1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_capsicum.h" 41 #include "opt_compat.h" 42 #include "opt_ddb.h" 43 #include "opt_ktrace.h" 44 #include "opt_procdesc.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 49 #include <sys/capability.h> 50 #include <sys/conf.h> 51 #include <sys/domain.h> 52 #include <sys/fcntl.h> 53 #include <sys/file.h> 54 #include <sys/filedesc.h> 55 #include <sys/filio.h> 56 #include <sys/jail.h> 57 #include <sys/kernel.h> 58 #include <sys/ksem.h> 59 #include <sys/limits.h> 60 #include <sys/lock.h> 61 #include <sys/malloc.h> 62 #include <sys/mman.h> 63 #include <sys/mount.h> 64 #include <sys/mqueue.h> 65 #include <sys/mutex.h> 66 #include <sys/namei.h> 67 #include <sys/selinfo.h> 68 #include <sys/pipe.h> 69 #include <sys/priv.h> 70 #include <sys/proc.h> 71 #include <sys/procdesc.h> 72 #include <sys/protosw.h> 73 #include <sys/racct.h> 74 #include <sys/resourcevar.h> 75 #include <sys/sbuf.h> 76 #include <sys/signalvar.h> 77 #include <sys/socketvar.h> 78 #include <sys/stat.h> 79 #include <sys/sx.h> 80 #include <sys/syscallsubr.h> 81 #include <sys/sysctl.h> 82 #include <sys/sysproto.h> 83 #include <sys/tty.h> 84 #include <sys/unistd.h> 85 #include <sys/un.h> 86 #include <sys/unpcb.h> 87 #include <sys/user.h> 88 #include <sys/vnode.h> 89 #ifdef KTRACE 90 #include <sys/ktrace.h> 91 #endif 92 93 #include <net/vnet.h> 94 95 #include <netinet/in.h> 96 #include <netinet/in_pcb.h> 97 98 #include <security/audit/audit.h> 99 100 #include <vm/uma.h> 101 #include <vm/vm.h> 102 103 #include <ddb/ddb.h> 104 105 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 106 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 107 "file desc to leader structures"); 108 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 109 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 110 111 MALLOC_DECLARE(M_FADVISE); 112 113 static uma_zone_t file_zone; 114 115 void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value); 116 117 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 118 struct thread *td, int holdleaders); 119 static int fd_first_free(struct filedesc *fdp, int low, int size); 120 static int fd_last_used(struct filedesc *fdp, int size); 121 static void fdgrowtable(struct filedesc *fdp, int nfd); 122 static void 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); 132 133 /* 134 * Each process has: 135 * 136 * - An array of open file descriptors (fd_ofiles) 137 * - An array of file flags (fd_ofileflags) 138 * - A bitmap recording which descriptors are in use (fd_map) 139 * 140 * A process starts out with NDFILE descriptors. The value of NDFILE has 141 * been selected based the historical limit of 20 open files, and an 142 * assumption that the majority of processes, especially short-lived 143 * processes like shells, will never need more. 144 * 145 * If this initial allocation is exhausted, a larger descriptor table and 146 * map are allocated dynamically, and the pointers in the process's struct 147 * filedesc are updated to point to those. This is repeated every time 148 * the process runs out of file descriptors (provided it hasn't hit its 149 * resource limit). 150 * 151 * Since threads may hold references to individual descriptor table 152 * entries, the tables are never freed. Instead, they are placed on a 153 * linked list and freed only when the struct filedesc is released. 154 */ 155 #define NDFILE 20 156 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 157 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 158 #define NDSLOT(x) ((x) / NDENTRIES) 159 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 160 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 161 162 /* 163 * SLIST entry used to keep track of ofiles which must be reclaimed when 164 * the process exits. 165 */ 166 struct freetable { 167 struct filedescent *ft_table; 168 SLIST_ENTRY(freetable) ft_next; 169 }; 170 171 /* 172 * Initial allocation: a filedesc structure + the head of SLIST used to 173 * keep track of old ofiles + enough space for NDFILE descriptors. 174 */ 175 struct filedesc0 { 176 struct filedesc fd_fd; 177 SLIST_HEAD(, freetable) fd_free; 178 struct filedescent fd_dfiles[NDFILE]; 179 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 180 }; 181 182 /* 183 * Descriptor management. 184 */ 185 volatile int openfiles; /* actual number of open files */ 186 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 187 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 188 189 /* A mutex to protect the association between a proc and filedesc. */ 190 static struct mtx fdesc_mtx; 191 192 /* 193 * If low >= size, just return low. Otherwise find the first zero bit in the 194 * given bitmap, starting at low and not exceeding size - 1. Return size if 195 * not found. 196 */ 197 static int 198 fd_first_free(struct filedesc *fdp, int low, int size) 199 { 200 NDSLOTTYPE *map = fdp->fd_map; 201 NDSLOTTYPE mask; 202 int off, maxoff; 203 204 if (low >= size) 205 return (low); 206 207 off = NDSLOT(low); 208 if (low % NDENTRIES) { 209 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 210 if ((mask &= ~map[off]) != 0UL) 211 return (off * NDENTRIES + ffsl(mask) - 1); 212 ++off; 213 } 214 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 215 if (map[off] != ~0UL) 216 return (off * NDENTRIES + ffsl(~map[off]) - 1); 217 return (size); 218 } 219 220 /* 221 * Find the highest non-zero bit in the given bitmap, starting at 0 and 222 * not exceeding size - 1. Return -1 if not found. 223 */ 224 static int 225 fd_last_used(struct filedesc *fdp, int size) 226 { 227 NDSLOTTYPE *map = fdp->fd_map; 228 NDSLOTTYPE mask; 229 int off, minoff; 230 231 off = NDSLOT(size); 232 if (size % NDENTRIES) { 233 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 234 if ((mask &= map[off]) != 0) 235 return (off * NDENTRIES + flsl(mask) - 1); 236 --off; 237 } 238 for (minoff = NDSLOT(0); off >= minoff; --off) 239 if (map[off] != 0) 240 return (off * NDENTRIES + flsl(map[off]) - 1); 241 return (-1); 242 } 243 244 static int 245 fdisused(struct filedesc *fdp, int fd) 246 { 247 248 FILEDESC_LOCK_ASSERT(fdp); 249 250 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 251 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 252 253 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 254 } 255 256 /* 257 * Mark a file descriptor as used. 258 */ 259 static void 260 fdused(struct filedesc *fdp, int fd) 261 { 262 263 FILEDESC_XLOCK_ASSERT(fdp); 264 265 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 266 267 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 268 if (fd > fdp->fd_lastfile) 269 fdp->fd_lastfile = fd; 270 if (fd == fdp->fd_freefile) 271 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 272 } 273 274 /* 275 * Mark a file descriptor as unused. 276 */ 277 static void 278 fdunused(struct filedesc *fdp, int fd) 279 { 280 281 FILEDESC_XLOCK_ASSERT(fdp); 282 283 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 284 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 285 ("fd=%d is still in use", fd)); 286 287 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 288 if (fd < fdp->fd_freefile) 289 fdp->fd_freefile = fd; 290 if (fd == fdp->fd_lastfile) 291 fdp->fd_lastfile = fd_last_used(fdp, fd); 292 } 293 294 /* 295 * Free a file descriptor. 296 */ 297 static inline void 298 fdfree(struct filedesc *fdp, int fd) 299 { 300 struct filedescent *fde; 301 302 fde = &fdp->fd_ofiles[fd]; 303 filecaps_free(&fde->fde_caps); 304 bzero(fde, sizeof(*fde)); 305 fdunused(fdp, fd); 306 } 307 308 /* 309 * System calls on descriptors. 310 */ 311 #ifndef _SYS_SYSPROTO_H_ 312 struct getdtablesize_args { 313 int dummy; 314 }; 315 #endif 316 /* ARGSUSED */ 317 int 318 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 319 { 320 struct proc *p = td->td_proc; 321 uint64_t lim; 322 323 PROC_LOCK(p); 324 td->td_retval[0] = 325 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 326 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 327 PROC_UNLOCK(p); 328 if (lim < td->td_retval[0]) 329 td->td_retval[0] = lim; 330 return (0); 331 } 332 333 /* 334 * Duplicate a file descriptor to a particular value. 335 * 336 * Note: keep in mind that a potential race condition exists when closing 337 * descriptors from a shared descriptor table (via rfork). 