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 * 4. 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/socketvar.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 uma_zone_t file_zone; 101 102 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 103 struct thread *td, int holdleaders); 104 static int fd_first_free(struct filedesc *fdp, int low, int size); 105 static int fd_last_used(struct filedesc *fdp, int size); 106 static void fdgrowtable(struct filedesc *fdp, int nfd); 107 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 108 static void fdunused(struct filedesc *fdp, int fd); 109 static void fdused(struct filedesc *fdp, int fd); 110 static int getmaxfd(struct proc *p); 111 112 /* 113 * Each process has: 114 * 115 * - An array of open file descriptors (fd_ofiles) 116 * - An array of file flags (fd_ofileflags) 117 * - A bitmap recording which descriptors are in use (fd_map) 118 * 119 * A process starts out with NDFILE descriptors. The value of NDFILE has 120 * been selected based the historical limit of 20 open files, and an 121 * assumption that the majority of processes, especially short-lived 122 * processes like shells, will never need more. 123 * 124 * If this initial allocation is exhausted, a larger descriptor table and 125 * map are allocated dynamically, and the pointers in the process's struct 126 * filedesc are updated to point to those. This is repeated every time 127 * the process runs out of file descriptors (provided it hasn't hit its 128 * resource limit). 129 * 130 * Since threads may hold references to individual descriptor table 131 * entries, the tables are never freed. Instead, they are placed on a 132 * linked list and freed only when the struct filedesc is released. 133 */ 134 #define NDFILE 20 135 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 136 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 137 #define NDSLOT(x) ((x) / NDENTRIES) 138 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 139 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 140 141 /* 142 * SLIST entry used to keep track of ofiles which must be reclaimed when 143 * the process exits. 144 */ 145 struct freetable { 146 struct filedescent *ft_table; 147 SLIST_ENTRY(freetable) ft_next; 148 }; 149 150 /* 151 * Initial allocation: a filedesc structure + the head of SLIST used to 152 * keep track of old ofiles + enough space for NDFILE descriptors. 153 */ 154 struct filedesc0 { 155 struct filedesc fd_fd; 156 SLIST_HEAD(, freetable) fd_free; 157 struct filedescent fd_dfiles[NDFILE]; 158 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 159 }; 160 161 /* 162 * Descriptor management. 163 */ 164 volatile int openfiles; /* actual number of open files */ 165 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 166 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 167 168 /* A mutex to protect the association between a proc and filedesc. */ 169 static struct mtx fdesc_mtx; 170 171 /* 172 * If low >= size, just return low. Otherwise find the first zero bit in the 173 * given bitmap, starting at low and not exceeding size - 1. Return size if 174 * not found. 175 */ 176 static int 177 fd_first_free(struct filedesc *fdp, int low, int size) 178 { 179 NDSLOTTYPE *map = fdp->fd_map; 180 NDSLOTTYPE mask; 181 int off, maxoff; 182 183 if (low >= size) 184 return (low); 185 186 off = NDSLOT(low); 187 if (low % NDENTRIES) { 188 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 189 if ((mask &= ~map[off]) != 0UL) 190 return (off * NDENTRIES + ffsl(mask) - 1); 191 ++off; 192 } 193 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 194 if (map[off] != ~0UL) 195 return (off * NDENTRIES + ffsl(~map[off]) - 1); 196 return (size); 197 } 198 199 /* 200 * Find the highest non-zero bit in the given bitmap, starting at 0 and 201 * not exceeding size - 1. Return -1 if not found. 202 */ 203 static int 204 fd_last_used(struct filedesc *fdp, int size) 205 { 206 NDSLOTTYPE *map = fdp->fd_map; 207 NDSLOTTYPE mask; 208 int off, minoff; 209 210 off = NDSLOT(size); 211 if (size % NDENTRIES) { 212 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 213 if ((mask &= map[off]) != 0) 214 return (off * NDENTRIES + flsl(mask) - 1); 215 --off; 216 } 217 for (minoff = NDSLOT(0); off >= minoff; --off) 218 if (map[off] != 0) 219 return (off * NDENTRIES + flsl(map[off]) - 1); 220 return (-1); 221 } 222 223 static int 224 fdisused(struct filedesc *fdp, int fd) 225 { 226 227 FILEDESC_LOCK_ASSERT(fdp); 228 229 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 230 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 231 232 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 233 } 234 235 /* 236 * Mark a file descriptor as used. 237 */ 238 static void 239 fdused(struct filedesc *fdp, int fd) 240 { 241 242 FILEDESC_XLOCK_ASSERT(fdp); 243 244 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 245 246 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 247 if (fd > fdp->fd_lastfile) 248 fdp->fd_lastfile = fd; 249 if (fd == fdp->fd_freefile) 250 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 251 } 252 253 /* 254 * Mark a file descriptor as unused. 255 */ 256 static void 257 fdunused(struct filedesc *fdp, int fd) 258 { 259 260 FILEDESC_XLOCK_ASSERT(fdp); 261 262 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 263 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 264 ("fd=%d is still in use", fd)); 265 266 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 267 if (fd < fdp->fd_freefile) 268 fdp->fd_freefile = fd; 269 if (fd == fdp->fd_lastfile) 270 fdp->fd_lastfile = fd_last_used(fdp, fd); 271 } 272 273 /* 274 * Free a file descriptor. 275 * 276 * Avoid some work if fdp is about to be destroyed. 277 */ 278 static inline void 279 _fdfree(struct filedesc *fdp, int fd, int last) 280 { 281 struct filedescent *fde; 282 283 fde = &fdp->fd_ofiles[fd]; 284 filecaps_free(&fde->fde_caps); 285 if (last) 286 return; 287 bzero(fde, sizeof(*fde)); 288 fdunused(fdp, fd); 289 } 290 291 static inline void 292 fdfree(struct filedesc *fdp, int fd) 293 { 294 295 _fdfree(fdp, fd, 0); 296 } 297 298 static inline void 299 fdfree_last(struct filedesc *fdp, int fd) 300 { 301 302 _fdfree(fdp, fd, 1); 303 } 304 305 /* 306 * System calls on descriptors. 307 */ 308 #ifndef _SYS_SYSPROTO_H_ 309 struct getdtablesize_args { 310 int dummy; 311 }; 312 #endif 313 /* ARGSUSED */ 314 int 315 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 316 { 317 struct proc *p = td->td_proc; 318 uint64_t lim; 319 320 PROC_LOCK(p); 321 td->td_retval[0] = 322 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 323 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 324 PROC_UNLOCK(p); 325 if (lim < td->td_retval[0]) 326 td->td_retval[0] = lim; 327 return (0); 328 } 329 330 /* 331 * Duplicate a file descriptor to a particular value. 332 * 333 * Note: keep in mind that a potential race condition exists when closing 334 * descriptors from a shared descriptor table (via rfork). 335 */ 336 #ifndef _SYS_SYSPROTO_H_ 337 struct dup2_args { 338 u_int from; 339 u_int to; 340 }; 341 #endif 342 /* ARGSUSED */ 343 int 344 sys_dup2(struct thread *td, struct dup2_args *uap) 345 { 346 347 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 348 td->td_retval)); 349 } 350 351 /* 352 * Duplicate a file descriptor. 353 */ 354 #ifndef _SYS_SYSPROTO_H_ 355 struct dup_args { 356 u_int fd; 357 }; 358 #endif 359 /* ARGSUSED */ 360 int 361 sys_dup(struct thread *td, struct dup_args *uap) 362 { 363 364 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 365 } 366 367 /* 368 * The file control system call. 369 */ 370 #ifndef _SYS_SYSPROTO_H_ 371 struct fcntl_args { 372 int fd; 373 int cmd; 374 long arg; 375 }; 376 #endif 377 /* ARGSUSED */ 378 int 379 sys_fcntl(struct thread *td, struct fcntl_args *uap) 380 { 381 struct flock fl; 382 struct __oflock ofl; 383 intptr_t arg; 384 int error; 385 int cmd; 386 387 error = 0; 388 cmd = uap->cmd; 389 switch (uap->cmd) { 390 case F_OGETLK: 391 case F_OSETLK: 392 case F_OSETLKW: 393 /* 394 * Convert old flock structure to new. 395 */ 396 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 397 fl.l_start = ofl.l_start; 398 fl.l_len = ofl.l_len; 399 fl.l_pid = ofl.l_pid; 400 fl.l_type = ofl.l_type; 401 fl.l_whence = ofl.l_whence; 402 fl.l_sysid = 0; 403 404 switch (uap->cmd) { 405 case F_OGETLK: 406 cmd = F_GETLK; 407 break; 408 case F_OSETLK: 409 cmd = F_SETLK; 410 break; 411 case F_OSETLKW: 412 cmd = F_SETLKW; 413 break; 414 } 415 arg = (intptr_t)&fl; 416 break; 417 case F_GETLK: 418 case F_SETLK: 419 case F_SETLKW: 420 case F_SETLK_REMOTE: 421 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 422 arg = (intptr_t)&fl; 423 break; 424 default: 425 arg = uap->arg; 426 break; 427 } 428 if (error) 429 return (error); 430 error = kern_fcntl(td, uap->fd, cmd, arg); 431 if (error) 432 return (error); 433 if (uap->cmd == F_OGETLK) { 434 ofl.l_start = fl.l_start; 435 ofl.l_len = fl.l_len; 436 ofl.l_pid = fl.l_pid; 437 ofl.l_type = fl.l_type; 438 ofl.l_whence = fl.l_whence; 439 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 440 } else if (uap->cmd == F_GETLK) { 441 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 442 } 443 return (error); 444 } 445 446 int 447 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 448 { 449 struct filedesc *fdp; 450 struct flock *flp; 451 struct file *fp, *fp2; 452 struct filedescent *fde; 453 struct proc *p; 454 struct vnode *vp; 455 cap_rights_t rights; 456 int error, flg, tmp; 457 uint64_t bsize; 458 off_t foffset; 459 460 error = 0; 461 flg = F_POSIX; 462 p = td->td_proc; 463 fdp = p->p_fd; 464 465 switch (cmd) { 466 case F_DUPFD: 467 tmp = arg; 468 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 469 break; 470 471 case F_DUPFD_CLOEXEC: 472 tmp = arg; 473 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 474 td->td_retval); 475 break; 476 477 case F_DUP2FD: 478 tmp = arg; 479 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 480 break; 481 482 case F_DUP2FD_CLOEXEC: 483 tmp = arg; 484 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 485 td->td_retval); 486 break; 487 488 case F_GETFD: 489 FILEDESC_SLOCK(fdp); 490 if (fget_locked(fdp, fd) == NULL) { 491 FILEDESC_SUNLOCK(fdp); 492 error = EBADF; 493 break; 494 } 495 fde = &fdp->fd_ofiles[fd]; 496 td->td_retval[0] = 497 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 498 FILEDESC_SUNLOCK(fdp); 499 break; 500 501 case F_SETFD: 502 FILEDESC_XLOCK(fdp); 503 if (fget_locked(fdp, fd) == NULL) { 504 FILEDESC_XUNLOCK(fdp); 505 error = EBADF; 506 break; 507 } 508 fde = &fdp->fd_ofiles[fd]; 509 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 510 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 511 FILEDESC_XUNLOCK(fdp); 512 break; 513 514 case F_GETFL: 515 error = fget_unlocked(fdp, fd, 516 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp, NULL); 517 if (error != 0) 518 break; 519 td->td_retval[0] = OFLAGS(fp->f_flag); 520 fdrop(fp, td); 521 break; 522 523 case F_SETFL: 524 error = fget_unlocked(fdp, fd, 525 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp, NULL); 526 if (error != 0) 527 break; 528 do { 529 tmp = flg = fp->f_flag; 530 tmp &= ~FCNTLFLAGS; 531 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 532 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 533 tmp = fp->f_flag & FNONBLOCK; 534 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 535 if (error != 0) { 536 fdrop(fp, td); 537 break; 538 } 539 tmp = fp->f_flag & FASYNC; 540 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 541 if (error == 0) { 542 fdrop(fp, td); 543 break; 544 } 545 atomic_clear_int(&fp->f_flag, FNONBLOCK); 