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/limits.h> 59 #include <sys/lock.h> 60 #include <sys/malloc.h> 61 #include <sys/mman.h> 62 #include <sys/mount.h> 63 #include <sys/mqueue.h> 64 #include <sys/mutex.h> 65 #include <sys/namei.h> 66 #include <sys/selinfo.h> 67 #include <sys/pipe.h> 68 #include <sys/priv.h> 69 #include <sys/proc.h> 70 #include <sys/procdesc.h> 71 #include <sys/protosw.h> 72 #include <sys/racct.h> 73 #include <sys/resourcevar.h> 74 #include <sys/signalvar.h> 75 #include <sys/socketvar.h> 76 #include <sys/stat.h> 77 #include <sys/sx.h> 78 #include <sys/syscallsubr.h> 79 #include <sys/sysctl.h> 80 #include <sys/sysproto.h> 81 #include <sys/tty.h> 82 #include <sys/unistd.h> 83 #include <sys/un.h> 84 #include <sys/unpcb.h> 85 #include <sys/user.h> 86 #include <sys/vnode.h> 87 #ifdef KTRACE 88 #include <sys/ktrace.h> 89 #endif 90 91 #include <net/vnet.h> 92 93 #include <netinet/in.h> 94 #include <netinet/in_pcb.h> 95 96 #include <security/audit/audit.h> 97 98 #include <vm/uma.h> 99 #include <vm/vm.h> 100 101 #include <ddb/ddb.h> 102 103 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 104 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 105 "file desc to leader structures"); 106 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 107 108 MALLOC_DECLARE(M_FADVISE); 109 110 static uma_zone_t file_zone; 111 112 113 /* Flags for do_dup() */ 114 #define DUP_FIXED 0x1 /* Force fixed allocation */ 115 #define DUP_FCNTL 0x2 /* fcntl()-style errors */ 116 117 static int do_dup(struct thread *td, int flags, int old, int new, 118 register_t *retval); 119 static int fd_first_free(struct filedesc *, int, int); 120 static int fd_last_used(struct filedesc *, int, int); 121 static void fdgrowtable(struct filedesc *, int); 122 static void fdunused(struct filedesc *fdp, int fd); 123 static void fdused(struct filedesc *fdp, int fd); 124 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); 125 static int fill_socket_info(struct socket *so, struct kinfo_file *kif); 126 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif); 127 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); 128 static int fill_procdesc_info(struct procdesc *pdp, 129 struct kinfo_file *kif); 130 static int fill_shm_info(struct file *fp, struct kinfo_file *kif); 131 132 /* 133 * A process is initially started out with NDFILE descriptors stored within 134 * this structure, selected to be enough for typical applications based on 135 * the historical limit of 20 open files (and the usage of descriptors by 136 * shells). If these descriptors are exhausted, a larger descriptor table 137 * may be allocated, up to a process' resource limit; the internal arrays 138 * are then unused. 139 */ 140 #define NDFILE 20 141 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 142 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 143 #define NDSLOT(x) ((x) / NDENTRIES) 144 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 145 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 146 147 /* 148 * Storage required per open file descriptor. 149 */ 150 #define OFILESIZE (sizeof(struct file *) + sizeof(char)) 151 152 /* 153 * Storage to hold unused ofiles that need to be reclaimed. 154 */ 155 struct freetable { 156 struct file **ft_table; 157 SLIST_ENTRY(freetable) ft_next; 158 }; 159 160 /* 161 * Basic allocation of descriptors: 162 * one of the above, plus arrays for NDFILE descriptors. 163 */ 164 struct filedesc0 { 165 struct filedesc fd_fd; 166 /* 167 * ofiles which need to be reclaimed on free. 168 */ 169 SLIST_HEAD(,freetable) fd_free; 170 /* 171 * These arrays are used when the number of open files is 172 * <= NDFILE, and are then pointed to by the pointers above. 173 */ 174 struct file *fd_dfiles[NDFILE]; 175 char fd_dfileflags[NDFILE]; 176 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 177 }; 178 179 /* 180 * Descriptor management. 181 */ 182 volatile int openfiles; /* actual number of open files */ 183 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 184 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 185 186 /* A mutex to protect the association between a proc and filedesc. */ 187 static struct mtx fdesc_mtx; 188 189 /* 190 * Find the first zero bit in the given bitmap, starting at low and not 191 * exceeding size - 1. 192 */ 193 static int 194 fd_first_free(struct filedesc *fdp, int low, int size) 195 { 196 NDSLOTTYPE *map = fdp->fd_map; 197 NDSLOTTYPE mask; 198 int off, maxoff; 199 200 if (low >= size) 201 return (low); 202 203 off = NDSLOT(low); 204 if (low % NDENTRIES) { 205 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 206 if ((mask &= ~map[off]) != 0UL) 207 return (off * NDENTRIES + ffsl(mask) - 1); 208 ++off; 209 } 210 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 211 if (map[off] != ~0UL) 212 return (off * NDENTRIES + ffsl(~map[off]) - 1); 213 return (size); 214 } 215 216 /* 217 * Find the highest non-zero bit in the given bitmap, starting at low and 218 * not exceeding size - 1. 219 */ 220 static int 221 fd_last_used(struct filedesc *fdp, int low, int size) 222 { 223 NDSLOTTYPE *map = fdp->fd_map; 224 NDSLOTTYPE mask; 225 int off, minoff; 226 227 if (low >= size) 228 return (-1); 229 230 off = NDSLOT(size); 231 if (size % NDENTRIES) { 232 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 233 if ((mask &= map[off]) != 0) 234 return (off * NDENTRIES + flsl(mask) - 1); 235 --off; 236 } 237 for (minoff = NDSLOT(low); off >= minoff; --off) 238 if (map[off] != 0) 239 return (off * NDENTRIES + flsl(map[off]) - 1); 240 return (low - 1); 241 } 242 243 static int 244 fdisused(struct filedesc *fdp, int fd) 245 { 246 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 247 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 248 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 249 } 250 251 /* 252 * Mark a file descriptor as used. 253 */ 254 static void 255 fdused(struct filedesc *fdp, int fd) 256 { 257 258 FILEDESC_XLOCK_ASSERT(fdp); 259 KASSERT(!fdisused(fdp, fd), 260 ("fd already used")); 261 262 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 263 if (fd > fdp->fd_lastfile) 264 fdp->fd_lastfile = fd; 265 if (fd == fdp->fd_freefile) 266 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 267 } 268 269 /* 270 * Mark a file descriptor as unused. 271 */ 272 static void 273 fdunused(struct filedesc *fdp, int fd) 274 { 275 276 FILEDESC_XLOCK_ASSERT(fdp); 277 KASSERT(fdisused(fdp, fd), 278 ("fd is already unused")); 279 KASSERT(fdp->fd_ofiles[fd] == NULL, 280 ("fd is still in use")); 281 282 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 283 if (fd < fdp->fd_freefile) 284 fdp->fd_freefile = fd; 285 if (fd == fdp->fd_lastfile) 286 fdp->fd_lastfile = fd_last_used(fdp, 0, fd); 287 } 288 289 /* 290 * System calls on descriptors. 291 */ 292 #ifndef _SYS_SYSPROTO_H_ 293 struct getdtablesize_args { 294 int dummy; 295 }; 296 #endif 297 /* ARGSUSED */ 298 int 299 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 300 { 301 struct proc *p = td->td_proc; 302 uint64_t lim; 303 304 PROC_LOCK(p); 305 td->td_retval[0] = 306 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 307 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 308 PROC_UNLOCK(p); 309 if (lim < td->td_retval[0]) 310 td->td_retval[0] = lim; 311 return (0); 312 } 313 314 /* 315 * Duplicate a file descriptor to a particular value. 316 * 317 * Note: keep in mind that a potential race condition exists when closing 318 * descriptors from a shared descriptor table (via rfork). 319 */ 320 #ifndef _SYS_SYSPROTO_H_ 321 struct dup2_args { 322 u_int from; 323 u_int to; 324 }; 325 #endif 326 /* ARGSUSED */ 327 int 328 sys_dup2(struct thread *td, struct dup2_args *uap) 329 { 330 331 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 332 td->td_retval)); 333 } 334 335 /* 336 * Duplicate a file descriptor. 337 */ 338 #ifndef _SYS_SYSPROTO_H_ 339 struct dup_args { 340 u_int fd; 341 }; 342 #endif 343 /* ARGSUSED */ 344 int 345 sys_dup(struct thread *td, struct dup_args *uap) 346 { 347 348 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 349 } 350 351 /* 352 * The file control system call. 353 */ 354 #ifndef _SYS_SYSPROTO_H_ 355 struct fcntl_args { 356 int fd; 357 int cmd; 358 long arg; 359 }; 360 #endif 361 /* ARGSUSED */ 362 int 363 sys_fcntl(struct thread *td, struct fcntl_args *uap) 364 { 365 struct flock fl; 366 struct oflock ofl; 367 intptr_t arg; 368 int error; 369 int cmd; 370 371 error = 0; 372 cmd = uap->cmd; 373 switch (uap->cmd) { 374 case F_OGETLK: 375 case F_OSETLK: 376 case F_OSETLKW: 377 /* 378 * Convert old flock structure to new. 379 */ 380 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 381 fl.l_start = ofl.l_start; 382 fl.l_len = ofl.l_len; 383 fl.l_pid = ofl.l_pid; 384 fl.l_type = ofl.l_type; 385 fl.l_whence = ofl.l_whence; 386 fl.l_sysid = 0; 387 388 switch (uap->cmd) { 389 case F_OGETLK: 390 cmd = F_GETLK; 391 break; 392 case F_OSETLK: 393 cmd = F_SETLK; 394 break; 395 case F_OSETLKW: 396 cmd = F_SETLKW; 397 break; 398 } 399 arg = (intptr_t)&fl; 400 break; 401 case F_GETLK: 402 case F_SETLK: 403 case F_SETLKW: 404 case F_SETLK_REMOTE: 405 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 406 arg = (intptr_t)&fl; 407 break; 408 default: 409 arg = uap->arg; 410 break; 411 } 412 if (error) 413 return (error); 414 error = kern_fcntl(td, uap->fd, cmd, arg); 415 if (error) 416 return (error); 417 if (uap->cmd == F_OGETLK) { 418 ofl.l_start = fl.l_start; 419 ofl.l_len = fl.l_len; 420 ofl.l_pid = fl.l_pid; 421 ofl.l_type = fl.l_type; 422 ofl.l_whence = fl.l_whence; 423 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 424 } else if (uap->cmd == F_GETLK) { 425 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 426 } 427 return (error); 428 } 429 430 static inline struct file * 431 fdtofp(int fd, struct filedesc *fdp) 432 { 433 struct file *fp; 434 435 FILEDESC_LOCK_ASSERT(fdp); 436 if ((unsigned)fd >= fdp->fd_nfiles || 437 (fp = fdp->fd_ofiles[fd]) == NULL) 438 return (NULL); 439 return (fp); 440 } 441 442 static inline int 443 fdunwrap(int fd, cap_rights_t rights, struct filedesc *fdp, struct file **fpp) 444 { 445 446 *fpp = fdtofp(fd, fdp); 447 if (*fpp == NULL) 448 return (EBADF); 449 450 #ifdef CAPABILITIES 451 if ((*fpp)->f_type == DTYPE_CAPABILITY) { 452 int err = cap_funwrap(*fpp, rights, fpp); 453 if (err != 0) { 454 *fpp = NULL; 455 return (err); 456 } 457 } 458 #endif /* CAPABILITIES */ 459 return (0); 460 } 461 462 int 463 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 464 { 465 struct filedesc *fdp; 466 struct flock *flp; 467 struct file *fp; 468 struct proc *p; 469 char *pop; 470 struct vnode *vp; 471 int error, flg, tmp; 472 int vfslocked; 473 u_int old, new; 474 uint64_t bsize; 475 476 vfslocked = 0; 477 error = 0; 478 flg = F_POSIX; 479 p = td->td_proc; 480 fdp = p->p_fd; 481 482 switch (cmd) { 483 case F_DUPFD: 484 tmp = arg; 485 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 486 break; 487 488 case F_DUP2FD: 489 tmp = arg; 490 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 491 break; 492 493 case F_GETFD: 494 FILEDESC_SLOCK(fdp); 495 if ((fp = fdtofp(fd, fdp)) == NULL) { 496 FILEDESC_SUNLOCK(fdp); 497 error = EBADF; 498 break; 499 } 500 pop = &fdp->fd_ofileflags[fd]; 501 td->td_retval[0] = (*pop & UF_EXCLOSE) ? FD_CLOEXEC : 0; 502 FILEDESC_SUNLOCK(fdp); 503 break; 504 505 case F_SETFD: 506 FILEDESC_XLOCK(fdp); 507 if ((fp = fdtofp(fd, fdp)) == NULL) { 508 FILEDESC_XUNLOCK(fdp); 509 error = EBADF; 510 break; 511 } 512 pop = &fdp->fd_ofileflags[fd]; 513 *pop = (*pop &~ UF_EXCLOSE) | 514 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 515 FILEDESC_XUNLOCK(fdp); 516 break; 517 518 case F_GETFL: 519 FILEDESC_SLOCK(fdp); 520 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); 521 if (error != 0) { 522 FILEDESC_SUNLOCK(fdp); 523 break; 524 } 525 td->td_retval[0] = OFLAGS(fp->f_flag); 526 FILEDESC_SUNLOCK(fdp); 527 break; 528 529 case F_SETFL: 530 FILEDESC_SLOCK(fdp); 531 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); 532 if (error != 0) { 533 FILEDESC_SUNLOCK(fdp); 534 break; 535 } 536 fhold(fp); 537 FILEDESC_SUNLOCK(fdp); 538 do { 539 tmp = flg = fp->f_flag; 540 tmp &= ~FCNTLFLAGS; 541 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 542 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 543 tmp = fp->f_flag & FNONBLOCK; 544 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 545 if (error) { 546 fdrop(fp, td); 547 break; 548 } 549 tmp = fp->f_flag & FASYNC; 550 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 551 if (error == 0) { 552 fdrop(fp, td); 553 break; 554 } 555 atomic_clear_int(&fp->f_flag, FNONBLOCK); 556 tmp = 0; 557 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 558 fdrop(fp, td); 559 break; 560 561 case F_GETOWN: 562 FILEDESC_SLOCK(fdp); 563 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); 564 if (error != 0) { 565 FILEDESC_SUNLOCK(fdp); 566 break; 567 } 568 fhold(fp); 569 FILEDESC_SUNLOCK(fdp); 570 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 571 if (error == 0) 572 td->td_retval[0] = tmp; 573 fdrop(fp, td); 574 break; 575 576 case F_SETOWN: 577 FILEDESC_SLOCK(fdp); 578 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); 579 if (error != 0) { 580 FILEDESC_SUNLOCK(fdp); 581 break; 582 } 583 fhold(fp); 584 FILEDESC_SUNLOCK(fdp); 585 tmp = arg; 586 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 587 fdrop(fp, td); 588 break; 589 590 case F_SETLK_REMOTE: 591 error = priv_check(td, PRIV_NFS_LOCKD); 592 if (error) 593 return (error); 594 flg = F_REMOTE; 595 goto do_setlk; 596 597 case F_SETLKW: 598 flg |= F_WAIT; 599 /* FALLTHROUGH F_SETLK */ 600 601 case F_SETLK: 602 do_setlk: 603 FILEDESC_SLOCK(fdp); 604 error = fdunwrap(fd, CAP_FLOCK, fdp, &fp); 605 if (error != 0) { 606 FILEDESC_SUNLOCK(fdp); 607 break; 608 } 609 if (fp->f_type != DTYPE_VNODE) { 610 FILEDESC_SUNLOCK(fdp); 611 error = EBADF; 612 break; 613 } 614 flp = (struct flock *)arg; 615 if (flp->l_whence == SEEK_CUR) { 616 if (fp->f_offset < 0 || 617 (flp->l_start > 0 && 618 fp->f_offset > OFF_MAX - flp->l_start)) { 619 FILEDESC_SUNLOCK(fdp); 620 error = EOVERFLOW; 621 break; 622 } 623 flp->l_start += fp->f_offset; 624 } 625 626 /* 627 * VOP_ADVLOCK() may block. 