338 */ 339 #ifndef _SYS_SYSPROTO_H_ 340 struct dup2_args { 341 u_int from; 342 u_int to; 343 }; 344 #endif 345 /* ARGSUSED */ 346 int 347 sys_dup2(struct thread *td, struct dup2_args *uap) 348 { 349 350 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 351 td->td_retval)); 352 } 353 354 /* 355 * Duplicate a file descriptor. 356 */ 357 #ifndef _SYS_SYSPROTO_H_ 358 struct dup_args { 359 u_int fd; 360 }; 361 #endif 362 /* ARGSUSED */ 363 int 364 sys_dup(struct thread *td, struct dup_args *uap) 365 { 366 367 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 368 } 369 370 /* 371 * The file control system call. 372 */ 373 #ifndef _SYS_SYSPROTO_H_ 374 struct fcntl_args { 375 int fd; 376 int cmd; 377 long arg; 378 }; 379 #endif 380 /* ARGSUSED */ 381 int 382 sys_fcntl(struct thread *td, struct fcntl_args *uap) 383 { 384 struct flock fl; 385 struct __oflock ofl; 386 intptr_t arg; 387 int error; 388 int cmd; 389 390 error = 0; 391 cmd = uap->cmd; 392 switch (uap->cmd) { 393 case F_OGETLK: 394 case F_OSETLK: 395 case F_OSETLKW: 396 /* 397 * Convert old flock structure to new. 398 */ 399 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 400 fl.l_start = ofl.l_start; 401 fl.l_len = ofl.l_len; 402 fl.l_pid = ofl.l_pid; 403 fl.l_type = ofl.l_type; 404 fl.l_whence = ofl.l_whence; 405 fl.l_sysid = 0; 406 407 switch (uap->cmd) { 408 case F_OGETLK: 409 cmd = F_GETLK; 410 break; 411 case F_OSETLK: 412 cmd = F_SETLK; 413 break; 414 case F_OSETLKW: 415 cmd = F_SETLKW; 416 break; 417 } 418 arg = (intptr_t)&fl; 419 break; 420 case F_GETLK: 421 case F_SETLK: 422 case F_SETLKW: 423 case F_SETLK_REMOTE: 424 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 425 arg = (intptr_t)&fl; 426 break; 427 default: 428 arg = uap->arg; 429 break; 430 } 431 if (error) 432 return (error); 433 error = kern_fcntl(td, uap->fd, cmd, arg); 434 if (error) 435 return (error); 436 if (uap->cmd == F_OGETLK) { 437 ofl.l_start = fl.l_start; 438 ofl.l_len = fl.l_len; 439 ofl.l_pid = fl.l_pid; 440 ofl.l_type = fl.l_type; 441 ofl.l_whence = fl.l_whence; 442 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 443 } else if (uap->cmd == F_GETLK) { 444 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 445 } 446 return (error); 447 } 448 449 int 450 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 451 { 452 struct filedesc *fdp; 453 struct flock *flp; 454 struct file *fp, *fp2; 455 struct filedescent *fde; 456 struct proc *p; 457 struct vnode *vp; 458 int error, flg, tmp; 459 u_int old, new; 460 uint64_t bsize; 461 off_t foffset; 462 463 error = 0; 464 flg = F_POSIX; 465 p = td->td_proc; 466 fdp = p->p_fd; 467 468 switch (cmd) { 469 case F_DUPFD: 470 tmp = arg; 471 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 472 break; 473 474 case F_DUPFD_CLOEXEC: 475 tmp = arg; 476 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 477 td->td_retval); 478 break; 479 480 case F_DUP2FD: 481 tmp = arg; 482 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 483 break; 484 485 case F_DUP2FD_CLOEXEC: 486 tmp = arg; 487 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 488 td->td_retval); 489 break; 490 491 case F_GETFD: 492 FILEDESC_SLOCK(fdp); 493 if ((fp = fget_locked(fdp, fd)) == NULL) { 494 FILEDESC_SUNLOCK(fdp); 495 error = EBADF; 496 break; 497 } 498 fde = &fdp->fd_ofiles[fd]; 499 td->td_retval[0] = 500 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 501 FILEDESC_SUNLOCK(fdp); 502 break; 503 504 case F_SETFD: 505 FILEDESC_XLOCK(fdp); 506 if ((fp = fget_locked(fdp, fd)) == NULL) { 507 FILEDESC_XUNLOCK(fdp); 508 error = EBADF; 509 break; 510 } 511 fde = &fdp->fd_ofiles[fd]; 512 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 513 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 514 FILEDESC_XUNLOCK(fdp); 515 break; 516 517 case F_GETFL: 518 error = fget_unlocked(fdp, fd, CAP_FCNTL, F_GETFL, &fp, NULL); 519 if (error != 0) 520 break; 521 td->td_retval[0] = OFLAGS(fp->f_flag); 522 fdrop(fp, td); 523 break; 524 525 case F_SETFL: 526 error = fget_unlocked(fdp, fd, CAP_FCNTL, F_SETFL, &fp, NULL); 527 if (error != 0) 528 break; 529 do { 530 tmp = flg = fp->f_flag; 531 tmp &= ~FCNTLFLAGS; 532 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 533 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 534 tmp = fp->f_flag & FNONBLOCK; 535 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 536 if (error != 0) { 537 fdrop(fp, td); 538 break; 539 } 540 tmp = fp->f_flag & FASYNC; 541 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 542 if (error == 0) { 543 fdrop(fp, td); 544 break; 545 } 546 atomic_clear_int(&fp->f_flag, FNONBLOCK); 547 tmp = 0; 548 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 549 fdrop(fp, td); 550 break; 551 552 case F_GETOWN: 553 error = fget_unlocked(fdp, fd, CAP_FCNTL, F_GETOWN, &fp, NULL); 554 if (error != 0) 555 break; 556 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 557 if (error == 0) 558 td->td_retval[0] = tmp; 559 fdrop(fp, td); 560 break; 561 562 case F_SETOWN: 563 error = fget_unlocked(fdp, fd, CAP_FCNTL, F_SETOWN, &fp, NULL); 564 if (error != 0) 565 break; 566 tmp = arg; 567 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 568 fdrop(fp, td); 569 break; 570 571 case F_SETLK_REMOTE: 572 error = priv_check(td, PRIV_NFS_LOCKD); 573 if (error) 574 return (error); 575 flg = F_REMOTE; 576 goto do_setlk; 577 578 case F_SETLKW: 579 flg |= F_WAIT; 580 /* FALLTHROUGH F_SETLK */ 581 582 case F_SETLK: 583 do_setlk: 584 error = fget_unlocked(fdp, fd, CAP_FLOCK, 0, &fp, NULL); 585 if (error != 0) 586 break; 587 if (fp->f_type != DTYPE_VNODE) { 588 error = EBADF; 589 fdrop(fp, td); 590 break; 591 } 592 593 flp = (struct flock *)arg; 594 if (flp->l_whence == SEEK_CUR) { 595 foffset = foffset_get(fp); 596 if (foffset < 0 || 597 (flp->l_start > 0 && 598 foffset > OFF_MAX - flp->l_start)) { 599 FILEDESC_SUNLOCK(fdp); 600 error = EOVERFLOW; 601 fdrop(fp, td); 602 break; 603 } 604 flp->l_start += foffset; 605 } 606 607 vp = fp->f_vnode; 608 switch (flp->l_type) { 609 case F_RDLCK: 610 if ((fp->f_flag & FREAD) == 0) { 611 error = EBADF; 612 break; 613 } 614 PROC_LOCK(p->p_leader); 615 p->p_leader->p_flag |= P_ADVLOCK; 616 PROC_UNLOCK(p->p_leader); 617 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 618 flp, flg); 619 break; 620 case F_WRLCK: 621 if ((fp->f_flag & FWRITE) == 0) { 622 error = EBADF; 623 break; 624 } 625 PROC_LOCK(p->p_leader); 626 p->p_leader->p_flag |= P_ADVLOCK; 627 PROC_UNLOCK(p->p_leader); 628 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 629 flp, flg); 630 break; 631 case F_UNLCK: 632 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 633 flp, flg); 634 break; 635 case F_UNLCKSYS: 636 /* 637 * Temporary api for testing remote lock 638 * infrastructure. 639 */ 640 if (flg != F_REMOTE) { 641 error = EINVAL; 642 break; 643 } 644 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 645 F_UNLCKSYS, flp, flg); 646 break; 647 default: 648 error = EINVAL; 649 break; 650 } 651 if (error != 0 || flp->l_type == F_UNLCK || 652 flp->l_type == F_UNLCKSYS) { 653 fdrop(fp, td); 654 break; 655 } 656 657 /* 658 * Check for a race with close. 659 * 660 * The vnode is now advisory locked (or unlocked, but this case 661 * is not really important) as the caller requested. 662 * We had to drop the filedesc lock, so we need to recheck if 663 * the descriptor is still valid, because if it was closed 664 * in the meantime we need to remove advisory lock from the 665 * vnode - close on any descriptor leading to an advisory 666 * locked vnode, removes that lock. 667 * We will return 0 on purpose in that case, as the result of 668 * successful advisory lock might have been externally visible 669 * already. This is fine - effectively we pretend to the caller 670 * that the closing thread was a bit slower and that the 671 * advisory lock succeeded before the close. 672 */ 673 error = fget_unlocked(fdp, fd, 0, 0, &fp2, NULL); 674 if (error != 0) { 675 fdrop(fp, td); 676 break; 677 } 678 if (fp != fp2) { 679 flp->l_whence = SEEK_SET; 680 flp->l_start = 0; 681 flp->l_len = 0; 682 flp->l_type = F_UNLCK; 683 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 684 F_UNLCK, flp, F_POSIX); 685 } 686 fdrop(fp, td); 687 fdrop(fp2, td); 688 break; 689 690 case F_GETLK: 691 error = fget_unlocked(fdp, fd, CAP_FLOCK, 0, &fp, NULL); 692 if (error != 0) 693 break; 694 if (fp->f_type != DTYPE_VNODE) { 695 error = EBADF; 696 fdrop(fp, td); 697 break; 698 } 699 flp = (struct flock *)arg; 700 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 701 flp->l_type != F_UNLCK) { 702 error = EINVAL; 703 fdrop(fp, td); 704 break; 705 } 706 if (flp->l_whence == SEEK_CUR) { 707 foffset = foffset_get(fp); 708 if ((flp->l_start > 0 && 709 foffset > OFF_MAX - flp->l_start) || 710 (flp->l_start < 0 && 711 foffset < OFF_MIN - flp->l_start)) { 712 FILEDESC_SUNLOCK(fdp); 713 error = EOVERFLOW; 714 fdrop(fp, td); 715 break; 716 } 717 flp->l_start += foffset; 718 } 719 vp = fp->f_vnode; 720 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 721 F_POSIX); 722 fdrop(fp, td); 723 break; 724 725 case F_RDAHEAD: 726 arg = arg ? 