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 #include "opt_procdesc.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 49 #include <sys/capability.h> 50 #include <sys/conf.h> 51 #include <sys/domain.h> 52 #include <sys/fcntl.h> 53 #include <sys/file.h> 54 #include <sys/filedesc.h> 55 #include <sys/filio.h> 56 #include <sys/jail.h> 57 #include <sys/kernel.h> 58 #include <sys/ksem.h> 59 #include <sys/limits.h> 60 #include <sys/lock.h> 61 #include <sys/malloc.h> 62 #include <sys/mman.h> 63 #include <sys/mount.h> 64 #include <sys/mqueue.h> 65 #include <sys/mutex.h> 66 #include <sys/namei.h> 67 #include <sys/selinfo.h> 68 #include <sys/pipe.h> 69 #include <sys/priv.h> 70 #include <sys/proc.h> 71 #include <sys/procdesc.h> 72 #include <sys/protosw.h> 73 #include <sys/racct.h> 74 #include <sys/resourcevar.h> 75 #include <sys/sbuf.h> 76 #include <sys/signalvar.h> 77 #include <sys/socketvar.h> 78 #include <sys/stat.h> 79 #include <sys/sx.h> 80 #include <sys/syscallsubr.h> 81 #include <sys/sysctl.h> 82 #include <sys/sysproto.h> 83 #include <sys/tty.h> 84 #include <sys/unistd.h> 85 #include <sys/un.h> 86 #include <sys/unpcb.h> 87 #include <sys/user.h> 88 #include <sys/vnode.h> 89 #ifdef KTRACE 90 #include <sys/ktrace.h> 91 #endif 92 93 #include <net/vnet.h> 94 95 #include <netinet/in.h> 96 #include <netinet/in_pcb.h> 97 98 #include <security/audit/audit.h> 99 100 #include <vm/uma.h> 101 #include <vm/vm.h> 102 103 #include <ddb/ddb.h> 104 105 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 106 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 107 "file desc to leader structures"); 108 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 109 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 110 111 MALLOC_DECLARE(M_FADVISE); 112 113 static uma_zone_t file_zone; 114 115 void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value); 116 117 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 118 struct thread *td, int holdleaders); 119 static int fd_first_free(struct filedesc *fdp, int low, int size); 120 static int fd_last_used(struct filedesc *fdp, int size); 121 static void fdgrowtable(struct filedesc *fdp, int nfd); 122 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 123 static void fdunused(struct filedesc *fdp, int fd); 124 static void fdused(struct filedesc *fdp, int fd); 125 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); 126 static int fill_procdesc_info(struct procdesc *pdp, 127 struct kinfo_file *kif); 128 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif); 129 static int fill_sem_info(struct file *fp, struct kinfo_file *kif); 130 static int fill_shm_info(struct file *fp, struct kinfo_file *kif); 131 static int fill_socket_info(struct socket *so, struct kinfo_file *kif); 132 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); 133 static int getmaxfd(struct proc *p); 134 135 /* 136 * Each process has: 137 * 138 * - An array of open file descriptors (fd_ofiles) 139 * - An array of file flags (fd_ofileflags) 140 * - A bitmap recording which descriptors are in use (fd_map) 141 * 142 * A process starts out with NDFILE descriptors. The value of NDFILE has 143 * been selected based the historical limit of 20 open files, and an 144 * assumption that the majority of processes, especially short-lived 145 * processes like shells, will never need more. 146 * 147 * If this initial allocation is exhausted, a larger descriptor table and 148 * map are allocated dynamically, and the pointers in the process's struct 149 * filedesc are updated to point to those. This is repeated every time 150 * the process runs out of file descriptors (provided it hasn't hit its 151 * resource limit). 152 * 153 * Since threads may hold references to individual descriptor table 154 * entries, the tables are never freed. Instead, they are placed on a 155 * linked list and freed only when the struct filedesc is released. 156 */ 157 #define NDFILE 20 158 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 159 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 160 #define NDSLOT(x) ((x) / NDENTRIES) 161 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 162 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 163 164 /* 165 * SLIST entry used to keep track of ofiles which must be reclaimed when 166 * the process exits. 167 */ 168 struct freetable { 169 struct filedescent *ft_table; 170 SLIST_ENTRY(freetable) ft_next; 171 }; 172 173 /* 174 * Initial allocation: a filedesc structure + the head of SLIST used to 175 * keep track of old ofiles + enough space for NDFILE descriptors. 176 */ 177 struct filedesc0 { 178 struct filedesc fd_fd; 179 SLIST_HEAD(, freetable) fd_free; 180 struct filedescent fd_dfiles[NDFILE]; 181 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 182 }; 183 184 /* 185 * Descriptor management. 186 */ 187 volatile int openfiles; /* actual number of open files */ 188 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 189 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 190 191 /* A mutex to protect the association between a proc and filedesc. */ 192 static struct mtx fdesc_mtx; 193 194 /* 195 * If low >= size, just return low. Otherwise find the first zero bit in the 196 * given bitmap, starting at low and not exceeding size - 1. Return size if 197 * not found. 198 */ 199 static int 200 fd_first_free(struct filedesc *fdp, int low, int size) 201 { 202 NDSLOTTYPE *map = fdp->fd_map; 203 NDSLOTTYPE mask; 204 int off, maxoff; 205 206 if (low >= size) 207 return (low); 208 209 off = NDSLOT(low); 210 if (low % NDENTRIES) { 211 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 212 if ((mask &= ~map[off]) != 0UL) 213 return (off * NDENTRIES + ffsl(mask) - 1); 214 ++off; 215 } 216 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 217 if (map[off] != ~0UL) 218 return (off * NDENTRIES + ffsl(~map[off]) - 1); 219 return (size); 220 } 221 222 /* 223 * Find the highest non-zero bit in the given bitmap, starting at 0 and 224 * not exceeding size - 1. Return -1 if not found. 225 */ 226 static int 227 fd_last_used(struct filedesc *fdp, int size) 228 { 229 NDSLOTTYPE *map = fdp->fd_map; 230 NDSLOTTYPE mask; 231 int off, minoff; 232 233 off = NDSLOT(size); 234 if (size % NDENTRIES) { 235 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 236 if ((mask &= map[off]) != 0) 237 return (off * NDENTRIES + flsl(mask) - 1); 238 --off; 239 } 240 for (minoff = NDSLOT(0); off >= minoff; --off) 241 if (map[off] != 0) 242 return (off * NDENTRIES + flsl(map[off]) - 1); 243 return (-1); 244 } 245 246 static int 247 fdisused(struct filedesc *fdp, int fd) 248 { 249 250 FILEDESC_LOCK_ASSERT(fdp); 251 252 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 253 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 254 255 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 256 } 257 258 /* 259 * Mark a file descriptor as used. 260 */ 261 static void 262 fdused(struct filedesc *fdp, int fd) 263 { 264 265 FILEDESC_XLOCK_ASSERT(fdp); 266 267 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 268 269 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 270 if (fd > fdp->fd_lastfile) 271 fdp->fd_lastfile = fd; 272 if (fd == fdp->fd_freefile) 273 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 274 } 275 276 /* 277 * Mark a file descriptor as unused. 278 */ 279 static void 280 fdunused(struct filedesc *fdp, int fd) 281 { 282 283 FILEDESC_XLOCK_ASSERT(fdp); 284 285 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 286 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 287 ("fd=%d is still in use", fd)); 288 289 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 290 if (fd < fdp->fd_freefile) 291 fdp->fd_freefile = fd; 292 if (fd == fdp->fd_lastfile) 293 fdp->fd_lastfile = fd_last_used(fdp, fd); 294 } 295 296 /* 297 * Free a file descriptor. 298 */ 299 static inline void 300 fdfree(struct filedesc *fdp, int fd) 301 { 302 struct filedescent *fde; 303 304 fde = &fdp->fd_ofiles[fd]; 305 filecaps_free(&fde->fde_caps); 306 bzero(fde, sizeof(*fde)); 307 fdunused(fdp, fd); 308 } 309 310 /* 311 * System calls on descriptors. 312 */ 313 #ifndef _SYS_SYSPROTO_H_ 314 struct getdtablesize_args { 315 int dummy; 316 }; 317 #endif 318 /* ARGSUSED */ 319 int 320 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 321 { 322 struct proc *p = td->td_proc; 323 uint64_t lim; 324 325 PROC_LOCK(p); 326 td->td_retval[0] = 327 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 328 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 329 PROC_UNLOCK(p); 330 if (lim < td->td_retval[0]) 331 td->td_retval[0] = lim; 332 return (0); 333 } 334 335 /* 336 * Duplicate a file descriptor to a particular value. 337 * 338 * Note: keep in mind that a potential race condition exists when closing 339 * descriptors from a shared descriptor table (via rfork). 340 */ 341 #ifndef _SYS_SYSPROTO_H_ 342 struct dup2_args { 343 u_int from; 344 u_int to; 345 }; 346 #endif 347 /* ARGSUSED */ 348 int 349 sys_dup2(struct thread *td, struct dup2_args *uap) 350 { 351 352 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 353 td->td_retval)); 354 } 355 356 /* 357 * Duplicate a file descriptor. 358 */ 359 #ifndef _SYS_SYSPROTO_H_ 360 struct dup_args { 361 u_int fd; 362 }; 363 #endif 364 /* ARGSUSED */ 365 int 366 sys_dup(struct thread *td, struct dup_args *uap) 367 { 368 369 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 370 } 371 372 /* 373 * The file control system call. 374 */ 375 #ifndef _SYS_SYSPROTO_H_ 376 struct fcntl_args { 377 int fd; 378 int cmd; 379 long arg; 380 }; 381 #endif 382 /* ARGSUSED */ 383 int 384 sys_fcntl(struct thread *td, struct fcntl_args *uap) 385 { 386 struct flock fl; 387 struct __oflock ofl; 388 intptr_t arg; 389 int error; 390 int cmd; 391 392 error = 0; 393 cmd = uap->cmd; 394 switch (uap->cmd) { 395 case F_OGETLK: 396 case F_OSETLK: 397 case F_OSETLKW: 398 /* 399 * Convert old flock structure to new. 400 */ 401 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 402 fl.l_start = ofl.l_start; 403 fl.l_len = ofl.l_len; 404 fl.l_pid = ofl.l_pid; 405 fl.l_type = ofl.l_type; 406 fl.l_whence = ofl.l_whence; 407 fl.l_sysid = 0; 408 409 switch (uap->cmd) { 410 case F_OGETLK: 411 cmd = F_GETLK; 412 break; 413 case F_OSETLK: 414 cmd = F_SETLK; 415 break; 416 case F_OSETLKW: 417 cmd = F_SETLKW; 418 break; 419 } 420 arg = (intptr_t)&fl; 421 break; 422 case F_GETLK: 423 case F_SETLK: 424 case F_SETLKW: 425 case F_SETLK_REMOTE: 426 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 427 arg = (intptr_t)&fl; 428 break; 429 default: 430 arg = uap->arg; 431 break; 432 } 433 if (error) 434 return (error); 435 error = kern_fcntl(td, uap->fd, cmd, arg); 436 if (error) 437 return (error); 438 if (uap->cmd == F_OGETLK) { 439 ofl.l_start = fl.l_start; 440 ofl.l_len = fl.l_len; 441 ofl.l_pid = fl.l_pid; 442 ofl.l_type = fl.l_type; 443 ofl.l_whence = fl.l_whence; 444 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 445 } else if (uap->cmd == F_GETLK) { 446 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 447 } 448 return (error); 449 } 450 451 int 452 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 453 { 454 struct filedesc *fdp; 455 struct flock *flp; 456 struct file *fp, *fp2; 457 struct filedescent *fde; 458 struct proc *p; 459 struct vnode *vp; 460 cap_rights_t rights; 461 int error, flg, tmp; 462 u_int old, new; 463 uint64_t bsize; 464 off_t foffset; 465 466 error = 0; 467 flg = F_POSIX; 468 p = td->td_proc; 469 fdp = p->p_fd; 470 471 switch (cmd) { 472 case F_DUPFD: 473 tmp = arg; 474 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 475 break; 476 477 case F_DUPFD_CLOEXEC: 478 tmp = arg; 479 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 480 td->td_retval); 481 break; 482 483 case F_DUP2FD: 484 tmp = arg; 485 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 486 break; 487 488 case F_DUP2FD_CLOEXEC: 489 tmp = arg; 490 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 491 td->td_retval); 492 break; 493 494 case F_GETFD: 495 FILEDESC_SLOCK(fdp); 496 if ((fp = fget_locked(fdp, fd)) == NULL) { 497 FILEDESC_SUNLOCK(fdp); 498 error = EBADF; 499 break; 500 } 501 fde = &fdp->fd_ofiles[fd]; 502 td->td_retval[0] = 503 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 504 FILEDESC_SUNLOCK(fdp); 505 break; 506 507 case F_SETFD: 508 FILEDESC_XLOCK(fdp); 509 if ((fp = fget_locked(fdp, fd)) == NULL) { 510 FILEDESC_XUNLOCK(fdp); 511 error = EBADF; 512 break; 513 } 514 fde = &fdp->fd_ofiles[fd]; 515 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 516 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 517 FILEDESC_XUNLOCK(fdp); 518 break; 519 520 case F_GETFL: 521 error = fget_unlocked(fdp, fd, 522 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp, NULL); 523 if (error != 0) 524 break; 525 td->td_retval[0] = OFLAGS(fp->f_flag); 526 fdrop(fp, td); 527 break; 528 529 case F_SETFL: 530 error = fget_unlocked(fdp, fd, 531 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp, NULL); 532 if (error != 0) 533 break; 534 do { 535 tmp = flg = fp->f_flag; 536 tmp &= ~FCNTLFLAGS; 537 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 538 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 539 tmp = fp->f_flag & FNONBLOCK; 540 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 541 if (error != 0) { 542 fdrop(fp, td); 543 break; 544 } 545 tmp = fp->f_flag & FASYNC; 546 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 547 if (error == 0) { 548 fdrop(fp, td); 549 break; 550 } 551 atomic_clear_int(&fp->f_flag, FNONBLOCK); 552 tmp = 0; 553 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 554 fdrop(fp, td); 555 break; 556 557 case F_GETOWN: 558 error = fget_unlocked(fdp, fd, 559 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp, NULL); 560 if (error != 0) 561 break; 562 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 563 if (error == 0) 564 td->td_retval[0] = tmp; 565 fdrop(fp, td); 566 break; 567 568 case F_SETOWN: 569 error = fget_unlocked(fdp, fd, 570 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp, NULL); 571 if (error != 0) 572 break; 573 tmp = arg; 574 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 575 fdrop(fp, td); 576 break; 577 578 case F_SETLK_REMOTE: 579 error = priv_check(td, PRIV_NFS_LOCKD); 580 if (error) 581 return (error); 582 flg = F_REMOTE; 583 goto do_setlk; 584 585 case F_SETLKW: 586 flg |= F_WAIT; 587 /* FALLTHROUGH F_SETLK */ 588 589 case F_SETLK: 590 do_setlk: 591 cap_rights_init(&rights, CAP_FLOCK); 592 error = fget_unlocked(fdp, fd, &rights, 0, &fp, NULL); 593 if (error != 0) 594 break; 595 if (fp->f_type != DTYPE_VNODE) { 596 error = EBADF; 597 fdrop(fp, td); 598 break; 599 } 600 601 flp = (struct flock *)arg; 602 if (flp->l_whence == SEEK_CUR) { 603 foffset = foffset_get(fp); 604 if (foffset < 0 || 605 (flp->l_start > 0 && 606 foffset > OFF_MAX - flp->l_start)) { 607 FILEDESC_SUNLOCK(fdp); 608 error = EOVERFLOW; 609 fdrop(fp, td); 610 break; 611 } 612 flp->l_start += foffset; 613 } 614 615 vp = fp->f_vnode; 616 switch (flp->l_type) { 617 case F_RDLCK: 618 if ((fp->f_flag & FREAD) == 0) { 619 error = EBADF; 620 break; 621 } 622 PROC_LOCK(p->p_leader); 623 p->p_leader->p_flag |= P_ADVLOCK; 624 PROC_UNLOCK(p->p_leader); 625 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 626 flp, flg); 627 break; 628 case F_WRLCK: 629 if ((fp->f_flag & FWRITE) == 0) { 630 error = EBADF; 631 break; 632 } 633 PROC_LOCK(p->p_leader); 634 p->p_leader->p_flag |= P_ADVLOCK; 635 PROC_UNLOCK(p->p_leader); 636 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 637 flp, flg); 638 break; 639 case F_UNLCK: 640 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 641 flp, flg); 642 break; 643 case F_UNLCKSYS: 644 /* 645 * Temporary api for testing remote lock 646 * infrastructure. 647 */ 648 if (flg != F_REMOTE) { 649 error = EINVAL; 650 break; 651 } 652 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 653 F_UNLCKSYS, flp, flg); 654 break; 655 default: 656 error = EINVAL; 657 break; 658 } 659 if (error != 0 || flp->l_type == F_UNLCK || 660 flp->l_type == F_UNLCKSYS) { 661 fdrop(fp, td); 662 break; 663 } 664 665 /* 666 * Check for a race with close. 667 * 668 * The vnode is now advisory locked (or unlocked, but this case 669 * is not really important) as the caller requested. 670 * We had to drop the filedesc lock, so we need to recheck if 671 * the descriptor is still valid, because if it was closed 672 * in the meantime we need to remove advisory lock from the 673 * vnode - close on any descriptor leading to an advisory 674 * locked vnode, removes that lock. 675 * We will return 0 on purpose in that case, as the result of 676 * successful advisory lock might have been externally visible 677 * already. This is fine - effectively we pretend to the caller 678 * that the closing thread was a bit slower and that the 679 * advisory lock succeeded before the close. 680 */ 681 error = fget_unlocked(fdp, fd, &rights, 0, &fp2, NULL); 682 if (error != 0) { 683 fdrop(fp, td); 684 break; 685 } 686 if (fp != fp2) { 687 flp->l_whence = SEEK_SET; 688 flp->l_start = 0; 689 flp->l_len = 0; 690 flp->l_type = F_UNLCK; 691 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 692 F_UNLCK, flp, F_POSIX); 693 } 694 fdrop(fp, td); 695 fdrop(fp2, td); 696 break; 697 698 case F_GETLK: 699 error = fget_unlocked(fdp, fd, 700 cap_rights_init(&rights, CAP_FLOCK), 0, &fp, NULL); 701 if (error != 0) 702 break; 703 if (fp->f_type != DTYPE_VNODE) { 704 error = EBADF; 705 fdrop(fp, td); 706 break; 707 } 708 flp = (struct flock *)arg; 709 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 710 flp->l_type != F_UNLCK) { 711 error = EINVAL; 712 fdrop(fp, td); 713 break; 714 } 715 if (flp->l_whence == SEEK_CUR) { 716 foffset = foffset_get(fp); 717 if ((flp->l_start > 0 && 718 foffset > OFF_MAX - flp->l_start) || 719 (flp->l_start < 0 && 720 foffset < OFF_MIN - flp->l_start)) { 721 FILEDESC_SUNLOCK(fdp); 722 error = EOVERFLOW; 723 fdrop(fp, td); 724 break; 725 } 726 flp->l_start += foffset; 727 } 728 vp = fp->f_vnode; 729 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 730 F_POSIX); 731 fdrop(fp, td); 732 break; 733 734 case F_RDAHEAD: 735 arg = arg ? 128 * 1024: 0; 736 /* FALLTHROUGH */ 737 case F_READAHEAD: 738 error = fget_unlocked(fdp, fd, NULL, 0, &fp, NULL); 739 if (error != 0) 740 break; 741 if (fp->f_type != DTYPE_VNODE) { 742 fdrop(fp, td); 743 error = EBADF; 744 break; 745 } 746 if (arg >= 0) { 747 vp = fp->f_vnode; 748 error = vn_lock(vp, LK_SHARED); 749 if (error != 0) { 750 fdrop(fp, td); 751 break; 752 } 753 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 754 VOP_UNLOCK(vp, 0); 755 fp->f_seqcount = (arg + bsize - 1) / bsize; 756 do { 757 new = old = fp->f_flag; 758 new |= FRDAHEAD; 759 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 760 } else { 761 do { 762 new = old = fp->f_flag; 763 new &= ~FRDAHEAD; 764 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 765 } 766 fdrop(fp, td); 767 break; 768 769 default: 770 error = EINVAL; 771 break; 772 } 773 return (error); 774 } 775 776 static int 777 getmaxfd(struct proc *p) 778 { 779 int maxfd; 780 781 PROC_LOCK(p); 782 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 783 PROC_UNLOCK(p); 784 785 return (maxfd); 786 } 787 788 /* 789 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 790 */ 791 int 792 do_dup(struct thread *td, int flags, int old, int new, 793 register_t *retval) 794 { 795 struct filedesc *fdp; 796 struct filedescent *oldfde, *newfde; 797 struct proc *p; 798 struct file *fp; 799 struct file *delfp; 800 int error, maxfd; 801 802 p = td->td_proc; 803 fdp = p->p_fd; 804 805 /* 806 * Verify we have a valid descriptor to dup from and possibly to 807 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 808 * return EINVAL when the new descriptor is out of bounds. 809 */ 810 if (old < 0) 811 return (EBADF); 812 if (new < 0) 813 return (flags & DUP_FCNTL ? EINVAL : EBADF); 814 maxfd = getmaxfd(p); 815 if (new >= maxfd) 816 return (flags & DUP_FCNTL ? EINVAL : EBADF); 817 818 FILEDESC_XLOCK(fdp); 819 if (fget_locked(fdp, old) == NULL) { 820 FILEDESC_XUNLOCK(fdp); 821 return (EBADF); 822 } 823 oldfde = &fdp->fd_ofiles[old]; 824 if (flags & DUP_FIXED && old == new) { 825 *retval = new; 826 if (flags & DUP_CLOEXEC) 827 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 828 FILEDESC_XUNLOCK(fdp); 829 return (0); 830 } 831 fp = oldfde->fde_file; 832 fhold(fp); 833 834 /* 835 * If the caller specified a file descriptor, make sure the file 836 * table is large enough to hold it, and grab it. Otherwise, just 837 * allocate a new descriptor the usual way. 838 */ 839 if (flags & DUP_FIXED) { 840 if (new >= fdp->fd_nfiles) { 841 /* 842 * The resource limits are here instead of e.g. 843 * fdalloc(), because the file descriptor table may be 844 * shared between processes, so we can't really use 845 * racct_add()/racct_sub(). Instead of counting the 846 * number of actually allocated descriptors, just put 847 * the limit on the size of the file descriptor table. 848 */ 849 #ifdef RACCT 850 PROC_LOCK(p); 851 error = racct_set(p, RACCT_NOFILE, new + 1); 852 PROC_UNLOCK(p); 853 if (error != 0) { 854 FILEDESC_XUNLOCK(fdp); 855 fdrop(fp, td); 856 return (EMFILE); 857 } 858 #endif 859 fdgrowtable_exp(fdp, new + 1); 860 oldfde = &fdp->fd_ofiles[old]; 861 } 862 newfde = &fdp->fd_ofiles[new]; 863 if (newfde->fde_file == NULL) 864 fdused(fdp, new); 865 } else { 866 if ((error = fdalloc(td, new, &new)) != 0) { 867 FILEDESC_XUNLOCK(fdp); 868 fdrop(fp, td); 869 return (error); 870 } 871 newfde = &fdp->fd_ofiles[new]; 872 } 873 874 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 875 KASSERT(old != new, ("new fd is same as old")); 876 877 delfp = newfde->fde_file; 878 879 /* 880 * Duplicate the source descriptor. 881 */ 882 *newfde = *oldfde; 883 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 884 if ((flags & DUP_CLOEXEC) != 0) 885 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 886 else 887 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 888 if (new > fdp->fd_lastfile) 889 fdp->fd_lastfile = new; 890 *retval = new; 891 892 if (delfp != NULL) { 893 (void) closefp(fdp, new, delfp, td, 1); 894 /* closefp() drops the FILEDESC lock for us. */ 895 } else { 896 FILEDESC_XUNLOCK(fdp); 897 } 898 899 return (0); 900 } 901 902 /* 903 * If sigio is on the list associated with a process or process group, 904 * disable signalling from the device, remove sigio from the list and 905 * free sigio. 906 */ 907 void 908 funsetown(struct sigio **sigiop) 909 { 910 struct sigio *sigio; 911 912 SIGIO_LOCK(); 913 sigio = *sigiop; 914 if (sigio == NULL) { 915 SIGIO_UNLOCK(); 916 return; 917 } 918 *(sigio->sio_myref) = NULL; 919 if ((sigio)->sio_pgid < 0) { 920 struct pgrp *pg = (sigio)->sio_pgrp; 921 PGRP_LOCK(pg); 922 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 923 sigio, sio_pgsigio); 924 PGRP_UNLOCK(pg); 925 } else { 926 struct proc *p = (sigio)->sio_proc; 927 PROC_LOCK(p); 928 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 929 sigio, sio_pgsigio); 930 PROC_UNLOCK(p); 931 } 932 SIGIO_UNLOCK(); 933 crfree(sigio->sio_ucred); 934 free(sigio, M_SIGIO); 935 } 936 937 /* 938 * Free a list of sigio structures. 939 * We only need to lock the SIGIO_LOCK because we have made ourselves 940 * inaccessible to callers of fsetown and therefore do not need to lock 941 * the proc or pgrp struct for the list manipulation. 942 */ 943 void 944 funsetownlst(struct sigiolst *sigiolst) 945 { 946 struct proc *p; 947 struct pgrp *pg; 948 struct sigio *sigio; 949 950 sigio = SLIST_FIRST(sigiolst); 951 if (sigio == NULL) 952 return; 953 p = NULL; 954 pg = NULL; 955 956 /* 957 * Every entry of the list should belong 958 * to a single proc or pgrp. 959 */ 960 if (sigio->sio_pgid < 0) { 961 pg = sigio->sio_pgrp; 962 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 963 } else /* if (sigio->sio_pgid > 0) */ { 964 p = sigio->sio_proc; 965 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 966 } 967 968 SIGIO_LOCK(); 969 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 970 *(sigio->sio_myref) = NULL; 971 if (pg != NULL) { 972 KASSERT(sigio->sio_pgid < 0, 973 ("Proc sigio in pgrp sigio list")); 974 KASSERT(sigio->sio_pgrp == pg, 975 ("Bogus pgrp in sigio list")); 976 PGRP_LOCK(pg); 977 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 978 sio_pgsigio); 979 PGRP_UNLOCK(pg); 980 } else /* if (p != NULL) */ { 981 KASSERT(sigio->sio_pgid > 0, 982 ("Pgrp sigio in proc sigio list")); 983 KASSERT(sigio->sio_proc == p, 984 ("Bogus proc in sigio list")); 985 PROC_LOCK(p); 986 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 987 sio_pgsigio); 988 PROC_UNLOCK(p); 989 } 990 SIGIO_UNLOCK(); 991 crfree(sigio->sio_ucred); 992 free(sigio, M_SIGIO); 993 SIGIO_LOCK(); 994 } 995 SIGIO_UNLOCK(); 996 } 997 998 /* 999 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1000 * 1001 * After permission checking, add a sigio structure to the sigio list for 1002 * the process or process group. 1003 */ 1004 int 1005 fsetown(pid_t pgid, struct sigio **sigiop) 1006 { 1007 struct proc *proc; 1008 struct pgrp *pgrp; 1009 struct sigio *sigio; 1010 int ret; 1011 1012 if (pgid == 0) { 1013 funsetown(sigiop); 1014 return (0); 1015 } 1016 1017 ret = 0; 1018 1019 /* Allocate and fill in the new sigio out of locks. */ 1020 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1021 sigio->sio_pgid = pgid; 1022 sigio->sio_ucred = crhold(curthread->td_ucred); 1023 sigio->sio_myref = sigiop; 1024 1025 sx_slock(&proctree_lock); 1026 if (pgid > 0) { 1027 proc = pfind(pgid); 1028 if (proc == NULL) { 1029 ret = ESRCH; 1030 goto fail; 1031 } 1032 1033 /* 1034 * Policy - Don't allow a process to FSETOWN a process 1035 * in another session. 1036 * 1037 * Remove this test to allow maximum flexibility or 1038 * restrict FSETOWN to the current process or process 1039 * group for maximum safety. 