1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_capsicum.h" 41 #include "opt_compat.h" 42 #include "opt_ddb.h" 43 #include "opt_ktrace.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 48 #include <sys/capsicum.h> 49 #include <sys/conf.h> 50 #include <sys/fcntl.h> 51 #include <sys/file.h> 52 #include <sys/filedesc.h> 53 #include <sys/filio.h> 54 #include <sys/jail.h> 55 #include <sys/kernel.h> 56 #include <sys/limits.h> 57 #include <sys/lock.h> 58 #include <sys/malloc.h> 59 #include <sys/mount.h> 60 #include <sys/mutex.h> 61 #include <sys/namei.h> 62 #include <sys/selinfo.h> 63 #include <sys/priv.h> 64 #include <sys/proc.h> 65 #include <sys/protosw.h> 66 #include <sys/racct.h> 67 #include <sys/resourcevar.h> 68 #include <sys/sbuf.h> 69 #include <sys/signalvar.h> 70 #include <sys/kdb.h> 71 #include <sys/stat.h> 72 #include <sys/sx.h> 73 #include <sys/syscallsubr.h> 74 #include <sys/sysctl.h> 75 #include <sys/sysproto.h> 76 #include <sys/unistd.h> 77 #include <sys/user.h> 78 #include <sys/vnode.h> 79 #ifdef KTRACE 80 #include <sys/ktrace.h> 81 #endif 82 83 #include <net/vnet.h> 84 85 #include <security/audit/audit.h> 86 87 #include <vm/uma.h> 88 #include <vm/vm.h> 89 90 #include <ddb/ddb.h> 91 92 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 93 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 94 "file desc to leader structures"); 95 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 96 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 97 98 MALLOC_DECLARE(M_FADVISE); 99 100 static __read_mostly uma_zone_t file_zone; 101 static __read_mostly uma_zone_t filedesc0_zone; 102 103 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 104 struct thread *td, int holdleaders); 105 static int fd_first_free(struct filedesc *fdp, int low, int size); 106 static int fd_last_used(struct filedesc *fdp, 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 getmaxfd(struct thread *td); 112 113 /* 114 * Each process has: 115 * 116 * - An array of open file descriptors (fd_ofiles) 117 * - An array of file flags (fd_ofileflags) 118 * - A bitmap recording which descriptors are in use (fd_map) 119 * 120 * A process starts out with NDFILE descriptors. The value of NDFILE has 121 * been selected based the historical limit of 20 open files, and an 122 * assumption that the majority of processes, especially short-lived 123 * processes like shells, will never need more. 124 * 125 * If this initial allocation is exhausted, a larger descriptor table and 126 * map are allocated dynamically, and the pointers in the process's struct 127 * filedesc are updated to point to those. This is repeated every time 128 * the process runs out of file descriptors (provided it hasn't hit its 129 * resource limit). 130 * 131 * Since threads may hold references to individual descriptor table 132 * entries, the tables are never freed. Instead, they are placed on a 133 * linked list and freed only when the struct filedesc is released. 134 */ 135 #define NDFILE 20 136 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 137 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 138 #define NDSLOT(x) ((x) / NDENTRIES) 139 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 140 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 141 142 /* 143 * SLIST entry used to keep track of ofiles which must be reclaimed when 144 * the process exits. 145 */ 146 struct freetable { 147 struct fdescenttbl *ft_table; 148 SLIST_ENTRY(freetable) ft_next; 149 }; 150 151 /* 152 * Initial allocation: a filedesc structure + the head of SLIST used to 153 * keep track of old ofiles + enough space for NDFILE descriptors. 154 */ 155 156 struct fdescenttbl0 { 157 int fdt_nfiles; 158 struct filedescent fdt_ofiles[NDFILE]; 159 }; 160 161 struct filedesc0 { 162 struct filedesc fd_fd; 163 SLIST_HEAD(, freetable) fd_free; 164 struct fdescenttbl0 fd_dfiles; 165 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 166 }; 167 168 /* 169 * Descriptor management. 170 */ 171 volatile int __exclusive_cache_line openfiles; /* actual number of open files */ 172 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 173 void __read_mostly (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 174 175 /* 176 * If low >= size, just return low. Otherwise find the first zero bit in the 177 * given bitmap, starting at low and not exceeding size - 1. Return size if 178 * not found. 179 */ 180 static int 181 fd_first_free(struct filedesc *fdp, int low, int size) 182 { 183 NDSLOTTYPE *map = fdp->fd_map; 184 NDSLOTTYPE mask; 185 int off, maxoff; 186 187 if (low >= size) 188 return (low); 189 190 off = NDSLOT(low); 191 if (low % NDENTRIES) { 192 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 193 if ((mask &= ~map[off]) != 0UL) 194 return (off * NDENTRIES + ffsl(mask) - 1); 195 ++off; 196 } 197 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 198 if (map[off] != ~0UL) 199 return (off * NDENTRIES + ffsl(~map[off]) - 1); 200 return (size); 201 } 202 203 /* 204 * Find the highest non-zero bit in the given bitmap, starting at 0 and 205 * not exceeding size - 1. Return -1 if not found. 206 */ 207 static int 208 fd_last_used(struct filedesc *fdp, int size) 209 { 210 NDSLOTTYPE *map = fdp->fd_map; 211 NDSLOTTYPE mask; 212 int off, minoff; 213 214 off = NDSLOT(size); 215 if (size % NDENTRIES) { 216 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 217 if ((mask &= map[off]) != 0) 218 return (off * NDENTRIES + flsl(mask) - 1); 219 --off; 220 } 221 for (minoff = NDSLOT(0); off >= minoff; --off) 222 if (map[off] != 0) 223 return (off * NDENTRIES + flsl(map[off]) - 1); 224 return (-1); 225 } 226 227 static int 228 fdisused(struct filedesc *fdp, int fd) 229 { 230 231 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 232 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 233 234 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 235 } 236 237 /* 238 * Mark a file descriptor as used. 239 */ 240 static void 241 fdused_init(struct filedesc *fdp, int fd) 242 { 243 244 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 245 246 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 247 } 248 249 static void 250 fdused(struct filedesc *fdp, int fd) 251 { 252 253 FILEDESC_XLOCK_ASSERT(fdp); 254 255 fdused_init(fdp, fd); 256 if (fd > fdp->fd_lastfile) 257 fdp->fd_lastfile = fd; 258 if (fd == fdp->fd_freefile) 259 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 260 } 261 262 /* 263 * Mark a file descriptor as unused. 264 */ 265 static void 266 fdunused(struct filedesc *fdp, int fd) 267 { 268 269 FILEDESC_XLOCK_ASSERT(fdp); 270 271 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 272 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 273 ("fd=%d is still in use", fd)); 274 275 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 276 if (fd < fdp->fd_freefile) 277 fdp->fd_freefile = fd; 278 if (fd == fdp->fd_lastfile) 279 fdp->fd_lastfile = fd_last_used(fdp, fd); 280 } 281 282 /* 283 * Free a file descriptor. 284 * 285 * Avoid some work if fdp is about to be destroyed. 286 */ 287 static inline void 288 fdefree_last(struct filedescent *fde) 289 { 290 291 filecaps_free(&fde->fde_caps); 292 } 293 294 static inline void 295 fdfree(struct filedesc *fdp, int fd) 296 { 297 struct filedescent *fde; 298 299 fde = &fdp->fd_ofiles[fd]; 300 #ifdef CAPABILITIES 301 seq_write_begin(&fde->fde_seq); 302 #endif 303 fdefree_last(fde); 304 fde->fde_file = NULL; 305 fdunused(fdp, fd); 306 #ifdef CAPABILITIES 307 seq_write_end(&fde->fde_seq); 308 #endif 309 } 310 311 void 312 pwd_ensure_dirs(void) 313 { 314 struct filedesc *fdp; 315 316 fdp = curproc->p_fd; 317 FILEDESC_XLOCK(fdp); 318 if (fdp->fd_cdir == NULL) { 319 fdp->fd_cdir = rootvnode; 320 vrefact(rootvnode); 321 } 322 if (fdp->fd_rdir == NULL) { 323 fdp->fd_rdir = rootvnode; 324 vrefact(rootvnode); 325 } 326 FILEDESC_XUNLOCK(fdp); 327 } 328 329 /* 330 * System calls on descriptors. 331 */ 332 #ifndef _SYS_SYSPROTO_H_ 333 struct getdtablesize_args { 334 int dummy; 335 }; 336 #endif 337 /* ARGSUSED */ 338 int 339 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 340 { 341 #ifdef RACCT 342 uint64_t lim; 343 #endif 344 345 td->td_retval[0] = 346 min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc); 347 #ifdef RACCT 348 PROC_LOCK(td->td_proc); 349 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 350 PROC_UNLOCK(td->td_proc); 351 if (lim < td->td_retval[0]) 352 td->td_retval[0] = lim; 353 #endif 354 return (0); 355 } 356 357 /* 358 * Duplicate a file descriptor to a particular value. 359 * 360 * Note: keep in mind that a potential race condition exists when closing 361 * descriptors from a shared descriptor table (via rfork). 362 */ 363 #ifndef _SYS_SYSPROTO_H_ 364 struct dup2_args { 365 u_int from; 366 u_int to; 367 }; 368 #endif 369 /* ARGSUSED */ 370 int 371 sys_dup2(struct thread *td, struct dup2_args *uap) 372 { 373 374 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to)); 375 } 376 377 /* 378 * Duplicate a file descriptor. 379 */ 380 #ifndef _SYS_SYSPROTO_H_ 381 struct dup_args { 382 u_int fd; 383 }; 384 #endif 385 /* ARGSUSED */ 386 int 387 sys_dup(struct thread *td, struct dup_args *uap) 388 { 389 390 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0)); 391 } 392 393 /* 394 * The file control system call. 395 */ 396 #ifndef _SYS_SYSPROTO_H_ 397 struct fcntl_args { 398 int fd; 399 int cmd; 400 long arg; 401 }; 402 #endif 403 /* ARGSUSED */ 404 int 405 sys_fcntl(struct thread *td, struct fcntl_args *uap) 406 { 407 408 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg)); 409 } 410 411 int 412 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg) 413 { 414 struct flock fl; 415 struct __oflock ofl; 416 intptr_t arg1; 417 int error, newcmd; 418 419 error = 0; 420 newcmd = cmd; 421 switch (cmd) { 422 case F_OGETLK: 423 case F_OSETLK: 424 case F_OSETLKW: 425 /* 426 * Convert old flock structure to new. 427 */ 428 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl)); 429 fl.l_start = ofl.l_start; 430 fl.l_len = ofl.l_len; 431 fl.l_pid = ofl.l_pid; 432 fl.l_type = ofl.l_type; 433 fl.l_whence = ofl.l_whence; 434 fl.l_sysid = 0; 435 436 switch (cmd) { 437 case F_OGETLK: 438 newcmd = F_GETLK; 439 break; 440 case F_OSETLK: 441 newcmd = F_SETLK; 442 break; 443 case F_OSETLKW: 444 newcmd = F_SETLKW; 445 break; 446 } 447 arg1 = (intptr_t)&fl; 448 break; 449 case F_GETLK: 450 case F_SETLK: 451 case F_SETLKW: 452 case F_SETLK_REMOTE: 453 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl)); 454 arg1 = (intptr_t)&fl; 455 break; 456 default: 457 arg1 = arg; 458 break; 459 } 460 if (error) 461 return (error); 462 error = kern_fcntl(td, fd, newcmd, arg1); 463 if (error) 464 return (error); 465 if (cmd == F_OGETLK) { 466 ofl.l_start = fl.l_start; 467 ofl.l_len = fl.l_len; 468 ofl.l_pid = fl.l_pid; 469 ofl.l_type = fl.l_type; 470 ofl.l_whence = fl.l_whence; 471 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl)); 472 } else if (cmd == F_GETLK) { 473 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl)); 474 } 475 return (error); 476 } 477 478 int 479 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 480 { 481 struct filedesc *fdp; 482 struct flock *flp; 483 struct file *fp, *fp2; 484 struct filedescent *fde; 485 struct proc *p; 486 struct vnode *vp; 487 cap_rights_t rights; 488 int error, flg, tmp; 489 uint64_t bsize; 490 off_t foffset; 491 492 error = 0; 493 flg = F_POSIX; 494 p = td->td_proc; 495 fdp = p->p_fd; 496 497 AUDIT_ARG_FD(cmd); 498 AUDIT_ARG_CMD(cmd); 499 switch (cmd) { 500 case F_DUPFD: 501 tmp = arg; 502 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp); 503 break; 504 505 case F_DUPFD_CLOEXEC: 506 tmp = arg; 507 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp); 508 break; 509 510 case F_DUP2FD: 511 tmp = arg; 512 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp); 513 break; 514 515 case F_DUP2FD_CLOEXEC: 516 tmp = arg; 517 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp); 518 break; 519 520 case F_GETFD: 521 error = EBADF; 522 FILEDESC_SLOCK(fdp); 523 fde = fdeget_locked(fdp, fd); 524 if (fde != NULL) { 525 td->td_retval[0] = 526 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 527 error = 0; 528 } 529 FILEDESC_SUNLOCK(fdp); 530 break; 531 532 case F_SETFD: 533 error = EBADF; 534 FILEDESC_XLOCK(fdp); 535 fde = fdeget_locked(fdp, fd); 536 if (fde != NULL) { 537 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 538 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 539 error = 0; 540 } 541 FILEDESC_XUNLOCK(fdp); 542 break; 543 544 case F_GETFL: 545 error = fget_fcntl(td, fd, 546 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp); 547 if (error != 0) 548 break; 549 td->td_retval[0] = OFLAGS(fp->f_flag); 550 fdrop(fp, td); 551 break; 552 553 case F_SETFL: 554 error = fget_fcntl(td, fd, 555 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp); 556 if (error != 0) 557 break; 558 do { 559 tmp = flg = fp->f_flag; 560 tmp &= ~FCNTLFLAGS; 561 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 562 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 563 tmp = fp->f_flag & FNONBLOCK; 564 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 565 if (error != 