128 * 1024: 0; 727 /* FALLTHROUGH */ 728 case F_READAHEAD: 729 error = fget_unlocked(fdp, fd, 0, 0, &fp, NULL); 730 if (error != 0) 731 break; 732 if (fp->f_type != DTYPE_VNODE) { 733 fdrop(fp, td); 734 error = EBADF; 735 break; 736 } 737 if (arg >= 0) { 738 vp = fp->f_vnode; 739 error = vn_lock(vp, LK_SHARED); 740 if (error != 0) { 741 fdrop(fp, td); 742 break; 743 } 744 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 745 VOP_UNLOCK(vp, 0); 746 fp->f_seqcount = (arg + bsize - 1) / bsize; 747 do { 748 new = old = fp->f_flag; 749 new |= FRDAHEAD; 750 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 751 } else { 752 do { 753 new = old = fp->f_flag; 754 new &= ~FRDAHEAD; 755 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 756 } 757 fdrop(fp, td); 758 break; 759 760 default: 761 error = EINVAL; 762 break; 763 } 764 return (error); 765 } 766 767 /* 768 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 769 */ 770 int 771 do_dup(struct thread *td, int flags, int old, int new, 772 register_t *retval) 773 { 774 struct filedesc *fdp; 775 struct filedescent *oldfde, *newfde; 776 struct proc *p; 777 struct file *fp; 778 struct file *delfp; 779 int error, maxfd; 780 781 p = td->td_proc; 782 fdp = p->p_fd; 783 784 /* 785 * Verify we have a valid descriptor to dup from and possibly to 786 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 787 * return EINVAL when the new descriptor is out of bounds. 788 */ 789 if (old < 0) 790 return (EBADF); 791 if (new < 0) 792 return (flags & DUP_FCNTL ? EINVAL : EBADF); 793 PROC_LOCK(p); 794 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 795 PROC_UNLOCK(p); 796 if (new >= maxfd) 797 return (flags & DUP_FCNTL ? EINVAL : EBADF); 798 799 FILEDESC_XLOCK(fdp); 800 if (fget_locked(fdp, old) == NULL) { 801 FILEDESC_XUNLOCK(fdp); 802 return (EBADF); 803 } 804 oldfde = &fdp->fd_ofiles[old]; 805 if (flags & DUP_FIXED && old == new) { 806 *retval = new; 807 if (flags & DUP_CLOEXEC) 808 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 809 FILEDESC_XUNLOCK(fdp); 810 return (0); 811 } 812 fp = oldfde->fde_file; 813 fhold(fp); 814 815 /* 816 * If the caller specified a file descriptor, make sure the file 817 * table is large enough to hold it, and grab it. Otherwise, just 818 * allocate a new descriptor the usual way. 819 */ 820 if (flags & DUP_FIXED) { 821 if (new >= fdp->fd_nfiles) { 822 /* 823 * The resource limits are here instead of e.g. 824 * fdalloc(), because the file descriptor table may be 825 * shared between processes, so we can't really use 826 * racct_add()/racct_sub(). Instead of counting the 827 * number of actually allocated descriptors, just put 828 * the limit on the size of the file descriptor table. 829 */ 830 #ifdef RACCT 831 PROC_LOCK(p); 832 error = racct_set(p, RACCT_NOFILE, new + 1); 833 PROC_UNLOCK(p); 834 if (error != 0) { 835 FILEDESC_XUNLOCK(fdp); 836 fdrop(fp, td); 837 return (EMFILE); 838 } 839 #endif 840 fdgrowtable(fdp, new + 1); 841 oldfde = &fdp->fd_ofiles[old]; 842 } 843 newfde = &fdp->fd_ofiles[new]; 844 if (newfde->fde_file == NULL) 845 fdused(fdp, new); 846 } else { 847 if ((error = fdalloc(td, new, &new)) != 0) { 848 FILEDESC_XUNLOCK(fdp); 849 fdrop(fp, td); 850 return (error); 851 } 852 newfde = &fdp->fd_ofiles[new]; 853 } 854 855 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 856 KASSERT(old != new, ("new fd is same as old")); 857 858 delfp = newfde->fde_file; 859 860 /* 861 * Duplicate the source descriptor. 862 */ 863 *newfde = *oldfde; 864 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 865 if ((flags & DUP_CLOEXEC) != 0) 866 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 867 else 868 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 869 if (new > fdp->fd_lastfile) 870 fdp->fd_lastfile = new; 871 *retval = new; 872 873 if (delfp != NULL) { 874 (void) closefp(fdp, new, delfp, td, 1); 875 /* closefp() drops the FILEDESC lock for us. */ 876 } else { 877 FILEDESC_XUNLOCK(fdp); 878 } 879 880 return (0); 881 } 882 883 /* 884 * If sigio is on the list associated with a process or process group, 885 * disable signalling from the device, remove sigio from the list and 886 * free sigio. 887 */ 888 void 889 funsetown(struct sigio **sigiop) 890 { 891 struct sigio *sigio; 892 893 SIGIO_LOCK(); 894 sigio = *sigiop; 895 if (sigio == NULL) { 896 SIGIO_UNLOCK(); 897 return; 898 } 899 *(sigio->sio_myref) = NULL; 900 if ((sigio)->sio_pgid < 0) { 901 struct pgrp *pg = (sigio)->sio_pgrp; 902 PGRP_LOCK(pg); 903 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 904 sigio, sio_pgsigio); 905 PGRP_UNLOCK(pg); 906 } else { 907 struct proc *p = (sigio)->sio_proc; 908 PROC_LOCK(p); 909 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 910 sigio, sio_pgsigio); 911 PROC_UNLOCK(p); 912 } 913 SIGIO_UNLOCK(); 914 crfree(sigio->sio_ucred); 915 free(sigio, M_SIGIO); 916 } 917 918 /* 919 * Free a list of sigio structures. 920 * We only need to lock the SIGIO_LOCK because we have made ourselves 921 * inaccessible to callers of fsetown and therefore do not need to lock 922 * the proc or pgrp struct for the list manipulation. 923 */ 924 void 925 funsetownlst(struct sigiolst *sigiolst) 926 { 927 struct proc *p; 928 struct pgrp *pg; 929 struct sigio *sigio; 930 931 sigio = SLIST_FIRST(sigiolst); 932 if (sigio == NULL) 933 return; 934 p = NULL; 935 pg = NULL; 936 937 /* 938 * Every entry of the list should belong 939 * to a single proc or pgrp. 940 */ 941 if (sigio->sio_pgid < 0) { 942 pg = sigio->sio_pgrp; 943 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 944 } else /* if (sigio->sio_pgid > 0) */ { 945 p = sigio->sio_proc; 946 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 947 } 948 949 SIGIO_LOCK(); 950 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 951 *(sigio->sio_myref) = NULL; 952 if (pg != NULL) { 953 KASSERT(sigio->sio_pgid < 0, 954 ("Proc sigio in pgrp sigio list")); 955 KASSERT(sigio->sio_pgrp == pg, 956 ("Bogus pgrp in sigio list")); 957 PGRP_LOCK(pg); 958 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 959 sio_pgsigio); 960 PGRP_UNLOCK(pg); 961 } else /* if (p != NULL) */ { 962 KASSERT(sigio->sio_pgid > 0, 963 ("Pgrp sigio in proc sigio list")); 964 KASSERT(sigio->sio_proc == p, 965 ("Bogus proc in sigio list")); 966 PROC_LOCK(p); 967 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 968 sio_pgsigio); 969 PROC_UNLOCK(p); 970 } 971 SIGIO_UNLOCK(); 972 crfree(sigio->sio_ucred); 973 free(sigio, M_SIGIO); 974 SIGIO_LOCK(); 975 } 976 SIGIO_UNLOCK(); 977 } 978 979 /* 980 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 981 * 982 * After permission checking, add a sigio structure to the sigio list for 983 * the process or process group. 984 */ 985 int 986 fsetown(pid_t pgid, struct sigio **sigiop) 987 { 988 struct proc *proc; 989 struct pgrp *pgrp; 990 struct sigio *sigio; 991 int ret; 992 993 if (pgid == 0) { 994 funsetown(sigiop); 995 return (0); 996 } 997 998 ret = 0; 999 1000 /* Allocate and fill in the new sigio out of locks. */ 1001 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1002 sigio->sio_pgid = pgid; 1003 sigio->sio_ucred = crhold(curthread->td_ucred); 1004 sigio->sio_myref = sigiop; 1005 1006 sx_slock(&proctree_lock); 1007 if (pgid > 0) { 1008 proc = pfind(pgid); 1009 if (proc == NULL) { 1010 ret = ESRCH; 1011 goto fail; 1012 } 1013 1014 /* 1015 * Policy - Don't allow a process to FSETOWN a process 1016 * in another session. 1017 * 1018 * Remove this test to allow maximum flexibility or 1019 * restrict FSETOWN to the current process or process 1020 * group for maximum safety. 1021 */ 1022 PROC_UNLOCK(proc); 1023 if (proc->p_session != curthread->td_proc->p_session) { 1024 ret = EPERM; 1025 goto fail; 1026 } 1027 1028 pgrp = NULL; 1029 } else /* if (pgid < 0) */ { 1030 pgrp = pgfind(-pgid); 1031 if (pgrp == NULL) { 1032 ret = ESRCH; 1033 goto fail; 1034 } 1035 PGRP_UNLOCK(pgrp); 1036 1037 /* 1038 * Policy - Don't allow a process to FSETOWN a process 1039 * in another session. 