1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_capsicum.h" 41 #include "opt_compat.h" 42 #include "opt_ddb.h" 43 #include "opt_ktrace.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 48 #include <sys/capsicum.h> 49 #include <sys/conf.h> 50 #include <sys/domain.h> 51 #include <sys/fcntl.h> 52 #include <sys/file.h> 53 #include <sys/filedesc.h> 54 #include <sys/filio.h> 55 #include <sys/jail.h> 56 #include <sys/kernel.h> 57 #include <sys/ksem.h> 58 #include <sys/limits.h> 59 #include <sys/lock.h> 60 #include <sys/malloc.h> 61 #include <sys/mman.h> 62 #include <sys/mount.h> 63 #include <sys/mqueue.h> 64 #include <sys/mutex.h> 65 #include <sys/namei.h> 66 #include <sys/selinfo.h> 67 #include <sys/pipe.h> 68 #include <sys/priv.h> 69 #include <sys/proc.h> 70 #include <sys/procdesc.h> 71 #include <sys/protosw.h> 72 #include <sys/racct.h> 73 #include <sys/resourcevar.h> 74 #include <sys/sbuf.h> 75 #include <sys/signalvar.h> 76 #include <sys/socketvar.h> 77 #include <sys/stat.h> 78 #include <sys/sx.h> 79 #include <sys/syscallsubr.h> 80 #include <sys/sysctl.h> 81 #include <sys/sysproto.h> 82 #include <sys/tty.h> 83 #include <sys/unistd.h> 84 #include <sys/un.h> 85 #include <sys/unpcb.h> 86 #include <sys/user.h> 87 #include <sys/vnode.h> 88 #ifdef KTRACE 89 #include <sys/ktrace.h> 90 #endif 91 92 #include <net/vnet.h> 93 94 #include <netinet/in.h> 95 #include <netinet/in_pcb.h> 96 97 #include <security/audit/audit.h> 98 99 #include <vm/uma.h> 100 #include <vm/vm.h> 101 102 #include <ddb/ddb.h> 103 104 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 105 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 106 "file desc to leader structures"); 107 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 108 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 109 110 MALLOC_DECLARE(M_FADVISE); 111 112 static uma_zone_t file_zone; 113 114 void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value); 115 116 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 117 struct thread *td, int holdleaders); 118 static int fd_first_free(struct filedesc *fdp, int low, int size); 119 static int fd_last_used(struct filedesc *fdp, int size); 120 static void fdgrowtable(struct filedesc *fdp, int nfd); 121 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 122 static void fdunused(struct filedesc *fdp, int fd); 123 static void fdused(struct filedesc *fdp, int fd); 124 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); 125 static int fill_procdesc_info(struct procdesc *pdp, 126 struct kinfo_file *kif); 127 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif); 128 static int fill_sem_info(struct file *fp, struct kinfo_file *kif); 129 static int fill_shm_info(struct file *fp, struct kinfo_file *kif); 130 static int fill_socket_info(struct socket *so, struct kinfo_file *kif); 131 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); 132 static int getmaxfd(struct proc *p); 133 134 /* 135 * Each process has: 136 * 137 * - An array of open file descriptors (fd_ofiles) 138 * - An array of file flags (fd_ofileflags) 139 * - A bitmap recording which descriptors are in use (fd_map) 140 * 141 * A process starts out with NDFILE descriptors. The value of NDFILE has 142 * been selected based the historical limit of 20 open files, and an 143 * assumption that the majority of processes, especially short-lived 144 * processes like shells, will never need more. 145 * 146 * If this initial allocation is exhausted, a larger descriptor table and 147 * map are allocated dynamically, and the pointers in the process's struct 148 * filedesc are updated to point to those. This is repeated every time 149 * the process runs out of file descriptors (provided it hasn't hit its 150 * resource limit). 151 * 152 * Since threads may hold references to individual descriptor table 153 * entries, the tables are never freed. Instead, they are placed on a 154 * linked list and freed only when the struct filedesc is released. 155 */ 156 #define NDFILE 20 157 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 158 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 159 #define NDSLOT(x) ((x) / NDENTRIES) 160 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 161 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 162 163 /* 164 * SLIST entry used to keep track of ofiles which must be reclaimed when 165 * the process exits. 166 */ 167 struct freetable { 168 struct filedescent *ft_table; 169 SLIST_ENTRY(freetable) ft_next; 170 }; 171 172 /* 173 * Initial allocation: a filedesc structure + the head of SLIST used to 174 * keep track of old ofiles + enough space for NDFILE descriptors. 175 */ 176 struct filedesc0 { 177 struct filedesc fd_fd; 178 SLIST_HEAD(, freetable) fd_free; 179 struct filedescent fd_dfiles[NDFILE]; 180 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 181 }; 182 183 /* 184 * Descriptor management. 185 */ 186 volatile int openfiles; /* actual number of open files */ 187 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 188 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 189 190 /* A mutex to protect the association between a proc and filedesc. */ 191 static struct mtx fdesc_mtx; 192 193 /* 194 * If low >= size, just return low. Otherwise find the first zero bit in the 195 * given bitmap, starting at low and not exceeding size - 1. Return size if 196 * not found. 197 */ 198 static int 199 fd_first_free(struct filedesc *fdp, int low, int size) 200 { 201 NDSLOTTYPE *map = fdp->fd_map; 202 NDSLOTTYPE mask; 203 int off, maxoff; 204 205 if (low >= size) 206 return (low); 207 208 off = NDSLOT(low); 209 if (low % NDENTRIES) { 210 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 211 if ((mask &= ~map[off]) != 0UL) 212 return (off * NDENTRIES + ffsl(mask) - 1); 213 ++off; 214 } 215 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 216 if (map[off] != ~0UL) 217 return (off * NDENTRIES + ffsl(~map[off]) - 1); 218 return (size); 219 } 220 221 /* 222 * Find the highest non-zero bit in the given bitmap, starting at 0 and 223 * not exceeding size - 1. Return -1 if not found. 224 */ 225 static int 226 fd_last_used(struct filedesc *fdp, int size) 227 { 228 NDSLOTTYPE *map = fdp->fd_map; 229 NDSLOTTYPE mask; 230 int off, minoff; 231 232 off = NDSLOT(size); 233 if (size % NDENTRIES) { 234 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 235 if ((mask &= map[off]) != 0) 236 return (off * NDENTRIES + flsl(mask) - 1); 237 --off; 238 } 239 for (minoff = NDSLOT(0); off >= minoff; --off) 240 if (map[off] != 0) 241 return (off * NDENTRIES + flsl(map[off]) - 1); 242 return (-1); 243 } 244 245 static int 246 fdisused(struct filedesc *fdp, int fd) 247 { 248 249 FILEDESC_LOCK_ASSERT(fdp); 250 251 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 252 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 253 254 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 255 } 256 257 /* 258 * Mark a file descriptor as used. 259 */ 260 static void 261 fdused(struct filedesc *fdp, int fd) 262 { 263 264 FILEDESC_XLOCK_ASSERT(fdp); 265 266 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 267 268 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 269 if (fd > fdp->fd_lastfile) 270 fdp->fd_lastfile = fd; 271 if (fd == fdp->fd_freefile) 272 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 273 } 274 275 /* 276 * Mark a file descriptor as unused. 277 */ 278 static void 279 fdunused(struct filedesc *fdp, int fd) 280 { 281 282 FILEDESC_XLOCK_ASSERT(fdp); 283 284 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 285 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 286 ("fd=%d is still in use", fd)); 287 288 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 289 if (fd < fdp->fd_freefile) 290 fdp->fd_freefile = fd; 291 if (fd == fdp->fd_lastfile) 292 fdp->fd_lastfile = fd_last_used(fdp, fd); 293 } 294 295 /* 296 * Free a file descriptor. 297 * 298 * Avoid some work if fdp is about to be destroyed. 299 */ 300 static inline void 301 _fdfree(struct filedesc *fdp, int fd, int last) 302 { 303 struct filedescent *fde; 304 305 fde = &fdp->fd_ofiles[fd]; 306 filecaps_free(&fde->fde_caps); 307 if (last) 308 return; 309 bzero(fde, sizeof(*fde)); 310 fdunused(fdp, fd); 311 } 312 313 static inline void 314 fdfree(struct filedesc *fdp, int fd) 315 { 316 317 _fdfree(fdp, fd, 0); 318 } 319 320 static inline void 321 fdfree_last(struct filedesc *fdp, int fd) 322 { 323 324 _fdfree(fdp, fd, 1); 325 } 326 327 /* 328 * System calls on descriptors. 329 */ 330 #ifndef _SYS_SYSPROTO_H_ 331 struct getdtablesize_args { 332 int dummy; 333 }; 334 #endif 335 /* ARGSUSED */ 336 int 337 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 338 { 339 struct proc *p = td->td_proc; 340 uint64_t lim; 341 342 PROC_LOCK(p); 343 td->td_retval[0] = 344 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 345 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 346 PROC_UNLOCK(p); 347 if (lim < td->td_retval[0]) 348 td->td_retval[0] = lim; 349 return (0); 350 } 351 352 /* 353 * Duplicate a file descriptor to a particular value. 354 * 355 * Note: keep in mind that a potential race condition exists when closing 356 * descriptors from a shared descriptor table (via rfork). 357 */ 358 #ifndef _SYS_SYSPROTO_H_ 359 struct dup2_args { 360 u_int from; 361 u_int to; 362 }; 363 #endif 364 /* ARGSUSED */ 365 int 366 sys_dup2(struct thread *td, struct dup2_args *uap) 367 { 368 369 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 370 td->td_retval)); 371 } 372 373 /* 374 * Duplicate a file descriptor. 375 */ 376 #ifndef _SYS_SYSPROTO_H_ 377 struct dup_args { 378 u_int fd; 379 }; 380 #endif 381 /* ARGSUSED */ 382 int 383 sys_dup(struct thread *td, struct dup_args *uap) 384 { 385 386 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 387 } 388 389 /* 390 * The file control system call. 391 */ 392 #ifndef _SYS_SYSPROTO_H_ 393 struct fcntl_args { 394 int fd; 395 int cmd; 396 long arg; 397 }; 398 #endif 399 /* ARGSUSED */ 400 int 401 sys_fcntl(struct thread *td, struct fcntl_args *uap) 402 { 403 struct flock fl; 404 struct __oflock ofl; 405 intptr_t arg; 406 int error; 407 int cmd; 408 409 error = 0; 410 cmd = uap->cmd; 411 switch (uap->cmd) { 412 case F_OGETLK: 413 case F_OSETLK: 414 case F_OSETLKW: 415 /* 416 * Convert old flock structure to new. 417 */ 418 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 419 fl.l_start = ofl.l_start; 420 fl.l_len = ofl.l_len; 421 fl.l_pid = ofl.l_pid; 422 fl.l_type = ofl.l_type; 423 fl.l_whence = ofl.l_whence; 424 fl.l_sysid = 0; 425 426 switch (uap->cmd) { 427 case F_OGETLK: 428 cmd = F_GETLK; 429 break; 430 case F_OSETLK: 431 cmd = F_SETLK; 432 break; 433 case F_OSETLKW: 434 cmd = F_SETLKW; 435 break; 436 } 437 arg = (intptr_t)&fl; 438 break; 439 case F_GETLK: 440 case F_SETLK: 441 case F_SETLKW: 442 case F_SETLK_REMOTE: 443 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 444 arg = (intptr_t)&fl; 445 break; 446 default: 447 arg = uap->arg; 448 break; 449 } 450 if (error) 451 return (error); 452 error = kern_fcntl(td, uap->fd, cmd, arg); 453 if (error) 454 return (error); 455 if (uap->cmd == F_OGETLK) { 456 ofl.l_start = fl.l_start; 457 ofl.l_len = fl.l_len; 458 ofl.l_pid = fl.l_pid; 459 ofl.l_type = fl.l_type; 460 ofl.l_whence = fl.l_whence; 461 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 462 } else if (uap->cmd == F_GETLK) { 463 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 464 } 465 return (error); 466 } 467 468 int 469 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 470 { 471 struct filedesc *fdp; 472 struct flock *flp; 473 struct file *fp, *fp2; 474 struct filedescent *fde; 475 struct proc *p; 476 struct vnode *vp; 477 cap_rights_t rights; 478 int error, flg, tmp; 479 u_int old, new; 480 uint64_t bsize; 481 off_t foffset; 482 483 error = 0; 484 flg = F_POSIX; 485 p = td->td_proc; 486 fdp = p->p_fd; 487 488 switch (cmd) { 489 case F_DUPFD: 490 tmp = arg; 491 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 492 break; 493 494 case F_DUPFD_CLOEXEC: 495 tmp = arg; 496 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 497 td->td_retval); 498 break; 499 500 case F_DUP2FD: 501 tmp = arg; 502 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 503 break; 504 505 case F_DUP2FD_CLOEXEC: 506 tmp = arg; 507 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 508 td->td_retval); 509 break; 510 511 case F_GETFD: 512 FILEDESC_SLOCK(fdp); 513 if ((fp = fget_locked(fdp, fd)) == NULL) { 514 FILEDESC_SUNLOCK(fdp); 515 error = EBADF; 516 break; 517 } 518 fde = &fdp->fd_ofiles[fd]; 519 td->td_retval[0] = 520 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 521 FILEDESC_SUNLOCK(fdp); 522 break; 523 524 case F_SETFD: 525 FILEDESC_XLOCK(fdp); 526 if ((fp = fget_locked(fdp, fd)) == NULL) { 527 FILEDESC_XUNLOCK(fdp); 528 error = EBADF; 529 break; 530 } 531 fde = &fdp->fd_ofiles[fd]; 