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/capability.h> 49 #include <sys/conf.h> 50 #include <sys/domain.h> 51 #include <sys/fcntl.h> 52 #include <sys/file.h> 53 #include <sys/filedesc.h> 54 #include <sys/filio.h> 55 #include <sys/jail.h> 56 #include <sys/kernel.h> 57 #include <sys/ksem.h> 58 #include <sys/limits.h> 59 #include <sys/lock.h> 60 #include <sys/malloc.h> 61 #include <sys/mman.h> 62 #include <sys/mount.h> 63 #include <sys/mqueue.h> 64 #include <sys/mutex.h> 65 #include <sys/namei.h> 66 #include <sys/selinfo.h> 67 #include <sys/pipe.h> 68 #include <sys/priv.h> 69 #include <sys/proc.h> 70 #include <sys/procdesc.h> 71 #include <sys/protosw.h> 72 #include <sys/racct.h> 73 #include <sys/resourcevar.h> 74 #include <sys/sbuf.h> 75 #include <sys/signalvar.h> 76 #include <sys/socketvar.h> 77 #include <sys/stat.h> 78 #include <sys/sx.h> 79 #include <sys/syscallsubr.h> 80 #include <sys/sysctl.h> 81 #include <sys/sysproto.h> 82 #include <sys/tty.h> 83 #include <sys/unistd.h> 84 #include <sys/un.h> 85 #include <sys/unpcb.h> 86 #include <sys/user.h> 87 #include <sys/vnode.h> 88 #ifdef KTRACE 89 #include <sys/ktrace.h> 90 #endif 91 92 #include <net/vnet.h> 93 94 #include <netinet/in.h> 95 #include <netinet/in_pcb.h> 96 97 #include <security/audit/audit.h> 98 99 #include <vm/uma.h> 100 #include <vm/vm.h> 101 102 #include <ddb/ddb.h> 103 104 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 105 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 106 "file desc to leader structures"); 107 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 108 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 109 110 MALLOC_DECLARE(M_FADVISE); 111 112 static uma_zone_t file_zone; 113 114 void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value); 115 116 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 117 struct thread *td, int holdleaders); 118 static int fd_first_free(struct filedesc *fdp, int low, int size); 119 static int fd_last_used(struct filedesc *fdp, int size); 120 static void fdgrowtable(struct filedesc *fdp, int nfd); 121 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 122 static void fdunused(struct filedesc *fdp, int fd); 123 static void fdused(struct filedesc *fdp, int fd); 124 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); 125 static int fill_procdesc_info(struct procdesc *pdp, 126 struct kinfo_file *kif); 127 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif); 128 static int fill_sem_info(struct file *fp, struct kinfo_file *kif); 129 static int fill_shm_info(struct file *fp, struct kinfo_file *kif); 130 static int fill_socket_info(struct socket *so, struct kinfo_file *kif); 131 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); 132 static int getmaxfd(struct proc *p); 133 134 /* 135 * Each process has: 136 * 137 * - An array of open file descriptors (fd_ofiles) 138 * - An array of file flags (fd_ofileflags) 139 * - A bitmap recording which descriptors are in use (fd_map) 140 * 141 * A process starts out with NDFILE descriptors. The value of NDFILE has 142 * been selected based the historical limit of 20 open files, and an 143 * assumption that the majority of processes, especially short-lived 144 * processes like shells, will never need more. 145 * 146 * If this initial allocation is exhausted, a larger descriptor table and 147 * map are allocated dynamically, and the pointers in the process's struct 148 * filedesc are updated to point to those. This is repeated every time 149 * the process runs out of file descriptors (provided it hasn't hit its 150 * resource limit). 151 * 152 * Since threads may hold references to individual descriptor table 153 * entries, the tables are never freed. Instead, they are placed on a 154 * linked list and freed only when the struct filedesc is released. 155 */ 156 #define NDFILE 20 157 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 158 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 159 #define NDSLOT(x) ((x) / NDENTRIES) 160 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 161 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 162 163 /* 164 * SLIST entry used to keep track of ofiles which must be reclaimed when 165 * the process exits. 166 */ 167 struct freetable { 168 struct filedescent *ft_table; 169 SLIST_ENTRY(freetable) ft_next; 170 }; 171 172 /* 173 * Initial allocation: a filedesc structure + the head of SLIST used to 174 * keep track of old ofiles + enough space for NDFILE descriptors. 175 */ 176 struct filedesc0 { 177 struct filedesc fd_fd; 178 SLIST_HEAD(, freetable) fd_free; 179 struct filedescent fd_dfiles[NDFILE]; 180 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 181 }; 182 183 /* 184 * Descriptor management. 185 */ 186 volatile int openfiles; /* actual number of open files */ 187 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 188 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 189 190 /* A mutex to protect the association between a proc and filedesc. */ 191 static struct mtx fdesc_mtx; 192 193 /* 194 * If low >= size, just return low. Otherwise find the first zero bit in the 195 * given bitmap, starting at low and not exceeding size - 1. Return size if 196 * not found. 197 */ 198 static int 199 fd_first_free(struct filedesc *fdp, int low, int size) 200 { 201 NDSLOTTYPE *map = fdp->fd_map; 202 NDSLOTTYPE mask; 203 int off, maxoff; 204 205 if (low >= size) 206 return (low); 207 208 off = NDSLOT(low); 209 if (low % NDENTRIES) { 210 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 211 if ((mask &= ~map[off]) != 0UL) 212 return (off * NDENTRIES + ffsl(mask) - 1); 213 ++off; 214 } 215 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 216 if (map[off] != ~0UL) 217 return (off * NDENTRIES + ffsl(~map[off]) - 1); 218 return (size); 219 } 220 221 /* 222 * Find the highest non-zero bit in the given bitmap, starting at 0 and 223 * not exceeding size - 1. Return -1 if not found. 224 */ 225 static int 226 fd_last_used(struct filedesc *fdp, int size) 227 { 228 NDSLOTTYPE *map = fdp->fd_map; 229 NDSLOTTYPE mask; 230 int off, minoff; 231 232 off = NDSLOT(size); 233 if (size % NDENTRIES) { 234 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 235 if ((mask &= map[off]) != 0) 236 return (off * NDENTRIES + flsl(mask) - 1); 237 --off; 238 } 239 for (minoff = NDSLOT(0); off >= minoff; --off) 240 if (map[off] != 0) 241 return (off * NDENTRIES + flsl(map[off]) - 1); 242 return (-1); 243 } 244 245 static int 246 fdisused(struct filedesc *fdp, int fd) 247 { 248 249 FILEDESC_LOCK_ASSERT(fdp); 250 251 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 252 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 253 254 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 255 } 256 257 /* 258 * Mark a file descriptor as used. 259 */ 260 static void 261 fdused(struct filedesc *fdp, int fd) 262 { 263 264 FILEDESC_XLOCK_ASSERT(fdp); 265 266 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 267 268 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 269 if (fd > fdp->fd_lastfile) 270 fdp->fd_lastfile = fd; 271 if (fd == fdp->fd_freefile) 272 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 273 } 274 275 /* 276 * Mark a file descriptor as unused. 277 */ 278 static void 279 fdunused(struct filedesc *fdp, int fd) 280 { 281 282 FILEDESC_XLOCK_ASSERT(fdp); 283 284 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 285 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 286 ("fd=%d is still in use", fd)); 287 288 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 289 if (fd < fdp->fd_freefile) 290 fdp->fd_freefile = fd; 291 if (fd == fdp->fd_lastfile) 292 fdp->fd_lastfile = fd_last_used(fdp, fd); 293 } 294 295 /* 296 * Free a file descriptor. 297 */ 298 static inline void 299 fdfree(struct filedesc *fdp, int fd) 300 { 301 struct filedescent *fde; 302 303 fde = &fdp->fd_ofiles[fd]; 304 filecaps_free(&fde->fde_caps); 305 bzero(fde, sizeof(*fde)); 306 fdunused(fdp, fd); 307 } 308 309 /* 310 * System calls on descriptors. 311 */ 312 #ifndef _SYS_SYSPROTO_H_ 313 struct getdtablesize_args { 314 int dummy; 315 }; 316 #endif 317 /* ARGSUSED */ 318 int 319 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 320 { 321 struct proc *p = td->td_proc; 322 uint64_t lim; 323 324 PROC_LOCK(p); 325 td->td_retval[0] = 326 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 327 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 328 PROC_UNLOCK(p); 329 if (lim < td->td_retval[0]) 330 td->td_retval[0] = lim; 331 return (0); 332 } 333 334 /* 335 * Duplicate a file descriptor to a particular value. 336 * 337 * Note: keep in mind that a potential race condition exists when closing 338 * descriptors from a shared descriptor table (via rfork). 339 */ 340 #ifndef _SYS_SYSPROTO_H_ 341 struct dup2_args { 342 u_int from; 343 u_int to; 344 }; 345 #endif 346 /* ARGSUSED */ 347 int 348 sys_dup2(struct thread *td, struct dup2_args *uap) 349 { 350 351 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 352 td->td_retval)); 353 } 354 355 /* 356 * Duplicate a file descriptor. 357 */ 358 #ifndef _SYS_SYSPROTO_H_ 359 struct dup_args { 360 u_int fd; 361 }; 362 #endif 363 /* ARGSUSED */ 364 int 365 sys_dup(struct thread *td, struct dup_args *uap) 366 { 367 368 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 369 } 370 371 /* 372 * The file control system call. 373 */ 374 #ifndef _SYS_SYSPROTO_H_ 375 struct fcntl_args { 376 int fd; 377 int cmd; 378 long arg; 379 }; 380 #endif 381 /* ARGSUSED */ 382 int 383 sys_fcntl(struct thread *td, struct fcntl_args *uap) 384 { 385 struct flock fl; 386 struct __oflock ofl; 387 intptr_t arg; 388 int error; 389 int cmd; 390 391 error = 0; 392 cmd = uap->cmd; 393 switch (uap->cmd) { 394 case F_OGETLK: 395 case F_OSETLK: 396 case F_OSETLKW: 397 /* 398 * Convert old flock structure to new. 399 */ 400 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 401 fl.l_start = ofl.l_start; 402 fl.l_len = ofl.l_len; 403 fl.l_pid = ofl.l_pid; 404 fl.l_type = ofl.l_type; 405 fl.l_whence = ofl.l_whence; 406 fl.l_sysid = 0; 407 408 switch (uap->cmd) { 409 case F_OGETLK: 410 cmd = F_GETLK; 411 break; 412 case F_OSETLK: 413 cmd = F_SETLK; 414 break; 415 case F_OSETLKW: 416 cmd = F_SETLKW; 417 break; 418 } 419 arg = (intptr_t)&fl; 420 break; 421 case F_GETLK: 422 case F_SETLK: 423 case F_SETLKW: 424 case F_SETLK_REMOTE: 425 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 426 arg = (intptr_t)&fl; 427 break; 428 default: 429 arg = uap->arg; 430 break; 431 } 432 if (error) 433 return (error); 434 error = kern_fcntl(td, uap->fd, cmd, arg); 435 if (error) 436 return (error); 437 if (uap->cmd == F_OGETLK) { 438 ofl.l_start = fl.l_start; 439 ofl.l_len = fl.l_len; 440 ofl.l_pid = fl.l_pid; 441 ofl.l_type = fl.l_type; 442 ofl.l_whence = fl.l_whence; 443 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 444 } else if (uap->cmd == F_GETLK) { 445 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 446 } 447 return (error); 448 } 449 450 int 451 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 452 { 453 struct filedesc *fdp; 454 struct flock *flp; 455 struct file *fp, *fp2; 456 struct filedescent *fde; 457 struct proc *p; 458 struct vnode *vp; 459 cap_rights_t rights; 460 int error, flg, tmp; 461 u_int old, new; 462 uint64_t bsize; 463 off_t foffset; 464 465 error = 0; 466 flg = F_POSIX; 467 p = td->td_proc; 468 fdp = p->p_fd; 469 470 switch (cmd) { 471 case F_DUPFD: 472 tmp = arg; 473 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 474 break; 475 476 case F_DUPFD_CLOEXEC: 477 tmp = arg; 478 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 479 td->td_retval); 480 break; 481 482 case F_DUP2FD: 483 tmp = arg; 484 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 485 break; 486 487 case F_DUP2FD_CLOEXEC: 488 tmp = arg; 489 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 490 td->td_retval); 491 break; 492 493 case F_GETFD: 494 FILEDESC_SLOCK(fdp); 495 if ((fp = fget_locked(fdp, fd)) == NULL) { 496 FILEDESC_SUNLOCK(fdp); 497 error = EBADF; 498 break; 499 } 500 fde = &fdp->fd_ofiles[fd]; 501 td->td_retval[0] = 502 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 503 FILEDESC_SUNLOCK(fdp); 504 break; 505 506 case F_SETFD: 507 FILEDESC_XLOCK(fdp); 508 if ((fp = fget_locked(fdp, fd)) == NULL) { 509 FILEDESC_XUNLOCK(fdp); 510 error = EBADF; 511 break; 512 } 513 fde = &fdp->fd_ofiles[fd]; 514 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 515 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 516 FILEDESC_XUNLOCK(fdp); 517 break; 518 519 case F_GETFL: 520 error = fget_unlocked(fdp, fd, 521 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp, NULL); 522 if (error != 0) 523 break; 524 td->td_retval[0] = OFLAGS(fp->f_flag); 525 fdrop(fp, td); 526 break; 527 528 case F_SETFL: 529 error = fget_unlocked(fdp, fd, 530 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp, NULL); 531 if (error != 0) 532 break; 533 do { 534 tmp = flg = fp->f_flag; 535 tmp &= ~FCNTLFLAGS; 536 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 