1040 */ 1041 PROC_UNLOCK(proc); 1042 if (proc->p_session != curthread->td_proc->p_session) { 1043 ret = EPERM; 1044 goto fail; 1045 } 1046 1047 pgrp = NULL; 1048 } else /* if (pgid < 0) */ { 1049 pgrp = pgfind(-pgid); 1050 if (pgrp == NULL) { 1051 ret = ESRCH; 1052 goto fail; 1053 } 1054 PGRP_UNLOCK(pgrp); 1055 1056 /* 1057 * Policy - Don't allow a process to FSETOWN a process 1058 * in another session. 1059 * 1060 * Remove this test to allow maximum flexibility or 1061 * restrict FSETOWN to the current process or process 1062 * group for maximum safety. 1063 */ 1064 if (pgrp->pg_session != curthread->td_proc->p_session) { 1065 ret = EPERM; 1066 goto fail; 1067 } 1068 1069 proc = NULL; 1070 } 1071 funsetown(sigiop); 1072 if (pgid > 0) { 1073 PROC_LOCK(proc); 1074 /* 1075 * Since funsetownlst() is called without the proctree 1076 * locked, we need to check for P_WEXIT. 1077 * XXX: is ESRCH correct? 1078 */ 1079 if ((proc->p_flag & P_WEXIT) != 0) { 1080 PROC_UNLOCK(proc); 1081 ret = ESRCH; 1082 goto fail; 1083 } 1084 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1085 sigio->sio_proc = proc; 1086 PROC_UNLOCK(proc); 1087 } else { 1088 PGRP_LOCK(pgrp); 1089 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1090 sigio->sio_pgrp = pgrp; 1091 PGRP_UNLOCK(pgrp); 1092 } 1093 sx_sunlock(&proctree_lock); 1094 SIGIO_LOCK(); 1095 *sigiop = sigio; 1096 SIGIO_UNLOCK(); 1097 return (0); 1098 1099 fail: 1100 sx_sunlock(&proctree_lock); 1101 crfree(sigio->sio_ucred); 1102 free(sigio, M_SIGIO); 1103 return (ret); 1104 } 1105 1106 /* 1107 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1108 */ 1109 pid_t 1110 fgetown(sigiop) 1111 struct sigio **sigiop; 1112 { 1113 pid_t pgid; 1114 1115 SIGIO_LOCK(); 1116 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1117 SIGIO_UNLOCK(); 1118 return (pgid); 1119 } 1120 1121 /* 1122 * Function drops the filedesc lock on return. 1123 */ 1124 static int 1125 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1126 int holdleaders) 1127 { 1128 int error; 1129 1130 FILEDESC_XLOCK_ASSERT(fdp); 1131 1132 if (holdleaders) { 1133 if (td->td_proc->p_fdtol != NULL) { 1134 /* 1135 * Ask fdfree() to sleep to ensure that all relevant 1136 * process leaders can be traversed in closef(). 1137 */ 1138 fdp->fd_holdleaderscount++; 1139 } else { 1140 holdleaders = 0; 1141 } 1142 } 1143 1144 /* 1145 * We now hold the fp reference that used to be owned by the 1146 * descriptor array. We have to unlock the FILEDESC *AFTER* 1147 * knote_fdclose to prevent a race of the fd getting opened, a knote 1148 * added, and deleteing a knote for the new fd. 1149 */ 1150 knote_fdclose(td, fd); 1151 1152 /* 1153 * We need to notify mqueue if the object is of type mqueue. 1154 */ 1155 if (fp->f_type == DTYPE_MQUEUE) 1156 mq_fdclose(td, fd, fp); 1157 FILEDESC_XUNLOCK(fdp); 1158 1159 error = closef(fp, td); 1160 if (holdleaders) { 1161 FILEDESC_XLOCK(fdp); 1162 fdp->fd_holdleaderscount--; 1163 if (fdp->fd_holdleaderscount == 0 && 1164 fdp->fd_holdleaderswakeup != 0) { 1165 fdp->fd_holdleaderswakeup = 0; 1166 wakeup(&fdp->fd_holdleaderscount); 1167 } 1168 FILEDESC_XUNLOCK(fdp); 1169 } 1170 return (error); 1171 } 1172 1173 /* 1174 * Close a file descriptor. 1175 */ 1176 #ifndef _SYS_SYSPROTO_H_ 1177 struct close_args { 1178 int fd; 1179 }; 1180 #endif 1181 /* ARGSUSED */ 1182 int 1183 sys_close(td, uap) 1184 struct thread *td; 1185 struct close_args *uap; 1186 { 1187 1188 return (kern_close(td, uap->fd)); 1189 } 1190 1191 int 1192 kern_close(td, fd) 1193 struct thread *td; 1194 int fd; 1195 { 1196 struct filedesc *fdp; 1197 struct file *fp; 1198 1199 fdp = td->td_proc->p_fd; 1200 1201 AUDIT_SYSCLOSE(td, fd); 1202 1203 FILEDESC_XLOCK(fdp); 1204 if ((fp = fget_locked(fdp, fd)) == NULL) { 1205 FILEDESC_XUNLOCK(fdp); 1206 return (EBADF); 1207 } 1208 fdfree(fdp, fd); 1209 1210 /* closefp() drops the FILEDESC lock for us. */ 1211 return (closefp(fdp, fd, fp, td, 1)); 1212 } 1213 1214 /* 1215 * Close open file descriptors. 1216 */ 1217 #ifndef _SYS_SYSPROTO_H_ 1218 struct closefrom_args { 1219 int lowfd; 1220 }; 1221 #endif 1222 /* ARGSUSED */ 1223 int 1224 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1225 { 1226 struct filedesc *fdp; 1227 int fd; 1228 1229 fdp = td->td_proc->p_fd; 1230 AUDIT_ARG_FD(uap->lowfd); 1231 1232 /* 1233 * Treat negative starting file descriptor values identical to 1234 * closefrom(0) which closes all files. 1235 */ 1236 if (uap->lowfd < 0) 1237 uap->lowfd = 0; 1238 FILEDESC_SLOCK(fdp); 1239 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) { 1240 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1241 FILEDESC_SUNLOCK(fdp); 1242 (void)kern_close(td, fd); 1243 FILEDESC_SLOCK(fdp); 1244 } 1245 } 1246 FILEDESC_SUNLOCK(fdp); 1247 return (0); 1248 } 1249 1250 #if defined(COMPAT_43) 1251 /* 1252 * Return status information about a file descriptor. 1253 */ 1254 #ifndef _SYS_SYSPROTO_H_ 1255 struct ofstat_args { 1256 int fd; 1257 struct ostat *sb; 1258 }; 1259 #endif 1260 /* ARGSUSED */ 1261 int 1262 ofstat(struct thread *td, struct ofstat_args *uap) 1263 { 1264 struct ostat oub; 1265 struct stat ub; 1266 int error; 1267 1268 error = kern_fstat(td, uap->fd, &ub); 1269 if (error == 0) { 1270 cvtstat(&ub, &oub); 1271 error = copyout(&oub, uap->sb, sizeof(oub)); 1272 } 1273 return (error); 1274 } 1275 #endif /* COMPAT_43 */ 1276 1277 /* 1278 * Return status information about a file descriptor. 1279 */ 1280 #ifndef _SYS_SYSPROTO_H_ 1281 struct fstat_args { 1282 int fd; 1283 struct stat *sb; 1284 }; 1285 #endif 1286 /* ARGSUSED */ 1287 int 1288 sys_fstat(struct thread *td, struct fstat_args *uap) 1289 { 1290 struct stat ub; 1291 int error; 1292 1293 error = kern_fstat(td, uap->fd, &ub); 1294 if (error == 0) 1295 error = copyout(&ub, uap->sb, sizeof(ub)); 1296 return (error); 1297 } 1298 1299 int 1300 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1301 { 1302 struct file *fp; 1303 cap_rights_t rights; 1304 int error; 1305 1306 AUDIT_ARG_FD(fd); 1307 1308 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1309 if (error != 0) 1310 return (error); 1311 1312 AUDIT_ARG_FILE(td->td_proc, fp); 1313 1314 error = fo_stat(fp, sbp, td->td_ucred, td); 1315 fdrop(fp, td); 1316 #ifdef KTRACE 1317 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1318 ktrstat(sbp); 1319 #endif 1320 return (error); 1321 } 1322 1323 /* 1324 * Return status information about a file descriptor. 1325 */ 1326 #ifndef _SYS_SYSPROTO_H_ 1327 struct nfstat_args { 1328 int fd; 1329 struct nstat *sb; 1330 }; 1331 #endif 1332 /* ARGSUSED */ 1333 int 1334 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1335 { 1336 struct nstat nub; 1337 struct stat ub; 1338 int error; 1339 1340 error = kern_fstat(td, uap->fd, &ub); 1341 if (error == 0) { 1342 cvtnstat(&ub, &nub); 1343 error = copyout(&nub, uap->sb, sizeof(nub)); 1344 } 1345 return (error); 1346 } 1347 1348 /* 1349 * Return pathconf information about a file descriptor. 1350 */ 1351 #ifndef _SYS_SYSPROTO_H_ 1352 struct fpathconf_args { 1353 int fd; 1354 int name; 1355 }; 1356 #endif 1357 /* ARGSUSED */ 1358 int 1359 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1360 { 1361 struct file *fp; 1362 struct vnode *vp; 1363 cap_rights_t rights; 1364 int error; 1365 1366 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1367 if (error != 0) 1368 return (error); 1369 1370 /* If asynchronous I/O is available, it works for all descriptors. */ 1371 if (uap->name == _PC_ASYNC_IO) { 1372 td->td_retval[0] = async_io_version; 1373 goto out; 1374 } 1375 vp = fp->f_vnode; 1376 if (vp != NULL) { 1377 vn_lock(vp, LK_SHARED | LK_RETRY); 1378 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1379 VOP_UNLOCK(vp, 0); 1380 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1381 if (uap->name != _PC_PIPE_BUF) { 1382 error = EINVAL; 1383 } else { 1384 td->td_retval[0] = PIPE_BUF; 1385 error = 0; 1386 } 1387 } else { 1388 error = EOPNOTSUPP; 1389 } 1390 out: 1391 fdrop(fp, td); 1392 return (error); 1393 } 1394 1395 /* 1396 * Initialize filecaps structure. 1397 */ 1398 void 1399 filecaps_init(struct filecaps *fcaps) 1400 { 1401 1402 bzero(fcaps, sizeof(*fcaps)); 1403 fcaps->fc_nioctls = -1; 1404 } 1405 1406 /* 1407 * Copy filecaps structure allocating memory for ioctls array if needed. 1408 */ 1409 void 1410 filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1411 { 1412 size_t size; 1413 1414 *dst = *src; 1415 if (src->fc_ioctls != NULL) { 1416 KASSERT(src->fc_nioctls > 0, 1417 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1418 1419 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1420 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1421 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1422 } 1423 } 1424 1425 /* 1426 * Move filecaps structure to the new place and clear the old place. 1427 */ 1428 void 1429 filecaps_move(struct filecaps *src, struct filecaps *dst) 1430 { 1431 1432 *dst = *src; 1433 bzero(src, sizeof(*src)); 1434 } 1435 1436 /* 1437 * Fill the given filecaps structure with full rights. 1438 */ 1439 static void 1440 filecaps_fill(struct filecaps *fcaps) 1441 { 1442 1443 CAP_ALL(&fcaps->fc_rights); 1444 fcaps->fc_ioctls = NULL; 1445 fcaps->fc_nioctls = -1; 1446 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1447 } 1448 1449 /* 1450 * Free memory allocated within filecaps structure. 1451 */ 1452 void 1453 filecaps_free(struct filecaps *fcaps) 1454 { 1455 1456 free(fcaps->fc_ioctls, M_FILECAPS); 1457 bzero(fcaps, sizeof(*fcaps)); 1458 } 1459 1460 /* 1461 * Validate the given filecaps structure. 1462 */ 1463 static void 1464 filecaps_validate(const struct filecaps *fcaps, const char *func) 1465 { 1466 1467 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1468 ("%s: invalid rights", func)); 1469 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1470 ("%s: invalid fcntls", func)); 1471 KASSERT(fcaps->fc_fcntls == 0 || 1472 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1473 ("%s: fcntls without CAP_FCNTL", func)); 1474 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1475 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1476 ("%s: invalid ioctls", func)); 1477 KASSERT(fcaps->fc_nioctls == 0 || 1478 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1479 ("%s: ioctls without CAP_IOCTL", func)); 1480 } 1481 1482 static void 1483 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1484 { 1485 int nfd1, maxfd; 1486 1487 FILEDESC_XLOCK_ASSERT(fdp); 1488 1489 nfd1 = fdp->fd_nfiles * 2; 1490 if (nfd1 < nfd) 1491 nfd1 = nfd; 1492 maxfd = getmaxfd(curproc); 1493 if (maxfd < nfd1) 1494 nfd1 = maxfd; 1495 KASSERT(nfd <= nfd1, 1496 ("too low nfd1 %d %d %d %d", nfd, fdp->fd_nfiles, maxfd, nfd1)); 1497 fdgrowtable(fdp, nfd1); 1498 } 1499 1500 /* 1501 * Grow the file table to accomodate (at least) nfd descriptors. 1502 */ 1503 static void 1504 fdgrowtable(struct filedesc *fdp, int nfd) 1505 { 1506 struct filedesc0 *fdp0; 1507 struct freetable *ft; 1508 struct filedescent *ntable; 1509 struct filedescent *otable; 1510 int nnfiles, onfiles; 1511 NDSLOTTYPE *nmap, *omap; 1512 1513 FILEDESC_XLOCK_ASSERT(fdp); 1514 1515 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1516 1517 /* save old values */ 1518 onfiles = fdp->fd_nfiles; 1519 otable = fdp->fd_ofiles; 1520 omap = fdp->fd_map; 1521 1522 /* compute the size of the new table */ 1523 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1524 if (nnfiles <= onfiles) 1525 /* the table is already large enough */ 1526 return; 1527 1528 /* 1529 * Allocate a new table and map. We need enough space for the 1530 * file entries themselves and the struct freetable we will use 1531 * when we decommission the table and place it on the freelist. 1532 * We place the struct freetable in the middle so we don't have 1533 * to worry about padding. 1534 */ 1535 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1536 M_FILEDESC, M_ZERO | M_WAITOK); 1537 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1538 M_ZERO | M_WAITOK); 1539 1540 /* copy the old data over and point at the new tables */ 1541 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1542 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1543 1544 /* update the pointers and counters */ 1545 memcpy(ntable, otable, onfiles * sizeof(ntable[0])); 1546 fdp->fd_ofiles = ntable; 1547 fdp->fd_map = nmap; 1548 1549 /* 1550 * In order to have a valid pattern for fget_unlocked() 1551 * fdp->fd_nfiles must be the last member to be updated, otherwise 1552 * fget_unlocked() consumers may reference a new, higher value for 1553 * fdp->fd_nfiles before to access the fdp->fd_ofiles array, 1554 * resulting in OOB accesses. 1555 */ 1556 atomic_store_rel_int(&fdp->fd_nfiles, nnfiles); 1557 1558 /* 1559 * Do not free the old file table, as some threads may still 1560 * reference entries within it. Instead, place it on a freelist 1561 * which will be processed when the struct filedesc is released. 1562 * 1563 * Do, however, free the old map. 1564 * 1565 * Note that if onfiles == NDFILE, we're dealing with the original 1566 * static allocation contained within (struct filedesc0 *)fdp, 1567 * which must not be freed. 