532 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 533 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 534 FILEDESC_XUNLOCK(fdp); 535 break; 536 537 case F_GETFL: 538 error = fget_unlocked(fdp, fd, 539 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp, NULL); 540 if (error != 0) 541 break; 542 td->td_retval[0] = OFLAGS(fp->f_flag); 543 fdrop(fp, td); 544 break; 545 546 case F_SETFL: 547 error = fget_unlocked(fdp, fd, 548 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp, NULL); 549 if (error != 0) 550 break; 551 do { 552 tmp = flg = fp->f_flag; 553 tmp &= ~FCNTLFLAGS; 554 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 555 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 556 tmp = fp->f_flag & FNONBLOCK; 557 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 558 if (error != 0) { 559 fdrop(fp, td); 560 break; 561 } 562 tmp = fp->f_flag & FASYNC; 563 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 564 if (error == 0) { 565 fdrop(fp, td); 566 break; 567 } 568 atomic_clear_int(&fp->f_flag, FNONBLOCK); 569 tmp = 0; 570 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 571 fdrop(fp, td); 572 break; 573 574 case F_GETOWN: 575 error = fget_unlocked(fdp, fd, 576 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp, NULL); 577 if (error != 0) 578 break; 579 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 580 if (error == 0) 581 td->td_retval[0] = tmp; 582 fdrop(fp, td); 583 break; 584 585 case F_SETOWN: 586 error = fget_unlocked(fdp, fd, 587 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp, NULL); 588 if (error != 0) 589 break; 590 tmp = arg; 591 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 592 fdrop(fp, td); 593 break; 594 595 case F_SETLK_REMOTE: 596 error = priv_check(td, PRIV_NFS_LOCKD); 597 if (error) 598 return (error); 599 flg = F_REMOTE; 600 goto do_setlk; 601 602 case F_SETLKW: 603 flg |= F_WAIT; 604 /* FALLTHROUGH F_SETLK */ 605 606 case F_SETLK: 607 do_setlk: 608 cap_rights_init(&rights, CAP_FLOCK); 609 error = fget_unlocked(fdp, fd, &rights, 0, &fp, NULL); 610 if (error != 0) 611 break; 612 if (fp->f_type != DTYPE_VNODE) { 613 error = EBADF; 614 fdrop(fp, td); 615 break; 616 } 617 618 flp = (struct flock *)arg; 619 if (flp->l_whence == SEEK_CUR) { 620 foffset = foffset_get(fp); 621 if (foffset < 0 || 622 (flp->l_start > 0 && 623 foffset > OFF_MAX - flp->l_start)) { 624 FILEDESC_SUNLOCK(fdp); 625 error = EOVERFLOW; 626 fdrop(fp, td); 627 break; 628 } 629 flp->l_start += foffset; 630 } 631 632 vp = fp->f_vnode; 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 if (error != 0 || flp->l_type == F_UNLCK || 677 flp->l_type == F_UNLCKSYS) { 678 fdrop(fp, td); 679 break; 680 } 681 682 /* 683 * Check for a race with close. 684 * 685 * The vnode is now advisory locked (or unlocked, but this case 686 * is not really important) as the caller requested. 687 * We had to drop the filedesc lock, so we need to recheck if 688 * the descriptor is still valid, because if it was closed 689 * in the meantime we need to remove advisory lock from the 690 * vnode - close on any descriptor leading to an advisory 691 * locked vnode, removes that lock. 692 * We will return 0 on purpose in that case, as the result of 693 * successful advisory lock might have been externally visible 694 * already. This is fine - effectively we pretend to the caller 695 * that the closing thread was a bit slower and that the 696 * advisory lock succeeded before the close. 697 */ 698 error = fget_unlocked(fdp, fd, &rights, 0, &fp2, NULL); 699 if (error != 0) { 700 fdrop(fp, td); 701 break; 702 } 703 if (fp != fp2) { 704 flp->l_whence = SEEK_SET; 705 flp->l_start = 0; 706 flp->l_len = 0; 707 flp->l_type = F_UNLCK; 708 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 709 F_UNLCK, flp, F_POSIX); 710 } 711 fdrop(fp, td); 712 fdrop(fp2, td); 713 break; 714 715 case F_GETLK: 716 error = fget_unlocked(fdp, fd, 717 cap_rights_init(&rights, CAP_FLOCK), 0, &fp, NULL); 718 if (error != 0) 719 break; 720 if (fp->f_type != DTYPE_VNODE) { 721 error = EBADF; 722 fdrop(fp, td); 723 break; 724 } 725 flp = (struct flock *)arg; 726 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 727 flp->l_type != F_UNLCK) { 728 error = EINVAL; 729 fdrop(fp, td); 730 break; 731 } 732 if (flp->l_whence == SEEK_CUR) { 733 foffset = foffset_get(fp); 734 if ((flp->l_start > 0 && 735 foffset > OFF_MAX - flp->l_start) || 736 (flp->l_start < 0 && 737 foffset < OFF_MIN - flp->l_start)) { 738 FILEDESC_SUNLOCK(fdp); 739 error = EOVERFLOW; 740 fdrop(fp, td); 741 break; 742 } 743 flp->l_start += foffset; 744 } 745 vp = fp->f_vnode; 746 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 747 F_POSIX); 748 fdrop(fp, td); 749 break; 750 751 case F_RDAHEAD: 752 arg = arg ? 128 * 1024: 0; 753 /* FALLTHROUGH */ 754 case F_READAHEAD: 755 error = fget_unlocked(fdp, fd, NULL, 0, &fp, NULL); 756 if (error != 0) 757 break; 758 if (fp->f_type != DTYPE_VNODE) { 759 fdrop(fp, td); 760 error = EBADF; 761 break; 762 } 763 if (arg >= 0) { 764 vp = fp->f_vnode; 765 error = vn_lock(vp, LK_SHARED); 766 if (error != 0) { 767 fdrop(fp, td); 768 break; 769 } 770 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 771 VOP_UNLOCK(vp, 0); 772 fp->f_seqcount = (arg + bsize - 1) / bsize; 773 do { 774 new = old = fp->f_flag; 775 new |= FRDAHEAD; 776 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 777 } else { 778 do { 779 new = old = fp->f_flag; 780 new &= ~FRDAHEAD; 781 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 782 } 783 fdrop(fp, td); 784 break; 785 786 default: 787 error = EINVAL; 788 break; 789 } 790 return (error); 791 } 792 793 static int 794 getmaxfd(struct proc *p) 795 { 796 int maxfd; 797 798 PROC_LOCK(p); 799 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 800 PROC_UNLOCK(p); 801 802 return (maxfd); 803 } 804 805 /* 806 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 807 */ 808 int 809 do_dup(struct thread *td, int flags, int old, int new, 810 register_t *retval) 811 { 812 struct filedesc *fdp; 813 struct filedescent *oldfde, *newfde; 814 struct proc *p; 815 struct file *fp; 816 struct file *delfp; 817 int error, maxfd; 818 819 p = td->td_proc; 820 fdp = p->p_fd; 821 822 /* 823 * Verify we have a valid descriptor to dup from and possibly to 824 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 825 * return EINVAL when the new descriptor is out of bounds. 826 */ 827 if (old < 0) 828 return (EBADF); 829 if (new < 0) 830 return (flags & DUP_FCNTL ? EINVAL : EBADF); 831 maxfd = getmaxfd(p); 832 if (new >= maxfd) 833 return (flags & DUP_FCNTL ? EINVAL : EBADF); 834 835 FILEDESC_XLOCK(fdp); 836 if (fget_locked(fdp, old) == NULL) { 837 FILEDESC_XUNLOCK(fdp); 838 return (EBADF); 839 } 840 oldfde = &fdp->fd_ofiles[old]; 841 if (flags & DUP_FIXED && old == new) { 842 *retval = new; 843 if (flags & DUP_CLOEXEC) 844 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 845 FILEDESC_XUNLOCK(fdp); 846 return (0); 847 } 848 fp = oldfde->fde_file; 849 fhold(fp); 850 851 /* 852 * If the caller specified a file descriptor, make sure the file 853 * table is large enough to hold it, and grab it. Otherwise, just 854 * allocate a new descriptor the usual way. 855 */ 856 if (flags & DUP_FIXED) { 857 if (new >= fdp->fd_nfiles) { 858 /* 859 * The resource limits are here instead of e.g. 860 * fdalloc(), because the file descriptor table may be 861 * shared between processes, so we can't really use 862 * racct_add()/racct_sub(). Instead of counting the 863 * number of actually allocated descriptors, just put 864 * the limit on the size of the file descriptor table. 865 */ 866 #ifdef RACCT 867 PROC_LOCK(p); 868 error = racct_set(p, RACCT_NOFILE, new + 1); 869 PROC_UNLOCK(p); 870 if (error != 0) { 871 FILEDESC_XUNLOCK(fdp); 872 fdrop(fp, td); 873 return (EMFILE); 874 } 875 #endif 876 fdgrowtable_exp(fdp, new + 1); 877 oldfde = &fdp->fd_ofiles[old]; 878 } 879 newfde = &fdp->fd_ofiles[new]; 880 if (newfde->fde_file == NULL) 881 fdused(fdp, new); 882 } else { 883 if ((error = fdalloc(td, new, &new)) != 0) { 884 FILEDESC_XUNLOCK(fdp); 885 fdrop(fp, td); 886 return (error); 887 } 888 newfde = &fdp->fd_ofiles[new]; 889 } 890 891 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 892 KASSERT(old != new, ("new fd is same as old")); 893 894 delfp = newfde->fde_file; 895 896 /* 897 * Duplicate the source descriptor. 898 */ 899 filecaps_free(&newfde->fde_caps); 900 *newfde = *oldfde; 901 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 902 if ((flags & DUP_CLOEXEC) != 0) 903 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 904 else 905 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 906 *retval = new; 907 908 if (delfp != NULL) { 909 (void) closefp(fdp, new, delfp, td, 1); 910 /* closefp() drops the FILEDESC lock for us. */ 911 } else { 912 FILEDESC_XUNLOCK(fdp); 913 } 914 915 return (0); 916 } 917 918 /* 919 * If sigio is on the list associated with a process or process group, 920 * disable signalling from the device, remove sigio from the list and 921 * free sigio. 922 */ 923 void 924 funsetown(struct sigio **sigiop) 925 { 926 struct sigio *sigio; 927 928 SIGIO_LOCK(); 929 sigio = *sigiop; 930 if (sigio == NULL) { 931 SIGIO_UNLOCK(); 932 return; 933 } 934 *(sigio->sio_myref) = NULL; 935 if ((sigio)->sio_pgid < 0) { 936 struct pgrp *pg = (sigio)->sio_pgrp; 937 PGRP_LOCK(pg); 938 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 939 sigio, sio_pgsigio); 940 PGRP_UNLOCK(pg); 941 } else { 942 struct proc *p = (sigio)->sio_proc; 943 PROC_LOCK(p); 944 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 945 sigio, sio_pgsigio); 946 PROC_UNLOCK(p); 947 } 948 SIGIO_UNLOCK(); 949 crfree(sigio->sio_ucred); 950 free(sigio, M_SIGIO); 951 } 952 953 /* 954 * Free a list of sigio structures. 955 * We only need to lock the SIGIO_LOCK because we have made ourselves 956 * inaccessible to callers of fsetown and therefore do not need to lock 957 * the proc or pgrp struct for the list manipulation. 958 */ 959 void 960 funsetownlst(struct sigiolst *sigiolst) 961 { 962 struct proc *p; 963 struct pgrp *pg; 964 struct sigio *sigio; 965 966 sigio = SLIST_FIRST(sigiolst); 967 if (sigio == NULL) 968 return; 969 p = NULL; 970 pg = NULL; 971 972 /* 973 * Every entry of the list should belong 974 * to a single proc or pgrp. 975 */ 976 if (sigio->sio_pgid < 0) { 977 pg = sigio->sio_pgrp; 978 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 979 } else /* if (sigio->sio_pgid > 0) */ { 980 p = sigio->sio_proc; 981 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 982 } 983 984 SIGIO_LOCK(); 985 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 986 *(sigio->sio_myref) = NULL; 987 if (pg != NULL) { 988 KASSERT(sigio->sio_pgid < 0, 989 ("Proc sigio in pgrp sigio list")); 990 KASSERT(sigio->sio_pgrp == pg, 991 ("Bogus pgrp in sigio list")); 992 PGRP_LOCK(pg); 993 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 994 sio_pgsigio); 995 PGRP_UNLOCK(pg); 996 } else /* if (p != NULL) */ { 997 KASSERT(sigio->sio_pgid > 0, 998 ("Pgrp sigio in proc sigio list")); 999 KASSERT(sigio->sio_proc == p, 1000 ("Bogus proc in sigio list")); 1001 PROC_LOCK(p); 1002 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 1003 sio_pgsigio); 1004 PROC_UNLOCK(p); 1005 } 1006 SIGIO_UNLOCK(); 1007 crfree(sigio->sio_ucred); 1008 free(sigio, M_SIGIO); 1009 SIGIO_LOCK(); 1010 } 1011 SIGIO_UNLOCK(); 1012 } 1013 1014 /* 1015 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1016 * 1017 * After permission checking, add a sigio structure to the sigio list for 1018 * the process or process group. 1019 */ 1020 int 1021 fsetown(pid_t pgid, struct sigio **sigiop) 1022 { 1023 struct proc *proc; 1024 struct pgrp *pgrp; 1025 struct sigio *sigio; 1026 int ret; 1027 1028 if (pgid == 0) { 1029 funsetown(sigiop); 1030 return (0); 1031 } 1032 1033 ret = 0; 1034 1035 /* Allocate and fill in the new sigio out of locks. */ 1036 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1037 sigio->sio_pgid = pgid; 1038 sigio->sio_ucred = crhold(curthread->td_ucred); 1039 sigio->sio_myref = sigiop; 1040 1041 sx_slock(&proctree_lock); 1042 if (pgid > 0) { 1043 proc = pfind(pgid); 1044 if (proc == NULL) { 1045 ret = ESRCH; 1046 goto fail; 1047 } 1048 1049 /* 1050 * Policy - Don't allow a process to FSETOWN a process 1051 * in another session. 1052 * 1053 * Remove this test to allow maximum flexibility or 1054 * restrict FSETOWN to the current process or process 1055 * group for maximum safety. 1056 */ 1057 PROC_UNLOCK(proc); 1058 if (proc->p_session != curthread->td_proc->p_session) { 1059 ret = EPERM; 1060 goto fail; 1061 } 1062 1063 pgrp = NULL; 1064 } else /* if (pgid < 0) */ { 1065 pgrp = pgfind(-pgid); 1066 if (pgrp == NULL) { 1067 ret = ESRCH; 1068 goto fail; 1069 } 1070 PGRP_UNLOCK(pgrp); 1071 1072 /* 1073 * Policy - Don't allow a process to FSETOWN a process 1074 * in another session. 