546 tmp = 0; 547 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 548 fdrop(fp, td); 549 break; 550 551 case F_GETOWN: 552 error = fget_unlocked(fdp, fd, 553 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp, NULL); 554 if (error != 0) 555 break; 556 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 557 if (error == 0) 558 td->td_retval[0] = tmp; 559 fdrop(fp, td); 560 break; 561 562 case F_SETOWN: 563 error = fget_unlocked(fdp, fd, 564 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp, NULL); 565 if (error != 0) 566 break; 567 tmp = arg; 568 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 569 fdrop(fp, td); 570 break; 571 572 case F_SETLK_REMOTE: 573 error = priv_check(td, PRIV_NFS_LOCKD); 574 if (error) 575 return (error); 576 flg = F_REMOTE; 577 goto do_setlk; 578 579 case F_SETLKW: 580 flg |= F_WAIT; 581 /* FALLTHROUGH F_SETLK */ 582 583 case F_SETLK: 584 do_setlk: 585 cap_rights_init(&rights, CAP_FLOCK); 586 error = fget_unlocked(fdp, fd, &rights, 0, &fp, NULL); 587 if (error != 0) 588 break; 589 if (fp->f_type != DTYPE_VNODE) { 590 error = EBADF; 591 fdrop(fp, td); 592 break; 593 } 594 595 flp = (struct flock *)arg; 596 if (flp->l_whence == SEEK_CUR) { 597 foffset = foffset_get(fp); 598 if (foffset < 0 || 599 (flp->l_start > 0 && 600 foffset > OFF_MAX - flp->l_start)) { 601 FILEDESC_SUNLOCK(fdp); 602 error = EOVERFLOW; 603 fdrop(fp, td); 604 break; 605 } 606 flp->l_start += foffset; 607 } 608 609 vp = fp->f_vnode; 610 switch (flp->l_type) { 611 case F_RDLCK: 612 if ((fp->f_flag & FREAD) == 0) { 613 error = EBADF; 614 break; 615 } 616 PROC_LOCK(p->p_leader); 617 p->p_leader->p_flag |= P_ADVLOCK; 618 PROC_UNLOCK(p->p_leader); 619 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 620 flp, flg); 621 break; 622 case F_WRLCK: 623 if ((fp->f_flag & FWRITE) == 0) { 624 error = EBADF; 625 break; 626 } 627 PROC_LOCK(p->p_leader); 628 p->p_leader->p_flag |= P_ADVLOCK; 629 PROC_UNLOCK(p->p_leader); 630 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 631 flp, flg); 632 break; 633 case F_UNLCK: 634 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 635 flp, flg); 636 break; 637 case F_UNLCKSYS: 638 /* 639 * Temporary api for testing remote lock 640 * infrastructure. 641 */ 642 if (flg != F_REMOTE) { 643 error = EINVAL; 644 break; 645 } 646 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 647 F_UNLCKSYS, flp, flg); 648 break; 649 default: 650 error = EINVAL; 651 break; 652 } 653 if (error != 0 || flp->l_type == F_UNLCK || 654 flp->l_type == F_UNLCKSYS) { 655 fdrop(fp, td); 656 break; 657 } 658 659 /* 660 * Check for a race with close. 661 * 662 * The vnode is now advisory locked (or unlocked, but this case 663 * is not really important) as the caller requested. 664 * We had to drop the filedesc lock, so we need to recheck if 665 * the descriptor is still valid, because if it was closed 666 * in the meantime we need to remove advisory lock from the 667 * vnode - close on any descriptor leading to an advisory 668 * locked vnode, removes that lock. 669 * We will return 0 on purpose in that case, as the result of 670 * successful advisory lock might have been externally visible 671 * already. This is fine - effectively we pretend to the caller 672 * that the closing thread was a bit slower and that the 673 * advisory lock succeeded before the close. 674 */ 675 error = fget_unlocked(fdp, fd, &rights, 0, &fp2, NULL); 676 if (error != 0) { 677 fdrop(fp, td); 678 break; 679 } 680 if (fp != fp2) { 681 flp->l_whence = SEEK_SET; 682 flp->l_start = 0; 683 flp->l_len = 0; 684 flp->l_type = F_UNLCK; 685 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 686 F_UNLCK, flp, F_POSIX); 687 } 688 fdrop(fp, td); 689 fdrop(fp2, td); 690 break; 691 692 case F_GETLK: 693 error = fget_unlocked(fdp, fd, 694 cap_rights_init(&rights, CAP_FLOCK), 0, &fp, NULL); 695 if (error != 0) 696 break; 697 if (fp->f_type != DTYPE_VNODE) { 698 error = EBADF; 699 fdrop(fp, td); 700 break; 701 } 702 flp = (struct flock *)arg; 703 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 704 flp->l_type != F_UNLCK) { 705 error = EINVAL; 706 fdrop(fp, td); 707 break; 708 } 709 if (flp->l_whence == SEEK_CUR) { 710 foffset = foffset_get(fp); 711 if ((flp->l_start > 0 && 712 foffset > OFF_MAX - flp->l_start) || 713 (flp->l_start < 0 && 714 foffset < OFF_MIN - flp->l_start)) { 715 FILEDESC_SUNLOCK(fdp); 716 error = EOVERFLOW; 717 fdrop(fp, td); 718 break; 719 } 720 flp->l_start += foffset; 721 } 722 vp = fp->f_vnode; 723 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 724 F_POSIX); 725 fdrop(fp, td); 726 break; 727 728 case F_RDAHEAD: 729 arg = arg ? 128 * 1024: 0; 730 /* FALLTHROUGH */ 731 case F_READAHEAD: 732 error = fget_unlocked(fdp, fd, NULL, 0, &fp, NULL); 733 if (error != 0) 734 break; 735 if (fp->f_type != DTYPE_VNODE) { 736 fdrop(fp, td); 737 error = EBADF; 738 break; 739 } 740 vp = fp->f_vnode; 741 /* 742 * Exclusive lock synchronizes against f_seqcount reads and 743 * writes in sequential_heuristic(). 744 */ 745 error = vn_lock(vp, LK_EXCLUSIVE); 746 if (error != 0) { 747 fdrop(fp, td); 748 break; 749 } 750 if (arg >= 0) { 751 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 752 fp->f_seqcount = (arg + bsize - 1) / bsize; 753 atomic_set_int(&fp->f_flag, FRDAHEAD); 754 } else { 755 atomic_clear_int(&fp->f_flag, FRDAHEAD); 756 } 757 VOP_UNLOCK(vp, 0); 758 fdrop(fp, td); 759 break; 760 761 default: 762 error = EINVAL; 763 break; 764 } 765 return (error); 766 } 767 768 static int 769 getmaxfd(struct proc *p) 770 { 771 int maxfd; 772 773 PROC_LOCK(p); 774 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 775 PROC_UNLOCK(p); 776 777 return (maxfd); 778 } 779 780 /* 781 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 782 */ 783 int 784 do_dup(struct thread *td, int flags, int old, int new, 785 register_t *retval) 786 { 787 struct filedesc *fdp; 788 struct filedescent *oldfde, *newfde; 789 struct proc *p; 790 struct file *fp; 791 struct file *delfp; 792 int error, maxfd; 793 794 p = td->td_proc; 795 fdp = p->p_fd; 796 797 /* 798 * Verify we have a valid descriptor to dup from and possibly to 799 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 800 * return EINVAL when the new descriptor is out of bounds. 801 */ 802 if (old < 0) 803 return (EBADF); 804 if (new < 0) 805 return (flags & DUP_FCNTL ? EINVAL : EBADF); 806 maxfd = getmaxfd(p); 807 if (new >= maxfd) 808 return (flags & DUP_FCNTL ? EINVAL : EBADF); 809 810 FILEDESC_XLOCK(fdp); 811 if (fget_locked(fdp, old) == NULL) { 812 FILEDESC_XUNLOCK(fdp); 813 return (EBADF); 814 } 815 oldfde = &fdp->fd_ofiles[old]; 816 if (flags & DUP_FIXED && old == new) { 817 *retval = new; 818 if (flags & DUP_CLOEXEC) 819 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 820 FILEDESC_XUNLOCK(fdp); 821 return (0); 822 } 823 fp = oldfde->fde_file; 824 fhold(fp); 825 826 /* 827 * If the caller specified a file descriptor, make sure the file 828 * table is large enough to hold it, and grab it. Otherwise, just 829 * allocate a new descriptor the usual way. 830 */ 831 if (flags & DUP_FIXED) { 832 if (new >= fdp->fd_nfiles) { 833 /* 834 * The resource limits are here instead of e.g. 835 * fdalloc(), because the file descriptor table may be 836 * shared between processes, so we can't really use 837 * racct_add()/racct_sub(). Instead of counting the 838 * number of actually allocated descriptors, just put 839 * the limit on the size of the file descriptor table. 840 */ 841 #ifdef RACCT 842 PROC_LOCK(p); 843 error = racct_set(p, RACCT_NOFILE, new + 1); 844 PROC_UNLOCK(p); 845 if (error != 0) { 846 FILEDESC_XUNLOCK(fdp); 847 fdrop(fp, td); 848 return (EMFILE); 849 } 850 #endif 851 fdgrowtable_exp(fdp, new + 1); 852 oldfde = &fdp->fd_ofiles[old]; 853 } 854 newfde = &fdp->fd_ofiles[new]; 855 if (newfde->fde_file == NULL) 856 fdused(fdp, new); 857 } else { 858 if ((error = fdalloc(td, new, &new)) != 0) { 859 FILEDESC_XUNLOCK(fdp); 860 fdrop(fp, td); 861 return (error); 862 } 863 newfde = &fdp->fd_ofiles[new]; 864 } 865 866 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 867 KASSERT(old != new, ("new fd is same as old")); 868 869 delfp = newfde->fde_file; 870 871 /* 872 * Duplicate the source descriptor. 873 */ 874 filecaps_free(&newfde->fde_caps); 875 *newfde = *oldfde; 876 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 877 if ((flags & DUP_CLOEXEC) != 0) 878 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 879 else 880 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 881 *retval = new; 882 883 if (delfp != NULL) { 884 (void) closefp(fdp, new, delfp, td, 1); 885 /* closefp() drops the FILEDESC lock for us. */ 886 } else { 887 FILEDESC_XUNLOCK(fdp); 888 } 889 890 return (0); 891 } 892 893 /* 894 * If sigio is on the list associated with a process or process group, 895 * disable signalling from the device, remove sigio from the list and 896 * free sigio. 897 */ 898 void 899 funsetown(struct sigio **sigiop) 900 { 901 struct sigio *sigio; 902 903 SIGIO_LOCK(); 904 sigio = *sigiop; 905 if (sigio == NULL) { 906 SIGIO_UNLOCK(); 907 return; 908 } 909 *(sigio->sio_myref) = NULL; 910 if ((sigio)->sio_pgid < 0) { 911 struct pgrp *pg = (sigio)->sio_pgrp; 912 PGRP_LOCK(pg); 913 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 914 sigio, sio_pgsigio); 915 PGRP_UNLOCK(pg); 916 } else { 917 struct proc *p = (sigio)->sio_proc; 918 PROC_LOCK(p); 919 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 920 sigio, sio_pgsigio); 921 PROC_UNLOCK(p); 922 } 923 SIGIO_UNLOCK(); 924 crfree(sigio->sio_ucred); 925 free(sigio, M_SIGIO); 926 } 927 928 /* 929 * Free a list of sigio structures. 930 * We only need to lock the SIGIO_LOCK because we have made ourselves 931 * inaccessible to callers of fsetown and therefore do not need to lock 932 * the proc or pgrp struct for the list manipulation. 933 */ 934 void 935 funsetownlst(struct sigiolst *sigiolst) 936 { 937 struct proc *p; 938 struct pgrp *pg; 939 struct sigio *sigio; 940 941 sigio = SLIST_FIRST(sigiolst); 942 if (sigio == NULL) 943 return; 944 p = NULL; 945 pg = NULL; 946 947 /* 948 * Every entry of the list should belong 949 * to a single proc or pgrp. 950 */ 951 if (sigio->sio_pgid < 0) { 952 pg = sigio->sio_pgrp; 953 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 954 } else /* if (sigio->sio_pgid > 0) */ { 955 p = sigio->sio_proc; 956 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 957 } 958 959 SIGIO_LOCK(); 960 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 961 *(sigio->sio_myref) = NULL; 962 if (pg != NULL) { 963 KASSERT(sigio->sio_pgid < 0, 964 ("Proc sigio in pgrp sigio list")); 965 KASSERT(sigio->sio_pgrp == pg, 966 ("Bogus pgrp in sigio list")); 967 PGRP_LOCK(pg); 968 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 969 sio_pgsigio); 970 PGRP_UNLOCK(pg); 971 } else /* if (p != NULL) */ { 972 KASSERT(sigio->sio_pgid > 0, 973 ("Pgrp sigio in proc sigio list")); 974 KASSERT(sigio->sio_proc == p, 975 ("Bogus proc in sigio list")); 976 PROC_LOCK(p); 977 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 978 sio_pgsigio); 979 PROC_UNLOCK(p); 980 } 981 SIGIO_UNLOCK(); 982 crfree(sigio->sio_ucred); 983 free(sigio, M_SIGIO); 984 SIGIO_LOCK(); 985 } 986 SIGIO_UNLOCK(); 987 } 988 989 /* 990 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 991 * 992 * After permission checking, add a sigio structure to the sigio list for 993 * the process or process group. 