628 */ 629 fhold(fp); 630 FILEDESC_SUNLOCK(fdp); 631 vp = fp->f_vnode; 632 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 633 switch (flp->l_type) { 634 case F_RDLCK: 635 if ((fp->f_flag & FREAD) == 0) { 636 error = EBADF; 637 break; 638 } 639 PROC_LOCK(p->p_leader); 640 p->p_leader->p_flag |= P_ADVLOCK; 641 PROC_UNLOCK(p->p_leader); 642 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 643 flp, flg); 644 break; 645 case F_WRLCK: 646 if ((fp->f_flag & FWRITE) == 0) { 647 error = EBADF; 648 break; 649 } 650 PROC_LOCK(p->p_leader); 651 p->p_leader->p_flag |= P_ADVLOCK; 652 PROC_UNLOCK(p->p_leader); 653 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 654 flp, flg); 655 break; 656 case F_UNLCK: 657 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 658 flp, flg); 659 break; 660 case F_UNLCKSYS: 661 /* 662 * Temporary api for testing remote lock 663 * infrastructure. 664 */ 665 if (flg != F_REMOTE) { 666 error = EINVAL; 667 break; 668 } 669 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 670 F_UNLCKSYS, flp, flg); 671 break; 672 default: 673 error = EINVAL; 674 break; 675 } 676 VFS_UNLOCK_GIANT(vfslocked); 677 vfslocked = 0; 678 /* Check for race with close */ 679 FILEDESC_SLOCK(fdp); 680 if ((unsigned) fd >= fdp->fd_nfiles || 681 fp != fdp->fd_ofiles[fd]) { 682 FILEDESC_SUNLOCK(fdp); 683 flp->l_whence = SEEK_SET; 684 flp->l_start = 0; 685 flp->l_len = 0; 686 flp->l_type = F_UNLCK; 687 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 688 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 689 F_UNLCK, flp, F_POSIX); 690 VFS_UNLOCK_GIANT(vfslocked); 691 vfslocked = 0; 692 } else 693 FILEDESC_SUNLOCK(fdp); 694 fdrop(fp, td); 695 break; 696 697 case F_GETLK: 698 FILEDESC_SLOCK(fdp); 699 error = fdunwrap(fd, CAP_FLOCK, fdp, &fp); 700 if (error != 0) { 701 FILEDESC_SUNLOCK(fdp); 702 break; 703 } 704 if (fp->f_type != DTYPE_VNODE) { 705 FILEDESC_SUNLOCK(fdp); 706 error = EBADF; 707 break; 708 } 709 flp = (struct flock *)arg; 710 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 711 flp->l_type != F_UNLCK) { 712 FILEDESC_SUNLOCK(fdp); 713 error = EINVAL; 714 break; 715 } 716 if (flp->l_whence == SEEK_CUR) { 717 if ((flp->l_start > 0 && 718 fp->f_offset > OFF_MAX - flp->l_start) || 719 (flp->l_start < 0 && 720 fp->f_offset < OFF_MIN - flp->l_start)) { 721 FILEDESC_SUNLOCK(fdp); 722 error = EOVERFLOW; 723 break; 724 } 725 flp->l_start += fp->f_offset; 726 } 727 /* 728 * VOP_ADVLOCK() may block. 729 */ 730 fhold(fp); 731 FILEDESC_SUNLOCK(fdp); 732 vp = fp->f_vnode; 733 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 734 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 735 F_POSIX); 736 VFS_UNLOCK_GIANT(vfslocked); 737 vfslocked = 0; 738 fdrop(fp, td); 739 break; 740 741 case F_RDAHEAD: 742 arg = arg ? 128 * 1024: 0; 743 /* FALLTHROUGH */ 744 case F_READAHEAD: 745 FILEDESC_SLOCK(fdp); 746 if ((fp = fdtofp(fd, fdp)) == NULL) { 747 FILEDESC_SUNLOCK(fdp); 748 error = EBADF; 749 break; 750 } 751 if (fp->f_type != DTYPE_VNODE) { 752 FILEDESC_SUNLOCK(fdp); 753 error = EBADF; 754 break; 755 } 756 fhold(fp); 757 FILEDESC_SUNLOCK(fdp); 758 if (arg != 0) { 759 vp = fp->f_vnode; 760 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 761 error = vn_lock(vp, LK_SHARED); 762 if (error != 0) 763 goto readahead_vnlock_fail; 764 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 765 VOP_UNLOCK(vp, 0); 766 fp->f_seqcount = (arg + bsize - 1) / bsize; 767 do { 768 new = old = fp->f_flag; 769 new |= FRDAHEAD; 770 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 771 readahead_vnlock_fail: 772 VFS_UNLOCK_GIANT(vfslocked); 773 vfslocked = 0; 774 } else { 775 do { 776 new = old = fp->f_flag; 777 new &= ~FRDAHEAD; 778 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 779 } 780 fdrop(fp, td); 781 break; 782 783 default: 784 error = EINVAL; 785 break; 786 } 787 VFS_UNLOCK_GIANT(vfslocked); 788 return (error); 789 } 790 791 /* 792 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 793 */ 794 static int 795 do_dup(struct thread *td, int flags, int old, int new, 796 register_t *retval) 797 { 798 struct filedesc *fdp; 799 struct proc *p; 800 struct file *fp; 801 struct file *delfp; 802 int error, holdleaders, maxfd; 803 804 p = td->td_proc; 805 fdp = p->p_fd; 806 807 /* 808 * Verify we have a valid descriptor to dup from and possibly to 809 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 810 * return EINVAL when the new descriptor is out of bounds. 811 */ 812 if (old < 0) 813 return (EBADF); 814 if (new < 0) 815 return (flags & DUP_FCNTL ? EINVAL : EBADF); 816 PROC_LOCK(p); 817 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 818 PROC_UNLOCK(p); 819 if (new >= maxfd) 820 return (flags & DUP_FCNTL ? EINVAL : EMFILE); 821 822 FILEDESC_XLOCK(fdp); 823 if (old >= fdp->fd_nfiles || fdp->fd_ofiles[old] == NULL) { 824 FILEDESC_XUNLOCK(fdp); 825 return (EBADF); 826 } 827 if (flags & DUP_FIXED && old == new) { 828 *retval = new; 829 FILEDESC_XUNLOCK(fdp); 830 return (0); 831 } 832 fp = fdp->fd_ofiles[old]; 833 fhold(fp); 834 835 /* 836 * If the caller specified a file descriptor, make sure the file 837 * table is large enough to hold it, and grab it. Otherwise, just 838 * allocate a new descriptor the usual way. Since the filedesc 839 * lock may be temporarily dropped in the process, we have to look 840 * out for a race. 841 */ 842 if (flags & DUP_FIXED) { 843 if (new >= fdp->fd_nfiles) { 844 /* 845 * The resource limits are here instead of e.g. 846 * fdalloc(), because the file descriptor table may be 847 * shared between processes, so we can't really use 848 * racct_add()/racct_sub(). Instead of counting the 849 * number of actually allocated descriptors, just put 850 * the limit on the size of the file descriptor table. 851 */ 852 #ifdef RACCT 853 PROC_LOCK(p); 854 error = racct_set(p, RACCT_NOFILE, new + 1); 855 PROC_UNLOCK(p); 856 if (error != 0) { 857 FILEDESC_XUNLOCK(fdp); 858 fdrop(fp, td); 859 return (EMFILE); 860 } 861 #endif 862 fdgrowtable(fdp, new + 1); 863 } 864 if (fdp->fd_ofiles[new] == NULL) 865 fdused(fdp, new); 866 } else { 867 if ((error = fdalloc(td, new, &new)) != 0) { 868 FILEDESC_XUNLOCK(fdp); 869 fdrop(fp, td); 870 return (error); 871 } 872 } 873 874 /* 875 * If the old file changed out from under us then treat it as a 876 * bad file descriptor. Userland should do its own locking to 877 * avoid this case. 878 */ 879 if (fdp->fd_ofiles[old] != fp) { 880 /* we've allocated a descriptor which we won't use */ 881 if (fdp->fd_ofiles[new] == NULL) 882 fdunused(fdp, new); 883 FILEDESC_XUNLOCK(fdp); 884 fdrop(fp, td); 885 return (EBADF); 886 } 887 KASSERT(old != new, 888 ("new fd is same as old")); 889 890 /* 891 * Save info on the descriptor being overwritten. We cannot close 892 * it without introducing an ownership race for the slot, since we 893 * need to drop the filedesc lock to call closef(). 894 * 895 * XXX this duplicates parts of close(). 896 */ 897 delfp = fdp->fd_ofiles[new]; 898 holdleaders = 0; 899 if (delfp != NULL) { 900 if (td->td_proc->p_fdtol != NULL) { 901 /* 902 * Ask fdfree() to sleep to ensure that all relevant 903 * process leaders can be traversed in closef(). 904 */ 905 fdp->fd_holdleaderscount++; 906 holdleaders = 1; 907 } 908 } 909 910 /* 911 * Duplicate the source descriptor 912 */ 913 fdp->fd_ofiles[new] = fp; 914 fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] &~ UF_EXCLOSE; 915 if (new > fdp->fd_lastfile) 916 fdp->fd_lastfile = new; 917 *retval = new; 918 919 /* 920 * If we dup'd over a valid file, we now own the reference to it 921 * and must dispose of it using closef() semantics (as if a 922 * close() were performed on it). 923 * 924 * XXX this duplicates parts of close(). 925 */ 926 if (delfp != NULL) { 927 knote_fdclose(td, new); 928 if (delfp->f_type == DTYPE_MQUEUE) 929 mq_fdclose(td, new, delfp); 930 FILEDESC_XUNLOCK(fdp); 931 (void) closef(delfp, td); 932 if (holdleaders) { 933 FILEDESC_XLOCK(fdp); 934 fdp->fd_holdleaderscount--; 935 if (fdp->fd_holdleaderscount == 0 && 936 fdp->fd_holdleaderswakeup != 0) { 937 fdp->fd_holdleaderswakeup = 0; 938 wakeup(&fdp->fd_holdleaderscount); 939 } 940 FILEDESC_XUNLOCK(fdp); 941 } 942 } else { 943 FILEDESC_XUNLOCK(fdp); 944 } 945 return (0); 946 } 947 948 /* 949 * If sigio is on the list associated with a process or process group, 950 * disable signalling from the device, remove sigio from the list and 951 * free sigio. 952 */ 953 void 954 funsetown(struct sigio **sigiop) 955 { 956 struct sigio *sigio; 957 958 SIGIO_LOCK(); 959 sigio = *sigiop; 960 if (sigio == NULL) { 961 SIGIO_UNLOCK(); 962 return; 963 } 964 *(sigio->sio_myref) = NULL; 965 if ((sigio)->sio_pgid < 0) { 966 struct pgrp *pg = (sigio)->sio_pgrp; 967 PGRP_LOCK(pg); 968 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 969 sigio, sio_pgsigio); 970 PGRP_UNLOCK(pg); 971 } else { 972 struct proc *p = (sigio)->sio_proc; 973 PROC_LOCK(p); 974 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 975 sigio, sio_pgsigio); 976 PROC_UNLOCK(p); 977 } 978 SIGIO_UNLOCK(); 979 crfree(sigio->sio_ucred); 980 free(sigio, M_SIGIO); 981 } 982 983 /* 984 * Free a list of sigio structures. 985 * We only need to lock the SIGIO_LOCK because we have made ourselves 986 * inaccessible to callers of fsetown and therefore do not need to lock 987 * the proc or pgrp struct for the list manipulation. 988 */ 989 void 990 funsetownlst(struct sigiolst *sigiolst) 991 { 992 struct proc *p; 993 struct pgrp *pg; 994 struct sigio *sigio; 995 996 sigio = SLIST_FIRST(sigiolst); 997 if (sigio == NULL) 998 return; 999 p = NULL; 1000 pg = NULL; 1001 1002 /* 1003 * Every entry of the list should belong 1004 * to a single proc or pgrp. 1005 */ 1006 if (sigio->sio_pgid < 0) { 1007 pg = sigio->sio_pgrp; 1008 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 1009 } else /* if (sigio->sio_pgid > 0) */ { 1010 p = sigio->sio_proc; 1011 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 1012 } 1013 1014 SIGIO_LOCK(); 1015 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 1016 *(sigio->sio_myref) = NULL; 1017 if (pg != NULL) { 1018 KASSERT(sigio->sio_pgid < 0, 1019 ("Proc sigio in pgrp sigio list")); 1020 KASSERT(sigio->sio_pgrp == pg, 1021 ("Bogus pgrp in sigio list")); 1022 PGRP_LOCK(pg); 1023 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 1024 sio_pgsigio); 1025 PGRP_UNLOCK(pg); 1026 } else /* if (p != NULL) */ { 1027 KASSERT(sigio->sio_pgid > 0, 1028 ("Pgrp sigio in proc sigio list")); 1029 KASSERT(sigio->sio_proc == p, 1030 ("Bogus proc in sigio list")); 1031 PROC_LOCK(p); 1032 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 1033 sio_pgsigio); 1034 PROC_UNLOCK(p); 1035 } 1036 SIGIO_UNLOCK(); 1037 crfree(sigio->sio_ucred); 1038 free(sigio, M_SIGIO); 1039 SIGIO_LOCK(); 1040 } 1041 SIGIO_UNLOCK(); 1042 } 1043 1044 /* 1045 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1046 * 1047 * After permission checking, add a sigio structure to the sigio list for 1048 * the process or process group. 