537 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 538 tmp = fp->f_flag & FNONBLOCK; 539 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 540 if (error != 0) { 541 fdrop(fp, td); 542 break; 543 } 544 tmp = fp->f_flag & FASYNC; 545 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 546 if (error == 0) { 547 fdrop(fp, td); 548 break; 549 } 550 atomic_clear_int(&fp->f_flag, FNONBLOCK); 551 tmp = 0; 552 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 553 fdrop(fp, td); 554 break; 555 556 case F_GETOWN: 557 error = fget_unlocked(fdp, fd, 558 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp, NULL); 559 if (error != 0) 560 break; 561 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 562 if (error == 0) 563 td->td_retval[0] = tmp; 564 fdrop(fp, td); 565 break; 566 567 case F_SETOWN: 568 error = fget_unlocked(fdp, fd, 569 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp, NULL); 570 if (error != 0) 571 break; 572 tmp = arg; 573 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 574 fdrop(fp, td); 575 break; 576 577 case F_SETLK_REMOTE: 578 error = priv_check(td, PRIV_NFS_LOCKD); 579 if (error) 580 return (error); 581 flg = F_REMOTE; 582 goto do_setlk; 583 584 case F_SETLKW: 585 flg |= F_WAIT; 586 /* FALLTHROUGH F_SETLK */ 587 588 case F_SETLK: 589 do_setlk: 590 cap_rights_init(&rights, CAP_FLOCK); 591 error = fget_unlocked(fdp, fd, &rights, 0, &fp, NULL); 592 if (error != 0) 593 break; 594 if (fp->f_type != DTYPE_VNODE) { 595 error = EBADF; 596 fdrop(fp, td); 597 break; 598 } 599 600 flp = (struct flock *)arg; 601 if (flp->l_whence == SEEK_CUR) { 602 foffset = foffset_get(fp); 603 if (foffset < 0 || 604 (flp->l_start > 0 && 605 foffset > OFF_MAX - flp->l_start)) { 606 FILEDESC_SUNLOCK(fdp); 607 error = EOVERFLOW; 608 fdrop(fp, td); 609 break; 610 } 611 flp->l_start += foffset; 612 } 613 614 vp = fp->f_vnode; 615 switch (flp->l_type) { 616 case F_RDLCK: 617 if ((fp->f_flag & FREAD) == 0) { 618 error = EBADF; 619 break; 620 } 621 PROC_LOCK(p->p_leader); 622 p->p_leader->p_flag |= P_ADVLOCK; 623 PROC_UNLOCK(p->p_leader); 624 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 625 flp, flg); 626 break; 627 case F_WRLCK: 628 if ((fp->f_flag & FWRITE) == 0) { 629 error = EBADF; 630 break; 631 } 632 PROC_LOCK(p->p_leader); 633 p->p_leader->p_flag |= P_ADVLOCK; 634 PROC_UNLOCK(p->p_leader); 635 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 636 flp, flg); 637 break; 638 case F_UNLCK: 639 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 640 flp, flg); 641 break; 642 case F_UNLCKSYS: 643 /* 644 * Temporary api for testing remote lock 645 * infrastructure. 646 */ 647 if (flg != F_REMOTE) { 648 error = EINVAL; 649 break; 650 } 651 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 652 F_UNLCKSYS, flp, flg); 653 break; 654 default: 655 error = EINVAL; 656 break; 657 } 658 if (error != 0 || flp->l_type == F_UNLCK || 659 flp->l_type == F_UNLCKSYS) { 660 fdrop(fp, td); 661 break; 662 } 663 664 /* 665 * Check for a race with close. 666 * 667 * The vnode is now advisory locked (or unlocked, but this case 668 * is not really important) as the caller requested. 669 * We had to drop the filedesc lock, so we need to recheck if 670 * the descriptor is still valid, because if it was closed 671 * in the meantime we need to remove advisory lock from the 672 * vnode - close on any descriptor leading to an advisory 673 * locked vnode, removes that lock. 674 * We will return 0 on purpose in that case, as the result of 675 * successful advisory lock might have been externally visible 676 * already. This is fine - effectively we pretend to the caller 677 * that the closing thread was a bit slower and that the 678 * advisory lock succeeded before the close. 679 */ 680 error = fget_unlocked(fdp, fd, &rights, 0, &fp2, NULL); 681 if (error != 0) { 682 fdrop(fp, td); 683 break; 684 } 685 if (fp != fp2) { 686 flp->l_whence = SEEK_SET; 687 flp->l_start = 0; 688 flp->l_len = 0; 689 flp->l_type = F_UNLCK; 690 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 691 F_UNLCK, flp, F_POSIX); 692 } 693 fdrop(fp, td); 694 fdrop(fp2, td); 695 break; 696 697 case F_GETLK: 698 error = fget_unlocked(fdp, fd, 699 cap_rights_init(&rights, CAP_FLOCK), 0, &fp, NULL); 700 if (error != 0) 701 break; 702 if (fp->f_type != DTYPE_VNODE) { 703 error = EBADF; 704 fdrop(fp, td); 705 break; 706 } 707 flp = (struct flock *)arg; 708 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 709 flp->l_type != F_UNLCK) { 710 error = EINVAL; 711 fdrop(fp, td); 712 break; 713 } 714 if (flp->l_whence == SEEK_CUR) { 715 foffset = foffset_get(fp); 716 if ((flp->l_start > 0 && 717 foffset > OFF_MAX - flp->l_start) || 718 (flp->l_start < 0 && 719 foffset < OFF_MIN - flp->l_start)) { 720 FILEDESC_SUNLOCK(fdp); 721 error = EOVERFLOW; 722 fdrop(fp, td); 723 break; 724 } 725 flp->l_start += foffset; 726 } 727 vp = fp->f_vnode; 728 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 729 F_POSIX); 730 fdrop(fp, td); 731 break; 732 733 case F_RDAHEAD: 734 arg = arg ? 128 * 1024: 0; 735 /* FALLTHROUGH */ 736 case F_READAHEAD: 737 error = fget_unlocked(fdp, fd, NULL, 0, &fp, NULL); 738 if (error != 0) 739 break; 740 if (fp->f_type != DTYPE_VNODE) { 741 fdrop(fp, td); 742 error = EBADF; 743 break; 744 } 745 if (arg >= 0) { 746 vp = fp->f_vnode; 747 error = vn_lock(vp, LK_SHARED); 748 if (error != 0) { 749 fdrop(fp, td); 750 break; 751 } 752 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 753 VOP_UNLOCK(vp, 0); 754 fp->f_seqcount = (arg + bsize - 1) / bsize; 755 do { 756 new = old = fp->f_flag; 757 new |= FRDAHEAD; 758 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 759 } else { 760 do { 761 new = old = fp->f_flag; 762 new &= ~FRDAHEAD; 763 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 764 } 765 fdrop(fp, td); 766 break; 767 768 default: 769 error = EINVAL; 770 break; 771 } 772 return (error); 773 } 774 775 static int 776 getmaxfd(struct proc *p) 777 { 778 int maxfd; 779 780 PROC_LOCK(p); 781 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 782 PROC_UNLOCK(p); 783 784 return (maxfd); 785 } 786 787 /* 788 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 789 */ 790 int 791 do_dup(struct thread *td, int flags, int old, int new, 792 register_t *retval) 793 { 794 struct filedesc *fdp; 795 struct filedescent *oldfde, *newfde; 796 struct proc *p; 797 struct file *fp; 798 struct file *delfp; 799 int error, maxfd; 800 801 p = td->td_proc; 802 fdp = p->p_fd; 803 804 /* 805 * Verify we have a valid descriptor to dup from and possibly to 806 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 807 * return EINVAL when the new descriptor is out of bounds. 808 */ 809 if (old < 0) 810 return (EBADF); 811 if (new < 0) 812 return (flags & DUP_FCNTL ? EINVAL : EBADF); 813 maxfd = getmaxfd(p); 814 if (new >= maxfd) 815 return (flags & DUP_FCNTL ? EINVAL : EBADF); 816 817 FILEDESC_XLOCK(fdp); 818 if (fget_locked(fdp, old) == NULL) { 819 FILEDESC_XUNLOCK(fdp); 820 return (EBADF); 821 } 822 oldfde = &fdp->fd_ofiles[old]; 823 if (flags & DUP_FIXED && old == new) { 824 *retval = new; 825 if (flags & DUP_CLOEXEC) 826 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 827 FILEDESC_XUNLOCK(fdp); 828 return (0); 829 } 830 fp = oldfde->fde_file; 831 fhold(fp); 832 833 /* 834 * If the caller specified a file descriptor, make sure the file 835 * table is large enough to hold it, and grab it. Otherwise, just 836 * allocate a new descriptor the usual way. 837 */ 838 if (flags & DUP_FIXED) { 839 if (new >= fdp->fd_nfiles) { 840 /* 841 * The resource limits are here instead of e.g. 842 * fdalloc(), because the file descriptor table may be 843 * shared between processes, so we can't really use 844 * racct_add()/racct_sub(). Instead of counting the 845 * number of actually allocated descriptors, just put 846 * the limit on the size of the file descriptor table. 847 */ 848 #ifdef RACCT 849 PROC_LOCK(p); 850 error = racct_set(p, RACCT_NOFILE, new + 1); 851 PROC_UNLOCK(p); 852 if (error != 0) { 853 FILEDESC_XUNLOCK(fdp); 854 fdrop(fp, td); 855 return (EMFILE); 856 } 857 #endif 858 fdgrowtable_exp(fdp, new + 1); 859 oldfde = &fdp->fd_ofiles[old]; 860 } 861 newfde = &fdp->fd_ofiles[new]; 862 if (newfde->fde_file == NULL) 863 fdused(fdp, new); 864 } else { 865 if ((error = fdalloc(td, new, &new)) != 0) { 866 FILEDESC_XUNLOCK(fdp); 867 fdrop(fp, td); 868 return (error); 869 } 870 newfde = &fdp->fd_ofiles[new]; 871 } 872 873 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 874 KASSERT(old != new, ("new fd is same as old")); 875 876 delfp = newfde->fde_file; 877 878 /* 879 * Duplicate the source descriptor. 880 */ 881 *newfde = *oldfde; 882 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 883 if ((flags & DUP_CLOEXEC) != 0) 884 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 885 else 886 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 887 if (new > fdp->fd_lastfile) 888 fdp->fd_lastfile = new; 889 *retval = new; 890 891 if (delfp != NULL) { 892 (void) closefp(fdp, new, delfp, td, 1); 893 /* closefp() drops the FILEDESC lock for us. */ 894 } else { 895 FILEDESC_XUNLOCK(fdp); 896 } 897 898 return (0); 899 } 900 901 /* 902 * If sigio is on the list associated with a process or process group, 903 * disable signalling from the device, remove sigio from the list and 904 * free sigio. 905 */ 906 void 907 funsetown(struct sigio **sigiop) 908 { 909 struct sigio *sigio; 910 911 SIGIO_LOCK(); 912 sigio = *sigiop; 913 if (sigio == NULL) { 914 SIGIO_UNLOCK(); 915 return; 916 } 917 *(sigio->sio_myref) = NULL; 918 if ((sigio)->sio_pgid < 0) { 919 struct pgrp *pg = (sigio)->sio_pgrp; 920 PGRP_LOCK(pg); 921 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 922 sigio, sio_pgsigio); 923 PGRP_UNLOCK(pg); 924 } else { 925 struct proc *p = (sigio)->sio_proc; 926 PROC_LOCK(p); 927 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 928 sigio, sio_pgsigio); 929 PROC_UNLOCK(p); 930 } 931 SIGIO_UNLOCK(); 932 crfree(sigio->sio_ucred); 933 free(sigio, M_SIGIO); 934 } 935 936 /* 937 * Free a list of sigio structures. 938 * We only need to lock the SIGIO_LOCK because we have made ourselves 939 * inaccessible to callers of fsetown and therefore do not need to lock 940 * the proc or pgrp struct for the list manipulation. 941 */ 942 void 943 funsetownlst(struct sigiolst *sigiolst) 944 { 945 struct proc *p; 946 struct pgrp *pg; 947 struct sigio *sigio; 948 949 sigio = SLIST_FIRST(sigiolst); 950 if (sigio == NULL) 951 return; 952 p = NULL; 953 pg = NULL; 954 955 /* 956 * Every entry of the list should belong 957 * to a single proc or pgrp. 958 */ 959 if (sigio->sio_pgid < 0) { 960 pg = sigio->sio_pgrp; 961 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 962 } else /* if (sigio->sio_pgid > 0) */ { 963 p = sigio->sio_proc; 964 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 965 } 966 967 SIGIO_LOCK(); 968 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 969 *(sigio->sio_myref) = NULL; 970 if (pg != NULL) { 971 KASSERT(sigio->sio_pgid < 0, 972 ("Proc sigio in pgrp sigio list")); 973 KASSERT(sigio->sio_pgrp == pg, 974 ("Bogus pgrp in sigio list")); 975 PGRP_LOCK(pg); 976 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 977 sio_pgsigio); 978 PGRP_UNLOCK(pg); 979 } else /* if (p != NULL) */ { 980 KASSERT(sigio->sio_pgid > 0, 981 ("Pgrp sigio in proc sigio list")); 982 KASSERT(sigio->sio_proc == p, 983 ("Bogus proc in sigio list")); 984 PROC_LOCK(p); 985 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 986 sio_pgsigio); 987 PROC_UNLOCK(p); 988 } 989 SIGIO_UNLOCK(); 990 crfree(sigio->sio_ucred); 991 free(sigio, M_SIGIO); 992 SIGIO_LOCK(); 993 } 994 SIGIO_UNLOCK(); 995 } 996 997 /* 998 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 999 * 1000 * After permission checking, add a sigio structure to the sigio list for 1001 * the process or process group. 1002 */ 1003 int 1004 fsetown(pid_t pgid, struct sigio **sigiop) 1005 { 1006 struct proc *proc; 1007 struct pgrp *pgrp; 1008 struct sigio *sigio; 1009 int ret; 1010 1011 if (pgid == 0) { 1012 funsetown(sigiop); 1013 return (0); 1014 } 1015 1016 ret = 0; 1017 1018 /* Allocate and fill in the new sigio out of locks. */ 1019 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1020 sigio->sio_pgid = pgid; 1021 sigio->sio_ucred = crhold(curthread->td_ucred); 1022 sigio->sio_myref = sigiop; 1023 1024 sx_slock(&proctree_lock); 1025 if (pgid > 0) { 1026 proc = pfind(pgid); 1027 if (proc == NULL) { 1028 ret = ESRCH; 1029 goto fail; 1030 } 1031 1032 /* 1033 * Policy - Don't allow a process to FSETOWN a process 1034 * in another session. 1035 * 1036 * Remove this test to allow maximum flexibility or 1037 * restrict FSETOWN to the current process or process 1038 * group for maximum safety. 1039 */ 1040 PROC_UNLOCK(proc); 1041 if (proc->p_session != curthread->td_proc->p_session) { 1042 ret = EPERM; 1043 goto fail; 1044 } 1045 1046 pgrp = NULL; 1047 } else /* if (pgid < 0) */ { 1048 pgrp = pgfind(-pgid); 1049 if (pgrp == NULL) { 1050 ret = ESRCH; 1051 goto fail; 1052 } 1053 PGRP_UNLOCK(pgrp); 1054 1055 /* 1056 * Policy - Don't allow a process to FSETOWN a process 1057 * in another session. 