994 */ 995 int 996 fsetown(pid_t pgid, struct sigio **sigiop) 997 { 998 struct proc *proc; 999 struct pgrp *pgrp; 1000 struct sigio *sigio; 1001 int ret; 1002 1003 if (pgid == 0) { 1004 funsetown(sigiop); 1005 return (0); 1006 } 1007 1008 ret = 0; 1009 1010 /* Allocate and fill in the new sigio out of locks. */ 1011 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1012 sigio->sio_pgid = pgid; 1013 sigio->sio_ucred = crhold(curthread->td_ucred); 1014 sigio->sio_myref = sigiop; 1015 1016 sx_slock(&proctree_lock); 1017 if (pgid > 0) { 1018 proc = pfind(pgid); 1019 if (proc == NULL) { 1020 ret = ESRCH; 1021 goto fail; 1022 } 1023 1024 /* 1025 * Policy - Don't allow a process to FSETOWN a process 1026 * in another session. 1027 * 1028 * Remove this test to allow maximum flexibility or 1029 * restrict FSETOWN to the current process or process 1030 * group for maximum safety. 1031 */ 1032 PROC_UNLOCK(proc); 1033 if (proc->p_session != curthread->td_proc->p_session) { 1034 ret = EPERM; 1035 goto fail; 1036 } 1037 1038 pgrp = NULL; 1039 } else /* if (pgid < 0) */ { 1040 pgrp = pgfind(-pgid); 1041 if (pgrp == NULL) { 1042 ret = ESRCH; 1043 goto fail; 1044 } 1045 PGRP_UNLOCK(pgrp); 1046 1047 /* 1048 * Policy - Don't allow a process to FSETOWN a process 1049 * in another session. 1050 * 1051 * Remove this test to allow maximum flexibility or 1052 * restrict FSETOWN to the current process or process 1053 * group for maximum safety. 1054 */ 1055 if (pgrp->pg_session != curthread->td_proc->p_session) { 1056 ret = EPERM; 1057 goto fail; 1058 } 1059 1060 proc = NULL; 1061 } 1062 funsetown(sigiop); 1063 if (pgid > 0) { 1064 PROC_LOCK(proc); 1065 /* 1066 * Since funsetownlst() is called without the proctree 1067 * locked, we need to check for P_WEXIT. 1068 * XXX: is ESRCH correct? 1069 */ 1070 if ((proc->p_flag & P_WEXIT) != 0) { 1071 PROC_UNLOCK(proc); 1072 ret = ESRCH; 1073 goto fail; 1074 } 1075 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1076 sigio->sio_proc = proc; 1077 PROC_UNLOCK(proc); 1078 } else { 1079 PGRP_LOCK(pgrp); 1080 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1081 sigio->sio_pgrp = pgrp; 1082 PGRP_UNLOCK(pgrp); 1083 } 1084 sx_sunlock(&proctree_lock); 1085 SIGIO_LOCK(); 1086 *sigiop = sigio; 1087 SIGIO_UNLOCK(); 1088 return (0); 1089 1090 fail: 1091 sx_sunlock(&proctree_lock); 1092 crfree(sigio->sio_ucred); 1093 free(sigio, M_SIGIO); 1094 return (ret); 1095 } 1096 1097 /* 1098 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1099 */ 1100 pid_t 1101 fgetown(sigiop) 1102 struct sigio **sigiop; 1103 { 1104 pid_t pgid; 1105 1106 SIGIO_LOCK(); 1107 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1108 SIGIO_UNLOCK(); 1109 return (pgid); 1110 } 1111 1112 /* 1113 * Function drops the filedesc lock on return. 1114 */ 1115 static int 1116 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1117 int holdleaders) 1118 { 1119 int error; 1120 1121 FILEDESC_XLOCK_ASSERT(fdp); 1122 1123 if (holdleaders) { 1124 if (td->td_proc->p_fdtol != NULL) { 1125 /* 1126 * Ask fdfree() to sleep to ensure that all relevant 1127 * process leaders can be traversed in closef(). 1128 */ 1129 fdp->fd_holdleaderscount++; 1130 } else { 1131 holdleaders = 0; 1132 } 1133 } 1134 1135 /* 1136 * We now hold the fp reference that used to be owned by the 1137 * descriptor array. We have to unlock the FILEDESC *AFTER* 1138 * knote_fdclose to prevent a race of the fd getting opened, a knote 1139 * added, and deleteing a knote for the new fd. 1140 */ 1141 knote_fdclose(td, fd); 1142 1143 /* 1144 * We need to notify mqueue if the object is of type mqueue. 1145 */ 1146 if (fp->f_type == DTYPE_MQUEUE) 1147 mq_fdclose(td, fd, fp); 1148 FILEDESC_XUNLOCK(fdp); 1149 1150 error = closef(fp, td); 1151 if (holdleaders) { 1152 FILEDESC_XLOCK(fdp); 1153 fdp->fd_holdleaderscount--; 1154 if (fdp->fd_holdleaderscount == 0 && 1155 fdp->fd_holdleaderswakeup != 0) { 1156 fdp->fd_holdleaderswakeup = 0; 1157 wakeup(&fdp->fd_holdleaderscount); 1158 } 1159 FILEDESC_XUNLOCK(fdp); 1160 } 1161 return (error); 1162 } 1163 1164 /* 1165 * Close a file descriptor. 1166 */ 1167 #ifndef _SYS_SYSPROTO_H_ 1168 struct close_args { 1169 int fd; 1170 }; 1171 #endif 1172 /* ARGSUSED */ 1173 int 1174 sys_close(td, uap) 1175 struct thread *td; 1176 struct close_args *uap; 1177 { 1178 1179 return (kern_close(td, uap->fd)); 1180 } 1181 1182 int 1183 kern_close(td, fd) 1184 struct thread *td; 1185 int fd; 1186 { 1187 struct filedesc *fdp; 1188 struct file *fp; 1189 1190 fdp = td->td_proc->p_fd; 1191 1192 AUDIT_SYSCLOSE(td, fd); 1193 1194 FILEDESC_XLOCK(fdp); 1195 if ((fp = fget_locked(fdp, fd)) == NULL) { 1196 FILEDESC_XUNLOCK(fdp); 1197 return (EBADF); 1198 } 1199 fdfree(fdp, fd); 1200 1201 /* closefp() drops the FILEDESC lock for us. */ 1202 return (closefp(fdp, fd, fp, td, 1)); 1203 } 1204 1205 /* 1206 * Close open file descriptors. 1207 */ 1208 #ifndef _SYS_SYSPROTO_H_ 1209 struct closefrom_args { 1210 int lowfd; 1211 }; 1212 #endif 1213 /* ARGSUSED */ 1214 int 1215 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1216 { 1217 struct filedesc *fdp; 1218 int fd; 1219 1220 fdp = td->td_proc->p_fd; 1221 AUDIT_ARG_FD(uap->lowfd); 1222 1223 /* 1224 * Treat negative starting file descriptor values identical to 1225 * closefrom(0) which closes all files. 1226 */ 1227 if (uap->lowfd < 0) 1228 uap->lowfd = 0; 1229 FILEDESC_SLOCK(fdp); 1230 for (fd = uap->lowfd; fd <= fdp->fd_lastfile; fd++) { 1231 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1232 FILEDESC_SUNLOCK(fdp); 1233 (void)kern_close(td, fd); 1234 FILEDESC_SLOCK(fdp); 1235 } 1236 } 1237 FILEDESC_SUNLOCK(fdp); 1238 return (0); 1239 } 1240 1241 #if defined(COMPAT_43) 1242 /* 1243 * Return status information about a file descriptor. 1244 */ 1245 #ifndef _SYS_SYSPROTO_H_ 1246 struct ofstat_args { 1247 int fd; 1248 struct ostat *sb; 1249 }; 1250 #endif 1251 /* ARGSUSED */ 1252 int 1253 ofstat(struct thread *td, struct ofstat_args *uap) 1254 { 1255 struct ostat oub; 1256 struct stat ub; 1257 int error; 1258 1259 error = kern_fstat(td, uap->fd, &ub); 1260 if (error == 0) { 1261 cvtstat(&ub, &oub); 1262 error = copyout(&oub, uap->sb, sizeof(oub)); 1263 } 1264 return (error); 1265 } 1266 #endif /* COMPAT_43 */ 1267 1268 /* 1269 * Return status information about a file descriptor. 1270 */ 1271 #ifndef _SYS_SYSPROTO_H_ 1272 struct fstat_args { 1273 int fd; 1274 struct stat *sb; 1275 }; 1276 #endif 1277 /* ARGSUSED */ 1278 int 1279 sys_fstat(struct thread *td, struct fstat_args *uap) 1280 { 1281 struct stat ub; 1282 int error; 1283 1284 error = kern_fstat(td, uap->fd, &ub); 1285 if (error == 0) 1286 error = copyout(&ub, uap->sb, sizeof(ub)); 1287 return (error); 1288 } 1289 1290 int 1291 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1292 { 1293 struct file *fp; 1294 cap_rights_t rights; 1295 int error; 1296 1297 AUDIT_ARG_FD(fd); 1298 1299 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1300 if (error != 0) 1301 return (error); 1302 1303 AUDIT_ARG_FILE(td->td_proc, fp); 1304 1305 error = fo_stat(fp, sbp, td->td_ucred, td); 1306 fdrop(fp, td); 1307 #ifdef KTRACE 1308 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1309 ktrstat(sbp); 1310 #endif 1311 return (error); 1312 } 1313 1314 /* 1315 * Return status information about a file descriptor. 1316 */ 1317 #ifndef _SYS_SYSPROTO_H_ 1318 struct nfstat_args { 1319 int fd; 1320 struct nstat *sb; 1321 }; 1322 #endif 1323 /* ARGSUSED */ 1324 int 1325 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1326 { 1327 struct nstat nub; 1328 struct stat ub; 1329 int error; 1330 1331 error = kern_fstat(td, uap->fd, &ub); 1332 if (error == 0) { 1333 cvtnstat(&ub, &nub); 1334 error = copyout(&nub, uap->sb, sizeof(nub)); 1335 } 1336 return (error); 1337 } 1338 1339 /* 1340 * Return pathconf information about a file descriptor. 1341 */ 1342 #ifndef _SYS_SYSPROTO_H_ 1343 struct fpathconf_args { 1344 int fd; 1345 int name; 1346 }; 1347 #endif 1348 /* ARGSUSED */ 1349 int 1350 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1351 { 1352 struct file *fp; 1353 struct vnode *vp; 1354 cap_rights_t rights; 1355 int error; 1356 1357 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1358 if (error != 0) 1359 return (error); 1360 1361 /* If asynchronous I/O is available, it works for all descriptors. */ 1362 if (uap->name == _PC_ASYNC_IO) { 1363 td->td_retval[0] = async_io_version; 1364 goto out; 1365 } 1366 vp = fp->f_vnode; 1367 if (vp != NULL) { 1368 vn_lock(vp, LK_SHARED | LK_RETRY); 1369 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1370 VOP_UNLOCK(vp, 0); 1371 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1372 if (uap->name != _PC_PIPE_BUF) { 1373 error = EINVAL; 1374 } else { 1375 td->td_retval[0] = PIPE_BUF; 1376 error = 0; 1377 } 1378 } else { 1379 error = EOPNOTSUPP; 1380 } 1381 out: 1382 fdrop(fp, td); 1383 return (error); 1384 } 1385 1386 /* 1387 * Initialize filecaps structure. 1388 */ 1389 void 1390 filecaps_init(struct filecaps *fcaps) 1391 { 1392 1393 bzero(fcaps, sizeof(*fcaps)); 1394 fcaps->fc_nioctls = -1; 1395 } 1396 1397 /* 1398 * Copy filecaps structure allocating memory for ioctls array if needed. 1399 */ 1400 void 1401 filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1402 { 1403 size_t size; 1404 1405 *dst = *src; 1406 if (src->fc_ioctls != NULL) { 1407 KASSERT(src->fc_nioctls > 0, 1408 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1409 1410 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1411 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1412 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1413 } 1414 } 1415 1416 /* 1417 * Move filecaps structure to the new place and clear the old place. 1418 */ 1419 void 1420 filecaps_move(struct filecaps *src, struct filecaps *dst) 1421 { 1422 1423 *dst = *src; 1424 bzero(src, sizeof(*src)); 1425 } 1426 1427 /* 1428 * Fill the given filecaps structure with full rights. 1429 */ 1430 static void 1431 filecaps_fill(struct filecaps *fcaps) 1432 { 1433 1434 CAP_ALL(&fcaps->fc_rights); 1435 fcaps->fc_ioctls = NULL; 1436 fcaps->fc_nioctls = -1; 1437 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1438 } 1439 1440 /* 1441 * Free memory allocated within filecaps structure. 1442 */ 1443 void 1444 filecaps_free(struct filecaps *fcaps) 1445 { 1446 1447 free(fcaps->fc_ioctls, M_FILECAPS); 1448 bzero(fcaps, sizeof(*fcaps)); 1449 } 1450 1451 /* 1452 * Validate the given filecaps structure. 1453 */ 1454 static void 1455 filecaps_validate(const struct filecaps *fcaps, const char *func) 1456 { 1457 1458 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1459 ("%s: invalid rights", func)); 1460 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1461 ("%s: invalid fcntls", func)); 1462 KASSERT(fcaps->fc_fcntls == 0 || 1463 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1464 ("%s: fcntls without CAP_FCNTL", func)); 1465 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1466 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1467 ("%s: invalid ioctls", func)); 1468 KASSERT(fcaps->fc_nioctls == 0 || 1469 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1470 ("%s: ioctls without CAP_IOCTL", func)); 1471 } 1472 1473 static void 1474 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1475 { 1476 int nfd1; 1477 1478 FILEDESC_XLOCK_ASSERT(fdp); 1479 1480 nfd1 = fdp->fd_nfiles * 2; 1481 if (nfd1 < nfd) 1482 nfd1 = nfd; 1483 fdgrowtable(fdp, nfd1); 1484 } 1485 1486 /* 1487 * Grow the file table to accomodate (at least) nfd descriptors. 