1049 */ 1050 int 1051 fsetown(pid_t pgid, struct sigio **sigiop) 1052 { 1053 struct proc *proc; 1054 struct pgrp *pgrp; 1055 struct sigio *sigio; 1056 int ret; 1057 1058 if (pgid == 0) { 1059 funsetown(sigiop); 1060 return (0); 1061 } 1062 1063 ret = 0; 1064 1065 /* Allocate and fill in the new sigio out of locks. */ 1066 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1067 sigio->sio_pgid = pgid; 1068 sigio->sio_ucred = crhold(curthread->td_ucred); 1069 sigio->sio_myref = sigiop; 1070 1071 sx_slock(&proctree_lock); 1072 if (pgid > 0) { 1073 proc = pfind(pgid); 1074 if (proc == NULL) { 1075 ret = ESRCH; 1076 goto fail; 1077 } 1078 1079 /* 1080 * Policy - Don't allow a process to FSETOWN a process 1081 * in another session. 1082 * 1083 * Remove this test to allow maximum flexibility or 1084 * restrict FSETOWN to the current process or process 1085 * group for maximum safety. 1086 */ 1087 PROC_UNLOCK(proc); 1088 if (proc->p_session != curthread->td_proc->p_session) { 1089 ret = EPERM; 1090 goto fail; 1091 } 1092 1093 pgrp = NULL; 1094 } else /* if (pgid < 0) */ { 1095 pgrp = pgfind(-pgid); 1096 if (pgrp == NULL) { 1097 ret = ESRCH; 1098 goto fail; 1099 } 1100 PGRP_UNLOCK(pgrp); 1101 1102 /* 1103 * Policy - Don't allow a process to FSETOWN a process 1104 * in another session. 1105 * 1106 * Remove this test to allow maximum flexibility or 1107 * restrict FSETOWN to the current process or process 1108 * group for maximum safety. 1109 */ 1110 if (pgrp->pg_session != curthread->td_proc->p_session) { 1111 ret = EPERM; 1112 goto fail; 1113 } 1114 1115 proc = NULL; 1116 } 1117 funsetown(sigiop); 1118 if (pgid > 0) { 1119 PROC_LOCK(proc); 1120 /* 1121 * Since funsetownlst() is called without the proctree 1122 * locked, we need to check for P_WEXIT. 1123 * XXX: is ESRCH correct? 1124 */ 1125 if ((proc->p_flag & P_WEXIT) != 0) { 1126 PROC_UNLOCK(proc); 1127 ret = ESRCH; 1128 goto fail; 1129 } 1130 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1131 sigio->sio_proc = proc; 1132 PROC_UNLOCK(proc); 1133 } else { 1134 PGRP_LOCK(pgrp); 1135 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1136 sigio->sio_pgrp = pgrp; 1137 PGRP_UNLOCK(pgrp); 1138 } 1139 sx_sunlock(&proctree_lock); 1140 SIGIO_LOCK(); 1141 *sigiop = sigio; 1142 SIGIO_UNLOCK(); 1143 return (0); 1144 1145 fail: 1146 sx_sunlock(&proctree_lock); 1147 crfree(sigio->sio_ucred); 1148 free(sigio, M_SIGIO); 1149 return (ret); 1150 } 1151 1152 /* 1153 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1154 */ 1155 pid_t 1156 fgetown(sigiop) 1157 struct sigio **sigiop; 1158 { 1159 pid_t pgid; 1160 1161 SIGIO_LOCK(); 1162 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1163 SIGIO_UNLOCK(); 1164 return (pgid); 1165 } 1166 1167 /* 1168 * Close a file descriptor. 1169 */ 1170 #ifndef _SYS_SYSPROTO_H_ 1171 struct close_args { 1172 int fd; 1173 }; 1174 #endif 1175 /* ARGSUSED */ 1176 int 1177 sys_close(td, uap) 1178 struct thread *td; 1179 struct close_args *uap; 1180 { 1181 1182 return (kern_close(td, uap->fd)); 1183 } 1184 1185 int 1186 kern_close(td, fd) 1187 struct thread *td; 1188 int fd; 1189 { 1190 struct filedesc *fdp; 1191 struct file *fp, *fp_object; 1192 int error; 1193 int holdleaders; 1194 1195 error = 0; 1196 holdleaders = 0; 1197 fdp = td->td_proc->p_fd; 1198 1199 AUDIT_SYSCLOSE(td, fd); 1200 1201 FILEDESC_XLOCK(fdp); 1202 if ((unsigned)fd >= fdp->fd_nfiles || 1203 (fp = fdp->fd_ofiles[fd]) == NULL) { 1204 FILEDESC_XUNLOCK(fdp); 1205 return (EBADF); 1206 } 1207 fdp->fd_ofiles[fd] = NULL; 1208 fdp->fd_ofileflags[fd] = 0; 1209 fdunused(fdp, fd); 1210 if (td->td_proc->p_fdtol != NULL) { 1211 /* 1212 * Ask fdfree() to sleep to ensure that all relevant 1213 * process leaders can be traversed in closef(). 1214 */ 1215 fdp->fd_holdleaderscount++; 1216 holdleaders = 1; 1217 } 1218 1219 /* 1220 * We now hold the fp reference that used to be owned by the 1221 * descriptor array. We have to unlock the FILEDESC *AFTER* 1222 * knote_fdclose to prevent a race of the fd getting opened, a knote 1223 * added, and deleteing a knote for the new fd. 1224 */ 1225 knote_fdclose(td, fd); 1226 1227 /* 1228 * When we're closing an fd with a capability, we need to notify 1229 * mqueue if the underlying object is of type mqueue. 1230 */ 1231 (void)cap_funwrap(fp, 0, &fp_object); 1232 if (fp_object->f_type == DTYPE_MQUEUE) 1233 mq_fdclose(td, fd, fp_object); 1234 FILEDESC_XUNLOCK(fdp); 1235 1236 error = closef(fp, td); 1237 if (holdleaders) { 1238 FILEDESC_XLOCK(fdp); 1239 fdp->fd_holdleaderscount--; 1240 if (fdp->fd_holdleaderscount == 0 && 1241 fdp->fd_holdleaderswakeup != 0) { 1242 fdp->fd_holdleaderswakeup = 0; 1243 wakeup(&fdp->fd_holdleaderscount); 1244 } 1245 FILEDESC_XUNLOCK(fdp); 1246 } 1247 return (error); 1248 } 1249 1250 /* 1251 * Close open file descriptors. 1252 */ 1253 #ifndef _SYS_SYSPROTO_H_ 1254 struct closefrom_args { 1255 int lowfd; 1256 }; 1257 #endif 1258 /* ARGSUSED */ 1259 int 1260 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1261 { 1262 struct filedesc *fdp; 1263 int fd; 1264 1265 fdp = td->td_proc->p_fd; 1266 AUDIT_ARG_FD(uap->lowfd); 1267 1268 /* 1269 * Treat negative starting file descriptor values identical to 1270 * closefrom(0) which closes all files. 1271 */ 1272 if (uap->lowfd < 0) 1273 uap->lowfd = 0; 1274 FILEDESC_SLOCK(fdp); 1275 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) { 1276 if (fdp->fd_ofiles[fd] != NULL) { 1277 FILEDESC_SUNLOCK(fdp); 1278 (void)kern_close(td, fd); 1279 FILEDESC_SLOCK(fdp); 1280 } 1281 } 1282 FILEDESC_SUNLOCK(fdp); 1283 return (0); 1284 } 1285 1286 #if defined(COMPAT_43) 1287 /* 1288 * Return status information about a file descriptor. 1289 */ 1290 #ifndef _SYS_SYSPROTO_H_ 1291 struct ofstat_args { 1292 int fd; 1293 struct ostat *sb; 1294 }; 1295 #endif 1296 /* ARGSUSED */ 1297 int 1298 ofstat(struct thread *td, struct ofstat_args *uap) 1299 { 1300 struct ostat oub; 1301 struct stat ub; 1302 int error; 1303 1304 error = kern_fstat(td, uap->fd, &ub); 1305 if (error == 0) { 1306 cvtstat(&ub, &oub); 1307 error = copyout(&oub, uap->sb, sizeof(oub)); 1308 } 1309 return (error); 1310 } 1311 #endif /* COMPAT_43 */ 1312 1313 /* 1314 * Return status information about a file descriptor. 1315 */ 1316 #ifndef _SYS_SYSPROTO_H_ 1317 struct fstat_args { 1318 int fd; 1319 struct stat *sb; 1320 }; 1321 #endif 1322 /* ARGSUSED */ 1323 int 1324 sys_fstat(struct thread *td, struct fstat_args *uap) 1325 { 1326 struct stat ub; 1327 int error; 1328 1329 error = kern_fstat(td, uap->fd, &ub); 1330 if (error == 0) 1331 error = copyout(&ub, uap->sb, sizeof(ub)); 1332 return (error); 1333 } 1334 1335 int 1336 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1337 { 1338 struct file *fp; 1339 int error; 1340 1341 AUDIT_ARG_FD(fd); 1342 1343 if ((error = fget(td, fd, CAP_FSTAT, &fp)) != 0) 1344 return (error); 1345 1346 AUDIT_ARG_FILE(td->td_proc, fp); 1347 1348 error = fo_stat(fp, sbp, td->td_ucred, td); 1349 fdrop(fp, td); 1350 #ifdef KTRACE 1351 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1352 ktrstat(sbp); 1353 #endif 1354 return (error); 1355 } 1356 1357 /* 1358 * Return status information about a file descriptor. 1359 */ 1360 #ifndef _SYS_SYSPROTO_H_ 1361 struct nfstat_args { 1362 int fd; 1363 struct nstat *sb; 1364 }; 1365 #endif 1366 /* ARGSUSED */ 1367 int 1368 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1369 { 1370 struct nstat nub; 1371 struct stat ub; 1372 int error; 1373 1374 error = kern_fstat(td, uap->fd, &ub); 1375 if (error == 0) { 1376 cvtnstat(&ub, &nub); 1377 error = copyout(&nub, uap->sb, sizeof(nub)); 1378 } 1379 return (error); 1380 } 1381 1382 /* 1383 * Return pathconf information about a file descriptor. 1384 */ 1385 #ifndef _SYS_SYSPROTO_H_ 1386 struct fpathconf_args { 1387 int fd; 1388 int name; 1389 }; 1390 #endif 1391 /* ARGSUSED */ 1392 int 1393 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1394 { 1395 struct file *fp; 1396 struct vnode *vp; 1397 int error; 1398 1399 if ((error = fget(td, uap->fd, CAP_FPATHCONF, &fp)) != 0) 1400 return (error); 1401 1402 /* If asynchronous I/O is available, it works for all descriptors. */ 1403 if (uap->name == _PC_ASYNC_IO) { 1404 td->td_retval[0] = async_io_version; 1405 goto out; 1406 } 1407 vp = fp->f_vnode; 1408 if (vp != NULL) { 1409 int vfslocked; 1410 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 1411 vn_lock(vp, LK_SHARED | LK_RETRY); 1412 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1413 VOP_UNLOCK(vp, 0); 1414 VFS_UNLOCK_GIANT(vfslocked); 1415 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1416 if (uap->name != _PC_PIPE_BUF) { 1417 error = EINVAL; 1418 } else { 1419 td->td_retval[0] = PIPE_BUF; 1420 error = 0; 1421 } 1422 } else { 1423 error = EOPNOTSUPP; 1424 } 1425 out: 1426 fdrop(fp, td); 1427 return (error); 1428 } 1429 1430 /* 1431 * Grow the file table to accomodate (at least) nfd descriptors. This may 1432 * block and drop the filedesc lock, but it will reacquire it before 1433 * returning. 1434 */ 1435 static void 1436 fdgrowtable(struct filedesc *fdp, int nfd) 1437 { 1438 struct filedesc0 *fdp0; 1439 struct freetable *fo; 1440 struct file **ntable; 1441 struct file **otable; 1442 char *nfileflags; 1443 int nnfiles, onfiles; 1444 NDSLOTTYPE *nmap; 1445 1446 FILEDESC_XLOCK_ASSERT(fdp); 1447 1448 KASSERT(fdp->fd_nfiles > 0, 1449 ("zero-length file table")); 1450 1451 /* compute the size of the new table */ 1452 onfiles = fdp->fd_nfiles; 1453 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1454 if (nnfiles <= onfiles) 1455 /* the table is already large enough */ 1456 return; 1457 1458 /* allocate a new table and (if required) new bitmaps */ 1459 FILEDESC_XUNLOCK(fdp); 1460 ntable = malloc((nnfiles * OFILESIZE) + sizeof(struct freetable), 1461 M_FILEDESC, M_ZERO | M_WAITOK); 1462 nfileflags = (char *)&ntable[nnfiles]; 1463 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) 1464 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, 1465 M_FILEDESC, M_ZERO | M_WAITOK); 1466 else 1467 nmap = NULL; 1468 FILEDESC_XLOCK(fdp); 1469 1470 /* 1471 * We now have new tables ready to go. Since we dropped the 1472 * filedesc lock to call malloc(), watch out for a race. 1473 */ 1474 onfiles = fdp->fd_nfiles; 1475 if (onfiles >= nnfiles) { 1476 /* we lost the race, but that's OK */ 1477 free(ntable, M_FILEDESC); 1478 if (nmap != NULL) 1479 free(nmap, M_FILEDESC); 1480 return; 1481 } 1482 bcopy(fdp->fd_ofiles, ntable, onfiles * sizeof(*ntable)); 1483 bcopy(fdp->fd_ofileflags, nfileflags, onfiles); 1484 otable = fdp->fd_ofiles; 1485 fdp->fd_ofileflags = nfileflags; 1486 fdp->fd_ofiles = ntable; 1487 /* 1488 * We must preserve ofiles until the process exits because we can't 1489 * be certain that no threads have references to the old table via 1490 * _fget(). 1491 */ 1492 if (onfiles > NDFILE) { 1493 fo = (struct freetable *)&otable[onfiles]; 1494 fdp0 = (struct filedesc0 *)fdp; 1495 fo->ft_table = otable; 1496 SLIST_INSERT_HEAD(&fdp0->fd_free, fo, ft_next); 1497 } 1498 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1499 bcopy(fdp->fd_map, nmap, NDSLOTS(onfiles) * sizeof(*nmap)); 1500 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1501 free(fdp->fd_map, M_FILEDESC); 1502 fdp->fd_map = nmap; 1503 } 1504 fdp->fd_nfiles = nnfiles; 1505 } 1506 1507 /* 1508 * Allocate a file descriptor for the process. 1509 */ 1510 int 1511 fdalloc(struct thread *td, int minfd, int *result) 1512 { 1513 struct proc *p = td->td_proc; 1514 struct filedesc *fdp = p->p_fd; 1515 int fd = -1, maxfd; 1516 #ifdef RACCT 1517 int error; 1518 #endif 1519 1520 FILEDESC_XLOCK_ASSERT(fdp); 1521 1522 if (fdp->fd_freefile > minfd) 1523 minfd = fdp->fd_freefile; 1524 1525 PROC_LOCK(p); 1526 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 1527 PROC_UNLOCK(p); 1528 1529 /* 1530 * Search the bitmap for a free descriptor. If none is found, try 1531 * to grow the file table. Keep at it until we either get a file 1532 * descriptor or run into process or system limits; fdgrowtable() 1533 * may drop the filedesc lock, so we're in a race. 1534 */ 1535 for (;;) { 1536 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1537 if (fd >= maxfd) 1538 return (EMFILE); 1539 if (fd < fdp->fd_nfiles) 1540 break; 1541 #ifdef RACCT 1542 PROC_LOCK(p); 1543 error = racct_set(p, RACCT_NOFILE, min(fdp->fd_nfiles * 2, maxfd)); 1544 PROC_UNLOCK(p); 1545 if (error != 0) 1546 return (EMFILE); 1547 #endif 1548 fdgrowtable(fdp, min(fdp->fd_nfiles * 2, maxfd)); 1549 } 1550 1551 /* 1552 * Perform some sanity checks, then mark the file descriptor as 1553 * used and return it to the caller. 