0) { 566 fdrop(fp, td); 567 break; 568 } 569 tmp = fp->f_flag & FASYNC; 570 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 571 if (error == 0) { 572 fdrop(fp, td); 573 break; 574 } 575 atomic_clear_int(&fp->f_flag, FNONBLOCK); 576 tmp = 0; 577 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 578 fdrop(fp, td); 579 break; 580 581 case F_GETOWN: 582 error = fget_fcntl(td, fd, 583 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp); 584 if (error != 0) 585 break; 586 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 587 if (error == 0) 588 td->td_retval[0] = tmp; 589 fdrop(fp, td); 590 break; 591 592 case F_SETOWN: 593 error = fget_fcntl(td, fd, 594 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp); 595 if (error != 0) 596 break; 597 tmp = arg; 598 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 599 fdrop(fp, td); 600 break; 601 602 case F_SETLK_REMOTE: 603 error = priv_check(td, PRIV_NFS_LOCKD); 604 if (error) 605 return (error); 606 flg = F_REMOTE; 607 goto do_setlk; 608 609 case F_SETLKW: 610 flg |= F_WAIT; 611 /* FALLTHROUGH F_SETLK */ 612 613 case F_SETLK: 614 do_setlk: 615 cap_rights_init(&rights, CAP_FLOCK); 616 error = fget_unlocked(fdp, fd, &rights, &fp, NULL); 617 if (error != 0) 618 break; 619 if (fp->f_type != DTYPE_VNODE) { 620 error = EBADF; 621 fdrop(fp, td); 622 break; 623 } 624 625 flp = (struct flock *)arg; 626 if (flp->l_whence == SEEK_CUR) { 627 foffset = foffset_get(fp); 628 if (foffset < 0 || 629 (flp->l_start > 0 && 630 foffset > OFF_MAX - flp->l_start)) { 631 error = EOVERFLOW; 632 fdrop(fp, td); 633 break; 634 } 635 flp->l_start += foffset; 636 } 637 638 vp = fp->f_vnode; 639 switch (flp->l_type) { 640 case F_RDLCK: 641 if ((fp->f_flag & FREAD) == 0) { 642 error = EBADF; 643 break; 644 } 645 PROC_LOCK(p->p_leader); 646 p->p_leader->p_flag |= P_ADVLOCK; 647 PROC_UNLOCK(p->p_leader); 648 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 649 flp, flg); 650 break; 651 case F_WRLCK: 652 if ((fp->f_flag & FWRITE) == 0) { 653 error = EBADF; 654 break; 655 } 656 PROC_LOCK(p->p_leader); 657 p->p_leader->p_flag |= P_ADVLOCK; 658 PROC_UNLOCK(p->p_leader); 659 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 660 flp, flg); 661 break; 662 case F_UNLCK: 663 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 664 flp, flg); 665 break; 666 case F_UNLCKSYS: 667 /* 668 * Temporary api for testing remote lock 669 * infrastructure. 670 */ 671 if (flg != F_REMOTE) { 672 error = EINVAL; 673 break; 674 } 675 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 676 F_UNLCKSYS, flp, flg); 677 break; 678 default: 679 error = EINVAL; 680 break; 681 } 682 if (error != 0 || flp->l_type == F_UNLCK || 683 flp->l_type == F_UNLCKSYS) { 684 fdrop(fp, td); 685 break; 686 } 687 688 /* 689 * Check for a race with close. 690 * 691 * The vnode is now advisory locked (or unlocked, but this case 692 * is not really important) as the caller requested. 693 * We had to drop the filedesc lock, so we need to recheck if 694 * the descriptor is still valid, because if it was closed 695 * in the meantime we need to remove advisory lock from the 696 * vnode - close on any descriptor leading to an advisory 697 * locked vnode, removes that lock. 698 * We will return 0 on purpose in that case, as the result of 699 * successful advisory lock might have been externally visible 700 * already. This is fine - effectively we pretend to the caller 701 * that the closing thread was a bit slower and that the 702 * advisory lock succeeded before the close. 703 */ 704 error = fget_unlocked(fdp, fd, &rights, &fp2, NULL); 705 if (error != 0) { 706 fdrop(fp, td); 707 break; 708 } 709 if (fp != fp2) { 710 flp->l_whence = SEEK_SET; 711 flp->l_start = 0; 712 flp->l_len = 0; 713 flp->l_type = F_UNLCK; 714 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 715 F_UNLCK, flp, F_POSIX); 716 } 717 fdrop(fp, td); 718 fdrop(fp2, td); 719 break; 720 721 case F_GETLK: 722 error = fget_unlocked(fdp, fd, 723 cap_rights_init(&rights, CAP_FLOCK), &fp, NULL); 724 if (error != 0) 725 break; 726 if (fp->f_type != DTYPE_VNODE) { 727 error = EBADF; 728 fdrop(fp, td); 729 break; 730 } 731 flp = (struct flock *)arg; 732 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 733 flp->l_type != F_UNLCK) { 734 error = EINVAL; 735 fdrop(fp, td); 736 break; 737 } 738 if (flp->l_whence == SEEK_CUR) { 739 foffset = foffset_get(fp); 740 if ((flp->l_start > 0 && 741 foffset > OFF_MAX - flp->l_start) || 742 (flp->l_start < 0 && 743 foffset < OFF_MIN - flp->l_start)) { 744 error = EOVERFLOW; 745 fdrop(fp, td); 746 break; 747 } 748 flp->l_start += foffset; 749 } 750 vp = fp->f_vnode; 751 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 752 F_POSIX); 753 fdrop(fp, td); 754 break; 755 756 case F_RDAHEAD: 757 arg = arg ? 128 * 1024: 0; 758 /* FALLTHROUGH */ 759 case F_READAHEAD: 760 error = fget_unlocked(fdp, fd, 761 cap_rights_init(&rights), &fp, NULL); 762 if (error != 0) 763 break; 764 if (fp->f_type != DTYPE_VNODE) { 765 fdrop(fp, td); 766 error = EBADF; 767 break; 768 } 769 vp = fp->f_vnode; 770 /* 771 * Exclusive lock synchronizes against f_seqcount reads and 772 * writes in sequential_heuristic(). 773 */ 774 error = vn_lock(vp, LK_EXCLUSIVE); 775 if (error != 0) { 776 fdrop(fp, td); 777 break; 778 } 779 if (arg >= 0) { 780 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 781 fp->f_seqcount = (arg + bsize - 1) / bsize; 782 atomic_set_int(&fp->f_flag, FRDAHEAD); 783 } else { 784 atomic_clear_int(&fp->f_flag, FRDAHEAD); 785 } 786 VOP_UNLOCK(vp, 0); 787 fdrop(fp, td); 788 break; 789 790 default: 791 error = EINVAL; 792 break; 793 } 794 return (error); 795 } 796 797 static int 798 getmaxfd(struct thread *td) 799 { 800 801 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc)); 802 } 803 804 /* 805 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 806 */ 807 int 808 kern_dup(struct thread *td, u_int mode, int flags, int old, int new) 809 { 810 struct filedesc *fdp; 811 struct filedescent *oldfde, *newfde; 812 struct proc *p; 813 struct file *delfp; 814 int error, maxfd; 815 816 p = td->td_proc; 817 fdp = p->p_fd; 818 819 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0); 820 MPASS(mode < FDDUP_LASTMODE); 821 822 AUDIT_ARG_FD(old); 823 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */ 824 825 /* 826 * Verify we have a valid descriptor to dup from and possibly to 827 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 828 * return EINVAL when the new descriptor is out of bounds. 829 */ 830 if (old < 0) 831 return (EBADF); 832 if (new < 0) 833 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 834 maxfd = getmaxfd(td); 835 if (new >= maxfd) 836 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 837 838 error = EBADF; 839 FILEDESC_XLOCK(fdp); 840 if (fget_locked(fdp, old) == NULL) 841 goto unlock; 842 if ((mode == FDDUP_FIXED || mode == FDDUP_MUSTREPLACE) && old == new) { 843 td->td_retval[0] = new; 844 if (flags & FDDUP_FLAG_CLOEXEC) 845 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 846 error = 0; 847 goto unlock; 848 } 849 850 /* 851 * If the caller specified a file descriptor, make sure the file 852 * table is large enough to hold it, and grab it. Otherwise, just 853 * allocate a new descriptor the usual way. 854 */ 855 switch (mode) { 856 case FDDUP_NORMAL: 857 case FDDUP_FCNTL: 858 if ((error = fdalloc(td, new, &new)) != 0) 859 goto unlock; 860 break; 861 case FDDUP_MUSTREPLACE: 862 /* Target file descriptor must exist. */ 863 if (fget_locked(fdp, new) == NULL) 864 goto unlock; 865 break; 866 case FDDUP_FIXED: 867 if (new >= fdp->fd_nfiles) { 868 /* 869 * The resource limits are here instead of e.g. 870 * fdalloc(), because the file descriptor table may be 871 * shared between processes, so we can't really use 872 * racct_add()/racct_sub(). Instead of counting the 873 * number of actually allocated descriptors, just put 874 * the limit on the size of the file descriptor table. 875 */ 876 #ifdef RACCT 877 if (racct_enable) { 878 PROC_LOCK(p); 879 error = racct_set(p, RACCT_NOFILE, new + 1); 880 PROC_UNLOCK(p); 881 if (error != 0) { 882 error = EMFILE; 883 goto unlock; 884 } 885 } 886 #endif 887 fdgrowtable_exp(fdp, new + 1); 888 } 889 if (!fdisused(fdp, new)) 890 fdused(fdp, new); 891 break; 892 default: 893 KASSERT(0, ("%s unsupported mode %d", __func__, mode)); 894 } 895 896 KASSERT(old != new, ("new fd is same as old")); 897 898 oldfde = &fdp->fd_ofiles[old]; 899 fhold(oldfde->fde_file); 900 newfde = &fdp->fd_ofiles[new]; 901 delfp = newfde->fde_file; 902 903 /* 904 * Duplicate the source descriptor. 905 */ 906 #ifdef CAPABILITIES 907 seq_write_begin(&newfde->fde_seq); 908 #endif 909 filecaps_free(&newfde->fde_caps); 910 memcpy(newfde, oldfde, fde_change_size); 911 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps, true); 912 if ((flags & FDDUP_FLAG_CLOEXEC) != 0) 913 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 914 else 915 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 916 #ifdef CAPABILITIES 917 seq_write_end(&newfde->fde_seq); 918 #endif 919 td->td_retval[0] = new; 920 921 error = 0; 922 923 if (delfp != NULL) { 924 (void) closefp(fdp, new, delfp, td, 1); 925 FILEDESC_UNLOCK_ASSERT(fdp); 926 } else { 927 unlock: 928 FILEDESC_XUNLOCK(fdp); 929 } 930 931 return (error); 932 } 933 934 /* 935 * If sigio is on the list associated with a process or process group, 936 * disable signalling from the device, remove sigio from the list and 937 * free sigio. 938 */ 939 void 940 funsetown(struct sigio **sigiop) 941 { 942 struct sigio *sigio; 943 944 if (*sigiop == NULL) 945 return; 946 SIGIO_LOCK(); 947 sigio = *sigiop; 948 if (sigio == NULL) { 949 SIGIO_UNLOCK(); 950 return; 951 } 952 *(sigio->sio_myref) = NULL; 953 if ((sigio)->sio_pgid < 0) { 954 struct pgrp *pg = (sigio)->sio_pgrp; 955 PGRP_LOCK(pg); 956 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 957 sigio, sio_pgsigio); 958 PGRP_UNLOCK(pg); 959 } else { 960 struct proc *p = (sigio)->sio_proc; 961 PROC_LOCK(p); 962 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 963 sigio, sio_pgsigio); 964 PROC_UNLOCK(p); 965 } 966 SIGIO_UNLOCK(); 967 crfree(sigio->sio_ucred); 968 free(sigio, M_SIGIO); 969 } 970 971 /* 972 * Free a list of sigio structures. 973 * We only need to lock the SIGIO_LOCK because we have made ourselves 974 * inaccessible to callers of fsetown and therefore do not need to lock 975 * the proc or pgrp struct for the list manipulation. 976 */ 977 void 978 funsetownlst(struct sigiolst *sigiolst) 979 { 980 struct proc *p; 981 struct pgrp *pg; 982 struct sigio *sigio; 983 984 sigio = SLIST_FIRST(sigiolst); 985 if (sigio == NULL) 986 return; 987 p = NULL; 988 pg = NULL; 989 990 /* 991 * Every entry of the list should belong 992 * to a single proc or pgrp. 993 */ 994 if (sigio->sio_pgid < 0) { 995 pg = sigio->sio_pgrp; 996 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 997 } else /* if (sigio->sio_pgid > 0) */ { 998 p = sigio->sio_proc; 999 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 1000 } 1001 1002 SIGIO_LOCK(); 1003 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 1004 *(sigio->sio_myref) = NULL; 1005 if (pg != NULL) { 1006 KASSERT(sigio->sio_pgid < 0, 1007 ("Proc sigio in pgrp sigio list")); 1008 KASSERT(sigio->sio_pgrp == pg, 1009 ("Bogus pgrp in sigio list")); 1010 PGRP_LOCK(pg); 1011 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 1012 sio_pgsigio); 1013 PGRP_UNLOCK(pg); 1014 } else /* if (p != NULL) */ { 1015 KASSERT(sigio->sio_pgid > 0, 1016 ("Pgrp sigio in proc sigio list")); 1017 KASSERT(sigio->sio_proc == p, 1018 ("Bogus proc in sigio list")); 1019 PROC_LOCK(p); 1020 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 1021 sio_pgsigio); 1022 PROC_UNLOCK(p); 1023 } 1024 SIGIO_UNLOCK(); 1025 crfree(sigio->sio_ucred); 1026 free(sigio, M_SIGIO); 1027 SIGIO_LOCK(); 1028 } 1029 SIGIO_UNLOCK(); 1030 } 1031 1032 /* 1033 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1034 * 1035 * After permission checking, add a sigio structure to the sigio list for 1036 * the process or process group. 1037 */ 1038 int 1039 fsetown(pid_t pgid, struct sigio **sigiop) 1040 { 1041 struct proc *proc; 1042 struct pgrp *pgrp; 1043 struct sigio *sigio; 1044 int ret; 1045 1046 if (pgid == 0) { 1047 funsetown(sigiop); 1048 return (0); 1049 } 1050 1051 ret = 0; 1052 1053 /* Allocate and fill in the new sigio out of locks. */ 1054 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1055 sigio->sio_pgid = pgid; 1056 sigio->sio_ucred = crhold(curthread->td_ucred); 1057 sigio->sio_myref = sigiop; 1058 1059 sx_slock(&proctree_lock); 1060 if (pgid > 0) { 1061 proc = pfind(pgid); 1062 if (proc == NULL) { 1063 ret = ESRCH; 1064 goto fail; 1065 } 1066 1067 /* 1068 * Policy - Don't allow a process to FSETOWN a process 1069 * in another session. 1070 * 1071 * Remove this test to allow maximum flexibility or 1072 * restrict FSETOWN to the current process or process 1073 * group for maximum safety. 1074 */ 1075 PROC_UNLOCK(proc); 1076 if (proc->p_session != curthread->td_proc->p_session) { 1077 ret = EPERM; 1078 goto fail; 1079 } 1080 1081 pgrp = NULL; 1082 } else /* if (pgid < 0) */ { 1083 pgrp = pgfind(-pgid); 1084 if (pgrp == NULL) { 1085 ret = ESRCH; 1086 goto fail; 1087 } 1088 PGRP_UNLOCK(pgrp); 1089 1090 /* 1091 * Policy - Don't allow a process to FSETOWN a process 1092 * in another session. 