1075 * 1076 * Remove this test to allow maximum flexibility or 1077 * restrict FSETOWN to the current process or process 1078 * group for maximum safety. 1079 */ 1080 if (pgrp->pg_session != curthread->td_proc->p_session) { 1081 ret = EPERM; 1082 goto fail; 1083 } 1084 1085 proc = NULL; 1086 } 1087 funsetown(sigiop); 1088 if (pgid > 0) { 1089 PROC_LOCK(proc); 1090 /* 1091 * Since funsetownlst() is called without the proctree 1092 * locked, we need to check for P_WEXIT. 1093 * XXX: is ESRCH correct? 1094 */ 1095 if ((proc->p_flag & P_WEXIT) != 0) { 1096 PROC_UNLOCK(proc); 1097 ret = ESRCH; 1098 goto fail; 1099 } 1100 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1101 sigio->sio_proc = proc; 1102 PROC_UNLOCK(proc); 1103 } else { 1104 PGRP_LOCK(pgrp); 1105 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1106 sigio->sio_pgrp = pgrp; 1107 PGRP_UNLOCK(pgrp); 1108 } 1109 sx_sunlock(&proctree_lock); 1110 SIGIO_LOCK(); 1111 *sigiop = sigio; 1112 SIGIO_UNLOCK(); 1113 return (0); 1114 1115 fail: 1116 sx_sunlock(&proctree_lock); 1117 crfree(sigio->sio_ucred); 1118 free(sigio, M_SIGIO); 1119 return (ret); 1120 } 1121 1122 /* 1123 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1124 */ 1125 pid_t 1126 fgetown(sigiop) 1127 struct sigio **sigiop; 1128 { 1129 pid_t pgid; 1130 1131 SIGIO_LOCK(); 1132 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1133 SIGIO_UNLOCK(); 1134 return (pgid); 1135 } 1136 1137 /* 1138 * Function drops the filedesc lock on return. 1139 */ 1140 static int 1141 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1142 int holdleaders) 1143 { 1144 int error; 1145 1146 FILEDESC_XLOCK_ASSERT(fdp); 1147 1148 if (holdleaders) { 1149 if (td->td_proc->p_fdtol != NULL) { 1150 /* 1151 * Ask fdfree() to sleep to ensure that all relevant 1152 * process leaders can be traversed in closef(). 1153 */ 1154 fdp->fd_holdleaderscount++; 1155 } else { 1156 holdleaders = 0; 1157 } 1158 } 1159 1160 /* 1161 * We now hold the fp reference that used to be owned by the 1162 * descriptor array. We have to unlock the FILEDESC *AFTER* 1163 * knote_fdclose to prevent a race of the fd getting opened, a knote 1164 * added, and deleteing a knote for the new fd. 1165 */ 1166 knote_fdclose(td, fd); 1167 1168 /* 1169 * We need to notify mqueue if the object is of type mqueue. 1170 */ 1171 if (fp->f_type == DTYPE_MQUEUE) 1172 mq_fdclose(td, fd, fp); 1173 FILEDESC_XUNLOCK(fdp); 1174 1175 error = closef(fp, td); 1176 if (holdleaders) { 1177 FILEDESC_XLOCK(fdp); 1178 fdp->fd_holdleaderscount--; 1179 if (fdp->fd_holdleaderscount == 0 && 1180 fdp->fd_holdleaderswakeup != 0) { 1181 fdp->fd_holdleaderswakeup = 0; 1182 wakeup(&fdp->fd_holdleaderscount); 1183 } 1184 FILEDESC_XUNLOCK(fdp); 1185 } 1186 return (error); 1187 } 1188 1189 /* 1190 * Close a file descriptor. 1191 */ 1192 #ifndef _SYS_SYSPROTO_H_ 1193 struct close_args { 1194 int fd; 1195 }; 1196 #endif 1197 /* ARGSUSED */ 1198 int 1199 sys_close(td, uap) 1200 struct thread *td; 1201 struct close_args *uap; 1202 { 1203 1204 return (kern_close(td, uap->fd)); 1205 } 1206 1207 int 1208 kern_close(td, fd) 1209 struct thread *td; 1210 int fd; 1211 { 1212 struct filedesc *fdp; 1213 struct file *fp; 1214 1215 fdp = td->td_proc->p_fd; 1216 1217 AUDIT_SYSCLOSE(td, fd); 1218 1219 FILEDESC_XLOCK(fdp); 1220 if ((fp = fget_locked(fdp, fd)) == NULL) { 1221 FILEDESC_XUNLOCK(fdp); 1222 return (EBADF); 1223 } 1224 fdfree(fdp, fd); 1225 1226 /* closefp() drops the FILEDESC lock for us. */ 1227 return (closefp(fdp, fd, fp, td, 1)); 1228 } 1229 1230 /* 1231 * Close open file descriptors. 1232 */ 1233 #ifndef _SYS_SYSPROTO_H_ 1234 struct closefrom_args { 1235 int lowfd; 1236 }; 1237 #endif 1238 /* ARGSUSED */ 1239 int 1240 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1241 { 1242 struct filedesc *fdp; 1243 int fd; 1244 1245 fdp = td->td_proc->p_fd; 1246 AUDIT_ARG_FD(uap->lowfd); 1247 1248 /* 1249 * Treat negative starting file descriptor values identical to 1250 * closefrom(0) which closes all files. 1251 */ 1252 if (uap->lowfd < 0) 1253 uap->lowfd = 0; 1254 FILEDESC_SLOCK(fdp); 1255 for (fd = uap->lowfd; fd <= fdp->fd_lastfile; fd++) { 1256 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1257 FILEDESC_SUNLOCK(fdp); 1258 (void)kern_close(td, fd); 1259 FILEDESC_SLOCK(fdp); 1260 } 1261 } 1262 FILEDESC_SUNLOCK(fdp); 1263 return (0); 1264 } 1265 1266 #if defined(COMPAT_43) 1267 /* 1268 * Return status information about a file descriptor. 1269 */ 1270 #ifndef _SYS_SYSPROTO_H_ 1271 struct ofstat_args { 1272 int fd; 1273 struct ostat *sb; 1274 }; 1275 #endif 1276 /* ARGSUSED */ 1277 int 1278 ofstat(struct thread *td, struct ofstat_args *uap) 1279 { 1280 struct ostat oub; 1281 struct stat ub; 1282 int error; 1283 1284 error = kern_fstat(td, uap->fd, &ub); 1285 if (error == 0) { 1286 cvtstat(&ub, &oub); 1287 error = copyout(&oub, uap->sb, sizeof(oub)); 1288 } 1289 return (error); 1290 } 1291 #endif /* COMPAT_43 */ 1292 1293 /* 1294 * Return status information about a file descriptor. 1295 */ 1296 #ifndef _SYS_SYSPROTO_H_ 1297 struct fstat_args { 1298 int fd; 1299 struct stat *sb; 1300 }; 1301 #endif 1302 /* ARGSUSED */ 1303 int 1304 sys_fstat(struct thread *td, struct fstat_args *uap) 1305 { 1306 struct stat ub; 1307 int error; 1308 1309 error = kern_fstat(td, uap->fd, &ub); 1310 if (error == 0) 1311 error = copyout(&ub, uap->sb, sizeof(ub)); 1312 return (error); 1313 } 1314 1315 int 1316 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1317 { 1318 struct file *fp; 1319 cap_rights_t rights; 1320 int error; 1321 1322 AUDIT_ARG_FD(fd); 1323 1324 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1325 if (error != 0) 1326 return (error); 1327 1328 AUDIT_ARG_FILE(td->td_proc, fp); 1329 1330 error = fo_stat(fp, sbp, td->td_ucred, td); 1331 fdrop(fp, td); 1332 #ifdef KTRACE 1333 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1334 ktrstat(sbp); 1335 #endif 1336 return (error); 1337 } 1338 1339 /* 1340 * Return status information about a file descriptor. 1341 */ 1342 #ifndef _SYS_SYSPROTO_H_ 1343 struct nfstat_args { 1344 int fd; 1345 struct nstat *sb; 1346 }; 1347 #endif 1348 /* ARGSUSED */ 1349 int 1350 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1351 { 1352 struct nstat nub; 1353 struct stat ub; 1354 int error; 1355 1356 error = kern_fstat(td, uap->fd, &ub); 1357 if (error == 0) { 1358 cvtnstat(&ub, &nub); 1359 error = copyout(&nub, uap->sb, sizeof(nub)); 1360 } 1361 return (error); 1362 } 1363 1364 /* 1365 * Return pathconf information about a file descriptor. 1366 */ 1367 #ifndef _SYS_SYSPROTO_H_ 1368 struct fpathconf_args { 1369 int fd; 1370 int name; 1371 }; 1372 #endif 1373 /* ARGSUSED */ 1374 int 1375 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1376 { 1377 struct file *fp; 1378 struct vnode *vp; 1379 cap_rights_t rights; 1380 int error; 1381 1382 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1383 if (error != 0) 1384 return (error); 1385 1386 /* If asynchronous I/O is available, it works for all descriptors. */ 1387 if (uap->name == _PC_ASYNC_IO) { 1388 td->td_retval[0] = async_io_version; 1389 goto out; 1390 } 1391 vp = fp->f_vnode; 1392 if (vp != NULL) { 1393 vn_lock(vp, LK_SHARED | LK_RETRY); 1394 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1395 VOP_UNLOCK(vp, 0); 1396 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1397 if (uap->name != _PC_PIPE_BUF) { 1398 error = EINVAL; 1399 } else { 1400 td->td_retval[0] = PIPE_BUF; 1401 error = 0; 1402 } 1403 } else { 1404 error = EOPNOTSUPP; 1405 } 1406 out: 1407 fdrop(fp, td); 1408 return (error); 1409 } 1410 1411 /* 1412 * Initialize filecaps structure. 1413 */ 1414 void 1415 filecaps_init(struct filecaps *fcaps) 1416 { 1417 1418 bzero(fcaps, sizeof(*fcaps)); 1419 fcaps->fc_nioctls = -1; 1420 } 1421 1422 /* 1423 * Copy filecaps structure allocating memory for ioctls array if needed. 1424 */ 1425 void 1426 filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1427 { 1428 size_t size; 1429 1430 *dst = *src; 1431 if (src->fc_ioctls != NULL) { 1432 KASSERT(src->fc_nioctls > 0, 1433 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1434 1435 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1436 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1437 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1438 } 1439 } 1440 1441 /* 1442 * Move filecaps structure to the new place and clear the old place. 1443 */ 1444 void 1445 filecaps_move(struct filecaps *src, struct filecaps *dst) 1446 { 1447 1448 *dst = *src; 1449 bzero(src, sizeof(*src)); 1450 } 1451 1452 /* 1453 * Fill the given filecaps structure with full rights. 1454 */ 1455 static void 1456 filecaps_fill(struct filecaps *fcaps) 1457 { 1458 1459 CAP_ALL(&fcaps->fc_rights); 1460 fcaps->fc_ioctls = NULL; 1461 fcaps->fc_nioctls = -1; 1462 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1463 } 1464 1465 /* 1466 * Free memory allocated within filecaps structure. 1467 */ 1468 void 1469 filecaps_free(struct filecaps *fcaps) 1470 { 1471 1472 free(fcaps->fc_ioctls, M_FILECAPS); 1473 bzero(fcaps, sizeof(*fcaps)); 1474 } 1475 1476 /* 1477 * Validate the given filecaps structure. 1478 */ 1479 static void 1480 filecaps_validate(const struct filecaps *fcaps, const char *func) 1481 { 1482 1483 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1484 ("%s: invalid rights", func)); 1485 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1486 ("%s: invalid fcntls", func)); 1487 KASSERT(fcaps->fc_fcntls == 0 || 1488 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1489 ("%s: fcntls without CAP_FCNTL", func)); 1490 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1491 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1492 ("%s: invalid ioctls", func)); 1493 KASSERT(fcaps->fc_nioctls == 0 || 1494 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1495 ("%s: ioctls without CAP_IOCTL", func)); 1496 } 1497 1498 static void 1499 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1500 { 1501 int nfd1; 1502 1503 FILEDESC_XLOCK_ASSERT(fdp); 1504 1505 nfd1 = fdp->fd_nfiles * 2; 1506 if (nfd1 < nfd) 1507 nfd1 = nfd; 1508 fdgrowtable(fdp, nfd1); 1509 } 1510 1511 /* 1512 * Grow the file table to accomodate (at least) nfd descriptors. 1513 */ 1514 static void 1515 fdgrowtable(struct filedesc *fdp, int nfd) 1516 { 1517 struct filedesc0 *fdp0; 1518 struct freetable *ft; 1519 struct filedescent *ntable; 1520 struct filedescent *otable; 1521 int nnfiles, onfiles; 1522 NDSLOTTYPE *nmap, *omap; 1523 1524 FILEDESC_XLOCK_ASSERT(fdp); 1525 1526 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1527 1528 /* save old values */ 1529 onfiles = fdp->fd_nfiles; 1530 otable = fdp->fd_ofiles; 1531 omap = fdp->fd_map; 1532 1533 /* compute the size of the new table */ 1534 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1535 if (nnfiles <= onfiles) 1536 /* the table is already large enough */ 1537 return; 1538 1539 /* 1540 * Allocate a new table. We need enough space for the 1541 * file entries themselves and the struct freetable we will use 1542 * when we decommission the table and place it on the freelist. 1543 * We place the struct freetable in the middle so we don't have 1544 * to worry about padding. 1545 */ 1546 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1547 M_FILEDESC, M_ZERO | M_WAITOK); 1548 /* copy the old data over and point at the new tables */ 1549 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1550 fdp->fd_ofiles = ntable; 1551 1552 /* 1553 * Allocate a new map only if the old is not large enough. It will 1554 * grow at a slower rate than the table as it can map more 1555 * entries than the table can hold. 1556 */ 1557 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1558 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1559 M_ZERO | M_WAITOK); 1560 /* copy over the old data and update the pointer */ 1561 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1562 fdp->fd_map = nmap; 1563 } 1564 1565 /* 1566 * In order to have a valid pattern for fget_unlocked() 1567 * fdp->fd_nfiles must be the last member to be updated, otherwise 1568 * fget_unlocked() consumers may reference a new, higher value for 1569 * fdp->fd_nfiles before to access the fdp->fd_ofiles array, 1570 * resulting in OOB accesses. 1571 */ 1572 atomic_store_rel_int(&fdp->fd_nfiles, nnfiles); 1573 1574 /* 1575 * Do not free the old file table, as some threads may still 1576 * reference entries within it. Instead, place it on a freelist 1577 * which will be processed when the struct filedesc is released. 1578 * 1579 * Note that if onfiles == NDFILE, we're dealing with the original 1580 * static allocation contained within (struct filedesc0 *)fdp, 1581 * which must not be freed. 