1040 * 1041 * Remove this test to allow maximum flexibility or 1042 * restrict FSETOWN to the current process or process 1043 * group for maximum safety. 1044 */ 1045 if (pgrp->pg_session != curthread->td_proc->p_session) { 1046 ret = EPERM; 1047 goto fail; 1048 } 1049 1050 proc = NULL; 1051 } 1052 funsetown(sigiop); 1053 if (pgid > 0) { 1054 PROC_LOCK(proc); 1055 /* 1056 * Since funsetownlst() is called without the proctree 1057 * locked, we need to check for P_WEXIT. 1058 * XXX: is ESRCH correct? 1059 */ 1060 if ((proc->p_flag & P_WEXIT) != 0) { 1061 PROC_UNLOCK(proc); 1062 ret = ESRCH; 1063 goto fail; 1064 } 1065 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1066 sigio->sio_proc = proc; 1067 PROC_UNLOCK(proc); 1068 } else { 1069 PGRP_LOCK(pgrp); 1070 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1071 sigio->sio_pgrp = pgrp; 1072 PGRP_UNLOCK(pgrp); 1073 } 1074 sx_sunlock(&proctree_lock); 1075 SIGIO_LOCK(); 1076 *sigiop = sigio; 1077 SIGIO_UNLOCK(); 1078 return (0); 1079 1080 fail: 1081 sx_sunlock(&proctree_lock); 1082 crfree(sigio->sio_ucred); 1083 free(sigio, M_SIGIO); 1084 return (ret); 1085 } 1086 1087 /* 1088 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1089 */ 1090 pid_t 1091 fgetown(sigiop) 1092 struct sigio **sigiop; 1093 { 1094 pid_t pgid; 1095 1096 SIGIO_LOCK(); 1097 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1098 SIGIO_UNLOCK(); 1099 return (pgid); 1100 } 1101 1102 /* 1103 * Function drops the filedesc lock on return. 1104 */ 1105 static int 1106 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1107 int holdleaders) 1108 { 1109 int error; 1110 1111 FILEDESC_XLOCK_ASSERT(fdp); 1112 1113 if (holdleaders) { 1114 if (td->td_proc->p_fdtol != NULL) { 1115 /* 1116 * Ask fdfree() to sleep to ensure that all relevant 1117 * process leaders can be traversed in closef(). 1118 */ 1119 fdp->fd_holdleaderscount++; 1120 } else { 1121 holdleaders = 0; 1122 } 1123 } 1124 1125 /* 1126 * We now hold the fp reference that used to be owned by the 1127 * descriptor array. We have to unlock the FILEDESC *AFTER* 1128 * knote_fdclose to prevent a race of the fd getting opened, a knote 1129 * added, and deleteing a knote for the new fd. 1130 */ 1131 knote_fdclose(td, fd); 1132 1133 /* 1134 * We need to notify mqueue if the object is of type mqueue. 1135 */ 1136 if (fp->f_type == DTYPE_MQUEUE) 1137 mq_fdclose(td, fd, fp); 1138 FILEDESC_XUNLOCK(fdp); 1139 1140 error = closef(fp, td); 1141 if (holdleaders) { 1142 FILEDESC_XLOCK(fdp); 1143 fdp->fd_holdleaderscount--; 1144 if (fdp->fd_holdleaderscount == 0 && 1145 fdp->fd_holdleaderswakeup != 0) { 1146 fdp->fd_holdleaderswakeup = 0; 1147 wakeup(&fdp->fd_holdleaderscount); 1148 } 1149 FILEDESC_XUNLOCK(fdp); 1150 } 1151 return (error); 1152 } 1153 1154 /* 1155 * Close a file descriptor. 1156 */ 1157 #ifndef _SYS_SYSPROTO_H_ 1158 struct close_args { 1159 int fd; 1160 }; 1161 #endif 1162 /* ARGSUSED */ 1163 int 1164 sys_close(td, uap) 1165 struct thread *td; 1166 struct close_args *uap; 1167 { 1168 1169 return (kern_close(td, uap->fd)); 1170 } 1171 1172 int 1173 kern_close(td, fd) 1174 struct thread *td; 1175 int fd; 1176 { 1177 struct filedesc *fdp; 1178 struct file *fp; 1179 1180 fdp = td->td_proc->p_fd; 1181 1182 AUDIT_SYSCLOSE(td, fd); 1183 1184 FILEDESC_XLOCK(fdp); 1185 if ((fp = fget_locked(fdp, fd)) == NULL) { 1186 FILEDESC_XUNLOCK(fdp); 1187 return (EBADF); 1188 } 1189 fdfree(fdp, fd); 1190 1191 /* closefp() drops the FILEDESC lock for us. */ 1192 return (closefp(fdp, fd, fp, td, 1)); 1193 } 1194 1195 /* 1196 * Close open file descriptors. 1197 */ 1198 #ifndef _SYS_SYSPROTO_H_ 1199 struct closefrom_args { 1200 int lowfd; 1201 }; 1202 #endif 1203 /* ARGSUSED */ 1204 int 1205 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1206 { 1207 struct filedesc *fdp; 1208 int fd; 1209 1210 fdp = td->td_proc->p_fd; 1211 AUDIT_ARG_FD(uap->lowfd); 1212 1213 /* 1214 * Treat negative starting file descriptor values identical to 1215 * closefrom(0) which closes all files. 1216 */ 1217 if (uap->lowfd < 0) 1218 uap->lowfd = 0; 1219 FILEDESC_SLOCK(fdp); 1220 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) { 1221 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1222 FILEDESC_SUNLOCK(fdp); 1223 (void)kern_close(td, fd); 1224 FILEDESC_SLOCK(fdp); 1225 } 1226 } 1227 FILEDESC_SUNLOCK(fdp); 1228 return (0); 1229 } 1230 1231 #if defined(COMPAT_43) 1232 /* 1233 * Return status information about a file descriptor. 1234 */ 1235 #ifndef _SYS_SYSPROTO_H_ 1236 struct ofstat_args { 1237 int fd; 1238 struct ostat *sb; 1239 }; 1240 #endif 1241 /* ARGSUSED */ 1242 int 1243 ofstat(struct thread *td, struct ofstat_args *uap) 1244 { 1245 struct ostat oub; 1246 struct stat ub; 1247 int error; 1248 1249 error = kern_fstat(td, uap->fd, &ub); 1250 if (error == 0) { 1251 cvtstat(&ub, &oub); 1252 error = copyout(&oub, uap->sb, sizeof(oub)); 1253 } 1254 return (error); 1255 } 1256 #endif /* COMPAT_43 */ 1257 1258 /* 1259 * Return status information about a file descriptor. 1260 */ 1261 #ifndef _SYS_SYSPROTO_H_ 1262 struct fstat_args { 1263 int fd; 1264 struct stat *sb; 1265 }; 1266 #endif 1267 /* ARGSUSED */ 1268 int 1269 sys_fstat(struct thread *td, struct fstat_args *uap) 1270 { 1271 struct stat ub; 1272 int error; 1273 1274 error = kern_fstat(td, uap->fd, &ub); 1275 if (error == 0) 1276 error = copyout(&ub, uap->sb, sizeof(ub)); 1277 return (error); 1278 } 1279 1280 int 1281 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1282 { 1283 struct file *fp; 1284 int error; 1285 1286 AUDIT_ARG_FD(fd); 1287 1288 if ((error = fget(td, fd, CAP_FSTAT, &fp)) != 0) 1289 return (error); 1290 1291 AUDIT_ARG_FILE(td->td_proc, fp); 1292 1293 error = fo_stat(fp, sbp, td->td_ucred, td); 1294 fdrop(fp, td); 1295 #ifdef KTRACE 1296 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1297 ktrstat(sbp); 1298 #endif 1299 return (error); 1300 } 1301 1302 /* 1303 * Return status information about a file descriptor. 1304 */ 1305 #ifndef _SYS_SYSPROTO_H_ 1306 struct nfstat_args { 1307 int fd; 1308 struct nstat *sb; 1309 }; 1310 #endif 1311 /* ARGSUSED */ 1312 int 1313 sys_nfstat(struct thread *td, struct nfstat_args *uap) 1314 { 1315 struct nstat nub; 1316 struct stat ub; 1317 int error; 1318 1319 error = kern_fstat(td, uap->fd, &ub); 1320 if (error == 0) { 1321 cvtnstat(&ub, &nub); 1322 error = copyout(&nub, uap->sb, sizeof(nub)); 1323 } 1324 return (error); 1325 } 1326 1327 /* 1328 * Return pathconf information about a file descriptor. 1329 */ 1330 #ifndef _SYS_SYSPROTO_H_ 1331 struct fpathconf_args { 1332 int fd; 1333 int name; 1334 }; 1335 #endif 1336 /* ARGSUSED */ 1337 int 1338 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1339 { 1340 struct file *fp; 1341 struct vnode *vp; 1342 int error; 1343 1344 if ((error = fget(td, uap->fd, CAP_FPATHCONF, &fp)) != 0) 1345 return (error); 1346 1347 /* If asynchronous I/O is available, it works for all descriptors. */ 1348 if (uap->name == _PC_ASYNC_IO) { 1349 td->td_retval[0] = async_io_version; 1350 goto out; 1351 } 1352 vp = fp->f_vnode; 1353 if (vp != NULL) { 1354 vn_lock(vp, LK_SHARED | LK_RETRY); 1355 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1356 VOP_UNLOCK(vp, 0); 1357 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1358 if (uap->name != _PC_PIPE_BUF) { 1359 error = EINVAL; 1360 } else { 1361 td->td_retval[0] = PIPE_BUF; 1362 error = 0; 1363 } 1364 } else { 1365 error = EOPNOTSUPP; 1366 } 1367 out: 1368 fdrop(fp, td); 1369 return (error); 1370 } 1371 1372 /* 1373 * Initialize filecaps structure. 1374 */ 1375 void 1376 filecaps_init(struct filecaps *fcaps) 1377 { 1378 1379 bzero(fcaps, sizeof(*fcaps)); 1380 fcaps->fc_nioctls = -1; 1381 } 1382 1383 /* 1384 * Copy filecaps structure allocating memory for ioctls array if needed. 1385 */ 1386 void 1387 filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1388 { 1389 size_t size; 1390 1391 *dst = *src; 1392 if (src->fc_ioctls != NULL) { 1393 KASSERT(src->fc_nioctls > 0, 1394 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1395 1396 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1397 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1398 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1399 } 1400 } 1401 1402 /* 1403 * Move filecaps structure to the new place and clear the old place. 