1568 */ 1569 if (onfiles > NDFILE) { 1570 ft = (struct freetable *)&otable[onfiles]; 1571 fdp0 = (struct filedesc0 *)fdp; 1572 ft->ft_table = otable; 1573 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1574 free(omap, M_FILEDESC); 1575 } 1576 } 1577 1578 /* 1579 * Allocate a file descriptor for the process. 1580 */ 1581 int 1582 fdalloc(struct thread *td, int minfd, int *result) 1583 { 1584 struct proc *p = td->td_proc; 1585 struct filedesc *fdp = p->p_fd; 1586 int fd = -1, maxfd, allocfd; 1587 #ifdef RACCT 1588 int error; 1589 #endif 1590 1591 FILEDESC_XLOCK_ASSERT(fdp); 1592 1593 if (fdp->fd_freefile > minfd) 1594 minfd = fdp->fd_freefile; 1595 1596 maxfd = getmaxfd(p); 1597 1598 /* 1599 * Search the bitmap for a free descriptor starting at minfd. 1600 * If none is found, grow the file table. 1601 */ 1602 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1603 if (fd >= maxfd) 1604 return (EMFILE); 1605 if (fd >= fdp->fd_nfiles) { 1606 allocfd = min(fd * 2, maxfd); 1607 #ifdef RACCT 1608 PROC_LOCK(p); 1609 error = racct_set(p, RACCT_NOFILE, allocfd); 1610 PROC_UNLOCK(p); 1611 if (error != 0) 1612 return (EMFILE); 1613 #endif 1614 /* 1615 * fd is already equal to first free descriptor >= minfd, so 1616 * we only need to grow the table and we are done. 1617 */ 1618 fdgrowtable_exp(fdp, allocfd); 1619 } 1620 1621 /* 1622 * Perform some sanity checks, then mark the file descriptor as 1623 * used and return it to the caller. 1624 */ 1625 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1626 ("invalid descriptor %d", fd)); 1627 KASSERT(!fdisused(fdp, fd), 1628 ("fd_first_free() returned non-free descriptor")); 1629 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1630 ("file descriptor isn't free")); 1631 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1632 fdused(fdp, fd); 1633 *result = fd; 1634 return (0); 1635 } 1636 1637 /* 1638 * Allocate n file descriptors for the process. 1639 */ 1640 int 1641 fdallocn(struct thread *td, int minfd, int *fds, int n) 1642 { 1643 struct proc *p = td->td_proc; 1644 struct filedesc *fdp = p->p_fd; 1645 int i; 1646 1647 FILEDESC_XLOCK_ASSERT(fdp); 1648 1649 if (!fdavail(td, n)) 1650 return (EMFILE); 1651 1652 for (i = 0; i < n; i++) 1653 if (fdalloc(td, 0, &fds[i]) != 0) 1654 break; 1655 1656 if (i < n) { 1657 for (i--; i >= 0; i--) 1658 fdunused(fdp, fds[i]); 1659 return (EMFILE); 1660 } 1661 1662 return (0); 1663 } 1664 1665 /* 1666 * Check to see whether n user file descriptors are available to the process 1667 * p. 1668 */ 1669 int 1670 fdavail(struct thread *td, int n) 1671 { 1672 struct proc *p = td->td_proc; 1673 struct filedesc *fdp = td->td_proc->p_fd; 1674 int i, lim, last; 1675 1676 FILEDESC_LOCK_ASSERT(fdp); 1677 1678 /* 1679 * XXX: This is only called from uipc_usrreq.c:unp_externalize(); 1680 * call racct_add() from there instead of dealing with containers 1681 * here. 1682 */ 1683 lim = getmaxfd(p); 1684 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) 1685 return (1); 1686 last = min(fdp->fd_nfiles, lim); 1687 for (i = fdp->fd_freefile; i < last; i++) { 1688 if (fdp->fd_ofiles[i].fde_file == NULL && --n <= 0) 1689 return (1); 1690 } 1691 return (0); 1692 } 1693 1694 /* 1695 * Create a new open file structure and allocate a file decriptor for the 1696 * process that refers to it. We add one reference to the file for the 1697 * descriptor table and one reference for resultfp. This is to prevent us 1698 * being preempted and the entry in the descriptor table closed after we 1699 * release the FILEDESC lock. 1700 */ 1701 int 1702 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1703 { 1704 struct file *fp; 1705 int error, fd; 1706 1707 error = falloc_noinstall(td, &fp); 1708 if (error) 1709 return (error); /* no reference held on error */ 1710 1711 error = finstall(td, fp, &fd, flags, NULL); 1712 if (error) { 1713 fdrop(fp, td); /* one reference (fp only) */ 1714 return (error); 1715 } 1716 1717 if (resultfp != NULL) 1718 *resultfp = fp; /* copy out result */ 1719 else 1720 fdrop(fp, td); /* release local reference */ 1721 1722 if (resultfd != NULL) 1723 *resultfd = fd; 1724 1725 return (0); 1726 } 1727 1728 /* 1729 * Create a new open file structure without allocating a file descriptor. 1730 */ 1731 int 1732 falloc_noinstall(struct thread *td, struct file **resultfp) 1733 { 1734 struct file *fp; 1735 int maxuserfiles = maxfiles - (maxfiles / 20); 1736 static struct timeval lastfail; 1737 static int curfail; 1738 1739 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1740 1741 if ((openfiles >= maxuserfiles && 1742 priv_check(td, PRIV_MAXFILES) != 0) || 1743 openfiles >= maxfiles) { 1744 if (ppsratecheck(&lastfail, &curfail, 1)) { 1745 printf("kern.maxfiles limit exceeded by uid %i, " 1746 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1747 } 1748 return (ENFILE); 1749 } 1750 atomic_add_int(&openfiles, 1); 1751 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1752 refcount_init(&fp->f_count, 1); 1753 fp->f_cred = crhold(td->td_ucred); 1754 fp->f_ops = &badfileops; 1755 fp->f_data = NULL; 1756 fp->f_vnode = NULL; 1757 *resultfp = fp; 1758 return (0); 1759 } 1760 1761 /* 1762 * Install a file in a file descriptor table. 1763 */ 1764 int 1765 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1766 struct filecaps *fcaps) 1767 { 1768 struct filedesc *fdp = td->td_proc->p_fd; 1769 struct filedescent *fde; 1770 int error; 1771 1772 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1773 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1774 if (fcaps != NULL) 1775 filecaps_validate(fcaps, __func__); 1776 1777 FILEDESC_XLOCK(fdp); 1778 if ((error = fdalloc(td, 0, fd))) { 1779 FILEDESC_XUNLOCK(fdp); 1780 return (error); 1781 } 1782 fhold(fp); 1783 fde = &fdp->fd_ofiles[*fd]; 1784 fde->fde_file = fp; 1785 if ((flags & O_CLOEXEC) != 0) 1786 fde->fde_flags |= UF_EXCLOSE; 1787 if (fcaps != NULL) 1788 filecaps_move(fcaps, &fde->fde_caps); 1789 else 1790 filecaps_fill(&fde->fde_caps); 1791 FILEDESC_XUNLOCK(fdp); 1792 return (0); 1793 } 1794 1795 /* 1796 * Build a new filedesc structure from another. 1797 * Copy the current, root, and jail root vnode references. 1798 */ 1799 struct filedesc * 1800 fdinit(struct filedesc *fdp) 1801 { 1802 struct filedesc0 *newfdp; 1803 1804 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1805 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1806 if (fdp != NULL) { 1807 FILEDESC_XLOCK(fdp); 1808 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1809 if (newfdp->fd_fd.fd_cdir) 1810 VREF(newfdp->fd_fd.fd_cdir); 1811 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1812 if (newfdp->fd_fd.fd_rdir) 1813 VREF(newfdp->fd_fd.fd_rdir); 1814 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1815 if (newfdp->fd_fd.fd_jdir) 1816 VREF(newfdp->fd_fd.fd_jdir); 1817 FILEDESC_XUNLOCK(fdp); 1818 } 1819 1820 /* Create the file descriptor table. */ 1821 newfdp->fd_fd.fd_refcnt = 1; 1822 newfdp->fd_fd.fd_holdcnt = 1; 1823 newfdp->fd_fd.fd_cmask = CMASK; 1824 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1825 newfdp->fd_fd.fd_nfiles = NDFILE; 1826 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1827 newfdp->fd_fd.fd_lastfile = -1; 1828 return (&newfdp->fd_fd); 1829 } 1830 1831 static struct filedesc * 1832 fdhold(struct proc *p) 1833 { 1834 struct filedesc *fdp; 1835 1836 mtx_lock(&fdesc_mtx); 1837 fdp = p->p_fd; 1838 if (fdp != NULL) 1839 fdp->fd_holdcnt++; 1840 mtx_unlock(&fdesc_mtx); 1841 return (fdp); 1842 } 1843 1844 static void 1845 fddrop(struct filedesc *fdp) 1846 { 1847 struct filedesc0 *fdp0; 1848 struct freetable *ft; 1849 int i; 1850 1851 mtx_lock(&fdesc_mtx); 1852 i = --fdp->fd_holdcnt; 1853 mtx_unlock(&fdesc_mtx); 1854 if (i > 0) 1855 return; 1856 1857 FILEDESC_LOCK_DESTROY(fdp); 1858 fdp0 = (struct filedesc0 *)fdp; 1859 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1860 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1861 free(ft->ft_table, M_FILEDESC); 1862 } 1863 free(fdp, M_FILEDESC); 1864 } 1865 1866 /* 1867 * Share a filedesc structure. 1868 */ 1869 struct filedesc * 1870 fdshare(struct filedesc *fdp) 1871 { 1872 1873 FILEDESC_XLOCK(fdp); 1874 fdp->fd_refcnt++; 1875 FILEDESC_XUNLOCK(fdp); 1876 return (fdp); 1877 } 1878 1879 /* 1880 * Unshare a filedesc structure, if necessary by making a copy 1881 */ 1882 void 1883 fdunshare(struct proc *p, struct thread *td) 1884 { 1885 1886 FILEDESC_XLOCK(p->p_fd); 1887 if (p->p_fd->fd_refcnt > 1) { 1888 struct filedesc *tmp; 1889 1890 FILEDESC_XUNLOCK(p->p_fd); 1891 tmp = fdcopy(p->p_fd); 1892 fdescfree(td); 1893 p->p_fd = tmp; 1894 } else 1895 FILEDESC_XUNLOCK(p->p_fd); 1896 } 1897 1898 /* 1899 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1900 * this is to ease callers, not catch errors. 1901 */ 1902 struct filedesc * 1903 fdcopy(struct filedesc *fdp) 1904 { 1905 struct filedesc *newfdp; 1906 struct filedescent *nfde, *ofde; 1907 int i; 1908 1909 /* Certain daemons might not have file descriptors. */ 1910 if (fdp == NULL) 1911 return (NULL); 1912 1913 newfdp = fdinit(fdp); 1914 FILEDESC_SLOCK(fdp); 1915 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1916 FILEDESC_SUNLOCK(fdp); 1917 FILEDESC_XLOCK(newfdp); 1918 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1919 FILEDESC_XUNLOCK(newfdp); 1920 FILEDESC_SLOCK(fdp); 1921 } 1922 /* copy all passable descriptors (i.e. not kqueue) */ 1923 newfdp->fd_freefile = -1; 1924 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1925 ofde = &fdp->fd_ofiles[i]; 1926 if (fdisused(fdp, i) && 1927 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1928 ofde->fde_file->f_ops != &badfileops) { 1929 nfde = &newfdp->fd_ofiles[i]; 1930 *nfde = *ofde; 1931 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1932 fhold(nfde->fde_file); 1933 newfdp->fd_lastfile = i; 1934 } else { 1935 if (newfdp->fd_freefile == -1) 1936 newfdp->fd_freefile = i; 1937 } 1938 } 1939 newfdp->fd_cmask = fdp->fd_cmask; 1940 FILEDESC_SUNLOCK(fdp); 1941 FILEDESC_XLOCK(newfdp); 1942 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1943 if (newfdp->fd_ofiles[i].fde_file != NULL) 1944 fdused(newfdp, i); 1945 } 1946 if (newfdp->fd_freefile == -1) 1947 newfdp->fd_freefile = i; 1948 FILEDESC_XUNLOCK(newfdp); 1949 return (newfdp); 1950 } 1951 1952 /* 1953 * Release a filedesc structure. 1954 */ 1955 void 1956 fdescfree(struct thread *td) 1957 { 1958 struct filedesc *fdp; 1959 int i; 1960 struct filedesc_to_leader *fdtol; 1961 struct file *fp; 1962 struct vnode *cdir, *jdir, *rdir, *vp; 1963 struct flock lf; 1964 1965 /* Certain daemons might not have file descriptors. */ 1966 fdp = td->td_proc->p_fd; 1967 if (fdp == NULL) 1968 return; 1969 1970 #ifdef RACCT 1971 PROC_LOCK(td->td_proc); 1972 racct_set(td->td_proc, RACCT_NOFILE, 0); 1973 PROC_UNLOCK(td->td_proc); 1974 #endif 1975 1976 /* Check for special need to clear POSIX style locks */ 1977 fdtol = td->td_proc->p_fdtol; 1978 if (fdtol != NULL) { 1979 FILEDESC_XLOCK(fdp); 1980 KASSERT(fdtol->fdl_refcount > 0, 1981 ("filedesc_to_refcount botch: fdl_refcount=%d", 1982 fdtol->fdl_refcount)); 1983 if (fdtol->fdl_refcount == 1 && 1984 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1985 for (i = 0; i <= fdp->fd_lastfile; i++) { 1986 fp = fdp->fd_ofiles[i].fde_file; 1987 if (fp == NULL || fp->f_type != DTYPE_VNODE) 1988 continue; 1989 fhold(fp); 1990 FILEDESC_XUNLOCK(fdp); 1991 lf.l_whence = SEEK_SET; 1992 lf.l_start = 0; 1993 lf.l_len = 0; 1994 lf.l_type = F_UNLCK; 1995 vp = fp->f_vnode; 1996 (void) VOP_ADVLOCK(vp, 1997 (caddr_t)td->td_proc->p_leader, F_UNLCK, 1998 &lf, F_POSIX); 1999 FILEDESC_XLOCK(fdp); 2000 fdrop(fp, td); 2001 } 2002 } 2003 retry: 2004 if (fdtol->fdl_refcount == 1) { 2005 if (fdp->fd_holdleaderscount > 0 && 2006 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2007 /* 2008 * close() or do_dup() has cleared a reference 2009 * in a shared file descriptor table. 2010 */ 2011 fdp->fd_holdleaderswakeup = 1; 2012 sx_sleep(&fdp->fd_holdleaderscount, 2013 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2014 goto retry; 2015 } 2016 if (fdtol->fdl_holdcount > 0) { 2017 /* 2018 * Ensure that fdtol->fdl_leader remains 2019 * valid in closef(). 2020 */ 2021 fdtol->fdl_wakeup = 1; 2022 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2023 "fdlhold", 0); 2024 goto retry; 2025 } 2026 } 2027 fdtol->fdl_refcount--; 2028 if (fdtol->fdl_refcount == 0 && 2029 fdtol->fdl_holdcount == 0) { 2030 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2031 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2032 } else 2033 fdtol = NULL; 2034 td->td_proc->p_fdtol = NULL; 2035 FILEDESC_XUNLOCK(fdp); 2036 if (fdtol != NULL) 2037 free(fdtol, M_FILEDESC_TO_LEADER); 2038 } 2039 FILEDESC_XLOCK(fdp); 2040 i = --fdp->fd_refcnt; 2041 FILEDESC_XUNLOCK(fdp); 2042 if (i > 0) 2043 return; 2044 2045 for (i = 0; i <= fdp->fd_lastfile; i++) { 2046 fp = fdp->fd_ofiles[i].fde_file; 2047 if (fp != NULL) { 2048 FILEDESC_XLOCK(fdp); 2049 fdfree(fdp, i); 2050 FILEDESC_XUNLOCK(fdp); 2051 (void) closef(fp, td); 2052 } 2053 } 2054 FILEDESC_XLOCK(fdp); 2055 2056 /* XXX This should happen earlier. */ 2057 mtx_lock(&fdesc_mtx); 2058 td->td_proc->p_fd = NULL; 2059 mtx_unlock(&fdesc_mtx); 2060 2061 if (fdp->fd_nfiles > NDFILE) 2062 free(fdp->fd_ofiles, M_FILEDESC); 2063 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2064 free(fdp->fd_map, M_FILEDESC); 2065 2066 fdp->fd_nfiles = 0; 2067 2068 cdir = fdp->fd_cdir; 2069 fdp->fd_cdir = NULL; 2070 rdir = fdp->fd_rdir; 2071 fdp->fd_rdir = NULL; 2072 jdir = fdp->fd_jdir; 2073 fdp->fd_jdir = NULL; 2074 FILEDESC_XUNLOCK(fdp); 2075 2076 if (cdir != NULL) 2077 vrele(cdir); 2078 if (rdir != NULL) 2079 vrele(rdir); 2080 if (jdir != NULL) 2081 vrele(jdir); 2082 2083 fddrop(fdp); 2084 } 2085 2086 /* 2087 * For setugid programs, we don't want to people to use that setugidness 2088 * to generate error messages which write to a file which otherwise would 2089 * otherwise be off-limits to the process. We check for filesystems where 2090 * the vnode can change out from under us after execve (like [lin]procfs). 