1058 * 1059 * Remove this test to allow maximum flexibility or 1060 * restrict FSETOWN to the current process or process 1061 * group for maximum safety. 1062 */ 1063 if (pgrp->pg_session != curthread->td_proc->p_session) { 1064 ret = EPERM; 1065 goto fail; 1066 } 1067 1068 proc = NULL; 1069 } 1070 funsetown(sigiop); 1071 if (pgid > 0) { 1072 PROC_LOCK(proc); 1073 /* 1074 * Since funsetownlst() is called without the proctree 1075 * locked, we need to check for P_WEXIT. 1076 * XXX: is ESRCH correct? 1077 */ 1078 if ((proc->p_flag & P_WEXIT) != 0) { 1079 PROC_UNLOCK(proc); 1080 ret = ESRCH; 1081 goto fail; 1082 } 1083 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1084 sigio->sio_proc = proc; 1085 PROC_UNLOCK(proc); 1086 } else { 1087 PGRP_LOCK(pgrp); 1088 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1089 sigio->sio_pgrp = pgrp; 1090 PGRP_UNLOCK(pgrp); 1091 } 1092 sx_sunlock(&proctree_lock); 1093 SIGIO_LOCK(); 1094 *sigiop = sigio; 1095 SIGIO_UNLOCK(); 1096 return (0); 1097 1098 fail: 1099 sx_sunlock(&proctree_lock); 1100 crfree(sigio->sio_ucred); 1101 free(sigio, M_SIGIO); 1102 return (ret); 1103 } 1104 1105 /* 1106 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1107 */ 1108 pid_t 1109 fgetown(sigiop) 1110 struct sigio **sigiop; 1111 { 1112 pid_t pgid; 1113 1114 SIGIO_LOCK(); 1115 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1116 SIGIO_UNLOCK(); 1117 return (pgid); 1118 } 1119 1120 /* 1121 * Function drops the filedesc lock on return. 1122 */ 1123 static int 1124 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1125 int holdleaders) 1126 { 1127 int error; 1128 1129 FILEDESC_XLOCK_ASSERT(fdp); 1130 1131 if (holdleaders) { 1132 if (td->td_proc->p_fdtol != NULL) { 1133 /* 1134 * Ask fdfree() to sleep to ensure that all relevant 1135 * process leaders can be traversed in closef(). 1136 */ 1137 fdp->fd_holdleaderscount++; 1138 } else { 1139 holdleaders = 0; 1140 } 1141 } 1142 1143 /* 1144 * We now hold the fp reference that used to be owned by the 1145 * descriptor array. We have to unlock the FILEDESC *AFTER* 1146 * knote_fdclose to prevent a race of the fd getting opened, a knote 1147 * added, and deleteing a knote for the new fd. 1148 */ 1149 knote_fdclose(td, fd); 1150 1151 /* 1152 * We need to notify mqueue if the object is of type mqueue. 1153 */ 1154 if (fp->f_type == DTYPE_MQUEUE) 1155 mq_fdclose(td, fd, fp); 1156 FILEDESC_XUNLOCK(fdp); 1157 1158 error = closef(fp, td); 1159 if (holdleaders) { 1160 FILEDESC_XLOCK(fdp); 1161 fdp->fd_holdleaderscount--; 1162 if (fdp->fd_holdleaderscount == 0 && 1163 fdp->fd_holdleaderswakeup != 0) { 1164 fdp->fd_holdleaderswakeup = 0; 1165 wakeup(&fdp->fd_holdleaderscount); 1166 } 1167 FILEDESC_XUNLOCK(fdp); 1168 } 1169 return (error); 1170 } 1171 1172 /* 1173 * Close a file descriptor. 1174 */ 1175 #ifndef _SYS_SYSPROTO_H_ 1176 struct close_args { 1177 int fd; 1178 }; 1179 #endif 1180 /* ARGSUSED */ 1181 int 1182 sys_close(td, uap) 1183 struct thread *td; 1184 struct close_args *uap; 1185 { 1186 1187 return (kern_close(td, uap->fd)); 1188 } 1189 1190 int 1191 kern_close(td, fd) 1192 struct thread *td; 1193 int fd; 1194 { 1195 struct filedesc *fdp; 1196 struct file *fp; 1197 1198 fdp = td->td_proc->p_fd; 1199 1200 AUDIT_SYSCLOSE(td, fd); 1201 1202 FILEDESC_XLOCK(fdp); 1203 if ((fp = fget_locked(fdp, fd)) == NULL) { 1204 FILEDESC_XUNLOCK(fdp); 1205 return (EBADF); 1206 } 1207 fdfree(fdp, fd); 1208 1209 /* closefp() drops the FILEDESC lock for us. */ 1210 return (closefp(fdp, fd, fp, td, 1)); 1211 } 1212 1213 /* 1214 * Close open file descriptors. 1215 */ 1216 #ifndef _SYS_SYSPROTO_H_ 1217 struct closefrom_args { 1218 int lowfd; 1219 }; 1220 #endif 1221 /* ARGSUSED */ 1222 int 1223 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1224 { 1225 struct filedesc *fdp; 1226 int fd; 1227 1228 fdp = td->td_proc->p_fd; 1229 AUDIT_ARG_FD(uap->lowfd); 1230 1231 /* 1232 * Treat negative starting file descriptor values identical to 1233 * closefrom(0) which closes all files. 1234 */ 1235 if (uap->lowfd < 0) 1236 uap->lowfd = 0; 1237 FILEDESC_SLOCK(fdp); 1238 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) { 1239 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1240 FILEDESC_SUNLOCK(fdp); 1241 (void)kern_close(td, fd); 1242 FILEDESC_SLOCK(fdp); 1243 } 1244 } 1245 FILEDESC_SUNLOCK(fdp); 1246 return (0); 1247 } 1248 1249 #if defined(COMPAT_43) 1250 /* 1251 * Return status information about a file descriptor. 1252 */ 1253 #ifndef _SYS_SYSPROTO_H_ 1254 struct ofstat_args { 1255 int fd; 1256 struct ostat *sb; 1257 }; 1258 #endif 1259 /* ARGSUSED */ 1260 int 1261 ofstat(struct thread *td, struct ofstat_args *uap) 1262 { 1263 struct ostat oub; 1264 struct stat ub; 1265 int error; 1266 1267 error = kern_fstat(td, uap->fd, &ub); 1268 if (error == 0) { 1269 cvtstat(&ub, &oub); 1270 error = copyout(&oub, uap->sb, sizeof(oub)); 1271 } 1272 return (error); 1273 } 1274 #endif /* COMPAT_43 */ 1275 1276 /* 1277 * Return status information about a file descriptor. 1278 */ 1279 #ifndef _SYS_SYSPROTO_H_ 1280 struct fstat_args { 1281 int fd; 1282 struct stat *sb; 1283 }; 1284 #endif 1285 /* ARGSUSED */ 1286 int 1287 sys_fstat(struct thread *td, struct fstat_args *uap) 1288 { 1289 struct stat ub; 1290 int error; 1291 1292 error = kern_fstat(td, uap->fd, &ub); 1293 if (error == 0) 1294 error = copyout(&ub, uap->sb, sizeof(ub)); 1295 return (error); 1296 } 1297 1298 int 1299 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1300 { 1301 struct file *fp; 1302 cap_rights_t rights; 1303 int error; 1304 1305 AUDIT_ARG_FD(fd); 1306 1307 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1308 if (error != 0) 1309 return (error); 1310 1311 AUDIT_ARG_FILE(td->td_proc, fp); 1312 1313 error = fo_stat(fp, sbp, td->td_ucred, td); 1314 fdrop(fp, td); 1315 #ifdef KTRACE 1316 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1317 ktrstat(sbp); 1318 #endif 1319 return (error); 1320 } 1321 1322 /* 1323 * Return status information about a file descriptor. 1324 */ 1325 #ifndef _SYS_SYSPROTO_H_ 1326 struct nfstat_args { 1327 int fd; 1328 struct nstat *sb; 1329 }; 1330 #endif 1331 /* ARGSUSED */ 1332 int 1333 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1334 { 1335 struct nstat nub; 1336 struct stat ub; 1337 int error; 1338 1339 error = kern_fstat(td, uap->fd, &ub); 1340 if (error == 0) { 1341 cvtnstat(&ub, &nub); 1342 error = copyout(&nub, uap->sb, sizeof(nub)); 1343 } 1344 return (error); 1345 } 1346 1347 /* 1348 * Return pathconf information about a file descriptor. 1349 */ 1350 #ifndef _SYS_SYSPROTO_H_ 1351 struct fpathconf_args { 1352 int fd; 1353 int name; 1354 }; 1355 #endif 1356 /* ARGSUSED */ 1357 int 1358 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1359 { 1360 struct file *fp; 1361 struct vnode *vp; 1362 cap_rights_t rights; 1363 int error; 1364 1365 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1366 if (error != 0) 1367 return (error); 1368 1369 /* If asynchronous I/O is available, it works for all descriptors. */ 1370 if (uap->name == _PC_ASYNC_IO) { 1371 td->td_retval[0] = async_io_version; 1372 goto out; 1373 } 1374 vp = fp->f_vnode; 1375 if (vp != NULL) { 1376 vn_lock(vp, LK_SHARED | LK_RETRY); 1377 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1378 VOP_UNLOCK(vp, 0); 1379 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1380 if (uap->name != _PC_PIPE_BUF) { 1381 error = EINVAL; 1382 } else { 1383 td->td_retval[0] = PIPE_BUF; 1384 error = 0; 1385 } 1386 } else { 1387 error = EOPNOTSUPP; 1388 } 1389 out: 1390 fdrop(fp, td); 1391 return (error); 1392 } 1393 1394 /* 1395 * Initialize filecaps structure. 1396 */ 1397 void 1398 filecaps_init(struct filecaps *fcaps) 1399 { 1400 1401 bzero(fcaps, sizeof(*fcaps)); 1402 fcaps->fc_nioctls = -1; 1403 } 1404 1405 /* 1406 * Copy filecaps structure allocating memory for ioctls array if needed. 1407 */ 1408 void 1409 filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1410 { 1411 size_t size; 1412 1413 *dst = *src; 1414 if (src->fc_ioctls != NULL) { 1415 KASSERT(src->fc_nioctls > 0, 1416 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1417 1418 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1419 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1420 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1421 } 1422 } 1423 1424 /* 1425 * Move filecaps structure to the new place and clear the old place. 1426 */ 1427 void 1428 filecaps_move(struct filecaps *src, struct filecaps *dst) 1429 { 1430 1431 *dst = *src; 1432 bzero(src, sizeof(*src)); 1433 } 1434 1435 /* 1436 * Fill the given filecaps structure with full rights. 1437 */ 1438 static void 1439 filecaps_fill(struct filecaps *fcaps) 1440 { 1441 1442 CAP_ALL(&fcaps->fc_rights); 1443 fcaps->fc_ioctls = NULL; 1444 fcaps->fc_nioctls = -1; 1445 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1446 } 1447 1448 /* 1449 * Free memory allocated within filecaps structure. 1450 */ 1451 void 1452 filecaps_free(struct filecaps *fcaps) 1453 { 1454 1455 free(fcaps->fc_ioctls, M_FILECAPS); 1456 bzero(fcaps, sizeof(*fcaps)); 1457 } 1458 1459 /* 1460 * Validate the given filecaps structure. 1461 */ 1462 static void 1463 filecaps_validate(const struct filecaps *fcaps, const char *func) 1464 { 1465 1466 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1467 ("%s: invalid rights", func)); 1468 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1469 ("%s: invalid fcntls", func)); 1470 KASSERT(fcaps->fc_fcntls == 0 || 1471 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1472 ("%s: fcntls without CAP_FCNTL", func)); 1473 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1474 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1475 ("%s: invalid ioctls", func)); 1476 KASSERT(fcaps->fc_nioctls == 0 || 1477 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1478 ("%s: ioctls without CAP_IOCTL", func)); 1479 } 1480 1481 static void 1482 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1483 { 1484 int nfd1, maxfd; 1485 1486 FILEDESC_XLOCK_ASSERT(fdp); 1487 1488 nfd1 = fdp->fd_nfiles * 2; 1489 if (nfd1 < nfd) 1490 nfd1 = nfd; 1491 maxfd = getmaxfd(curproc); 1492 if (maxfd < nfd1) 1493 nfd1 = maxfd; 1494 KASSERT(nfd <= nfd1, 1495 ("too low nfd1 %d %d %d %d", nfd, fdp->fd_nfiles, maxfd, nfd1)); 1496 fdgrowtable(fdp, nfd1); 1497 } 1498 1499 /* 1500 * Grow the file table to accomodate (at least) nfd descriptors. 1501 */ 1502 static void 1503 fdgrowtable(struct filedesc *fdp, int nfd) 1504 { 1505 struct filedesc0 *fdp0; 1506 struct freetable *ft; 1507 struct filedescent *ntable; 1508 struct filedescent *otable; 1509 int nnfiles, onfiles; 1510 NDSLOTTYPE *nmap, *omap; 1511 1512 FILEDESC_XLOCK_ASSERT(fdp); 1513 1514 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1515 1516 /* save old values */ 1517 onfiles = fdp->fd_nfiles; 1518 otable = fdp->fd_ofiles; 1519 omap = fdp->fd_map; 1520 1521 /* compute the size of the new table */ 1522 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1523 if (nnfiles <= onfiles) 1524 /* the table is already large enough */ 1525 return; 1526 1527 /* 1528 * Allocate a new table and map. We need enough space for the 1529 * file entries themselves and the struct freetable we will use 1530 * when we decommission the table and place it on the freelist. 1531 * We place the struct freetable in the middle so we don't have 1532 * to worry about padding. 1533 */ 1534 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1535 M_FILEDESC, M_ZERO | M_WAITOK); 1536 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1537 M_ZERO | M_WAITOK); 1538 1539 /* copy the old data over and point at the new tables */ 1540 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1541 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1542 1543 /* update the pointers and counters */ 1544 memcpy(ntable, otable, onfiles * sizeof(ntable[0])); 1545 fdp->fd_ofiles = ntable; 1546 fdp->fd_map = nmap; 1547 1548 /* 1549 * In order to have a valid pattern for fget_unlocked() 1550 * fdp->fd_nfiles must be the last member to be updated, otherwise 1551 * fget_unlocked() consumers may reference a new, higher value for 1552 * fdp->fd_nfiles before to access the fdp->fd_ofiles array, 1553 * resulting in OOB accesses. 1554 */ 1555 atomic_store_rel_int(&fdp->fd_nfiles, nnfiles); 1556 1557 /* 1558 * Do not free the old file table, as some threads may still 1559 * reference entries within it. Instead, place it on a freelist 1560 * which will be processed when the struct filedesc is released. 1561 * 1562 * Do, however, free the old map. 1563 * 1564 * Note that if onfiles == NDFILE, we're dealing with the original 1565 * static allocation contained within (struct filedesc0 *)fdp, 1566 * which must not be freed. 