1093 * 1094 * Remove this test to allow maximum flexibility or 1095 * restrict FSETOWN to the current process or process 1096 * group for maximum safety. 1097 */ 1098 if (pgrp->pg_session != curthread->td_proc->p_session) { 1099 ret = EPERM; 1100 goto fail; 1101 } 1102 1103 proc = NULL; 1104 } 1105 funsetown(sigiop); 1106 if (pgid > 0) { 1107 PROC_LOCK(proc); 1108 /* 1109 * Since funsetownlst() is called without the proctree 1110 * locked, we need to check for P_WEXIT. 1111 * XXX: is ESRCH correct? 1112 */ 1113 if ((proc->p_flag & P_WEXIT) != 0) { 1114 PROC_UNLOCK(proc); 1115 ret = ESRCH; 1116 goto fail; 1117 } 1118 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1119 sigio->sio_proc = proc; 1120 PROC_UNLOCK(proc); 1121 } else { 1122 PGRP_LOCK(pgrp); 1123 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1124 sigio->sio_pgrp = pgrp; 1125 PGRP_UNLOCK(pgrp); 1126 } 1127 sx_sunlock(&proctree_lock); 1128 SIGIO_LOCK(); 1129 *sigiop = sigio; 1130 SIGIO_UNLOCK(); 1131 return (0); 1132 1133 fail: 1134 sx_sunlock(&proctree_lock); 1135 crfree(sigio->sio_ucred); 1136 free(sigio, M_SIGIO); 1137 return (ret); 1138 } 1139 1140 /* 1141 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1142 */ 1143 pid_t 1144 fgetown(sigiop) 1145 struct sigio **sigiop; 1146 { 1147 pid_t pgid; 1148 1149 SIGIO_LOCK(); 1150 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1151 SIGIO_UNLOCK(); 1152 return (pgid); 1153 } 1154 1155 /* 1156 * Function drops the filedesc lock on return. 1157 */ 1158 static int 1159 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1160 int holdleaders) 1161 { 1162 int error; 1163 1164 FILEDESC_XLOCK_ASSERT(fdp); 1165 1166 if (holdleaders) { 1167 if (td->td_proc->p_fdtol != NULL) { 1168 /* 1169 * Ask fdfree() to sleep to ensure that all relevant 1170 * process leaders can be traversed in closef(). 1171 */ 1172 fdp->fd_holdleaderscount++; 1173 } else { 1174 holdleaders = 0; 1175 } 1176 } 1177 1178 /* 1179 * We now hold the fp reference that used to be owned by the 1180 * descriptor array. We have to unlock the FILEDESC *AFTER* 1181 * knote_fdclose to prevent a race of the fd getting opened, a knote 1182 * added, and deleteing a knote for the new fd. 1183 */ 1184 knote_fdclose(td, fd); 1185 1186 /* 1187 * We need to notify mqueue if the object is of type mqueue. 1188 */ 1189 if (fp->f_type == DTYPE_MQUEUE) 1190 mq_fdclose(td, fd, fp); 1191 FILEDESC_XUNLOCK(fdp); 1192 1193 error = closef(fp, td); 1194 if (holdleaders) { 1195 FILEDESC_XLOCK(fdp); 1196 fdp->fd_holdleaderscount--; 1197 if (fdp->fd_holdleaderscount == 0 && 1198 fdp->fd_holdleaderswakeup != 0) { 1199 fdp->fd_holdleaderswakeup = 0; 1200 wakeup(&fdp->fd_holdleaderscount); 1201 } 1202 FILEDESC_XUNLOCK(fdp); 1203 } 1204 return (error); 1205 } 1206 1207 /* 1208 * Close a file descriptor. 1209 */ 1210 #ifndef _SYS_SYSPROTO_H_ 1211 struct close_args { 1212 int fd; 1213 }; 1214 #endif 1215 /* ARGSUSED */ 1216 int 1217 sys_close(struct thread *td, struct close_args *uap) 1218 { 1219 1220 return (kern_close(td, uap->fd)); 1221 } 1222 1223 int 1224 kern_close(struct thread *td, int fd) 1225 { 1226 struct filedesc *fdp; 1227 struct file *fp; 1228 1229 fdp = td->td_proc->p_fd; 1230 1231 AUDIT_SYSCLOSE(td, fd); 1232 1233 FILEDESC_XLOCK(fdp); 1234 if ((fp = fget_locked(fdp, fd)) == NULL) { 1235 FILEDESC_XUNLOCK(fdp); 1236 return (EBADF); 1237 } 1238 fdfree(fdp, fd); 1239 1240 /* closefp() drops the FILEDESC lock for us. */ 1241 return (closefp(fdp, fd, fp, td, 1)); 1242 } 1243 1244 /* 1245 * Close open file descriptors. 1246 */ 1247 #ifndef _SYS_SYSPROTO_H_ 1248 struct closefrom_args { 1249 int lowfd; 1250 }; 1251 #endif 1252 /* ARGSUSED */ 1253 int 1254 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1255 { 1256 struct filedesc *fdp; 1257 int fd; 1258 1259 fdp = td->td_proc->p_fd; 1260 AUDIT_ARG_FD(uap->lowfd); 1261 1262 /* 1263 * Treat negative starting file descriptor values identical to 1264 * closefrom(0) which closes all files. 1265 */ 1266 if (uap->lowfd < 0) 1267 uap->lowfd = 0; 1268 FILEDESC_SLOCK(fdp); 1269 for (fd = uap->lowfd; fd <= fdp->fd_lastfile; fd++) { 1270 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1271 FILEDESC_SUNLOCK(fdp); 1272 (void)kern_close(td, fd); 1273 FILEDESC_SLOCK(fdp); 1274 } 1275 } 1276 FILEDESC_SUNLOCK(fdp); 1277 return (0); 1278 } 1279 1280 #if defined(COMPAT_43) 1281 /* 1282 * Return status information about a file descriptor. 1283 */ 1284 #ifndef _SYS_SYSPROTO_H_ 1285 struct ofstat_args { 1286 int fd; 1287 struct ostat *sb; 1288 }; 1289 #endif 1290 /* ARGSUSED */ 1291 int 1292 ofstat(struct thread *td, struct ofstat_args *uap) 1293 { 1294 struct ostat oub; 1295 struct stat ub; 1296 int error; 1297 1298 error = kern_fstat(td, uap->fd, &ub); 1299 if (error == 0) { 1300 cvtstat(&ub, &oub); 1301 error = copyout(&oub, uap->sb, sizeof(oub)); 1302 } 1303 return (error); 1304 } 1305 #endif /* COMPAT_43 */ 1306 1307 /* 1308 * Return status information about a file descriptor. 1309 */ 1310 #ifndef _SYS_SYSPROTO_H_ 1311 struct fstat_args { 1312 int fd; 1313 struct stat *sb; 1314 }; 1315 #endif 1316 /* ARGSUSED */ 1317 int 1318 sys_fstat(struct thread *td, struct fstat_args *uap) 1319 { 1320 struct stat ub; 1321 int error; 1322 1323 error = kern_fstat(td, uap->fd, &ub); 1324 if (error == 0) 1325 error = copyout(&ub, uap->sb, sizeof(ub)); 1326 return (error); 1327 } 1328 1329 int 1330 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1331 { 1332 struct file *fp; 1333 cap_rights_t rights; 1334 int error; 1335 1336 AUDIT_ARG_FD(fd); 1337 1338 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1339 if (error != 0) 1340 return (error); 1341 1342 AUDIT_ARG_FILE(td->td_proc, fp); 1343 1344 error = fo_stat(fp, sbp, td->td_ucred, td); 1345 fdrop(fp, td); 1346 #ifdef KTRACE 1347 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1348 ktrstat(sbp); 1349 #endif 1350 return (error); 1351 } 1352 1353 /* 1354 * Return status information about a file descriptor. 1355 */ 1356 #ifndef _SYS_SYSPROTO_H_ 1357 struct nfstat_args { 1358 int fd; 1359 struct nstat *sb; 1360 }; 1361 #endif 1362 /* ARGSUSED */ 1363 int 1364 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1365 { 1366 struct nstat nub; 1367 struct stat ub; 1368 int error; 1369 1370 error = kern_fstat(td, uap->fd, &ub); 1371 if (error == 0) { 1372 cvtnstat(&ub, &nub); 1373 error = copyout(&nub, uap->sb, sizeof(nub)); 1374 } 1375 return (error); 1376 } 1377 1378 /* 1379 * Return pathconf information about a file descriptor. 1380 */ 1381 #ifndef _SYS_SYSPROTO_H_ 1382 struct fpathconf_args { 1383 int fd; 1384 int name; 1385 }; 1386 #endif 1387 /* ARGSUSED */ 1388 int 1389 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1390 { 1391 struct file *fp; 1392 struct vnode *vp; 1393 cap_rights_t rights; 1394 int error; 1395 1396 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1397 if (error != 0) 1398 return (error); 1399 1400 if (uap->name == _PC_ASYNC_IO) { 1401 td->td_retval[0] = _POSIX_ASYNCHRONOUS_IO; 1402 goto out; 1403 } 1404 vp = fp->f_vnode; 1405 if (vp != NULL) { 1406 vn_lock(vp, LK_SHARED | LK_RETRY); 1407 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1408 VOP_UNLOCK(vp, 0); 1409 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1410 if (uap->name != _PC_PIPE_BUF) { 1411 error = EINVAL; 1412 } else { 1413 td->td_retval[0] = PIPE_BUF; 1414 error = 0; 1415 } 1416 } else { 1417 error = EOPNOTSUPP; 1418 } 1419 out: 1420 fdrop(fp, td); 1421 return (error); 1422 } 1423 1424 /* 1425 * Initialize filecaps structure. 1426 */ 1427 void 1428 filecaps_init(struct filecaps *fcaps) 1429 { 1430 1431 bzero(fcaps, sizeof(*fcaps)); 1432 fcaps->fc_nioctls = -1; 1433 } 1434 1435 /* 1436 * Copy filecaps structure allocating memory for ioctls array if needed. 1437 * 1438 * The last parameter indicates whether the fdtable is locked. If it is not and 1439 * ioctls are encountered, copying fails and the caller must lock the table. 1440 * 1441 * Note that if the table was not locked, the caller has to check the relevant 1442 * sequence counter to determine whether the operation was successful. 1443 */ 1444 int 1445 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked) 1446 { 1447 size_t size; 1448 1449 *dst = *src; 1450 if (src->fc_ioctls == NULL) 1451 return (0); 1452 if (!locked) 1453 return (1); 1454 1455 KASSERT(src->fc_nioctls > 0, 1456 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1457 1458 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1459 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1460 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1461 return (0); 1462 } 1463 1464 /* 1465 * Move filecaps structure to the new place and clear the old place. 1466 */ 1467 void 1468 filecaps_move(struct filecaps *src, struct filecaps *dst) 1469 { 1470 1471 *dst = *src; 1472 bzero(src, sizeof(*src)); 1473 } 1474 1475 /* 1476 * Fill the given filecaps structure with full rights. 1477 */ 1478 static void 1479 filecaps_fill(struct filecaps *fcaps) 1480 { 1481 1482 CAP_ALL(&fcaps->fc_rights); 1483 fcaps->fc_ioctls = NULL; 1484 fcaps->fc_nioctls = -1; 1485 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1486 } 1487 1488 /* 1489 * Free memory allocated within filecaps structure. 1490 */ 1491 void 1492 filecaps_free(struct filecaps *fcaps) 1493 { 1494 1495 free(fcaps->fc_ioctls, M_FILECAPS); 1496 bzero(fcaps, sizeof(*fcaps)); 1497 } 1498 1499 /* 1500 * Validate the given filecaps structure. 1501 */ 1502 static void 1503 filecaps_validate(const struct filecaps *fcaps, const char *func) 1504 { 1505 1506 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1507 ("%s: invalid rights", func)); 1508 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1509 ("%s: invalid fcntls", func)); 1510 KASSERT(fcaps->fc_fcntls == 0 || 1511 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1512 ("%s: fcntls without CAP_FCNTL", func)); 1513 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1514 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1515 ("%s: invalid ioctls", func)); 1516 KASSERT(fcaps->fc_nioctls == 0 || 1517 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1518 ("%s: ioctls without CAP_IOCTL", func)); 1519 } 1520 1521 static void 1522 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1523 { 1524 int nfd1; 1525 1526 FILEDESC_XLOCK_ASSERT(fdp); 1527 1528 nfd1 = fdp->fd_nfiles * 2; 1529 if (nfd1 < nfd) 1530 nfd1 = nfd; 1531 fdgrowtable(fdp, nfd1); 1532 } 1533 1534 /* 1535 * Grow the file table to accommodate (at least) nfd descriptors. 1536 */ 1537 static void 1538 fdgrowtable(struct filedesc *fdp, int nfd) 1539 { 1540 struct filedesc0 *fdp0; 1541 struct freetable *ft; 1542 struct fdescenttbl *ntable; 1543 struct fdescenttbl *otable; 1544 int nnfiles, onfiles; 1545 NDSLOTTYPE *nmap, *omap; 1546 1547 /* 1548 * If lastfile is -1 this struct filedesc was just allocated and we are 1549 * growing it to accommodate for the one we are going to copy from. There 1550 * is no need to have a lock on this one as it's not visible to anyone. 1551 */ 1552 if (fdp->fd_lastfile != -1) 1553 FILEDESC_XLOCK_ASSERT(fdp); 1554 1555 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1556 1557 /* save old values */ 1558 onfiles = fdp->fd_nfiles; 1559 otable = fdp->fd_files; 1560 omap = fdp->fd_map; 1561 1562 /* compute the size of the new table */ 1563 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1564 if (nnfiles <= onfiles) 1565 /* the table is already large enough */ 1566 return; 1567 1568 /* 1569 * Allocate a new table. We need enough space for the number of 1570 * entries, file entries themselves and the struct freetable we will use 1571 * when we decommission the table and place it on the freelist. 1572 * We place the struct freetable in the middle so we don't have 1573 * to worry about padding. 1574 */ 1575 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) + 1576 nnfiles * sizeof(ntable->fdt_ofiles[0]) + 1577 sizeof(struct freetable), 1578 M_FILEDESC, M_ZERO | M_WAITOK); 1579 /* copy the old data */ 1580 ntable->fdt_nfiles = nnfiles; 1581 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles, 1582 onfiles * sizeof(ntable->fdt_ofiles[0])); 1583 1584 /* 1585 * Allocate a new map only if the old is not large enough. It will 1586 * grow at a slower rate than the table as it can map more 1587 * entries than the table can hold. 1588 */ 1589 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1590 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1591 M_ZERO | M_WAITOK); 1592 /* copy over the old data and update the pointer */ 1593 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1594 fdp->fd_map = nmap; 1595 } 1596 1597 /* 1598 * Make sure that ntable is correctly initialized before we replace 1599 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent 1600 * data. 1601 */ 1602 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable); 1603 1604 /* 1605 * Do not free the old file table, as some threads may still 1606 * reference entries within it. Instead, place it on a freelist 1607 * which will be processed when the struct filedesc is released. 