1554 */ 1555 KASSERT(!fdisused(fdp, fd), 1556 ("fd_first_free() returned non-free descriptor")); 1557 KASSERT(fdp->fd_ofiles[fd] == NULL, 1558 ("free descriptor isn't")); 1559 fdp->fd_ofileflags[fd] = 0; /* XXX needed? */ 1560 fdused(fdp, fd); 1561 *result = fd; 1562 return (0); 1563 } 1564 1565 /* 1566 * Check to see whether n user file descriptors are available to the process 1567 * p. 1568 */ 1569 int 1570 fdavail(struct thread *td, int n) 1571 { 1572 struct proc *p = td->td_proc; 1573 struct filedesc *fdp = td->td_proc->p_fd; 1574 struct file **fpp; 1575 int i, lim, last; 1576 1577 FILEDESC_LOCK_ASSERT(fdp); 1578 1579 /* 1580 * XXX: This is only called from uipc_usrreq.c:unp_externalize(); 1581 * call racct_add() from there instead of dealing with containers 1582 * here. 1583 */ 1584 PROC_LOCK(p); 1585 lim = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 1586 PROC_UNLOCK(p); 1587 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) 1588 return (1); 1589 last = min(fdp->fd_nfiles, lim); 1590 fpp = &fdp->fd_ofiles[fdp->fd_freefile]; 1591 for (i = last - fdp->fd_freefile; --i >= 0; fpp++) { 1592 if (*fpp == NULL && --n <= 0) 1593 return (1); 1594 } 1595 return (0); 1596 } 1597 1598 /* 1599 * Create a new open file structure and allocate a file decriptor for the 1600 * process that refers to it. We add one reference to the file for the 1601 * descriptor table and one reference for resultfp. This is to prevent us 1602 * being preempted and the entry in the descriptor table closed after we 1603 * release the FILEDESC lock. 1604 */ 1605 int 1606 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1607 { 1608 struct file *fp; 1609 int error, fd; 1610 1611 error = falloc_noinstall(td, &fp); 1612 if (error) 1613 return (error); /* no reference held on error */ 1614 1615 error = finstall(td, fp, &fd, flags); 1616 if (error) { 1617 fdrop(fp, td); /* one reference (fp only) */ 1618 return (error); 1619 } 1620 1621 if (resultfp != NULL) 1622 *resultfp = fp; /* copy out result */ 1623 else 1624 fdrop(fp, td); /* release local reference */ 1625 1626 if (resultfd != NULL) 1627 *resultfd = fd; 1628 1629 return (0); 1630 } 1631 1632 /* 1633 * Create a new open file structure without allocating a file descriptor. 1634 */ 1635 int 1636 falloc_noinstall(struct thread *td, struct file **resultfp) 1637 { 1638 struct file *fp; 1639 int maxuserfiles = maxfiles - (maxfiles / 20); 1640 static struct timeval lastfail; 1641 static int curfail; 1642 1643 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1644 1645 if ((openfiles >= maxuserfiles && 1646 priv_check(td, PRIV_MAXFILES) != 0) || 1647 openfiles >= maxfiles) { 1648 if (ppsratecheck(&lastfail, &curfail, 1)) { 1649 printf("kern.maxfiles limit exceeded by uid %i, " 1650 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1651 } 1652 return (ENFILE); 1653 } 1654 atomic_add_int(&openfiles, 1); 1655 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1656 refcount_init(&fp->f_count, 1); 1657 fp->f_cred = crhold(td->td_ucred); 1658 fp->f_ops = &badfileops; 1659 fp->f_data = NULL; 1660 fp->f_vnode = NULL; 1661 *resultfp = fp; 1662 return (0); 1663 } 1664 1665 /* 1666 * Install a file in a file descriptor table. 1667 */ 1668 int 1669 finstall(struct thread *td, struct file *fp, int *fd, int flags) 1670 { 1671 struct filedesc *fdp = td->td_proc->p_fd; 1672 int error; 1673 1674 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1675 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1676 1677 FILEDESC_XLOCK(fdp); 1678 if ((error = fdalloc(td, 0, fd))) { 1679 FILEDESC_XUNLOCK(fdp); 1680 return (error); 1681 } 1682 fhold(fp); 1683 fdp->fd_ofiles[*fd] = fp; 1684 if ((flags & O_CLOEXEC) != 0) 1685 fdp->fd_ofileflags[*fd] |= UF_EXCLOSE; 1686 FILEDESC_XUNLOCK(fdp); 1687 return (0); 1688 } 1689 1690 /* 1691 * Build a new filedesc structure from another. 1692 * Copy the current, root, and jail root vnode references. 1693 */ 1694 struct filedesc * 1695 fdinit(struct filedesc *fdp) 1696 { 1697 struct filedesc0 *newfdp; 1698 1699 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1700 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1701 if (fdp != NULL) { 1702 FILEDESC_XLOCK(fdp); 1703 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1704 if (newfdp->fd_fd.fd_cdir) 1705 VREF(newfdp->fd_fd.fd_cdir); 1706 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1707 if (newfdp->fd_fd.fd_rdir) 1708 VREF(newfdp->fd_fd.fd_rdir); 1709 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1710 if (newfdp->fd_fd.fd_jdir) 1711 VREF(newfdp->fd_fd.fd_jdir); 1712 FILEDESC_XUNLOCK(fdp); 1713 } 1714 1715 /* Create the file descriptor table. */ 1716 newfdp->fd_fd.fd_refcnt = 1; 1717 newfdp->fd_fd.fd_holdcnt = 1; 1718 newfdp->fd_fd.fd_cmask = CMASK; 1719 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1720 newfdp->fd_fd.fd_ofileflags = newfdp->fd_dfileflags; 1721 newfdp->fd_fd.fd_nfiles = NDFILE; 1722 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1723 newfdp->fd_fd.fd_lastfile = -1; 1724 return (&newfdp->fd_fd); 1725 } 1726 1727 static struct filedesc * 1728 fdhold(struct proc *p) 1729 { 1730 struct filedesc *fdp; 1731 1732 mtx_lock(&fdesc_mtx); 1733 fdp = p->p_fd; 1734 if (fdp != NULL) 1735 fdp->fd_holdcnt++; 1736 mtx_unlock(&fdesc_mtx); 1737 return (fdp); 1738 } 1739 1740 static void 1741 fddrop(struct filedesc *fdp) 1742 { 1743 struct filedesc0 *fdp0; 1744 struct freetable *ft; 1745 int i; 1746 1747 mtx_lock(&fdesc_mtx); 1748 i = --fdp->fd_holdcnt; 1749 mtx_unlock(&fdesc_mtx); 1750 if (i > 0) 1751 return; 1752 1753 FILEDESC_LOCK_DESTROY(fdp); 1754 fdp0 = (struct filedesc0 *)fdp; 1755 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1756 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1757 free(ft->ft_table, M_FILEDESC); 1758 } 1759 free(fdp, M_FILEDESC); 1760 } 1761 1762 /* 1763 * Share a filedesc structure. 1764 */ 1765 struct filedesc * 1766 fdshare(struct filedesc *fdp) 1767 { 1768 1769 FILEDESC_XLOCK(fdp); 1770 fdp->fd_refcnt++; 1771 FILEDESC_XUNLOCK(fdp); 1772 return (fdp); 1773 } 1774 1775 /* 1776 * Unshare a filedesc structure, if necessary by making a copy 1777 */ 1778 void 1779 fdunshare(struct proc *p, struct thread *td) 1780 { 1781 1782 FILEDESC_XLOCK(p->p_fd); 1783 if (p->p_fd->fd_refcnt > 1) { 1784 struct filedesc *tmp; 1785 1786 FILEDESC_XUNLOCK(p->p_fd); 1787 tmp = fdcopy(p->p_fd); 1788 fdfree(td); 1789 p->p_fd = tmp; 1790 } else 1791 FILEDESC_XUNLOCK(p->p_fd); 1792 } 1793 1794 /* 1795 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1796 * this is to ease callers, not catch errors. 1797 */ 1798 struct filedesc * 1799 fdcopy(struct filedesc *fdp) 1800 { 1801 struct filedesc *newfdp; 1802 int i; 1803 1804 /* Certain daemons might not have file descriptors. */ 1805 if (fdp == NULL) 1806 return (NULL); 1807 1808 newfdp = fdinit(fdp); 1809 FILEDESC_SLOCK(fdp); 1810 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1811 FILEDESC_SUNLOCK(fdp); 1812 FILEDESC_XLOCK(newfdp); 1813 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1814 FILEDESC_XUNLOCK(newfdp); 1815 FILEDESC_SLOCK(fdp); 1816 } 1817 /* copy all passable descriptors (i.e. not kqueue) */ 1818 newfdp->fd_freefile = -1; 1819 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1820 if (fdisused(fdp, i) && 1821 (fdp->fd_ofiles[i]->f_ops->fo_flags & DFLAG_PASSABLE) && 1822 fdp->fd_ofiles[i]->f_ops != &badfileops) { 1823 newfdp->fd_ofiles[i] = fdp->fd_ofiles[i]; 1824 newfdp->fd_ofileflags[i] = fdp->fd_ofileflags[i]; 1825 fhold(newfdp->fd_ofiles[i]); 1826 newfdp->fd_lastfile = i; 1827 } else { 1828 if (newfdp->fd_freefile == -1) 1829 newfdp->fd_freefile = i; 1830 } 1831 } 1832 newfdp->fd_cmask = fdp->fd_cmask; 1833 FILEDESC_SUNLOCK(fdp); 1834 FILEDESC_XLOCK(newfdp); 1835 for (i = 0; i <= newfdp->fd_lastfile; ++i) 1836 if (newfdp->fd_ofiles[i] != NULL) 1837 fdused(newfdp, i); 1838 if (newfdp->fd_freefile == -1) 1839 newfdp->fd_freefile = i; 1840 FILEDESC_XUNLOCK(newfdp); 1841 return (newfdp); 1842 } 1843 1844 /* 1845 * Release a filedesc structure. 1846 */ 1847 void 1848 fdfree(struct thread *td) 1849 { 1850 struct filedesc *fdp; 1851 struct file **fpp; 1852 int i, locked; 1853 struct filedesc_to_leader *fdtol; 1854 struct file *fp; 1855 struct vnode *cdir, *jdir, *rdir, *vp; 1856 struct flock lf; 1857 1858 /* Certain daemons might not have file descriptors. */ 1859 fdp = td->td_proc->p_fd; 1860 if (fdp == NULL) 1861 return; 1862 1863 #ifdef RACCT 1864 PROC_LOCK(td->td_proc); 1865 racct_set(td->td_proc, RACCT_NOFILE, 0); 1866 PROC_UNLOCK(td->td_proc); 1867 #endif 1868 1869 /* Check for special need to clear POSIX style locks */ 1870 fdtol = td->td_proc->p_fdtol; 1871 if (fdtol != NULL) { 1872 FILEDESC_XLOCK(fdp); 1873 KASSERT(fdtol->fdl_refcount > 0, 1874 ("filedesc_to_refcount botch: fdl_refcount=%d", 1875 fdtol->fdl_refcount)); 1876 if (fdtol->fdl_refcount == 1 && 1877 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1878 for (i = 0, fpp = fdp->fd_ofiles; 1879 i <= fdp->fd_lastfile; 1880 i++, fpp++) { 1881 if (*fpp == NULL || 1882 (*fpp)->f_type != DTYPE_VNODE) 1883 continue; 1884 fp = *fpp; 1885 fhold(fp); 1886 FILEDESC_XUNLOCK(fdp); 1887 lf.l_whence = SEEK_SET; 1888 lf.l_start = 0; 1889 lf.l_len = 0; 1890 lf.l_type = F_UNLCK; 1891 vp = fp->f_vnode; 1892 locked = VFS_LOCK_GIANT(vp->v_mount); 1893 (void) VOP_ADVLOCK(vp, 1894 (caddr_t)td->td_proc-> 1895 p_leader, 1896 F_UNLCK, 1897 &lf, 1898 F_POSIX); 1899 VFS_UNLOCK_GIANT(locked); 1900 FILEDESC_XLOCK(fdp); 1901 fdrop(fp, td); 1902 fpp = fdp->fd_ofiles + i; 1903 } 1904 } 1905 retry: 1906 if (fdtol->fdl_refcount == 1) { 1907 if (fdp->fd_holdleaderscount > 0 && 1908 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1909 /* 1910 * close() or do_dup() has cleared a reference 1911 * in a shared file descriptor table. 1912 */ 1913 fdp->fd_holdleaderswakeup = 1; 1914 sx_sleep(&fdp->fd_holdleaderscount, 1915 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 1916 goto retry; 1917 } 1918 if (fdtol->fdl_holdcount > 0) { 1919 /* 1920 * Ensure that fdtol->fdl_leader remains 1921 * valid in closef(). 1922 */ 1923 fdtol->fdl_wakeup = 1; 1924 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 1925 "fdlhold", 0); 1926 goto retry; 1927 } 1928 } 1929 fdtol->fdl_refcount--; 1930 if (fdtol->fdl_refcount == 0 && 1931 fdtol->fdl_holdcount == 0) { 1932 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 1933 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 1934 } else 1935 fdtol = NULL; 1936 td->td_proc->p_fdtol = NULL; 1937 FILEDESC_XUNLOCK(fdp); 1938 if (fdtol != NULL) 1939 free(fdtol, M_FILEDESC_TO_LEADER); 1940 } 1941 FILEDESC_XLOCK(fdp); 1942 i = --fdp->fd_refcnt; 1943 FILEDESC_XUNLOCK(fdp); 1944 if (i > 0) 1945 return; 1946 1947 fpp = fdp->fd_ofiles; 1948 for (i = fdp->fd_lastfile; i-- >= 0; fpp++) { 1949 if (*fpp) { 1950 FILEDESC_XLOCK(fdp); 1951 fp = *fpp; 1952 *fpp = NULL; 1953 FILEDESC_XUNLOCK(fdp); 1954 (void) closef(fp, td); 1955 } 1956 } 1957 FILEDESC_XLOCK(fdp); 1958 1959 /* XXX This should happen earlier. */ 1960 mtx_lock(&fdesc_mtx); 1961 td->td_proc->p_fd = NULL; 1962 mtx_unlock(&fdesc_mtx); 1963 1964 if (fdp->fd_nfiles > NDFILE) 1965 free(fdp->fd_ofiles, M_FILEDESC); 1966 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 1967 free(fdp->fd_map, M_FILEDESC); 1968 1969 fdp->fd_nfiles = 0; 1970 1971 cdir = fdp->fd_cdir; 1972 fdp->fd_cdir = NULL; 1973 rdir = fdp->fd_rdir; 1974 fdp->fd_rdir = NULL; 1975 jdir = fdp->fd_jdir; 1976 fdp->fd_jdir = NULL; 1977 FILEDESC_XUNLOCK(fdp); 1978 1979 if (cdir) { 1980 locked = VFS_LOCK_GIANT(cdir->v_mount); 1981 vrele(cdir); 1982 VFS_UNLOCK_GIANT(locked); 1983 } 1984 if (rdir) { 1985 locked = VFS_LOCK_GIANT(rdir->v_mount); 1986 vrele(rdir); 1987 VFS_UNLOCK_GIANT(locked); 1988 } 1989 if (jdir) { 1990 locked = VFS_LOCK_GIANT(jdir->v_mount); 1991 vrele(jdir); 1992 VFS_UNLOCK_GIANT(locked); 1993 } 1994 1995 fddrop(fdp); 1996 } 1997 1998 /* 1999 * For setugid programs, we don't want to people to use that setugidness 2000 * to generate error messages which write to a file which otherwise would 2001 * otherwise be off-limits to the process. We check for filesystems where 2002 * the vnode can change out from under us after execve (like [lin]procfs). 2003 * 2004 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2005 * sufficient. We also don't check for setugidness since we know we are. 2006 */ 2007 static int 2008 is_unsafe(struct file *fp) 2009 { 2010 if (fp->f_type == DTYPE_VNODE) { 2011 struct vnode *vp = fp->f_vnode; 2012 2013 if ((vp->v_vflag & VV_PROCDEP) != 0) 2014 return (1); 2015 } 2016 return (0); 2017 } 2018 2019 /* 2020 * Make this setguid thing safe, if at all possible. 2021 */ 2022 void 2023 setugidsafety(struct thread *td) 2024 { 2025 struct filedesc *fdp; 2026 int i; 2027 2028 /* Certain daemons might not have file descriptors. */ 2029 fdp = td->td_proc->p_fd; 2030 if (fdp == NULL) 2031 return; 2032 2033 /* 2034 * Note: fdp->fd_ofiles may be reallocated out from under us while 2035 * we are blocked in a close. Be careful! 