1404 */ 1405 void 1406 filecaps_move(struct filecaps *src, struct filecaps *dst) 1407 { 1408 1409 *dst = *src; 1410 bzero(src, sizeof(*src)); 1411 } 1412 1413 /* 1414 * Fill the given filecaps structure with full rights. 1415 */ 1416 static void 1417 filecaps_fill(struct filecaps *fcaps) 1418 { 1419 1420 fcaps->fc_rights = CAP_ALL; 1421 fcaps->fc_ioctls = NULL; 1422 fcaps->fc_nioctls = -1; 1423 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1424 } 1425 1426 /* 1427 * Free memory allocated within filecaps structure. 1428 */ 1429 void 1430 filecaps_free(struct filecaps *fcaps) 1431 { 1432 1433 free(fcaps->fc_ioctls, M_FILECAPS); 1434 bzero(fcaps, sizeof(*fcaps)); 1435 } 1436 1437 /* 1438 * Validate the given filecaps structure. 1439 */ 1440 static void 1441 filecaps_validate(const struct filecaps *fcaps, const char *func) 1442 { 1443 1444 KASSERT((fcaps->fc_rights & ~CAP_MASK_VALID) == 0, 1445 ("%s: invalid rights", func)); 1446 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1447 ("%s: invalid fcntls", func)); 1448 KASSERT(fcaps->fc_fcntls == 0 || (fcaps->fc_rights & CAP_FCNTL) != 0, 1449 ("%s: fcntls without CAP_FCNTL", func)); 1450 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1451 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1452 ("%s: invalid ioctls", func)); 1453 KASSERT(fcaps->fc_nioctls == 0 || (fcaps->fc_rights & CAP_IOCTL) != 0, 1454 ("%s: ioctls without CAP_IOCTL", func)); 1455 } 1456 1457 /* 1458 * Grow the file table to accomodate (at least) nfd descriptors. 1459 */ 1460 static void 1461 fdgrowtable(struct filedesc *fdp, int nfd) 1462 { 1463 struct filedesc0 *fdp0; 1464 struct freetable *ft; 1465 struct filedescent *ntable; 1466 struct filedescent *otable; 1467 int nnfiles, onfiles; 1468 NDSLOTTYPE *nmap, *omap; 1469 1470 FILEDESC_XLOCK_ASSERT(fdp); 1471 1472 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1473 1474 /* save old values */ 1475 onfiles = fdp->fd_nfiles; 1476 otable = fdp->fd_ofiles; 1477 omap = fdp->fd_map; 1478 1479 /* compute the size of the new table */ 1480 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1481 if (nnfiles <= onfiles) 1482 /* the table is already large enough */ 1483 return; 1484 1485 /* 1486 * Allocate a new table and map. We need enough space for the 1487 * file entries themselves and the struct freetable we will use 1488 * when we decommission the table and place it on the freelist. 1489 * We place the struct freetable in the middle so we don't have 1490 * to worry about padding. 1491 */ 1492 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1493 M_FILEDESC, M_ZERO | M_WAITOK); 1494 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1495 M_ZERO | M_WAITOK); 1496 1497 /* copy the old data over and point at the new tables */ 1498 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1499 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1500 1501 /* update the pointers and counters */ 1502 fdp->fd_nfiles = nnfiles; 1503 memcpy(ntable, otable, onfiles * sizeof(ntable[0])); 1504 fdp->fd_ofiles = ntable; 1505 fdp->fd_map = nmap; 1506 1507 /* 1508 * Do not free the old file table, as some threads may still 1509 * reference entries within it. Instead, place it on a freelist 1510 * which will be processed when the struct filedesc is released. 1511 * 1512 * Do, however, free the old map. 1513 * 1514 * Note that if onfiles == NDFILE, we're dealing with the original 1515 * static allocation contained within (struct filedesc0 *)fdp, 1516 * which must not be freed. 1517 */ 1518 if (onfiles > NDFILE) { 1519 ft = (struct freetable *)&otable[onfiles]; 1520 fdp0 = (struct filedesc0 *)fdp; 1521 ft->ft_table = otable; 1522 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1523 free(omap, M_FILEDESC); 1524 } 1525 } 1526 1527 /* 1528 * Allocate a file descriptor for the process. 1529 */ 1530 int 1531 fdalloc(struct thread *td, int minfd, int *result) 1532 { 1533 struct proc *p = td->td_proc; 1534 struct filedesc *fdp = p->p_fd; 1535 int fd = -1, maxfd, allocfd; 1536 #ifdef RACCT 1537 int error; 1538 #endif 1539 1540 FILEDESC_XLOCK_ASSERT(fdp); 1541 1542 if (fdp->fd_freefile > minfd) 1543 minfd = fdp->fd_freefile; 1544 1545 PROC_LOCK(p); 1546 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 1547 PROC_UNLOCK(p); 1548 1549 /* 1550 * Search the bitmap for a free descriptor starting at minfd. 1551 * If none is found, grow the file table. 1552 */ 1553 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1554 if (fd >= maxfd) 1555 return (EMFILE); 1556 if (fd >= fdp->fd_nfiles) { 1557 allocfd = min(fd * 2, maxfd); 1558 #ifdef RACCT 1559 PROC_LOCK(p); 1560 error = racct_set(p, RACCT_NOFILE, allocfd); 1561 PROC_UNLOCK(p); 1562 if (error != 0) 1563 return (EMFILE); 1564 #endif 1565 /* 1566 * fd is already equal to first free descriptor >= minfd, so 1567 * we only need to grow the table and we are done. 1568 */ 1569 fdgrowtable(fdp, allocfd); 1570 } 1571 1572 /* 1573 * Perform some sanity checks, then mark the file descriptor as 1574 * used and return it to the caller. 1575 */ 1576 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1577 ("invalid descriptor %d", fd)); 1578 KASSERT(!fdisused(fdp, fd), 1579 ("fd_first_free() returned non-free descriptor")); 1580 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1581 ("file descriptor isn't free")); 1582 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1583 fdused(fdp, fd); 1584 *result = fd; 1585 return (0); 1586 } 1587 1588 /* 1589 * Allocate n file descriptors for the process. 1590 */ 1591 int 1592 fdallocn(struct thread *td, int minfd, int *fds, int n) 1593 { 1594 struct proc *p = td->td_proc; 1595 struct filedesc *fdp = p->p_fd; 1596 int i; 1597 1598 FILEDESC_XLOCK_ASSERT(fdp); 1599 1600 if (!fdavail(td, n)) 1601 return (EMFILE); 1602 1603 for (i = 0; i < n; i++) 1604 if (fdalloc(td, 0, &fds[i]) != 0) 1605 break; 1606 1607 if (i < n) { 1608 for (i--; i >= 0; i--) 1609 fdunused(fdp, fds[i]); 1610 return (EMFILE); 1611 } 1612 1613 return (0); 1614 } 1615 1616 /* 1617 * Check to see whether n user file descriptors are available to the process 1618 * p. 1619 */ 1620 int 1621 fdavail(struct thread *td, int n) 1622 { 1623 struct proc *p = td->td_proc; 1624 struct filedesc *fdp = td->td_proc->p_fd; 1625 int i, lim, last; 1626 1627 FILEDESC_LOCK_ASSERT(fdp); 1628 1629 /* 1630 * XXX: This is only called from uipc_usrreq.c:unp_externalize(); 1631 * call racct_add() from there instead of dealing with containers 1632 * here. 1633 */ 1634 PROC_LOCK(p); 1635 lim = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 1636 PROC_UNLOCK(p); 1637 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) 1638 return (1); 1639 last = min(fdp->fd_nfiles, lim); 1640 for (i = fdp->fd_freefile; i < last; i++) { 1641 if (fdp->fd_ofiles[i].fde_file == NULL && --n <= 0) 1642 return (1); 1643 } 1644 return (0); 1645 } 1646 1647 /* 1648 * Create a new open file structure and allocate a file decriptor for the 1649 * process that refers to it. We add one reference to the file for the 1650 * descriptor table and one reference for resultfp. This is to prevent us 1651 * being preempted and the entry in the descriptor table closed after we 1652 * release the FILEDESC lock. 1653 */ 1654 int 1655 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1656 { 1657 struct file *fp; 1658 int error, fd; 1659 1660 error = falloc_noinstall(td, &fp); 1661 if (error) 1662 return (error); /* no reference held on error */ 1663 1664 error = finstall(td, fp, &fd, flags, NULL); 1665 if (error) { 1666 fdrop(fp, td); /* one reference (fp only) */ 1667 return (error); 1668 } 1669 1670 if (resultfp != NULL) 1671 *resultfp = fp; /* copy out result */ 1672 else 1673 fdrop(fp, td); /* release local reference */ 1674 1675 if (resultfd != NULL) 1676 *resultfd = fd; 1677 1678 return (0); 1679 } 1680 1681 /* 1682 * Create a new open file structure without allocating a file descriptor. 1683 */ 1684 int 1685 falloc_noinstall(struct thread *td, struct file **resultfp) 1686 { 1687 struct file *fp; 1688 int maxuserfiles = maxfiles - (maxfiles / 20); 1689 static struct timeval lastfail; 1690 static int curfail; 1691 1692 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1693 1694 if ((openfiles >= maxuserfiles && 1695 priv_check(td, PRIV_MAXFILES) != 0) || 1696 openfiles >= maxfiles) { 1697 if (ppsratecheck(&lastfail, &curfail, 1)) { 1698 printf("kern.maxfiles limit exceeded by uid %i, " 1699 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1700 } 1701 return (ENFILE); 1702 } 1703 atomic_add_int(&openfiles, 1); 1704 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1705 refcount_init(&fp->f_count, 1); 1706 fp->f_cred = crhold(td->td_ucred); 1707 fp->f_ops = &badfileops; 1708 fp->f_data = NULL; 1709 fp->f_vnode = NULL; 1710 *resultfp = fp; 1711 return (0); 1712 } 1713 1714 /* 1715 * Install a file in a file descriptor table. 