1567 */ 1568 if (onfiles > NDFILE) { 1569 ft = (struct freetable *)&otable[onfiles]; 1570 fdp0 = (struct filedesc0 *)fdp; 1571 ft->ft_table = otable; 1572 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1573 free(omap, M_FILEDESC); 1574 } 1575 } 1576 1577 /* 1578 * Allocate a file descriptor for the process. 1579 */ 1580 int 1581 fdalloc(struct thread *td, int minfd, int *result) 1582 { 1583 struct proc *p = td->td_proc; 1584 struct filedesc *fdp = p->p_fd; 1585 int fd = -1, maxfd, allocfd; 1586 #ifdef RACCT 1587 int error; 1588 #endif 1589 1590 FILEDESC_XLOCK_ASSERT(fdp); 1591 1592 if (fdp->fd_freefile > minfd) 1593 minfd = fdp->fd_freefile; 1594 1595 maxfd = getmaxfd(p); 1596 1597 /* 1598 * Search the bitmap for a free descriptor starting at minfd. 1599 * If none is found, grow the file table. 1600 */ 1601 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1602 if (fd >= maxfd) 1603 return (EMFILE); 1604 if (fd >= fdp->fd_nfiles) { 1605 allocfd = min(fd * 2, maxfd); 1606 #ifdef RACCT 1607 PROC_LOCK(p); 1608 error = racct_set(p, RACCT_NOFILE, allocfd); 1609 PROC_UNLOCK(p); 1610 if (error != 0) 1611 return (EMFILE); 1612 #endif 1613 /* 1614 * fd is already equal to first free descriptor >= minfd, so 1615 * we only need to grow the table and we are done. 1616 */ 1617 fdgrowtable_exp(fdp, allocfd); 1618 } 1619 1620 /* 1621 * Perform some sanity checks, then mark the file descriptor as 1622 * used and return it to the caller. 1623 */ 1624 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1625 ("invalid descriptor %d", fd)); 1626 KASSERT(!fdisused(fdp, fd), 1627 ("fd_first_free() returned non-free descriptor")); 1628 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1629 ("file descriptor isn't free")); 1630 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1631 fdused(fdp, fd); 1632 *result = fd; 1633 return (0); 1634 } 1635 1636 /* 1637 * Allocate n file descriptors for the process. 1638 */ 1639 int 1640 fdallocn(struct thread *td, int minfd, int *fds, int n) 1641 { 1642 struct proc *p = td->td_proc; 1643 struct filedesc *fdp = p->p_fd; 1644 int i; 1645 1646 FILEDESC_XLOCK_ASSERT(fdp); 1647 1648 if (!fdavail(td, n)) 1649 return (EMFILE); 1650 1651 for (i = 0; i < n; i++) 1652 if (fdalloc(td, 0, &fds[i]) != 0) 1653 break; 1654 1655 if (i < n) { 1656 for (i--; i >= 0; i--) 1657 fdunused(fdp, fds[i]); 1658 return (EMFILE); 1659 } 1660 1661 return (0); 1662 } 1663 1664 /* 1665 * Check to see whether n user file descriptors are available to the process 1666 * p. 1667 */ 1668 int 1669 fdavail(struct thread *td, int n) 1670 { 1671 struct proc *p = td->td_proc; 1672 struct filedesc *fdp = td->td_proc->p_fd; 1673 int i, lim, last; 1674 1675 FILEDESC_LOCK_ASSERT(fdp); 1676 1677 /* 1678 * XXX: This is only called from uipc_usrreq.c:unp_externalize(); 1679 * call racct_add() from there instead of dealing with containers 1680 * here. 1681 */ 1682 lim = getmaxfd(p); 1683 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) 1684 return (1); 1685 last = min(fdp->fd_nfiles, lim); 1686 for (i = fdp->fd_freefile; i < last; i++) { 1687 if (fdp->fd_ofiles[i].fde_file == NULL && --n <= 0) 1688 return (1); 1689 } 1690 return (0); 1691 } 1692 1693 /* 1694 * Create a new open file structure and allocate a file decriptor for the 1695 * process that refers to it. We add one reference to the file for the 1696 * descriptor table and one reference for resultfp. This is to prevent us 1697 * being preempted and the entry in the descriptor table closed after we 1698 * release the FILEDESC lock. 1699 */ 1700 int 1701 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1702 { 1703 struct file *fp; 1704 int error, fd; 1705 1706 error = falloc_noinstall(td, &fp); 1707 if (error) 1708 return (error); /* no reference held on error */ 1709 1710 error = finstall(td, fp, &fd, flags, NULL); 1711 if (error) { 1712 fdrop(fp, td); /* one reference (fp only) */ 1713 return (error); 1714 } 1715 1716 if (resultfp != NULL) 1717 *resultfp = fp; /* copy out result */ 1718 else 1719 fdrop(fp, td); /* release local reference */ 1720 1721 if (resultfd != NULL) 1722 *resultfd = fd; 1723 1724 return (0); 1725 } 1726 1727 /* 1728 * Create a new open file structure without allocating a file descriptor. 1729 */ 1730 int 1731 falloc_noinstall(struct thread *td, struct file **resultfp) 1732 { 1733 struct file *fp; 1734 int maxuserfiles = maxfiles - (maxfiles / 20); 1735 static struct timeval lastfail; 1736 static int curfail; 1737 1738 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1739 1740 if ((openfiles >= maxuserfiles && 1741 priv_check(td, PRIV_MAXFILES) != 0) || 1742 openfiles >= maxfiles) { 1743 if (ppsratecheck(&lastfail, &curfail, 1)) { 1744 printf("kern.maxfiles limit exceeded by uid %i, " 1745 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1746 } 1747 return (ENFILE); 1748 } 1749 atomic_add_int(&openfiles, 1); 1750 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1751 refcount_init(&fp->f_count, 1); 1752 fp->f_cred = crhold(td->td_ucred); 1753 fp->f_ops = &badfileops; 1754 fp->f_data = NULL; 1755 fp->f_vnode = NULL; 1756 *resultfp = fp; 1757 return (0); 1758 } 1759 1760 /* 1761 * Install a file in a file descriptor table. 1762 */ 1763 int 1764 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1765 struct filecaps *fcaps) 1766 { 1767 struct filedesc *fdp = td->td_proc->p_fd; 1768 struct filedescent *fde; 1769 int error; 1770 1771 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1772 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1773 if (fcaps != NULL) 1774 filecaps_validate(fcaps, __func__); 1775 1776 FILEDESC_XLOCK(fdp); 1777 if ((error = fdalloc(td, 0, fd))) { 1778 FILEDESC_XUNLOCK(fdp); 1779 return (error); 1780 } 1781 fhold(fp); 1782 fde = &fdp->fd_ofiles[*fd]; 1783 fde->fde_file = fp; 1784 if ((flags & O_CLOEXEC) != 0) 1785 fde->fde_flags |= UF_EXCLOSE; 1786 if (fcaps != NULL) 1787 filecaps_move(fcaps, &fde->fde_caps); 1788 else 1789 filecaps_fill(&fde->fde_caps); 1790 FILEDESC_XUNLOCK(fdp); 1791 return (0); 1792 } 1793 1794 /* 1795 * Build a new filedesc structure from another. 1796 * Copy the current, root, and jail root vnode references. 1797 */ 1798 struct filedesc * 1799 fdinit(struct filedesc *fdp) 1800 { 1801 struct filedesc0 *newfdp; 1802 1803 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1804 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1805 if (fdp != NULL) { 1806 FILEDESC_XLOCK(fdp); 1807 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1808 if (newfdp->fd_fd.fd_cdir) 1809 VREF(newfdp->fd_fd.fd_cdir); 1810 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1811 if (newfdp->fd_fd.fd_rdir) 1812 VREF(newfdp->fd_fd.fd_rdir); 1813 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1814 if (newfdp->fd_fd.fd_jdir) 1815 VREF(newfdp->fd_fd.fd_jdir); 1816 FILEDESC_XUNLOCK(fdp); 1817 } 1818 1819 /* Create the file descriptor table. */ 1820 newfdp->fd_fd.fd_refcnt = 1; 1821 newfdp->fd_fd.fd_holdcnt = 1; 1822 newfdp->fd_fd.fd_cmask = CMASK; 1823 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1824 newfdp->fd_fd.fd_nfiles = NDFILE; 1825 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1826 newfdp->fd_fd.fd_lastfile = -1; 1827 return (&newfdp->fd_fd); 1828 } 1829 1830 static struct filedesc * 1831 fdhold(struct proc *p) 1832 { 1833 struct filedesc *fdp; 1834 1835 mtx_lock(&fdesc_mtx); 1836 fdp = p->p_fd; 1837 if (fdp != NULL) 1838 fdp->fd_holdcnt++; 1839 mtx_unlock(&fdesc_mtx); 1840 return (fdp); 1841 } 1842 1843 static void 1844 fddrop(struct filedesc *fdp) 1845 { 1846 struct filedesc0 *fdp0; 1847 struct freetable *ft; 1848 int i; 1849 1850 mtx_lock(&fdesc_mtx); 1851 i = --fdp->fd_holdcnt; 1852 mtx_unlock(&fdesc_mtx); 1853 if (i > 0) 1854 return; 1855 1856 FILEDESC_LOCK_DESTROY(fdp); 1857 fdp0 = (struct filedesc0 *)fdp; 1858 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1859 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1860 free(ft->ft_table, M_FILEDESC); 1861 } 1862 free(fdp, M_FILEDESC); 1863 } 1864 1865 /* 1866 * Share a filedesc structure. 1867 */ 1868 struct filedesc * 1869 fdshare(struct filedesc *fdp) 1870 { 1871 1872 FILEDESC_XLOCK(fdp); 1873 fdp->fd_refcnt++; 1874 FILEDESC_XUNLOCK(fdp); 1875 return (fdp); 1876 } 1877 1878 /* 1879 * Unshare a filedesc structure, if necessary by making a copy 1880 */ 1881 void 1882 fdunshare(struct proc *p, struct thread *td) 1883 { 1884 1885 FILEDESC_XLOCK(p->p_fd); 1886 if (p->p_fd->fd_refcnt > 1) { 1887 struct filedesc *tmp; 1888 1889 FILEDESC_XUNLOCK(p->p_fd); 1890 tmp = fdcopy(p->p_fd); 1891 fdescfree(td); 1892 p->p_fd = tmp; 1893 } else 1894 FILEDESC_XUNLOCK(p->p_fd); 1895 } 1896 1897 /* 1898 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1899 * this is to ease callers, not catch errors. 1900 */ 1901 struct filedesc * 1902 fdcopy(struct filedesc *fdp) 1903 { 1904 struct filedesc *newfdp; 1905 struct filedescent *nfde, *ofde; 1906 int i; 1907 1908 /* Certain daemons might not have file descriptors. */ 1909 if (fdp == NULL) 1910 return (NULL); 1911 1912 newfdp = fdinit(fdp); 1913 FILEDESC_SLOCK(fdp); 1914 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1915 FILEDESC_SUNLOCK(fdp); 1916 FILEDESC_XLOCK(newfdp); 1917 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1918 FILEDESC_XUNLOCK(newfdp); 1919 FILEDESC_SLOCK(fdp); 1920 } 1921 /* copy all passable descriptors (i.e. not kqueue) */ 1922 newfdp->fd_freefile = -1; 1923 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1924 ofde = &fdp->fd_ofiles[i]; 1925 if (fdisused(fdp, i) && 1926 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1927 ofde->fde_file->f_ops != &badfileops) { 1928 nfde = &newfdp->fd_ofiles[i]; 1929 *nfde = *ofde; 1930 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1931 fhold(nfde->fde_file); 1932 newfdp->fd_lastfile = i; 1933 } else { 1934 if (newfdp->fd_freefile == -1) 1935 newfdp->fd_freefile = i; 1936 } 1937 } 1938 newfdp->fd_cmask = fdp->fd_cmask; 1939 FILEDESC_SUNLOCK(fdp); 1940 FILEDESC_XLOCK(newfdp); 1941 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1942 if (newfdp->fd_ofiles[i].fde_file != NULL) 1943 fdused(newfdp, i); 1944 } 1945 if (newfdp->fd_freefile == -1) 1946 newfdp->fd_freefile = i; 1947 FILEDESC_XUNLOCK(newfdp); 1948 return (newfdp); 1949 } 1950 1951 /* 1952 * Release a filedesc structure. 1953 */ 1954 void 1955 fdescfree(struct thread *td) 1956 { 1957 struct filedesc *fdp; 1958 int i; 1959 struct filedesc_to_leader *fdtol; 1960 struct file *fp; 1961 struct vnode *cdir, *jdir, *rdir, *vp; 1962 struct flock lf; 1963 1964 /* Certain daemons might not have file descriptors. */ 1965 fdp = td->td_proc->p_fd; 1966 if (fdp == NULL) 1967 return; 1968 1969 #ifdef RACCT 1970 PROC_LOCK(td->td_proc); 1971 racct_set(td->td_proc, RACCT_NOFILE, 0); 1972 PROC_UNLOCK(td->td_proc); 1973 #endif 1974 1975 /* Check for special need to clear POSIX style locks */ 1976 fdtol = td->td_proc->p_fdtol; 1977 if (fdtol != NULL) { 1978 FILEDESC_XLOCK(fdp); 1979 KASSERT(fdtol->fdl_refcount > 0, 1980 ("filedesc_to_refcount botch: fdl_refcount=%d", 1981 fdtol->fdl_refcount)); 1982 if (fdtol->fdl_refcount == 1 && 1983 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1984 for (i = 0; i <= fdp->fd_lastfile; i++) { 1985 fp = fdp->fd_ofiles[i].fde_file; 1986 if (fp == NULL || fp->f_type != DTYPE_VNODE) 1987 continue; 1988 fhold(fp); 1989 FILEDESC_XUNLOCK(fdp); 1990 lf.l_whence = SEEK_SET; 1991 lf.l_start = 0; 1992 lf.l_len = 0; 1993 lf.l_type = F_UNLCK; 1994 vp = fp->f_vnode; 1995 (void) VOP_ADVLOCK(vp, 1996 (caddr_t)td->td_proc->p_leader, F_UNLCK, 1997 &lf, F_POSIX); 1998 FILEDESC_XLOCK(fdp); 1999 fdrop(fp, td); 2000 } 2001 } 2002 retry: 2003 if (fdtol->fdl_refcount == 1) { 2004 if (fdp->fd_holdleaderscount > 0 && 2005 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2006 /* 2007 * close() or do_dup() has cleared a reference 2008 * in a shared file descriptor table. 2009 */ 2010 fdp->fd_holdleaderswakeup = 1; 2011 sx_sleep(&fdp->fd_holdleaderscount, 2012 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2013 goto retry; 2014 } 2015 if (fdtol->fdl_holdcount > 0) { 2016 /* 2017 * Ensure that fdtol->fdl_leader remains 2018 * valid in closef(). 2019 */ 2020 fdtol->fdl_wakeup = 1; 2021 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2022 "fdlhold", 0); 2023 goto retry; 2024 } 2025 } 2026 fdtol->fdl_refcount--; 2027 if (fdtol->fdl_refcount == 0 && 2028 fdtol->fdl_holdcount == 0) { 2029 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2030 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2031 } else 2032 fdtol = NULL; 2033 td->td_proc->p_fdtol = NULL; 2034 FILEDESC_XUNLOCK(fdp); 2035 if (fdtol != NULL) 2036 free(fdtol, M_FILEDESC_TO_LEADER); 2037 } 2038 FILEDESC_XLOCK(fdp); 2039 i = --fdp->fd_refcnt; 2040 FILEDESC_XUNLOCK(fdp); 2041 if (i > 0) 2042 return; 2043 2044 for (i = 0; i <= fdp->fd_lastfile; i++) { 2045 fp = fdp->fd_ofiles[i].fde_file; 2046 if (fp != NULL) { 2047 FILEDESC_XLOCK(fdp); 2048 fdfree(fdp, i); 2049 FILEDESC_XUNLOCK(fdp); 2050 (void) closef(fp, td); 2051 } 2052 } 2053 FILEDESC_XLOCK(fdp); 2054 2055 /* XXX This should happen earlier. */ 2056 mtx_lock(&fdesc_mtx); 2057 td->td_proc->p_fd = NULL; 2058 mtx_unlock(&fdesc_mtx); 2059 2060 if (fdp->fd_nfiles > NDFILE) 2061 free(fdp->fd_ofiles, M_FILEDESC); 2062 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2063 free(fdp->fd_map, M_FILEDESC); 2064 2065 fdp->fd_nfiles = 0; 2066 2067 cdir = fdp->fd_cdir; 2068 fdp->fd_cdir = NULL; 2069 rdir = fdp->fd_rdir; 2070 fdp->fd_rdir = NULL; 2071 jdir = fdp->fd_jdir; 2072 fdp->fd_jdir = NULL; 2073 FILEDESC_XUNLOCK(fdp); 2074 2075 if (cdir != NULL) 2076 vrele(cdir); 2077 if (rdir != NULL) 2078 vrele(rdir); 2079 if (jdir != NULL) 2080 vrele(jdir); 2081 2082 fddrop(fdp); 2083 } 2084 2085 /* 2086 * For setugid programs, we don't want to people to use that setugidness 2087 * to generate error messages which write to a file which otherwise would 2088 * otherwise be off-limits to the process. We check for filesystems where 2089 * the vnode can change out from under us after execve (like [lin]procfs). 