1608 * 1609 * Note that if onfiles == NDFILE, we're dealing with the original 1610 * static allocation contained within (struct filedesc0 *)fdp, 1611 * which must not be freed. 1612 */ 1613 if (onfiles > NDFILE) { 1614 ft = (struct freetable *)&otable->fdt_ofiles[onfiles]; 1615 fdp0 = (struct filedesc0 *)fdp; 1616 ft->ft_table = otable; 1617 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1618 } 1619 /* 1620 * The map does not have the same possibility of threads still 1621 * holding references to it. So always free it as long as it 1622 * does not reference the original static allocation. 1623 */ 1624 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1625 free(omap, M_FILEDESC); 1626 } 1627 1628 /* 1629 * Allocate a file descriptor for the process. 1630 */ 1631 int 1632 fdalloc(struct thread *td, int minfd, int *result) 1633 { 1634 struct proc *p = td->td_proc; 1635 struct filedesc *fdp = p->p_fd; 1636 int fd, maxfd, allocfd; 1637 #ifdef RACCT 1638 int error; 1639 #endif 1640 1641 FILEDESC_XLOCK_ASSERT(fdp); 1642 1643 if (fdp->fd_freefile > minfd) 1644 minfd = fdp->fd_freefile; 1645 1646 maxfd = getmaxfd(td); 1647 1648 /* 1649 * Search the bitmap for a free descriptor starting at minfd. 1650 * If none is found, grow the file table. 1651 */ 1652 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1653 if (fd >= maxfd) 1654 return (EMFILE); 1655 if (fd >= fdp->fd_nfiles) { 1656 allocfd = min(fd * 2, maxfd); 1657 #ifdef RACCT 1658 if (racct_enable) { 1659 PROC_LOCK(p); 1660 error = racct_set(p, RACCT_NOFILE, allocfd); 1661 PROC_UNLOCK(p); 1662 if (error != 0) 1663 return (EMFILE); 1664 } 1665 #endif 1666 /* 1667 * fd is already equal to first free descriptor >= minfd, so 1668 * we only need to grow the table and we are done. 1669 */ 1670 fdgrowtable_exp(fdp, allocfd); 1671 } 1672 1673 /* 1674 * Perform some sanity checks, then mark the file descriptor as 1675 * used and return it to the caller. 1676 */ 1677 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1678 ("invalid descriptor %d", fd)); 1679 KASSERT(!fdisused(fdp, fd), 1680 ("fd_first_free() returned non-free descriptor")); 1681 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1682 ("file descriptor isn't free")); 1683 fdused(fdp, fd); 1684 *result = fd; 1685 return (0); 1686 } 1687 1688 /* 1689 * Allocate n file descriptors for the process. 1690 */ 1691 int 1692 fdallocn(struct thread *td, int minfd, int *fds, int n) 1693 { 1694 struct proc *p = td->td_proc; 1695 struct filedesc *fdp = p->p_fd; 1696 int i; 1697 1698 FILEDESC_XLOCK_ASSERT(fdp); 1699 1700 for (i = 0; i < n; i++) 1701 if (fdalloc(td, 0, &fds[i]) != 0) 1702 break; 1703 1704 if (i < n) { 1705 for (i--; i >= 0; i--) 1706 fdunused(fdp, fds[i]); 1707 return (EMFILE); 1708 } 1709 1710 return (0); 1711 } 1712 1713 /* 1714 * Create a new open file structure and allocate a file descriptor for the 1715 * process that refers to it. We add one reference to the file for the 1716 * descriptor table and one reference for resultfp. This is to prevent us 1717 * being preempted and the entry in the descriptor table closed after we 1718 * release the FILEDESC lock. 1719 */ 1720 int 1721 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags, 1722 struct filecaps *fcaps) 1723 { 1724 struct file *fp; 1725 int error, fd; 1726 1727 error = falloc_noinstall(td, &fp); 1728 if (error) 1729 return (error); /* no reference held on error */ 1730 1731 error = finstall(td, fp, &fd, flags, fcaps); 1732 if (error) { 1733 fdrop(fp, td); /* one reference (fp only) */ 1734 return (error); 1735 } 1736 1737 if (resultfp != NULL) 1738 *resultfp = fp; /* copy out result */ 1739 else 1740 fdrop(fp, td); /* release local reference */ 1741 1742 if (resultfd != NULL) 1743 *resultfd = fd; 1744 1745 return (0); 1746 } 1747 1748 /* 1749 * Create a new open file structure without allocating a file descriptor. 1750 */ 1751 int 1752 falloc_noinstall(struct thread *td, struct file **resultfp) 1753 { 1754 struct file *fp; 1755 int maxuserfiles = maxfiles - (maxfiles / 20); 1756 int openfiles_new; 1757 static struct timeval lastfail; 1758 static int curfail; 1759 1760 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1761 1762 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1; 1763 if ((openfiles_new >= maxuserfiles && 1764 priv_check(td, PRIV_MAXFILES) != 0) || 1765 openfiles_new >= maxfiles) { 1766 atomic_subtract_int(&openfiles, 1); 1767 if (ppsratecheck(&lastfail, &curfail, 1)) { 1768 printf("kern.maxfiles limit exceeded by uid %i, (%s) " 1769 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm); 1770 } 1771 return (ENFILE); 1772 } 1773 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1774 refcount_init(&fp->f_count, 1); 1775 fp->f_cred = crhold(td->td_ucred); 1776 fp->f_ops = &badfileops; 1777 *resultfp = fp; 1778 return (0); 1779 } 1780 1781 /* 1782 * Install a file in a file descriptor table. 1783 */ 1784 void 1785 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags, 1786 struct filecaps *fcaps) 1787 { 1788 struct filedescent *fde; 1789 1790 MPASS(fp != NULL); 1791 if (fcaps != NULL) 1792 filecaps_validate(fcaps, __func__); 1793 FILEDESC_XLOCK_ASSERT(fdp); 1794 1795 fde = &fdp->fd_ofiles[fd]; 1796 #ifdef CAPABILITIES 1797 seq_write_begin(&fde->fde_seq); 1798 #endif 1799 fde->fde_file = fp; 1800 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0; 1801 if (fcaps != NULL) 1802 filecaps_move(fcaps, &fde->fde_caps); 1803 else 1804 filecaps_fill(&fde->fde_caps); 1805 #ifdef CAPABILITIES 1806 seq_write_end(&fde->fde_seq); 1807 #endif 1808 } 1809 1810 int 1811 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1812 struct filecaps *fcaps) 1813 { 1814 struct filedesc *fdp = td->td_proc->p_fd; 1815 int error; 1816 1817 MPASS(fd != NULL); 1818 1819 FILEDESC_XLOCK(fdp); 1820 if ((error = fdalloc(td, 0, fd))) { 1821 FILEDESC_XUNLOCK(fdp); 1822 return (error); 1823 } 1824 fhold(fp); 1825 _finstall(fdp, fp, *fd, flags, fcaps); 1826 FILEDESC_XUNLOCK(fdp); 1827 return (0); 1828 } 1829 1830 /* 1831 * Build a new filedesc structure from another. 1832 * Copy the current, root, and jail root vnode references. 1833 * 1834 * If fdp is not NULL, return with it shared locked. 1835 */ 1836 struct filedesc * 1837 fdinit(struct filedesc *fdp, bool prepfiles) 1838 { 1839 struct filedesc0 *newfdp0; 1840 struct filedesc *newfdp; 1841 1842 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO); 1843 newfdp = &newfdp0->fd_fd; 1844 1845 /* Create the file descriptor table. */ 1846 FILEDESC_LOCK_INIT(newfdp); 1847 refcount_init(&newfdp->fd_refcnt, 1); 1848 refcount_init(&newfdp->fd_holdcnt, 1); 1849 newfdp->fd_cmask = CMASK; 1850 newfdp->fd_map = newfdp0->fd_dmap; 1851 newfdp->fd_lastfile = -1; 1852 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles; 1853 newfdp->fd_files->fdt_nfiles = NDFILE; 1854 1855 if (fdp == NULL) 1856 return (newfdp); 1857 1858 if (prepfiles && fdp->fd_lastfile >= newfdp->fd_nfiles) 1859 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1860 1861 FILEDESC_SLOCK(fdp); 1862 newfdp->fd_cdir = fdp->fd_cdir; 1863 if (newfdp->fd_cdir) 1864 vrefact(newfdp->fd_cdir); 1865 newfdp->fd_rdir = fdp->fd_rdir; 1866 if (newfdp->fd_rdir) 1867 vrefact(newfdp->fd_rdir); 1868 newfdp->fd_jdir = fdp->fd_jdir; 1869 if (newfdp->fd_jdir) 1870 vrefact(newfdp->fd_jdir); 1871 1872 if (!prepfiles) { 1873 FILEDESC_SUNLOCK(fdp); 1874 } else { 1875 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1876 FILEDESC_SUNLOCK(fdp); 1877 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1878 FILEDESC_SLOCK(fdp); 1879 } 1880 } 1881 1882 return (newfdp); 1883 } 1884 1885 static struct filedesc * 1886 fdhold(struct proc *p) 1887 { 1888 struct filedesc *fdp; 1889 1890 PROC_LOCK_ASSERT(p, MA_OWNED); 1891 fdp = p->p_fd; 1892 if (fdp != NULL) 1893 refcount_acquire(&fdp->fd_holdcnt); 1894 return (fdp); 1895 } 1896 1897 static void 1898 fddrop(struct filedesc *fdp) 1899 { 1900 1901 if (fdp->fd_holdcnt > 1) { 1902 if (refcount_release(&fdp->fd_holdcnt) == 0) 1903 return; 1904 } 1905 1906 FILEDESC_LOCK_DESTROY(fdp); 1907 uma_zfree(filedesc0_zone, fdp); 1908 } 1909 1910 /* 1911 * Share a filedesc structure. 1912 */ 1913 struct filedesc * 1914 fdshare(struct filedesc *fdp) 1915 { 1916 1917 refcount_acquire(&fdp->fd_refcnt); 1918 return (fdp); 1919 } 1920 1921 /* 1922 * Unshare a filedesc structure, if necessary by making a copy 1923 */ 1924 void 1925 fdunshare(struct thread *td) 1926 { 1927 struct filedesc *tmp; 1928 struct proc *p = td->td_proc; 1929 1930 if (p->p_fd->fd_refcnt == 1) 1931 return; 1932 1933 tmp = fdcopy(p->p_fd); 1934 fdescfree(td); 1935 p->p_fd = tmp; 1936 } 1937 1938 void 1939 fdinstall_remapped(struct thread *td, struct filedesc *fdp) 1940 { 1941 1942 fdescfree(td); 1943 td->td_proc->p_fd = fdp; 1944 } 1945 1946 /* 1947 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1948 * this is to ease callers, not catch errors. 1949 */ 1950 struct filedesc * 1951 fdcopy(struct filedesc *fdp) 1952 { 1953 struct filedesc *newfdp; 1954 struct filedescent *nfde, *ofde; 1955 int i; 1956 1957 MPASS(fdp != NULL); 1958 1959 newfdp = fdinit(fdp, true); 1960 /* copy all passable descriptors (i.e. not kqueue) */ 1961 newfdp->fd_freefile = -1; 1962 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1963 ofde = &fdp->fd_ofiles[i]; 1964 if (ofde->fde_file == NULL || 1965 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) { 1966 if (newfdp->fd_freefile == -1) 1967 newfdp->fd_freefile = i; 1968 continue; 1969 } 1970 nfde = &newfdp->fd_ofiles[i]; 1971 *nfde = *ofde; 1972 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 1973 fhold(nfde->fde_file); 1974 fdused_init(newfdp, i); 1975 newfdp->fd_lastfile = i; 1976 } 1977 if (newfdp->fd_freefile == -1) 1978 newfdp->fd_freefile = i; 1979 newfdp->fd_cmask = fdp->fd_cmask; 1980 FILEDESC_SUNLOCK(fdp); 1981 return (newfdp); 1982 } 1983 1984 /* 1985 * Copies a filedesc structure, while remapping all file descriptors 1986 * stored inside using a translation table. 1987 * 1988 * File descriptors are copied over to the new file descriptor table, 1989 * regardless of whether the close-on-exec flag is set. 1990 */ 1991 int 1992 fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds, 1993 struct filedesc **ret) 1994 { 1995 struct filedesc *newfdp; 1996 struct filedescent *nfde, *ofde; 1997 int error, i; 1998 1999 MPASS(fdp != NULL); 2000 2001 newfdp = fdinit(fdp, true); 2002 if (nfds > fdp->fd_lastfile + 1) { 2003 /* New table cannot be larger than the old one. */ 2004 error = E2BIG; 2005 goto bad; 2006 } 2007 /* Copy all passable descriptors (i.e. not kqueue). */ 2008 newfdp->fd_freefile = nfds; 2009 for (i = 0; i < nfds; ++i) { 2010 if (fds[i] < 0 || fds[i] > fdp->fd_lastfile) { 2011 /* File descriptor out of bounds. */ 2012 error = EBADF; 2013 goto bad; 2014 } 2015 ofde = &fdp->fd_ofiles[fds[i]]; 2016 if (ofde->fde_file == NULL) { 2017 /* Unused file descriptor. */ 2018 error = EBADF; 2019 goto bad; 2020 } 2021 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) { 2022 /* File descriptor cannot be passed. */ 2023 error = EINVAL; 2024 goto bad; 2025 } 2026 nfde = &newfdp->fd_ofiles[i]; 2027 *nfde = *ofde; 2028 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 2029 fhold(nfde->fde_file); 2030 fdused_init(newfdp, i); 2031 newfdp->fd_lastfile = i; 2032 } 2033 newfdp->fd_cmask = fdp->fd_cmask; 2034 FILEDESC_SUNLOCK(fdp); 2035 *ret = newfdp; 2036 return (0); 2037 bad: 2038 FILEDESC_SUNLOCK(fdp); 2039 fdescfree_remapped(newfdp); 2040 return (error); 2041 } 2042 2043 /* 2044 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e. 2045 * one of processes using it exits) and the table used to be shared. 2046 */ 2047 static void 2048 fdclearlocks(struct thread *td) 2049 { 2050 struct filedesc *fdp; 2051 struct filedesc_to_leader *fdtol; 2052 struct flock lf; 2053 struct file *fp; 2054 struct proc *p; 2055 struct vnode *vp; 2056 int i; 2057 2058 p = td->td_proc; 2059 fdp = p->p_fd; 2060 fdtol = p->p_fdtol; 2061 MPASS(fdtol != NULL); 2062 2063 FILEDESC_XLOCK(fdp); 2064 KASSERT(fdtol->fdl_refcount > 0, 2065 ("filedesc_to_refcount botch: fdl_refcount=%d", 2066 fdtol->fdl_refcount)); 2067 if (fdtol->fdl_refcount == 1 && 2068 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2069 for (i = 0; i <= fdp->fd_lastfile; i++) { 2070 fp = fdp->fd_ofiles[i].fde_file; 2071 if (fp == NULL || fp->f_type != DTYPE_VNODE) 2072 continue; 2073 fhold(fp); 2074 FILEDESC_XUNLOCK(fdp); 2075 lf.l_whence = SEEK_SET; 2076 lf.l_start = 0; 2077 lf.l_len = 0; 2078 lf.l_type = F_UNLCK; 2079 vp = fp->f_vnode; 2080 (void) VOP_ADVLOCK(vp, 2081 (caddr_t)p->p_leader, F_UNLCK, 2082 &lf, F_POSIX); 2083 FILEDESC_XLOCK(fdp); 2084 fdrop(fp, td); 2085 } 2086 } 2087 retry: 2088 if (fdtol->fdl_refcount == 1) { 2089 if (fdp->fd_holdleaderscount > 0 && 2090 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2091 /* 2092 * close() or kern_dup() has cleared a reference 2093 * in a shared file descriptor table. 2094 */ 2095 fdp->fd_holdleaderswakeup = 1; 2096 sx_sleep(&fdp->fd_holdleaderscount, 2097 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2098 goto retry; 2099 } 2100 if (fdtol->fdl_holdcount > 0) { 2101 /* 2102 * Ensure that fdtol->fdl_leader remains 2103 * valid in closef(). 