1716 */ 1717 int 1718 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1719 struct filecaps *fcaps) 1720 { 1721 struct filedesc *fdp = td->td_proc->p_fd; 1722 struct filedescent *fde; 1723 int error; 1724 1725 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1726 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1727 if (fcaps != NULL) 1728 filecaps_validate(fcaps, __func__); 1729 1730 FILEDESC_XLOCK(fdp); 1731 if ((error = fdalloc(td, 0, fd))) { 1732 FILEDESC_XUNLOCK(fdp); 1733 return (error); 1734 } 1735 fhold(fp); 1736 fde = &fdp->fd_ofiles[*fd]; 1737 fde->fde_file = fp; 1738 if ((flags & O_CLOEXEC) != 0) 1739 fde->fde_flags |= UF_EXCLOSE; 1740 if (fcaps != NULL) 1741 filecaps_move(fcaps, &fde->fde_caps); 1742 else 1743 filecaps_fill(&fde->fde_caps); 1744 FILEDESC_XUNLOCK(fdp); 1745 return (0); 1746 } 1747 1748 /* 1749 * Build a new filedesc structure from another. 1750 * Copy the current, root, and jail root vnode references. 1751 */ 1752 struct filedesc * 1753 fdinit(struct filedesc *fdp) 1754 { 1755 struct filedesc0 *newfdp; 1756 1757 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1758 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1759 if (fdp != NULL) { 1760 FILEDESC_XLOCK(fdp); 1761 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1762 if (newfdp->fd_fd.fd_cdir) 1763 VREF(newfdp->fd_fd.fd_cdir); 1764 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1765 if (newfdp->fd_fd.fd_rdir) 1766 VREF(newfdp->fd_fd.fd_rdir); 1767 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1768 if (newfdp->fd_fd.fd_jdir) 1769 VREF(newfdp->fd_fd.fd_jdir); 1770 FILEDESC_XUNLOCK(fdp); 1771 } 1772 1773 /* Create the file descriptor table. */ 1774 newfdp->fd_fd.fd_refcnt = 1; 1775 newfdp->fd_fd.fd_holdcnt = 1; 1776 newfdp->fd_fd.fd_cmask = CMASK; 1777 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1778 newfdp->fd_fd.fd_nfiles = NDFILE; 1779 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1780 newfdp->fd_fd.fd_lastfile = -1; 1781 return (&newfdp->fd_fd); 1782 } 1783 1784 static struct filedesc * 1785 fdhold(struct proc *p) 1786 { 1787 struct filedesc *fdp; 1788 1789 mtx_lock(&fdesc_mtx); 1790 fdp = p->p_fd; 1791 if (fdp != NULL) 1792 fdp->fd_holdcnt++; 1793 mtx_unlock(&fdesc_mtx); 1794 return (fdp); 1795 } 1796 1797 static void 1798 fddrop(struct filedesc *fdp) 1799 { 1800 struct filedesc0 *fdp0; 1801 struct freetable *ft; 1802 int i; 1803 1804 mtx_lock(&fdesc_mtx); 1805 i = --fdp->fd_holdcnt; 1806 mtx_unlock(&fdesc_mtx); 1807 if (i > 0) 1808 return; 1809 1810 FILEDESC_LOCK_DESTROY(fdp); 1811 fdp0 = (struct filedesc0 *)fdp; 1812 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1813 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1814 free(ft->ft_table, M_FILEDESC); 1815 } 1816 free(fdp, M_FILEDESC); 1817 } 1818 1819 /* 1820 * Share a filedesc structure. 1821 */ 1822 struct filedesc * 1823 fdshare(struct filedesc *fdp) 1824 { 1825 1826 FILEDESC_XLOCK(fdp); 1827 fdp->fd_refcnt++; 1828 FILEDESC_XUNLOCK(fdp); 1829 return (fdp); 1830 } 1831 1832 /* 1833 * Unshare a filedesc structure, if necessary by making a copy 1834 */ 1835 void 1836 fdunshare(struct proc *p, struct thread *td) 1837 { 1838 1839 FILEDESC_XLOCK(p->p_fd); 1840 if (p->p_fd->fd_refcnt > 1) { 1841 struct filedesc *tmp; 1842 1843 FILEDESC_XUNLOCK(p->p_fd); 1844 tmp = fdcopy(p->p_fd); 1845 fdescfree(td); 1846 p->p_fd = tmp; 1847 } else 1848 FILEDESC_XUNLOCK(p->p_fd); 1849 } 1850 1851 /* 1852 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1853 * this is to ease callers, not catch errors. 1854 */ 1855 struct filedesc * 1856 fdcopy(struct filedesc *fdp) 1857 { 1858 struct filedesc *newfdp; 1859 struct filedescent *nfde, *ofde; 1860 int i; 1861 1862 /* Certain daemons might not have file descriptors. */ 1863 if (fdp == NULL) 1864 return (NULL); 1865 1866 newfdp = fdinit(fdp); 1867 FILEDESC_SLOCK(fdp); 1868 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1869 FILEDESC_SUNLOCK(fdp); 1870 FILEDESC_XLOCK(newfdp); 1871 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1872 FILEDESC_XUNLOCK(newfdp); 1873 FILEDESC_SLOCK(fdp); 1874 } 1875 /* copy all passable descriptors (i.e. not kqueue) */ 1876 newfdp->fd_freefile = -1; 1877 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1878 ofde = &fdp->fd_ofiles[i]; 1879 if (fdisused(fdp, i) && 1880 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1881 ofde->fde_file->f_ops != &badfileops) { 1882 nfde = &newfdp->fd_ofiles[i]; 1883 *nfde = *ofde; 1884 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1885 fhold(nfde->fde_file); 1886 newfdp->fd_lastfile = i; 1887 } else { 1888 if (newfdp->fd_freefile == -1) 1889 newfdp->fd_freefile = i; 1890 } 1891 } 1892 newfdp->fd_cmask = fdp->fd_cmask; 1893 FILEDESC_SUNLOCK(fdp); 1894 FILEDESC_XLOCK(newfdp); 1895 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1896 if (newfdp->fd_ofiles[i].fde_file != NULL) 1897 fdused(newfdp, i); 1898 } 1899 if (newfdp->fd_freefile == -1) 1900 newfdp->fd_freefile = i; 1901 FILEDESC_XUNLOCK(newfdp); 1902 return (newfdp); 1903 } 1904 1905 /* 1906 * Release a filedesc structure. 1907 */ 1908 void 1909 fdescfree(struct thread *td) 1910 { 1911 struct filedesc *fdp; 1912 int i; 1913 struct filedesc_to_leader *fdtol; 1914 struct file *fp; 1915 struct vnode *cdir, *jdir, *rdir, *vp; 1916 struct flock lf; 1917 1918 /* Certain daemons might not have file descriptors. */ 1919 fdp = td->td_proc->p_fd; 1920 if (fdp == NULL) 1921 return; 1922 1923 #ifdef RACCT 1924 PROC_LOCK(td->td_proc); 1925 racct_set(td->td_proc, RACCT_NOFILE, 0); 1926 PROC_UNLOCK(td->td_proc); 1927 #endif 1928 1929 /* Check for special need to clear POSIX style locks */ 1930 fdtol = td->td_proc->p_fdtol; 1931 if (fdtol != NULL) { 1932 FILEDESC_XLOCK(fdp); 1933 KASSERT(fdtol->fdl_refcount > 0, 1934 ("filedesc_to_refcount botch: fdl_refcount=%d", 1935 fdtol->fdl_refcount)); 1936 if (fdtol->fdl_refcount == 1 && 1937 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1938 for (i = 0; i <= fdp->fd_lastfile; i++) { 1939 fp = fdp->fd_ofiles[i].fde_file; 1940 if (fp == NULL || fp->f_type != DTYPE_VNODE) 1941 continue; 1942 fhold(fp); 1943 FILEDESC_XUNLOCK(fdp); 1944 lf.l_whence = SEEK_SET; 1945 lf.l_start = 0; 1946 lf.l_len = 0; 1947 lf.l_type = F_UNLCK; 1948 vp = fp->f_vnode; 1949 (void) VOP_ADVLOCK(vp, 1950 (caddr_t)td->td_proc->p_leader, F_UNLCK, 1951 &lf, F_POSIX); 1952 FILEDESC_XLOCK(fdp); 1953 fdrop(fp, td); 1954 } 1955 } 1956 retry: 1957 if (fdtol->fdl_refcount == 1) { 1958 if (fdp->fd_holdleaderscount > 0 && 1959 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1960 /* 1961 * close() or do_dup() has cleared a reference 1962 * in a shared file descriptor table. 1963 */ 1964 fdp->fd_holdleaderswakeup = 1; 1965 sx_sleep(&fdp->fd_holdleaderscount, 1966 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 1967 goto retry; 1968 } 1969 if (fdtol->fdl_holdcount > 0) { 1970 /* 1971 * Ensure that fdtol->fdl_leader remains 1972 * valid in closef(). 1973 */ 1974 fdtol->fdl_wakeup = 1; 1975 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 1976 "fdlhold", 0); 1977 goto retry; 1978 } 1979 } 1980 fdtol->fdl_refcount--; 1981 if (fdtol->fdl_refcount == 0 && 1982 fdtol->fdl_holdcount == 0) { 1983 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 1984 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 1985 } else 1986 fdtol = NULL; 1987 td->td_proc->p_fdtol = NULL; 1988 FILEDESC_XUNLOCK(fdp); 1989 if (fdtol != NULL) 1990 free(fdtol, M_FILEDESC_TO_LEADER); 1991 } 1992 FILEDESC_XLOCK(fdp); 1993 i = --fdp->fd_refcnt; 1994 FILEDESC_XUNLOCK(fdp); 1995 if (i > 0) 1996 return; 1997 1998 for (i = 0; i <= fdp->fd_lastfile; i++) { 1999 fp = fdp->fd_ofiles[i].fde_file; 2000 if (fp != NULL) { 2001 FILEDESC_XLOCK(fdp); 2002 fdfree(fdp, i); 2003 FILEDESC_XUNLOCK(fdp); 2004 (void) closef(fp, td); 2005 } 2006 } 2007 FILEDESC_XLOCK(fdp); 2008 2009 /* XXX This should happen earlier. */ 2010 mtx_lock(&fdesc_mtx); 2011 td->td_proc->p_fd = NULL; 2012 mtx_unlock(&fdesc_mtx); 2013 2014 if (fdp->fd_nfiles > NDFILE) 2015 free(fdp->fd_ofiles, M_FILEDESC); 2016 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2017 free(fdp->fd_map, M_FILEDESC); 2018 2019 fdp->fd_nfiles = 0; 2020 2021 cdir = fdp->fd_cdir; 2022 fdp->fd_cdir = NULL; 2023 rdir = fdp->fd_rdir; 2024 fdp->fd_rdir = NULL; 2025 jdir = fdp->fd_jdir; 2026 fdp->fd_jdir = NULL; 2027 FILEDESC_XUNLOCK(fdp); 2028 2029 if (cdir != NULL) 2030 vrele(cdir); 2031 if (rdir != NULL) 2032 vrele(rdir); 2033 if (jdir != NULL) 2034 vrele(jdir); 2035 2036 fddrop(fdp); 2037 } 2038 2039 /* 2040 * For setugid programs, we don't want to people to use that setugidness 2041 * to generate error messages which write to a file which otherwise would 2042 * otherwise be off-limits to the process. We check for filesystems where 2043 * the vnode can change out from under us after execve (like [lin]procfs). 