2090 * 2091 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2092 * sufficient. We also don't check for setugidness since we know we are. 2093 */ 2094 static int 2095 is_unsafe(struct file *fp) 2096 { 2097 if (fp->f_type == DTYPE_VNODE) { 2098 struct vnode *vp = fp->f_vnode; 2099 2100 if ((vp->v_vflag & VV_PROCDEP) != 0) 2101 return (1); 2102 } 2103 return (0); 2104 } 2105 2106 /* 2107 * Make this setguid thing safe, if at all possible. 2108 */ 2109 void 2110 setugidsafety(struct thread *td) 2111 { 2112 struct filedesc *fdp; 2113 struct file *fp; 2114 int i; 2115 2116 /* Certain daemons might not have file descriptors. */ 2117 fdp = td->td_proc->p_fd; 2118 if (fdp == NULL) 2119 return; 2120 2121 /* 2122 * Note: fdp->fd_ofiles may be reallocated out from under us while 2123 * we are blocked in a close. Be careful! 2124 */ 2125 FILEDESC_XLOCK(fdp); 2126 for (i = 0; i <= fdp->fd_lastfile; i++) { 2127 if (i > 2) 2128 break; 2129 fp = fdp->fd_ofiles[i].fde_file; 2130 if (fp != NULL && is_unsafe(fp)) { 2131 knote_fdclose(td, i); 2132 /* 2133 * NULL-out descriptor prior to close to avoid 2134 * a race while close blocks. 2135 */ 2136 fdfree(fdp, i); 2137 FILEDESC_XUNLOCK(fdp); 2138 (void) closef(fp, td); 2139 FILEDESC_XLOCK(fdp); 2140 } 2141 } 2142 FILEDESC_XUNLOCK(fdp); 2143 } 2144 2145 /* 2146 * If a specific file object occupies a specific file descriptor, close the 2147 * file descriptor entry and drop a reference on the file object. This is a 2148 * convenience function to handle a subsequent error in a function that calls 2149 * falloc() that handles the race that another thread might have closed the 2150 * file descriptor out from under the thread creating the file object. 2151 */ 2152 void 2153 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2154 { 2155 2156 FILEDESC_XLOCK(fdp); 2157 if (fdp->fd_ofiles[idx].fde_file == fp) { 2158 fdfree(fdp, idx); 2159 FILEDESC_XUNLOCK(fdp); 2160 fdrop(fp, td); 2161 } else 2162 FILEDESC_XUNLOCK(fdp); 2163 } 2164 2165 /* 2166 * Close any files on exec? 2167 */ 2168 void 2169 fdcloseexec(struct thread *td) 2170 { 2171 struct filedesc *fdp; 2172 struct filedescent *fde; 2173 struct file *fp; 2174 int i; 2175 2176 /* Certain daemons might not have file descriptors. */ 2177 fdp = td->td_proc->p_fd; 2178 if (fdp == NULL) 2179 return; 2180 2181 /* 2182 * We cannot cache fd_ofiles since operations 2183 * may block and rip them out from under us. 2184 */ 2185 FILEDESC_XLOCK(fdp); 2186 for (i = 0; i <= fdp->fd_lastfile; i++) { 2187 fde = &fdp->fd_ofiles[i]; 2188 fp = fde->fde_file; 2189 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2190 (fde->fde_flags & UF_EXCLOSE))) { 2191 fdfree(fdp, i); 2192 (void) closefp(fdp, i, fp, td, 0); 2193 /* closefp() drops the FILEDESC lock. */ 2194 FILEDESC_XLOCK(fdp); 2195 } 2196 } 2197 FILEDESC_XUNLOCK(fdp); 2198 } 2199 2200 /* 2201 * It is unsafe for set[ug]id processes to be started with file 2202 * descriptors 0..2 closed, as these descriptors are given implicit 2203 * significance in the Standard C library. fdcheckstd() will create a 2204 * descriptor referencing /dev/null for each of stdin, stdout, and 2205 * stderr that is not already open. 2206 */ 2207 int 2208 fdcheckstd(struct thread *td) 2209 { 2210 struct filedesc *fdp; 2211 register_t retval, save; 2212 int i, error, devnull; 2213 2214 fdp = td->td_proc->p_fd; 2215 if (fdp == NULL) 2216 return (0); 2217 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2218 devnull = -1; 2219 error = 0; 2220 for (i = 0; i < 3; i++) { 2221 if (fdp->fd_ofiles[i].fde_file != NULL) 2222 continue; 2223 if (devnull < 0) { 2224 save = td->td_retval[0]; 2225 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2226 O_RDWR, 0); 2227 devnull = td->td_retval[0]; 2228 td->td_retval[0] = save; 2229 if (error) 2230 break; 2231 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2232 } else { 2233 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2234 if (error != 0) 2235 break; 2236 } 2237 } 2238 return (error); 2239 } 2240 2241 /* 2242 * Internal form of close. Decrement reference count on file structure. 2243 * Note: td may be NULL when closing a file that was being passed in a 2244 * message. 2245 * 2246 * XXXRW: Giant is not required for the caller, but often will be held; this 2247 * makes it moderately likely the Giant will be recursed in the VFS case. 2248 */ 2249 int 2250 closef(struct file *fp, struct thread *td) 2251 { 2252 struct vnode *vp; 2253 struct flock lf; 2254 struct filedesc_to_leader *fdtol; 2255 struct filedesc *fdp; 2256 2257 /* 2258 * POSIX record locking dictates that any close releases ALL 2259 * locks owned by this process. This is handled by setting 2260 * a flag in the unlock to free ONLY locks obeying POSIX 2261 * semantics, and not to free BSD-style file locks. 2262 * If the descriptor was in a message, POSIX-style locks 2263 * aren't passed with the descriptor, and the thread pointer 2264 * will be NULL. Callers should be careful only to pass a 2265 * NULL thread pointer when there really is no owning 2266 * context that might have locks, or the locks will be 2267 * leaked. 2268 */ 2269 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2270 vp = fp->f_vnode; 2271 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2272 lf.l_whence = SEEK_SET; 2273 lf.l_start = 0; 2274 lf.l_len = 0; 2275 lf.l_type = F_UNLCK; 2276 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2277 F_UNLCK, &lf, F_POSIX); 2278 } 2279 fdtol = td->td_proc->p_fdtol; 2280 if (fdtol != NULL) { 2281 /* 2282 * Handle special case where file descriptor table is 2283 * shared between multiple process leaders. 2284 */ 2285 fdp = td->td_proc->p_fd; 2286 FILEDESC_XLOCK(fdp); 2287 for (fdtol = fdtol->fdl_next; 2288 fdtol != td->td_proc->p_fdtol; 2289 fdtol = fdtol->fdl_next) { 2290 if ((fdtol->fdl_leader->p_flag & 2291 P_ADVLOCK) == 0) 2292 continue; 2293 fdtol->fdl_holdcount++; 2294 FILEDESC_XUNLOCK(fdp); 2295 lf.l_whence = SEEK_SET; 2296 lf.l_start = 0; 2297 lf.l_len = 0; 2298 lf.l_type = F_UNLCK; 2299 vp = fp->f_vnode; 2300 (void) VOP_ADVLOCK(vp, 2301 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2302 F_POSIX); 2303 FILEDESC_XLOCK(fdp); 2304 fdtol->fdl_holdcount--; 2305 if (fdtol->fdl_holdcount == 0 && 2306 fdtol->fdl_wakeup != 0) { 2307 fdtol->fdl_wakeup = 0; 2308 wakeup(fdtol); 2309 } 2310 } 2311 FILEDESC_XUNLOCK(fdp); 2312 } 2313 } 2314 return (fdrop(fp, td)); 2315 } 2316 2317 /* 2318 * Initialize the file pointer with the specified properties. 2319 * 2320 * The ops are set with release semantics to be certain that the flags, type, 2321 * and data are visible when ops is. This is to prevent ops methods from being 2322 * called with bad data. 2323 */ 2324 void 2325 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2326 { 2327 fp->f_data = data; 2328 fp->f_flag = flag; 2329 fp->f_type = type; 2330 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2331 } 2332 2333 int 2334 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2335 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2336 { 2337 struct file *fp; 2338 u_int count; 2339 #ifdef CAPABILITIES 2340 cap_rights_t haverights; 2341 int error; 2342 #endif 2343 2344 /* 2345 * Avoid reads reordering and then a first access to the 2346 * fdp->fd_ofiles table which could result in OOB operation. 2347 */ 2348 if (fd < 0 || fd >= atomic_load_acq_int(&fdp->fd_nfiles)) 2349 return (EBADF); 2350 /* 2351 * Fetch the descriptor locklessly. We avoid fdrop() races by 2352 * never raising a refcount above 0. To accomplish this we have 2353 * to use a cmpset loop rather than an atomic_add. The descriptor 2354 * must be re-verified once we acquire a reference to be certain 2355 * that the identity is still correct and we did not lose a race 2356 * due to preemption. 2357 */ 2358 for (;;) { 2359 fp = fdp->fd_ofiles[fd].fde_file; 2360 if (fp == NULL) 2361 return (EBADF); 2362 #ifdef CAPABILITIES 2363 haverights = *cap_rights(fdp, fd); 2364 if (needrightsp != NULL) { 2365 error = cap_check(&haverights, needrightsp); 2366 if (error != 0) 2367 return (error); 2368 if (cap_rights_is_set(needrightsp, CAP_FCNTL)) { 2369 error = cap_fcntl_check(fdp, fd, needfcntl); 2370 if (error != 0) 2371 return (error); 2372 } 2373 } 2374 #endif 2375 count = fp->f_count; 2376 if (count == 0) 2377 continue; 2378 /* 2379 * Use an acquire barrier to prevent caching of fd_ofiles 2380 * so it is refreshed for verification. 2381 */ 2382 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2383 continue; 2384 if (fp == fdp->fd_ofiles[fd].fde_file) 2385 break; 2386 fdrop(fp, curthread); 2387 } 2388 *fpp = fp; 2389 if (haverightsp != NULL) { 2390 #ifdef CAPABILITIES 2391 *haverightsp = haverights; 2392 #else 2393 CAP_ALL(haverightsp); 2394 #endif 2395 } 2396 return (0); 2397 } 2398 2399 /* 2400 * Extract the file pointer associated with the specified descriptor for the 2401 * current user process. 2402 * 2403 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2404 * returned. 2405 * 2406 * File's rights will be checked against the capability rights mask. 2407 * 2408 * If an error occured the non-zero error is returned and *fpp is set to 2409 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2410 * responsible for fdrop(). 2411 */ 2412 static __inline int 2413 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2414 cap_rights_t *needrightsp, u_char *maxprotp) 2415 { 2416 struct filedesc *fdp; 2417 struct file *fp; 2418 cap_rights_t haverights, needrights; 2419 int error; 2420 2421 *fpp = NULL; 2422 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2423 return (EBADF); 2424 if (needrightsp != NULL) 2425 needrights = *needrightsp; 2426 else 2427 cap_rights_init(&needrights); 2428 if (maxprotp != NULL) 2429 cap_rights_set(&needrights, CAP_MMAP); 2430 error = fget_unlocked(fdp, fd, &needrights, 0, &fp, &haverights); 2431 if (error != 0) 2432 return (error); 2433 if (fp->f_ops == &badfileops) { 2434 fdrop(fp, td); 2435 return (EBADF); 2436 } 2437 2438 #ifdef CAPABILITIES 2439 /* 2440 * If requested, convert capability rights to access flags. 2441 */ 2442 if (maxprotp != NULL) 2443 *maxprotp = cap_rights_to_vmprot(&haverights); 2444 #else /* !CAPABILITIES */ 2445 if (maxprotp != NULL) 2446 *maxprotp = VM_PROT_ALL; 2447 #endif /* CAPABILITIES */ 2448 2449 /* 2450 * FREAD and FWRITE failure return EBADF as per POSIX. 2451 */ 2452 error = 0; 2453 switch (flags) { 2454 case FREAD: 2455 case FWRITE: 2456 if ((fp->f_flag & flags) == 0) 2457 error = EBADF; 2458 break; 2459 case FEXEC: 2460 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2461 ((fp->f_flag & FWRITE) != 0)) 2462 error = EBADF; 2463 break; 2464 case 0: 2465 break; 2466 default: 2467 KASSERT(0, ("wrong flags")); 2468 } 2469 2470 if (error != 0) { 2471 fdrop(fp, td); 2472 return (error); 2473 } 2474 2475 *fpp = fp; 2476 return (0); 2477 } 2478 2479 int 2480 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2481 { 2482 2483 return(_fget(td, fd, fpp, 0, rightsp, NULL)); 2484 } 2485 2486 int 2487 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2488 struct file **fpp) 2489 { 2490 2491 return (_fget(td, fd, fpp, 0, rightsp, maxprotp)); 2492 } 2493 2494 int 2495 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2496 { 2497 2498 return(_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2499 } 2500 2501 int 2502 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2503 { 2504 2505 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2506 } 2507 2508 /* 2509 * Like fget() but loads the underlying vnode, or returns an error if the 2510 * descriptor does not represent a vnode. Note that pipes use vnodes but 2511 * never have VM objects. The returned vnode will be vref()'d. 2512 * 2513 * XXX: what about the unused flags ? 