1582 */ 1583 if (onfiles > NDFILE) { 1584 ft = (struct freetable *)&otable[onfiles]; 1585 fdp0 = (struct filedesc0 *)fdp; 1586 ft->ft_table = otable; 1587 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1588 } 1589 /* 1590 * The map does not have the same possibility of threads still 1591 * holding references to it. So always free it as long as it 1592 * does not reference the original static allocation. 1593 */ 1594 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1595 free(omap, M_FILEDESC); 1596 } 1597 1598 /* 1599 * Allocate a file descriptor for the process. 1600 */ 1601 int 1602 fdalloc(struct thread *td, int minfd, int *result) 1603 { 1604 struct proc *p = td->td_proc; 1605 struct filedesc *fdp = p->p_fd; 1606 int fd = -1, maxfd, allocfd; 1607 #ifdef RACCT 1608 int error; 1609 #endif 1610 1611 FILEDESC_XLOCK_ASSERT(fdp); 1612 1613 if (fdp->fd_freefile > minfd) 1614 minfd = fdp->fd_freefile; 1615 1616 maxfd = getmaxfd(p); 1617 1618 /* 1619 * Search the bitmap for a free descriptor starting at minfd. 1620 * If none is found, grow the file table. 1621 */ 1622 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1623 if (fd >= maxfd) 1624 return (EMFILE); 1625 if (fd >= fdp->fd_nfiles) { 1626 allocfd = min(fd * 2, maxfd); 1627 #ifdef RACCT 1628 PROC_LOCK(p); 1629 error = racct_set(p, RACCT_NOFILE, allocfd); 1630 PROC_UNLOCK(p); 1631 if (error != 0) 1632 return (EMFILE); 1633 #endif 1634 /* 1635 * fd is already equal to first free descriptor >= minfd, so 1636 * we only need to grow the table and we are done. 1637 */ 1638 fdgrowtable_exp(fdp, allocfd); 1639 } 1640 1641 /* 1642 * Perform some sanity checks, then mark the file descriptor as 1643 * used and return it to the caller. 1644 */ 1645 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1646 ("invalid descriptor %d", fd)); 1647 KASSERT(!fdisused(fdp, fd), 1648 ("fd_first_free() returned non-free descriptor")); 1649 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1650 ("file descriptor isn't free")); 1651 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1652 fdused(fdp, fd); 1653 *result = fd; 1654 return (0); 1655 } 1656 1657 /* 1658 * Allocate n file descriptors for the process. 1659 */ 1660 int 1661 fdallocn(struct thread *td, int minfd, int *fds, int n) 1662 { 1663 struct proc *p = td->td_proc; 1664 struct filedesc *fdp = p->p_fd; 1665 int i; 1666 1667 FILEDESC_XLOCK_ASSERT(fdp); 1668 1669 for (i = 0; i < n; i++) 1670 if (fdalloc(td, 0, &fds[i]) != 0) 1671 break; 1672 1673 if (i < n) { 1674 for (i--; i >= 0; i--) 1675 fdunused(fdp, fds[i]); 1676 return (EMFILE); 1677 } 1678 1679 return (0); 1680 } 1681 1682 /* 1683 * Create a new open file structure and allocate a file decriptor for the 1684 * process that refers to it. We add one reference to the file for the 1685 * descriptor table and one reference for resultfp. This is to prevent us 1686 * being preempted and the entry in the descriptor table closed after we 1687 * release the FILEDESC lock. 1688 */ 1689 int 1690 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1691 { 1692 struct file *fp; 1693 int error, fd; 1694 1695 error = falloc_noinstall(td, &fp); 1696 if (error) 1697 return (error); /* no reference held on error */ 1698 1699 error = finstall(td, fp, &fd, flags, NULL); 1700 if (error) { 1701 fdrop(fp, td); /* one reference (fp only) */ 1702 return (error); 1703 } 1704 1705 if (resultfp != NULL) 1706 *resultfp = fp; /* copy out result */ 1707 else 1708 fdrop(fp, td); /* release local reference */ 1709 1710 if (resultfd != NULL) 1711 *resultfd = fd; 1712 1713 return (0); 1714 } 1715 1716 /* 1717 * Create a new open file structure without allocating a file descriptor. 1718 */ 1719 int 1720 falloc_noinstall(struct thread *td, struct file **resultfp) 1721 { 1722 struct file *fp; 1723 int maxuserfiles = maxfiles - (maxfiles / 20); 1724 static struct timeval lastfail; 1725 static int curfail; 1726 1727 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1728 1729 if ((openfiles >= maxuserfiles && 1730 priv_check(td, PRIV_MAXFILES) != 0) || 1731 openfiles >= maxfiles) { 1732 if (ppsratecheck(&lastfail, &curfail, 1)) { 1733 printf("kern.maxfiles limit exceeded by uid %i, " 1734 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1735 } 1736 return (ENFILE); 1737 } 1738 atomic_add_int(&openfiles, 1); 1739 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1740 refcount_init(&fp->f_count, 1); 1741 fp->f_cred = crhold(td->td_ucred); 1742 fp->f_ops = &badfileops; 1743 fp->f_data = NULL; 1744 fp->f_vnode = NULL; 1745 *resultfp = fp; 1746 return (0); 1747 } 1748 1749 /* 1750 * Install a file in a file descriptor table. 1751 */ 1752 int 1753 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1754 struct filecaps *fcaps) 1755 { 1756 struct filedesc *fdp = td->td_proc->p_fd; 1757 struct filedescent *fde; 1758 int error; 1759 1760 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1761 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1762 if (fcaps != NULL) 1763 filecaps_validate(fcaps, __func__); 1764 1765 FILEDESC_XLOCK(fdp); 1766 if ((error = fdalloc(td, 0, fd))) { 1767 FILEDESC_XUNLOCK(fdp); 1768 return (error); 1769 } 1770 fhold(fp); 1771 fde = &fdp->fd_ofiles[*fd]; 1772 fde->fde_file = fp; 1773 if ((flags & O_CLOEXEC) != 0) 1774 fde->fde_flags |= UF_EXCLOSE; 1775 if (fcaps != NULL) 1776 filecaps_move(fcaps, &fde->fde_caps); 1777 else 1778 filecaps_fill(&fde->fde_caps); 1779 FILEDESC_XUNLOCK(fdp); 1780 return (0); 1781 } 1782 1783 /* 1784 * Build a new filedesc structure from another. 1785 * Copy the current, root, and jail root vnode references. 1786 */ 1787 struct filedesc * 1788 fdinit(struct filedesc *fdp) 1789 { 1790 struct filedesc0 *newfdp; 1791 1792 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1793 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1794 if (fdp != NULL) { 1795 FILEDESC_SLOCK(fdp); 1796 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1797 if (newfdp->fd_fd.fd_cdir) 1798 VREF(newfdp->fd_fd.fd_cdir); 1799 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1800 if (newfdp->fd_fd.fd_rdir) 1801 VREF(newfdp->fd_fd.fd_rdir); 1802 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1803 if (newfdp->fd_fd.fd_jdir) 1804 VREF(newfdp->fd_fd.fd_jdir); 1805 FILEDESC_SUNLOCK(fdp); 1806 } 1807 1808 /* Create the file descriptor table. */ 1809 newfdp->fd_fd.fd_refcnt = 1; 1810 newfdp->fd_fd.fd_holdcnt = 1; 1811 newfdp->fd_fd.fd_cmask = CMASK; 1812 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1813 newfdp->fd_fd.fd_nfiles = NDFILE; 1814 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1815 newfdp->fd_fd.fd_lastfile = -1; 1816 return (&newfdp->fd_fd); 1817 } 1818 1819 static struct filedesc * 1820 fdhold(struct proc *p) 1821 { 1822 struct filedesc *fdp; 1823 1824 mtx_lock(&fdesc_mtx); 1825 fdp = p->p_fd; 1826 if (fdp != NULL) 1827 fdp->fd_holdcnt++; 1828 mtx_unlock(&fdesc_mtx); 1829 return (fdp); 1830 } 1831 1832 static void 1833 fddrop(struct filedesc *fdp) 1834 { 1835 struct filedesc0 *fdp0; 1836 struct freetable *ft; 1837 int i; 1838 1839 mtx_lock(&fdesc_mtx); 1840 i = --fdp->fd_holdcnt; 1841 mtx_unlock(&fdesc_mtx); 1842 if (i > 0) 1843 return; 1844 1845 FILEDESC_LOCK_DESTROY(fdp); 1846 fdp0 = (struct filedesc0 *)fdp; 1847 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1848 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1849 free(ft->ft_table, M_FILEDESC); 1850 } 1851 free(fdp, M_FILEDESC); 1852 } 1853 1854 /* 1855 * Share a filedesc structure. 1856 */ 1857 struct filedesc * 1858 fdshare(struct filedesc *fdp) 1859 { 1860 1861 FILEDESC_XLOCK(fdp); 1862 fdp->fd_refcnt++; 1863 FILEDESC_XUNLOCK(fdp); 1864 return (fdp); 1865 } 1866 1867 /* 1868 * Unshare a filedesc structure, if necessary by making a copy 1869 */ 1870 void 1871 fdunshare(struct thread *td) 1872 { 1873 struct filedesc *tmp; 1874 struct proc *p = td->td_proc; 1875 1876 if (p->p_fd->fd_refcnt == 1) 1877 return; 1878 1879 tmp = fdcopy(p->p_fd); 1880 fdescfree(td); 1881 p->p_fd = tmp; 1882 } 1883 1884 /* 1885 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1886 * this is to ease callers, not catch errors. 1887 */ 1888 struct filedesc * 1889 fdcopy(struct filedesc *fdp) 1890 { 1891 struct filedesc *newfdp; 1892 struct filedescent *nfde, *ofde; 1893 int i; 1894 1895 /* Certain daemons might not have file descriptors. */ 1896 if (fdp == NULL) 1897 return (NULL); 1898 1899 newfdp = fdinit(fdp); 1900 FILEDESC_SLOCK(fdp); 1901 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1902 FILEDESC_SUNLOCK(fdp); 1903 FILEDESC_XLOCK(newfdp); 1904 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1905 FILEDESC_XUNLOCK(newfdp); 1906 FILEDESC_SLOCK(fdp); 1907 } 1908 /* copy all passable descriptors (i.e. not kqueue) */ 1909 newfdp->fd_freefile = -1; 1910 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1911 ofde = &fdp->fd_ofiles[i]; 1912 if (fdisused(fdp, i) && 1913 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1914 ofde->fde_file->f_ops != &badfileops) { 1915 nfde = &newfdp->fd_ofiles[i]; 1916 *nfde = *ofde; 1917 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1918 fhold(nfde->fde_file); 1919 newfdp->fd_lastfile = i; 1920 } else { 1921 if (newfdp->fd_freefile == -1) 1922 newfdp->fd_freefile = i; 1923 } 1924 } 1925 newfdp->fd_cmask = fdp->fd_cmask; 1926 FILEDESC_SUNLOCK(fdp); 1927 FILEDESC_XLOCK(newfdp); 1928 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1929 if (newfdp->fd_ofiles[i].fde_file != NULL) 1930 fdused(newfdp, i); 1931 } 1932 if (newfdp->fd_freefile == -1) 1933 newfdp->fd_freefile = i; 1934 FILEDESC_XUNLOCK(newfdp); 1935 return (newfdp); 1936 } 1937 1938 /* 1939 * Release a filedesc structure. 1940 */ 1941 void 1942 fdescfree(struct thread *td) 1943 { 1944 struct filedesc *fdp; 1945 int i; 1946 struct filedesc_to_leader *fdtol; 1947 struct file *fp; 1948 struct vnode *cdir, *jdir, *rdir, *vp; 1949 struct flock lf; 1950 1951 /* Certain daemons might not have file descriptors. */ 1952 fdp = td->td_proc->p_fd; 1953 if (fdp == NULL) 1954 return; 1955 1956 #ifdef RACCT 1957 PROC_LOCK(td->td_proc); 1958 racct_set(td->td_proc, RACCT_NOFILE, 0); 1959 PROC_UNLOCK(td->td_proc); 1960 #endif 1961 1962 /* Check for special need to clear POSIX style locks */ 1963 fdtol = td->td_proc->p_fdtol; 1964 if (fdtol != NULL) { 1965 FILEDESC_XLOCK(fdp); 1966 KASSERT(fdtol->fdl_refcount > 0, 1967 ("filedesc_to_refcount botch: fdl_refcount=%d", 1968 fdtol->fdl_refcount)); 1969 if (fdtol->fdl_refcount == 1 && 1970 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1971 for (i = 0; i <= fdp->fd_lastfile; i++) { 1972 fp = fdp->fd_ofiles[i].fde_file; 1973 if (fp == NULL || fp->f_type != DTYPE_VNODE) 1974 continue; 1975 fhold(fp); 1976 FILEDESC_XUNLOCK(fdp); 1977 lf.l_whence = SEEK_SET; 1978 lf.l_start = 0; 1979 lf.l_len = 0; 1980 lf.l_type = F_UNLCK; 1981 vp = fp->f_vnode; 1982 (void) VOP_ADVLOCK(vp, 1983 (caddr_t)td->td_proc->p_leader, F_UNLCK, 1984 &lf, F_POSIX); 1985 FILEDESC_XLOCK(fdp); 1986 fdrop(fp, td); 1987 } 1988 } 1989 retry: 1990 if (fdtol->fdl_refcount == 1) { 1991 if (fdp->fd_holdleaderscount > 0 && 1992 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1993 /* 1994 * close() or do_dup() has cleared a reference 1995 * in a shared file descriptor table. 1996 */ 1997 fdp->fd_holdleaderswakeup = 1; 1998 sx_sleep(&fdp->fd_holdleaderscount, 1999 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2000 goto retry; 2001 } 2002 if (fdtol->fdl_holdcount > 0) { 2003 /* 2004 * Ensure that fdtol->fdl_leader remains 2005 * valid in closef(). 2006 */ 2007 fdtol->fdl_wakeup = 1; 2008 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2009 "fdlhold", 0); 2010 goto retry; 2011 } 2012 } 2013 fdtol->fdl_refcount--; 2014 if (fdtol->fdl_refcount == 0 && 2015 fdtol->fdl_holdcount == 0) { 2016 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2017 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2018 } else 2019 fdtol = NULL; 2020 td->td_proc->p_fdtol = NULL; 2021 FILEDESC_XUNLOCK(fdp); 2022 if (fdtol != NULL) 2023 free(fdtol, M_FILEDESC_TO_LEADER); 2024 } 2025 2026 mtx_lock(&fdesc_mtx); 2027 td->td_proc->p_fd = NULL; 2028 mtx_unlock(&fdesc_mtx); 2029 2030 FILEDESC_XLOCK(fdp); 2031 i = --fdp->fd_refcnt; 2032 if (i > 0) { 2033 FILEDESC_XUNLOCK(fdp); 2034 return; 2035 } 2036 2037 cdir = fdp->fd_cdir; 2038 fdp->fd_cdir = NULL; 2039 rdir = fdp->fd_rdir; 2040 fdp->fd_rdir = NULL; 2041 jdir = fdp->fd_jdir; 2042 fdp->fd_jdir = NULL; 2043 FILEDESC_XUNLOCK(fdp); 2044 2045 for (i = 0; i <= fdp->fd_lastfile; i++) { 2046 fp = fdp->fd_ofiles[i].fde_file; 2047 if (fp != NULL) { 2048 fdfree_last(fdp, i); 2049 (void) closef(fp, td); 2050 } 2051 } 2052 2053 if (fdp->fd_nfiles > NDFILE) 2054 free(fdp->fd_ofiles, M_FILEDESC); 2055 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2056 free(fdp->fd_map, M_FILEDESC); 2057 2058 if (cdir != NULL) 2059 vrele(cdir); 2060 if (rdir != NULL) 2061 vrele(rdir); 2062 if (jdir != NULL) 2063 vrele(jdir); 2064 2065 fddrop(fdp); 2066 } 2067 2068 /* 2069 * For setugid programs, we don't want to people to use that setugidness 2070 * to generate error messages which write to a file which otherwise would 2071 * otherwise be off-limits to the process. We check for filesystems where 2072 * the vnode can change out from under us after execve (like [lin]procfs). 