1488 */ 1489 static void 1490 fdgrowtable(struct filedesc *fdp, int nfd) 1491 { 1492 struct filedesc0 *fdp0; 1493 struct freetable *ft; 1494 struct filedescent *ntable; 1495 struct filedescent *otable; 1496 int nnfiles, onfiles; 1497 NDSLOTTYPE *nmap, *omap; 1498 1499 FILEDESC_XLOCK_ASSERT(fdp); 1500 1501 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1502 1503 /* save old values */ 1504 onfiles = fdp->fd_nfiles; 1505 otable = fdp->fd_ofiles; 1506 omap = fdp->fd_map; 1507 1508 /* compute the size of the new table */ 1509 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1510 if (nnfiles <= onfiles) 1511 /* the table is already large enough */ 1512 return; 1513 1514 /* 1515 * Allocate a new table. We need enough space for the 1516 * file entries themselves and the struct freetable we will use 1517 * when we decommission the table and place it on the freelist. 1518 * We place the struct freetable in the middle so we don't have 1519 * to worry about padding. 1520 */ 1521 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1522 M_FILEDESC, M_ZERO | M_WAITOK); 1523 /* copy the old data over and point at the new tables */ 1524 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1525 fdp->fd_ofiles = ntable; 1526 1527 /* 1528 * Allocate a new map only if the old is not large enough. It will 1529 * grow at a slower rate than the table as it can map more 1530 * entries than the table can hold. 1531 */ 1532 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1533 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1534 M_ZERO | M_WAITOK); 1535 /* copy over the old data and update the pointer */ 1536 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1537 fdp->fd_map = nmap; 1538 } 1539 1540 /* 1541 * In order to have a valid pattern for fget_unlocked() 1542 * fdp->fd_nfiles must be the last member to be updated, otherwise 1543 * fget_unlocked() consumers may reference a new, higher value for 1544 * fdp->fd_nfiles before to access the fdp->fd_ofiles array, 1545 * resulting in OOB accesses. 1546 */ 1547 atomic_store_rel_int(&fdp->fd_nfiles, nnfiles); 1548 1549 /* 1550 * Do not free the old file table, as some threads may still 1551 * reference entries within it. Instead, place it on a freelist 1552 * which will be processed when the struct filedesc is released. 1553 * 1554 * Note that if onfiles == NDFILE, we're dealing with the original 1555 * static allocation contained within (struct filedesc0 *)fdp, 1556 * which must not be freed. 1557 */ 1558 if (onfiles > NDFILE) { 1559 ft = (struct freetable *)&otable[onfiles]; 1560 fdp0 = (struct filedesc0 *)fdp; 1561 ft->ft_table = otable; 1562 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1563 } 1564 /* 1565 * The map does not have the same possibility of threads still 1566 * holding references to it. So always free it as long as it 1567 * does not reference the original static allocation. 1568 */ 1569 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1570 free(omap, M_FILEDESC); 1571 } 1572 1573 /* 1574 * Allocate a file descriptor for the process. 1575 */ 1576 int 1577 fdalloc(struct thread *td, int minfd, int *result) 1578 { 1579 struct proc *p = td->td_proc; 1580 struct filedesc *fdp = p->p_fd; 1581 int fd = -1, maxfd, allocfd; 1582 #ifdef RACCT 1583 int error; 1584 #endif 1585 1586 FILEDESC_XLOCK_ASSERT(fdp); 1587 1588 if (fdp->fd_freefile > minfd) 1589 minfd = fdp->fd_freefile; 1590 1591 maxfd = getmaxfd(p); 1592 1593 /* 1594 * Search the bitmap for a free descriptor starting at minfd. 1595 * If none is found, grow the file table. 1596 */ 1597 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1598 if (fd >= maxfd) 1599 return (EMFILE); 1600 if (fd >= fdp->fd_nfiles) { 1601 allocfd = min(fd * 2, maxfd); 1602 #ifdef RACCT 1603 PROC_LOCK(p); 1604 error = racct_set(p, RACCT_NOFILE, allocfd); 1605 PROC_UNLOCK(p); 1606 if (error != 0) 1607 return (EMFILE); 1608 #endif 1609 /* 1610 * fd is already equal to first free descriptor >= minfd, so 1611 * we only need to grow the table and we are done. 1612 */ 1613 fdgrowtable_exp(fdp, allocfd); 1614 } 1615 1616 /* 1617 * Perform some sanity checks, then mark the file descriptor as 1618 * used and return it to the caller. 1619 */ 1620 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1621 ("invalid descriptor %d", fd)); 1622 KASSERT(!fdisused(fdp, fd), 1623 ("fd_first_free() returned non-free descriptor")); 1624 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1625 ("file descriptor isn't free")); 1626 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1627 fdused(fdp, fd); 1628 *result = fd; 1629 return (0); 1630 } 1631 1632 /* 1633 * Allocate n file descriptors for the process. 1634 */ 1635 int 1636 fdallocn(struct thread *td, int minfd, int *fds, int n) 1637 { 1638 struct proc *p = td->td_proc; 1639 struct filedesc *fdp = p->p_fd; 1640 int i; 1641 1642 FILEDESC_XLOCK_ASSERT(fdp); 1643 1644 for (i = 0; i < n; i++) 1645 if (fdalloc(td, 0, &fds[i]) != 0) 1646 break; 1647 1648 if (i < n) { 1649 for (i--; i >= 0; i--) 1650 fdunused(fdp, fds[i]); 1651 return (EMFILE); 1652 } 1653 1654 return (0); 1655 } 1656 1657 /* 1658 * Create a new open file structure and allocate a file decriptor for the 1659 * process that refers to it. We add one reference to the file for the 1660 * descriptor table and one reference for resultfp. This is to prevent us 1661 * being preempted and the entry in the descriptor table closed after we 1662 * release the FILEDESC lock. 1663 */ 1664 int 1665 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1666 { 1667 struct file *fp; 1668 int error, fd; 1669 1670 error = falloc_noinstall(td, &fp); 1671 if (error) 1672 return (error); /* no reference held on error */ 1673 1674 error = finstall(td, fp, &fd, flags, NULL); 1675 if (error) { 1676 fdrop(fp, td); /* one reference (fp only) */ 1677 return (error); 1678 } 1679 1680 if (resultfp != NULL) 1681 *resultfp = fp; /* copy out result */ 1682 else 1683 fdrop(fp, td); /* release local reference */ 1684 1685 if (resultfd != NULL) 1686 *resultfd = fd; 1687 1688 return (0); 1689 } 1690 1691 /* 1692 * Create a new open file structure without allocating a file descriptor. 1693 */ 1694 int 1695 falloc_noinstall(struct thread *td, struct file **resultfp) 1696 { 1697 struct file *fp; 1698 int maxuserfiles = maxfiles - (maxfiles / 20); 1699 static struct timeval lastfail; 1700 static int curfail; 1701 1702 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1703 1704 if ((openfiles >= maxuserfiles && 1705 priv_check(td, PRIV_MAXFILES) != 0) || 1706 openfiles >= maxfiles) { 1707 if (ppsratecheck(&lastfail, &curfail, 1)) { 1708 printf("kern.maxfiles limit exceeded by uid %i, " 1709 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1710 } 1711 return (ENFILE); 1712 } 1713 atomic_add_int(&openfiles, 1); 1714 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1715 refcount_init(&fp->f_count, 1); 1716 fp->f_cred = crhold(td->td_ucred); 1717 fp->f_ops = &badfileops; 1718 fp->f_data = NULL; 1719 fp->f_vnode = NULL; 1720 *resultfp = fp; 1721 return (0); 1722 } 1723 1724 /* 1725 * Install a file in a file descriptor table. 1726 */ 1727 int 1728 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1729 struct filecaps *fcaps) 1730 { 1731 struct filedesc *fdp = td->td_proc->p_fd; 1732 struct filedescent *fde; 1733 int error; 1734 1735 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1736 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1737 if (fcaps != NULL) 1738 filecaps_validate(fcaps, __func__); 1739 1740 FILEDESC_XLOCK(fdp); 1741 if ((error = fdalloc(td, 0, fd))) { 1742 FILEDESC_XUNLOCK(fdp); 1743 return (error); 1744 } 1745 fhold(fp); 1746 fde = &fdp->fd_ofiles[*fd]; 1747 fde->fde_file = fp; 1748 if ((flags & O_CLOEXEC) != 0) 1749 fde->fde_flags |= UF_EXCLOSE; 1750 if (fcaps != NULL) 1751 filecaps_move(fcaps, &fde->fde_caps); 1752 else 1753 filecaps_fill(&fde->fde_caps); 1754 FILEDESC_XUNLOCK(fdp); 1755 return (0); 1756 } 1757 1758 /* 1759 * Build a new filedesc structure from another. 1760 * Copy the current, root, and jail root vnode references. 1761 */ 1762 struct filedesc * 1763 fdinit(struct filedesc *fdp) 1764 { 1765 struct filedesc0 *newfdp; 1766 1767 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1768 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1769 if (fdp != NULL) { 1770 FILEDESC_SLOCK(fdp); 1771 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1772 if (newfdp->fd_fd.fd_cdir) 1773 VREF(newfdp->fd_fd.fd_cdir); 1774 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1775 if (newfdp->fd_fd.fd_rdir) 1776 VREF(newfdp->fd_fd.fd_rdir); 1777 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1778 if (newfdp->fd_fd.fd_jdir) 1779 VREF(newfdp->fd_fd.fd_jdir); 1780 FILEDESC_SUNLOCK(fdp); 1781 } 1782 1783 /* Create the file descriptor table. */ 1784 newfdp->fd_fd.fd_refcnt = 1; 1785 newfdp->fd_fd.fd_holdcnt = 1; 1786 newfdp->fd_fd.fd_cmask = CMASK; 1787 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1788 newfdp->fd_fd.fd_nfiles = NDFILE; 1789 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1790 newfdp->fd_fd.fd_lastfile = -1; 1791 return (&newfdp->fd_fd); 1792 } 1793 1794 static struct filedesc * 1795 fdhold(struct proc *p) 1796 { 1797 struct filedesc *fdp; 1798 1799 mtx_lock(&fdesc_mtx); 1800 fdp = p->p_fd; 1801 if (fdp != NULL) 1802 fdp->fd_holdcnt++; 1803 mtx_unlock(&fdesc_mtx); 1804 return (fdp); 1805 } 1806 1807 static void 1808 fddrop(struct filedesc *fdp) 1809 { 1810 struct filedesc0 *fdp0; 1811 struct freetable *ft; 1812 int i; 1813 1814 mtx_lock(&fdesc_mtx); 1815 i = --fdp->fd_holdcnt; 1816 mtx_unlock(&fdesc_mtx); 1817 if (i > 0) 1818 return; 1819 1820 FILEDESC_LOCK_DESTROY(fdp); 1821 fdp0 = (struct filedesc0 *)fdp; 1822 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1823 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1824 free(ft->ft_table, M_FILEDESC); 1825 } 1826 free(fdp, M_FILEDESC); 1827 } 1828 1829 /* 1830 * Share a filedesc structure. 1831 */ 1832 struct filedesc * 1833 fdshare(struct filedesc *fdp) 1834 { 1835 1836 FILEDESC_XLOCK(fdp); 1837 fdp->fd_refcnt++; 1838 FILEDESC_XUNLOCK(fdp); 1839 return (fdp); 1840 } 1841 1842 /* 1843 * Unshare a filedesc structure, if necessary by making a copy 1844 */ 1845 void 1846 fdunshare(struct thread *td) 1847 { 1848 struct filedesc *tmp; 1849 struct proc *p = td->td_proc; 1850 1851 if (p->p_fd->fd_refcnt == 1) 1852 return; 1853 1854 tmp = fdcopy(p->p_fd); 1855 fdescfree(td); 1856 p->p_fd = tmp; 1857 } 1858 1859 /* 1860 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1861 * this is to ease callers, not catch errors. 1862 */ 1863 struct filedesc * 1864 fdcopy(struct filedesc *fdp) 1865 { 1866 struct filedesc *newfdp; 1867 struct filedescent *nfde, *ofde; 1868 int i; 1869 1870 /* Certain daemons might not have file descriptors. */ 1871 if (fdp == NULL) 1872 return (NULL); 1873 1874 newfdp = fdinit(fdp); 1875 FILEDESC_SLOCK(fdp); 1876 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1877 FILEDESC_SUNLOCK(fdp); 1878 FILEDESC_XLOCK(newfdp); 1879 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1880 FILEDESC_XUNLOCK(newfdp); 1881 FILEDESC_SLOCK(fdp); 1882 } 1883 /* copy all passable descriptors (i.e. not kqueue) */ 1884 newfdp->fd_freefile = -1; 1885 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1886 ofde = &fdp->fd_ofiles[i]; 1887 if (fdisused(fdp, i) && 1888 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1889 ofde->fde_file->f_ops != &badfileops) { 1890 nfde = &newfdp->fd_ofiles[i]; 1891 *nfde = *ofde; 1892 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1893 fhold(nfde->fde_file); 1894 newfdp->fd_lastfile = i; 1895 } else { 1896 if (newfdp->fd_freefile == -1) 1897 newfdp->fd_freefile = i; 1898 } 1899 } 1900 newfdp->fd_cmask = fdp->fd_cmask; 1901 FILEDESC_SUNLOCK(fdp); 1902 FILEDESC_XLOCK(newfdp); 1903 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1904 if (newfdp->fd_ofiles[i].fde_file != NULL) 1905 fdused(newfdp, i); 1906 } 1907 if (newfdp->fd_freefile == -1) 1908 newfdp->fd_freefile = i; 1909 FILEDESC_XUNLOCK(newfdp); 1910 return (newfdp); 1911 } 1912 1913 /* 1914 * Release a filedesc structure. 