2036 */ 2037 FILEDESC_XLOCK(fdp); 2038 for (i = 0; i <= fdp->fd_lastfile; i++) { 2039 if (i > 2) 2040 break; 2041 if (fdp->fd_ofiles[i] && is_unsafe(fdp->fd_ofiles[i])) { 2042 struct file *fp; 2043 2044 knote_fdclose(td, i); 2045 /* 2046 * NULL-out descriptor prior to close to avoid 2047 * a race while close blocks. 2048 */ 2049 fp = fdp->fd_ofiles[i]; 2050 fdp->fd_ofiles[i] = NULL; 2051 fdp->fd_ofileflags[i] = 0; 2052 fdunused(fdp, i); 2053 FILEDESC_XUNLOCK(fdp); 2054 (void) closef(fp, td); 2055 FILEDESC_XLOCK(fdp); 2056 } 2057 } 2058 FILEDESC_XUNLOCK(fdp); 2059 } 2060 2061 /* 2062 * If a specific file object occupies a specific file descriptor, close the 2063 * file descriptor entry and drop a reference on the file object. This is a 2064 * convenience function to handle a subsequent error in a function that calls 2065 * falloc() that handles the race that another thread might have closed the 2066 * file descriptor out from under the thread creating the file object. 2067 */ 2068 void 2069 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2070 { 2071 2072 FILEDESC_XLOCK(fdp); 2073 if (fdp->fd_ofiles[idx] == fp) { 2074 fdp->fd_ofiles[idx] = NULL; 2075 fdunused(fdp, idx); 2076 FILEDESC_XUNLOCK(fdp); 2077 fdrop(fp, td); 2078 } else 2079 FILEDESC_XUNLOCK(fdp); 2080 } 2081 2082 /* 2083 * Close any files on exec? 2084 */ 2085 void 2086 fdcloseexec(struct thread *td) 2087 { 2088 struct filedesc *fdp; 2089 int i; 2090 2091 /* Certain daemons might not have file descriptors. */ 2092 fdp = td->td_proc->p_fd; 2093 if (fdp == NULL) 2094 return; 2095 2096 FILEDESC_XLOCK(fdp); 2097 2098 /* 2099 * We cannot cache fd_ofiles or fd_ofileflags since operations 2100 * may block and rip them out from under us. 2101 */ 2102 for (i = 0; i <= fdp->fd_lastfile; i++) { 2103 if (fdp->fd_ofiles[i] != NULL && 2104 (fdp->fd_ofiles[i]->f_type == DTYPE_MQUEUE || 2105 (fdp->fd_ofileflags[i] & UF_EXCLOSE))) { 2106 struct file *fp; 2107 2108 knote_fdclose(td, i); 2109 /* 2110 * NULL-out descriptor prior to close to avoid 2111 * a race while close blocks. 2112 */ 2113 fp = fdp->fd_ofiles[i]; 2114 fdp->fd_ofiles[i] = NULL; 2115 fdp->fd_ofileflags[i] = 0; 2116 fdunused(fdp, i); 2117 if (fp->f_type == DTYPE_MQUEUE) 2118 mq_fdclose(td, i, fp); 2119 FILEDESC_XUNLOCK(fdp); 2120 (void) closef(fp, td); 2121 FILEDESC_XLOCK(fdp); 2122 } 2123 } 2124 FILEDESC_XUNLOCK(fdp); 2125 } 2126 2127 /* 2128 * It is unsafe for set[ug]id processes to be started with file 2129 * descriptors 0..2 closed, as these descriptors are given implicit 2130 * significance in the Standard C library. fdcheckstd() will create a 2131 * descriptor referencing /dev/null for each of stdin, stdout, and 2132 * stderr that is not already open. 2133 */ 2134 int 2135 fdcheckstd(struct thread *td) 2136 { 2137 struct filedesc *fdp; 2138 register_t retval, save; 2139 int i, error, devnull; 2140 2141 fdp = td->td_proc->p_fd; 2142 if (fdp == NULL) 2143 return (0); 2144 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2145 devnull = -1; 2146 error = 0; 2147 for (i = 0; i < 3; i++) { 2148 if (fdp->fd_ofiles[i] != NULL) 2149 continue; 2150 if (devnull < 0) { 2151 save = td->td_retval[0]; 2152 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2153 O_RDWR, 0); 2154 devnull = td->td_retval[0]; 2155 td->td_retval[0] = save; 2156 if (error) 2157 break; 2158 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2159 } else { 2160 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2161 if (error != 0) 2162 break; 2163 } 2164 } 2165 return (error); 2166 } 2167 2168 /* 2169 * Internal form of close. Decrement reference count on file structure. 2170 * Note: td may be NULL when closing a file that was being passed in a 2171 * message. 2172 * 2173 * XXXRW: Giant is not required for the caller, but often will be held; this 2174 * makes it moderately likely the Giant will be recursed in the VFS case. 2175 */ 2176 int 2177 closef(struct file *fp, struct thread *td) 2178 { 2179 struct vnode *vp; 2180 struct flock lf; 2181 struct filedesc_to_leader *fdtol; 2182 struct filedesc *fdp; 2183 struct file *fp_object; 2184 2185 /* 2186 * POSIX record locking dictates that any close releases ALL 2187 * locks owned by this process. This is handled by setting 2188 * a flag in the unlock to free ONLY locks obeying POSIX 2189 * semantics, and not to free BSD-style file locks. 2190 * If the descriptor was in a message, POSIX-style locks 2191 * aren't passed with the descriptor, and the thread pointer 2192 * will be NULL. Callers should be careful only to pass a 2193 * NULL thread pointer when there really is no owning 2194 * context that might have locks, or the locks will be 2195 * leaked. 2196 * 2197 * If this is a capability, we do lock processing under the underlying 2198 * node, not the capability itself. 2199 */ 2200 (void)cap_funwrap(fp, 0, &fp_object); 2201 if ((fp_object->f_type == DTYPE_VNODE) && (td != NULL)) { 2202 int vfslocked; 2203 2204 vp = fp_object->f_vnode; 2205 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 2206 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2207 lf.l_whence = SEEK_SET; 2208 lf.l_start = 0; 2209 lf.l_len = 0; 2210 lf.l_type = F_UNLCK; 2211 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2212 F_UNLCK, &lf, F_POSIX); 2213 } 2214 fdtol = td->td_proc->p_fdtol; 2215 if (fdtol != NULL) { 2216 /* 2217 * Handle special case where file descriptor table is 2218 * shared between multiple process leaders. 2219 */ 2220 fdp = td->td_proc->p_fd; 2221 FILEDESC_XLOCK(fdp); 2222 for (fdtol = fdtol->fdl_next; 2223 fdtol != td->td_proc->p_fdtol; 2224 fdtol = fdtol->fdl_next) { 2225 if ((fdtol->fdl_leader->p_flag & 2226 P_ADVLOCK) == 0) 2227 continue; 2228 fdtol->fdl_holdcount++; 2229 FILEDESC_XUNLOCK(fdp); 2230 lf.l_whence = SEEK_SET; 2231 lf.l_start = 0; 2232 lf.l_len = 0; 2233 lf.l_type = F_UNLCK; 2234 vp = fp_object->f_vnode; 2235 (void) VOP_ADVLOCK(vp, 2236 (caddr_t)fdtol->fdl_leader, 2237 F_UNLCK, &lf, F_POSIX); 2238 FILEDESC_XLOCK(fdp); 2239 fdtol->fdl_holdcount--; 2240 if (fdtol->fdl_holdcount == 0 && 2241 fdtol->fdl_wakeup != 0) { 2242 fdtol->fdl_wakeup = 0; 2243 wakeup(fdtol); 2244 } 2245 } 2246 FILEDESC_XUNLOCK(fdp); 2247 } 2248 VFS_UNLOCK_GIANT(vfslocked); 2249 } 2250 return (fdrop(fp, td)); 2251 } 2252 2253 /* 2254 * Initialize the file pointer with the specified properties. 2255 * 2256 * The ops are set with release semantics to be certain that the flags, type, 2257 * and data are visible when ops is. This is to prevent ops methods from being 2258 * called with bad data. 2259 */ 2260 void 2261 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2262 { 2263 fp->f_data = data; 2264 fp->f_flag = flag; 2265 fp->f_type = type; 2266 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2267 } 2268 2269 struct file * 2270 fget_unlocked(struct filedesc *fdp, int fd) 2271 { 2272 struct file *fp; 2273 u_int count; 2274 2275 if (fd < 0 || fd >= fdp->fd_nfiles) 2276 return (NULL); 2277 /* 2278 * Fetch the descriptor locklessly. We avoid fdrop() races by 2279 * never raising a refcount above 0. To accomplish this we have 2280 * to use a cmpset loop rather than an atomic_add. The descriptor 2281 * must be re-verified once we acquire a reference to be certain 2282 * that the identity is still correct and we did not lose a race 2283 * due to preemption. 2284 */ 2285 for (;;) { 2286 fp = fdp->fd_ofiles[fd]; 2287 if (fp == NULL) 2288 break; 2289 count = fp->f_count; 2290 if (count == 0) 2291 continue; 2292 /* 2293 * Use an acquire barrier to prevent caching of fd_ofiles 2294 * so it is refreshed for verification. 2295 */ 2296 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2297 continue; 2298 if (fp == fdp->fd_ofiles[fd]) 2299 break; 2300 fdrop(fp, curthread); 2301 } 2302 2303 return (fp); 2304 } 2305 2306 /* 2307 * Extract the file pointer associated with the specified descriptor for the 2308 * current user process. 2309 * 2310 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2311 * returned. 2312 * 2313 * If the FGET_GETCAP flag is set, the capability itself will be returned. 2314 * Calling _fget() with FGET_GETCAP on a non-capability will return EINVAL. 2315 * Otherwise, if the file is a capability, its rights will be checked against 2316 * the capability rights mask, and if successful, the object will be unwrapped. 2317 * 2318 * If an error occured the non-zero error is returned and *fpp is set to 2319 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2320 * responsible for fdrop(). 2321 */ 2322 #define FGET_GETCAP 0x00000001 2323 static __inline int 2324 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2325 cap_rights_t needrights, cap_rights_t *haverightsp, u_char *maxprotp, 2326 int fget_flags) 2327 { 2328 struct filedesc *fdp; 2329 struct file *fp; 2330 #ifdef CAPABILITIES 2331 struct file *fp_fromcap; 2332 int error; 2333 #endif 2334 2335 *fpp = NULL; 2336 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2337 return (EBADF); 2338 if ((fp = fget_unlocked(fdp, fd)) == NULL) 2339 return (EBADF); 2340 if (fp->f_ops == &badfileops) { 2341 fdrop(fp, td); 2342 return (EBADF); 2343 } 2344 2345 #ifdef CAPABILITIES 2346 /* 2347 * If this is a capability, what rights does it have? 2348 */ 2349 if (haverightsp != NULL) { 2350 if (fp->f_type == DTYPE_CAPABILITY) 2351 *haverightsp = cap_rights(fp); 2352 else 2353 *haverightsp = CAP_MASK_VALID; 2354 } 2355 2356 /* 2357 * If a capability has been requested, return the capability directly. 2358 * Otherwise, check capability rights, extract the underlying object, 2359 * and check its access flags. 2360 */ 2361 if (fget_flags & FGET_GETCAP) { 2362 if (fp->f_type != DTYPE_CAPABILITY) { 2363 fdrop(fp, td); 2364 return (EINVAL); 2365 } 2366 } else { 2367 if (maxprotp == NULL) 2368 error = cap_funwrap(fp, needrights, &fp_fromcap); 2369 else 2370 error = cap_funwrap_mmap(fp, needrights, maxprotp, 2371 &fp_fromcap); 2372 if (error) { 2373 fdrop(fp, td); 2374 return (error); 2375 } 2376 2377 /* 2378 * If we've unwrapped a file, drop the original capability 2379 * and hold the new descriptor. fp after this point refers to 2380 * the actual (unwrapped) object, not the capability. 2381 */ 2382 if (fp != fp_fromcap) { 2383 fhold(fp_fromcap); 2384 fdrop(fp, td); 2385 fp = fp_fromcap; 2386 } 2387 } 2388 #else /* !CAPABILITIES */ 2389 KASSERT(fp->f_type != DTYPE_CAPABILITY, 2390 ("%s: saw capability", __func__)); 2391 if (maxprotp != NULL) 2392 *maxprotp = VM_PROT_ALL; 2393 #endif /* CAPABILITIES */ 2394 2395 /* 2396 * FREAD and FWRITE failure return EBADF as per POSIX. 2397 * 2398 * Only one flag, or 0, may be specified. 2399 */ 2400 if ((flags == FREAD && (fp->f_flag & FREAD) == 0) || 2401 (flags == FWRITE && (fp->f_flag & FWRITE) == 0)) { 2402 fdrop(fp, td); 2403 return (EBADF); 2404 } 2405 *fpp = fp; 2406 return (0); 2407 } 2408 2409 int 2410 fget(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) 2411 { 2412 2413 return(_fget(td, fd, fpp, 0, rights, NULL, NULL, 0)); 2414 } 2415 2416 int 2417 fget_mmap(struct thread *td, int fd, cap_rights_t rights, u_char *maxprotp, 2418 struct file **fpp) 2419 { 2420 2421 return (_fget(td, fd, fpp, 0, rights, NULL, maxprotp, 0)); 2422 } 2423 2424 int 2425 fget_read(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) 2426 { 2427 2428 return(_fget(td, fd, fpp, FREAD, rights, NULL, NULL, 0)); 2429 } 2430 2431 int 2432 fget_write(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) 2433 { 2434 2435 return (_fget(td, fd, fpp, FWRITE, rights, NULL, NULL, 0)); 2436 } 2437 2438 /* 2439 * Unlike the other fget() calls, which accept and check capability rights 2440 * but never return capabilities, fgetcap() returns the capability but doesn't 2441 * check capability rights. 2442 */ 2443 int 2444 fgetcap(struct thread *td, int fd, struct file **fpp) 2445 { 2446 2447 return (_fget(td, fd, fpp, 0, 0, NULL, NULL, FGET_GETCAP)); 2448 } 2449 2450 2451 /* 2452 * Like fget() but loads the underlying vnode, or returns an error if the 2453 * descriptor does not represent a vnode. Note that pipes use vnodes but 2454 * never have VM objects. The returned vnode will be vref()'d. 2455 * 2456 * XXX: what about the unused flags ? 