2073 * 2074 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2075 * sufficient. We also don't check for setugidness since we know we are. 2076 */ 2077 static int 2078 is_unsafe(struct file *fp) 2079 { 2080 if (fp->f_type == DTYPE_VNODE) { 2081 struct vnode *vp = fp->f_vnode; 2082 2083 if ((vp->v_vflag & VV_PROCDEP) != 0) 2084 return (1); 2085 } 2086 return (0); 2087 } 2088 2089 /* 2090 * Make this setguid thing safe, if at all possible. 2091 */ 2092 void 2093 setugidsafety(struct thread *td) 2094 { 2095 struct filedesc *fdp; 2096 struct file *fp; 2097 int i; 2098 2099 fdp = td->td_proc->p_fd; 2100 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2101 FILEDESC_XLOCK(fdp); 2102 for (i = 0; i <= fdp->fd_lastfile; i++) { 2103 if (i > 2) 2104 break; 2105 fp = fdp->fd_ofiles[i].fde_file; 2106 if (fp != NULL && is_unsafe(fp)) { 2107 knote_fdclose(td, i); 2108 /* 2109 * NULL-out descriptor prior to close to avoid 2110 * a race while close blocks. 2111 */ 2112 fdfree(fdp, i); 2113 FILEDESC_XUNLOCK(fdp); 2114 (void) closef(fp, td); 2115 FILEDESC_XLOCK(fdp); 2116 } 2117 } 2118 FILEDESC_XUNLOCK(fdp); 2119 } 2120 2121 /* 2122 * If a specific file object occupies a specific file descriptor, close the 2123 * file descriptor entry and drop a reference on the file object. This is a 2124 * convenience function to handle a subsequent error in a function that calls 2125 * falloc() that handles the race that another thread might have closed the 2126 * file descriptor out from under the thread creating the file object. 2127 */ 2128 void 2129 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2130 { 2131 2132 FILEDESC_XLOCK(fdp); 2133 if (fdp->fd_ofiles[idx].fde_file == fp) { 2134 fdfree(fdp, idx); 2135 FILEDESC_XUNLOCK(fdp); 2136 fdrop(fp, td); 2137 } else 2138 FILEDESC_XUNLOCK(fdp); 2139 } 2140 2141 /* 2142 * Close any files on exec? 2143 */ 2144 void 2145 fdcloseexec(struct thread *td) 2146 { 2147 struct filedesc *fdp; 2148 struct filedescent *fde; 2149 struct file *fp; 2150 int i; 2151 2152 fdp = td->td_proc->p_fd; 2153 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2154 FILEDESC_XLOCK(fdp); 2155 for (i = 0; i <= fdp->fd_lastfile; i++) { 2156 fde = &fdp->fd_ofiles[i]; 2157 fp = fde->fde_file; 2158 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2159 (fde->fde_flags & UF_EXCLOSE))) { 2160 fdfree(fdp, i); 2161 (void) closefp(fdp, i, fp, td, 0); 2162 /* closefp() drops the FILEDESC lock. */ 2163 FILEDESC_XLOCK(fdp); 2164 } 2165 } 2166 FILEDESC_XUNLOCK(fdp); 2167 } 2168 2169 /* 2170 * It is unsafe for set[ug]id processes to be started with file 2171 * descriptors 0..2 closed, as these descriptors are given implicit 2172 * significance in the Standard C library. fdcheckstd() will create a 2173 * descriptor referencing /dev/null for each of stdin, stdout, and 2174 * stderr that is not already open. 2175 */ 2176 int 2177 fdcheckstd(struct thread *td) 2178 { 2179 struct filedesc *fdp; 2180 register_t retval, save; 2181 int i, error, devnull; 2182 2183 fdp = td->td_proc->p_fd; 2184 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2185 devnull = -1; 2186 error = 0; 2187 for (i = 0; i < 3; i++) { 2188 if (fdp->fd_ofiles[i].fde_file != NULL) 2189 continue; 2190 if (devnull < 0) { 2191 save = td->td_retval[0]; 2192 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2193 O_RDWR, 0); 2194 devnull = td->td_retval[0]; 2195 td->td_retval[0] = save; 2196 if (error) 2197 break; 2198 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2199 } else { 2200 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2201 if (error != 0) 2202 break; 2203 } 2204 } 2205 return (error); 2206 } 2207 2208 /* 2209 * Internal form of close. Decrement reference count on file structure. 2210 * Note: td may be NULL when closing a file that was being passed in a 2211 * message. 2212 * 2213 * XXXRW: Giant is not required for the caller, but often will be held; this 2214 * makes it moderately likely the Giant will be recursed in the VFS case. 2215 */ 2216 int 2217 closef(struct file *fp, struct thread *td) 2218 { 2219 struct vnode *vp; 2220 struct flock lf; 2221 struct filedesc_to_leader *fdtol; 2222 struct filedesc *fdp; 2223 2224 /* 2225 * POSIX record locking dictates that any close releases ALL 2226 * locks owned by this process. This is handled by setting 2227 * a flag in the unlock to free ONLY locks obeying POSIX 2228 * semantics, and not to free BSD-style file locks. 2229 * If the descriptor was in a message, POSIX-style locks 2230 * aren't passed with the descriptor, and the thread pointer 2231 * will be NULL. Callers should be careful only to pass a 2232 * NULL thread pointer when there really is no owning 2233 * context that might have locks, or the locks will be 2234 * leaked. 2235 */ 2236 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2237 vp = fp->f_vnode; 2238 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2239 lf.l_whence = SEEK_SET; 2240 lf.l_start = 0; 2241 lf.l_len = 0; 2242 lf.l_type = F_UNLCK; 2243 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2244 F_UNLCK, &lf, F_POSIX); 2245 } 2246 fdtol = td->td_proc->p_fdtol; 2247 if (fdtol != NULL) { 2248 /* 2249 * Handle special case where file descriptor table is 2250 * shared between multiple process leaders. 2251 */ 2252 fdp = td->td_proc->p_fd; 2253 FILEDESC_XLOCK(fdp); 2254 for (fdtol = fdtol->fdl_next; 2255 fdtol != td->td_proc->p_fdtol; 2256 fdtol = fdtol->fdl_next) { 2257 if ((fdtol->fdl_leader->p_flag & 2258 P_ADVLOCK) == 0) 2259 continue; 2260 fdtol->fdl_holdcount++; 2261 FILEDESC_XUNLOCK(fdp); 2262 lf.l_whence = SEEK_SET; 2263 lf.l_start = 0; 2264 lf.l_len = 0; 2265 lf.l_type = F_UNLCK; 2266 vp = fp->f_vnode; 2267 (void) VOP_ADVLOCK(vp, 2268 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2269 F_POSIX); 2270 FILEDESC_XLOCK(fdp); 2271 fdtol->fdl_holdcount--; 2272 if (fdtol->fdl_holdcount == 0 && 2273 fdtol->fdl_wakeup != 0) { 2274 fdtol->fdl_wakeup = 0; 2275 wakeup(fdtol); 2276 } 2277 } 2278 FILEDESC_XUNLOCK(fdp); 2279 } 2280 } 2281 return (fdrop(fp, td)); 2282 } 2283 2284 /* 2285 * Initialize the file pointer with the specified properties. 2286 * 2287 * The ops are set with release semantics to be certain that the flags, type, 2288 * and data are visible when ops is. This is to prevent ops methods from being 2289 * called with bad data. 2290 */ 2291 void 2292 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2293 { 2294 fp->f_data = data; 2295 fp->f_flag = flag; 2296 fp->f_type = type; 2297 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2298 } 2299 2300 int 2301 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2302 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2303 { 2304 #ifdef CAPABILITIES 2305 struct filedescent fde; 2306 #endif 2307 struct file *fp; 2308 u_int count; 2309 #ifdef CAPABILITIES 2310 cap_rights_t haverights; 2311 int error; 2312 #endif 2313 2314 /* 2315 * Avoid reads reordering and then a first access to the 2316 * fdp->fd_ofiles table which could result in OOB operation. 2317 */ 2318 if (fd < 0 || fd >= atomic_load_acq_int(&fdp->fd_nfiles)) 2319 return (EBADF); 2320 /* 2321 * Fetch the descriptor locklessly. We avoid fdrop() races by 2322 * never raising a refcount above 0. To accomplish this we have 2323 * to use a cmpset loop rather than an atomic_add. The descriptor 2324 * must be re-verified once we acquire a reference to be certain 2325 * that the identity is still correct and we did not lose a race 2326 * due to preemption. 2327 */ 2328 for (;;) { 2329 #ifdef CAPABILITIES 2330 fde = fdp->fd_ofiles[fd]; 2331 fp = fde.fde_file; 2332 #else 2333 fp = fdp->fd_ofiles[fd].fde_file; 2334 #endif 2335 if (fp == NULL) 2336 return (EBADF); 2337 #ifdef CAPABILITIES 2338 haverights = *cap_rights_fde(&fde); 2339 if (needrightsp != NULL) { 2340 error = cap_check(&haverights, needrightsp); 2341 if (error != 0) 2342 return (error); 2343 if (cap_rights_is_set(needrightsp, CAP_FCNTL)) { 2344 error = cap_fcntl_check_fde(&fde, needfcntl); 2345 if (error != 0) 2346 return (error); 2347 } 2348 } 2349 #endif 2350 count = fp->f_count; 2351 if (count == 0) 2352 continue; 2353 /* 2354 * Use an acquire barrier to prevent caching of fd_ofiles 2355 * so it is refreshed for verification. 2356 */ 2357 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2358 continue; 2359 if (fp == fdp->fd_ofiles[fd].fde_file) 2360 break; 2361 fdrop(fp, curthread); 2362 } 2363 *fpp = fp; 2364 if (haverightsp != NULL) { 2365 #ifdef CAPABILITIES 2366 *haverightsp = haverights; 2367 #else 2368 CAP_ALL(haverightsp); 2369 #endif 2370 } 2371 return (0); 2372 } 2373 2374 /* 2375 * Extract the file pointer associated with the specified descriptor for the 2376 * current user process. 2377 * 2378 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2379 * returned. 2380 * 2381 * File's rights will be checked against the capability rights mask. 2382 * 2383 * If an error occured the non-zero error is returned and *fpp is set to 2384 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2385 * responsible for fdrop(). 2386 */ 2387 static __inline int 2388 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2389 cap_rights_t *needrightsp, u_char *maxprotp) 2390 { 2391 struct filedesc *fdp; 2392 struct file *fp; 2393 cap_rights_t haverights, needrights; 2394 int error; 2395 2396 *fpp = NULL; 2397 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2398 return (EBADF); 2399 if (needrightsp != NULL) 2400 needrights = *needrightsp; 2401 else 2402 cap_rights_init(&needrights); 2403 if (maxprotp != NULL) 2404 cap_rights_set(&needrights, CAP_MMAP); 2405 error = fget_unlocked(fdp, fd, &needrights, 0, &fp, &haverights); 2406 if (error != 0) 2407 return (error); 2408 if (fp->f_ops == &badfileops) { 2409 fdrop(fp, td); 2410 return (EBADF); 2411 } 2412 2413 #ifdef CAPABILITIES 2414 /* 2415 * If requested, convert capability rights to access flags. 2416 */ 2417 if (maxprotp != NULL) 2418 *maxprotp = cap_rights_to_vmprot(&haverights); 2419 #else /* !CAPABILITIES */ 2420 if (maxprotp != NULL) 2421 *maxprotp = VM_PROT_ALL; 2422 #endif /* CAPABILITIES */ 2423 2424 /* 2425 * FREAD and FWRITE failure return EBADF as per POSIX. 2426 */ 2427 error = 0; 2428 switch (flags) { 2429 case FREAD: 2430 case FWRITE: 2431 if ((fp->f_flag & flags) == 0) 2432 error = EBADF; 2433 break; 2434 case FEXEC: 2435 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2436 ((fp->f_flag & FWRITE) != 0)) 2437 error = EBADF; 2438 break; 2439 case 0: 2440 break; 2441 default: 2442 KASSERT(0, ("wrong flags")); 2443 } 2444 2445 if (error != 0) { 2446 fdrop(fp, td); 2447 return (error); 2448 } 2449 2450 *fpp = fp; 2451 return (0); 2452 } 2453 2454 int 2455 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2456 { 2457 2458 return(_fget(td, fd, fpp, 0, rightsp, NULL)); 2459 } 2460 2461 int 2462 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2463 struct file **fpp) 2464 { 2465 2466 return (_fget(td, fd, fpp, 0, rightsp, maxprotp)); 2467 } 2468 2469 int 2470 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2471 { 2472 2473 return(_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2474 } 2475 2476 int 2477 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2478 { 2479 2480 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2481 } 2482 2483 /* 2484 * Like fget() but loads the underlying vnode, or returns an error if the 2485 * descriptor does not represent a vnode. Note that pipes use vnodes but 2486 * never have VM objects. The returned vnode will be vref()'d. 2487 * 2488 * XXX: what about the unused flags ? 