2104 */ 2105 fdtol->fdl_wakeup = 1; 2106 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2107 "fdlhold", 0); 2108 goto retry; 2109 } 2110 } 2111 fdtol->fdl_refcount--; 2112 if (fdtol->fdl_refcount == 0 && 2113 fdtol->fdl_holdcount == 0) { 2114 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2115 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2116 } else 2117 fdtol = NULL; 2118 p->p_fdtol = NULL; 2119 FILEDESC_XUNLOCK(fdp); 2120 if (fdtol != NULL) 2121 free(fdtol, M_FILEDESC_TO_LEADER); 2122 } 2123 2124 /* 2125 * Release a filedesc structure. 2126 */ 2127 static void 2128 fdescfree_fds(struct thread *td, struct filedesc *fdp, bool needclose) 2129 { 2130 struct filedesc0 *fdp0; 2131 struct freetable *ft, *tft; 2132 struct filedescent *fde; 2133 struct file *fp; 2134 int i; 2135 2136 for (i = 0; i <= fdp->fd_lastfile; i++) { 2137 fde = &fdp->fd_ofiles[i]; 2138 fp = fde->fde_file; 2139 if (fp != NULL) { 2140 fdefree_last(fde); 2141 if (needclose) 2142 (void) closef(fp, td); 2143 else 2144 fdrop(fp, td); 2145 } 2146 } 2147 2148 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2149 free(fdp->fd_map, M_FILEDESC); 2150 if (fdp->fd_nfiles > NDFILE) 2151 free(fdp->fd_files, M_FILEDESC); 2152 2153 fdp0 = (struct filedesc0 *)fdp; 2154 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft) 2155 free(ft->ft_table, M_FILEDESC); 2156 2157 fddrop(fdp); 2158 } 2159 2160 void 2161 fdescfree(struct thread *td) 2162 { 2163 struct proc *p; 2164 struct filedesc *fdp; 2165 struct vnode *cdir, *jdir, *rdir; 2166 2167 p = td->td_proc; 2168 fdp = p->p_fd; 2169 MPASS(fdp != NULL); 2170 2171 #ifdef RACCT 2172 if (racct_enable) { 2173 PROC_LOCK(p); 2174 racct_set(p, RACCT_NOFILE, 0); 2175 PROC_UNLOCK(p); 2176 } 2177 #endif 2178 2179 if (p->p_fdtol != NULL) 2180 fdclearlocks(td); 2181 2182 PROC_LOCK(p); 2183 p->p_fd = NULL; 2184 PROC_UNLOCK(p); 2185 2186 if (refcount_release(&fdp->fd_refcnt) == 0) 2187 return; 2188 2189 FILEDESC_XLOCK(fdp); 2190 cdir = fdp->fd_cdir; 2191 fdp->fd_cdir = NULL; 2192 rdir = fdp->fd_rdir; 2193 fdp->fd_rdir = NULL; 2194 jdir = fdp->fd_jdir; 2195 fdp->fd_jdir = NULL; 2196 FILEDESC_XUNLOCK(fdp); 2197 2198 if (cdir != NULL) 2199 vrele(cdir); 2200 if (rdir != NULL) 2201 vrele(rdir); 2202 if (jdir != NULL) 2203 vrele(jdir); 2204 2205 fdescfree_fds(td, fdp, 1); 2206 } 2207 2208 void 2209 fdescfree_remapped(struct filedesc *fdp) 2210 { 2211 2212 if (fdp->fd_cdir != NULL) 2213 vrele(fdp->fd_cdir); 2214 if (fdp->fd_rdir != NULL) 2215 vrele(fdp->fd_rdir); 2216 if (fdp->fd_jdir != NULL) 2217 vrele(fdp->fd_jdir); 2218 2219 fdescfree_fds(curthread, fdp, 0); 2220 } 2221 2222 /* 2223 * For setugid programs, we don't want to people to use that setugidness 2224 * to generate error messages which write to a file which otherwise would 2225 * otherwise be off-limits to the process. We check for filesystems where 2226 * the vnode can change out from under us after execve (like [lin]procfs). 2227 * 2228 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is 2229 * sufficient. We also don't check for setugidness since we know we are. 2230 */ 2231 static bool 2232 is_unsafe(struct file *fp) 2233 { 2234 struct vnode *vp; 2235 2236 if (fp->f_type != DTYPE_VNODE) 2237 return (false); 2238 2239 vp = fp->f_vnode; 2240 return ((vp->v_vflag & VV_PROCDEP) != 0); 2241 } 2242 2243 /* 2244 * Make this setguid thing safe, if at all possible. 2245 */ 2246 void 2247 fdsetugidsafety(struct thread *td) 2248 { 2249 struct filedesc *fdp; 2250 struct file *fp; 2251 int i; 2252 2253 fdp = td->td_proc->p_fd; 2254 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2255 MPASS(fdp->fd_nfiles >= 3); 2256 for (i = 0; i <= 2; i++) { 2257 fp = fdp->fd_ofiles[i].fde_file; 2258 if (fp != NULL && is_unsafe(fp)) { 2259 FILEDESC_XLOCK(fdp); 2260 knote_fdclose(td, i); 2261 /* 2262 * NULL-out descriptor prior to close to avoid 2263 * a race while close blocks. 2264 */ 2265 fdfree(fdp, i); 2266 FILEDESC_XUNLOCK(fdp); 2267 (void) closef(fp, td); 2268 } 2269 } 2270 } 2271 2272 /* 2273 * If a specific file object occupies a specific file descriptor, close the 2274 * file descriptor entry and drop a reference on the file object. This is a 2275 * convenience function to handle a subsequent error in a function that calls 2276 * falloc() that handles the race that another thread might have closed the 2277 * file descriptor out from under the thread creating the file object. 2278 */ 2279 void 2280 fdclose(struct thread *td, struct file *fp, int idx) 2281 { 2282 struct filedesc *fdp = td->td_proc->p_fd; 2283 2284 FILEDESC_XLOCK(fdp); 2285 if (fdp->fd_ofiles[idx].fde_file == fp) { 2286 fdfree(fdp, idx); 2287 FILEDESC_XUNLOCK(fdp); 2288 fdrop(fp, td); 2289 } else 2290 FILEDESC_XUNLOCK(fdp); 2291 } 2292 2293 /* 2294 * Close any files on exec? 2295 */ 2296 void 2297 fdcloseexec(struct thread *td) 2298 { 2299 struct filedesc *fdp; 2300 struct filedescent *fde; 2301 struct file *fp; 2302 int i; 2303 2304 fdp = td->td_proc->p_fd; 2305 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2306 for (i = 0; i <= fdp->fd_lastfile; i++) { 2307 fde = &fdp->fd_ofiles[i]; 2308 fp = fde->fde_file; 2309 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2310 (fde->fde_flags & UF_EXCLOSE))) { 2311 FILEDESC_XLOCK(fdp); 2312 fdfree(fdp, i); 2313 (void) closefp(fdp, i, fp, td, 0); 2314 FILEDESC_UNLOCK_ASSERT(fdp); 2315 } 2316 } 2317 } 2318 2319 /* 2320 * It is unsafe for set[ug]id processes to be started with file 2321 * descriptors 0..2 closed, as these descriptors are given implicit 2322 * significance in the Standard C library. fdcheckstd() will create a 2323 * descriptor referencing /dev/null for each of stdin, stdout, and 2324 * stderr that is not already open. 2325 */ 2326 int 2327 fdcheckstd(struct thread *td) 2328 { 2329 struct filedesc *fdp; 2330 register_t save; 2331 int i, error, devnull; 2332 2333 fdp = td->td_proc->p_fd; 2334 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2335 MPASS(fdp->fd_nfiles >= 3); 2336 devnull = -1; 2337 for (i = 0; i <= 2; i++) { 2338 if (fdp->fd_ofiles[i].fde_file != NULL) 2339 continue; 2340 2341 save = td->td_retval[0]; 2342 if (devnull != -1) { 2343 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i); 2344 } else { 2345 error = kern_openat(td, AT_FDCWD, "/dev/null", 2346 UIO_SYSSPACE, O_RDWR, 0); 2347 if (error == 0) { 2348 devnull = td->td_retval[0]; 2349 KASSERT(devnull == i, ("we didn't get our fd")); 2350 } 2351 } 2352 td->td_retval[0] = save; 2353 if (error != 0) 2354 return (error); 2355 } 2356 return (0); 2357 } 2358 2359 /* 2360 * Internal form of close. Decrement reference count on file structure. 2361 * Note: td may be NULL when closing a file that was being passed in a 2362 * message. 2363 * 2364 * XXXRW: Giant is not required for the caller, but often will be held; this 2365 * makes it moderately likely the Giant will be recursed in the VFS case. 2366 */ 2367 int 2368 closef(struct file *fp, struct thread *td) 2369 { 2370 struct vnode *vp; 2371 struct flock lf; 2372 struct filedesc_to_leader *fdtol; 2373 struct filedesc *fdp; 2374 2375 /* 2376 * POSIX record locking dictates that any close releases ALL 2377 * locks owned by this process. This is handled by setting 2378 * a flag in the unlock to free ONLY locks obeying POSIX 2379 * semantics, and not to free BSD-style file locks. 2380 * If the descriptor was in a message, POSIX-style locks 2381 * aren't passed with the descriptor, and the thread pointer 2382 * will be NULL. Callers should be careful only to pass a 2383 * NULL thread pointer when there really is no owning 2384 * context that might have locks, or the locks will be 2385 * leaked. 2386 */ 2387 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2388 vp = fp->f_vnode; 2389 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2390 lf.l_whence = SEEK_SET; 2391 lf.l_start = 0; 2392 lf.l_len = 0; 2393 lf.l_type = F_UNLCK; 2394 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2395 F_UNLCK, &lf, F_POSIX); 2396 } 2397 fdtol = td->td_proc->p_fdtol; 2398 if (fdtol != NULL) { 2399 /* 2400 * Handle special case where file descriptor table is 2401 * shared between multiple process leaders. 2402 */ 2403 fdp = td->td_proc->p_fd; 2404 FILEDESC_XLOCK(fdp); 2405 for (fdtol = fdtol->fdl_next; 2406 fdtol != td->td_proc->p_fdtol; 2407 fdtol = fdtol->fdl_next) { 2408 if ((fdtol->fdl_leader->p_flag & 2409 P_ADVLOCK) == 0) 2410 continue; 2411 fdtol->fdl_holdcount++; 2412 FILEDESC_XUNLOCK(fdp); 2413 lf.l_whence = SEEK_SET; 2414 lf.l_start = 0; 2415 lf.l_len = 0; 2416 lf.l_type = F_UNLCK; 2417 vp = fp->f_vnode; 2418 (void) VOP_ADVLOCK(vp, 2419 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2420 F_POSIX); 2421 FILEDESC_XLOCK(fdp); 2422 fdtol->fdl_holdcount--; 2423 if (fdtol->fdl_holdcount == 0 && 2424 fdtol->fdl_wakeup != 0) { 2425 fdtol->fdl_wakeup = 0; 2426 wakeup(fdtol); 2427 } 2428 } 2429 FILEDESC_XUNLOCK(fdp); 2430 } 2431 } 2432 return (fdrop(fp, td)); 2433 } 2434 2435 /* 2436 * Initialize the file pointer with the specified properties. 2437 * 2438 * The ops are set with release semantics to be certain that the flags, type, 2439 * and data are visible when ops is. This is to prevent ops methods from being 2440 * called with bad data. 2441 */ 2442 void 2443 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2444 { 2445 fp->f_data = data; 2446 fp->f_flag = flag; 2447 fp->f_type = type; 2448 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2449 } 2450 2451 int 2452 fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2453 struct file **fpp, struct filecaps *havecapsp) 2454 { 2455 struct filedescent *fde; 2456 int error; 2457 2458 FILEDESC_LOCK_ASSERT(fdp); 2459 2460 fde = fdeget_locked(fdp, fd); 2461 if (fde == NULL) { 2462 error = EBADF; 2463 goto out; 2464 } 2465 2466 #ifdef CAPABILITIES 2467 error = cap_check(cap_rights_fde(fde), needrightsp); 2468 if (error != 0) 2469 goto out; 2470 #endif 2471 2472 if (havecapsp != NULL) 2473 filecaps_copy(&fde->fde_caps, havecapsp, true); 2474 2475 *fpp = fde->fde_file; 2476 2477 error = 0; 2478 out: 2479 return (error); 2480 } 2481 2482 int 2483 fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp, 2484 struct file **fpp, struct filecaps *havecapsp) 2485 { 2486 struct filedesc *fdp = td->td_proc->p_fd; 2487 int error; 2488 #ifndef CAPABILITIES 2489 error = fget_unlocked(fdp, fd, needrightsp, fpp, NULL); 2490 if (error == 0 && havecapsp != NULL) 2491 filecaps_fill(havecapsp); 2492 #else 2493 struct file *fp; 2494 seq_t seq; 2495 2496 for (;;) { 2497 error = fget_unlocked(fdp, fd, needrightsp, &fp, &seq); 2498 if (error != 0) 2499 return (error); 2500 2501 if (havecapsp != NULL) { 2502 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, 2503 havecapsp, false)) { 2504 fdrop(fp, td); 2505 goto get_locked; 2506 } 2507 } 2508 2509 if (!fd_modified(fdp, fd, seq)) 2510 break; 2511 fdrop(fp, td); 2512 } 2513 2514 *fpp = fp; 2515 return (0); 2516 2517 get_locked: 2518 FILEDESC_SLOCK(fdp); 2519 error = fget_cap_locked(fdp, fd, needrightsp, fpp, havecapsp); 2520 if (error == 0) 2521 fhold(*fpp); 2522 FILEDESC_SUNLOCK(fdp); 2523 #endif 2524 return (error); 2525 } 2526 2527 int 2528 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2529 struct file **fpp, seq_t *seqp) 2530 { 2531 #ifdef CAPABILITIES 2532 struct filedescent *fde; 2533 #endif 2534 struct fdescenttbl *fdt; 2535 struct file *fp; 2536 u_int count; 2537 #ifdef CAPABILITIES 2538 seq_t seq; 2539 cap_rights_t haverights; 2540 int error; 2541 #endif 2542 2543 fdt = fdp->fd_files; 2544 if ((u_int)fd >= fdt->fdt_nfiles) 2545 return (EBADF); 2546 /* 2547 * Fetch the descriptor locklessly. We avoid fdrop() races by 2548 * never raising a refcount above 0. To accomplish this we have 2549 * to use a cmpset loop rather than an atomic_add. The descriptor 2550 * must be re-verified once we acquire a reference to be certain 2551 * that the identity is still correct and we did not lose a race 2552 * due to preemption. 2553 */ 2554 for (;;) { 2555 #ifdef CAPABILITIES 2556 seq = seq_read(fd_seq(fdt, fd)); 2557 fde = &fdt->fdt_ofiles[fd]; 2558 haverights = *cap_rights_fde(fde); 2559 fp = fde->fde_file; 2560 if (!seq_consistent(fd_seq(fdt, fd), seq)) 2561 continue; 2562 #else 2563 fp = fdt->fdt_ofiles[fd].fde_file; 2564 #endif 2565 if (fp == NULL) 2566 return (EBADF); 2567 #ifdef CAPABILITIES 2568 error = cap_check(&haverights, needrightsp); 2569 if (error != 0) 2570 return (error); 2571 #endif 2572 count = fp->f_count; 2573 retry: 2574 if (count == 0) { 2575 /* 2576 * Force a reload. Other thread could reallocate the 2577 * table before this fd was closed, so it possible that 2578 * there is a stale fp pointer in cached version. 2579 */ 2580 fdt = *(struct fdescenttbl * volatile *)&(fdp->fd_files); 2581 continue; 2582 } 2583 /* 2584 * Use an acquire barrier to force re-reading of fdt so it is 2585 * refreshed for verification. 