2457 */ 2458 static __inline int 2459 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t needrights, 2460 cap_rights_t *haverightsp, struct vnode **vpp) 2461 { 2462 struct file *fp; 2463 int error; 2464 2465 *vpp = NULL; 2466 if ((error = _fget(td, fd, &fp, flags, needrights, haverightsp, 2467 NULL, 0)) != 0) 2468 return (error); 2469 if (fp->f_vnode == NULL) { 2470 error = EINVAL; 2471 } else { 2472 *vpp = fp->f_vnode; 2473 vref(*vpp); 2474 } 2475 fdrop(fp, td); 2476 2477 return (error); 2478 } 2479 2480 int 2481 fgetvp(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) 2482 { 2483 2484 return (_fgetvp(td, fd, 0, rights, NULL, vpp)); 2485 } 2486 2487 int 2488 fgetvp_rights(struct thread *td, int fd, cap_rights_t need, cap_rights_t *have, 2489 struct vnode **vpp) 2490 { 2491 return (_fgetvp(td, fd, 0, need, have, vpp)); 2492 } 2493 2494 int 2495 fgetvp_read(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) 2496 { 2497 2498 return (_fgetvp(td, fd, FREAD, rights, NULL, vpp)); 2499 } 2500 2501 #ifdef notyet 2502 int 2503 fgetvp_write(struct thread *td, int fd, cap_rights_t rights, 2504 struct vnode **vpp) 2505 { 2506 2507 return (_fgetvp(td, fd, FWRITE, rights, NULL, vpp)); 2508 } 2509 #endif 2510 2511 /* 2512 * Like fget() but loads the underlying socket, or returns an error if the 2513 * descriptor does not represent a socket. 2514 * 2515 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2516 * in the future. 2517 * 2518 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2519 * on their file descriptor reference to prevent the socket from being free'd 2520 * during use. 2521 */ 2522 int 2523 fgetsock(struct thread *td, int fd, cap_rights_t rights, struct socket **spp, 2524 u_int *fflagp) 2525 { 2526 struct file *fp; 2527 int error; 2528 2529 *spp = NULL; 2530 if (fflagp != NULL) 2531 *fflagp = 0; 2532 if ((error = _fget(td, fd, &fp, 0, rights, NULL, NULL, 0)) != 0) 2533 return (error); 2534 if (fp->f_type != DTYPE_SOCKET) { 2535 error = ENOTSOCK; 2536 } else { 2537 *spp = fp->f_data; 2538 if (fflagp) 2539 *fflagp = fp->f_flag; 2540 SOCK_LOCK(*spp); 2541 soref(*spp); 2542 SOCK_UNLOCK(*spp); 2543 } 2544 fdrop(fp, td); 2545 2546 return (error); 2547 } 2548 2549 /* 2550 * Drop the reference count on the socket and XXX release the SX lock in the 2551 * future. The last reference closes the socket. 2552 * 2553 * Note: fputsock() is deprecated, see comment for fgetsock(). 2554 */ 2555 void 2556 fputsock(struct socket *so) 2557 { 2558 2559 ACCEPT_LOCK(); 2560 SOCK_LOCK(so); 2561 CURVNET_SET(so->so_vnet); 2562 sorele(so); 2563 CURVNET_RESTORE(); 2564 } 2565 2566 /* 2567 * Handle the last reference to a file being closed. 2568 * 2569 * No special capability handling here, as the capability's fo_close will run 2570 * instead of the object here, and perform any necessary drop on the object. 2571 */ 2572 int 2573 _fdrop(struct file *fp, struct thread *td) 2574 { 2575 int error; 2576 2577 error = 0; 2578 if (fp->f_count != 0) 2579 panic("fdrop: count %d", fp->f_count); 2580 if (fp->f_ops != &badfileops) 2581 error = fo_close(fp, td); 2582 atomic_subtract_int(&openfiles, 1); 2583 crfree(fp->f_cred); 2584 free(fp->f_advice, M_FADVISE); 2585 uma_zfree(file_zone, fp); 2586 2587 return (error); 2588 } 2589 2590 /* 2591 * Apply an advisory lock on a file descriptor. 2592 * 2593 * Just attempt to get a record lock of the requested type on the entire file 2594 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2595 */ 2596 #ifndef _SYS_SYSPROTO_H_ 2597 struct flock_args { 2598 int fd; 2599 int how; 2600 }; 2601 #endif 2602 /* ARGSUSED */ 2603 int 2604 sys_flock(struct thread *td, struct flock_args *uap) 2605 { 2606 struct file *fp; 2607 struct vnode *vp; 2608 struct flock lf; 2609 int vfslocked; 2610 int error; 2611 2612 if ((error = fget(td, uap->fd, CAP_FLOCK, &fp)) != 0) 2613 return (error); 2614 if (fp->f_type != DTYPE_VNODE) { 2615 fdrop(fp, td); 2616 return (EOPNOTSUPP); 2617 } 2618 2619 vp = fp->f_vnode; 2620 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 2621 lf.l_whence = SEEK_SET; 2622 lf.l_start = 0; 2623 lf.l_len = 0; 2624 if (uap->how & LOCK_UN) { 2625 lf.l_type = F_UNLCK; 2626 atomic_clear_int(&fp->f_flag, FHASLOCK); 2627 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2628 goto done2; 2629 } 2630 if (uap->how & LOCK_EX) 2631 lf.l_type = F_WRLCK; 2632 else if (uap->how & LOCK_SH) 2633 lf.l_type = F_RDLCK; 2634 else { 2635 error = EBADF; 2636 goto done2; 2637 } 2638 atomic_set_int(&fp->f_flag, FHASLOCK); 2639 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2640 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2641 done2: 2642 fdrop(fp, td); 2643 VFS_UNLOCK_GIANT(vfslocked); 2644 return (error); 2645 } 2646 /* 2647 * Duplicate the specified descriptor to a free descriptor. 2648 */ 2649 int 2650 dupfdopen(struct thread *td, struct filedesc *fdp, int indx, int dfd, int mode, int error) 2651 { 2652 struct file *wfp; 2653 struct file *fp; 2654 2655 /* 2656 * If the to-be-dup'd fd number is greater than the allowed number 2657 * of file descriptors, or the fd to be dup'd has already been 2658 * closed, then reject. 2659 */ 2660 FILEDESC_XLOCK(fdp); 2661 if (dfd < 0 || dfd >= fdp->fd_nfiles || 2662 (wfp = fdp->fd_ofiles[dfd]) == NULL) { 2663 FILEDESC_XUNLOCK(fdp); 2664 return (EBADF); 2665 } 2666 2667 /* 2668 * There are two cases of interest here. 2669 * 2670 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2671 * 2672 * For ENXIO steal away the file structure from (dfd) and store it in 2673 * (indx). (dfd) is effectively closed by this operation. 2674 * 2675 * Any other error code is just returned. 2676 */ 2677 switch (error) { 2678 case ENODEV: 2679 /* 2680 * Check that the mode the file is being opened for is a 2681 * subset of the mode of the existing descriptor. 2682 */ 2683 if (((mode & (FREAD|FWRITE)) | wfp->f_flag) != wfp->f_flag) { 2684 FILEDESC_XUNLOCK(fdp); 2685 return (EACCES); 2686 } 2687 fp = fdp->fd_ofiles[indx]; 2688 fdp->fd_ofiles[indx] = wfp; 2689 fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd]; 2690 if (fp == NULL) 2691 fdused(fdp, indx); 2692 fhold(wfp); 2693 FILEDESC_XUNLOCK(fdp); 2694 if (fp != NULL) 2695 /* 2696 * We now own the reference to fp that the ofiles[] 2697 * array used to own. Release it. 2698 */ 2699 fdrop(fp, td); 2700 return (0); 2701 2702 case ENXIO: 2703 /* 2704 * Steal away the file pointer from dfd and stuff it into indx. 2705 */ 2706 fp = fdp->fd_ofiles[indx]; 2707 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2708 fdp->fd_ofiles[dfd] = NULL; 2709 fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd]; 2710 fdp->fd_ofileflags[dfd] = 0; 2711 fdunused(fdp, dfd); 2712 if (fp == NULL) 2713 fdused(fdp, indx); 2714 FILEDESC_XUNLOCK(fdp); 2715 2716 /* 2717 * We now own the reference to fp that the ofiles[] array 2718 * used to own. Release it. 2719 */ 2720 if (fp != NULL) 2721 fdrop(fp, td); 2722 return (0); 2723 2724 default: 2725 FILEDESC_XUNLOCK(fdp); 2726 return (error); 2727 } 2728 /* NOTREACHED */ 2729 } 2730 2731 /* 2732 * Scan all active processes and prisons to see if any of them have a current 2733 * or root directory of `olddp'. If so, replace them with the new mount point. 2734 */ 2735 void 2736 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2737 { 2738 struct filedesc *fdp; 2739 struct prison *pr; 2740 struct proc *p; 2741 int nrele; 2742 2743 if (vrefcnt(olddp) == 1) 2744 return; 2745 nrele = 0; 2746 sx_slock(&allproc_lock); 2747 FOREACH_PROC_IN_SYSTEM(p) { 2748 fdp = fdhold(p); 2749 if (fdp == NULL) 2750 continue; 2751 FILEDESC_XLOCK(fdp); 2752 if (fdp->fd_cdir == olddp) { 2753 vref(newdp); 2754 fdp->fd_cdir = newdp; 2755 nrele++; 2756 } 2757 if (fdp->fd_rdir == olddp) { 2758 vref(newdp); 2759 fdp->fd_rdir = newdp; 2760 nrele++; 2761 } 2762 if (fdp->fd_jdir == olddp) { 2763 vref(newdp); 2764 fdp->fd_jdir = newdp; 2765 nrele++; 2766 } 2767 FILEDESC_XUNLOCK(fdp); 2768 fddrop(fdp); 2769 } 2770 sx_sunlock(&allproc_lock); 2771 if (rootvnode == olddp) { 2772 vref(newdp); 2773 rootvnode = newdp; 2774 nrele++; 2775 } 2776 mtx_lock(&prison0.pr_mtx); 2777 if (prison0.pr_root == olddp) { 2778 vref(newdp); 2779 prison0.pr_root = newdp; 2780 nrele++; 2781 } 2782 mtx_unlock(&prison0.pr_mtx); 2783 sx_slock(&allprison_lock); 2784 TAILQ_FOREACH(pr, &allprison, pr_list) { 2785 mtx_lock(&pr->pr_mtx); 2786 if (pr->pr_root == olddp) { 2787 vref(newdp); 2788 pr->pr_root = newdp; 2789 nrele++; 2790 } 2791 mtx_unlock(&pr->pr_mtx); 2792 } 2793 sx_sunlock(&allprison_lock); 2794 while (nrele--) 2795 vrele(olddp); 2796 } 2797 2798 struct filedesc_to_leader * 2799 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2800 { 2801 struct filedesc_to_leader *fdtol; 2802 2803 fdtol = malloc(sizeof(struct filedesc_to_leader), 2804 M_FILEDESC_TO_LEADER, 2805 M_WAITOK); 2806 fdtol->fdl_refcount = 1; 2807 fdtol->fdl_holdcount = 0; 2808 fdtol->fdl_wakeup = 0; 2809 fdtol->fdl_leader = leader; 2810 if (old != NULL) { 2811 FILEDESC_XLOCK(fdp); 2812 fdtol->fdl_next = old->fdl_next; 2813 fdtol->fdl_prev = old; 2814 old->fdl_next = fdtol; 2815 fdtol->fdl_next->fdl_prev = fdtol; 2816 FILEDESC_XUNLOCK(fdp); 2817 } else { 2818 fdtol->fdl_next = fdtol; 2819 fdtol->fdl_prev = fdtol; 2820 } 2821 return (fdtol); 2822 } 2823 2824 /* 2825 * Get file structures globally. 2826 */ 2827 static int 2828 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2829 { 2830 struct xfile xf; 2831 struct filedesc *fdp; 2832 struct file *fp; 2833 struct proc *p; 2834 int error, n; 2835 2836 error = sysctl_wire_old_buffer(req, 0); 2837 if (error != 0) 2838 return (error); 2839 if (req->oldptr == NULL) { 2840 n = 0; 2841 sx_slock(&allproc_lock); 2842 FOREACH_PROC_IN_SYSTEM(p) { 2843 if (p->p_state == PRS_NEW) 2844 continue; 2845 fdp = fdhold(p); 2846 if (fdp == NULL) 2847 continue; 2848 /* overestimates sparse tables. */ 2849 if (fdp->fd_lastfile > 0) 2850 n += fdp->fd_lastfile; 2851 fddrop(fdp); 2852 } 2853 sx_sunlock(&allproc_lock); 2854 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2855 } 2856 error = 0; 2857 bzero(&xf, sizeof(xf)); 2858 xf.xf_size = sizeof(xf); 2859 sx_slock(&allproc_lock); 2860 FOREACH_PROC_IN_SYSTEM(p) { 2861 PROC_LOCK(p); 2862 if (p->p_state == PRS_NEW) { 2863 PROC_UNLOCK(p); 2864 continue; 2865 } 2866 if (p_cansee(req->td, p) != 0) { 2867 PROC_UNLOCK(p); 2868 continue; 2869 } 2870 xf.xf_pid = p->p_pid; 2871 xf.xf_uid = p->p_ucred->cr_uid; 2872 PROC_UNLOCK(p); 2873 fdp = fdhold(p); 2874 if (fdp == NULL) 2875 continue; 2876 FILEDESC_SLOCK(fdp); 2877 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) { 2878 if ((fp = fdp->fd_ofiles[n]) == NULL) 2879 continue; 2880 xf.xf_fd = n; 2881 xf.xf_file = fp; 2882 xf.xf_data = fp->f_data; 2883 xf.xf_vnode = fp->f_vnode; 2884 xf.xf_type = fp->f_type; 2885 xf.xf_count = fp->f_count; 2886 xf.xf_msgcount = 0; 2887 xf.xf_offset = fp->f_offset; 2888 xf.xf_flag = fp->f_flag; 2889 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2890 if (error) 2891 break; 2892 } 2893 FILEDESC_SUNLOCK(fdp); 2894 fddrop(fdp); 2895 if (error) 2896 break; 2897 } 2898 sx_sunlock(&allproc_lock); 2899 return (error); 2900 } 2901 2902 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD, 2903 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2904 2905 #ifdef KINFO_OFILE_SIZE 2906 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 2907 #endif 2908 2909 #ifdef COMPAT_FREEBSD7 2910 static int 2911 export_vnode_for_osysctl(struct vnode *vp, int type, 2912 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 2913 { 2914 int error; 2915 char *fullpath, *freepath; 2916 int vfslocked; 2917 2918 bzero(kif, sizeof(*kif)); 2919 kif->kf_structsize = sizeof(*kif); 2920 2921 vref(vp); 2922 kif->kf_fd = type; 2923 kif->kf_type = KF_TYPE_VNODE; 2924 /* This function only handles directories. */ 2925 if (vp->v_type != VDIR) { 2926 vrele(vp); 2927 return (ENOTDIR); 2928 } 2929 kif->kf_vnode_type = KF_VTYPE_VDIR; 2930 2931 /* 2932 * This is not a true file descriptor, so we set a bogus refcount 2933 * and offset to indicate these fields should be ignored. 2934 */ 2935 kif->kf_ref_count = -1; 2936 kif->kf_offset = -1; 2937 2938 freepath = NULL; 2939 fullpath = "-"; 2940 FILEDESC_SUNLOCK(fdp); 2941 vn_fullpath(curthread, vp, &fullpath, &freepath); 2942 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 2943 vrele(vp); 2944 VFS_UNLOCK_GIANT(vfslocked); 2945 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 2946 if (freepath != NULL) 2947 free(freepath, M_TEMP); 2948 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 2949 FILEDESC_SLOCK(fdp); 2950 return (error); 2951 } 2952 2953 /* 2954 * Get per-process file descriptors for use by procstat(1), et al. 2955 */ 2956 static int 2957 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 2958 { 2959 char *fullpath, *freepath; 2960 struct kinfo_ofile *kif; 2961 struct filedesc *fdp; 2962 int error, i, *name; 2963 struct shmfd *shmfd; 2964 struct socket *so; 2965 struct vnode *vp; 2966 struct file *fp; 2967 struct proc *p; 2968 struct tty *tp; 2969 int vfslocked; 2970 2971 name = (int *)arg1; 2972 if ((p = pfind((pid_t)name[0])) == NULL) 2973 return (ESRCH); 2974 if ((error = p_candebug(curthread, p))) { 2975 PROC_UNLOCK(p); 2976 return (error); 2977 } 2978 fdp = fdhold(p); 2979 PROC_UNLOCK(p); 2980 if (fdp == NULL) 2981 return (ENOENT); 2982 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 2983 FILEDESC_SLOCK(fdp); 2984 if (fdp->fd_cdir != NULL) 2985 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 2986 fdp, req); 2987 if (fdp->fd_rdir != NULL) 2988 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 2989 fdp, req); 2990 if (fdp->fd_jdir != NULL) 2991 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 2992 fdp, req); 2993 for (i = 0; i < fdp->fd_nfiles; i++) { 2994 if ((fp = fdp->fd_ofiles[i]) == NULL) 2995 continue; 2996 bzero(kif, sizeof(*kif)); 2997 kif->kf_structsize = sizeof(*kif); 2998 vp = NULL; 2999 so = NULL; 3000 tp = NULL; 3001 shmfd = NULL; 3002 kif->kf_fd = i; 3003 3004 #ifdef CAPABILITIES 3005 /* 3006 * When reporting a capability, most fields will be from the 3007 * underlying object, but do mark as a capability. With 3008 * ofiledesc, we don't have a field to export the cap_rights_t, 3009 * but we do with the new filedesc. 