2489 */ 2490 static __inline int 2491 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2492 struct vnode **vpp) 2493 { 2494 struct file *fp; 2495 int error; 2496 2497 *vpp = NULL; 2498 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2499 if (error != 0) 2500 return (error); 2501 if (fp->f_vnode == NULL) { 2502 error = EINVAL; 2503 } else { 2504 *vpp = fp->f_vnode; 2505 vref(*vpp); 2506 } 2507 fdrop(fp, td); 2508 2509 return (error); 2510 } 2511 2512 int 2513 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2514 { 2515 2516 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2517 } 2518 2519 int 2520 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2521 struct filecaps *havecaps, struct vnode **vpp) 2522 { 2523 struct filedesc *fdp; 2524 struct file *fp; 2525 #ifdef CAPABILITIES 2526 int error; 2527 #endif 2528 2529 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2530 return (EBADF); 2531 2532 fp = fget_locked(fdp, fd); 2533 if (fp == NULL || fp->f_ops == &badfileops) 2534 return (EBADF); 2535 2536 #ifdef CAPABILITIES 2537 if (needrightsp != NULL) { 2538 error = cap_check(cap_rights(fdp, fd), needrightsp); 2539 if (error != 0) 2540 return (error); 2541 } 2542 #endif 2543 2544 if (fp->f_vnode == NULL) 2545 return (EINVAL); 2546 2547 *vpp = fp->f_vnode; 2548 vref(*vpp); 2549 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2550 2551 return (0); 2552 } 2553 2554 int 2555 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2556 { 2557 2558 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2559 } 2560 2561 int 2562 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2563 { 2564 2565 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2566 } 2567 2568 #ifdef notyet 2569 int 2570 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2571 struct vnode **vpp) 2572 { 2573 2574 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2575 } 2576 #endif 2577 2578 /* 2579 * Like fget() but loads the underlying socket, or returns an error if the 2580 * descriptor does not represent a socket. 2581 * 2582 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2583 * in the future. 2584 * 2585 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2586 * on their file descriptor reference to prevent the socket from being free'd 2587 * during use. 2588 */ 2589 int 2590 fgetsock(struct thread *td, int fd, cap_rights_t *rightsp, struct socket **spp, 2591 u_int *fflagp) 2592 { 2593 struct file *fp; 2594 int error; 2595 2596 *spp = NULL; 2597 if (fflagp != NULL) 2598 *fflagp = 0; 2599 if ((error = _fget(td, fd, &fp, 0, rightsp, NULL)) != 0) 2600 return (error); 2601 if (fp->f_type != DTYPE_SOCKET) { 2602 error = ENOTSOCK; 2603 } else { 2604 *spp = fp->f_data; 2605 if (fflagp) 2606 *fflagp = fp->f_flag; 2607 SOCK_LOCK(*spp); 2608 soref(*spp); 2609 SOCK_UNLOCK(*spp); 2610 } 2611 fdrop(fp, td); 2612 2613 return (error); 2614 } 2615 2616 /* 2617 * Drop the reference count on the socket and XXX release the SX lock in the 2618 * future. The last reference closes the socket. 2619 * 2620 * Note: fputsock() is deprecated, see comment for fgetsock(). 2621 */ 2622 void 2623 fputsock(struct socket *so) 2624 { 2625 2626 ACCEPT_LOCK(); 2627 SOCK_LOCK(so); 2628 CURVNET_SET(so->so_vnet); 2629 sorele(so); 2630 CURVNET_RESTORE(); 2631 } 2632 2633 /* 2634 * Handle the last reference to a file being closed. 2635 */ 2636 int 2637 _fdrop(struct file *fp, struct thread *td) 2638 { 2639 int error; 2640 2641 error = 0; 2642 if (fp->f_count != 0) 2643 panic("fdrop: count %d", fp->f_count); 2644 if (fp->f_ops != &badfileops) 2645 error = fo_close(fp, td); 2646 atomic_subtract_int(&openfiles, 1); 2647 crfree(fp->f_cred); 2648 free(fp->f_advice, M_FADVISE); 2649 uma_zfree(file_zone, fp); 2650 2651 return (error); 2652 } 2653 2654 /* 2655 * Apply an advisory lock on a file descriptor. 2656 * 2657 * Just attempt to get a record lock of the requested type on the entire file 2658 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2659 */ 2660 #ifndef _SYS_SYSPROTO_H_ 2661 struct flock_args { 2662 int fd; 2663 int how; 2664 }; 2665 #endif 2666 /* ARGSUSED */ 2667 int 2668 sys_flock(struct thread *td, struct flock_args *uap) 2669 { 2670 struct file *fp; 2671 struct vnode *vp; 2672 struct flock lf; 2673 cap_rights_t rights; 2674 int error; 2675 2676 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2677 if (error != 0) 2678 return (error); 2679 if (fp->f_type != DTYPE_VNODE) { 2680 fdrop(fp, td); 2681 return (EOPNOTSUPP); 2682 } 2683 2684 vp = fp->f_vnode; 2685 lf.l_whence = SEEK_SET; 2686 lf.l_start = 0; 2687 lf.l_len = 0; 2688 if (uap->how & LOCK_UN) { 2689 lf.l_type = F_UNLCK; 2690 atomic_clear_int(&fp->f_flag, FHASLOCK); 2691 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2692 goto done2; 2693 } 2694 if (uap->how & LOCK_EX) 2695 lf.l_type = F_WRLCK; 2696 else if (uap->how & LOCK_SH) 2697 lf.l_type = F_RDLCK; 2698 else { 2699 error = EBADF; 2700 goto done2; 2701 } 2702 atomic_set_int(&fp->f_flag, FHASLOCK); 2703 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2704 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2705 done2: 2706 fdrop(fp, td); 2707 return (error); 2708 } 2709 /* 2710 * Duplicate the specified descriptor to a free descriptor. 2711 */ 2712 int 2713 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2714 int openerror, int *indxp) 2715 { 2716 struct file *fp; 2717 int error, indx; 2718 2719 KASSERT(openerror == ENODEV || openerror == ENXIO, 2720 ("unexpected error %d in %s", openerror, __func__)); 2721 2722 /* 2723 * If the to-be-dup'd fd number is greater than the allowed number 2724 * of file descriptors, or the fd to be dup'd has already been 2725 * closed, then reject. 2726 */ 2727 FILEDESC_XLOCK(fdp); 2728 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2729 FILEDESC_XUNLOCK(fdp); 2730 return (EBADF); 2731 } 2732 2733 error = fdalloc(td, 0, &indx); 2734 if (error != 0) { 2735 FILEDESC_XUNLOCK(fdp); 2736 return (error); 2737 } 2738 2739 /* 2740 * There are two cases of interest here. 2741 * 2742 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2743 * 2744 * For ENXIO steal away the file structure from (dfd) and store it in 2745 * (indx). (dfd) is effectively closed by this operation. 2746 */ 2747 switch (openerror) { 2748 case ENODEV: 2749 /* 2750 * Check that the mode the file is being opened for is a 2751 * subset of the mode of the existing descriptor. 2752 */ 2753 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2754 fdunused(fdp, indx); 2755 FILEDESC_XUNLOCK(fdp); 2756 return (EACCES); 2757 } 2758 fhold(fp); 2759 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2760 filecaps_copy(&fdp->fd_ofiles[dfd].fde_caps, 2761 &fdp->fd_ofiles[indx].fde_caps); 2762 break; 2763 case ENXIO: 2764 /* 2765 * Steal away the file pointer from dfd and stuff it into indx. 2766 */ 2767 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2768 bzero(&fdp->fd_ofiles[dfd], sizeof(fdp->fd_ofiles[dfd])); 2769 fdunused(fdp, dfd); 2770 break; 2771 } 2772 FILEDESC_XUNLOCK(fdp); 2773 *indxp = indx; 2774 return (0); 2775 } 2776 2777 /* 2778 * Scan all active processes and prisons to see if any of them have a current 2779 * or root directory of `olddp'. If so, replace them with the new mount point. 2780 */ 2781 void 2782 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2783 { 2784 struct filedesc *fdp; 2785 struct prison *pr; 2786 struct proc *p; 2787 int nrele; 2788 2789 if (vrefcnt(olddp) == 1) 2790 return; 2791 nrele = 0; 2792 sx_slock(&allproc_lock); 2793 FOREACH_PROC_IN_SYSTEM(p) { 2794 fdp = fdhold(p); 2795 if (fdp == NULL) 2796 continue; 2797 FILEDESC_XLOCK(fdp); 2798 if (fdp->fd_cdir == olddp) { 2799 vref(newdp); 2800 fdp->fd_cdir = newdp; 2801 nrele++; 2802 } 2803 if (fdp->fd_rdir == olddp) { 2804 vref(newdp); 2805 fdp->fd_rdir = newdp; 2806 nrele++; 2807 } 2808 if (fdp->fd_jdir == olddp) { 2809 vref(newdp); 2810 fdp->fd_jdir = newdp; 2811 nrele++; 2812 } 2813 FILEDESC_XUNLOCK(fdp); 2814 fddrop(fdp); 2815 } 2816 sx_sunlock(&allproc_lock); 2817 if (rootvnode == olddp) { 2818 vref(newdp); 2819 rootvnode = newdp; 2820 nrele++; 2821 } 2822 mtx_lock(&prison0.pr_mtx); 2823 if (prison0.pr_root == olddp) { 2824 vref(newdp); 2825 prison0.pr_root = newdp; 2826 nrele++; 2827 } 2828 mtx_unlock(&prison0.pr_mtx); 2829 sx_slock(&allprison_lock); 2830 TAILQ_FOREACH(pr, &allprison, pr_list) { 2831 mtx_lock(&pr->pr_mtx); 2832 if (pr->pr_root == olddp) { 2833 vref(newdp); 2834 pr->pr_root = newdp; 2835 nrele++; 2836 } 2837 mtx_unlock(&pr->pr_mtx); 2838 } 2839 sx_sunlock(&allprison_lock); 2840 while (nrele--) 2841 vrele(olddp); 2842 } 2843 2844 struct filedesc_to_leader * 2845 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2846 { 2847 struct filedesc_to_leader *fdtol; 2848 2849 fdtol = malloc(sizeof(struct filedesc_to_leader), 2850 M_FILEDESC_TO_LEADER, 2851 M_WAITOK); 2852 fdtol->fdl_refcount = 1; 2853 fdtol->fdl_holdcount = 0; 2854 fdtol->fdl_wakeup = 0; 2855 fdtol->fdl_leader = leader; 2856 if (old != NULL) { 2857 FILEDESC_XLOCK(fdp); 2858 fdtol->fdl_next = old->fdl_next; 2859 fdtol->fdl_prev = old; 2860 old->fdl_next = fdtol; 2861 fdtol->fdl_next->fdl_prev = fdtol; 2862 FILEDESC_XUNLOCK(fdp); 2863 } else { 2864 fdtol->fdl_next = fdtol; 2865 fdtol->fdl_prev = fdtol; 2866 } 2867 return (fdtol); 2868 } 2869 2870 /* 2871 * Get file structures globally. 2872 */ 2873 static int 2874 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2875 { 2876 struct xfile xf; 2877 struct filedesc *fdp; 2878 struct file *fp; 2879 struct proc *p; 2880 int error, n; 2881 2882 error = sysctl_wire_old_buffer(req, 0); 2883 if (error != 0) 2884 return (error); 2885 if (req->oldptr == NULL) { 2886 n = 0; 2887 sx_slock(&allproc_lock); 2888 FOREACH_PROC_IN_SYSTEM(p) { 2889 if (p->p_state == PRS_NEW) 2890 continue; 2891 fdp = fdhold(p); 2892 if (fdp == NULL) 2893 continue; 2894 /* overestimates sparse tables. */ 2895 if (fdp->fd_lastfile > 0) 2896 n += fdp->fd_lastfile; 2897 fddrop(fdp); 2898 } 2899 sx_sunlock(&allproc_lock); 2900 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2901 } 2902 error = 0; 2903 bzero(&xf, sizeof(xf)); 2904 xf.xf_size = sizeof(xf); 2905 sx_slock(&allproc_lock); 2906 FOREACH_PROC_IN_SYSTEM(p) { 2907 PROC_LOCK(p); 2908 if (p->p_state == PRS_NEW) { 2909 PROC_UNLOCK(p); 2910 continue; 2911 } 2912 if (p_cansee(req->td, p) != 0) { 2913 PROC_UNLOCK(p); 2914 continue; 2915 } 2916 xf.xf_pid = p->p_pid; 2917 xf.xf_uid = p->p_ucred->cr_uid; 2918 PROC_UNLOCK(p); 2919 fdp = fdhold(p); 2920 if (fdp == NULL) 2921 continue; 2922 FILEDESC_SLOCK(fdp); 2923 for (n = 0; fdp->fd_refcnt > 0 && n <= fdp->fd_lastfile; ++n) { 2924 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 2925 continue; 2926 xf.xf_fd = n; 2927 xf.xf_file = fp; 2928 xf.xf_data = fp->f_data; 2929 xf.xf_vnode = fp->f_vnode; 2930 xf.xf_type = fp->f_type; 2931 xf.xf_count = fp->f_count; 2932 xf.xf_msgcount = 0; 2933 xf.xf_offset = foffset_get(fp); 2934 xf.xf_flag = fp->f_flag; 2935 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2936 if (error) 2937 break; 2938 } 2939 FILEDESC_SUNLOCK(fdp); 2940 fddrop(fdp); 2941 if (error) 2942 break; 2943 } 2944 sx_sunlock(&allproc_lock); 2945 return (error); 2946 } 2947 2948 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 2949 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2950 2951 #ifdef KINFO_OFILE_SIZE 2952 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 2953 #endif 2954 2955 #ifdef COMPAT_FREEBSD7 2956 static int 2957 export_vnode_for_osysctl(struct vnode *vp, int type, 2958 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 2959 { 2960 int error; 2961 char *fullpath, *freepath; 2962 2963 bzero(kif, sizeof(*kif)); 2964 kif->kf_structsize = sizeof(*kif); 2965 2966 vref(vp); 2967 kif->kf_fd = type; 2968 kif->kf_type = KF_TYPE_VNODE; 2969 /* This function only handles directories. */ 2970 if (vp->v_type != VDIR) { 2971 vrele(vp); 2972 return (ENOTDIR); 2973 } 2974 kif->kf_vnode_type = KF_VTYPE_VDIR; 2975 2976 /* 2977 * This is not a true file descriptor, so we set a bogus refcount 2978 * and offset to indicate these fields should be ignored. 