2514 */ 2515 static __inline int 2516 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2517 struct vnode **vpp) 2518 { 2519 struct file *fp; 2520 int error; 2521 2522 *vpp = NULL; 2523 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2524 if (error != 0) 2525 return (error); 2526 if (fp->f_vnode == NULL) { 2527 error = EINVAL; 2528 } else { 2529 *vpp = fp->f_vnode; 2530 vref(*vpp); 2531 } 2532 fdrop(fp, td); 2533 2534 return (error); 2535 } 2536 2537 int 2538 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2539 { 2540 2541 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2542 } 2543 2544 int 2545 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2546 struct filecaps *havecaps, struct vnode **vpp) 2547 { 2548 struct filedesc *fdp; 2549 struct file *fp; 2550 #ifdef CAPABILITIES 2551 int error; 2552 #endif 2553 2554 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2555 return (EBADF); 2556 2557 fp = fget_locked(fdp, fd); 2558 if (fp == NULL || fp->f_ops == &badfileops) 2559 return (EBADF); 2560 2561 #ifdef CAPABILITIES 2562 if (needrightsp != NULL) { 2563 error = cap_check(cap_rights(fdp, fd), needrightsp); 2564 if (error != 0) 2565 return (error); 2566 } 2567 #endif 2568 2569 if (fp->f_vnode == NULL) 2570 return (EINVAL); 2571 2572 *vpp = fp->f_vnode; 2573 vref(*vpp); 2574 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2575 2576 return (0); 2577 } 2578 2579 int 2580 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2581 { 2582 2583 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2584 } 2585 2586 int 2587 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2588 { 2589 2590 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2591 } 2592 2593 #ifdef notyet 2594 int 2595 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2596 struct vnode **vpp) 2597 { 2598 2599 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2600 } 2601 #endif 2602 2603 /* 2604 * Like fget() but loads the underlying socket, or returns an error if the 2605 * descriptor does not represent a socket. 2606 * 2607 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2608 * in the future. 2609 * 2610 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2611 * on their file descriptor reference to prevent the socket from being free'd 2612 * during use. 2613 */ 2614 int 2615 fgetsock(struct thread *td, int fd, cap_rights_t *rightsp, struct socket **spp, 2616 u_int *fflagp) 2617 { 2618 struct file *fp; 2619 int error; 2620 2621 *spp = NULL; 2622 if (fflagp != NULL) 2623 *fflagp = 0; 2624 if ((error = _fget(td, fd, &fp, 0, rightsp, NULL)) != 0) 2625 return (error); 2626 if (fp->f_type != DTYPE_SOCKET) { 2627 error = ENOTSOCK; 2628 } else { 2629 *spp = fp->f_data; 2630 if (fflagp) 2631 *fflagp = fp->f_flag; 2632 SOCK_LOCK(*spp); 2633 soref(*spp); 2634 SOCK_UNLOCK(*spp); 2635 } 2636 fdrop(fp, td); 2637 2638 return (error); 2639 } 2640 2641 /* 2642 * Drop the reference count on the socket and XXX release the SX lock in the 2643 * future. The last reference closes the socket. 2644 * 2645 * Note: fputsock() is deprecated, see comment for fgetsock(). 2646 */ 2647 void 2648 fputsock(struct socket *so) 2649 { 2650 2651 ACCEPT_LOCK(); 2652 SOCK_LOCK(so); 2653 CURVNET_SET(so->so_vnet); 2654 sorele(so); 2655 CURVNET_RESTORE(); 2656 } 2657 2658 /* 2659 * Handle the last reference to a file being closed. 2660 */ 2661 int 2662 _fdrop(struct file *fp, struct thread *td) 2663 { 2664 int error; 2665 2666 error = 0; 2667 if (fp->f_count != 0) 2668 panic("fdrop: count %d", fp->f_count); 2669 if (fp->f_ops != &badfileops) 2670 error = fo_close(fp, td); 2671 atomic_subtract_int(&openfiles, 1); 2672 crfree(fp->f_cred); 2673 free(fp->f_advice, M_FADVISE); 2674 uma_zfree(file_zone, fp); 2675 2676 return (error); 2677 } 2678 2679 /* 2680 * Apply an advisory lock on a file descriptor. 2681 * 2682 * Just attempt to get a record lock of the requested type on the entire file 2683 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2684 */ 2685 #ifndef _SYS_SYSPROTO_H_ 2686 struct flock_args { 2687 int fd; 2688 int how; 2689 }; 2690 #endif 2691 /* ARGSUSED */ 2692 int 2693 sys_flock(struct thread *td, struct flock_args *uap) 2694 { 2695 struct file *fp; 2696 struct vnode *vp; 2697 struct flock lf; 2698 cap_rights_t rights; 2699 int error; 2700 2701 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2702 if (error != 0) 2703 return (error); 2704 if (fp->f_type != DTYPE_VNODE) { 2705 fdrop(fp, td); 2706 return (EOPNOTSUPP); 2707 } 2708 2709 vp = fp->f_vnode; 2710 lf.l_whence = SEEK_SET; 2711 lf.l_start = 0; 2712 lf.l_len = 0; 2713 if (uap->how & LOCK_UN) { 2714 lf.l_type = F_UNLCK; 2715 atomic_clear_int(&fp->f_flag, FHASLOCK); 2716 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2717 goto done2; 2718 } 2719 if (uap->how & LOCK_EX) 2720 lf.l_type = F_WRLCK; 2721 else if (uap->how & LOCK_SH) 2722 lf.l_type = F_RDLCK; 2723 else { 2724 error = EBADF; 2725 goto done2; 2726 } 2727 atomic_set_int(&fp->f_flag, FHASLOCK); 2728 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2729 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2730 done2: 2731 fdrop(fp, td); 2732 return (error); 2733 } 2734 /* 2735 * Duplicate the specified descriptor to a free descriptor. 2736 */ 2737 int 2738 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2739 int openerror, int *indxp) 2740 { 2741 struct file *fp; 2742 int error, indx; 2743 2744 KASSERT(openerror == ENODEV || openerror == ENXIO, 2745 ("unexpected error %d in %s", openerror, __func__)); 2746 2747 /* 2748 * If the to-be-dup'd fd number is greater than the allowed number 2749 * of file descriptors, or the fd to be dup'd has already been 2750 * closed, then reject. 2751 */ 2752 FILEDESC_XLOCK(fdp); 2753 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2754 FILEDESC_XUNLOCK(fdp); 2755 return (EBADF); 2756 } 2757 2758 error = fdalloc(td, 0, &indx); 2759 if (error != 0) { 2760 FILEDESC_XUNLOCK(fdp); 2761 return (error); 2762 } 2763 2764 /* 2765 * There are two cases of interest here. 2766 * 2767 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2768 * 2769 * For ENXIO steal away the file structure from (dfd) and store it in 2770 * (indx). (dfd) is effectively closed by this operation. 2771 */ 2772 switch (openerror) { 2773 case ENODEV: 2774 /* 2775 * Check that the mode the file is being opened for is a 2776 * subset of the mode of the existing descriptor. 2777 */ 2778 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2779 fdunused(fdp, indx); 2780 FILEDESC_XUNLOCK(fdp); 2781 return (EACCES); 2782 } 2783 fhold(fp); 2784 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2785 filecaps_copy(&fdp->fd_ofiles[dfd].fde_caps, 2786 &fdp->fd_ofiles[indx].fde_caps); 2787 break; 2788 case ENXIO: 2789 /* 2790 * Steal away the file pointer from dfd and stuff it into indx. 2791 */ 2792 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2793 bzero(&fdp->fd_ofiles[dfd], sizeof(fdp->fd_ofiles[dfd])); 2794 fdunused(fdp, dfd); 2795 break; 2796 } 2797 FILEDESC_XUNLOCK(fdp); 2798 *indxp = indx; 2799 return (0); 2800 } 2801 2802 /* 2803 * Scan all active processes and prisons to see if any of them have a current 2804 * or root directory of `olddp'. If so, replace them with the new mount point. 2805 */ 2806 void 2807 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2808 { 2809 struct filedesc *fdp; 2810 struct prison *pr; 2811 struct proc *p; 2812 int nrele; 2813 2814 if (vrefcnt(olddp) == 1) 2815 return; 2816 nrele = 0; 2817 sx_slock(&allproc_lock); 2818 FOREACH_PROC_IN_SYSTEM(p) { 2819 fdp = fdhold(p); 2820 if (fdp == NULL) 2821 continue; 2822 FILEDESC_XLOCK(fdp); 2823 if (fdp->fd_cdir == olddp) { 2824 vref(newdp); 2825 fdp->fd_cdir = newdp; 2826 nrele++; 2827 } 2828 if (fdp->fd_rdir == olddp) { 2829 vref(newdp); 2830 fdp->fd_rdir = newdp; 2831 nrele++; 2832 } 2833 if (fdp->fd_jdir == olddp) { 2834 vref(newdp); 2835 fdp->fd_jdir = newdp; 2836 nrele++; 2837 } 2838 FILEDESC_XUNLOCK(fdp); 2839 fddrop(fdp); 2840 } 2841 sx_sunlock(&allproc_lock); 2842 if (rootvnode == olddp) { 2843 vref(newdp); 2844 rootvnode = newdp; 2845 nrele++; 2846 } 2847 mtx_lock(&prison0.pr_mtx); 2848 if (prison0.pr_root == olddp) { 2849 vref(newdp); 2850 prison0.pr_root = newdp; 2851 nrele++; 2852 } 2853 mtx_unlock(&prison0.pr_mtx); 2854 sx_slock(&allprison_lock); 2855 TAILQ_FOREACH(pr, &allprison, pr_list) { 2856 mtx_lock(&pr->pr_mtx); 2857 if (pr->pr_root == olddp) { 2858 vref(newdp); 2859 pr->pr_root = newdp; 2860 nrele++; 2861 } 2862 mtx_unlock(&pr->pr_mtx); 2863 } 2864 sx_sunlock(&allprison_lock); 2865 while (nrele--) 2866 vrele(olddp); 2867 } 2868 2869 struct filedesc_to_leader * 2870 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2871 { 2872 struct filedesc_to_leader *fdtol; 2873 2874 fdtol = malloc(sizeof(struct filedesc_to_leader), 2875 M_FILEDESC_TO_LEADER, 2876 M_WAITOK); 2877 fdtol->fdl_refcount = 1; 2878 fdtol->fdl_holdcount = 0; 2879 fdtol->fdl_wakeup = 0; 2880 fdtol->fdl_leader = leader; 2881 if (old != NULL) { 2882 FILEDESC_XLOCK(fdp); 2883 fdtol->fdl_next = old->fdl_next; 2884 fdtol->fdl_prev = old; 2885 old->fdl_next = fdtol; 2886 fdtol->fdl_next->fdl_prev = fdtol; 2887 FILEDESC_XUNLOCK(fdp); 2888 } else { 2889 fdtol->fdl_next = fdtol; 2890 fdtol->fdl_prev = fdtol; 2891 } 2892 return (fdtol); 2893 } 2894 2895 /* 2896 * Get file structures globally. 2897 */ 2898 static int 2899 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2900 { 2901 struct xfile xf; 2902 struct filedesc *fdp; 2903 struct file *fp; 2904 struct proc *p; 2905 int error, n; 2906 2907 error = sysctl_wire_old_buffer(req, 0); 2908 if (error != 0) 2909 return (error); 2910 if (req->oldptr == NULL) { 2911 n = 0; 2912 sx_slock(&allproc_lock); 2913 FOREACH_PROC_IN_SYSTEM(p) { 2914 if (p->p_state == PRS_NEW) 2915 continue; 2916 fdp = fdhold(p); 2917 if (fdp == NULL) 2918 continue; 2919 /* overestimates sparse tables. */ 2920 if (fdp->fd_lastfile > 0) 2921 n += fdp->fd_lastfile; 2922 fddrop(fdp); 2923 } 2924 sx_sunlock(&allproc_lock); 2925 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2926 } 2927 error = 0; 2928 bzero(&xf, sizeof(xf)); 2929 xf.xf_size = sizeof(xf); 2930 sx_slock(&allproc_lock); 2931 FOREACH_PROC_IN_SYSTEM(p) { 2932 PROC_LOCK(p); 2933 if (p->p_state == PRS_NEW) { 2934 PROC_UNLOCK(p); 2935 continue; 2936 } 2937 if (p_cansee(req->td, p) != 0) { 2938 PROC_UNLOCK(p); 2939 continue; 2940 } 2941 xf.xf_pid = p->p_pid; 2942 xf.xf_uid = p->p_ucred->cr_uid; 2943 PROC_UNLOCK(p); 2944 fdp = fdhold(p); 2945 if (fdp == NULL) 2946 continue; 2947 FILEDESC_SLOCK(fdp); 2948 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) { 2949 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 2950 continue; 2951 xf.xf_fd = n; 2952 xf.xf_file = fp; 2953 xf.xf_data = fp->f_data; 2954 xf.xf_vnode = fp->f_vnode; 2955 xf.xf_type = fp->f_type; 2956 xf.xf_count = fp->f_count; 2957 xf.xf_msgcount = 0; 2958 xf.xf_offset = foffset_get(fp); 2959 xf.xf_flag = fp->f_flag; 2960 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2961 if (error) 2962 break; 2963 } 2964 FILEDESC_SUNLOCK(fdp); 2965 fddrop(fdp); 2966 if (error) 2967 break; 2968 } 2969 sx_sunlock(&allproc_lock); 2970 return (error); 2971 } 2972 2973 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD, 2974 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2975 2976 #ifdef KINFO_OFILE_SIZE 2977 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 2978 #endif 2979 2980 #ifdef COMPAT_FREEBSD7 2981 static int 2982 export_vnode_for_osysctl(struct vnode *vp, int type, 2983 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 2984 { 2985 int error; 2986 char *fullpath, *freepath; 2987 2988 bzero(kif, sizeof(*kif)); 2989 kif->kf_structsize = sizeof(*kif); 2990 2991 vref(vp); 2992 kif->kf_fd = type; 2993 kif->kf_type = KF_TYPE_VNODE; 2994 /* This function only handles directories. */ 2995 if (vp->v_type != VDIR) { 2996 vrele(vp); 2997 return (ENOTDIR); 2998 } 2999 kif->kf_vnode_type = KF_VTYPE_VDIR; 3000 3001 /* 3002 * This is not a true file descriptor, so we set a bogus refcount 3003 * and offset to indicate these fields should be ignored. 