1915 */ 1916 void 1917 fdescfree(struct thread *td) 1918 { 1919 struct filedesc *fdp; 1920 int i; 1921 struct filedesc_to_leader *fdtol; 1922 struct file *fp; 1923 struct vnode *cdir, *jdir, *rdir, *vp; 1924 struct flock lf; 1925 1926 /* Certain daemons might not have file descriptors. */ 1927 fdp = td->td_proc->p_fd; 1928 if (fdp == NULL) 1929 return; 1930 1931 #ifdef RACCT 1932 PROC_LOCK(td->td_proc); 1933 racct_set(td->td_proc, RACCT_NOFILE, 0); 1934 PROC_UNLOCK(td->td_proc); 1935 #endif 1936 1937 /* Check for special need to clear POSIX style locks */ 1938 fdtol = td->td_proc->p_fdtol; 1939 if (fdtol != NULL) { 1940 FILEDESC_XLOCK(fdp); 1941 KASSERT(fdtol->fdl_refcount > 0, 1942 ("filedesc_to_refcount botch: fdl_refcount=%d", 1943 fdtol->fdl_refcount)); 1944 if (fdtol->fdl_refcount == 1 && 1945 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1946 for (i = 0; i <= fdp->fd_lastfile; i++) { 1947 fp = fdp->fd_ofiles[i].fde_file; 1948 if (fp == NULL || fp->f_type != DTYPE_VNODE) 1949 continue; 1950 fhold(fp); 1951 FILEDESC_XUNLOCK(fdp); 1952 lf.l_whence = SEEK_SET; 1953 lf.l_start = 0; 1954 lf.l_len = 0; 1955 lf.l_type = F_UNLCK; 1956 vp = fp->f_vnode; 1957 (void) VOP_ADVLOCK(vp, 1958 (caddr_t)td->td_proc->p_leader, F_UNLCK, 1959 &lf, F_POSIX); 1960 FILEDESC_XLOCK(fdp); 1961 fdrop(fp, td); 1962 } 1963 } 1964 retry: 1965 if (fdtol->fdl_refcount == 1) { 1966 if (fdp->fd_holdleaderscount > 0 && 1967 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1968 /* 1969 * close() or do_dup() has cleared a reference 1970 * in a shared file descriptor table. 1971 */ 1972 fdp->fd_holdleaderswakeup = 1; 1973 sx_sleep(&fdp->fd_holdleaderscount, 1974 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 1975 goto retry; 1976 } 1977 if (fdtol->fdl_holdcount > 0) { 1978 /* 1979 * Ensure that fdtol->fdl_leader remains 1980 * valid in closef(). 1981 */ 1982 fdtol->fdl_wakeup = 1; 1983 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 1984 "fdlhold", 0); 1985 goto retry; 1986 } 1987 } 1988 fdtol->fdl_refcount--; 1989 if (fdtol->fdl_refcount == 0 && 1990 fdtol->fdl_holdcount == 0) { 1991 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 1992 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 1993 } else 1994 fdtol = NULL; 1995 td->td_proc->p_fdtol = NULL; 1996 FILEDESC_XUNLOCK(fdp); 1997 if (fdtol != NULL) 1998 free(fdtol, M_FILEDESC_TO_LEADER); 1999 } 2000 2001 mtx_lock(&fdesc_mtx); 2002 td->td_proc->p_fd = NULL; 2003 mtx_unlock(&fdesc_mtx); 2004 2005 FILEDESC_XLOCK(fdp); 2006 i = --fdp->fd_refcnt; 2007 if (i > 0) { 2008 FILEDESC_XUNLOCK(fdp); 2009 return; 2010 } 2011 2012 cdir = fdp->fd_cdir; 2013 fdp->fd_cdir = NULL; 2014 rdir = fdp->fd_rdir; 2015 fdp->fd_rdir = NULL; 2016 jdir = fdp->fd_jdir; 2017 fdp->fd_jdir = NULL; 2018 FILEDESC_XUNLOCK(fdp); 2019 2020 for (i = 0; i <= fdp->fd_lastfile; i++) { 2021 fp = fdp->fd_ofiles[i].fde_file; 2022 if (fp != NULL) { 2023 fdfree_last(fdp, i); 2024 (void) closef(fp, td); 2025 } 2026 } 2027 2028 if (fdp->fd_nfiles > NDFILE) 2029 free(fdp->fd_ofiles, M_FILEDESC); 2030 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2031 free(fdp->fd_map, M_FILEDESC); 2032 2033 if (cdir != NULL) 2034 vrele(cdir); 2035 if (rdir != NULL) 2036 vrele(rdir); 2037 if (jdir != NULL) 2038 vrele(jdir); 2039 2040 fddrop(fdp); 2041 } 2042 2043 /* 2044 * For setugid programs, we don't want to people to use that setugidness 2045 * to generate error messages which write to a file which otherwise would 2046 * otherwise be off-limits to the process. We check for filesystems where 2047 * the vnode can change out from under us after execve (like [lin]procfs). 2048 * 2049 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2050 * sufficient. We also don't check for setugidness since we know we are. 2051 */ 2052 static int 2053 is_unsafe(struct file *fp) 2054 { 2055 if (fp->f_type == DTYPE_VNODE) { 2056 struct vnode *vp = fp->f_vnode; 2057 2058 if ((vp->v_vflag & VV_PROCDEP) != 0) 2059 return (1); 2060 } 2061 return (0); 2062 } 2063 2064 /* 2065 * Make this setguid thing safe, if at all possible. 2066 */ 2067 void 2068 setugidsafety(struct thread *td) 2069 { 2070 struct filedesc *fdp; 2071 struct file *fp; 2072 int i; 2073 2074 fdp = td->td_proc->p_fd; 2075 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2076 FILEDESC_XLOCK(fdp); 2077 for (i = 0; i <= fdp->fd_lastfile; i++) { 2078 if (i > 2) 2079 break; 2080 fp = fdp->fd_ofiles[i].fde_file; 2081 if (fp != NULL && is_unsafe(fp)) { 2082 knote_fdclose(td, i); 2083 /* 2084 * NULL-out descriptor prior to close to avoid 2085 * a race while close blocks. 2086 */ 2087 fdfree(fdp, i); 2088 FILEDESC_XUNLOCK(fdp); 2089 (void) closef(fp, td); 2090 FILEDESC_XLOCK(fdp); 2091 } 2092 } 2093 FILEDESC_XUNLOCK(fdp); 2094 } 2095 2096 /* 2097 * If a specific file object occupies a specific file descriptor, close the 2098 * file descriptor entry and drop a reference on the file object. This is a 2099 * convenience function to handle a subsequent error in a function that calls 2100 * falloc() that handles the race that another thread might have closed the 2101 * file descriptor out from under the thread creating the file object. 2102 */ 2103 void 2104 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2105 { 2106 2107 FILEDESC_XLOCK(fdp); 2108 if (fdp->fd_ofiles[idx].fde_file == fp) { 2109 fdfree(fdp, idx); 2110 FILEDESC_XUNLOCK(fdp); 2111 fdrop(fp, td); 2112 } else 2113 FILEDESC_XUNLOCK(fdp); 2114 } 2115 2116 /* 2117 * Close any files on exec? 2118 */ 2119 void 2120 fdcloseexec(struct thread *td) 2121 { 2122 struct filedesc *fdp; 2123 struct filedescent *fde; 2124 struct file *fp; 2125 int i; 2126 2127 fdp = td->td_proc->p_fd; 2128 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2129 FILEDESC_XLOCK(fdp); 2130 for (i = 0; i <= fdp->fd_lastfile; i++) { 2131 fde = &fdp->fd_ofiles[i]; 2132 fp = fde->fde_file; 2133 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2134 (fde->fde_flags & UF_EXCLOSE))) { 2135 fdfree(fdp, i); 2136 (void) closefp(fdp, i, fp, td, 0); 2137 /* closefp() drops the FILEDESC lock. */ 2138 FILEDESC_XLOCK(fdp); 2139 } 2140 } 2141 FILEDESC_XUNLOCK(fdp); 2142 } 2143 2144 /* 2145 * It is unsafe for set[ug]id processes to be started with file 2146 * descriptors 0..2 closed, as these descriptors are given implicit 2147 * significance in the Standard C library. fdcheckstd() will create a 2148 * descriptor referencing /dev/null for each of stdin, stdout, and 2149 * stderr that is not already open. 2150 */ 2151 int 2152 fdcheckstd(struct thread *td) 2153 { 2154 struct filedesc *fdp; 2155 register_t retval, save; 2156 int i, error, devnull; 2157 2158 fdp = td->td_proc->p_fd; 2159 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2160 devnull = -1; 2161 error = 0; 2162 for (i = 0; i < 3; i++) { 2163 if (fdp->fd_ofiles[i].fde_file != NULL) 2164 continue; 2165 if (devnull < 0) { 2166 save = td->td_retval[0]; 2167 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2168 O_RDWR, 0); 2169 devnull = td->td_retval[0]; 2170 td->td_retval[0] = save; 2171 if (error) 2172 break; 2173 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2174 } else { 2175 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2176 if (error != 0) 2177 break; 2178 } 2179 } 2180 return (error); 2181 } 2182 2183 /* 2184 * Internal form of close. Decrement reference count on file structure. 2185 * Note: td may be NULL when closing a file that was being passed in a 2186 * message. 2187 * 2188 * XXXRW: Giant is not required for the caller, but often will be held; this 2189 * makes it moderately likely the Giant will be recursed in the VFS case. 2190 */ 2191 int 2192 closef(struct file *fp, struct thread *td) 2193 { 2194 struct vnode *vp; 2195 struct flock lf; 2196 struct filedesc_to_leader *fdtol; 2197 struct filedesc *fdp; 2198 2199 /* 2200 * POSIX record locking dictates that any close releases ALL 2201 * locks owned by this process. This is handled by setting 2202 * a flag in the unlock to free ONLY locks obeying POSIX 2203 * semantics, and not to free BSD-style file locks. 2204 * If the descriptor was in a message, POSIX-style locks 2205 * aren't passed with the descriptor, and the thread pointer 2206 * will be NULL. Callers should be careful only to pass a 2207 * NULL thread pointer when there really is no owning 2208 * context that might have locks, or the locks will be 2209 * leaked. 2210 */ 2211 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2212 vp = fp->f_vnode; 2213 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2214 lf.l_whence = SEEK_SET; 2215 lf.l_start = 0; 2216 lf.l_len = 0; 2217 lf.l_type = F_UNLCK; 2218 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2219 F_UNLCK, &lf, F_POSIX); 2220 } 2221 fdtol = td->td_proc->p_fdtol; 2222 if (fdtol != NULL) { 2223 /* 2224 * Handle special case where file descriptor table is 2225 * shared between multiple process leaders. 2226 */ 2227 fdp = td->td_proc->p_fd; 2228 FILEDESC_XLOCK(fdp); 2229 for (fdtol = fdtol->fdl_next; 2230 fdtol != td->td_proc->p_fdtol; 2231 fdtol = fdtol->fdl_next) { 2232 if ((fdtol->fdl_leader->p_flag & 2233 P_ADVLOCK) == 0) 2234 continue; 2235 fdtol->fdl_holdcount++; 2236 FILEDESC_XUNLOCK(fdp); 2237 lf.l_whence = SEEK_SET; 2238 lf.l_start = 0; 2239 lf.l_len = 0; 2240 lf.l_type = F_UNLCK; 2241 vp = fp->f_vnode; 2242 (void) VOP_ADVLOCK(vp, 2243 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2244 F_POSIX); 2245 FILEDESC_XLOCK(fdp); 2246 fdtol->fdl_holdcount--; 2247 if (fdtol->fdl_holdcount == 0 && 2248 fdtol->fdl_wakeup != 0) { 2249 fdtol->fdl_wakeup = 0; 2250 wakeup(fdtol); 2251 } 2252 } 2253 FILEDESC_XUNLOCK(fdp); 2254 } 2255 } 2256 return (fdrop(fp, td)); 2257 } 2258 2259 /* 2260 * Initialize the file pointer with the specified properties. 2261 * 2262 * The ops are set with release semantics to be certain that the flags, type, 2263 * and data are visible when ops is. This is to prevent ops methods from being 2264 * called with bad data. 2265 */ 2266 void 2267 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2268 { 2269 fp->f_data = data; 2270 fp->f_flag = flag; 2271 fp->f_type = type; 2272 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2273 } 2274 2275 int 2276 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2277 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2278 { 2279 #ifdef CAPABILITIES 2280 struct filedescent fde; 2281 #endif 2282 struct file *fp; 2283 u_int count; 2284 #ifdef CAPABILITIES 2285 cap_rights_t haverights; 2286 int error; 2287 #endif 2288 2289 /* 2290 * Avoid reads reordering and then a first access to the 2291 * fdp->fd_ofiles table which could result in OOB operation. 2292 */ 2293 if (fd < 0 || fd >= atomic_load_acq_int(&fdp->fd_nfiles)) 2294 return (EBADF); 2295 /* 2296 * Fetch the descriptor locklessly. We avoid fdrop() races by 2297 * never raising a refcount above 0. To accomplish this we have 2298 * to use a cmpset loop rather than an atomic_add. The descriptor 2299 * must be re-verified once we acquire a reference to be certain 2300 * that the identity is still correct and we did not lose a race 2301 * due to preemption. 2302 */ 2303 for (;;) { 2304 #ifdef CAPABILITIES 2305 fde = fdp->fd_ofiles[fd]; 2306 fp = fde.fde_file; 2307 #else 2308 fp = fdp->fd_ofiles[fd].fde_file; 2309 #endif 2310 if (fp == NULL) 2311 return (EBADF); 2312 #ifdef CAPABILITIES 2313 haverights = *cap_rights_fde(&fde); 2314 if (needrightsp != NULL) { 2315 error = cap_check(&haverights, needrightsp); 2316 if (error != 0) 2317 return (error); 2318 if (cap_rights_is_set(needrightsp, CAP_FCNTL)) { 2319 error = cap_fcntl_check_fde(&fde, needfcntl); 2320 if (error != 0) 2321 return (error); 2322 } 2323 } 2324 #endif 2325 count = fp->f_count; 2326 if (count == 0) 2327 continue; 2328 /* 2329 * Use an acquire barrier to prevent caching of fd_ofiles 2330 * so it is refreshed for verification. 