3010 */ 3011 if (fp->f_type == DTYPE_CAPABILITY) { 3012 kif->kf_flags |= KF_FLAG_CAPABILITY; 3013 (void)cap_funwrap(fp, 0, &fp); 3014 } 3015 #else 3016 KASSERT(fp->f_type != DTYPE_CAPABILITY, 3017 ("sysctl_kern_proc_ofiledesc: saw capability")); 3018 #endif 3019 switch (fp->f_type) { 3020 case DTYPE_VNODE: 3021 kif->kf_type = KF_TYPE_VNODE; 3022 vp = fp->f_vnode; 3023 break; 3024 3025 case DTYPE_SOCKET: 3026 kif->kf_type = KF_TYPE_SOCKET; 3027 so = fp->f_data; 3028 break; 3029 3030 case DTYPE_PIPE: 3031 kif->kf_type = KF_TYPE_PIPE; 3032 break; 3033 3034 case DTYPE_FIFO: 3035 kif->kf_type = KF_TYPE_FIFO; 3036 vp = fp->f_vnode; 3037 break; 3038 3039 case DTYPE_KQUEUE: 3040 kif->kf_type = KF_TYPE_KQUEUE; 3041 break; 3042 3043 case DTYPE_CRYPTO: 3044 kif->kf_type = KF_TYPE_CRYPTO; 3045 break; 3046 3047 case DTYPE_MQUEUE: 3048 kif->kf_type = KF_TYPE_MQUEUE; 3049 break; 3050 3051 case DTYPE_SHM: 3052 kif->kf_type = KF_TYPE_SHM; 3053 shmfd = fp->f_data; 3054 break; 3055 3056 case DTYPE_SEM: 3057 kif->kf_type = KF_TYPE_SEM; 3058 break; 3059 3060 case DTYPE_PTS: 3061 kif->kf_type = KF_TYPE_PTS; 3062 tp = fp->f_data; 3063 break; 3064 3065 #ifdef PROCDESC 3066 case DTYPE_PROCDESC: 3067 kif->kf_type = KF_TYPE_PROCDESC; 3068 break; 3069 #endif 3070 3071 default: 3072 kif->kf_type = KF_TYPE_UNKNOWN; 3073 break; 3074 } 3075 kif->kf_ref_count = fp->f_count; 3076 if (fp->f_flag & FREAD) 3077 kif->kf_flags |= KF_FLAG_READ; 3078 if (fp->f_flag & FWRITE) 3079 kif->kf_flags |= KF_FLAG_WRITE; 3080 if (fp->f_flag & FAPPEND) 3081 kif->kf_flags |= KF_FLAG_APPEND; 3082 if (fp->f_flag & FASYNC) 3083 kif->kf_flags |= KF_FLAG_ASYNC; 3084 if (fp->f_flag & FFSYNC) 3085 kif->kf_flags |= KF_FLAG_FSYNC; 3086 if (fp->f_flag & FNONBLOCK) 3087 kif->kf_flags |= KF_FLAG_NONBLOCK; 3088 if (fp->f_flag & O_DIRECT) 3089 kif->kf_flags |= KF_FLAG_DIRECT; 3090 if (fp->f_flag & FHASLOCK) 3091 kif->kf_flags |= KF_FLAG_HASLOCK; 3092 kif->kf_offset = fp->f_offset; 3093 if (vp != NULL) { 3094 vref(vp); 3095 switch (vp->v_type) { 3096 case VNON: 3097 kif->kf_vnode_type = KF_VTYPE_VNON; 3098 break; 3099 case VREG: 3100 kif->kf_vnode_type = KF_VTYPE_VREG; 3101 break; 3102 case VDIR: 3103 kif->kf_vnode_type = KF_VTYPE_VDIR; 3104 break; 3105 case VBLK: 3106 kif->kf_vnode_type = KF_VTYPE_VBLK; 3107 break; 3108 case VCHR: 3109 kif->kf_vnode_type = KF_VTYPE_VCHR; 3110 break; 3111 case VLNK: 3112 kif->kf_vnode_type = KF_VTYPE_VLNK; 3113 break; 3114 case VSOCK: 3115 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3116 break; 3117 case VFIFO: 3118 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3119 break; 3120 case VBAD: 3121 kif->kf_vnode_type = KF_VTYPE_VBAD; 3122 break; 3123 default: 3124 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3125 break; 3126 } 3127 /* 3128 * It is OK to drop the filedesc lock here as we will 3129 * re-validate and re-evaluate its properties when 3130 * the loop continues. 3131 */ 3132 freepath = NULL; 3133 fullpath = "-"; 3134 FILEDESC_SUNLOCK(fdp); 3135 vn_fullpath(curthread, vp, &fullpath, &freepath); 3136 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 3137 vrele(vp); 3138 VFS_UNLOCK_GIANT(vfslocked); 3139 strlcpy(kif->kf_path, fullpath, 3140 sizeof(kif->kf_path)); 3141 if (freepath != NULL) 3142 free(freepath, M_TEMP); 3143 FILEDESC_SLOCK(fdp); 3144 } 3145 if (so != NULL) { 3146 struct sockaddr *sa; 3147 3148 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3149 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3150 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3151 free(sa, M_SONAME); 3152 } 3153 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3154 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3155 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3156 free(sa, M_SONAME); 3157 } 3158 kif->kf_sock_domain = 3159 so->so_proto->pr_domain->dom_family; 3160 kif->kf_sock_type = so->so_type; 3161 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3162 } 3163 if (tp != NULL) { 3164 strlcpy(kif->kf_path, tty_devname(tp), 3165 sizeof(kif->kf_path)); 3166 } 3167 if (shmfd != NULL) 3168 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3169 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3170 if (error) 3171 break; 3172 } 3173 FILEDESC_SUNLOCK(fdp); 3174 fddrop(fdp); 3175 free(kif, M_TEMP); 3176 return (0); 3177 } 3178 3179 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD, 3180 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries"); 3181 #endif /* COMPAT_FREEBSD7 */ 3182 3183 #ifdef KINFO_FILE_SIZE 3184 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3185 #endif 3186 3187 static int 3188 export_fd_for_sysctl(void *data, int type, int fd, int fflags, int refcnt, 3189 int64_t offset, int fd_is_cap, cap_rights_t fd_cap_rights, 3190 struct kinfo_file *kif, struct sysctl_req *req) 3191 { 3192 struct { 3193 int fflag; 3194 int kf_fflag; 3195 } fflags_table[] = { 3196 { FAPPEND, KF_FLAG_APPEND }, 3197 { FASYNC, KF_FLAG_ASYNC }, 3198 { FFSYNC, KF_FLAG_FSYNC }, 3199 { FHASLOCK, KF_FLAG_HASLOCK }, 3200 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3201 { FREAD, KF_FLAG_READ }, 3202 { FWRITE, KF_FLAG_WRITE }, 3203 { O_CREAT, KF_FLAG_CREAT }, 3204 { O_DIRECT, KF_FLAG_DIRECT }, 3205 { O_EXCL, KF_FLAG_EXCL }, 3206 { O_EXEC, KF_FLAG_EXEC }, 3207 { O_EXLOCK, KF_FLAG_EXLOCK }, 3208 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3209 { O_SHLOCK, KF_FLAG_SHLOCK }, 3210 { O_TRUNC, KF_FLAG_TRUNC } 3211 }; 3212 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3213 struct vnode *vp; 3214 int error, vfslocked; 3215 unsigned int i; 3216 3217 bzero(kif, sizeof(*kif)); 3218 switch (type) { 3219 case KF_TYPE_FIFO: 3220 case KF_TYPE_VNODE: 3221 vp = (struct vnode *)data; 3222 error = fill_vnode_info(vp, kif); 3223 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 3224 vrele(vp); 3225 VFS_UNLOCK_GIANT(vfslocked); 3226 break; 3227 case KF_TYPE_SOCKET: 3228 error = fill_socket_info((struct socket *)data, kif); 3229 break; 3230 case KF_TYPE_PIPE: 3231 error = fill_pipe_info((struct pipe *)data, kif); 3232 break; 3233 case KF_TYPE_PTS: 3234 error = fill_pts_info((struct tty *)data, kif); 3235 break; 3236 case KF_TYPE_PROCDESC: 3237 error = fill_procdesc_info((struct procdesc *)data, kif); 3238 break; 3239 case KF_TYPE_SHM: 3240 error = fill_shm_info((struct file *)data, kif); 3241 break; 3242 default: 3243 error = 0; 3244 } 3245 if (error == 0) 3246 kif->kf_status |= KF_ATTR_VALID; 3247 3248 /* 3249 * Translate file access flags. 3250 */ 3251 for (i = 0; i < NFFLAGS; i++) 3252 if (fflags & fflags_table[i].fflag) 3253 kif->kf_flags |= fflags_table[i].kf_fflag; 3254 if (fd_is_cap) 3255 kif->kf_flags |= KF_FLAG_CAPABILITY; 3256 if (fd_is_cap) 3257 kif->kf_cap_rights = fd_cap_rights; 3258 kif->kf_fd = fd; 3259 kif->kf_type = type; 3260 kif->kf_ref_count = refcnt; 3261 kif->kf_offset = offset; 3262 /* Pack record size down */ 3263 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3264 strlen(kif->kf_path) + 1; 3265 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3266 error = SYSCTL_OUT(req, kif, kif->kf_structsize); 3267 return (error); 3268 } 3269 3270 /* 3271 * Get per-process file descriptors for use by procstat(1), et al. 3272 */ 3273 static int 3274 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3275 { 3276 struct file *fp; 3277 struct filedesc *fdp; 3278 struct kinfo_file *kif; 3279 struct proc *p; 3280 struct vnode *cttyvp, *textvp, *tracevp; 3281 size_t oldidx; 3282 int64_t offset; 3283 void *data; 3284 int error, i, *name; 3285 int fd_is_cap, type, refcnt, fflags; 3286 cap_rights_t fd_cap_rights; 3287 3288 name = (int *)arg1; 3289 if ((p = pfind((pid_t)name[0])) == NULL) 3290 return (ESRCH); 3291 if ((error = p_candebug(curthread, p))) { 3292 PROC_UNLOCK(p); 3293 return (error); 3294 } 3295 /* ktrace vnode */ 3296 tracevp = p->p_tracevp; 3297 if (tracevp != NULL) 3298 vref(tracevp); 3299 /* text vnode */ 3300 textvp = p->p_textvp; 3301 if (textvp != NULL) 3302 vref(textvp); 3303 /* Controlling tty. */ 3304 cttyvp = NULL; 3305 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3306 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3307 if (cttyvp != NULL) 3308 vref(cttyvp); 3309 } 3310 fdp = fdhold(p); 3311 PROC_UNLOCK(p); 3312 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3313 if (tracevp != NULL) 3314 export_fd_for_sysctl(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3315 FREAD | FWRITE, -1, -1, 0, 0, kif, req); 3316 if (textvp != NULL) 3317 export_fd_for_sysctl(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3318 FREAD, -1, -1, 0, 0, kif, req); 3319 if (cttyvp != NULL) 3320 export_fd_for_sysctl(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3321 FREAD | FWRITE, -1, -1, 0, 0, kif, req); 3322 if (fdp == NULL) 3323 goto fail; 3324 FILEDESC_SLOCK(fdp); 3325 /* working directory */ 3326 if (fdp->fd_cdir != NULL) { 3327 vref(fdp->fd_cdir); 3328 data = fdp->fd_cdir; 3329 FILEDESC_SUNLOCK(fdp); 3330 export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3331 FREAD, -1, -1, 0, 0, kif, req); 3332 FILEDESC_SLOCK(fdp); 3333 } 3334 /* root directory */ 3335 if (fdp->fd_rdir != NULL) { 3336 vref(fdp->fd_rdir); 3337 data = fdp->fd_rdir; 3338 FILEDESC_SUNLOCK(fdp); 3339 export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3340 FREAD, -1, -1, 0, 0, kif, req); 3341 FILEDESC_SLOCK(fdp); 3342 } 3343 /* jail directory */ 3344 if (fdp->fd_jdir != NULL) { 3345 vref(fdp->fd_jdir); 3346 data = fdp->fd_jdir; 3347 FILEDESC_SUNLOCK(fdp); 3348 export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3349 FREAD, -1, -1, 0, 0, kif, req); 3350 FILEDESC_SLOCK(fdp); 3351 } 3352 for (i = 0; i < fdp->fd_nfiles; i++) { 3353 if ((fp = fdp->fd_ofiles[i]) == NULL) 3354 continue; 3355 data = NULL; 3356 fd_is_cap = 0; 3357 fd_cap_rights = 0; 3358 3359 #ifdef CAPABILITIES 3360 /* 3361 * When reporting a capability, most fields will be from the 3362 * underlying object, but do mark as a capability and export 3363 * the capability rights mask. 3364 */ 3365 if (fp->f_type == DTYPE_CAPABILITY) { 3366 fd_is_cap = 1; 3367 fd_cap_rights = cap_rights(fp); 3368 (void)cap_funwrap(fp, 0, &fp); 3369 } 3370 #else /* !CAPABILITIES */ 3371 KASSERT(fp->f_type != DTYPE_CAPABILITY, 3372 ("sysctl_kern_proc_filedesc: saw capability")); 3373 #endif 3374 switch (fp->f_type) { 3375 case DTYPE_VNODE: 3376 type = KF_TYPE_VNODE; 3377 vref(fp->f_vnode); 3378 data = fp->f_vnode; 3379 break; 3380 3381 case DTYPE_SOCKET: 3382 type = KF_TYPE_SOCKET; 3383 data = fp->f_data; 3384 break; 3385 3386 case DTYPE_PIPE: 3387 type = KF_TYPE_PIPE; 3388 data = fp->f_data; 3389 break; 3390 3391 case DTYPE_FIFO: 3392 type = KF_TYPE_FIFO; 3393 vref(fp->f_vnode); 3394 data = fp->f_vnode; 3395 break; 3396 3397 case DTYPE_KQUEUE: 3398 type = KF_TYPE_KQUEUE; 3399 break; 3400 3401 case DTYPE_CRYPTO: 3402 type = KF_TYPE_CRYPTO; 3403 break; 3404 3405 case DTYPE_MQUEUE: 3406 type = KF_TYPE_MQUEUE; 3407 break; 3408 3409 case DTYPE_SHM: 3410 type = KF_TYPE_SHM; 3411 data = fp; 3412 break; 3413 3414 case DTYPE_SEM: 3415 type = KF_TYPE_SEM; 3416 break; 3417 3418 case DTYPE_PTS: 3419 type = KF_TYPE_PTS; 3420 data = fp->f_data; 3421 break; 3422 3423 #ifdef PROCDESC 3424 case DTYPE_PROCDESC: 3425 type = KF_TYPE_PROCDESC; 3426 data = fp->f_data; 3427 break; 3428 #endif 3429 3430 default: 3431 type = KF_TYPE_UNKNOWN; 3432 break; 3433 } 3434 refcnt = fp->f_count; 3435 fflags = fp->f_flag; 3436 offset = fp->f_offset; 3437 3438 /* 3439 * Create sysctl entry. 3440 * It is OK to drop the filedesc lock here as we will 3441 * re-validate and re-evaluate its properties when 3442 * the loop continues. 3443 */ 3444 oldidx = req->oldidx; 3445 if (type == KF_TYPE_VNODE || type == KF_TYPE_FIFO) 3446 FILEDESC_SUNLOCK(fdp); 3447 error = export_fd_for_sysctl(data, type, i, fflags, refcnt, 3448 offset, fd_is_cap, fd_cap_rights, kif, req); 3449 if (type == KF_TYPE_VNODE || type == KF_TYPE_FIFO) 3450 FILEDESC_SLOCK(fdp); 3451 if (error) { 3452 if (error == ENOMEM) { 3453 /* 3454 * The hack to keep the ABI of sysctl 3455 * kern.proc.filedesc intact, but not 3456 * to account a partially copied 3457 * kinfo_file into the oldidx. 