2979 */ 2980 kif->kf_ref_count = -1; 2981 kif->kf_offset = -1; 2982 2983 freepath = NULL; 2984 fullpath = "-"; 2985 FILEDESC_SUNLOCK(fdp); 2986 vn_fullpath(curthread, vp, &fullpath, &freepath); 2987 vrele(vp); 2988 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 2989 if (freepath != NULL) 2990 free(freepath, M_TEMP); 2991 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 2992 FILEDESC_SLOCK(fdp); 2993 return (error); 2994 } 2995 2996 /* 2997 * Get per-process file descriptors for use by procstat(1), et al. 2998 */ 2999 static int 3000 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3001 { 3002 char *fullpath, *freepath; 3003 struct kinfo_ofile *kif; 3004 struct filedesc *fdp; 3005 int error, i, *name; 3006 struct shmfd *shmfd; 3007 struct socket *so; 3008 struct vnode *vp; 3009 struct ksem *ks; 3010 struct file *fp; 3011 struct proc *p; 3012 struct tty *tp; 3013 3014 name = (int *)arg1; 3015 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3016 if (error != 0) 3017 return (error); 3018 fdp = fdhold(p); 3019 PROC_UNLOCK(p); 3020 if (fdp == NULL) 3021 return (ENOENT); 3022 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3023 FILEDESC_SLOCK(fdp); 3024 if (fdp->fd_cdir != NULL) 3025 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3026 fdp, req); 3027 if (fdp->fd_rdir != NULL) 3028 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3029 fdp, req); 3030 if (fdp->fd_jdir != NULL) 3031 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3032 fdp, req); 3033 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3034 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3035 continue; 3036 bzero(kif, sizeof(*kif)); 3037 kif->kf_structsize = sizeof(*kif); 3038 ks = NULL; 3039 vp = NULL; 3040 so = NULL; 3041 tp = NULL; 3042 shmfd = NULL; 3043 kif->kf_fd = i; 3044 3045 switch (fp->f_type) { 3046 case DTYPE_VNODE: 3047 kif->kf_type = KF_TYPE_VNODE; 3048 vp = fp->f_vnode; 3049 break; 3050 3051 case DTYPE_SOCKET: 3052 kif->kf_type = KF_TYPE_SOCKET; 3053 so = fp->f_data; 3054 break; 3055 3056 case DTYPE_PIPE: 3057 kif->kf_type = KF_TYPE_PIPE; 3058 break; 3059 3060 case DTYPE_FIFO: 3061 kif->kf_type = KF_TYPE_FIFO; 3062 vp = fp->f_vnode; 3063 break; 3064 3065 case DTYPE_KQUEUE: 3066 kif->kf_type = KF_TYPE_KQUEUE; 3067 break; 3068 3069 case DTYPE_CRYPTO: 3070 kif->kf_type = KF_TYPE_CRYPTO; 3071 break; 3072 3073 case DTYPE_MQUEUE: 3074 kif->kf_type = KF_TYPE_MQUEUE; 3075 break; 3076 3077 case DTYPE_SHM: 3078 kif->kf_type = KF_TYPE_SHM; 3079 shmfd = fp->f_data; 3080 break; 3081 3082 case DTYPE_SEM: 3083 kif->kf_type = KF_TYPE_SEM; 3084 ks = fp->f_data; 3085 break; 3086 3087 case DTYPE_PTS: 3088 kif->kf_type = KF_TYPE_PTS; 3089 tp = fp->f_data; 3090 break; 3091 3092 case DTYPE_PROCDESC: 3093 kif->kf_type = KF_TYPE_PROCDESC; 3094 break; 3095 3096 default: 3097 kif->kf_type = KF_TYPE_UNKNOWN; 3098 break; 3099 } 3100 kif->kf_ref_count = fp->f_count; 3101 if (fp->f_flag & FREAD) 3102 kif->kf_flags |= KF_FLAG_READ; 3103 if (fp->f_flag & FWRITE) 3104 kif->kf_flags |= KF_FLAG_WRITE; 3105 if (fp->f_flag & FAPPEND) 3106 kif->kf_flags |= KF_FLAG_APPEND; 3107 if (fp->f_flag & FASYNC) 3108 kif->kf_flags |= KF_FLAG_ASYNC; 3109 if (fp->f_flag & FFSYNC) 3110 kif->kf_flags |= KF_FLAG_FSYNC; 3111 if (fp->f_flag & FNONBLOCK) 3112 kif->kf_flags |= KF_FLAG_NONBLOCK; 3113 if (fp->f_flag & O_DIRECT) 3114 kif->kf_flags |= KF_FLAG_DIRECT; 3115 if (fp->f_flag & FHASLOCK) 3116 kif->kf_flags |= KF_FLAG_HASLOCK; 3117 kif->kf_offset = foffset_get(fp); 3118 if (vp != NULL) { 3119 vref(vp); 3120 switch (vp->v_type) { 3121 case VNON: 3122 kif->kf_vnode_type = KF_VTYPE_VNON; 3123 break; 3124 case VREG: 3125 kif->kf_vnode_type = KF_VTYPE_VREG; 3126 break; 3127 case VDIR: 3128 kif->kf_vnode_type = KF_VTYPE_VDIR; 3129 break; 3130 case VBLK: 3131 kif->kf_vnode_type = KF_VTYPE_VBLK; 3132 break; 3133 case VCHR: 3134 kif->kf_vnode_type = KF_VTYPE_VCHR; 3135 break; 3136 case VLNK: 3137 kif->kf_vnode_type = KF_VTYPE_VLNK; 3138 break; 3139 case VSOCK: 3140 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3141 break; 3142 case VFIFO: 3143 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3144 break; 3145 case VBAD: 3146 kif->kf_vnode_type = KF_VTYPE_VBAD; 3147 break; 3148 default: 3149 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3150 break; 3151 } 3152 /* 3153 * It is OK to drop the filedesc lock here as we will 3154 * re-validate and re-evaluate its properties when 3155 * the loop continues. 3156 */ 3157 freepath = NULL; 3158 fullpath = "-"; 3159 FILEDESC_SUNLOCK(fdp); 3160 vn_fullpath(curthread, vp, &fullpath, &freepath); 3161 vrele(vp); 3162 strlcpy(kif->kf_path, fullpath, 3163 sizeof(kif->kf_path)); 3164 if (freepath != NULL) 3165 free(freepath, M_TEMP); 3166 FILEDESC_SLOCK(fdp); 3167 } 3168 if (so != NULL) { 3169 struct sockaddr *sa; 3170 3171 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3172 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3173 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3174 free(sa, M_SONAME); 3175 } 3176 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3177 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3178 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3179 free(sa, M_SONAME); 3180 } 3181 kif->kf_sock_domain = 3182 so->so_proto->pr_domain->dom_family; 3183 kif->kf_sock_type = so->so_type; 3184 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3185 } 3186 if (tp != NULL) { 3187 strlcpy(kif->kf_path, tty_devname(tp), 3188 sizeof(kif->kf_path)); 3189 } 3190 if (shmfd != NULL) 3191 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3192 if (ks != NULL && ksem_info != NULL) 3193 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL); 3194 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3195 if (error) 3196 break; 3197 } 3198 FILEDESC_SUNLOCK(fdp); 3199 fddrop(fdp); 3200 free(kif, M_TEMP); 3201 return (0); 3202 } 3203 3204 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 3205 CTLFLAG_RD||CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 3206 "Process ofiledesc entries"); 3207 #endif /* COMPAT_FREEBSD7 */ 3208 3209 #ifdef KINFO_FILE_SIZE 3210 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3211 #endif 3212 3213 struct export_fd_buf { 3214 struct filedesc *fdp; 3215 struct sbuf *sb; 3216 ssize_t remainder; 3217 struct kinfo_file kif; 3218 }; 3219 3220 static int 3221 export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt, 3222 int64_t offset, cap_rights_t *rightsp, struct export_fd_buf *efbuf) 3223 { 3224 struct { 3225 int fflag; 3226 int kf_fflag; 3227 } fflags_table[] = { 3228 { FAPPEND, KF_FLAG_APPEND }, 3229 { FASYNC, KF_FLAG_ASYNC }, 3230 { FFSYNC, KF_FLAG_FSYNC }, 3231 { FHASLOCK, KF_FLAG_HASLOCK }, 3232 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3233 { FREAD, KF_FLAG_READ }, 3234 { FWRITE, KF_FLAG_WRITE }, 3235 { O_CREAT, KF_FLAG_CREAT }, 3236 { O_DIRECT, KF_FLAG_DIRECT }, 3237 { O_EXCL, KF_FLAG_EXCL }, 3238 { O_EXEC, KF_FLAG_EXEC }, 3239 { O_EXLOCK, KF_FLAG_EXLOCK }, 3240 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3241 { O_SHLOCK, KF_FLAG_SHLOCK }, 3242 { O_TRUNC, KF_FLAG_TRUNC } 3243 }; 3244 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3245 struct kinfo_file *kif; 3246 struct vnode *vp; 3247 int error, locked; 3248 unsigned int i; 3249 3250 if (efbuf->remainder == 0) 3251 return (0); 3252 kif = &efbuf->kif; 3253 bzero(kif, sizeof(*kif)); 3254 locked = efbuf->fdp != NULL; 3255 switch (type) { 3256 case KF_TYPE_FIFO: 3257 case KF_TYPE_VNODE: 3258 if (locked) { 3259 FILEDESC_SUNLOCK(efbuf->fdp); 3260 locked = 0; 3261 } 3262 vp = (struct vnode *)data; 3263 error = fill_vnode_info(vp, kif); 3264 vrele(vp); 3265 break; 3266 case KF_TYPE_SOCKET: 3267 error = fill_socket_info((struct socket *)data, kif); 3268 break; 3269 case KF_TYPE_PIPE: 3270 error = fill_pipe_info((struct pipe *)data, kif); 3271 break; 3272 case KF_TYPE_PTS: 3273 error = fill_pts_info((struct tty *)data, kif); 3274 break; 3275 case KF_TYPE_PROCDESC: 3276 error = fill_procdesc_info((struct procdesc *)data, kif); 3277 break; 3278 case KF_TYPE_SEM: 3279 error = fill_sem_info((struct file *)data, kif); 3280 break; 3281 case KF_TYPE_SHM: 3282 error = fill_shm_info((struct file *)data, kif); 3283 break; 3284 default: 3285 error = 0; 3286 } 3287 if (error == 0) 3288 kif->kf_status |= KF_ATTR_VALID; 3289 3290 /* 3291 * Translate file access flags. 3292 */ 3293 for (i = 0; i < NFFLAGS; i++) 3294 if (fflags & fflags_table[i].fflag) 3295 kif->kf_flags |= fflags_table[i].kf_fflag; 3296 if (rightsp != NULL) 3297 kif->kf_cap_rights = *rightsp; 3298 else 3299 cap_rights_init(&kif->kf_cap_rights); 3300 kif->kf_fd = fd; 3301 kif->kf_type = type; 3302 kif->kf_ref_count = refcnt; 3303 kif->kf_offset = offset; 3304 /* Pack record size down */ 3305 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3306 strlen(kif->kf_path) + 1; 3307 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3308 if (efbuf->remainder != -1) { 3309 if (efbuf->remainder < kif->kf_structsize) { 3310 /* Terminate export. */ 3311 efbuf->remainder = 0; 3312 if (efbuf->fdp != NULL && !locked) 3313 FILEDESC_SLOCK(efbuf->fdp); 3314 return (0); 3315 } 3316 efbuf->remainder -= kif->kf_structsize; 3317 } 3318 if (locked) 3319 FILEDESC_SUNLOCK(efbuf->fdp); 3320 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize); 3321 if (efbuf->fdp != NULL) 3322 FILEDESC_SLOCK(efbuf->fdp); 3323 return (error); 3324 } 3325 3326 /* 3327 * Store a process file descriptor information to sbuf. 3328 * 3329 * Takes a locked proc as argument, and returns with the proc unlocked. 3330 */ 3331 int 3332 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3333 { 3334 struct file *fp; 3335 struct filedesc *fdp; 3336 struct export_fd_buf *efbuf; 3337 struct vnode *cttyvp, *textvp, *tracevp; 3338 int64_t offset; 3339 void *data; 3340 int error, i; 3341 int type, refcnt, fflags; 3342 cap_rights_t rights; 3343 3344 PROC_LOCK_ASSERT(p, MA_OWNED); 3345 3346 /* ktrace vnode */ 3347 tracevp = p->p_tracevp; 3348 if (tracevp != NULL) 3349 vref(tracevp); 3350 /* text vnode */ 3351 textvp = p->p_textvp; 3352 if (textvp != NULL) 3353 vref(textvp); 3354 /* Controlling tty. */ 3355 cttyvp = NULL; 3356 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3357 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3358 if (cttyvp != NULL) 3359 vref(cttyvp); 3360 } 3361 fdp = fdhold(p); 3362 PROC_UNLOCK(p); 3363 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3364 efbuf->fdp = NULL; 3365 efbuf->sb = sb; 3366 efbuf->remainder = maxlen; 3367 if (tracevp != NULL) 3368 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3369 FREAD | FWRITE, -1, -1, NULL, efbuf); 3370 if (textvp != NULL) 3371 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3372 FREAD, -1, -1, NULL, efbuf); 3373 if (cttyvp != NULL) 3374 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3375 FREAD | FWRITE, -1, -1, NULL, efbuf); 3376 error = 0; 3377 if (fdp == NULL) 3378 goto fail; 3379 efbuf->fdp = fdp; 3380 FILEDESC_SLOCK(fdp); 3381 /* working directory */ 3382 if (fdp->fd_cdir != NULL) { 3383 vref(fdp->fd_cdir); 3384 data = fdp->fd_cdir; 3385 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3386 FREAD, -1, -1, NULL, efbuf); 3387 } 3388 /* root directory */ 3389 if (fdp->fd_rdir != NULL) { 3390 vref(fdp->fd_rdir); 3391 data = fdp->fd_rdir; 3392 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3393 FREAD, -1, -1, NULL, efbuf); 3394 } 3395 /* jail directory */ 3396 if (fdp->fd_jdir != NULL) { 3397 vref(fdp->fd_jdir); 3398 data = fdp->fd_jdir; 3399 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3400 FREAD, -1, -1, NULL, efbuf); 3401 } 3402 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3403 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3404 continue; 3405 data = NULL; 3406 #ifdef CAPABILITIES 3407 rights = *cap_rights(fdp, i); 3408 #else /* !CAPABILITIES */ 3409 cap_rights_init(&rights); 3410 #endif 3411 switch (fp->f_type) { 3412 case DTYPE_VNODE: 3413 type = KF_TYPE_VNODE; 3414 vref(fp->f_vnode); 3415 data = fp->f_vnode; 3416 break; 3417 3418 case DTYPE_SOCKET: 3419 type = KF_TYPE_SOCKET; 3420 data = fp->f_data; 3421 break; 3422 3423 case DTYPE_PIPE: 3424 type = KF_TYPE_PIPE; 3425 data = fp->f_data; 3426 break; 3427 3428 case DTYPE_FIFO: 3429 type = KF_TYPE_FIFO; 3430 vref(fp->f_vnode); 3431 data = fp->f_vnode; 3432 break; 3433 3434 case DTYPE_KQUEUE: 3435 type = KF_TYPE_KQUEUE; 3436 break; 3437 3438 case DTYPE_CRYPTO: 3439 type = KF_TYPE_CRYPTO; 3440 break; 3441 3442 case DTYPE_MQUEUE: 3443 type = KF_TYPE_MQUEUE; 3444 break; 3445 3446 case DTYPE_SHM: 3447 type = KF_TYPE_SHM; 3448 data = fp; 3449 break; 3450 3451 case DTYPE_SEM: 3452 type = KF_TYPE_SEM; 3453 data = fp; 3454 break; 3455 3456 case DTYPE_PTS: 3457 type = KF_TYPE_PTS; 3458 data = fp->f_data; 3459 break; 3460 3461 case DTYPE_PROCDESC: 3462 type = KF_TYPE_PROCDESC; 3463 data = fp->f_data; 3464 break; 3465 3466 default: 3467 type = KF_TYPE_UNKNOWN; 3468 break; 3469 } 3470 refcnt = fp->f_count; 3471 fflags = fp->f_flag; 3472 offset = foffset_get(fp); 3473 3474 /* 3475 * Create sysctl entry. 3476 * It is OK to drop the filedesc lock here as we will 3477 * re-validate and re-evaluate its properties when 3478 * the loop continues. 3479 */ 3480 error = export_fd_to_sb(data, type, i, fflags, refcnt, 3481 offset, &rights, efbuf); 3482 if (error != 0) 3483 break; 3484 } 3485 FILEDESC_SUNLOCK(fdp); 3486 fddrop(fdp); 3487 fail: 3488 free(efbuf, M_TEMP); 3489 return (error); 3490 } 3491 3492 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3493 3494 /* 3495 * Get per-process file descriptors for use by procstat(1), et al. 3496 */ 3497 static int 3498 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3499 { 3500 struct sbuf sb; 3501 struct proc *p; 3502 ssize_t maxlen; 3503 int error, error2, *name; 3504 3505 name = (int *)arg1; 3506 3507 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3508 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3509 if (error != 0) { 3510 sbuf_delete(&sb); 3511 return (error); 3512 } 3513 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3514 error = kern_proc_filedesc_out(p, &sb, maxlen); 3515 error2 = sbuf_finish(&sb); 3516 sbuf_delete(&sb); 3517 return (error != 0 ? error : error2); 3518 } 3519 3520 int 3521 vntype_to_kinfo(int vtype) 3522 { 3523 struct { 3524 int vtype; 3525 int kf_vtype; 3526 } vtypes_table[] = { 3527 { VBAD, KF_VTYPE_VBAD }, 3528 { VBLK, KF_VTYPE_VBLK }, 3529 { VCHR, KF_VTYPE_VCHR }, 3530 { VDIR, KF_VTYPE_VDIR }, 3531 { VFIFO, KF_VTYPE_VFIFO }, 3532 { VLNK, KF_VTYPE_VLNK }, 3533 { VNON, KF_VTYPE_VNON }, 3534 { VREG, KF_VTYPE_VREG }, 3535 { VSOCK, KF_VTYPE_VSOCK } 3536 }; 3537 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3538 unsigned int i; 3539 3540 /* 3541 * Perform vtype translation. 