2091 * 2092 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2093 * sufficient. We also don't check for setugidness since we know we are. 2094 */ 2095 static int 2096 is_unsafe(struct file *fp) 2097 { 2098 if (fp->f_type == DTYPE_VNODE) { 2099 struct vnode *vp = fp->f_vnode; 2100 2101 if ((vp->v_vflag & VV_PROCDEP) != 0) 2102 return (1); 2103 } 2104 return (0); 2105 } 2106 2107 /* 2108 * Make this setguid thing safe, if at all possible. 2109 */ 2110 void 2111 setugidsafety(struct thread *td) 2112 { 2113 struct filedesc *fdp; 2114 struct file *fp; 2115 int i; 2116 2117 /* Certain daemons might not have file descriptors. */ 2118 fdp = td->td_proc->p_fd; 2119 if (fdp == NULL) 2120 return; 2121 2122 /* 2123 * Note: fdp->fd_ofiles may be reallocated out from under us while 2124 * we are blocked in a close. Be careful! 2125 */ 2126 FILEDESC_XLOCK(fdp); 2127 for (i = 0; i <= fdp->fd_lastfile; i++) { 2128 if (i > 2) 2129 break; 2130 fp = fdp->fd_ofiles[i].fde_file; 2131 if (fp != NULL && is_unsafe(fp)) { 2132 knote_fdclose(td, i); 2133 /* 2134 * NULL-out descriptor prior to close to avoid 2135 * a race while close blocks. 2136 */ 2137 fdfree(fdp, i); 2138 FILEDESC_XUNLOCK(fdp); 2139 (void) closef(fp, td); 2140 FILEDESC_XLOCK(fdp); 2141 } 2142 } 2143 FILEDESC_XUNLOCK(fdp); 2144 } 2145 2146 /* 2147 * If a specific file object occupies a specific file descriptor, close the 2148 * file descriptor entry and drop a reference on the file object. This is a 2149 * convenience function to handle a subsequent error in a function that calls 2150 * falloc() that handles the race that another thread might have closed the 2151 * file descriptor out from under the thread creating the file object. 2152 */ 2153 void 2154 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2155 { 2156 2157 FILEDESC_XLOCK(fdp); 2158 if (fdp->fd_ofiles[idx].fde_file == fp) { 2159 fdfree(fdp, idx); 2160 FILEDESC_XUNLOCK(fdp); 2161 fdrop(fp, td); 2162 } else 2163 FILEDESC_XUNLOCK(fdp); 2164 } 2165 2166 /* 2167 * Close any files on exec? 2168 */ 2169 void 2170 fdcloseexec(struct thread *td) 2171 { 2172 struct filedesc *fdp; 2173 struct filedescent *fde; 2174 struct file *fp; 2175 int i; 2176 2177 /* Certain daemons might not have file descriptors. */ 2178 fdp = td->td_proc->p_fd; 2179 if (fdp == NULL) 2180 return; 2181 2182 /* 2183 * We cannot cache fd_ofiles since operations 2184 * may block and rip them out from under us. 2185 */ 2186 FILEDESC_XLOCK(fdp); 2187 for (i = 0; i <= fdp->fd_lastfile; i++) { 2188 fde = &fdp->fd_ofiles[i]; 2189 fp = fde->fde_file; 2190 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2191 (fde->fde_flags & UF_EXCLOSE))) { 2192 fdfree(fdp, i); 2193 (void) closefp(fdp, i, fp, td, 0); 2194 /* closefp() drops the FILEDESC lock. */ 2195 FILEDESC_XLOCK(fdp); 2196 } 2197 } 2198 FILEDESC_XUNLOCK(fdp); 2199 } 2200 2201 /* 2202 * It is unsafe for set[ug]id processes to be started with file 2203 * descriptors 0..2 closed, as these descriptors are given implicit 2204 * significance in the Standard C library. fdcheckstd() will create a 2205 * descriptor referencing /dev/null for each of stdin, stdout, and 2206 * stderr that is not already open. 2207 */ 2208 int 2209 fdcheckstd(struct thread *td) 2210 { 2211 struct filedesc *fdp; 2212 register_t retval, save; 2213 int i, error, devnull; 2214 2215 fdp = td->td_proc->p_fd; 2216 if (fdp == NULL) 2217 return (0); 2218 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2219 devnull = -1; 2220 error = 0; 2221 for (i = 0; i < 3; i++) { 2222 if (fdp->fd_ofiles[i].fde_file != NULL) 2223 continue; 2224 if (devnull < 0) { 2225 save = td->td_retval[0]; 2226 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2227 O_RDWR, 0); 2228 devnull = td->td_retval[0]; 2229 td->td_retval[0] = save; 2230 if (error) 2231 break; 2232 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2233 } else { 2234 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2235 if (error != 0) 2236 break; 2237 } 2238 } 2239 return (error); 2240 } 2241 2242 /* 2243 * Internal form of close. Decrement reference count on file structure. 2244 * Note: td may be NULL when closing a file that was being passed in a 2245 * message. 2246 * 2247 * XXXRW: Giant is not required for the caller, but often will be held; this 2248 * makes it moderately likely the Giant will be recursed in the VFS case. 2249 */ 2250 int 2251 closef(struct file *fp, struct thread *td) 2252 { 2253 struct vnode *vp; 2254 struct flock lf; 2255 struct filedesc_to_leader *fdtol; 2256 struct filedesc *fdp; 2257 2258 /* 2259 * POSIX record locking dictates that any close releases ALL 2260 * locks owned by this process. This is handled by setting 2261 * a flag in the unlock to free ONLY locks obeying POSIX 2262 * semantics, and not to free BSD-style file locks. 2263 * If the descriptor was in a message, POSIX-style locks 2264 * aren't passed with the descriptor, and the thread pointer 2265 * will be NULL. Callers should be careful only to pass a 2266 * NULL thread pointer when there really is no owning 2267 * context that might have locks, or the locks will be 2268 * leaked. 2269 */ 2270 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2271 vp = fp->f_vnode; 2272 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2273 lf.l_whence = SEEK_SET; 2274 lf.l_start = 0; 2275 lf.l_len = 0; 2276 lf.l_type = F_UNLCK; 2277 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2278 F_UNLCK, &lf, F_POSIX); 2279 } 2280 fdtol = td->td_proc->p_fdtol; 2281 if (fdtol != NULL) { 2282 /* 2283 * Handle special case where file descriptor table is 2284 * shared between multiple process leaders. 2285 */ 2286 fdp = td->td_proc->p_fd; 2287 FILEDESC_XLOCK(fdp); 2288 for (fdtol = fdtol->fdl_next; 2289 fdtol != td->td_proc->p_fdtol; 2290 fdtol = fdtol->fdl_next) { 2291 if ((fdtol->fdl_leader->p_flag & 2292 P_ADVLOCK) == 0) 2293 continue; 2294 fdtol->fdl_holdcount++; 2295 FILEDESC_XUNLOCK(fdp); 2296 lf.l_whence = SEEK_SET; 2297 lf.l_start = 0; 2298 lf.l_len = 0; 2299 lf.l_type = F_UNLCK; 2300 vp = fp->f_vnode; 2301 (void) VOP_ADVLOCK(vp, 2302 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2303 F_POSIX); 2304 FILEDESC_XLOCK(fdp); 2305 fdtol->fdl_holdcount--; 2306 if (fdtol->fdl_holdcount == 0 && 2307 fdtol->fdl_wakeup != 0) { 2308 fdtol->fdl_wakeup = 0; 2309 wakeup(fdtol); 2310 } 2311 } 2312 FILEDESC_XUNLOCK(fdp); 2313 } 2314 } 2315 return (fdrop(fp, td)); 2316 } 2317 2318 /* 2319 * Initialize the file pointer with the specified properties. 2320 * 2321 * The ops are set with release semantics to be certain that the flags, type, 2322 * and data are visible when ops is. This is to prevent ops methods from being 2323 * called with bad data. 2324 */ 2325 void 2326 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2327 { 2328 fp->f_data = data; 2329 fp->f_flag = flag; 2330 fp->f_type = type; 2331 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2332 } 2333 2334 int 2335 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2336 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2337 { 2338 struct file *fp; 2339 u_int count; 2340 #ifdef CAPABILITIES 2341 cap_rights_t haverights; 2342 int error; 2343 #endif 2344 2345 /* 2346 * Avoid reads reordering and then a first access to the 2347 * fdp->fd_ofiles table which could result in OOB operation. 2348 */ 2349 if (fd < 0 || fd >= atomic_load_acq_int(&fdp->fd_nfiles)) 2350 return (EBADF); 2351 /* 2352 * Fetch the descriptor locklessly. We avoid fdrop() races by 2353 * never raising a refcount above 0. To accomplish this we have 2354 * to use a cmpset loop rather than an atomic_add. The descriptor 2355 * must be re-verified once we acquire a reference to be certain 2356 * that the identity is still correct and we did not lose a race 2357 * due to preemption. 2358 */ 2359 for (;;) { 2360 fp = fdp->fd_ofiles[fd].fde_file; 2361 if (fp == NULL) 2362 return (EBADF); 2363 #ifdef CAPABILITIES 2364 haverights = *cap_rights(fdp, fd); 2365 if (needrightsp != NULL) { 2366 error = cap_check(&haverights, needrightsp); 2367 if (error != 0) 2368 return (error); 2369 if (cap_rights_is_set(needrightsp, CAP_FCNTL)) { 2370 error = cap_fcntl_check(fdp, fd, needfcntl); 2371 if (error != 0) 2372 return (error); 2373 } 2374 } 2375 #endif 2376 count = fp->f_count; 2377 if (count == 0) 2378 continue; 2379 /* 2380 * Use an acquire barrier to prevent caching of fd_ofiles 2381 * so it is refreshed for verification. 2382 */ 2383 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2384 continue; 2385 if (fp == fdp->fd_ofiles[fd].fde_file) 2386 break; 2387 fdrop(fp, curthread); 2388 } 2389 *fpp = fp; 2390 if (haverightsp != NULL) { 2391 #ifdef CAPABILITIES 2392 *haverightsp = haverights; 2393 #else 2394 CAP_ALL(haverightsp); 2395 #endif 2396 } 2397 return (0); 2398 } 2399 2400 /* 2401 * Extract the file pointer associated with the specified descriptor for the 2402 * current user process. 2403 * 2404 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2405 * returned. 2406 * 2407 * File's rights will be checked against the capability rights mask. 2408 * 2409 * If an error occured the non-zero error is returned and *fpp is set to 2410 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2411 * responsible for fdrop(). 2412 */ 2413 static __inline int 2414 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2415 cap_rights_t *needrightsp, u_char *maxprotp) 2416 { 2417 struct filedesc *fdp; 2418 struct file *fp; 2419 cap_rights_t haverights, needrights; 2420 int error; 2421 2422 *fpp = NULL; 2423 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2424 return (EBADF); 2425 if (needrightsp != NULL) 2426 needrights = *needrightsp; 2427 else 2428 cap_rights_init(&needrights); 2429 if (maxprotp != NULL) 2430 cap_rights_set(&needrights, CAP_MMAP); 2431 error = fget_unlocked(fdp, fd, &needrights, 0, &fp, &haverights); 2432 if (error != 0) 2433 return (error); 2434 if (fp->f_ops == &badfileops) { 2435 fdrop(fp, td); 2436 return (EBADF); 2437 } 2438 2439 #ifdef CAPABILITIES 2440 /* 2441 * If requested, convert capability rights to access flags. 2442 */ 2443 if (maxprotp != NULL) 2444 *maxprotp = cap_rights_to_vmprot(&haverights); 2445 #else /* !CAPABILITIES */ 2446 if (maxprotp != NULL) 2447 *maxprotp = VM_PROT_ALL; 2448 #endif /* CAPABILITIES */ 2449 2450 /* 2451 * FREAD and FWRITE failure return EBADF as per POSIX. 2452 */ 2453 error = 0; 2454 switch (flags) { 2455 case FREAD: 2456 case FWRITE: 2457 if ((fp->f_flag & flags) == 0) 2458 error = EBADF; 2459 break; 2460 case FEXEC: 2461 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2462 ((fp->f_flag & FWRITE) != 0)) 2463 error = EBADF; 2464 break; 2465 case 0: 2466 break; 2467 default: 2468 KASSERT(0, ("wrong flags")); 2469 } 2470 2471 if (error != 0) { 2472 fdrop(fp, td); 2473 return (error); 2474 } 2475 2476 *fpp = fp; 2477 return (0); 2478 } 2479 2480 int 2481 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2482 { 2483 2484 return(_fget(td, fd, fpp, 0, rightsp, NULL)); 2485 } 2486 2487 int 2488 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2489 struct file **fpp) 2490 { 2491 2492 return (_fget(td, fd, fpp, 0, rightsp, maxprotp)); 2493 } 2494 2495 int 2496 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2497 { 2498 2499 return(_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2500 } 2501 2502 int 2503 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2504 { 2505 2506 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2507 } 2508 2509 /* 2510 * Like fget() but loads the underlying vnode, or returns an error if the 2511 * descriptor does not represent a vnode. Note that pipes use vnodes but 2512 * never have VM objects. The returned vnode will be vref()'d. 2513 * 2514 * XXX: what about the unused flags ? 