3004 */ 3005 kif->kf_ref_count = -1; 3006 kif->kf_offset = -1; 3007 3008 freepath = NULL; 3009 fullpath = "-"; 3010 FILEDESC_SUNLOCK(fdp); 3011 vn_fullpath(curthread, vp, &fullpath, &freepath); 3012 vrele(vp); 3013 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3014 if (freepath != NULL) 3015 free(freepath, M_TEMP); 3016 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3017 FILEDESC_SLOCK(fdp); 3018 return (error); 3019 } 3020 3021 /* 3022 * Get per-process file descriptors for use by procstat(1), et al. 3023 */ 3024 static int 3025 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3026 { 3027 char *fullpath, *freepath; 3028 struct kinfo_ofile *kif; 3029 struct filedesc *fdp; 3030 int error, i, *name; 3031 struct shmfd *shmfd; 3032 struct socket *so; 3033 struct vnode *vp; 3034 struct ksem *ks; 3035 struct file *fp; 3036 struct proc *p; 3037 struct tty *tp; 3038 3039 name = (int *)arg1; 3040 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3041 if (error != 0) 3042 return (error); 3043 fdp = fdhold(p); 3044 PROC_UNLOCK(p); 3045 if (fdp == NULL) 3046 return (ENOENT); 3047 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3048 FILEDESC_SLOCK(fdp); 3049 if (fdp->fd_cdir != NULL) 3050 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3051 fdp, req); 3052 if (fdp->fd_rdir != NULL) 3053 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3054 fdp, req); 3055 if (fdp->fd_jdir != NULL) 3056 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3057 fdp, req); 3058 for (i = 0; i < fdp->fd_nfiles; i++) { 3059 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3060 continue; 3061 bzero(kif, sizeof(*kif)); 3062 kif->kf_structsize = sizeof(*kif); 3063 ks = NULL; 3064 vp = NULL; 3065 so = NULL; 3066 tp = NULL; 3067 shmfd = NULL; 3068 kif->kf_fd = i; 3069 3070 switch (fp->f_type) { 3071 case DTYPE_VNODE: 3072 kif->kf_type = KF_TYPE_VNODE; 3073 vp = fp->f_vnode; 3074 break; 3075 3076 case DTYPE_SOCKET: 3077 kif->kf_type = KF_TYPE_SOCKET; 3078 so = fp->f_data; 3079 break; 3080 3081 case DTYPE_PIPE: 3082 kif->kf_type = KF_TYPE_PIPE; 3083 break; 3084 3085 case DTYPE_FIFO: 3086 kif->kf_type = KF_TYPE_FIFO; 3087 vp = fp->f_vnode; 3088 break; 3089 3090 case DTYPE_KQUEUE: 3091 kif->kf_type = KF_TYPE_KQUEUE; 3092 break; 3093 3094 case DTYPE_CRYPTO: 3095 kif->kf_type = KF_TYPE_CRYPTO; 3096 break; 3097 3098 case DTYPE_MQUEUE: 3099 kif->kf_type = KF_TYPE_MQUEUE; 3100 break; 3101 3102 case DTYPE_SHM: 3103 kif->kf_type = KF_TYPE_SHM; 3104 shmfd = fp->f_data; 3105 break; 3106 3107 case DTYPE_SEM: 3108 kif->kf_type = KF_TYPE_SEM; 3109 ks = fp->f_data; 3110 break; 3111 3112 case DTYPE_PTS: 3113 kif->kf_type = KF_TYPE_PTS; 3114 tp = fp->f_data; 3115 break; 3116 3117 case DTYPE_PROCDESC: 3118 kif->kf_type = KF_TYPE_PROCDESC; 3119 break; 3120 3121 default: 3122 kif->kf_type = KF_TYPE_UNKNOWN; 3123 break; 3124 } 3125 kif->kf_ref_count = fp->f_count; 3126 if (fp->f_flag & FREAD) 3127 kif->kf_flags |= KF_FLAG_READ; 3128 if (fp->f_flag & FWRITE) 3129 kif->kf_flags |= KF_FLAG_WRITE; 3130 if (fp->f_flag & FAPPEND) 3131 kif->kf_flags |= KF_FLAG_APPEND; 3132 if (fp->f_flag & FASYNC) 3133 kif->kf_flags |= KF_FLAG_ASYNC; 3134 if (fp->f_flag & FFSYNC) 3135 kif->kf_flags |= KF_FLAG_FSYNC; 3136 if (fp->f_flag & FNONBLOCK) 3137 kif->kf_flags |= KF_FLAG_NONBLOCK; 3138 if (fp->f_flag & O_DIRECT) 3139 kif->kf_flags |= KF_FLAG_DIRECT; 3140 if (fp->f_flag & FHASLOCK) 3141 kif->kf_flags |= KF_FLAG_HASLOCK; 3142 kif->kf_offset = foffset_get(fp); 3143 if (vp != NULL) { 3144 vref(vp); 3145 switch (vp->v_type) { 3146 case VNON: 3147 kif->kf_vnode_type = KF_VTYPE_VNON; 3148 break; 3149 case VREG: 3150 kif->kf_vnode_type = KF_VTYPE_VREG; 3151 break; 3152 case VDIR: 3153 kif->kf_vnode_type = KF_VTYPE_VDIR; 3154 break; 3155 case VBLK: 3156 kif->kf_vnode_type = KF_VTYPE_VBLK; 3157 break; 3158 case VCHR: 3159 kif->kf_vnode_type = KF_VTYPE_VCHR; 3160 break; 3161 case VLNK: 3162 kif->kf_vnode_type = KF_VTYPE_VLNK; 3163 break; 3164 case VSOCK: 3165 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3166 break; 3167 case VFIFO: 3168 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3169 break; 3170 case VBAD: 3171 kif->kf_vnode_type = KF_VTYPE_VBAD; 3172 break; 3173 default: 3174 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3175 break; 3176 } 3177 /* 3178 * It is OK to drop the filedesc lock here as we will 3179 * re-validate and re-evaluate its properties when 3180 * the loop continues. 3181 */ 3182 freepath = NULL; 3183 fullpath = "-"; 3184 FILEDESC_SUNLOCK(fdp); 3185 vn_fullpath(curthread, vp, &fullpath, &freepath); 3186 vrele(vp); 3187 strlcpy(kif->kf_path, fullpath, 3188 sizeof(kif->kf_path)); 3189 if (freepath != NULL) 3190 free(freepath, M_TEMP); 3191 FILEDESC_SLOCK(fdp); 3192 } 3193 if (so != NULL) { 3194 struct sockaddr *sa; 3195 3196 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3197 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3198 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3199 free(sa, M_SONAME); 3200 } 3201 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3202 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3203 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3204 free(sa, M_SONAME); 3205 } 3206 kif->kf_sock_domain = 3207 so->so_proto->pr_domain->dom_family; 3208 kif->kf_sock_type = so->so_type; 3209 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3210 } 3211 if (tp != NULL) { 3212 strlcpy(kif->kf_path, tty_devname(tp), 3213 sizeof(kif->kf_path)); 3214 } 3215 if (shmfd != NULL) 3216 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3217 if (ks != NULL && ksem_info != NULL) 3218 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL); 3219 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3220 if (error) 3221 break; 3222 } 3223 FILEDESC_SUNLOCK(fdp); 3224 fddrop(fdp); 3225 free(kif, M_TEMP); 3226 return (0); 3227 } 3228 3229 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD, 3230 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries"); 3231 #endif /* COMPAT_FREEBSD7 */ 3232 3233 #ifdef KINFO_FILE_SIZE 3234 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3235 #endif 3236 3237 struct export_fd_buf { 3238 struct filedesc *fdp; 3239 struct sbuf *sb; 3240 ssize_t remainder; 3241 struct kinfo_file kif; 3242 }; 3243 3244 static int 3245 export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt, 3246 int64_t offset, cap_rights_t *rightsp, struct export_fd_buf *efbuf) 3247 { 3248 struct { 3249 int fflag; 3250 int kf_fflag; 3251 } fflags_table[] = { 3252 { FAPPEND, KF_FLAG_APPEND }, 3253 { FASYNC, KF_FLAG_ASYNC }, 3254 { FFSYNC, KF_FLAG_FSYNC }, 3255 { FHASLOCK, KF_FLAG_HASLOCK }, 3256 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3257 { FREAD, KF_FLAG_READ }, 3258 { FWRITE, KF_FLAG_WRITE }, 3259 { O_CREAT, KF_FLAG_CREAT }, 3260 { O_DIRECT, KF_FLAG_DIRECT }, 3261 { O_EXCL, KF_FLAG_EXCL }, 3262 { O_EXEC, KF_FLAG_EXEC }, 3263 { O_EXLOCK, KF_FLAG_EXLOCK }, 3264 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3265 { O_SHLOCK, KF_FLAG_SHLOCK }, 3266 { O_TRUNC, KF_FLAG_TRUNC } 3267 }; 3268 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3269 struct kinfo_file *kif; 3270 struct vnode *vp; 3271 int error, locked; 3272 unsigned int i; 3273 3274 if (efbuf->remainder == 0) 3275 return (0); 3276 kif = &efbuf->kif; 3277 bzero(kif, sizeof(*kif)); 3278 locked = efbuf->fdp != NULL; 3279 switch (type) { 3280 case KF_TYPE_FIFO: 3281 case KF_TYPE_VNODE: 3282 if (locked) { 3283 FILEDESC_SUNLOCK(efbuf->fdp); 3284 locked = 0; 3285 } 3286 vp = (struct vnode *)data; 3287 error = fill_vnode_info(vp, kif); 3288 vrele(vp); 3289 break; 3290 case KF_TYPE_SOCKET: 3291 error = fill_socket_info((struct socket *)data, kif); 3292 break; 3293 case KF_TYPE_PIPE: 3294 error = fill_pipe_info((struct pipe *)data, kif); 3295 break; 3296 case KF_TYPE_PTS: 3297 error = fill_pts_info((struct tty *)data, kif); 3298 break; 3299 case KF_TYPE_PROCDESC: 3300 error = fill_procdesc_info((struct procdesc *)data, kif); 3301 break; 3302 case KF_TYPE_SEM: 3303 error = fill_sem_info((struct file *)data, kif); 3304 break; 3305 case KF_TYPE_SHM: 3306 error = fill_shm_info((struct file *)data, kif); 3307 break; 3308 default: 3309 error = 0; 3310 } 3311 if (error == 0) 3312 kif->kf_status |= KF_ATTR_VALID; 3313 3314 /* 3315 * Translate file access flags. 3316 */ 3317 for (i = 0; i < NFFLAGS; i++) 3318 if (fflags & fflags_table[i].fflag) 3319 kif->kf_flags |= fflags_table[i].kf_fflag; 3320 if (rightsp != NULL) 3321 kif->kf_cap_rights = *rightsp; 3322 else 3323 cap_rights_init(&kif->kf_cap_rights); 3324 kif->kf_fd = fd; 3325 kif->kf_type = type; 3326 kif->kf_ref_count = refcnt; 3327 kif->kf_offset = offset; 3328 /* Pack record size down */ 3329 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3330 strlen(kif->kf_path) + 1; 3331 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3332 if (efbuf->remainder != -1) { 3333 if (efbuf->remainder < kif->kf_structsize) { 3334 /* Terminate export. */ 3335 efbuf->remainder = 0; 3336 if (efbuf->fdp != NULL && !locked) 3337 FILEDESC_SLOCK(efbuf->fdp); 3338 return (0); 3339 } 3340 efbuf->remainder -= kif->kf_structsize; 3341 } 3342 if (locked) 3343 FILEDESC_SUNLOCK(efbuf->fdp); 3344 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize); 3345 if (efbuf->fdp != NULL) 3346 FILEDESC_SLOCK(efbuf->fdp); 3347 return (error); 3348 } 3349 3350 /* 3351 * Store a process file descriptor information to sbuf. 3352 * 3353 * Takes a locked proc as argument, and returns with the proc unlocked. 3354 */ 3355 int 3356 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3357 { 3358 struct file *fp; 3359 struct filedesc *fdp; 3360 struct export_fd_buf *efbuf; 3361 struct vnode *cttyvp, *textvp, *tracevp; 3362 int64_t offset; 3363 void *data; 3364 int error, i; 3365 int type, refcnt, fflags; 3366 cap_rights_t rights; 3367 3368 PROC_LOCK_ASSERT(p, MA_OWNED); 3369 3370 /* ktrace vnode */ 3371 tracevp = p->p_tracevp; 3372 if (tracevp != NULL) 3373 vref(tracevp); 3374 /* text vnode */ 3375 textvp = p->p_textvp; 3376 if (textvp != NULL) 3377 vref(textvp); 3378 /* Controlling tty. */ 3379 cttyvp = NULL; 3380 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3381 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3382 if (cttyvp != NULL) 3383 vref(cttyvp); 3384 } 3385 fdp = fdhold(p); 3386 PROC_UNLOCK(p); 3387 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3388 efbuf->fdp = NULL; 3389 efbuf->sb = sb; 3390 efbuf->remainder = maxlen; 3391 if (tracevp != NULL) 3392 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3393 FREAD | FWRITE, -1, -1, NULL, efbuf); 3394 if (textvp != NULL) 3395 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3396 FREAD, -1, -1, NULL, efbuf); 3397 if (cttyvp != NULL) 3398 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3399 FREAD | FWRITE, -1, -1, NULL, efbuf); 3400 error = 0; 3401 if (fdp == NULL) 3402 goto fail; 3403 efbuf->fdp = fdp; 3404 FILEDESC_SLOCK(fdp); 3405 /* working directory */ 3406 if (fdp->fd_cdir != NULL) { 3407 vref(fdp->fd_cdir); 3408 data = fdp->fd_cdir; 3409 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3410 FREAD, -1, -1, NULL, efbuf); 3411 } 3412 /* root directory */ 3413 if (fdp->fd_rdir != NULL) { 3414 vref(fdp->fd_rdir); 3415 data = fdp->fd_rdir; 3416 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3417 FREAD, -1, -1, NULL, efbuf); 3418 } 3419 /* jail directory */ 3420 if (fdp->fd_jdir != NULL) { 3421 vref(fdp->fd_jdir); 3422 data = fdp->fd_jdir; 3423 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3424 FREAD, -1, -1, NULL, efbuf); 3425 } 3426 for (i = 0; i < fdp->fd_nfiles; i++) { 3427 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3428 continue; 3429 data = NULL; 3430 #ifdef CAPABILITIES 3431 rights = *cap_rights(fdp, i); 3432 #else /* !CAPABILITIES */ 3433 cap_rights_init(&rights); 3434 #endif 3435 switch (fp->f_type) { 3436 case DTYPE_VNODE: 3437 type = KF_TYPE_VNODE; 3438 vref(fp->f_vnode); 3439 data = fp->f_vnode; 3440 break; 3441 3442 case DTYPE_SOCKET: 3443 type = KF_TYPE_SOCKET; 3444 data = fp->f_data; 3445 break; 3446 3447 case DTYPE_PIPE: 3448 type = KF_TYPE_PIPE; 3449 data = fp->f_data; 3450 break; 3451 3452 case DTYPE_FIFO: 3453 type = KF_TYPE_FIFO; 3454 vref(fp->f_vnode); 3455 data = fp->f_vnode; 3456 break; 3457 3458 case DTYPE_KQUEUE: 3459 type = KF_TYPE_KQUEUE; 3460 break; 3461 3462 case DTYPE_CRYPTO: 3463 type = KF_TYPE_CRYPTO; 3464 break; 3465 3466 case DTYPE_MQUEUE: 3467 type = KF_TYPE_MQUEUE; 3468 break; 3469 3470 case DTYPE_SHM: 3471 type = KF_TYPE_SHM; 3472 data = fp; 3473 break; 3474 3475 case DTYPE_SEM: 3476 type = KF_TYPE_SEM; 3477 data = fp; 3478 break; 3479 3480 case DTYPE_PTS: 3481 type = KF_TYPE_PTS; 3482 data = fp->f_data; 3483 break; 3484 3485 case DTYPE_PROCDESC: 3486 type = KF_TYPE_PROCDESC; 3487 data = fp->f_data; 3488 break; 3489 3490 default: 3491 type = KF_TYPE_UNKNOWN; 3492 break; 3493 } 3494 refcnt = fp->f_count; 3495 fflags = fp->f_flag; 3496 offset = foffset_get(fp); 3497 3498 /* 3499 * Create sysctl entry. 3500 * It is OK to drop the filedesc lock here as we will 3501 * re-validate and re-evaluate its properties when 3502 * the loop continues. 3503 */ 3504 error = export_fd_to_sb(data, type, i, fflags, refcnt, 3505 offset, &rights, efbuf); 3506 if (error != 0) 3507 break; 3508 } 3509 FILEDESC_SUNLOCK(fdp); 3510 fddrop(fdp); 3511 fail: 3512 free(efbuf, M_TEMP); 3513 return (error); 3514 } 3515 3516 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3517 3518 /* 3519 * Get per-process file descriptors for use by procstat(1), et al. 3520 */ 3521 static int 3522 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3523 { 3524 struct sbuf sb; 3525 struct proc *p; 3526 ssize_t maxlen; 3527 int error, error2, *name; 3528 3529 name = (int *)arg1; 3530 3531 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3532 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3533 if (error != 0) { 3534 sbuf_delete(&sb); 3535 return (error); 3536 } 3537 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3538 error = kern_proc_filedesc_out(p, &sb, maxlen); 3539 error2 = sbuf_finish(&sb); 3540 sbuf_delete(&sb); 3541 return (error != 0 ? error : error2); 3542 } 3543 3544 int 3545 vntype_to_kinfo(int vtype) 3546 { 3547 struct { 3548 int vtype; 3549 int kf_vtype; 3550 } vtypes_table[] = { 3551 { VBAD, KF_VTYPE_VBAD }, 3552 { VBLK, KF_VTYPE_VBLK }, 3553 { VCHR, KF_VTYPE_VCHR }, 3554 { VDIR, KF_VTYPE_VDIR }, 3555 { VFIFO, KF_VTYPE_VFIFO }, 3556 { VLNK, KF_VTYPE_VLNK }, 3557 { VNON, KF_VTYPE_VNON }, 3558 { VREG, KF_VTYPE_VREG }, 3559 { VSOCK, KF_VTYPE_VSOCK } 3560 }; 3561 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3562 unsigned int i; 3563 3564 /* 3565 * Perform vtype translation. 