2586 */ 2587 if (atomic_fcmpset_acq_int(&fp->f_count, &count, count + 1) == 0) 2588 goto retry; 2589 fdt = fdp->fd_files; 2590 #ifdef CAPABILITIES 2591 if (seq_consistent_nomb(fd_seq(fdt, fd), seq)) 2592 #else 2593 if (fp == fdt->fdt_ofiles[fd].fde_file) 2594 #endif 2595 break; 2596 fdrop(fp, curthread); 2597 } 2598 *fpp = fp; 2599 if (seqp != NULL) { 2600 #ifdef CAPABILITIES 2601 *seqp = seq; 2602 #endif 2603 } 2604 return (0); 2605 } 2606 2607 /* 2608 * Extract the file pointer associated with the specified descriptor for the 2609 * current user process. 2610 * 2611 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2612 * returned. 2613 * 2614 * File's rights will be checked against the capability rights mask. 2615 * 2616 * If an error occurred the non-zero error is returned and *fpp is set to 2617 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2618 * responsible for fdrop(). 2619 */ 2620 static __inline int 2621 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2622 cap_rights_t *needrightsp, seq_t *seqp) 2623 { 2624 struct filedesc *fdp; 2625 struct file *fp; 2626 int error; 2627 2628 *fpp = NULL; 2629 fdp = td->td_proc->p_fd; 2630 error = fget_unlocked(fdp, fd, needrightsp, &fp, seqp); 2631 if (error != 0) 2632 return (error); 2633 if (fp->f_ops == &badfileops) { 2634 fdrop(fp, td); 2635 return (EBADF); 2636 } 2637 2638 /* 2639 * FREAD and FWRITE failure return EBADF as per POSIX. 2640 */ 2641 error = 0; 2642 switch (flags) { 2643 case FREAD: 2644 case FWRITE: 2645 if ((fp->f_flag & flags) == 0) 2646 error = EBADF; 2647 break; 2648 case FEXEC: 2649 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2650 ((fp->f_flag & FWRITE) != 0)) 2651 error = EBADF; 2652 break; 2653 case 0: 2654 break; 2655 default: 2656 KASSERT(0, ("wrong flags")); 2657 } 2658 2659 if (error != 0) { 2660 fdrop(fp, td); 2661 return (error); 2662 } 2663 2664 *fpp = fp; 2665 return (0); 2666 } 2667 2668 int 2669 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2670 { 2671 2672 return (_fget(td, fd, fpp, 0, rightsp, NULL)); 2673 } 2674 2675 int 2676 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2677 struct file **fpp) 2678 { 2679 int error; 2680 #ifndef CAPABILITIES 2681 error = _fget(td, fd, fpp, 0, rightsp, NULL); 2682 if (maxprotp != NULL) 2683 *maxprotp = VM_PROT_ALL; 2684 #else 2685 struct filedesc *fdp = td->td_proc->p_fd; 2686 seq_t seq; 2687 2688 MPASS(cap_rights_is_set(rightsp, CAP_MMAP)); 2689 for (;;) { 2690 error = _fget(td, fd, fpp, 0, rightsp, &seq); 2691 if (error != 0) 2692 return (error); 2693 /* 2694 * If requested, convert capability rights to access flags. 2695 */ 2696 if (maxprotp != NULL) 2697 *maxprotp = cap_rights_to_vmprot(cap_rights(fdp, fd)); 2698 if (!fd_modified(fdp, fd, seq)) 2699 break; 2700 fdrop(*fpp, td); 2701 } 2702 #endif 2703 return (error); 2704 } 2705 2706 int 2707 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2708 { 2709 2710 return (_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2711 } 2712 2713 int 2714 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2715 { 2716 2717 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2718 } 2719 2720 int 2721 fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp, int needfcntl, 2722 struct file **fpp) 2723 { 2724 struct filedesc *fdp = td->td_proc->p_fd; 2725 #ifndef CAPABILITIES 2726 return (fget_unlocked(fdp, fd, rightsp, fpp, NULL)); 2727 #else 2728 int error; 2729 seq_t seq; 2730 2731 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL)); 2732 for (;;) { 2733 error = fget_unlocked(fdp, fd, rightsp, fpp, &seq); 2734 if (error != 0) 2735 return (error); 2736 error = cap_fcntl_check(fdp, fd, needfcntl); 2737 if (!fd_modified(fdp, fd, seq)) 2738 break; 2739 fdrop(*fpp, td); 2740 } 2741 if (error != 0) { 2742 fdrop(*fpp, td); 2743 *fpp = NULL; 2744 } 2745 return (error); 2746 #endif 2747 } 2748 2749 /* 2750 * Like fget() but loads the underlying vnode, or returns an error if the 2751 * descriptor does not represent a vnode. Note that pipes use vnodes but 2752 * never have VM objects. The returned vnode will be vref()'d. 2753 * 2754 * XXX: what about the unused flags ? 2755 */ 2756 static __inline int 2757 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2758 struct vnode **vpp) 2759 { 2760 struct file *fp; 2761 int error; 2762 2763 *vpp = NULL; 2764 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2765 if (error != 0) 2766 return (error); 2767 if (fp->f_vnode == NULL) { 2768 error = EINVAL; 2769 } else { 2770 *vpp = fp->f_vnode; 2771 vrefact(*vpp); 2772 } 2773 fdrop(fp, td); 2774 2775 return (error); 2776 } 2777 2778 int 2779 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2780 { 2781 2782 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2783 } 2784 2785 int 2786 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2787 struct filecaps *havecaps, struct vnode **vpp) 2788 { 2789 struct filedesc *fdp; 2790 struct filecaps caps; 2791 struct file *fp; 2792 int error; 2793 2794 fdp = td->td_proc->p_fd; 2795 error = fget_cap_locked(fdp, fd, needrightsp, &fp, &caps); 2796 if (error != 0) 2797 return (error); 2798 if (fp->f_ops == &badfileops) { 2799 error = EBADF; 2800 goto out; 2801 } 2802 if (fp->f_vnode == NULL) { 2803 error = EINVAL; 2804 goto out; 2805 } 2806 2807 *havecaps = caps; 2808 *vpp = fp->f_vnode; 2809 vrefact(*vpp); 2810 2811 return (0); 2812 out: 2813 filecaps_free(&caps); 2814 return (error); 2815 } 2816 2817 int 2818 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2819 { 2820 2821 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2822 } 2823 2824 int 2825 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2826 { 2827 2828 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2829 } 2830 2831 #ifdef notyet 2832 int 2833 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2834 struct vnode **vpp) 2835 { 2836 2837 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2838 } 2839 #endif 2840 2841 /* 2842 * Handle the last reference to a file being closed. 2843 */ 2844 int 2845 _fdrop(struct file *fp, struct thread *td) 2846 { 2847 int error; 2848 2849 if (fp->f_count != 0) 2850 panic("fdrop: count %d", fp->f_count); 2851 error = fo_close(fp, td); 2852 atomic_subtract_int(&openfiles, 1); 2853 crfree(fp->f_cred); 2854 free(fp->f_advice, M_FADVISE); 2855 uma_zfree(file_zone, fp); 2856 2857 return (error); 2858 } 2859 2860 /* 2861 * Apply an advisory lock on a file descriptor. 2862 * 2863 * Just attempt to get a record lock of the requested type on the entire file 2864 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2865 */ 2866 #ifndef _SYS_SYSPROTO_H_ 2867 struct flock_args { 2868 int fd; 2869 int how; 2870 }; 2871 #endif 2872 /* ARGSUSED */ 2873 int 2874 sys_flock(struct thread *td, struct flock_args *uap) 2875 { 2876 struct file *fp; 2877 struct vnode *vp; 2878 struct flock lf; 2879 cap_rights_t rights; 2880 int error; 2881 2882 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2883 if (error != 0) 2884 return (error); 2885 if (fp->f_type != DTYPE_VNODE) { 2886 fdrop(fp, td); 2887 return (EOPNOTSUPP); 2888 } 2889 2890 vp = fp->f_vnode; 2891 lf.l_whence = SEEK_SET; 2892 lf.l_start = 0; 2893 lf.l_len = 0; 2894 if (uap->how & LOCK_UN) { 2895 lf.l_type = F_UNLCK; 2896 atomic_clear_int(&fp->f_flag, FHASLOCK); 2897 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2898 goto done2; 2899 } 2900 if (uap->how & LOCK_EX) 2901 lf.l_type = F_WRLCK; 2902 else if (uap->how & LOCK_SH) 2903 lf.l_type = F_RDLCK; 2904 else { 2905 error = EBADF; 2906 goto done2; 2907 } 2908 atomic_set_int(&fp->f_flag, FHASLOCK); 2909 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2910 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2911 done2: 2912 fdrop(fp, td); 2913 return (error); 2914 } 2915 /* 2916 * Duplicate the specified descriptor to a free descriptor. 2917 */ 2918 int 2919 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2920 int openerror, int *indxp) 2921 { 2922 struct filedescent *newfde, *oldfde; 2923 struct file *fp; 2924 int error, indx; 2925 2926 KASSERT(openerror == ENODEV || openerror == ENXIO, 2927 ("unexpected error %d in %s", openerror, __func__)); 2928 2929 /* 2930 * If the to-be-dup'd fd number is greater than the allowed number 2931 * of file descriptors, or the fd to be dup'd has already been 2932 * closed, then reject. 2933 */ 2934 FILEDESC_XLOCK(fdp); 2935 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2936 FILEDESC_XUNLOCK(fdp); 2937 return (EBADF); 2938 } 2939 2940 error = fdalloc(td, 0, &indx); 2941 if (error != 0) { 2942 FILEDESC_XUNLOCK(fdp); 2943 return (error); 2944 } 2945 2946 /* 2947 * There are two cases of interest here. 2948 * 2949 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2950 * 2951 * For ENXIO steal away the file structure from (dfd) and store it in 2952 * (indx). (dfd) is effectively closed by this operation. 2953 */ 2954 switch (openerror) { 2955 case ENODEV: 2956 /* 2957 * Check that the mode the file is being opened for is a 2958 * subset of the mode of the existing descriptor. 2959 */ 2960 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2961 fdunused(fdp, indx); 2962 FILEDESC_XUNLOCK(fdp); 2963 return (EACCES); 2964 } 2965 fhold(fp); 2966 newfde = &fdp->fd_ofiles[indx]; 2967 oldfde = &fdp->fd_ofiles[dfd]; 2968 #ifdef CAPABILITIES 2969 seq_write_begin(&newfde->fde_seq); 2970 #endif 2971 memcpy(newfde, oldfde, fde_change_size); 2972 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps, true); 2973 #ifdef CAPABILITIES 2974 seq_write_end(&newfde->fde_seq); 2975 #endif 2976 break; 2977 case ENXIO: 2978 /* 2979 * Steal away the file pointer from dfd and stuff it into indx. 2980 */ 2981 newfde = &fdp->fd_ofiles[indx]; 2982 oldfde = &fdp->fd_ofiles[dfd]; 2983 #ifdef CAPABILITIES 2984 seq_write_begin(&newfde->fde_seq); 2985 #endif 2986 memcpy(newfde, oldfde, fde_change_size); 2987 oldfde->fde_file = NULL; 2988 fdunused(fdp, dfd); 2989 #ifdef CAPABILITIES 2990 seq_write_end(&newfde->fde_seq); 2991 #endif 2992 break; 2993 } 2994 FILEDESC_XUNLOCK(fdp); 2995 *indxp = indx; 2996 return (0); 2997 } 2998 2999 /* 3000 * This sysctl determines if we will allow a process to chroot(2) if it 3001 * has a directory open: 3002 * 0: disallowed for all processes. 3003 * 1: allowed for processes that were not already chroot(2)'ed. 3004 * 2: allowed for all processes. 3005 */ 3006 3007 static int chroot_allow_open_directories = 1; 3008 3009 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW, 3010 &chroot_allow_open_directories, 0, 3011 "Allow a process to chroot(2) if it has a directory open"); 3012 3013 /* 3014 * Helper function for raised chroot(2) security function: Refuse if 3015 * any filedescriptors are open directories. 3016 */ 3017 static int 3018 chroot_refuse_vdir_fds(struct filedesc *fdp) 3019 { 3020 struct vnode *vp; 3021 struct file *fp; 3022 int fd; 3023 3024 FILEDESC_LOCK_ASSERT(fdp); 3025 3026 for (fd = 0; fd <= fdp->fd_lastfile; fd++) { 3027 fp = fget_locked(fdp, fd); 3028 if (fp == NULL) 3029 continue; 3030 if (fp->f_type == DTYPE_VNODE) { 3031 vp = fp->f_vnode; 3032 if (vp->v_type == VDIR) 3033 return (EPERM); 3034 } 3035 } 3036 return (0); 3037 } 3038 3039 /* 3040 * Common routine for kern_chroot() and jail_attach(). The caller is 3041 * responsible for invoking priv_check() and mac_vnode_check_chroot() to 3042 * authorize this operation. 3043 */ 3044 int 3045 pwd_chroot(struct thread *td, struct vnode *vp) 3046 { 3047 struct filedesc *fdp; 3048 struct vnode *oldvp; 3049 int error; 3050 3051 fdp = td->td_proc->p_fd; 3052 FILEDESC_XLOCK(fdp); 3053 if (chroot_allow_open_directories == 0 || 3054 (chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) { 3055 error = chroot_refuse_vdir_fds(fdp); 3056 if (error != 0) { 3057 FILEDESC_XUNLOCK(fdp); 3058 return (error); 3059 } 3060 } 3061 oldvp = fdp->fd_rdir; 3062 vrefact(vp); 3063 fdp->fd_rdir = vp; 3064 if (fdp->fd_jdir == NULL) { 3065 vrefact(vp); 3066 fdp->fd_jdir = vp; 3067 } 3068 FILEDESC_XUNLOCK(fdp); 3069 vrele(oldvp); 3070 return (0); 3071 } 3072 3073 void 3074 pwd_chdir(struct thread *td, struct vnode *vp) 3075 { 3076 struct filedesc *fdp; 3077 struct vnode *oldvp; 3078 3079 fdp = td->td_proc->p_fd; 3080 FILEDESC_XLOCK(fdp); 3081 VNASSERT(vp->v_usecount > 0, vp, 3082 ("chdir to a vnode with zero usecount")); 3083 oldvp = fdp->fd_cdir; 3084 fdp->fd_cdir = vp; 3085 FILEDESC_XUNLOCK(fdp); 3086 vrele(oldvp); 3087 } 3088 3089 /* 3090 * Scan all active processes and prisons to see if any of them have a current 3091 * or root directory of `olddp'. If so, replace them with the new mount point. 