3542 */ 3543 for (i = 0; i < NVTYPES; i++) 3544 if (vtypes_table[i].vtype == vtype) 3545 break; 3546 if (i < NVTYPES) 3547 return (vtypes_table[i].kf_vtype); 3548 3549 return (KF_VTYPE_UNKNOWN); 3550 } 3551 3552 static int 3553 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3554 { 3555 struct vattr va; 3556 char *fullpath, *freepath; 3557 int error; 3558 3559 if (vp == NULL) 3560 return (1); 3561 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3562 freepath = NULL; 3563 fullpath = "-"; 3564 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3565 if (error == 0) { 3566 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3567 } 3568 if (freepath != NULL) 3569 free(freepath, M_TEMP); 3570 3571 /* 3572 * Retrieve vnode attributes. 3573 */ 3574 va.va_fsid = VNOVAL; 3575 va.va_rdev = NODEV; 3576 vn_lock(vp, LK_SHARED | LK_RETRY); 3577 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3578 VOP_UNLOCK(vp, 0); 3579 if (error != 0) 3580 return (error); 3581 if (va.va_fsid != VNOVAL) 3582 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3583 else 3584 kif->kf_un.kf_file.kf_file_fsid = 3585 vp->v_mount->mnt_stat.f_fsid.val[0]; 3586 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3587 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3588 kif->kf_un.kf_file.kf_file_size = va.va_size; 3589 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3590 return (0); 3591 } 3592 3593 static int 3594 fill_socket_info(struct socket *so, struct kinfo_file *kif) 3595 { 3596 struct sockaddr *sa; 3597 struct inpcb *inpcb; 3598 struct unpcb *unpcb; 3599 int error; 3600 3601 if (so == NULL) 3602 return (1); 3603 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3604 kif->kf_sock_type = so->so_type; 3605 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3606 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3607 switch(kif->kf_sock_domain) { 3608 case AF_INET: 3609 case AF_INET6: 3610 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3611 if (so->so_pcb != NULL) { 3612 inpcb = (struct inpcb *)(so->so_pcb); 3613 kif->kf_un.kf_sock.kf_sock_inpcb = 3614 (uintptr_t)inpcb->inp_ppcb; 3615 } 3616 } 3617 break; 3618 case AF_UNIX: 3619 if (so->so_pcb != NULL) { 3620 unpcb = (struct unpcb *)(so->so_pcb); 3621 if (unpcb->unp_conn) { 3622 kif->kf_un.kf_sock.kf_sock_unpconn = 3623 (uintptr_t)unpcb->unp_conn; 3624 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3625 so->so_rcv.sb_state; 3626 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3627 so->so_snd.sb_state; 3628 } 3629 } 3630 break; 3631 } 3632 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3633 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3634 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3635 free(sa, M_SONAME); 3636 } 3637 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3638 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3639 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3640 free(sa, M_SONAME); 3641 } 3642 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3643 sizeof(kif->kf_path)); 3644 return (0); 3645 } 3646 3647 static int 3648 fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3649 { 3650 3651 if (tp == NULL) 3652 return (1); 3653 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3654 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3655 return (0); 3656 } 3657 3658 static int 3659 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3660 { 3661 3662 if (pi == NULL) 3663 return (1); 3664 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3665 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3666 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3667 return (0); 3668 } 3669 3670 static int 3671 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3672 { 3673 3674 if (pdp == NULL) 3675 return (1); 3676 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3677 return (0); 3678 } 3679 3680 static int 3681 fill_sem_info(struct file *fp, struct kinfo_file *kif) 3682 { 3683 struct thread *td; 3684 struct stat sb; 3685 3686 td = curthread; 3687 if (fp->f_data == NULL) 3688 return (1); 3689 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3690 return (1); 3691 if (ksem_info == NULL) 3692 return (1); 3693 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path), 3694 &kif->kf_un.kf_sem.kf_sem_value); 3695 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode; 3696 return (0); 3697 } 3698 3699 static int 3700 fill_shm_info(struct file *fp, struct kinfo_file *kif) 3701 { 3702 struct thread *td; 3703 struct stat sb; 3704 3705 td = curthread; 3706 if (fp->f_data == NULL) 3707 return (1); 3708 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3709 return (1); 3710 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3711 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3712 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3713 return (0); 3714 } 3715 3716 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 3717 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 3718 "Process filedesc entries"); 3719 3720 #ifdef DDB 3721 /* 3722 * For the purposes of debugging, generate a human-readable string for the 3723 * file type. 3724 */ 3725 static const char * 3726 file_type_to_name(short type) 3727 { 3728 3729 switch (type) { 3730 case 0: 3731 return ("zero"); 3732 case DTYPE_VNODE: 3733 return ("vnod"); 3734 case DTYPE_SOCKET: 3735 return ("sock"); 3736 case DTYPE_PIPE: 3737 return ("pipe"); 3738 case DTYPE_FIFO: 3739 return ("fifo"); 3740 case DTYPE_KQUEUE: 3741 return ("kque"); 3742 case DTYPE_CRYPTO: 3743 return ("crpt"); 3744 case DTYPE_MQUEUE: 3745 return ("mque"); 3746 case DTYPE_SHM: 3747 return ("shm"); 3748 case DTYPE_SEM: 3749 return ("ksem"); 3750 default: 3751 return ("unkn"); 3752 } 3753 } 3754 3755 /* 3756 * For the purposes of debugging, identify a process (if any, perhaps one of 3757 * many) that references the passed file in its file descriptor array. Return 3758 * NULL if none. 3759 */ 3760 static struct proc * 3761 file_to_first_proc(struct file *fp) 3762 { 3763 struct filedesc *fdp; 3764 struct proc *p; 3765 int n; 3766 3767 FOREACH_PROC_IN_SYSTEM(p) { 3768 if (p->p_state == PRS_NEW) 3769 continue; 3770 fdp = p->p_fd; 3771 if (fdp == NULL) 3772 continue; 3773 for (n = 0; n <= fdp->fd_lastfile; n++) { 3774 if (fp == fdp->fd_ofiles[n].fde_file) 3775 return (p); 3776 } 3777 } 3778 return (NULL); 3779 } 3780 3781 static void 3782 db_print_file(struct file *fp, int header) 3783 { 3784 struct proc *p; 3785 3786 if (header) 3787 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3788 "File", "Type", "Data", "Flag", "GCFl", "Count", 3789 "MCount", "Vnode", "FPID", "FCmd"); 3790 p = file_to_first_proc(fp); 3791 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3792 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3793 0, fp->f_count, 0, fp->f_vnode, 3794 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3795 } 3796 3797 DB_SHOW_COMMAND(file, db_show_file) 3798 { 3799 struct file *fp; 3800 3801 if (!have_addr) { 3802 db_printf("usage: show file <addr>\n"); 3803 return; 3804 } 3805 fp = (struct file *)addr; 3806 db_print_file(fp, 1); 3807 } 3808 3809 DB_SHOW_COMMAND(files, db_show_files) 3810 { 3811 struct filedesc *fdp; 3812 struct file *fp; 3813 struct proc *p; 3814 int header; 3815 int n; 3816 3817 header = 1; 3818 FOREACH_PROC_IN_SYSTEM(p) { 3819 if (p->p_state == PRS_NEW) 3820 continue; 3821 if ((fdp = p->p_fd) == NULL) 3822 continue; 3823 for (n = 0; n <= fdp->fd_lastfile; ++n) { 3824 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3825 continue; 3826 db_print_file(fp, header); 3827 header = 0; 3828 } 3829 } 3830 } 3831 #endif 3832 3833 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3834 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3835 3836 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3837 &maxfiles, 0, "Maximum number of files"); 3838 3839 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3840 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3841 3842 /* ARGSUSED*/ 3843 static void 3844 filelistinit(void *dummy) 3845 { 3846 3847 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3848 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3849 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3850 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3851 } 3852 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3853 3854 /*-------------------------------------------------------------------*/ 3855 3856 static int 3857 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3858 int flags, struct thread *td) 3859 { 3860 3861 return (EBADF); 3862 } 3863 3864 static int 3865 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3866 struct thread *td) 3867 { 3868 3869 return (EINVAL); 3870 } 3871 3872 static int 3873 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3874 struct thread *td) 3875 { 3876 3877 return (EBADF); 3878 } 3879 3880 static int 3881 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3882 struct thread *td) 3883 { 3884 3885 return (0); 3886 } 3887 3888 static int 3889 badfo_kqfilter(struct file *fp, struct knote *kn) 3890 { 3891 3892 return (EBADF); 3893 } 3894 3895 static int 3896 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3897 struct thread *td) 3898 { 3899 3900 return (EBADF); 3901 } 3902 3903 static int 3904 badfo_close(struct file *fp, struct thread *td) 3905 { 3906 3907 return (EBADF); 3908 } 3909 3910 static int 3911 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3912 struct thread *td) 3913 { 3914 3915 return (EBADF); 3916 } 3917 3918 static int 3919 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3920 struct thread *td) 3921 { 3922 3923 return (EBADF); 3924 } 3925 3926 static int 3927 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3928 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3929 int kflags, struct sendfile_sync *sfs, struct thread *td) 3930 { 3931 3932 return (EBADF); 3933 } 3934 3935 struct fileops badfileops = { 3936 .fo_read = badfo_readwrite, 3937 .fo_write = badfo_readwrite, 3938 .fo_truncate = badfo_truncate, 3939 .fo_ioctl = badfo_ioctl, 3940 .fo_poll = badfo_poll, 3941 .fo_kqfilter = badfo_kqfilter, 3942 .fo_stat = badfo_stat, 3943 .fo_close = badfo_close, 3944 .fo_chmod = badfo_chmod, 3945 .fo_chown = badfo_chown, 3946 .fo_sendfile = badfo_sendfile, 3947 }; 3948 3949 int 3950 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3951 struct thread *td) 3952 { 3953 3954 return (EINVAL); 3955 } 3956 3957 int 3958 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3959 struct thread *td) 3960 { 3961 3962 return (EINVAL); 3963 } 3964 3965 int 3966 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3967 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3968 int kflags, struct sendfile_sync *sfs, struct thread *td) 3969 { 3970 3971 return (EINVAL); 3972 } 3973 3974 /*-------------------------------------------------------------------*/ 3975 3976 /* 3977 * File Descriptor pseudo-device driver (/dev/fd/). 3978 * 3979 * Opening minor device N dup()s the file (if any) connected to file 3980 * descriptor N belonging to the calling process. Note that this driver 3981 * consists of only the ``open()'' routine, because all subsequent 3982 * references to this file will be direct to the other driver. 3983 * 3984 * XXX: we could give this one a cloning event handler if necessary. 3985 */ 3986 3987 /* ARGSUSED */ 3988 static int 3989 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 3990 { 3991 3992 /* 3993 * XXX Kludge: set curthread->td_dupfd to contain the value of the 3994 * the file descriptor being sought for duplication. The error 3995 * return ensures that the vnode for this device will be released 3996 * by vn_open. Open will detect this special error and take the 3997 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 3998 * will simply report the error. 3999 */ 4000 td->td_dupfd = dev2unit(dev); 4001 return (ENODEV); 4002 } 4003 4004 static struct cdevsw fildesc_cdevsw = { 4005 .d_version = D_VERSION, 4006 .d_open = fdopen, 4007 .d_name = "FD", 4008 }; 4009 4010 static void 4011 fildesc_drvinit(void *unused) 4012 { 4013 struct cdev *dev; 4014 4015 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4016 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4017 make_dev_alias(dev, "stdin"); 4018 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4019 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4020 make_dev_alias(dev, "stdout"); 4021 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4022 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4023 make_dev_alias(dev, "stderr"); 4024 } 4025 4026 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4027