2515 */ 2516 static __inline int 2517 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2518 struct vnode **vpp) 2519 { 2520 struct file *fp; 2521 int error; 2522 2523 *vpp = NULL; 2524 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2525 if (error != 0) 2526 return (error); 2527 if (fp->f_vnode == NULL) { 2528 error = EINVAL; 2529 } else { 2530 *vpp = fp->f_vnode; 2531 vref(*vpp); 2532 } 2533 fdrop(fp, td); 2534 2535 return (error); 2536 } 2537 2538 int 2539 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2540 { 2541 2542 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2543 } 2544 2545 int 2546 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2547 struct filecaps *havecaps, struct vnode **vpp) 2548 { 2549 struct filedesc *fdp; 2550 struct file *fp; 2551 #ifdef CAPABILITIES 2552 int error; 2553 #endif 2554 2555 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2556 return (EBADF); 2557 2558 fp = fget_locked(fdp, fd); 2559 if (fp == NULL || fp->f_ops == &badfileops) 2560 return (EBADF); 2561 2562 #ifdef CAPABILITIES 2563 if (needrightsp != NULL) { 2564 error = cap_check(cap_rights(fdp, fd), needrightsp); 2565 if (error != 0) 2566 return (error); 2567 } 2568 #endif 2569 2570 if (fp->f_vnode == NULL) 2571 return (EINVAL); 2572 2573 *vpp = fp->f_vnode; 2574 vref(*vpp); 2575 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2576 2577 return (0); 2578 } 2579 2580 int 2581 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2582 { 2583 2584 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2585 } 2586 2587 int 2588 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2589 { 2590 2591 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2592 } 2593 2594 #ifdef notyet 2595 int 2596 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2597 struct vnode **vpp) 2598 { 2599 2600 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2601 } 2602 #endif 2603 2604 /* 2605 * Like fget() but loads the underlying socket, or returns an error if the 2606 * descriptor does not represent a socket. 2607 * 2608 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2609 * in the future. 2610 * 2611 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2612 * on their file descriptor reference to prevent the socket from being free'd 2613 * during use. 2614 */ 2615 int 2616 fgetsock(struct thread *td, int fd, cap_rights_t *rightsp, struct socket **spp, 2617 u_int *fflagp) 2618 { 2619 struct file *fp; 2620 int error; 2621 2622 *spp = NULL; 2623 if (fflagp != NULL) 2624 *fflagp = 0; 2625 if ((error = _fget(td, fd, &fp, 0, rightsp, NULL)) != 0) 2626 return (error); 2627 if (fp->f_type != DTYPE_SOCKET) { 2628 error = ENOTSOCK; 2629 } else { 2630 *spp = fp->f_data; 2631 if (fflagp) 2632 *fflagp = fp->f_flag; 2633 SOCK_LOCK(*spp); 2634 soref(*spp); 2635 SOCK_UNLOCK(*spp); 2636 } 2637 fdrop(fp, td); 2638 2639 return (error); 2640 } 2641 2642 /* 2643 * Drop the reference count on the socket and XXX release the SX lock in the 2644 * future. The last reference closes the socket. 2645 * 2646 * Note: fputsock() is deprecated, see comment for fgetsock(). 2647 */ 2648 void 2649 fputsock(struct socket *so) 2650 { 2651 2652 ACCEPT_LOCK(); 2653 SOCK_LOCK(so); 2654 CURVNET_SET(so->so_vnet); 2655 sorele(so); 2656 CURVNET_RESTORE(); 2657 } 2658 2659 /* 2660 * Handle the last reference to a file being closed. 2661 */ 2662 int 2663 _fdrop(struct file *fp, struct thread *td) 2664 { 2665 int error; 2666 2667 error = 0; 2668 if (fp->f_count != 0) 2669 panic("fdrop: count %d", fp->f_count); 2670 if (fp->f_ops != &badfileops) 2671 error = fo_close(fp, td); 2672 atomic_subtract_int(&openfiles, 1); 2673 crfree(fp->f_cred); 2674 free(fp->f_advice, M_FADVISE); 2675 uma_zfree(file_zone, fp); 2676 2677 return (error); 2678 } 2679 2680 /* 2681 * Apply an advisory lock on a file descriptor. 2682 * 2683 * Just attempt to get a record lock of the requested type on the entire file 2684 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2685 */ 2686 #ifndef _SYS_SYSPROTO_H_ 2687 struct flock_args { 2688 int fd; 2689 int how; 2690 }; 2691 #endif 2692 /* ARGSUSED */ 2693 int 2694 sys_flock(struct thread *td, struct flock_args *uap) 2695 { 2696 struct file *fp; 2697 struct vnode *vp; 2698 struct flock lf; 2699 cap_rights_t rights; 2700 int error; 2701 2702 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2703 if (error != 0) 2704 return (error); 2705 if (fp->f_type != DTYPE_VNODE) { 2706 fdrop(fp, td); 2707 return (EOPNOTSUPP); 2708 } 2709 2710 vp = fp->f_vnode; 2711 lf.l_whence = SEEK_SET; 2712 lf.l_start = 0; 2713 lf.l_len = 0; 2714 if (uap->how & LOCK_UN) { 2715 lf.l_type = F_UNLCK; 2716 atomic_clear_int(&fp->f_flag, FHASLOCK); 2717 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2718 goto done2; 2719 } 2720 if (uap->how & LOCK_EX) 2721 lf.l_type = F_WRLCK; 2722 else if (uap->how & LOCK_SH) 2723 lf.l_type = F_RDLCK; 2724 else { 2725 error = EBADF; 2726 goto done2; 2727 } 2728 atomic_set_int(&fp->f_flag, FHASLOCK); 2729 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2730 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2731 done2: 2732 fdrop(fp, td); 2733 return (error); 2734 } 2735 /* 2736 * Duplicate the specified descriptor to a free descriptor. 2737 */ 2738 int 2739 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2740 int openerror, int *indxp) 2741 { 2742 struct file *fp; 2743 int error, indx; 2744 2745 KASSERT(openerror == ENODEV || openerror == ENXIO, 2746 ("unexpected error %d in %s", openerror, __func__)); 2747 2748 /* 2749 * If the to-be-dup'd fd number is greater than the allowed number 2750 * of file descriptors, or the fd to be dup'd has already been 2751 * closed, then reject. 2752 */ 2753 FILEDESC_XLOCK(fdp); 2754 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2755 FILEDESC_XUNLOCK(fdp); 2756 return (EBADF); 2757 } 2758 2759 error = fdalloc(td, 0, &indx); 2760 if (error != 0) { 2761 FILEDESC_XUNLOCK(fdp); 2762 return (error); 2763 } 2764 2765 /* 2766 * There are two cases of interest here. 2767 * 2768 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2769 * 2770 * For ENXIO steal away the file structure from (dfd) and store it in 2771 * (indx). (dfd) is effectively closed by this operation. 2772 */ 2773 switch (openerror) { 2774 case ENODEV: 2775 /* 2776 * Check that the mode the file is being opened for is a 2777 * subset of the mode of the existing descriptor. 2778 */ 2779 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2780 fdunused(fdp, indx); 2781 FILEDESC_XUNLOCK(fdp); 2782 return (EACCES); 2783 } 2784 fhold(fp); 2785 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2786 filecaps_copy(&fdp->fd_ofiles[dfd].fde_caps, 2787 &fdp->fd_ofiles[indx].fde_caps); 2788 break; 2789 case ENXIO: 2790 /* 2791 * Steal away the file pointer from dfd and stuff it into indx. 2792 */ 2793 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2794 bzero(&fdp->fd_ofiles[dfd], sizeof(fdp->fd_ofiles[dfd])); 2795 fdunused(fdp, dfd); 2796 break; 2797 } 2798 FILEDESC_XUNLOCK(fdp); 2799 *indxp = indx; 2800 return (0); 2801 } 2802 2803 /* 2804 * Scan all active processes and prisons to see if any of them have a current 2805 * or root directory of `olddp'. If so, replace them with the new mount point. 2806 */ 2807 void 2808 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2809 { 2810 struct filedesc *fdp; 2811 struct prison *pr; 2812 struct proc *p; 2813 int nrele; 2814 2815 if (vrefcnt(olddp) == 1) 2816 return; 2817 nrele = 0; 2818 sx_slock(&allproc_lock); 2819 FOREACH_PROC_IN_SYSTEM(p) { 2820 fdp = fdhold(p); 2821 if (fdp == NULL) 2822 continue; 2823 FILEDESC_XLOCK(fdp); 2824 if (fdp->fd_cdir == olddp) { 2825 vref(newdp); 2826 fdp->fd_cdir = newdp; 2827 nrele++; 2828 } 2829 if (fdp->fd_rdir == olddp) { 2830 vref(newdp); 2831 fdp->fd_rdir = newdp; 2832 nrele++; 2833 } 2834 if (fdp->fd_jdir == olddp) { 2835 vref(newdp); 2836 fdp->fd_jdir = newdp; 2837 nrele++; 2838 } 2839 FILEDESC_XUNLOCK(fdp); 2840 fddrop(fdp); 2841 } 2842 sx_sunlock(&allproc_lock); 2843 if (rootvnode == olddp) { 2844 vref(newdp); 2845 rootvnode = newdp; 2846 nrele++; 2847 } 2848 mtx_lock(&prison0.pr_mtx); 2849 if (prison0.pr_root == olddp) { 2850 vref(newdp); 2851 prison0.pr_root = newdp; 2852 nrele++; 2853 } 2854 mtx_unlock(&prison0.pr_mtx); 2855 sx_slock(&allprison_lock); 2856 TAILQ_FOREACH(pr, &allprison, pr_list) { 2857 mtx_lock(&pr->pr_mtx); 2858 if (pr->pr_root == olddp) { 2859 vref(newdp); 2860 pr->pr_root = newdp; 2861 nrele++; 2862 } 2863 mtx_unlock(&pr->pr_mtx); 2864 } 2865 sx_sunlock(&allprison_lock); 2866 while (nrele--) 2867 vrele(olddp); 2868 } 2869 2870 struct filedesc_to_leader * 2871 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2872 { 2873 struct filedesc_to_leader *fdtol; 2874 2875 fdtol = malloc(sizeof(struct filedesc_to_leader), 2876 M_FILEDESC_TO_LEADER, 2877 M_WAITOK); 2878 fdtol->fdl_refcount = 1; 2879 fdtol->fdl_holdcount = 0; 2880 fdtol->fdl_wakeup = 0; 2881 fdtol->fdl_leader = leader; 2882 if (old != NULL) { 2883 FILEDESC_XLOCK(fdp); 2884 fdtol->fdl_next = old->fdl_next; 2885 fdtol->fdl_prev = old; 2886 old->fdl_next = fdtol; 2887 fdtol->fdl_next->fdl_prev = fdtol; 2888 FILEDESC_XUNLOCK(fdp); 2889 } else { 2890 fdtol->fdl_next = fdtol; 2891 fdtol->fdl_prev = fdtol; 2892 } 2893 return (fdtol); 2894 } 2895 2896 /* 2897 * Get file structures globally. 2898 */ 2899 static int 2900 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2901 { 2902 struct xfile xf; 2903 struct filedesc *fdp; 2904 struct file *fp; 2905 struct proc *p; 2906 int error, n; 2907 2908 error = sysctl_wire_old_buffer(req, 0); 2909 if (error != 0) 2910 return (error); 2911 if (req->oldptr == NULL) { 2912 n = 0; 2913 sx_slock(&allproc_lock); 2914 FOREACH_PROC_IN_SYSTEM(p) { 2915 if (p->p_state == PRS_NEW) 2916 continue; 2917 fdp = fdhold(p); 2918 if (fdp == NULL) 2919 continue; 2920 /* overestimates sparse tables. */ 2921 if (fdp->fd_lastfile > 0) 2922 n += fdp->fd_lastfile; 2923 fddrop(fdp); 2924 } 2925 sx_sunlock(&allproc_lock); 2926 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2927 } 2928 error = 0; 2929 bzero(&xf, sizeof(xf)); 2930 xf.xf_size = sizeof(xf); 2931 sx_slock(&allproc_lock); 2932 FOREACH_PROC_IN_SYSTEM(p) { 2933 PROC_LOCK(p); 2934 if (p->p_state == PRS_NEW) { 2935 PROC_UNLOCK(p); 2936 continue; 2937 } 2938 if (p_cansee(req->td, p) != 0) { 2939 PROC_UNLOCK(p); 2940 continue; 2941 } 2942 xf.xf_pid = p->p_pid; 2943 xf.xf_uid = p->p_ucred->cr_uid; 2944 PROC_UNLOCK(p); 2945 fdp = fdhold(p); 2946 if (fdp == NULL) 2947 continue; 2948 FILEDESC_SLOCK(fdp); 2949 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) { 2950 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 2951 continue; 2952 xf.xf_fd = n; 2953 xf.xf_file = fp; 2954 xf.xf_data = fp->f_data; 2955 xf.xf_vnode = fp->f_vnode; 2956 xf.xf_type = fp->f_type; 2957 xf.xf_count = fp->f_count; 2958 xf.xf_msgcount = 0; 2959 xf.xf_offset = foffset_get(fp); 2960 xf.xf_flag = fp->f_flag; 2961 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2962 if (error) 2963 break; 2964 } 2965 FILEDESC_SUNLOCK(fdp); 2966 fddrop(fdp); 2967 if (error) 2968 break; 2969 } 2970 sx_sunlock(&allproc_lock); 2971 return (error); 2972 } 2973 2974 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD, 2975 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2976 2977 #ifdef KINFO_OFILE_SIZE 2978 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 2979 #endif 2980 2981 #ifdef COMPAT_FREEBSD7 2982 static int 2983 export_vnode_for_osysctl(struct vnode *vp, int type, 2984 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 2985 { 2986 int error; 2987 char *fullpath, *freepath; 2988 2989 bzero(kif, sizeof(*kif)); 2990 kif->kf_structsize = sizeof(*kif); 2991 2992 vref(vp); 2993 kif->kf_fd = type; 2994 kif->kf_type = KF_TYPE_VNODE; 2995 /* This function only handles directories. */ 2996 if (vp->v_type != VDIR) { 2997 vrele(vp); 2998 return (ENOTDIR); 2999 } 3000 kif->kf_vnode_type = KF_VTYPE_VDIR; 3001 3002 /* 3003 * This is not a true file descriptor, so we set a bogus refcount 3004 * and offset to indicate these fields should be ignored. 