2331 */ 2332 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2333 continue; 2334 if (fp == fdp->fd_ofiles[fd].fde_file) 2335 break; 2336 fdrop(fp, curthread); 2337 } 2338 *fpp = fp; 2339 if (haverightsp != NULL) { 2340 #ifdef CAPABILITIES 2341 *haverightsp = haverights; 2342 #else 2343 CAP_ALL(haverightsp); 2344 #endif 2345 } 2346 return (0); 2347 } 2348 2349 /* 2350 * Extract the file pointer associated with the specified descriptor for the 2351 * current user process. 2352 * 2353 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2354 * returned. 2355 * 2356 * File's rights will be checked against the capability rights mask. 2357 * 2358 * If an error occured the non-zero error is returned and *fpp is set to 2359 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2360 * responsible for fdrop(). 2361 */ 2362 static __inline int 2363 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2364 cap_rights_t *needrightsp, u_char *maxprotp) 2365 { 2366 struct filedesc *fdp; 2367 struct file *fp; 2368 cap_rights_t haverights, needrights; 2369 int error; 2370 2371 *fpp = NULL; 2372 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2373 return (EBADF); 2374 if (needrightsp != NULL) 2375 needrights = *needrightsp; 2376 else 2377 cap_rights_init(&needrights); 2378 if (maxprotp != NULL) 2379 cap_rights_set(&needrights, CAP_MMAP); 2380 error = fget_unlocked(fdp, fd, &needrights, 0, &fp, &haverights); 2381 if (error != 0) 2382 return (error); 2383 if (fp->f_ops == &badfileops) { 2384 fdrop(fp, td); 2385 return (EBADF); 2386 } 2387 2388 #ifdef CAPABILITIES 2389 /* 2390 * If requested, convert capability rights to access flags. 2391 */ 2392 if (maxprotp != NULL) 2393 *maxprotp = cap_rights_to_vmprot(&haverights); 2394 #else /* !CAPABILITIES */ 2395 if (maxprotp != NULL) 2396 *maxprotp = VM_PROT_ALL; 2397 #endif /* CAPABILITIES */ 2398 2399 /* 2400 * FREAD and FWRITE failure return EBADF as per POSIX. 2401 */ 2402 error = 0; 2403 switch (flags) { 2404 case FREAD: 2405 case FWRITE: 2406 if ((fp->f_flag & flags) == 0) 2407 error = EBADF; 2408 break; 2409 case FEXEC: 2410 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2411 ((fp->f_flag & FWRITE) != 0)) 2412 error = EBADF; 2413 break; 2414 case 0: 2415 break; 2416 default: 2417 KASSERT(0, ("wrong flags")); 2418 } 2419 2420 if (error != 0) { 2421 fdrop(fp, td); 2422 return (error); 2423 } 2424 2425 *fpp = fp; 2426 return (0); 2427 } 2428 2429 int 2430 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2431 { 2432 2433 return(_fget(td, fd, fpp, 0, rightsp, NULL)); 2434 } 2435 2436 int 2437 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2438 struct file **fpp) 2439 { 2440 2441 return (_fget(td, fd, fpp, 0, rightsp, maxprotp)); 2442 } 2443 2444 int 2445 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2446 { 2447 2448 return(_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2449 } 2450 2451 int 2452 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2453 { 2454 2455 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2456 } 2457 2458 /* 2459 * Like fget() but loads the underlying vnode, or returns an error if the 2460 * descriptor does not represent a vnode. Note that pipes use vnodes but 2461 * never have VM objects. The returned vnode will be vref()'d. 2462 * 2463 * XXX: what about the unused flags ? 2464 */ 2465 static __inline int 2466 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2467 struct vnode **vpp) 2468 { 2469 struct file *fp; 2470 int error; 2471 2472 *vpp = NULL; 2473 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2474 if (error != 0) 2475 return (error); 2476 if (fp->f_vnode == NULL) { 2477 error = EINVAL; 2478 } else { 2479 *vpp = fp->f_vnode; 2480 vref(*vpp); 2481 } 2482 fdrop(fp, td); 2483 2484 return (error); 2485 } 2486 2487 int 2488 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2489 { 2490 2491 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2492 } 2493 2494 int 2495 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2496 struct filecaps *havecaps, struct vnode **vpp) 2497 { 2498 struct filedesc *fdp; 2499 struct file *fp; 2500 #ifdef CAPABILITIES 2501 int error; 2502 #endif 2503 2504 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2505 return (EBADF); 2506 2507 fp = fget_locked(fdp, fd); 2508 if (fp == NULL || fp->f_ops == &badfileops) 2509 return (EBADF); 2510 2511 #ifdef CAPABILITIES 2512 if (needrightsp != NULL) { 2513 error = cap_check(cap_rights(fdp, fd), needrightsp); 2514 if (error != 0) 2515 return (error); 2516 } 2517 #endif 2518 2519 if (fp->f_vnode == NULL) 2520 return (EINVAL); 2521 2522 *vpp = fp->f_vnode; 2523 vref(*vpp); 2524 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2525 2526 return (0); 2527 } 2528 2529 int 2530 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2531 { 2532 2533 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2534 } 2535 2536 int 2537 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2538 { 2539 2540 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2541 } 2542 2543 #ifdef notyet 2544 int 2545 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2546 struct vnode **vpp) 2547 { 2548 2549 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2550 } 2551 #endif 2552 2553 /* 2554 * Like fget() but loads the underlying socket, or returns an error if the 2555 * descriptor does not represent a socket. 2556 * 2557 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2558 * in the future. 2559 * 2560 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2561 * on their file descriptor reference to prevent the socket from being free'd 2562 * during use. 2563 */ 2564 int 2565 fgetsock(struct thread *td, int fd, cap_rights_t *rightsp, struct socket **spp, 2566 u_int *fflagp) 2567 { 2568 struct file *fp; 2569 int error; 2570 2571 *spp = NULL; 2572 if (fflagp != NULL) 2573 *fflagp = 0; 2574 if ((error = _fget(td, fd, &fp, 0, rightsp, NULL)) != 0) 2575 return (error); 2576 if (fp->f_type != DTYPE_SOCKET) { 2577 error = ENOTSOCK; 2578 } else { 2579 *spp = fp->f_data; 2580 if (fflagp) 2581 *fflagp = fp->f_flag; 2582 SOCK_LOCK(*spp); 2583 soref(*spp); 2584 SOCK_UNLOCK(*spp); 2585 } 2586 fdrop(fp, td); 2587 2588 return (error); 2589 } 2590 2591 /* 2592 * Drop the reference count on the socket and XXX release the SX lock in the 2593 * future. The last reference closes the socket. 2594 * 2595 * Note: fputsock() is deprecated, see comment for fgetsock(). 2596 */ 2597 void 2598 fputsock(struct socket *so) 2599 { 2600 2601 ACCEPT_LOCK(); 2602 SOCK_LOCK(so); 2603 CURVNET_SET(so->so_vnet); 2604 sorele(so); 2605 CURVNET_RESTORE(); 2606 } 2607 2608 /* 2609 * Handle the last reference to a file being closed. 2610 */ 2611 int 2612 _fdrop(struct file *fp, struct thread *td) 2613 { 2614 int error; 2615 2616 error = 0; 2617 if (fp->f_count != 0) 2618 panic("fdrop: count %d", fp->f_count); 2619 if (fp->f_ops != &badfileops) 2620 error = fo_close(fp, td); 2621 atomic_subtract_int(&openfiles, 1); 2622 crfree(fp->f_cred); 2623 free(fp->f_advice, M_FADVISE); 2624 uma_zfree(file_zone, fp); 2625 2626 return (error); 2627 } 2628 2629 /* 2630 * Apply an advisory lock on a file descriptor. 2631 * 2632 * Just attempt to get a record lock of the requested type on the entire file 2633 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2634 */ 2635 #ifndef _SYS_SYSPROTO_H_ 2636 struct flock_args { 2637 int fd; 2638 int how; 2639 }; 2640 #endif 2641 /* ARGSUSED */ 2642 int 2643 sys_flock(struct thread *td, struct flock_args *uap) 2644 { 2645 struct file *fp; 2646 struct vnode *vp; 2647 struct flock lf; 2648 cap_rights_t rights; 2649 int error; 2650 2651 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2652 if (error != 0) 2653 return (error); 2654 if (fp->f_type != DTYPE_VNODE) { 2655 fdrop(fp, td); 2656 return (EOPNOTSUPP); 2657 } 2658 2659 vp = fp->f_vnode; 2660 lf.l_whence = SEEK_SET; 2661 lf.l_start = 0; 2662 lf.l_len = 0; 2663 if (uap->how & LOCK_UN) { 2664 lf.l_type = F_UNLCK; 2665 atomic_clear_int(&fp->f_flag, FHASLOCK); 2666 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2667 goto done2; 2668 } 2669 if (uap->how & LOCK_EX) 2670 lf.l_type = F_WRLCK; 2671 else if (uap->how & LOCK_SH) 2672 lf.l_type = F_RDLCK; 2673 else { 2674 error = EBADF; 2675 goto done2; 2676 } 2677 atomic_set_int(&fp->f_flag, FHASLOCK); 2678 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2679 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2680 done2: 2681 fdrop(fp, td); 2682 return (error); 2683 } 2684 /* 2685 * Duplicate the specified descriptor to a free descriptor. 2686 */ 2687 int 2688 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2689 int openerror, int *indxp) 2690 { 2691 struct file *fp; 2692 int error, indx; 2693 2694 KASSERT(openerror == ENODEV || openerror == ENXIO, 2695 ("unexpected error %d in %s", openerror, __func__)); 2696 2697 /* 2698 * If the to-be-dup'd fd number is greater than the allowed number 2699 * of file descriptors, or the fd to be dup'd has already been 2700 * closed, then reject. 2701 */ 2702 FILEDESC_XLOCK(fdp); 2703 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2704 FILEDESC_XUNLOCK(fdp); 2705 return (EBADF); 2706 } 2707 2708 error = fdalloc(td, 0, &indx); 2709 if (error != 0) { 2710 FILEDESC_XUNLOCK(fdp); 2711 return (error); 2712 } 2713 2714 /* 2715 * There are two cases of interest here. 2716 * 2717 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2718 * 2719 * For ENXIO steal away the file structure from (dfd) and store it in 2720 * (indx). (dfd) is effectively closed by this operation. 2721 */ 2722 switch (openerror) { 2723 case ENODEV: 2724 /* 2725 * Check that the mode the file is being opened for is a 2726 * subset of the mode of the existing descriptor. 2727 */ 2728 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2729 fdunused(fdp, indx); 2730 FILEDESC_XUNLOCK(fdp); 2731 return (EACCES); 2732 } 2733 fhold(fp); 2734 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2735 filecaps_copy(&fdp->fd_ofiles[dfd].fde_caps, 2736 &fdp->fd_ofiles[indx].fde_caps); 2737 break; 2738 case ENXIO: 2739 /* 2740 * Steal away the file pointer from dfd and stuff it into indx. 2741 */ 2742 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2743 bzero(&fdp->fd_ofiles[dfd], sizeof(fdp->fd_ofiles[dfd])); 2744 fdunused(fdp, dfd); 2745 break; 2746 } 2747 FILEDESC_XUNLOCK(fdp); 2748 *indxp = indx; 2749 return (0); 2750 } 2751 2752 /* 2753 * Scan all active processes and prisons to see if any of them have a current 2754 * or root directory of `olddp'. If so, replace them with the new mount point. 