3566 */ 3567 for (i = 0; i < NVTYPES; i++) 3568 if (vtypes_table[i].vtype == vtype) 3569 break; 3570 if (i < NVTYPES) 3571 return (vtypes_table[i].kf_vtype); 3572 3573 return (KF_VTYPE_UNKNOWN); 3574 } 3575 3576 static int 3577 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3578 { 3579 struct vattr va; 3580 char *fullpath, *freepath; 3581 int error; 3582 3583 if (vp == NULL) 3584 return (1); 3585 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3586 freepath = NULL; 3587 fullpath = "-"; 3588 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3589 if (error == 0) { 3590 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3591 } 3592 if (freepath != NULL) 3593 free(freepath, M_TEMP); 3594 3595 /* 3596 * Retrieve vnode attributes. 3597 */ 3598 va.va_fsid = VNOVAL; 3599 va.va_rdev = NODEV; 3600 vn_lock(vp, LK_SHARED | LK_RETRY); 3601 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3602 VOP_UNLOCK(vp, 0); 3603 if (error != 0) 3604 return (error); 3605 if (va.va_fsid != VNOVAL) 3606 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3607 else 3608 kif->kf_un.kf_file.kf_file_fsid = 3609 vp->v_mount->mnt_stat.f_fsid.val[0]; 3610 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3611 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3612 kif->kf_un.kf_file.kf_file_size = va.va_size; 3613 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3614 return (0); 3615 } 3616 3617 static int 3618 fill_socket_info(struct socket *so, struct kinfo_file *kif) 3619 { 3620 struct sockaddr *sa; 3621 struct inpcb *inpcb; 3622 struct unpcb *unpcb; 3623 int error; 3624 3625 if (so == NULL) 3626 return (1); 3627 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3628 kif->kf_sock_type = so->so_type; 3629 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3630 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3631 switch(kif->kf_sock_domain) { 3632 case AF_INET: 3633 case AF_INET6: 3634 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3635 if (so->so_pcb != NULL) { 3636 inpcb = (struct inpcb *)(so->so_pcb); 3637 kif->kf_un.kf_sock.kf_sock_inpcb = 3638 (uintptr_t)inpcb->inp_ppcb; 3639 } 3640 } 3641 break; 3642 case AF_UNIX: 3643 if (so->so_pcb != NULL) { 3644 unpcb = (struct unpcb *)(so->so_pcb); 3645 if (unpcb->unp_conn) { 3646 kif->kf_un.kf_sock.kf_sock_unpconn = 3647 (uintptr_t)unpcb->unp_conn; 3648 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3649 so->so_rcv.sb_state; 3650 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3651 so->so_snd.sb_state; 3652 } 3653 } 3654 break; 3655 } 3656 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3657 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3658 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3659 free(sa, M_SONAME); 3660 } 3661 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3662 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3663 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3664 free(sa, M_SONAME); 3665 } 3666 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3667 sizeof(kif->kf_path)); 3668 return (0); 3669 } 3670 3671 static int 3672 fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3673 { 3674 3675 if (tp == NULL) 3676 return (1); 3677 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3678 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3679 return (0); 3680 } 3681 3682 static int 3683 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3684 { 3685 3686 if (pi == NULL) 3687 return (1); 3688 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3689 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3690 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3691 return (0); 3692 } 3693 3694 static int 3695 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3696 { 3697 3698 if (pdp == NULL) 3699 return (1); 3700 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3701 return (0); 3702 } 3703 3704 static int 3705 fill_sem_info(struct file *fp, struct kinfo_file *kif) 3706 { 3707 struct thread *td; 3708 struct stat sb; 3709 3710 td = curthread; 3711 if (fp->f_data == NULL) 3712 return (1); 3713 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3714 return (1); 3715 if (ksem_info == NULL) 3716 return (1); 3717 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path), 3718 &kif->kf_un.kf_sem.kf_sem_value); 3719 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode; 3720 return (0); 3721 } 3722 3723 static int 3724 fill_shm_info(struct file *fp, struct kinfo_file *kif) 3725 { 3726 struct thread *td; 3727 struct stat sb; 3728 3729 td = curthread; 3730 if (fp->f_data == NULL) 3731 return (1); 3732 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3733 return (1); 3734 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3735 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3736 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3737 return (0); 3738 } 3739 3740 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD, 3741 sysctl_kern_proc_filedesc, "Process filedesc entries"); 3742 3743 #ifdef DDB 3744 /* 3745 * For the purposes of debugging, generate a human-readable string for the 3746 * file type. 3747 */ 3748 static const char * 3749 file_type_to_name(short type) 3750 { 3751 3752 switch (type) { 3753 case 0: 3754 return ("zero"); 3755 case DTYPE_VNODE: 3756 return ("vnod"); 3757 case DTYPE_SOCKET: 3758 return ("sock"); 3759 case DTYPE_PIPE: 3760 return ("pipe"); 3761 case DTYPE_FIFO: 3762 return ("fifo"); 3763 case DTYPE_KQUEUE: 3764 return ("kque"); 3765 case DTYPE_CRYPTO: 3766 return ("crpt"); 3767 case DTYPE_MQUEUE: 3768 return ("mque"); 3769 case DTYPE_SHM: 3770 return ("shm"); 3771 case DTYPE_SEM: 3772 return ("ksem"); 3773 default: 3774 return ("unkn"); 3775 } 3776 } 3777 3778 /* 3779 * For the purposes of debugging, identify a process (if any, perhaps one of 3780 * many) that references the passed file in its file descriptor array. Return 3781 * NULL if none. 3782 */ 3783 static struct proc * 3784 file_to_first_proc(struct file *fp) 3785 { 3786 struct filedesc *fdp; 3787 struct proc *p; 3788 int n; 3789 3790 FOREACH_PROC_IN_SYSTEM(p) { 3791 if (p->p_state == PRS_NEW) 3792 continue; 3793 fdp = p->p_fd; 3794 if (fdp == NULL) 3795 continue; 3796 for (n = 0; n < fdp->fd_nfiles; n++) { 3797 if (fp == fdp->fd_ofiles[n].fde_file) 3798 return (p); 3799 } 3800 } 3801 return (NULL); 3802 } 3803 3804 static void 3805 db_print_file(struct file *fp, int header) 3806 { 3807 struct proc *p; 3808 3809 if (header) 3810 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3811 "File", "Type", "Data", "Flag", "GCFl", "Count", 3812 "MCount", "Vnode", "FPID", "FCmd"); 3813 p = file_to_first_proc(fp); 3814 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3815 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3816 0, fp->f_count, 0, fp->f_vnode, 3817 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3818 } 3819 3820 DB_SHOW_COMMAND(file, db_show_file) 3821 { 3822 struct file *fp; 3823 3824 if (!have_addr) { 3825 db_printf("usage: show file <addr>\n"); 3826 return; 3827 } 3828 fp = (struct file *)addr; 3829 db_print_file(fp, 1); 3830 } 3831 3832 DB_SHOW_COMMAND(files, db_show_files) 3833 { 3834 struct filedesc *fdp; 3835 struct file *fp; 3836 struct proc *p; 3837 int header; 3838 int n; 3839 3840 header = 1; 3841 FOREACH_PROC_IN_SYSTEM(p) { 3842 if (p->p_state == PRS_NEW) 3843 continue; 3844 if ((fdp = p->p_fd) == NULL) 3845 continue; 3846 for (n = 0; n < fdp->fd_nfiles; ++n) { 3847 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3848 continue; 3849 db_print_file(fp, header); 3850 header = 0; 3851 } 3852 } 3853 } 3854 #endif 3855 3856 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3857 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3858 3859 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3860 &maxfiles, 0, "Maximum number of files"); 3861 3862 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3863 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3864 3865 /* ARGSUSED*/ 3866 static void 3867 filelistinit(void *dummy) 3868 { 3869 3870 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3871 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3872 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3873 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3874 } 3875 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3876 3877 /*-------------------------------------------------------------------*/ 3878 3879 static int 3880 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3881 int flags, struct thread *td) 3882 { 3883 3884 return (EBADF); 3885 } 3886 3887 static int 3888 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3889 struct thread *td) 3890 { 3891 3892 return (EINVAL); 3893 } 3894 3895 static int 3896 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3897 struct thread *td) 3898 { 3899 3900 return (EBADF); 3901 } 3902 3903 static int 3904 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3905 struct thread *td) 3906 { 3907 3908 return (0); 3909 } 3910 3911 static int 3912 badfo_kqfilter(struct file *fp, struct knote *kn) 3913 { 3914 3915 return (EBADF); 3916 } 3917 3918 static int 3919 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3920 struct thread *td) 3921 { 3922 3923 return (EBADF); 3924 } 3925 3926 static int 3927 badfo_close(struct file *fp, struct thread *td) 3928 { 3929 3930 return (EBADF); 3931 } 3932 3933 static int 3934 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3935 struct thread *td) 3936 { 3937 3938 return (EBADF); 3939 } 3940 3941 static int 3942 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3943 struct thread *td) 3944 { 3945 3946 return (EBADF); 3947 } 3948 3949 static int 3950 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3951 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3952 int kflags, struct sendfile_sync *sfs, struct thread *td) 3953 { 3954 3955 return (EBADF); 3956 } 3957 3958 struct fileops badfileops = { 3959 .fo_read = badfo_readwrite, 3960 .fo_write = badfo_readwrite, 3961 .fo_truncate = badfo_truncate, 3962 .fo_ioctl = badfo_ioctl, 3963 .fo_poll = badfo_poll, 3964 .fo_kqfilter = badfo_kqfilter, 3965 .fo_stat = badfo_stat, 3966 .fo_close = badfo_close, 3967 .fo_chmod = badfo_chmod, 3968 .fo_chown = badfo_chown, 3969 .fo_sendfile = badfo_sendfile, 3970 }; 3971 3972 int 3973 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3974 struct thread *td) 3975 { 3976 3977 return (EINVAL); 3978 } 3979 3980 int 3981 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3982 struct thread *td) 3983 { 3984 3985 return (EINVAL); 3986 } 3987 3988 int 3989 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3990 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3991 int kflags, struct sendfile_sync *sfs, struct thread *td) 3992 { 3993 3994 return (EINVAL); 3995 } 3996 3997 /*-------------------------------------------------------------------*/ 3998 3999 /* 4000 * File Descriptor pseudo-device driver (/dev/fd/). 4001 * 4002 * Opening minor device N dup()s the file (if any) connected to file 4003 * descriptor N belonging to the calling process. Note that this driver 4004 * consists of only the ``open()'' routine, because all subsequent 4005 * references to this file will be direct to the other driver. 4006 * 4007 * XXX: we could give this one a cloning event handler if necessary. 4008 */ 4009 4010 /* ARGSUSED */ 4011 static int 4012 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 4013 { 4014 4015 /* 4016 * XXX Kludge: set curthread->td_dupfd to contain the value of the 4017 * the file descriptor being sought for duplication. The error 4018 * return ensures that the vnode for this device will be released 4019 * by vn_open. Open will detect this special error and take the 4020 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 4021 * will simply report the error. 4022 */ 4023 td->td_dupfd = dev2unit(dev); 4024 return (ENODEV); 4025 } 4026 4027 static struct cdevsw fildesc_cdevsw = { 4028 .d_version = D_VERSION, 4029 .d_open = fdopen, 4030 .d_name = "FD", 4031 }; 4032 4033 static void 4034 fildesc_drvinit(void *unused) 4035 { 4036 struct cdev *dev; 4037 4038 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4039 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4040 make_dev_alias(dev, "stdin"); 4041 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4042 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4043 make_dev_alias(dev, "stdout"); 4044 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4045 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4046 make_dev_alias(dev, "stderr"); 4047 } 4048 4049 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4050