3458 */ 3459 req->oldidx = oldidx; 3460 error = 0; 3461 } 3462 break; 3463 } 3464 } 3465 FILEDESC_SUNLOCK(fdp); 3466 fail: 3467 if (fdp != NULL) 3468 fddrop(fdp); 3469 free(kif, M_TEMP); 3470 return (error); 3471 } 3472 3473 int 3474 vntype_to_kinfo(int vtype) 3475 { 3476 struct { 3477 int vtype; 3478 int kf_vtype; 3479 } vtypes_table[] = { 3480 { VBAD, KF_VTYPE_VBAD }, 3481 { VBLK, KF_VTYPE_VBLK }, 3482 { VCHR, KF_VTYPE_VCHR }, 3483 { VDIR, KF_VTYPE_VDIR }, 3484 { VFIFO, KF_VTYPE_VFIFO }, 3485 { VLNK, KF_VTYPE_VLNK }, 3486 { VNON, KF_VTYPE_VNON }, 3487 { VREG, KF_VTYPE_VREG }, 3488 { VSOCK, KF_VTYPE_VSOCK } 3489 }; 3490 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3491 unsigned int i; 3492 3493 /* 3494 * Perform vtype translation. 3495 */ 3496 for (i = 0; i < NVTYPES; i++) 3497 if (vtypes_table[i].vtype == vtype) 3498 break; 3499 if (i < NVTYPES) 3500 return (vtypes_table[i].kf_vtype); 3501 3502 return (KF_VTYPE_UNKNOWN); 3503 } 3504 3505 static int 3506 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3507 { 3508 struct vattr va; 3509 char *fullpath, *freepath; 3510 int error, vfslocked; 3511 3512 if (vp == NULL) 3513 return (1); 3514 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3515 freepath = NULL; 3516 fullpath = "-"; 3517 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3518 if (error == 0) { 3519 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3520 } 3521 if (freepath != NULL) 3522 free(freepath, M_TEMP); 3523 3524 /* 3525 * Retrieve vnode attributes. 3526 */ 3527 va.va_fsid = VNOVAL; 3528 va.va_rdev = NODEV; 3529 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 3530 vn_lock(vp, LK_SHARED | LK_RETRY); 3531 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3532 VOP_UNLOCK(vp, 0); 3533 VFS_UNLOCK_GIANT(vfslocked); 3534 if (error != 0) 3535 return (error); 3536 if (va.va_fsid != VNOVAL) 3537 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3538 else 3539 kif->kf_un.kf_file.kf_file_fsid = 3540 vp->v_mount->mnt_stat.f_fsid.val[0]; 3541 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3542 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3543 kif->kf_un.kf_file.kf_file_size = va.va_size; 3544 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3545 return (0); 3546 } 3547 3548 static int 3549 fill_socket_info(struct socket *so, struct kinfo_file *kif) 3550 { 3551 struct sockaddr *sa; 3552 struct inpcb *inpcb; 3553 struct unpcb *unpcb; 3554 int error; 3555 3556 if (so == NULL) 3557 return (1); 3558 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3559 kif->kf_sock_type = so->so_type; 3560 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3561 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3562 switch(kif->kf_sock_domain) { 3563 case AF_INET: 3564 case AF_INET6: 3565 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3566 if (so->so_pcb != NULL) { 3567 inpcb = (struct inpcb *)(so->so_pcb); 3568 kif->kf_un.kf_sock.kf_sock_inpcb = 3569 (uintptr_t)inpcb->inp_ppcb; 3570 } 3571 } 3572 break; 3573 case AF_UNIX: 3574 if (so->so_pcb != NULL) { 3575 unpcb = (struct unpcb *)(so->so_pcb); 3576 if (unpcb->unp_conn) { 3577 kif->kf_un.kf_sock.kf_sock_unpconn = 3578 (uintptr_t)unpcb->unp_conn; 3579 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3580 so->so_rcv.sb_state; 3581 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3582 so->so_snd.sb_state; 3583 } 3584 } 3585 break; 3586 } 3587 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3588 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3589 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3590 free(sa, M_SONAME); 3591 } 3592 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3593 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3594 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3595 free(sa, M_SONAME); 3596 } 3597 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3598 sizeof(kif->kf_path)); 3599 return (0); 3600 } 3601 3602 static int 3603 fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3604 { 3605 3606 if (tp == NULL) 3607 return (1); 3608 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3609 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3610 return (0); 3611 } 3612 3613 static int 3614 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3615 { 3616 3617 if (pi == NULL) 3618 return (1); 3619 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3620 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3621 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3622 return (0); 3623 } 3624 3625 static int 3626 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3627 { 3628 3629 if (pdp == NULL) 3630 return (1); 3631 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3632 return (0); 3633 } 3634 3635 static int 3636 fill_shm_info(struct file *fp, struct kinfo_file *kif) 3637 { 3638 struct thread *td; 3639 struct stat sb; 3640 3641 td = curthread; 3642 if (fp->f_data == NULL) 3643 return (1); 3644 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3645 return (1); 3646 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3647 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3648 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3649 return (0); 3650 } 3651 3652 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD, 3653 sysctl_kern_proc_filedesc, "Process filedesc entries"); 3654 3655 #ifdef DDB 3656 /* 3657 * For the purposes of debugging, generate a human-readable string for the 3658 * file type. 3659 */ 3660 static const char * 3661 file_type_to_name(short type) 3662 { 3663 3664 switch (type) { 3665 case 0: 3666 return ("zero"); 3667 case DTYPE_VNODE: 3668 return ("vnod"); 3669 case DTYPE_SOCKET: 3670 return ("sock"); 3671 case DTYPE_PIPE: 3672 return ("pipe"); 3673 case DTYPE_FIFO: 3674 return ("fifo"); 3675 case DTYPE_KQUEUE: 3676 return ("kque"); 3677 case DTYPE_CRYPTO: 3678 return ("crpt"); 3679 case DTYPE_MQUEUE: 3680 return ("mque"); 3681 case DTYPE_SHM: 3682 return ("shm"); 3683 case DTYPE_SEM: 3684 return ("ksem"); 3685 default: 3686 return ("unkn"); 3687 } 3688 } 3689 3690 /* 3691 * For the purposes of debugging, identify a process (if any, perhaps one of 3692 * many) that references the passed file in its file descriptor array. Return 3693 * NULL if none. 3694 */ 3695 static struct proc * 3696 file_to_first_proc(struct file *fp) 3697 { 3698 struct filedesc *fdp; 3699 struct proc *p; 3700 int n; 3701 3702 FOREACH_PROC_IN_SYSTEM(p) { 3703 if (p->p_state == PRS_NEW) 3704 continue; 3705 fdp = p->p_fd; 3706 if (fdp == NULL) 3707 continue; 3708 for (n = 0; n < fdp->fd_nfiles; n++) { 3709 if (fp == fdp->fd_ofiles[n]) 3710 return (p); 3711 } 3712 } 3713 return (NULL); 3714 } 3715 3716 static void 3717 db_print_file(struct file *fp, int header) 3718 { 3719 struct proc *p; 3720 3721 if (header) 3722 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3723 "File", "Type", "Data", "Flag", "GCFl", "Count", 3724 "MCount", "Vnode", "FPID", "FCmd"); 3725 p = file_to_first_proc(fp); 3726 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3727 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3728 0, fp->f_count, 0, fp->f_vnode, 3729 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3730 } 3731 3732 DB_SHOW_COMMAND(file, db_show_file) 3733 { 3734 struct file *fp; 3735 3736 if (!have_addr) { 3737 db_printf("usage: show file <addr>\n"); 3738 return; 3739 } 3740 fp = (struct file *)addr; 3741 db_print_file(fp, 1); 3742 } 3743 3744 DB_SHOW_COMMAND(files, db_show_files) 3745 { 3746 struct filedesc *fdp; 3747 struct file *fp; 3748 struct proc *p; 3749 int header; 3750 int n; 3751 3752 header = 1; 3753 FOREACH_PROC_IN_SYSTEM(p) { 3754 if (p->p_state == PRS_NEW) 3755 continue; 3756 if ((fdp = p->p_fd) == NULL) 3757 continue; 3758 for (n = 0; n < fdp->fd_nfiles; ++n) { 3759 if ((fp = fdp->fd_ofiles[n]) == NULL) 3760 continue; 3761 db_print_file(fp, header); 3762 header = 0; 3763 } 3764 } 3765 } 3766 #endif 3767 3768 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3769 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3770 3771 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3772 &maxfiles, 0, "Maximum number of files"); 3773 3774 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3775 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3776 3777 /* ARGSUSED*/ 3778 static void 3779 filelistinit(void *dummy) 3780 { 3781 3782 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3783 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3784 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3785 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3786 } 3787 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3788 3789 /*-------------------------------------------------------------------*/ 3790 3791 static int 3792 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3793 int flags, struct thread *td) 3794 { 3795 3796 return (EBADF); 3797 } 3798 3799 static int 3800 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3801 struct thread *td) 3802 { 3803 3804 return (EINVAL); 3805 } 3806 3807 static int 3808 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3809 struct thread *td) 3810 { 3811 3812 return (EBADF); 3813 } 3814 3815 static int 3816 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3817 struct thread *td) 3818 { 3819 3820 return (0); 3821 } 3822 3823 static int 3824 badfo_kqfilter(struct file *fp, struct knote *kn) 3825 { 3826 3827 return (EBADF); 3828 } 3829 3830 static int 3831 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3832 struct thread *td) 3833 { 3834 3835 return (EBADF); 3836 } 3837 3838 static int 3839 badfo_close(struct file *fp, struct thread *td) 3840 { 3841 3842 return (EBADF); 3843 } 3844 3845 static int 3846 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3847 struct thread *td) 3848 { 3849 3850 return (EBADF); 3851 } 3852 3853 static int 3854 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3855 struct thread *td) 3856 { 3857 3858 return (EBADF); 3859 } 3860 3861 struct fileops badfileops = { 3862 .fo_read = badfo_readwrite, 3863 .fo_write = badfo_readwrite, 3864 .fo_truncate = badfo_truncate, 3865 .fo_ioctl = badfo_ioctl, 3866 .fo_poll = badfo_poll, 3867 .fo_kqfilter = badfo_kqfilter, 3868 .fo_stat = badfo_stat, 3869 .fo_close = badfo_close, 3870 .fo_chmod = badfo_chmod, 3871 .fo_chown = badfo_chown, 3872 }; 3873 3874 int 3875 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3876 struct thread *td) 3877 { 3878 3879 return (EINVAL); 3880 } 3881 3882 int 3883 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3884 struct thread *td) 3885 { 3886 3887 return (EINVAL); 3888 } 3889 3890 /*-------------------------------------------------------------------*/ 3891 3892 /* 3893 * File Descriptor pseudo-device driver (/dev/fd/). 3894 * 3895 * Opening minor device N dup()s the file (if any) connected to file 3896 * descriptor N belonging to the calling process. Note that this driver 3897 * consists of only the ``open()'' routine, because all subsequent 3898 * references to this file will be direct to the other driver. 3899 * 3900 * XXX: we could give this one a cloning event handler if necessary. 3901 */ 3902 3903 /* ARGSUSED */ 3904 static int 3905 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 3906 { 3907 3908 /* 3909 * XXX Kludge: set curthread->td_dupfd to contain the value of the 3910 * the file descriptor being sought for duplication. The error 3911 * return ensures that the vnode for this device will be released 3912 * by vn_open. Open will detect this special error and take the 3913 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 3914 * will simply report the error. 3915 */ 3916 td->td_dupfd = dev2unit(dev); 3917 return (ENODEV); 3918 } 3919 3920 static struct cdevsw fildesc_cdevsw = { 3921 .d_version = D_VERSION, 3922 .d_open = fdopen, 3923 .d_name = "FD", 3924 }; 3925 3926 static void 3927 fildesc_drvinit(void *unused) 3928 { 3929 struct cdev *dev; 3930 3931 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 3932 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 3933 make_dev_alias(dev, "stdin"); 3934 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 3935 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 3936 make_dev_alias(dev, "stdout"); 3937 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 3938 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 3939 make_dev_alias(dev, "stderr"); 3940 } 3941 3942 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 3943