2044 * 2045 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2046 * sufficient. We also don't check for setugidness since we know we are. 2047 */ 2048 static int 2049 is_unsafe(struct file *fp) 2050 { 2051 if (fp->f_type == DTYPE_VNODE) { 2052 struct vnode *vp = fp->f_vnode; 2053 2054 if ((vp->v_vflag & VV_PROCDEP) != 0) 2055 return (1); 2056 } 2057 return (0); 2058 } 2059 2060 /* 2061 * Make this setguid thing safe, if at all possible. 2062 */ 2063 void 2064 setugidsafety(struct thread *td) 2065 { 2066 struct filedesc *fdp; 2067 struct file *fp; 2068 int i; 2069 2070 /* Certain daemons might not have file descriptors. */ 2071 fdp = td->td_proc->p_fd; 2072 if (fdp == NULL) 2073 return; 2074 2075 /* 2076 * Note: fdp->fd_ofiles may be reallocated out from under us while 2077 * we are blocked in a close. Be careful! 2078 */ 2079 FILEDESC_XLOCK(fdp); 2080 for (i = 0; i <= fdp->fd_lastfile; i++) { 2081 if (i > 2) 2082 break; 2083 fp = fdp->fd_ofiles[i].fde_file; 2084 if (fp != NULL && is_unsafe(fp)) { 2085 knote_fdclose(td, i); 2086 /* 2087 * NULL-out descriptor prior to close to avoid 2088 * a race while close blocks. 2089 */ 2090 fdfree(fdp, i); 2091 FILEDESC_XUNLOCK(fdp); 2092 (void) closef(fp, td); 2093 FILEDESC_XLOCK(fdp); 2094 } 2095 } 2096 FILEDESC_XUNLOCK(fdp); 2097 } 2098 2099 /* 2100 * If a specific file object occupies a specific file descriptor, close the 2101 * file descriptor entry and drop a reference on the file object. This is a 2102 * convenience function to handle a subsequent error in a function that calls 2103 * falloc() that handles the race that another thread might have closed the 2104 * file descriptor out from under the thread creating the file object. 2105 */ 2106 void 2107 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2108 { 2109 2110 FILEDESC_XLOCK(fdp); 2111 if (fdp->fd_ofiles[idx].fde_file == fp) { 2112 fdfree(fdp, idx); 2113 FILEDESC_XUNLOCK(fdp); 2114 fdrop(fp, td); 2115 } else 2116 FILEDESC_XUNLOCK(fdp); 2117 } 2118 2119 /* 2120 * Close any files on exec? 2121 */ 2122 void 2123 fdcloseexec(struct thread *td) 2124 { 2125 struct filedesc *fdp; 2126 struct filedescent *fde; 2127 struct file *fp; 2128 int i; 2129 2130 /* Certain daemons might not have file descriptors. */ 2131 fdp = td->td_proc->p_fd; 2132 if (fdp == NULL) 2133 return; 2134 2135 /* 2136 * We cannot cache fd_ofiles since operations 2137 * may block and rip them out from under us. 2138 */ 2139 FILEDESC_XLOCK(fdp); 2140 for (i = 0; i <= fdp->fd_lastfile; i++) { 2141 fde = &fdp->fd_ofiles[i]; 2142 fp = fde->fde_file; 2143 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2144 (fde->fde_flags & UF_EXCLOSE))) { 2145 fdfree(fdp, i); 2146 (void) closefp(fdp, i, fp, td, 0); 2147 /* closefp() drops the FILEDESC lock. */ 2148 FILEDESC_XLOCK(fdp); 2149 } 2150 } 2151 FILEDESC_XUNLOCK(fdp); 2152 } 2153 2154 /* 2155 * It is unsafe for set[ug]id processes to be started with file 2156 * descriptors 0..2 closed, as these descriptors are given implicit 2157 * significance in the Standard C library. fdcheckstd() will create a 2158 * descriptor referencing /dev/null for each of stdin, stdout, and 2159 * stderr that is not already open. 2160 */ 2161 int 2162 fdcheckstd(struct thread *td) 2163 { 2164 struct filedesc *fdp; 2165 register_t retval, save; 2166 int i, error, devnull; 2167 2168 fdp = td->td_proc->p_fd; 2169 if (fdp == NULL) 2170 return (0); 2171 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2172 devnull = -1; 2173 error = 0; 2174 for (i = 0; i < 3; i++) { 2175 if (fdp->fd_ofiles[i].fde_file != NULL) 2176 continue; 2177 if (devnull < 0) { 2178 save = td->td_retval[0]; 2179 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2180 O_RDWR, 0); 2181 devnull = td->td_retval[0]; 2182 td->td_retval[0] = save; 2183 if (error) 2184 break; 2185 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2186 } else { 2187 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2188 if (error != 0) 2189 break; 2190 } 2191 } 2192 return (error); 2193 } 2194 2195 /* 2196 * Internal form of close. Decrement reference count on file structure. 2197 * Note: td may be NULL when closing a file that was being passed in a 2198 * message. 2199 * 2200 * XXXRW: Giant is not required for the caller, but often will be held; this 2201 * makes it moderately likely the Giant will be recursed in the VFS case. 2202 */ 2203 int 2204 closef(struct file *fp, struct thread *td) 2205 { 2206 struct vnode *vp; 2207 struct flock lf; 2208 struct filedesc_to_leader *fdtol; 2209 struct filedesc *fdp; 2210 2211 /* 2212 * POSIX record locking dictates that any close releases ALL 2213 * locks owned by this process. This is handled by setting 2214 * a flag in the unlock to free ONLY locks obeying POSIX 2215 * semantics, and not to free BSD-style file locks. 2216 * If the descriptor was in a message, POSIX-style locks 2217 * aren't passed with the descriptor, and the thread pointer 2218 * will be NULL. Callers should be careful only to pass a 2219 * NULL thread pointer when there really is no owning 2220 * context that might have locks, or the locks will be 2221 * leaked. 2222 */ 2223 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2224 vp = fp->f_vnode; 2225 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2226 lf.l_whence = SEEK_SET; 2227 lf.l_start = 0; 2228 lf.l_len = 0; 2229 lf.l_type = F_UNLCK; 2230 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2231 F_UNLCK, &lf, F_POSIX); 2232 } 2233 fdtol = td->td_proc->p_fdtol; 2234 if (fdtol != NULL) { 2235 /* 2236 * Handle special case where file descriptor table is 2237 * shared between multiple process leaders. 2238 */ 2239 fdp = td->td_proc->p_fd; 2240 FILEDESC_XLOCK(fdp); 2241 for (fdtol = fdtol->fdl_next; 2242 fdtol != td->td_proc->p_fdtol; 2243 fdtol = fdtol->fdl_next) { 2244 if ((fdtol->fdl_leader->p_flag & 2245 P_ADVLOCK) == 0) 2246 continue; 2247 fdtol->fdl_holdcount++; 2248 FILEDESC_XUNLOCK(fdp); 2249 lf.l_whence = SEEK_SET; 2250 lf.l_start = 0; 2251 lf.l_len = 0; 2252 lf.l_type = F_UNLCK; 2253 vp = fp->f_vnode; 2254 (void) VOP_ADVLOCK(vp, 2255 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2256 F_POSIX); 2257 FILEDESC_XLOCK(fdp); 2258 fdtol->fdl_holdcount--; 2259 if (fdtol->fdl_holdcount == 0 && 2260 fdtol->fdl_wakeup != 0) { 2261 fdtol->fdl_wakeup = 0; 2262 wakeup(fdtol); 2263 } 2264 } 2265 FILEDESC_XUNLOCK(fdp); 2266 } 2267 } 2268 return (fdrop(fp, td)); 2269 } 2270 2271 /* 2272 * Initialize the file pointer with the specified properties. 2273 * 2274 * The ops are set with release semantics to be certain that the flags, type, 2275 * and data are visible when ops is. This is to prevent ops methods from being 2276 * called with bad data. 2277 */ 2278 void 2279 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2280 { 2281 fp->f_data = data; 2282 fp->f_flag = flag; 2283 fp->f_type = type; 2284 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2285 } 2286 2287 int 2288 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t needrights, 2289 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2290 { 2291 struct file *fp; 2292 u_int count; 2293 #ifdef CAPABILITIES 2294 cap_rights_t haverights; 2295 int error; 2296 #endif 2297 2298 if (fd < 0 || fd >= fdp->fd_nfiles) 2299 return (EBADF); 2300 /* 2301 * Fetch the descriptor locklessly. We avoid fdrop() races by 2302 * never raising a refcount above 0. To accomplish this we have 2303 * to use a cmpset loop rather than an atomic_add. The descriptor 2304 * must be re-verified once we acquire a reference to be certain 2305 * that the identity is still correct and we did not lose a race 2306 * due to preemption. 