2755 */ 2756 void 2757 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2758 { 2759 struct filedesc *fdp; 2760 struct prison *pr; 2761 struct proc *p; 2762 int nrele; 2763 2764 if (vrefcnt(olddp) == 1) 2765 return; 2766 nrele = 0; 2767 sx_slock(&allproc_lock); 2768 FOREACH_PROC_IN_SYSTEM(p) { 2769 fdp = fdhold(p); 2770 if (fdp == NULL) 2771 continue; 2772 FILEDESC_XLOCK(fdp); 2773 if (fdp->fd_cdir == olddp) { 2774 vref(newdp); 2775 fdp->fd_cdir = newdp; 2776 nrele++; 2777 } 2778 if (fdp->fd_rdir == olddp) { 2779 vref(newdp); 2780 fdp->fd_rdir = newdp; 2781 nrele++; 2782 } 2783 if (fdp->fd_jdir == olddp) { 2784 vref(newdp); 2785 fdp->fd_jdir = newdp; 2786 nrele++; 2787 } 2788 FILEDESC_XUNLOCK(fdp); 2789 fddrop(fdp); 2790 } 2791 sx_sunlock(&allproc_lock); 2792 if (rootvnode == olddp) { 2793 vref(newdp); 2794 rootvnode = newdp; 2795 nrele++; 2796 } 2797 mtx_lock(&prison0.pr_mtx); 2798 if (prison0.pr_root == olddp) { 2799 vref(newdp); 2800 prison0.pr_root = newdp; 2801 nrele++; 2802 } 2803 mtx_unlock(&prison0.pr_mtx); 2804 sx_slock(&allprison_lock); 2805 TAILQ_FOREACH(pr, &allprison, pr_list) { 2806 mtx_lock(&pr->pr_mtx); 2807 if (pr->pr_root == olddp) { 2808 vref(newdp); 2809 pr->pr_root = newdp; 2810 nrele++; 2811 } 2812 mtx_unlock(&pr->pr_mtx); 2813 } 2814 sx_sunlock(&allprison_lock); 2815 while (nrele--) 2816 vrele(olddp); 2817 } 2818 2819 struct filedesc_to_leader * 2820 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2821 { 2822 struct filedesc_to_leader *fdtol; 2823 2824 fdtol = malloc(sizeof(struct filedesc_to_leader), 2825 M_FILEDESC_TO_LEADER, 2826 M_WAITOK); 2827 fdtol->fdl_refcount = 1; 2828 fdtol->fdl_holdcount = 0; 2829 fdtol->fdl_wakeup = 0; 2830 fdtol->fdl_leader = leader; 2831 if (old != NULL) { 2832 FILEDESC_XLOCK(fdp); 2833 fdtol->fdl_next = old->fdl_next; 2834 fdtol->fdl_prev = old; 2835 old->fdl_next = fdtol; 2836 fdtol->fdl_next->fdl_prev = fdtol; 2837 FILEDESC_XUNLOCK(fdp); 2838 } else { 2839 fdtol->fdl_next = fdtol; 2840 fdtol->fdl_prev = fdtol; 2841 } 2842 return (fdtol); 2843 } 2844 2845 /* 2846 * Get file structures globally. 2847 */ 2848 static int 2849 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2850 { 2851 struct xfile xf; 2852 struct filedesc *fdp; 2853 struct file *fp; 2854 struct proc *p; 2855 int error, n; 2856 2857 error = sysctl_wire_old_buffer(req, 0); 2858 if (error != 0) 2859 return (error); 2860 if (req->oldptr == NULL) { 2861 n = 0; 2862 sx_slock(&allproc_lock); 2863 FOREACH_PROC_IN_SYSTEM(p) { 2864 if (p->p_state == PRS_NEW) 2865 continue; 2866 fdp = fdhold(p); 2867 if (fdp == NULL) 2868 continue; 2869 /* overestimates sparse tables. */ 2870 if (fdp->fd_lastfile > 0) 2871 n += fdp->fd_lastfile; 2872 fddrop(fdp); 2873 } 2874 sx_sunlock(&allproc_lock); 2875 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2876 } 2877 error = 0; 2878 bzero(&xf, sizeof(xf)); 2879 xf.xf_size = sizeof(xf); 2880 sx_slock(&allproc_lock); 2881 FOREACH_PROC_IN_SYSTEM(p) { 2882 PROC_LOCK(p); 2883 if (p->p_state == PRS_NEW) { 2884 PROC_UNLOCK(p); 2885 continue; 2886 } 2887 if (p_cansee(req->td, p) != 0) { 2888 PROC_UNLOCK(p); 2889 continue; 2890 } 2891 xf.xf_pid = p->p_pid; 2892 xf.xf_uid = p->p_ucred->cr_uid; 2893 PROC_UNLOCK(p); 2894 fdp = fdhold(p); 2895 if (fdp == NULL) 2896 continue; 2897 FILEDESC_SLOCK(fdp); 2898 for (n = 0; fdp->fd_refcnt > 0 && n <= fdp->fd_lastfile; ++n) { 2899 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 2900 continue; 2901 xf.xf_fd = n; 2902 xf.xf_file = fp; 2903 xf.xf_data = fp->f_data; 2904 xf.xf_vnode = fp->f_vnode; 2905 xf.xf_type = fp->f_type; 2906 xf.xf_count = fp->f_count; 2907 xf.xf_msgcount = 0; 2908 xf.xf_offset = foffset_get(fp); 2909 xf.xf_flag = fp->f_flag; 2910 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2911 if (error) 2912 break; 2913 } 2914 FILEDESC_SUNLOCK(fdp); 2915 fddrop(fdp); 2916 if (error) 2917 break; 2918 } 2919 sx_sunlock(&allproc_lock); 2920 return (error); 2921 } 2922 2923 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 2924 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2925 2926 #ifdef KINFO_FILE_SIZE 2927 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 2928 #endif 2929 2930 static int 2931 xlate_fflags(int fflags) 2932 { 2933 static const struct { 2934 int fflag; 2935 int kf_fflag; 2936 } fflags_table[] = { 2937 { FAPPEND, KF_FLAG_APPEND }, 2938 { FASYNC, KF_FLAG_ASYNC }, 2939 { FFSYNC, KF_FLAG_FSYNC }, 2940 { FHASLOCK, KF_FLAG_HASLOCK }, 2941 { FNONBLOCK, KF_FLAG_NONBLOCK }, 2942 { FREAD, KF_FLAG_READ }, 2943 { FWRITE, KF_FLAG_WRITE }, 2944 { O_CREAT, KF_FLAG_CREAT }, 2945 { O_DIRECT, KF_FLAG_DIRECT }, 2946 { O_EXCL, KF_FLAG_EXCL }, 2947 { O_EXEC, KF_FLAG_EXEC }, 2948 { O_EXLOCK, KF_FLAG_EXLOCK }, 2949 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 2950 { O_SHLOCK, KF_FLAG_SHLOCK }, 2951 { O_TRUNC, KF_FLAG_TRUNC } 2952 }; 2953 unsigned int i; 2954 int kflags; 2955 2956 kflags = 0; 2957 for (i = 0; i < nitems(fflags_table); i++) 2958 if (fflags & fflags_table[i].fflag) 2959 kflags |= fflags_table[i].kf_fflag; 2960 return (kflags); 2961 } 2962 2963 /* Trim unused data from kf_path by truncating the structure size. */ 2964 static void 2965 pack_kinfo(struct kinfo_file *kif) 2966 { 2967 2968 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 2969 strlen(kif->kf_path) + 1; 2970 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 2971 } 2972 2973 static void 2974 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp, 2975 struct kinfo_file *kif, struct filedesc *fdp) 2976 { 2977 int error; 2978 2979 bzero(kif, sizeof(*kif)); 2980 2981 /* Set a default type to allow for empty fill_kinfo() methods. */ 2982 kif->kf_type = KF_TYPE_UNKNOWN; 2983 kif->kf_flags = xlate_fflags(fp->f_flag); 2984 if (rightsp != NULL) 2985 kif->kf_cap_rights = *rightsp; 2986 else 2987 cap_rights_init(&kif->kf_cap_rights); 2988 kif->kf_fd = fd; 2989 kif->kf_ref_count = fp->f_count; 2990 kif->kf_offset = foffset_get(fp); 2991 2992 /* 2993 * This may drop the filedesc lock, so the 'fp' cannot be 2994 * accessed after this call. 2995 */ 2996 error = fo_fill_kinfo(fp, kif, fdp); 2997 if (error == 0) 2998 kif->kf_status |= KF_ATTR_VALID; 2999 pack_kinfo(kif); 3000 } 3001 3002 static void 3003 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags, 3004 struct kinfo_file *kif) 3005 { 3006 int error; 3007 3008 bzero(kif, sizeof(*kif)); 3009 3010 kif->kf_type = KF_TYPE_VNODE; 3011 error = vn_fill_kinfo_vnode(vp, kif); 3012 if (error == 0) 3013 kif->kf_status |= KF_ATTR_VALID; 3014 kif->kf_flags = xlate_fflags(fflags); 3015 kif->kf_fd = fd; 3016 kif->kf_ref_count = -1; 3017 kif->kf_offset = -1; 3018 pack_kinfo(kif); 3019 vrele(vp); 3020 } 3021 3022 struct export_fd_buf { 3023 struct filedesc *fdp; 3024 struct sbuf *sb; 3025 ssize_t remainder; 3026 struct kinfo_file kif; 3027 }; 3028 3029 static int 3030 export_kinfo_to_sb(struct export_fd_buf *efbuf) 3031 { 3032 struct kinfo_file *kif; 3033 3034 kif = &efbuf->kif; 3035 if (efbuf->remainder != -1) { 3036 if (efbuf->remainder < kif->kf_structsize) { 3037 /* Terminate export. */ 3038 efbuf->remainder = 0; 3039 return (0); 3040 } 3041 efbuf->remainder -= kif->kf_structsize; 3042 } 3043 return (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize)); 3044 } 3045 3046 static int 3047 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp, 3048 struct export_fd_buf *efbuf) 3049 { 3050 int error; 3051 3052 if (efbuf->remainder == 0) 3053 return (0); 3054 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp); 3055 FILEDESC_SUNLOCK(efbuf->fdp); 3056 error = export_kinfo_to_sb(efbuf); 3057 FILEDESC_SLOCK(efbuf->fdp); 3058 return (error); 3059 } 3060 3061 static int 3062 export_vnode_to_sb(struct vnode *vp, int fd, int fflags, 3063 struct export_fd_buf *efbuf) 3064 { 3065 int error; 3066 3067 if (efbuf->remainder == 0) 3068 return (0); 3069 if (efbuf->fdp != NULL) 3070 FILEDESC_SUNLOCK(efbuf->fdp); 3071 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif); 3072 error = export_kinfo_to_sb(efbuf); 3073 if (efbuf->fdp != NULL) 3074 FILEDESC_SLOCK(efbuf->fdp); 3075 return (error); 3076 } 3077 3078 /* 3079 * Store a process file descriptor information to sbuf. 3080 * 3081 * Takes a locked proc as argument, and returns with the proc unlocked. 3082 */ 3083 int 3084 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3085 { 3086 struct thread *td; 3087 struct file *fp; 3088 struct filedesc *fdp; 3089 struct export_fd_buf *efbuf; 3090 struct vnode *cttyvp, *textvp, *tracevp; 3091 int error, i; 3092 cap_rights_t rights; 3093 3094 td = curthread; 3095 PROC_LOCK_ASSERT(p, MA_OWNED); 3096 3097 /* ktrace vnode */ 3098 tracevp = p->p_tracevp; 3099 if (tracevp != NULL) 3100 vref(tracevp); 3101 /* text vnode */ 3102 textvp = p->p_textvp; 3103 if (textvp != NULL) 3104 vref(textvp); 3105 /* Controlling tty. */ 3106 cttyvp = NULL; 3107 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3108 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3109 if (cttyvp != NULL) 3110 vref(cttyvp); 3111 } 3112 fdp = fdhold(p); 3113 PROC_UNLOCK(p); 3114 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3115 efbuf->fdp = NULL; 3116 efbuf->sb = sb; 3117 efbuf->remainder = maxlen; 3118 if (tracevp != NULL) 3119 export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE, FREAD | FWRITE, 3120 efbuf); 3121 if (textvp != NULL) 3122 export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD, efbuf); 3123 if (cttyvp != NULL) 3124 export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY, FREAD | FWRITE, 3125 efbuf); 3126 error = 0; 3127 if (fdp == NULL) 3128 goto fail; 3129 efbuf->fdp = fdp; 3130 FILEDESC_SLOCK(fdp); 3131 /* working directory */ 3132 if (fdp->fd_cdir != NULL) { 3133 vref(fdp->fd_cdir); 3134 export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD, FREAD, efbuf); 3135 } 3136 /* root directory */ 3137 if (fdp->fd_rdir != NULL) { 3138 vref(fdp->fd_rdir); 3139 export_vnode_to_sb(fdp->fd_rdir, KF_FD_TYPE_ROOT, FREAD, efbuf); 3140 } 3141 /* jail directory */ 3142 if (fdp->fd_jdir != NULL) { 3143 vref(fdp->fd_jdir); 3144 export_vnode_to_sb(fdp->fd_jdir, KF_FD_TYPE_JAIL, FREAD, efbuf); 3145 } 3146 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3147 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3148 continue; 3149 #ifdef CAPABILITIES 3150 rights = *cap_rights(fdp, i); 3151 #else /* !CAPABILITIES */ 3152 cap_rights_init(&rights); 3153 #endif 3154 /* 3155 * Create sysctl entry. It is OK to drop the filedesc 3156 * lock inside of export_file_to_sb() as we will 3157 * re-validate and re-evaluate its properties when the 3158 * loop continues. 3159 */ 3160 error = export_file_to_sb(fp, i, &rights, efbuf); 3161 if (error != 0 || efbuf->remainder == 0) 3162 break; 3163 } 3164 FILEDESC_SUNLOCK(fdp); 3165 fddrop(fdp); 3166 fail: 3167 free(efbuf, M_TEMP); 3168 return (error); 3169 } 3170 3171 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3172 3173 /* 3174 * Get per-process file descriptors for use by procstat(1), et al. 3175 */ 3176 static int 3177 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3178 { 3179 struct sbuf sb; 3180 struct proc *p; 3181 ssize_t maxlen; 3182 int error, error2, *name; 3183 3184 name = (int *)arg1; 3185 3186 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3187 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3188 if (error != 0) { 3189 sbuf_delete(&sb); 3190 return (error); 3191 } 3192 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3193 error = kern_proc_filedesc_out(p, &sb, maxlen); 3194 error2 = sbuf_finish(&sb); 3195 sbuf_delete(&sb); 3196 return (error != 0 ? error : error2); 3197 } 3198 3199 #ifdef KINFO_OFILE_SIZE 3200 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 3201 #endif 3202 3203 #ifdef COMPAT_FREEBSD7 3204 static void 3205 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif) 3206 { 3207 3208 okif->kf_structsize = sizeof(*okif); 3209 okif->kf_type = kif->kf_type; 3210 okif->kf_fd = kif->kf_fd; 3211 okif->kf_ref_count = kif->kf_ref_count; 3212 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE | 3213 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK | 3214 KF_FLAG_DIRECT | KF_FLAG_HASLOCK); 3215 okif->kf_offset = kif->kf_offset; 3216 okif->kf_vnode_type = kif->kf_vnode_type; 3217 okif->kf_sock_domain = kif->kf_sock_domain; 3218 okif->kf_sock_type = kif->kf_sock_type; 3219 okif->kf_sock_protocol = kif->kf_sock_protocol; 3220 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path)); 