 5249 } 5250 5251 static int 5252 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 5253 struct thread *td) 5254 { 5255 5256 return (0); 5257 } 5258 5259 static int 5260 badfo_kqfilter(struct file *fp, struct knote *kn) 5261 { 5262 5263 return (EBADF); 5264 } 5265 5266 static int 5267 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred) 5268 { 5269 5270 return (EBADF); 5271 } 5272 5273 static int 5274 badfo_close(struct file *fp, struct thread *td) 5275 { 5276 5277 return (0); 5278 } 5279 5280 static int 5281 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 5282 struct thread *td) 5283 { 5284 5285 return (EBADF); 5286 } 5287 5288 static int 5289 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 5290 struct thread *td) 5291 { 5292 5293 return (EBADF); 5294 } 5295 5296 static int 5297 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 5298 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 5299 struct thread *td) 5300 { 5301 5302 return (EBADF); 5303 } 5304 5305 static int 5306 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp) 5307 { 5308 5309 return (0); 5310 } 5311 5312 const struct fileops badfileops = { 5313 .fo_read = badfo_readwrite, 5314 .fo_write = badfo_readwrite, 5315 .fo_truncate = badfo_truncate, 5316 .fo_ioctl = badfo_ioctl, 5317 .fo_poll = badfo_poll, 5318 .fo_kqfilter = badfo_kqfilter, 5319 .fo_stat = badfo_stat, 5320 .fo_close = badfo_close, 5321 .fo_chmod = badfo_chmod, 5322 .fo_chown = badfo_chown, 5323 .fo_sendfile = badfo_sendfile, 5324 .fo_fill_kinfo = badfo_fill_kinfo, 5325 }; 5326 5327 static int 5328 path_poll(struct file *fp, int events, struct ucred *active_cred, 5329 struct thread *td) 5330 { 5331 return (POLLNVAL); 5332 } 5333 5334 static int 5335 path_close(struct file *fp, struct thread *td) 5336 { 5337 MPASS(fp->f_type == DTYPE_VNODE); 5338 fp->f_ops = &badfileops; 5339 vrele(fp->f_vnode); 5340 return (0); 5341 } 5342 5343 const struct fileops path_fileops = { 5344 .fo_read = badfo_readwrite, 5345 .fo_write = badfo_readwrite, 5346 .fo_truncate = badfo_truncate, 5347 .fo_ioctl = badfo_ioctl, 5348 .fo_poll = path_poll, 5349 .fo_kqfilter = vn_kqfilter_opath, 5350 .fo_stat = vn_statfile, 5351 .fo_close = path_close, 5352 .fo_chmod = badfo_chmod, 5353 .fo_chown = badfo_chown, 5354 .fo_sendfile = badfo_sendfile, 5355 .fo_fill_kinfo = vn_fill_kinfo, 5356 .fo_cmp = vn_cmp, 5357 .fo_flags = DFLAG_PASSABLE, 5358 }; 5359 5360 int 5361 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred, 5362 int flags, struct thread *td) 5363 { 5364 5365 return (EOPNOTSUPP); 5366 } 5367 5368 int 5369 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 5370 struct thread *td) 5371 { 5372 5373 return (EINVAL); 5374 } 5375 5376 int 5377 invfo_ioctl(struct file *fp, u_long com, void *data, 5378 struct ucred *active_cred, struct thread *td) 5379 { 5380 5381 return (ENOTTY); 5382 } 5383 5384 int 5385 invfo_poll(struct file *fp, int events, struct ucred *active_cred, 5386 struct thread *td) 5387 { 5388 5389 return (poll_no_poll(events)); 5390 } 5391 5392 int 5393 invfo_kqfilter(struct file *fp, struct knote *kn) 5394 { 5395 5396 return (EINVAL); 5397 } 5398 5399 int 5400 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 5401 struct thread *td) 5402 { 5403 5404 return (EINVAL); 5405 } 5406 5407 int 5408 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 5409 struct thread *td) 5410 { 5411 5412 return (EINVAL); 5413 } 5414 5415 int 5416 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 5417 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 5418 struct thread *td) 5419 { 5420 5421 return (EINVAL); 5422 } 5423 5424 /*-------------------------------------------------------------------*/ 5425 5426 /* 5427 * File Descriptor pseudo-device driver (/dev/fd/). 5428 * 5429 * Opening minor device N dup()s the file (if any) connected to file 5430 * descriptor N belonging to the calling process. Note that this driver 5431 * consists of only the ``open()'' routine, because all subsequent 5432 * references to this file will be direct to the other driver. 5433 * 5434 * XXX: we could give this one a cloning event handler if necessary. 5435 */ 5436 5437 /* ARGSUSED */ 5438 static int 5439 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 5440 { 5441 5442 /* 5443 * XXX Kludge: set curthread->td_dupfd to contain the value of the 5444 * the file descriptor being sought for duplication. The error 5445 * return ensures that the vnode for this device will be released 5446 * by vn_open. Open will detect this special error and take the 5447 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 5448 * will simply report the error. 5449 */ 5450 td->td_dupfd = dev2unit(dev); 5451 return (ENODEV); 5452 } 5453 5454 static struct cdevsw fildesc_cdevsw = { 5455 .d_version = D_VERSION, 5456 .d_open = fdopen, 5457 .d_name = "FD", 5458 }; 5459 5460 static void 5461 fildesc_drvinit(void *unused) 5462 { 5463 struct cdev *dev; 5464 5465 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 5466 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 5467 make_dev_alias(dev, "stdin"); 5468 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 5469 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 5470 make_dev_alias(dev, "stdout"); 5471 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 5472 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 5473 make_dev_alias(dev, "stderr"); 5474 } 5475 5476 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 5477