3005 */ 3006 kif->kf_ref_count = -1; 3007 kif->kf_offset = -1; 3008 3009 freepath = NULL; 3010 fullpath = "-"; 3011 FILEDESC_SUNLOCK(fdp); 3012 vn_fullpath(curthread, vp, &fullpath, &freepath); 3013 vrele(vp); 3014 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3015 if (freepath != NULL) 3016 free(freepath, M_TEMP); 3017 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3018 FILEDESC_SLOCK(fdp); 3019 return (error); 3020 } 3021 3022 /* 3023 * Get per-process file descriptors for use by procstat(1), et al. 3024 */ 3025 static int 3026 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3027 { 3028 char *fullpath, *freepath; 3029 struct kinfo_ofile *kif; 3030 struct filedesc *fdp; 3031 int error, i, *name; 3032 struct shmfd *shmfd; 3033 struct socket *so; 3034 struct vnode *vp; 3035 struct ksem *ks; 3036 struct file *fp; 3037 struct proc *p; 3038 struct tty *tp; 3039 3040 name = (int *)arg1; 3041 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3042 if (error != 0) 3043 return (error); 3044 fdp = fdhold(p); 3045 PROC_UNLOCK(p); 3046 if (fdp == NULL) 3047 return (ENOENT); 3048 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3049 FILEDESC_SLOCK(fdp); 3050 if (fdp->fd_cdir != NULL) 3051 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3052 fdp, req); 3053 if (fdp->fd_rdir != NULL) 3054 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3055 fdp, req); 3056 if (fdp->fd_jdir != NULL) 3057 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3058 fdp, req); 3059 for (i = 0; i < fdp->fd_nfiles; i++) { 3060 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3061 continue; 3062 bzero(kif, sizeof(*kif)); 3063 kif->kf_structsize = sizeof(*kif); 3064 ks = NULL; 3065 vp = NULL; 3066 so = NULL; 3067 tp = NULL; 3068 shmfd = NULL; 3069 kif->kf_fd = i; 3070 3071 switch (fp->f_type) { 3072 case DTYPE_VNODE: 3073 kif->kf_type = KF_TYPE_VNODE; 3074 vp = fp->f_vnode; 3075 break; 3076 3077 case DTYPE_SOCKET: 3078 kif->kf_type = KF_TYPE_SOCKET; 3079 so = fp->f_data; 3080 break; 3081 3082 case DTYPE_PIPE: 3083 kif->kf_type = KF_TYPE_PIPE; 3084 break; 3085 3086 case DTYPE_FIFO: 3087 kif->kf_type = KF_TYPE_FIFO; 3088 vp = fp->f_vnode; 3089 break; 3090 3091 case DTYPE_KQUEUE: 3092 kif->kf_type = KF_TYPE_KQUEUE; 3093 break; 3094 3095 case DTYPE_CRYPTO: 3096 kif->kf_type = KF_TYPE_CRYPTO; 3097 break; 3098 3099 case DTYPE_MQUEUE: 3100 kif->kf_type = KF_TYPE_MQUEUE; 3101 break; 3102 3103 case DTYPE_SHM: 3104 kif->kf_type = KF_TYPE_SHM; 3105 shmfd = fp->f_data; 3106 break; 3107 3108 case DTYPE_SEM: 3109 kif->kf_type = KF_TYPE_SEM; 3110 ks = fp->f_data; 3111 break; 3112 3113 case DTYPE_PTS: 3114 kif->kf_type = KF_TYPE_PTS; 3115 tp = fp->f_data; 3116 break; 3117 3118 #ifdef PROCDESC 3119 case DTYPE_PROCDESC: 3120 kif->kf_type = KF_TYPE_PROCDESC; 3121 break; 3122 #endif 3123 3124 default: 3125 kif->kf_type = KF_TYPE_UNKNOWN; 3126 break; 3127 } 3128 kif->kf_ref_count = fp->f_count; 3129 if (fp->f_flag & FREAD) 3130 kif->kf_flags |= KF_FLAG_READ; 3131 if (fp->f_flag & FWRITE) 3132 kif->kf_flags |= KF_FLAG_WRITE; 3133 if (fp->f_flag & FAPPEND) 3134 kif->kf_flags |= KF_FLAG_APPEND; 3135 if (fp->f_flag & FASYNC) 3136 kif->kf_flags |= KF_FLAG_ASYNC; 3137 if (fp->f_flag & FFSYNC) 3138 kif->kf_flags |= KF_FLAG_FSYNC; 3139 if (fp->f_flag & FNONBLOCK) 3140 kif->kf_flags |= KF_FLAG_NONBLOCK; 3141 if (fp->f_flag & O_DIRECT) 3142 kif->kf_flags |= KF_FLAG_DIRECT; 3143 if (fp->f_flag & FHASLOCK) 3144 kif->kf_flags |= KF_FLAG_HASLOCK; 3145 kif->kf_offset = foffset_get(fp); 3146 if (vp != NULL) { 3147 vref(vp); 3148 switch (vp->v_type) { 3149 case VNON: 3150 kif->kf_vnode_type = KF_VTYPE_VNON; 3151 break; 3152 case VREG: 3153 kif->kf_vnode_type = KF_VTYPE_VREG; 3154 break; 3155 case VDIR: 3156 kif->kf_vnode_type = KF_VTYPE_VDIR; 3157 break; 3158 case VBLK: 3159 kif->kf_vnode_type = KF_VTYPE_VBLK; 3160 break; 3161 case VCHR: 3162 kif->kf_vnode_type = KF_VTYPE_VCHR; 3163 break; 3164 case VLNK: 3165 kif->kf_vnode_type = KF_VTYPE_VLNK; 3166 break; 3167 case VSOCK: 3168 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3169 break; 3170 case VFIFO: 3171 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3172 break; 3173 case VBAD: 3174 kif->kf_vnode_type = KF_VTYPE_VBAD; 3175 break; 3176 default: 3177 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3178 break; 3179 } 3180 /* 3181 * It is OK to drop the filedesc lock here as we will 3182 * re-validate and re-evaluate its properties when 3183 * the loop continues. 3184 */ 3185 freepath = NULL; 3186 fullpath = "-"; 3187 FILEDESC_SUNLOCK(fdp); 3188 vn_fullpath(curthread, vp, &fullpath, &freepath); 3189 vrele(vp); 3190 strlcpy(kif->kf_path, fullpath, 3191 sizeof(kif->kf_path)); 3192 if (freepath != NULL) 3193 free(freepath, M_TEMP); 3194 FILEDESC_SLOCK(fdp); 3195 } 3196 if (so != NULL) { 3197 struct sockaddr *sa; 3198 3199 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3200 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3201 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3202 free(sa, M_SONAME); 3203 } 3204 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3205 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3206 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3207 free(sa, M_SONAME); 3208 } 3209 kif->kf_sock_domain = 3210 so->so_proto->pr_domain->dom_family; 3211 kif->kf_sock_type = so->so_type; 3212 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3213 } 3214 if (tp != NULL) { 3215 strlcpy(kif->kf_path, tty_devname(tp), 3216 sizeof(kif->kf_path)); 3217 } 3218 if (shmfd != NULL) 3219 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3220 if (ks != NULL && ksem_info != NULL) 3221 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL); 3222 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3223 if (error) 3224 break; 3225 } 3226 FILEDESC_SUNLOCK(fdp); 3227 fddrop(fdp); 3228 free(kif, M_TEMP); 3229 return (0); 3230 } 3231 3232 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD, 3233 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries"); 3234 #endif /* COMPAT_FREEBSD7 */ 3235 3236 #ifdef KINFO_FILE_SIZE 3237 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3238 #endif 3239 3240 struct export_fd_buf { 3241 struct filedesc *fdp; 3242 struct sbuf *sb; 3243 ssize_t remainder; 3244 struct kinfo_file kif; 3245 }; 3246 3247 static int 3248 export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt, 3249 int64_t offset, cap_rights_t *rightsp, struct export_fd_buf *efbuf) 3250 { 3251 struct { 3252 int fflag; 3253 int kf_fflag; 3254 } fflags_table[] = { 3255 { FAPPEND, KF_FLAG_APPEND }, 3256 { FASYNC, KF_FLAG_ASYNC }, 3257 { FFSYNC, KF_FLAG_FSYNC }, 3258 { FHASLOCK, KF_FLAG_HASLOCK }, 3259 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3260 { FREAD, KF_FLAG_READ }, 3261 { FWRITE, KF_FLAG_WRITE }, 3262 { O_CREAT, KF_FLAG_CREAT }, 3263 { O_DIRECT, KF_FLAG_DIRECT }, 3264 { O_EXCL, KF_FLAG_EXCL }, 3265 { O_EXEC, KF_FLAG_EXEC }, 3266 { O_EXLOCK, KF_FLAG_EXLOCK }, 3267 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3268 { O_SHLOCK, KF_FLAG_SHLOCK }, 3269 { O_TRUNC, KF_FLAG_TRUNC } 3270 }; 3271 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3272 struct kinfo_file *kif; 3273 struct vnode *vp; 3274 int error, locked; 3275 unsigned int i; 3276 3277 if (efbuf->remainder == 0) 3278 return (0); 3279 kif = &efbuf->kif; 3280 bzero(kif, sizeof(*kif)); 3281 locked = efbuf->fdp != NULL; 3282 switch (type) { 3283 case KF_TYPE_FIFO: 3284 case KF_TYPE_VNODE: 3285 if (locked) { 3286 FILEDESC_SUNLOCK(efbuf->fdp); 3287 locked = 0; 3288 } 3289 vp = (struct vnode *)data; 3290 error = fill_vnode_info(vp, kif); 3291 vrele(vp); 3292 break; 3293 case KF_TYPE_SOCKET: 3294 error = fill_socket_info((struct socket *)data, kif); 3295 break; 3296 case KF_TYPE_PIPE: 3297 error = fill_pipe_info((struct pipe *)data, kif); 3298 break; 3299 case KF_TYPE_PTS: 3300 error = fill_pts_info((struct tty *)data, kif); 3301 break; 3302 case KF_TYPE_PROCDESC: 3303 error = fill_procdesc_info((struct procdesc *)data, kif); 3304 break; 3305 case KF_TYPE_SEM: 3306 error = fill_sem_info((struct file *)data, kif); 3307 break; 3308 case KF_TYPE_SHM: 3309 error = fill_shm_info((struct file *)data, kif); 3310 break; 3311 default: 3312 error = 0; 3313 } 3314 if (error == 0) 3315 kif->kf_status |= KF_ATTR_VALID; 3316 3317 /* 3318 * Translate file access flags. 3319 */ 3320 for (i = 0; i < NFFLAGS; i++) 3321 if (fflags & fflags_table[i].fflag) 3322 kif->kf_flags |= fflags_table[i].kf_fflag; 3323 if (rightsp != NULL) 3324 kif->kf_cap_rights = *rightsp; 3325 else 3326 cap_rights_init(&kif->kf_cap_rights); 3327 kif->kf_fd = fd; 3328 kif->kf_type = type; 3329 kif->kf_ref_count = refcnt; 3330 kif->kf_offset = offset; 3331 /* Pack record size down */ 3332 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3333 strlen(kif->kf_path) + 1; 3334 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3335 if (efbuf->remainder != -1) { 3336 if (efbuf->remainder < kif->kf_structsize) { 3337 /* Terminate export. */ 3338 efbuf->remainder = 0; 3339 if (efbuf->fdp != NULL && !locked) 3340 FILEDESC_SLOCK(efbuf->fdp); 3341 return (0); 3342 } 3343 efbuf->remainder -= kif->kf_structsize; 3344 } 3345 if (locked) 3346 FILEDESC_SUNLOCK(efbuf->fdp); 3347 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize); 3348 if (efbuf->fdp != NULL) 3349 FILEDESC_SLOCK(efbuf->fdp); 3350 return (error); 3351 } 3352 3353 /* 3354 * Store a process file descriptor information to sbuf. 3355 * 3356 * Takes a locked proc as argument, and returns with the proc unlocked. 3357 */ 3358 int 3359 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3360 { 3361 struct file *fp; 3362 struct filedesc *fdp; 3363 struct export_fd_buf *efbuf; 3364 struct vnode *cttyvp, *textvp, *tracevp; 3365 int64_t offset; 3366 void *data; 3367 int error, i; 3368 int type, refcnt, fflags; 3369 cap_rights_t rights; 3370 3371 PROC_LOCK_ASSERT(p, MA_OWNED); 3372 3373 /* ktrace vnode */ 3374 tracevp = p->p_tracevp; 3375 if (tracevp != NULL) 3376 vref(tracevp); 3377 /* text vnode */ 3378 textvp = p->p_textvp; 3379 if (textvp != NULL) 3380 vref(textvp); 3381 /* Controlling tty. */ 3382 cttyvp = NULL; 3383 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3384 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3385 if (cttyvp != NULL) 3386 vref(cttyvp); 3387 } 3388 fdp = fdhold(p); 3389 PROC_UNLOCK(p); 3390 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3391 efbuf->fdp = NULL; 3392 efbuf->sb = sb; 3393 efbuf->remainder = maxlen; 3394 if (tracevp != NULL) 3395 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3396 FREAD | FWRITE, -1, -1, NULL, efbuf); 3397 if (textvp != NULL) 3398 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3399 FREAD, -1, -1, NULL, efbuf); 3400 if (cttyvp != NULL) 3401 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3402 FREAD | FWRITE, -1, -1, NULL, efbuf); 3403 error = 0; 3404 if (fdp == NULL) 3405 goto fail; 3406 efbuf->fdp = fdp; 3407 FILEDESC_SLOCK(fdp); 3408 /* working directory */ 3409 if (fdp->fd_cdir != NULL) { 3410 vref(fdp->fd_cdir); 3411 data = fdp->fd_cdir; 3412 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3413 FREAD, -1, -1, NULL, efbuf); 3414 } 3415 /* root directory */ 3416 if (fdp->fd_rdir != NULL) { 3417 vref(fdp->fd_rdir); 3418 data = fdp->fd_rdir; 3419 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3420 FREAD, -1, -1, NULL, efbuf); 3421 } 3422 /* jail directory */ 3423 if (fdp->fd_jdir != NULL) { 3424 vref(fdp->fd_jdir); 3425 data = fdp->fd_jdir; 3426 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3427 FREAD, -1, -1, NULL, efbuf); 3428 } 3429 for (i = 0; i < fdp->fd_nfiles; i++) { 3430 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3431 continue; 3432 data = NULL; 3433 #ifdef CAPABILITIES 3434 rights = *cap_rights(fdp, i); 3435 #else /* !CAPABILITIES */ 3436 cap_rights_init(&rights); 3437 #endif 3438 switch (fp->f_type) { 3439 case DTYPE_VNODE: 3440 type = KF_TYPE_VNODE; 3441 vref(fp->f_vnode); 3442 data = fp->f_vnode; 3443 break; 3444 3445 case DTYPE_SOCKET: 3446 type = KF_TYPE_SOCKET; 3447 data = fp->f_data; 3448 break; 3449 3450 case DTYPE_PIPE: 3451 type = KF_TYPE_PIPE; 3452 data = fp->f_data; 3453 break; 3454 3455 case DTYPE_FIFO: 3456 type = KF_TYPE_FIFO; 3457 vref(fp->f_vnode); 3458 data = fp->f_vnode; 3459 break; 3460 3461 case DTYPE_KQUEUE: 3462 type = KF_TYPE_KQUEUE; 3463 break; 3464 3465 case DTYPE_CRYPTO: 3466 type = KF_TYPE_CRYPTO; 3467 break; 3468 3469 case DTYPE_MQUEUE: 3470 type = KF_TYPE_MQUEUE; 3471 break; 3472 3473 case DTYPE_SHM: 3474 type = KF_TYPE_SHM; 3475 data = fp; 3476 break; 3477 3478 case DTYPE_SEM: 3479 type = KF_TYPE_SEM; 3480 data = fp; 3481 break; 3482 3483 case DTYPE_PTS: 3484 type = KF_TYPE_PTS; 3485 data = fp->f_data; 3486 break; 3487 3488 #ifdef PROCDESC 3489 case DTYPE_PROCDESC: 3490 type = KF_TYPE_PROCDESC; 3491 data = fp->f_data; 3492 break; 3493 #endif 3494 3495 default: 3496 type = KF_TYPE_UNKNOWN; 3497 break; 3498 } 3499 refcnt = fp->f_count; 3500 fflags = fp->f_flag; 3501 offset = foffset_get(fp); 3502 3503 /* 3504 * Create sysctl entry. 3505 * It is OK to drop the filedesc lock here as we will 3506 * re-validate and re-evaluate its properties when 3507 * the loop continues. 3508 */ 3509 error = export_fd_to_sb(data, type, i, fflags, refcnt, 3510 offset, &rights, efbuf); 3511 if (error != 0) 3512 break; 3513 } 3514 FILEDESC_SUNLOCK(fdp); 3515 fddrop(fdp); 3516 fail: 3517 free(efbuf, M_TEMP); 3518 return (error); 3519 } 3520 3521 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3522 3523 /* 3524 * Get per-process file descriptors for use by procstat(1), et al. 3525 */ 3526 static int 3527 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3528 { 3529 struct sbuf sb; 3530 struct proc *p; 3531 ssize_t maxlen; 3532 int error, error2, *name; 3533 3534 name = (int *)arg1; 3535 3536 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3537 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3538 if (error != 0) { 3539 sbuf_delete(&sb); 3540 return (error); 3541 } 3542 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3543 error = kern_proc_filedesc_out(p, &sb, maxlen); 3544 error2 = sbuf_finish(&sb); 3545 sbuf_delete(&sb); 3546 return (error != 0 ? error : error2); 3547 } 3548 3549 int 3550 vntype_to_kinfo(int vtype) 3551 { 3552 struct { 3553 int vtype; 3554 int kf_vtype; 3555 } vtypes_table[] = { 3556 { VBAD, KF_VTYPE_VBAD }, 3557 { VBLK, KF_VTYPE_VBLK }, 3558 { VCHR, KF_VTYPE_VCHR }, 3559 { VDIR, KF_VTYPE_VDIR }, 3560 { VFIFO, KF_VTYPE_VFIFO }, 3561 { VLNK, KF_VTYPE_VLNK }, 3562 { VNON, KF_VTYPE_VNON }, 3563 { VREG, KF_VTYPE_VREG }, 3564 { VSOCK, KF_VTYPE_VSOCK } 3565 }; 3566 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3567 unsigned int i; 3568 3569 /* 3570 * Perform vtype translation. 