3221 okif->kf_sa_local = kif->kf_sa_local; 3222 okif->kf_sa_peer = kif->kf_sa_peer; 3223 } 3224 3225 static int 3226 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif, 3227 struct kinfo_ofile *okif, struct filedesc *fdp, struct sysctl_req *req) 3228 { 3229 int error; 3230 3231 vref(vp); 3232 FILEDESC_SUNLOCK(fdp); 3233 export_vnode_to_kinfo(vp, type, 0, kif); 3234 kinfo_to_okinfo(kif, okif); 3235 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 3236 FILEDESC_SLOCK(fdp); 3237 return (error); 3238 } 3239 3240 /* 3241 * Get per-process file descriptors for use by procstat(1), et al. 3242 */ 3243 static int 3244 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3245 { 3246 struct kinfo_ofile *okif; 3247 struct kinfo_file *kif; 3248 struct filedesc *fdp; 3249 struct thread *td; 3250 int error, i, *name; 3251 struct file *fp; 3252 struct proc *p; 3253 3254 td = curthread; 3255 name = (int *)arg1; 3256 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3257 if (error != 0) 3258 return (error); 3259 fdp = fdhold(p); 3260 PROC_UNLOCK(p); 3261 if (fdp == NULL) 3262 return (ENOENT); 3263 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3264 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK); 3265 FILEDESC_SLOCK(fdp); 3266 if (fdp->fd_cdir != NULL) 3267 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3268 okif, fdp, req); 3269 if (fdp->fd_rdir != NULL) 3270 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3271 okif, fdp, req); 3272 if (fdp->fd_jdir != NULL) 3273 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3274 okif, fdp, req); 3275 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3276 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3277 continue; 3278 export_file_to_kinfo(fp, i, NULL, kif, fdp); 3279 FILEDESC_SUNLOCK(fdp); 3280 kinfo_to_okinfo(kif, okif); 3281 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 3282 FILEDESC_SLOCK(fdp); 3283 if (error) 3284 break; 3285 } 3286 FILEDESC_SUNLOCK(fdp); 3287 fddrop(fdp); 3288 free(kif, M_TEMP); 3289 free(okif, M_TEMP); 3290 return (0); 3291 } 3292 3293 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 3294 CTLFLAG_RD||CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 3295 "Process ofiledesc entries"); 3296 #endif /* COMPAT_FREEBSD7 */ 3297 3298 int 3299 vntype_to_kinfo(int vtype) 3300 { 3301 struct { 3302 int vtype; 3303 int kf_vtype; 3304 } vtypes_table[] = { 3305 { VBAD, KF_VTYPE_VBAD }, 3306 { VBLK, KF_VTYPE_VBLK }, 3307 { VCHR, KF_VTYPE_VCHR }, 3308 { VDIR, KF_VTYPE_VDIR }, 3309 { VFIFO, KF_VTYPE_VFIFO }, 3310 { VLNK, KF_VTYPE_VLNK }, 3311 { VNON, KF_VTYPE_VNON }, 3312 { VREG, KF_VTYPE_VREG }, 3313 { VSOCK, KF_VTYPE_VSOCK } 3314 }; 3315 unsigned int i; 3316 3317 /* 3318 * Perform vtype translation. 3319 */ 3320 for (i = 0; i < nitems(vtypes_table); i++) 3321 if (vtypes_table[i].vtype == vtype) 3322 return (vtypes_table[i].kf_vtype); 3323 3324 return (KF_VTYPE_UNKNOWN); 3325 } 3326 3327 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 3328 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 3329 "Process filedesc entries"); 3330 3331 #ifdef DDB 3332 /* 3333 * For the purposes of debugging, generate a human-readable string for the 3334 * file type. 3335 */ 3336 static const char * 3337 file_type_to_name(short type) 3338 { 3339 3340 switch (type) { 3341 case 0: 3342 return ("zero"); 3343 case DTYPE_VNODE: 3344 return ("vnod"); 3345 case DTYPE_SOCKET: 3346 return ("sock"); 3347 case DTYPE_PIPE: 3348 return ("pipe"); 3349 case DTYPE_FIFO: 3350 return ("fifo"); 3351 case DTYPE_KQUEUE: 3352 return ("kque"); 3353 case DTYPE_CRYPTO: 3354 return ("crpt"); 3355 case DTYPE_MQUEUE: 3356 return ("mque"); 3357 case DTYPE_SHM: 3358 return ("shm"); 3359 case DTYPE_SEM: 3360 return ("ksem"); 3361 default: 3362 return ("unkn"); 3363 } 3364 } 3365 3366 /* 3367 * For the purposes of debugging, identify a process (if any, perhaps one of 3368 * many) that references the passed file in its file descriptor array. Return 3369 * NULL if none. 3370 */ 3371 static struct proc * 3372 file_to_first_proc(struct file *fp) 3373 { 3374 struct filedesc *fdp; 3375 struct proc *p; 3376 int n; 3377 3378 FOREACH_PROC_IN_SYSTEM(p) { 3379 if (p->p_state == PRS_NEW) 3380 continue; 3381 fdp = p->p_fd; 3382 if (fdp == NULL) 3383 continue; 3384 for (n = 0; n <= fdp->fd_lastfile; n++) { 3385 if (fp == fdp->fd_ofiles[n].fde_file) 3386 return (p); 3387 } 3388 } 3389 return (NULL); 3390 } 3391 3392 static void 3393 db_print_file(struct file *fp, int header) 3394 { 3395 struct proc *p; 3396 3397 if (header) 3398 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3399 "File", "Type", "Data", "Flag", "GCFl", "Count", 3400 "MCount", "Vnode", "FPID", "FCmd"); 3401 p = file_to_first_proc(fp); 3402 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3403 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3404 0, fp->f_count, 0, fp->f_vnode, 3405 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3406 } 3407 3408 DB_SHOW_COMMAND(file, db_show_file) 3409 { 3410 struct file *fp; 3411 3412 if (!have_addr) { 3413 db_printf("usage: show file <addr>\n"); 3414 return; 3415 } 3416 fp = (struct file *)addr; 3417 db_print_file(fp, 1); 3418 } 3419 3420 DB_SHOW_COMMAND(files, db_show_files) 3421 { 3422 struct filedesc *fdp; 3423 struct file *fp; 3424 struct proc *p; 3425 int header; 3426 int n; 3427 3428 header = 1; 3429 FOREACH_PROC_IN_SYSTEM(p) { 3430 if (p->p_state == PRS_NEW) 3431 continue; 3432 if ((fdp = p->p_fd) == NULL) 3433 continue; 3434 for (n = 0; n <= fdp->fd_lastfile; ++n) { 3435 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3436 continue; 3437 db_print_file(fp, header); 3438 header = 0; 3439 } 3440 } 3441 } 3442 #endif 3443 3444 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3445 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3446 3447 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3448 &maxfiles, 0, "Maximum number of files"); 3449 3450 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3451 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3452 3453 /* ARGSUSED*/ 3454 static void 3455 filelistinit(void *dummy) 3456 { 3457 3458 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3459 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3460 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3461 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3462 } 3463 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3464 3465 /*-------------------------------------------------------------------*/ 3466 3467 static int 3468 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3469 int flags, struct thread *td) 3470 { 3471 3472 return (EBADF); 3473 } 3474 3475 static int 3476 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3477 struct thread *td) 3478 { 3479 3480 return (EINVAL); 3481 } 3482 3483 static int 3484 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3485 struct thread *td) 3486 { 3487 3488 return (EBADF); 3489 } 3490 3491 static int 3492 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3493 struct thread *td) 3494 { 3495 3496 return (0); 3497 } 3498 3499 static int 3500 badfo_kqfilter(struct file *fp, struct knote *kn) 3501 { 3502 3503 return (EBADF); 3504 } 3505 3506 static int 3507 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3508 struct thread *td) 3509 { 3510 3511 return (EBADF); 3512 } 3513 3514 static int 3515 badfo_close(struct file *fp, struct thread *td) 3516 { 3517 3518 return (EBADF); 3519 } 3520 3521 static int 3522 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3523 struct thread *td) 3524 { 3525 3526 return (EBADF); 3527 } 3528 3529 static int 3530 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3531 struct thread *td) 3532 { 3533 3534 return (EBADF); 3535 } 3536 3537 static int 3538 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3539 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3540 int kflags, struct sendfile_sync *sfs, struct thread *td) 3541 { 3542 3543 return (EBADF); 3544 } 3545 3546 static int 3547 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp) 3548 { 3549 3550 return (0); 3551 } 3552 3553 struct fileops badfileops = { 3554 .fo_read = badfo_readwrite, 3555 .fo_write = badfo_readwrite, 3556 .fo_truncate = badfo_truncate, 3557 .fo_ioctl = badfo_ioctl, 3558 .fo_poll = badfo_poll, 3559 .fo_kqfilter = badfo_kqfilter, 3560 .fo_stat = badfo_stat, 3561 .fo_close = badfo_close, 3562 .fo_chmod = badfo_chmod, 3563 .fo_chown = badfo_chown, 3564 .fo_sendfile = badfo_sendfile, 3565 .fo_fill_kinfo = badfo_fill_kinfo, 3566 }; 3567 3568 int 3569 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred, 3570 int flags, struct thread *td) 3571 { 3572 3573 return (EOPNOTSUPP); 3574 } 3575 3576 int 3577 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3578 struct thread *td) 3579 { 3580 3581 return (EINVAL); 3582 } 3583 3584 int 3585 invfo_ioctl(struct file *fp, u_long com, void *data, 3586 struct ucred *active_cred, struct thread *td) 3587 { 3588 3589 return (ENOTTY); 3590 } 3591 3592 int 3593 invfo_poll(struct file *fp, int events, struct ucred *active_cred, 3594 struct thread *td) 3595 { 3596 3597 return (poll_no_poll(events)); 3598 } 3599 3600 int 3601 invfo_kqfilter(struct file *fp, struct knote *kn) 3602 { 3603 3604 return (EINVAL); 3605 } 3606 3607 int 3608 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3609 struct thread *td) 3610 { 3611 3612 return (EINVAL); 3613 } 3614 3615 int 3616 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3617 struct thread *td) 3618 { 3619 3620 return (EINVAL); 3621 } 3622 3623 int 3624 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3625 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3626 int kflags, struct sendfile_sync *sfs, struct thread *td) 3627 { 3628 3629 return (EINVAL); 3630 } 3631 3632 /*-------------------------------------------------------------------*/ 3633 3634 /* 3635 * File Descriptor pseudo-device driver (/dev/fd/). 3636 * 3637 * Opening minor device N dup()s the file (if any) connected to file 3638 * descriptor N belonging to the calling process. Note that this driver 3639 * consists of only the ``open()'' routine, because all subsequent 3640 * references to this file will be direct to the other driver. 3641 * 3642 * XXX: we could give this one a cloning event handler if necessary. 3643 */ 3644 3645 /* ARGSUSED */ 3646 static int 3647 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 3648 { 3649 3650 /* 3651 * XXX Kludge: set curthread->td_dupfd to contain the value of the 3652 * the file descriptor being sought for duplication. The error 3653 * return ensures that the vnode for this device will be released 3654 * by vn_open. Open will detect this special error and take the 3655 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 3656 * will simply report the error. 3657 */ 3658 td->td_dupfd = dev2unit(dev); 3659 return (ENODEV); 3660 } 3661 3662 static struct cdevsw fildesc_cdevsw = { 3663 .d_version = D_VERSION, 3664 .d_open = fdopen, 3665 .d_name = "FD", 3666 }; 3667 3668 static void 3669 fildesc_drvinit(void *unused) 3670 { 3671 struct cdev *dev; 3672 3673 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 3674 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 3675 make_dev_alias(dev, "stdin"); 3676 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 3677 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 3678 make_dev_alias(dev, "stdout"); 3679 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 3680 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 3681 make_dev_alias(dev, "stderr"); 3682 } 3683 3684 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 3685