3092 */ 3093 void 3094 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 3095 { 3096 struct filedesc *fdp; 3097 struct prison *pr; 3098 struct proc *p; 3099 int nrele; 3100 3101 if (vrefcnt(olddp) == 1) 3102 return; 3103 nrele = 0; 3104 sx_slock(&allproc_lock); 3105 FOREACH_PROC_IN_SYSTEM(p) { 3106 PROC_LOCK(p); 3107 fdp = fdhold(p); 3108 PROC_UNLOCK(p); 3109 if (fdp == NULL) 3110 continue; 3111 FILEDESC_XLOCK(fdp); 3112 if (fdp->fd_cdir == olddp) { 3113 vrefact(newdp); 3114 fdp->fd_cdir = newdp; 3115 nrele++; 3116 } 3117 if (fdp->fd_rdir == olddp) { 3118 vrefact(newdp); 3119 fdp->fd_rdir = newdp; 3120 nrele++; 3121 } 3122 if (fdp->fd_jdir == olddp) { 3123 vrefact(newdp); 3124 fdp->fd_jdir = newdp; 3125 nrele++; 3126 } 3127 FILEDESC_XUNLOCK(fdp); 3128 fddrop(fdp); 3129 } 3130 sx_sunlock(&allproc_lock); 3131 if (rootvnode == olddp) { 3132 vrefact(newdp); 3133 rootvnode = newdp; 3134 nrele++; 3135 } 3136 mtx_lock(&prison0.pr_mtx); 3137 if (prison0.pr_root == olddp) { 3138 vrefact(newdp); 3139 prison0.pr_root = newdp; 3140 nrele++; 3141 } 3142 mtx_unlock(&prison0.pr_mtx); 3143 sx_slock(&allprison_lock); 3144 TAILQ_FOREACH(pr, &allprison, pr_list) { 3145 mtx_lock(&pr->pr_mtx); 3146 if (pr->pr_root == olddp) { 3147 vrefact(newdp); 3148 pr->pr_root = newdp; 3149 nrele++; 3150 } 3151 mtx_unlock(&pr->pr_mtx); 3152 } 3153 sx_sunlock(&allprison_lock); 3154 while (nrele--) 3155 vrele(olddp); 3156 } 3157 3158 struct filedesc_to_leader * 3159 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 3160 { 3161 struct filedesc_to_leader *fdtol; 3162 3163 fdtol = malloc(sizeof(struct filedesc_to_leader), 3164 M_FILEDESC_TO_LEADER, M_WAITOK); 3165 fdtol->fdl_refcount = 1; 3166 fdtol->fdl_holdcount = 0; 3167 fdtol->fdl_wakeup = 0; 3168 fdtol->fdl_leader = leader; 3169 if (old != NULL) { 3170 FILEDESC_XLOCK(fdp); 3171 fdtol->fdl_next = old->fdl_next; 3172 fdtol->fdl_prev = old; 3173 old->fdl_next = fdtol; 3174 fdtol->fdl_next->fdl_prev = fdtol; 3175 FILEDESC_XUNLOCK(fdp); 3176 } else { 3177 fdtol->fdl_next = fdtol; 3178 fdtol->fdl_prev = fdtol; 3179 } 3180 return (fdtol); 3181 } 3182 3183 static int 3184 sysctl_kern_proc_nfds(SYSCTL_HANDLER_ARGS) 3185 { 3186 struct filedesc *fdp; 3187 int i, count, slots; 3188 3189 if (*(int *)arg1 != 0) 3190 return (EINVAL); 3191 3192 fdp = curproc->p_fd; 3193 count = 0; 3194 FILEDESC_SLOCK(fdp); 3195 slots = NDSLOTS(fdp->fd_lastfile + 1); 3196 for (i = 0; i < slots; i++) 3197 count += bitcountl(fdp->fd_map[i]); 3198 FILEDESC_SUNLOCK(fdp); 3199 3200 return (SYSCTL_OUT(req, &count, sizeof(count))); 3201 } 3202 3203 static SYSCTL_NODE(_kern_proc, KERN_PROC_NFDS, nfds, 3204 CTLFLAG_RD|CTLFLAG_CAPRD|CTLFLAG_MPSAFE, sysctl_kern_proc_nfds, 3205 "Number of open file descriptors"); 3206 3207 /* 3208 * Get file structures globally. 3209 */ 3210 static int 3211 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 3212 { 3213 struct xfile xf; 3214 struct filedesc *fdp; 3215 struct file *fp; 3216 struct proc *p; 3217 int error, n; 3218 3219 error = sysctl_wire_old_buffer(req, 0); 3220 if (error != 0) 3221 return (error); 3222 if (req->oldptr == NULL) { 3223 n = 0; 3224 sx_slock(&allproc_lock); 3225 FOREACH_PROC_IN_SYSTEM(p) { 3226 PROC_LOCK(p); 3227 if (p->p_state == PRS_NEW) { 3228 PROC_UNLOCK(p); 3229 continue; 3230 } 3231 fdp = fdhold(p); 3232 PROC_UNLOCK(p); 3233 if (fdp == NULL) 3234 continue; 3235 /* overestimates sparse tables. */ 3236 if (fdp->fd_lastfile > 0) 3237 n += fdp->fd_lastfile; 3238 fddrop(fdp); 3239 } 3240 sx_sunlock(&allproc_lock); 3241 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 3242 } 3243 error = 0; 3244 bzero(&xf, sizeof(xf)); 3245 xf.xf_size = sizeof(xf); 3246 sx_slock(&allproc_lock); 3247 FOREACH_PROC_IN_SYSTEM(p) { 3248 PROC_LOCK(p); 3249 if (p->p_state == PRS_NEW) { 3250 PROC_UNLOCK(p); 3251 continue; 3252 } 3253 if (p_cansee(req->td, p) != 0) { 3254 PROC_UNLOCK(p); 3255 continue; 3256 } 3257 xf.xf_pid = p->p_pid; 3258 xf.xf_uid = p->p_ucred->cr_uid; 3259 fdp = fdhold(p); 3260 PROC_UNLOCK(p); 3261 if (fdp == NULL) 3262 continue; 3263 FILEDESC_SLOCK(fdp); 3264 for (n = 0; fdp->fd_refcnt > 0 && n <= fdp->fd_lastfile; ++n) { 3265 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3266 continue; 3267 xf.xf_fd = n; 3268 xf.xf_file = fp; 3269 xf.xf_data = fp->f_data; 3270 xf.xf_vnode = fp->f_vnode; 3271 xf.xf_type = fp->f_type; 3272 xf.xf_count = fp->f_count; 3273 xf.xf_msgcount = 0; 3274 xf.xf_offset = foffset_get(fp); 3275 xf.xf_flag = fp->f_flag; 3276 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 3277 if (error) 3278 break; 3279 } 3280 FILEDESC_SUNLOCK(fdp); 3281 fddrop(fdp); 3282 if (error) 3283 break; 3284 } 3285 sx_sunlock(&allproc_lock); 3286 return (error); 3287 } 3288 3289 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 3290 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 3291 3292 #ifdef KINFO_FILE_SIZE 3293 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3294 #endif 3295 3296 static int 3297 xlate_fflags(int fflags) 3298 { 3299 static const struct { 3300 int fflag; 3301 int kf_fflag; 3302 } fflags_table[] = { 3303 { FAPPEND, KF_FLAG_APPEND }, 3304 { FASYNC, KF_FLAG_ASYNC }, 3305 { FFSYNC, KF_FLAG_FSYNC }, 3306 { FHASLOCK, KF_FLAG_HASLOCK }, 3307 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3308 { FREAD, KF_FLAG_READ }, 3309 { FWRITE, KF_FLAG_WRITE }, 3310 { O_CREAT, KF_FLAG_CREAT }, 3311 { O_DIRECT, KF_FLAG_DIRECT }, 3312 { O_EXCL, KF_FLAG_EXCL }, 3313 { O_EXEC, KF_FLAG_EXEC }, 3314 { O_EXLOCK, KF_FLAG_EXLOCK }, 3315 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3316 { O_SHLOCK, KF_FLAG_SHLOCK }, 3317 { O_TRUNC, KF_FLAG_TRUNC } 3318 }; 3319 unsigned int i; 3320 int kflags; 3321 3322 kflags = 0; 3323 for (i = 0; i < nitems(fflags_table); i++) 3324 if (fflags & fflags_table[i].fflag) 3325 kflags |= fflags_table[i].kf_fflag; 3326 return (kflags); 3327 } 3328 3329 /* Trim unused data from kf_path by truncating the structure size. */ 3330 static void 3331 pack_kinfo(struct kinfo_file *kif) 3332 { 3333 3334 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3335 strlen(kif->kf_path) + 1; 3336 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3337 } 3338 3339 static void 3340 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp, 3341 struct kinfo_file *kif, struct filedesc *fdp, int flags) 3342 { 3343 int error; 3344 3345 bzero(kif, sizeof(*kif)); 3346 3347 /* Set a default type to allow for empty fill_kinfo() methods. */ 3348 kif->kf_type = KF_TYPE_UNKNOWN; 3349 kif->kf_flags = xlate_fflags(fp->f_flag); 3350 if (rightsp != NULL) 3351 kif->kf_cap_rights = *rightsp; 3352 else 3353 cap_rights_init(&kif->kf_cap_rights); 3354 kif->kf_fd = fd; 3355 kif->kf_ref_count = fp->f_count; 3356 kif->kf_offset = foffset_get(fp); 3357 3358 /* 3359 * This may drop the filedesc lock, so the 'fp' cannot be 3360 * accessed after this call. 3361 */ 3362 error = fo_fill_kinfo(fp, kif, fdp); 3363 if (error == 0) 3364 kif->kf_status |= KF_ATTR_VALID; 3365 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 3366 pack_kinfo(kif); 3367 else 3368 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 3369 } 3370 3371 static void 3372 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags, 3373 struct kinfo_file *kif, int flags) 3374 { 3375 int error; 3376 3377 bzero(kif, sizeof(*kif)); 3378 3379 kif->kf_type = KF_TYPE_VNODE; 3380 error = vn_fill_kinfo_vnode(vp, kif); 3381 if (error == 0) 3382 kif->kf_status |= KF_ATTR_VALID; 3383 kif->kf_flags = xlate_fflags(fflags); 3384 cap_rights_init(&kif->kf_cap_rights); 3385 kif->kf_fd = fd; 3386 kif->kf_ref_count = -1; 3387 kif->kf_offset = -1; 3388 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 3389 pack_kinfo(kif); 3390 else 3391 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 3392 vrele(vp); 3393 } 3394 3395 struct export_fd_buf { 3396 struct filedesc *fdp; 3397 struct sbuf *sb; 3398 ssize_t remainder; 3399 struct kinfo_file kif; 3400 int flags; 3401 }; 3402 3403 static int 3404 export_kinfo_to_sb(struct export_fd_buf *efbuf) 3405 { 3406 struct kinfo_file *kif; 3407 3408 kif = &efbuf->kif; 3409 if (efbuf->remainder != -1) { 3410 if (efbuf->remainder < kif->kf_structsize) { 3411 /* Terminate export. */ 3412 efbuf->remainder = 0; 3413 return (0); 3414 } 3415 efbuf->remainder -= kif->kf_structsize; 3416 } 3417 return (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) == 0 ? 0 : ENOMEM); 3418 } 3419 3420 static int 3421 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp, 3422 struct export_fd_buf *efbuf) 3423 { 3424 int error; 3425 3426 if (efbuf->remainder == 0) 3427 return (0); 3428 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp, 3429 efbuf->flags); 3430 FILEDESC_SUNLOCK(efbuf->fdp); 3431 error = export_kinfo_to_sb(efbuf); 3432 FILEDESC_SLOCK(efbuf->fdp); 3433 return (error); 3434 } 3435 3436 static int 3437 export_vnode_to_sb(struct vnode *vp, int fd, int fflags, 3438 struct export_fd_buf *efbuf) 3439 { 3440 int error; 3441 3442 if (efbuf->remainder == 0) 3443 return (0); 3444 if (efbuf->fdp != NULL) 3445 FILEDESC_SUNLOCK(efbuf->fdp); 3446 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif, efbuf->flags); 3447 error = export_kinfo_to_sb(efbuf); 3448 if (efbuf->fdp != NULL) 3449 FILEDESC_SLOCK(efbuf->fdp); 3450 return (error); 3451 } 3452 3453 /* 3454 * Store a process file descriptor information to sbuf. 3455 * 3456 * Takes a locked proc as argument, and returns with the proc unlocked. 3457 */ 3458 int 3459 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen, 3460 int flags) 3461 { 3462 struct file *fp; 3463 struct filedesc *fdp; 3464 struct export_fd_buf *efbuf; 3465 struct vnode *cttyvp, *textvp, *tracevp; 3466 int error, i; 3467 cap_rights_t rights; 3468 3469 PROC_LOCK_ASSERT(p, MA_OWNED); 3470 3471 /* ktrace vnode */ 3472 tracevp = p->p_tracevp; 3473 if (tracevp != NULL) 3474 vrefact(tracevp); 3475 /* text vnode */ 3476 textvp = p->p_textvp; 3477 if (textvp != NULL) 3478 vrefact(textvp); 3479 /* Controlling tty. */ 3480 cttyvp = NULL; 3481 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3482 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3483 if (cttyvp != NULL) 3484 vrefact(cttyvp); 3485 } 3486 fdp = fdhold(p); 3487 PROC_UNLOCK(p); 3488 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3489 efbuf->fdp = NULL; 3490 efbuf->sb = sb; 3491 efbuf->remainder = maxlen; 3492 efbuf->flags = flags; 3493 if (tracevp != NULL) 3494 export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE, FREAD | FWRITE, 3495 efbuf); 3496 if (textvp != NULL) 3497 export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD, efbuf); 3498 if (cttyvp != NULL) 3499 export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY, FREAD | FWRITE, 3500 efbuf); 3501 error = 0; 3502 if (fdp == NULL) 3503 goto fail; 3504 efbuf->fdp = fdp; 3505 FILEDESC_SLOCK(fdp); 3506 /* working directory */ 3507 if (fdp->fd_cdir != NULL) { 3508 vrefact(fdp->fd_cdir); 3509 export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD, FREAD, efbuf); 3510 } 3511 /* root directory */ 3512 if (fdp->fd_rdir != NULL) { 3513 vrefact(fdp->fd_rdir); 3514 export_vnode_to_sb(fdp->fd_rdir, KF_FD_TYPE_ROOT, FREAD, efbuf); 3515 } 3516 /* jail directory */ 3517 if (fdp->fd_jdir != NULL) { 3518 vrefact(fdp->fd_jdir); 3519 export_vnode_to_sb(fdp->fd_jdir, KF_FD_TYPE_JAIL, FREAD, efbuf); 3520 } 3521 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3522 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3523 continue; 3524 #ifdef CAPABILITIES 3525 rights = *cap_rights(fdp, i); 3526 #else /* !CAPABILITIES */ 3527 cap_rights_init(&rights); 3528 #endif 3529 /* 3530 * Create sysctl entry. It is OK to drop the filedesc 3531 * lock inside of export_file_to_sb() as we will 3532 * re-validate and re-evaluate its properties when the 3533 * loop continues. 3534 */ 3535 error = export_file_to_sb(fp, i, &rights, efbuf); 3536 if (error != 0 || efbuf->remainder == 0) 3537 break; 3538 } 3539 FILEDESC_SUNLOCK(fdp); 3540 fddrop(fdp); 3541 fail: 3542 free(efbuf, M_TEMP); 3543 return (error); 3544 } 3545 3546 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3547 3548 /* 3549 * Get per-process file descriptors for use by procstat(1), et al. 3550 */ 3551 static int 3552 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3553 { 3554 struct sbuf sb; 3555 struct proc *p; 3556 ssize_t maxlen; 3557 int error, error2, *name; 3558 3559 name = (int *)arg1; 3560 3561 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3562 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 3563 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3564 if (error != 0) { 3565 sbuf_delete(&sb); 3566 return (error); 3567 } 3568 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3569 error = kern_proc_filedesc_out(p, &sb, maxlen, 3570 KERN_FILEDESC_PACK_KINFO); 3571 error2 = sbuf_finish(&sb); 3572 sbuf_delete(&sb); 3573 return (error != 0 ? error : error2); 3574 } 3575 3576 #ifdef KINFO_OFILE_SIZE 3577 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 3578 #endif 3579 3580 #ifdef COMPAT_FREEBSD7 3581 static void 3582 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif) 3583 { 3584 3585 okif->kf_structsize = sizeof(*okif); 3586 okif->kf_type = kif->kf_type; 3587 okif->kf_fd = kif->kf_fd; 3588 okif->kf_ref_count = kif->kf_ref_count; 3589 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE | 3590 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK | 3591 KF_FLAG_DIRECT | KF_FLAG_HASLOCK); 3592 okif->kf_offset = kif->kf_offset; 3593 okif->kf_vnode_type = kif->kf_vnode_type; 3594 okif->kf_sock_domain = kif->kf_sock_domain; 3595 okif->kf_sock_type = kif->kf_sock_type; 3596 okif->kf_sock_protocol = kif->kf_sock_protocol; 3597 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path)); 3598 okif->kf_sa_local = kif->kf_sa_local; 3599 okif->kf_sa_peer = kif->kf_sa_peer; 3600 } 3601 3602 static int 3603 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif, 3604 struct kinfo_ofile *okif, struct filedesc *fdp, struct sysctl_req *req) 3605 { 3606 int error; 3607 3608 vrefact(vp); 3609 