3571 */ 3572 for (i = 0; i < NVTYPES; i++) 3573 if (vtypes_table[i].vtype == vtype) 3574 break; 3575 if (i < NVTYPES) 3576 return (vtypes_table[i].kf_vtype); 3577 3578 return (KF_VTYPE_UNKNOWN); 3579 } 3580 3581 static int 3582 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3583 { 3584 struct vattr va; 3585 char *fullpath, *freepath; 3586 int error; 3587 3588 if (vp == NULL) 3589 return (1); 3590 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3591 freepath = NULL; 3592 fullpath = "-"; 3593 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3594 if (error == 0) { 3595 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3596 } 3597 if (freepath != NULL) 3598 free(freepath, M_TEMP); 3599 3600 /* 3601 * Retrieve vnode attributes. 3602 */ 3603 va.va_fsid = VNOVAL; 3604 va.va_rdev = NODEV; 3605 vn_lock(vp, LK_SHARED | LK_RETRY); 3606 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3607 VOP_UNLOCK(vp, 0); 3608 if (error != 0) 3609 return (error); 3610 if (va.va_fsid != VNOVAL) 3611 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3612 else 3613 kif->kf_un.kf_file.kf_file_fsid = 3614 vp->v_mount->mnt_stat.f_fsid.val[0]; 3615 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3616 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3617 kif->kf_un.kf_file.kf_file_size = va.va_size; 3618 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3619 return (0); 3620 } 3621 3622 static int 3623 fill_socket_info(struct socket *so, struct kinfo_file *kif) 3624 { 3625 struct sockaddr *sa; 3626 struct inpcb *inpcb; 3627 struct unpcb *unpcb; 3628 int error; 3629 3630 if (so == NULL) 3631 return (1); 3632 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3633 kif->kf_sock_type = so->so_type; 3634 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3635 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3636 switch(kif->kf_sock_domain) { 3637 case AF_INET: 3638 case AF_INET6: 3639 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3640 if (so->so_pcb != NULL) { 3641 inpcb = (struct inpcb *)(so->so_pcb); 3642 kif->kf_un.kf_sock.kf_sock_inpcb = 3643 (uintptr_t)inpcb->inp_ppcb; 3644 } 3645 } 3646 break; 3647 case AF_UNIX: 3648 if (so->so_pcb != NULL) { 3649 unpcb = (struct unpcb *)(so->so_pcb); 3650 if (unpcb->unp_conn) { 3651 kif->kf_un.kf_sock.kf_sock_unpconn = 3652 (uintptr_t)unpcb->unp_conn; 3653 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3654 so->so_rcv.sb_state; 3655 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3656 so->so_snd.sb_state; 3657 } 3658 } 3659 break; 3660 } 3661 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3662 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3663 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3664 free(sa, M_SONAME); 3665 } 3666 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3667 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3668 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3669 free(sa, M_SONAME); 3670 } 3671 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3672 sizeof(kif->kf_path)); 3673 return (0); 3674 } 3675 3676 static int 3677 fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3678 { 3679 3680 if (tp == NULL) 3681 return (1); 3682 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3683 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3684 return (0); 3685 } 3686 3687 static int 3688 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3689 { 3690 3691 if (pi == NULL) 3692 return (1); 3693 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3694 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3695 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3696 return (0); 3697 } 3698 3699 static int 3700 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3701 { 3702 3703 if (pdp == NULL) 3704 return (1); 3705 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3706 return (0); 3707 } 3708 3709 static int 3710 fill_sem_info(struct file *fp, struct kinfo_file *kif) 3711 { 3712 struct thread *td; 3713 struct stat sb; 3714 3715 td = curthread; 3716 if (fp->f_data == NULL) 3717 return (1); 3718 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3719 return (1); 3720 if (ksem_info == NULL) 3721 return (1); 3722 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path), 3723 &kif->kf_un.kf_sem.kf_sem_value); 3724 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode; 3725 return (0); 3726 } 3727 3728 static int 3729 fill_shm_info(struct file *fp, struct kinfo_file *kif) 3730 { 3731 struct thread *td; 3732 struct stat sb; 3733 3734 td = curthread; 3735 if (fp->f_data == NULL) 3736 return (1); 3737 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3738 return (1); 3739 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3740 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3741 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3742 return (0); 3743 } 3744 3745 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD, 3746 sysctl_kern_proc_filedesc, "Process filedesc entries"); 3747 3748 #ifdef DDB 3749 /* 3750 * For the purposes of debugging, generate a human-readable string for the 3751 * file type. 3752 */ 3753 static const char * 3754 file_type_to_name(short type) 3755 { 3756 3757 switch (type) { 3758 case 0: 3759 return ("zero"); 3760 case DTYPE_VNODE: 3761 return ("vnod"); 3762 case DTYPE_SOCKET: 3763 return ("sock"); 3764 case DTYPE_PIPE: 3765 return ("pipe"); 3766 case DTYPE_FIFO: 3767 return ("fifo"); 3768 case DTYPE_KQUEUE: 3769 return ("kque"); 3770 case DTYPE_CRYPTO: 3771 return ("crpt"); 3772 case DTYPE_MQUEUE: 3773 return ("mque"); 3774 case DTYPE_SHM: 3775 return ("shm"); 3776 case DTYPE_SEM: 3777 return ("ksem"); 3778 default: 3779 return ("unkn"); 3780 } 3781 } 3782 3783 /* 3784 * For the purposes of debugging, identify a process (if any, perhaps one of 3785 * many) that references the passed file in its file descriptor array. Return 3786 * NULL if none. 3787 */ 3788 static struct proc * 3789 file_to_first_proc(struct file *fp) 3790 { 3791 struct filedesc *fdp; 3792 struct proc *p; 3793 int n; 3794 3795 FOREACH_PROC_IN_SYSTEM(p) { 3796 if (p->p_state == PRS_NEW) 3797 continue; 3798 fdp = p->p_fd; 3799 if (fdp == NULL) 3800 continue; 3801 for (n = 0; n < fdp->fd_nfiles; n++) { 3802 if (fp == fdp->fd_ofiles[n].fde_file) 3803 return (p); 3804 } 3805 } 3806 return (NULL); 3807 } 3808 3809 static void 3810 db_print_file(struct file *fp, int header) 3811 { 3812 struct proc *p; 3813 3814 if (header) 3815 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3816 "File", "Type", "Data", "Flag", "GCFl", "Count", 3817 "MCount", "Vnode", "FPID", "FCmd"); 3818 p = file_to_first_proc(fp); 3819 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3820 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3821 0, fp->f_count, 0, fp->f_vnode, 3822 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3823 } 3824 3825 DB_SHOW_COMMAND(file, db_show_file) 3826 { 3827 struct file *fp; 3828 3829 if (!have_addr) { 3830 db_printf("usage: show file <addr>\n"); 3831 return; 3832 } 3833 fp = (struct file *)addr; 3834 db_print_file(fp, 1); 3835 } 3836 3837 DB_SHOW_COMMAND(files, db_show_files) 3838 { 3839 struct filedesc *fdp; 3840 struct file *fp; 3841 struct proc *p; 3842 int header; 3843 int n; 3844 3845 header = 1; 3846 FOREACH_PROC_IN_SYSTEM(p) { 3847 if (p->p_state == PRS_NEW) 3848 continue; 3849 if ((fdp = p->p_fd) == NULL) 3850 continue; 3851 for (n = 0; n < fdp->fd_nfiles; ++n) { 3852 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3853 continue; 3854 db_print_file(fp, header); 3855 header = 0; 3856 } 3857 } 3858 } 3859 #endif 3860 3861 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3862 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3863 3864 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3865 &maxfiles, 0, "Maximum number of files"); 3866 3867 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3868 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3869 3870 /* ARGSUSED*/ 3871 static void 3872 filelistinit(void *dummy) 3873 { 3874 3875 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3876 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3877 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3878 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3879 } 3880 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3881 3882 /*-------------------------------------------------------------------*/ 3883 3884 static int 3885 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3886 int flags, struct thread *td) 3887 { 3888 3889 return (EBADF); 3890 } 3891 3892 static int 3893 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3894 struct thread *td) 3895 { 3896 3897 return (EINVAL); 3898 } 3899 3900 static int 3901 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3902 struct thread *td) 3903 { 3904 3905 return (EBADF); 3906 } 3907 3908 static int 3909 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3910 struct thread *td) 3911 { 3912 3913 return (0); 3914 } 3915 3916 static int 3917 badfo_kqfilter(struct file *fp, struct knote *kn) 3918 { 3919 3920 return (EBADF); 3921 } 3922 3923 static int 3924 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3925 struct thread *td) 3926 { 3927 3928 return (EBADF); 3929 } 3930 3931 static int 3932 badfo_close(struct file *fp, struct thread *td) 3933 { 3934 3935 return (EBADF); 3936 } 3937 3938 static int 3939 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3940 struct thread *td) 3941 { 3942 3943 return (EBADF); 3944 } 3945 3946 static int 3947 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3948 struct thread *td) 3949 { 3950 3951 return (EBADF); 3952 } 3953 3954 static int 3955 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3956 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3957 int kflags, struct thread *td) 3958 { 3959 3960 return (EBADF); 3961 } 3962 3963 struct fileops badfileops = { 3964 .fo_read = badfo_readwrite, 3965 .fo_write = badfo_readwrite, 3966 .fo_truncate = badfo_truncate, 3967 .fo_ioctl = badfo_ioctl, 3968 .fo_poll = badfo_poll, 3969 .fo_kqfilter = badfo_kqfilter, 3970 .fo_stat = badfo_stat, 3971 .fo_close = badfo_close, 3972 .fo_chmod = badfo_chmod, 3973 .fo_chown = badfo_chown, 3974 .fo_sendfile = badfo_sendfile, 3975 }; 3976 3977 int 3978 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3979 struct thread *td) 3980 { 3981 3982 return (EINVAL); 3983 } 3984 3985 int 3986 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3987 struct thread *td) 3988 { 3989 3990 return (EINVAL); 3991 } 3992 3993 int 3994 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3995 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3996 int kflags, struct thread *td) 3997 { 3998 3999 return (EINVAL); 4000 } 4001 4002 /*-------------------------------------------------------------------*/ 4003 4004 /* 4005 * File Descriptor pseudo-device driver (/dev/fd/). 4006 * 4007 * Opening minor device N dup()s the file (if any) connected to file 4008 * descriptor N belonging to the calling process. Note that this driver 4009 * consists of only the ``open()'' routine, because all subsequent 4010 * references to this file will be direct to the other driver. 4011 * 4012 * XXX: we could give this one a cloning event handler if necessary. 4013 */ 4014 4015 /* ARGSUSED */ 4016 static int 4017 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 4018 { 4019 4020 /* 4021 * XXX Kludge: set curthread->td_dupfd to contain the value of the 4022 * the file descriptor being sought for duplication. The error 4023 * return ensures that the vnode for this device will be released 4024 * by vn_open. Open will detect this special error and take the 4025 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 4026 * will simply report the error. 4027 */ 4028 td->td_dupfd = dev2unit(dev); 4029 return (ENODEV); 4030 } 4031 4032 static struct cdevsw fildesc_cdevsw = { 4033 .d_version = D_VERSION, 4034 .d_open = fdopen, 4035 .d_name = "FD", 4036 }; 4037 4038 static void 4039 fildesc_drvinit(void *unused) 4040 { 4041 struct cdev *dev; 4042 4043 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4044 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4045 make_dev_alias(dev, "stdin"); 4046 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4047 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4048 make_dev_alias(dev, "stdout"); 4049 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4050 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4051 make_dev_alias(dev, "stderr"); 4052 } 4053 4054 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4055