FILEDESC_SUNLOCK(fdp); 3610 export_vnode_to_kinfo(vp, type, 0, kif, KERN_FILEDESC_PACK_KINFO); 3611 kinfo_to_okinfo(kif, okif); 3612 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 3613 FILEDESC_SLOCK(fdp); 3614 return (error); 3615 } 3616 3617 /* 3618 * Get per-process file descriptors for use by procstat(1), et al. 3619 */ 3620 static int 3621 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3622 { 3623 struct kinfo_ofile *okif; 3624 struct kinfo_file *kif; 3625 struct filedesc *fdp; 3626 int error, i, *name; 3627 struct file *fp; 3628 struct proc *p; 3629 3630 name = (int *)arg1; 3631 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3632 if (error != 0) 3633 return (error); 3634 fdp = fdhold(p); 3635 PROC_UNLOCK(p); 3636 if (fdp == NULL) 3637 return (ENOENT); 3638 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3639 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK); 3640 FILEDESC_SLOCK(fdp); 3641 if (fdp->fd_cdir != NULL) 3642 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3643 okif, fdp, req); 3644 if (fdp->fd_rdir != NULL) 3645 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3646 okif, fdp, req); 3647 if (fdp->fd_jdir != NULL) 3648 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3649 okif, fdp, req); 3650 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3651 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3652 continue; 3653 export_file_to_kinfo(fp, i, NULL, kif, fdp, 3654 KERN_FILEDESC_PACK_KINFO); 3655 FILEDESC_SUNLOCK(fdp); 3656 kinfo_to_okinfo(kif, okif); 3657 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 3658 FILEDESC_SLOCK(fdp); 3659 if (error) 3660 break; 3661 } 3662 FILEDESC_SUNLOCK(fdp); 3663 fddrop(fdp); 3664 free(kif, M_TEMP); 3665 free(okif, M_TEMP); 3666 return (0); 3667 } 3668 3669 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 3670 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 3671 "Process ofiledesc entries"); 3672 #endif /* COMPAT_FREEBSD7 */ 3673 3674 int 3675 vntype_to_kinfo(int vtype) 3676 { 3677 struct { 3678 int vtype; 3679 int kf_vtype; 3680 } vtypes_table[] = { 3681 { VBAD, KF_VTYPE_VBAD }, 3682 { VBLK, KF_VTYPE_VBLK }, 3683 { VCHR, KF_VTYPE_VCHR }, 3684 { VDIR, KF_VTYPE_VDIR }, 3685 { VFIFO, KF_VTYPE_VFIFO }, 3686 { VLNK, KF_VTYPE_VLNK }, 3687 { VNON, KF_VTYPE_VNON }, 3688 { VREG, KF_VTYPE_VREG }, 3689 { VSOCK, KF_VTYPE_VSOCK } 3690 }; 3691 unsigned int i; 3692 3693 /* 3694 * Perform vtype translation. 3695 */ 3696 for (i = 0; i < nitems(vtypes_table); i++) 3697 if (vtypes_table[i].vtype == vtype) 3698 return (vtypes_table[i].kf_vtype); 3699 3700 return (KF_VTYPE_UNKNOWN); 3701 } 3702 3703 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 3704 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 3705 "Process filedesc entries"); 3706 3707 /* 3708 * Store a process current working directory information to sbuf. 3709 * 3710 * Takes a locked proc as argument, and returns with the proc unlocked. 3711 */ 3712 int 3713 kern_proc_cwd_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3714 { 3715 struct filedesc *fdp; 3716 struct export_fd_buf *efbuf; 3717 int error; 3718 3719 PROC_LOCK_ASSERT(p, MA_OWNED); 3720 3721 fdp = fdhold(p); 3722 PROC_UNLOCK(p); 3723 if (fdp == NULL) 3724 return (EINVAL); 3725 3726 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3727 efbuf->fdp = fdp; 3728 efbuf->sb = sb; 3729 efbuf->remainder = maxlen; 3730 3731 FILEDESC_SLOCK(fdp); 3732 if (fdp->fd_cdir == NULL) 3733 error = EINVAL; 3734 else { 3735 vrefact(fdp->fd_cdir); 3736 error = export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD, 3737 FREAD, efbuf); 3738 } 3739 FILEDESC_SUNLOCK(fdp); 3740 fddrop(fdp); 3741 free(efbuf, M_TEMP); 3742 return (error); 3743 } 3744 3745 /* 3746 * Get per-process current working directory. 3747 */ 3748 static int 3749 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS) 3750 { 3751 struct sbuf sb; 3752 struct proc *p; 3753 ssize_t maxlen; 3754 int error, error2, *name; 3755 3756 name = (int *)arg1; 3757 3758 sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file), req); 3759 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 3760 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3761 if (error != 0) { 3762 sbuf_delete(&sb); 3763 return (error); 3764 } 3765 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3766 error = kern_proc_cwd_out(p, &sb, maxlen); 3767 error2 = sbuf_finish(&sb); 3768 sbuf_delete(&sb); 3769 return (error != 0 ? error : error2); 3770 } 3771 3772 static SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD|CTLFLAG_MPSAFE, 3773 sysctl_kern_proc_cwd, "Process current working directory"); 3774 3775 #ifdef DDB 3776 /* 3777 * For the purposes of debugging, generate a human-readable string for the 3778 * file type. 3779 */ 3780 static const char * 3781 file_type_to_name(short type) 3782 { 3783 3784 switch (type) { 3785 case 0: 3786 return ("zero"); 3787 case DTYPE_VNODE: 3788 return ("vnod"); 3789 case DTYPE_SOCKET: 3790 return ("sock"); 3791 case DTYPE_PIPE: 3792 return ("pipe"); 3793 case DTYPE_FIFO: 3794 return ("fifo"); 3795 case DTYPE_KQUEUE: 3796 return ("kque"); 3797 case DTYPE_CRYPTO: 3798 return ("crpt"); 3799 case DTYPE_MQUEUE: 3800 return ("mque"); 3801 case DTYPE_SHM: 3802 return ("shm"); 3803 case DTYPE_SEM: 3804 return ("ksem"); 3805 default: 3806 return ("unkn"); 3807 } 3808 } 3809 3810 /* 3811 * For the purposes of debugging, identify a process (if any, perhaps one of 3812 * many) that references the passed file in its file descriptor array. Return 3813 * NULL if none. 3814 */ 3815 static struct proc * 3816 file_to_first_proc(struct file *fp) 3817 { 3818 struct filedesc *fdp; 3819 struct proc *p; 3820 int n; 3821 3822 FOREACH_PROC_IN_SYSTEM(p) { 3823 if (p->p_state == PRS_NEW) 3824 continue; 3825 fdp = p->p_fd; 3826 if (fdp == NULL) 3827 continue; 3828 for (n = 0; n <= fdp->fd_lastfile; n++) { 3829 if (fp == fdp->fd_ofiles[n].fde_file) 3830 return (p); 3831 } 3832 } 3833 return (NULL); 3834 } 3835 3836 static void 3837 db_print_file(struct file *fp, int header) 3838 { 3839 struct proc *p; 3840 3841 if (header) 3842 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3843 "File", "Type", "Data", "Flag", "GCFl", "Count", 3844 "MCount", "Vnode", "FPID", "FCmd"); 3845 p = file_to_first_proc(fp); 3846 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3847 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3848 0, fp->f_count, 0, fp->f_vnode, 3849 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3850 } 3851 3852 DB_SHOW_COMMAND(file, db_show_file) 3853 { 3854 struct file *fp; 3855 3856 if (!have_addr) { 3857 db_printf("usage: show file <addr>\n"); 3858 return; 3859 } 3860 fp = (struct file *)addr; 3861 db_print_file(fp, 1); 3862 } 3863 3864 DB_SHOW_COMMAND(files, db_show_files) 3865 { 3866 struct filedesc *fdp; 3867 struct file *fp; 3868 struct proc *p; 3869 int header; 3870 int n; 3871 3872 header = 1; 3873 FOREACH_PROC_IN_SYSTEM(p) { 3874 if (p->p_state == PRS_NEW) 3875 continue; 3876 if ((fdp = p->p_fd) == NULL) 3877 continue; 3878 for (n = 0; n <= fdp->fd_lastfile; ++n) { 3879 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3880 continue; 3881 db_print_file(fp, header); 3882 header = 0; 3883 } 3884 } 3885 } 3886 #endif 3887 3888 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3889 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3890 3891 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3892 &maxfiles, 0, "Maximum number of files"); 3893 3894 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3895 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3896 3897 /* ARGSUSED*/ 3898 static void 3899 filelistinit(void *dummy) 3900 { 3901 3902 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3903 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3904 filedesc0_zone = uma_zcreate("filedesc0", sizeof(struct filedesc0), 3905 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 3906 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3907 } 3908 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3909 3910 /*-------------------------------------------------------------------*/ 3911 3912 static int 3913 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3914 int flags, struct thread *td) 3915 { 3916 3917 return (EBADF); 3918 } 3919 3920 static int 3921 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3922 struct thread *td) 3923 { 3924 3925 return (EINVAL); 3926 } 3927 3928 static int 3929 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3930 struct thread *td) 3931 { 3932 3933 return (EBADF); 3934 } 3935 3936 static int 3937 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3938 struct thread *td) 3939 { 3940 3941 return (0); 3942 } 3943 3944 static int 3945 badfo_kqfilter(struct file *fp, struct knote *kn) 3946 { 3947 3948 return (EBADF); 3949 } 3950 3951 static int 3952 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3953 struct thread *td) 3954 { 3955 3956 return (EBADF); 3957 } 3958 3959 static int 3960 badfo_close(struct file *fp, struct thread *td) 3961 { 3962 3963 return (0); 3964 } 3965 3966 static int 3967 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3968 struct thread *td) 3969 { 3970 3971 return (EBADF); 3972 } 3973 3974 static int 3975 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3976 struct thread *td) 3977 { 3978 3979 return (EBADF); 3980 } 3981 3982 static int 3983 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3984 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3985 struct thread *td) 3986 { 3987 3988 return (EBADF); 3989 } 3990 3991 static int 3992 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp) 3993 { 3994 3995 return (0); 3996 } 3997 3998 struct fileops badfileops = { 3999 .fo_read = badfo_readwrite, 4000 .fo_write = badfo_readwrite, 4001 .fo_truncate = badfo_truncate, 4002 .fo_ioctl = badfo_ioctl, 4003 .fo_poll = badfo_poll, 4004 .fo_kqfilter = badfo_kqfilter, 4005 .fo_stat = badfo_stat, 4006 .fo_close = badfo_close, 4007 .fo_chmod = badfo_chmod, 4008 .fo_chown = badfo_chown, 4009 .fo_sendfile = badfo_sendfile, 4010 .fo_fill_kinfo = badfo_fill_kinfo, 4011 }; 4012 4013 int 4014 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred, 4015 int flags, struct thread *td) 4016 { 4017 4018 return (EOPNOTSUPP); 4019 } 4020 4021 int 4022 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 4023 struct thread *td) 4024 { 4025 4026 return (EINVAL); 4027 } 4028 4029 int 4030 invfo_ioctl(struct file *fp, u_long com, void *data, 4031 struct ucred *active_cred, struct thread *td) 4032 { 4033 4034 return (ENOTTY); 4035 } 4036 4037 int 4038 invfo_poll(struct file *fp, int events, struct ucred *active_cred, 4039 struct thread *td) 4040 { 4041 4042 return (poll_no_poll(events)); 4043 } 4044 4045 int 4046 invfo_kqfilter(struct file *fp, struct knote *kn) 4047 { 4048 4049 return (EINVAL); 4050 } 4051 4052 int 4053 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 4054 struct thread *td) 4055 { 4056 4057 return (EINVAL); 4058 } 4059 4060 int 4061 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4062 struct thread *td) 4063 { 4064 4065 return (EINVAL); 4066 } 4067 4068 int 4069 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4070 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4071 struct thread *td) 4072 { 4073 4074 return (EINVAL); 4075 } 4076 4077 /*-------------------------------------------------------------------*/ 4078 4079 /* 4080 * File Descriptor pseudo-device driver (/dev/fd/). 4081 * 4082 * Opening minor device N dup()s the file (if any) connected to file 4083 * descriptor N belonging to the calling process. Note that this driver 4084 * consists of only the ``open()'' routine, because all subsequent 4085 * references to this file will be direct to the other driver. 4086 * 4087 * XXX: we could give this one a cloning event handler if necessary. 4088 */ 4089 4090 /* ARGSUSED */ 4091 static int 4092 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 4093 { 4094 4095 /* 4096 * XXX Kludge: set curthread->td_dupfd to contain the value of the 4097 * the file descriptor being sought for duplication. The error 4098 * return ensures that the vnode for this device will be released 4099 * by vn_open. Open will detect this special error and take the 4100 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 4101 * will simply report the error. 4102 */ 4103 td->td_dupfd = dev2unit(dev); 4104 return (ENODEV); 4105 } 4106 4107 static struct cdevsw fildesc_cdevsw = { 4108 .d_version = D_VERSION, 4109 .d_open = fdopen, 4110 .d_name = "FD", 4111 }; 4112 4113 static void 4114 fildesc_drvinit(void *unused) 4115 { 4116 struct cdev *dev; 4117 4118 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4119 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4120 make_dev_alias(dev, "stdin"); 4121 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4122 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4123 make_dev_alias(dev, "stdout"); 4124 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4125 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4126 make_dev_alias(dev, "stderr"); 4127 } 4128 4129 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4130