2307 */ 2308 for (;;) { 2309 fp = fdp->fd_ofiles[fd].fde_file; 2310 if (fp == NULL) 2311 return (EBADF); 2312 #ifdef CAPABILITIES 2313 haverights = cap_rights(fdp, fd); 2314 error = cap_check(haverights, needrights); 2315 if (error != 0) 2316 return (error); 2317 if ((needrights & CAP_FCNTL) != 0) { 2318 error = cap_fcntl_check(fdp, fd, needfcntl); 2319 if (error != 0) 2320 return (error); 2321 } 2322 #endif 2323 count = fp->f_count; 2324 if (count == 0) 2325 continue; 2326 /* 2327 * Use an acquire barrier to prevent caching of fd_ofiles 2328 * so it is refreshed for verification. 2329 */ 2330 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2331 continue; 2332 if (fp == fdp->fd_ofiles[fd].fde_file) 2333 break; 2334 fdrop(fp, curthread); 2335 } 2336 *fpp = fp; 2337 if (haverightsp != NULL) { 2338 #ifdef CAPABILITIES 2339 *haverightsp = haverights; 2340 #else 2341 *haverightsp = CAP_ALL; 2342 #endif 2343 } 2344 return (0); 2345 } 2346 2347 /* 2348 * Extract the file pointer associated with the specified descriptor for the 2349 * current user process. 2350 * 2351 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2352 * returned. 2353 * 2354 * File's rights will be checked against the capability rights mask. 2355 * 2356 * If an error occured the non-zero error is returned and *fpp is set to 2357 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2358 * responsible for fdrop(). 2359 */ 2360 static __inline int 2361 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2362 cap_rights_t needrights, u_char *maxprotp) 2363 { 2364 struct filedesc *fdp; 2365 struct file *fp; 2366 cap_rights_t haverights; 2367 int error; 2368 2369 *fpp = NULL; 2370 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2371 return (EBADF); 2372 if (maxprotp != NULL) 2373 needrights |= CAP_MMAP; 2374 error = fget_unlocked(fdp, fd, needrights, 0, &fp, &haverights); 2375 if (error != 0) 2376 return (error); 2377 if (fp->f_ops == &badfileops) { 2378 fdrop(fp, td); 2379 return (EBADF); 2380 } 2381 2382 #ifdef CAPABILITIES 2383 /* 2384 * If requested, convert capability rights to access flags. 2385 */ 2386 if (maxprotp != NULL) 2387 *maxprotp = cap_rights_to_vmprot(haverights); 2388 #else /* !CAPABILITIES */ 2389 if (maxprotp != NULL) 2390 *maxprotp = VM_PROT_ALL; 2391 #endif /* CAPABILITIES */ 2392 2393 /* 2394 * FREAD and FWRITE failure return EBADF as per POSIX. 2395 */ 2396 error = 0; 2397 switch (flags) { 2398 case FREAD: 2399 case FWRITE: 2400 if ((fp->f_flag & flags) == 0) 2401 error = EBADF; 2402 break; 2403 case FEXEC: 2404 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2405 ((fp->f_flag & FWRITE) != 0)) 2406 error = EBADF; 2407 break; 2408 case 0: 2409 break; 2410 default: 2411 KASSERT(0, ("wrong flags")); 2412 } 2413 2414 if (error != 0) { 2415 fdrop(fp, td); 2416 return (error); 2417 } 2418 2419 *fpp = fp; 2420 return (0); 2421 } 2422 2423 int 2424 fget(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) 2425 { 2426 2427 return(_fget(td, fd, fpp, 0, rights, NULL)); 2428 } 2429 2430 int 2431 fget_mmap(struct thread *td, int fd, cap_rights_t rights, u_char *maxprotp, 2432 struct file **fpp) 2433 { 2434 2435 return (_fget(td, fd, fpp, 0, rights, maxprotp)); 2436 } 2437 2438 int 2439 fget_read(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) 2440 { 2441 2442 return(_fget(td, fd, fpp, FREAD, rights, NULL)); 2443 } 2444 2445 int 2446 fget_write(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) 2447 { 2448 2449 return (_fget(td, fd, fpp, FWRITE, rights, NULL)); 2450 } 2451 2452 /* 2453 * Like fget() but loads the underlying vnode, or returns an error if the 2454 * descriptor does not represent a vnode. Note that pipes use vnodes but 2455 * never have VM objects. The returned vnode will be vref()'d. 2456 * 2457 * XXX: what about the unused flags ? 2458 */ 2459 static __inline int 2460 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t needrights, 2461 struct vnode **vpp) 2462 { 2463 struct file *fp; 2464 int error; 2465 2466 *vpp = NULL; 2467 error = _fget(td, fd, &fp, flags, needrights, NULL); 2468 if (error) 2469 return (error); 2470 if (fp->f_vnode == NULL) { 2471 error = EINVAL; 2472 } else { 2473 *vpp = fp->f_vnode; 2474 vref(*vpp); 2475 } 2476 fdrop(fp, td); 2477 2478 return (error); 2479 } 2480 2481 int 2482 fgetvp(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) 2483 { 2484 2485 return (_fgetvp(td, fd, 0, rights, vpp)); 2486 } 2487 2488 int 2489 fgetvp_rights(struct thread *td, int fd, cap_rights_t need, 2490 struct filecaps *havecaps, struct vnode **vpp) 2491 { 2492 struct filedesc *fdp; 2493 struct file *fp; 2494 #ifdef CAPABILITIES 2495 int error; 2496 #endif 2497 2498 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2499 return (EBADF); 2500 2501 fp = fget_locked(fdp, fd); 2502 if (fp == NULL || fp->f_ops == &badfileops) 2503 return (EBADF); 2504 2505 #ifdef CAPABILITIES 2506 error = cap_check(cap_rights(fdp, fd), need); 2507 if (error != 0) 2508 return (error); 2509 #endif 2510 2511 if (fp->f_vnode == NULL) 2512 return (EINVAL); 2513 2514 *vpp = fp->f_vnode; 2515 vref(*vpp); 2516 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2517 2518 return (0); 2519 } 2520 2521 int 2522 fgetvp_read(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) 2523 { 2524 2525 return (_fgetvp(td, fd, FREAD, rights, vpp)); 2526 } 2527 2528 int 2529 fgetvp_exec(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) 2530 { 2531 2532 return (_fgetvp(td, fd, FEXEC, rights, vpp)); 2533 } 2534 2535 #ifdef notyet 2536 int 2537 fgetvp_write(struct thread *td, int fd, cap_rights_t rights, 2538 struct vnode **vpp) 2539 { 2540 2541 return (_fgetvp(td, fd, FWRITE, rights, vpp)); 2542 } 2543 #endif 2544 2545 /* 2546 * Like fget() but loads the underlying socket, or returns an error if the 2547 * descriptor does not represent a socket. 2548 * 2549 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2550 * in the future. 2551 * 2552 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2553 * on their file descriptor reference to prevent the socket from being free'd 2554 * during use. 2555 */ 2556 int 2557 fgetsock(struct thread *td, int fd, cap_rights_t rights, struct socket **spp, 2558 u_int *fflagp) 2559 { 2560 struct file *fp; 2561 int error; 2562 2563 *spp = NULL; 2564 if (fflagp != NULL) 2565 *fflagp = 0; 2566 if ((error = _fget(td, fd, &fp, 0, rights, NULL)) != 0) 2567 return (error); 2568 if (fp->f_type != DTYPE_SOCKET) { 2569 error = ENOTSOCK; 2570 } else { 2571 *spp = fp->f_data; 2572 if (fflagp) 2573 *fflagp = fp->f_flag; 2574 SOCK_LOCK(*spp); 2575 soref(*spp); 2576 SOCK_UNLOCK(*spp); 2577 } 2578 fdrop(fp, td); 2579 2580 return (error); 2581 } 2582 2583 /* 2584 * Drop the reference count on the socket and XXX release the SX lock in the 2585 * future. The last reference closes the socket. 2586 * 2587 * Note: fputsock() is deprecated, see comment for fgetsock(). 2588 */ 2589 void 2590 fputsock(struct socket *so) 2591 { 2592 2593 ACCEPT_LOCK(); 2594 SOCK_LOCK(so); 2595 CURVNET_SET(so->so_vnet); 2596 sorele(so); 2597 CURVNET_RESTORE(); 2598 } 2599 2600 /* 2601 * Handle the last reference to a file being closed. 2602 */ 2603 int 2604 _fdrop(struct file *fp, struct thread *td) 2605 { 2606 int error; 2607 2608 error = 0; 2609 if (fp->f_count != 0) 2610 panic("fdrop: count %d", fp->f_count); 2611 if (fp->f_ops != &badfileops) 2612 error = fo_close(fp, td); 2613 atomic_subtract_int(&openfiles, 1); 2614 crfree(fp->f_cred); 2615 free(fp->f_advice, M_FADVISE); 2616 uma_zfree(file_zone, fp); 2617 2618 return (error); 2619 } 2620 2621 /* 2622 * Apply an advisory lock on a file descriptor. 2623 * 2624 * Just attempt to get a record lock of the requested type on the entire file 2625 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2626 */ 2627 #ifndef _SYS_SYSPROTO_H_ 2628 struct flock_args { 2629 int fd; 2630 int how; 2631 }; 2632 #endif 2633 /* ARGSUSED */ 2634 int 2635 sys_flock(struct thread *td, struct flock_args *uap) 2636 { 2637 struct file *fp; 2638 struct vnode *vp; 2639 struct flock lf; 2640 int error; 2641 2642 if ((error = fget(td, uap->fd, CAP_FLOCK, &fp)) != 0) 2643 return (error); 2644 if (fp->f_type != DTYPE_VNODE) { 2645 fdrop(fp, td); 2646 return (EOPNOTSUPP); 2647 } 2648 2649 vp = fp->f_vnode; 2650 lf.l_whence = SEEK_SET; 2651 lf.l_start = 0; 2652 lf.l_len = 0; 2653 if (uap->how & LOCK_UN) { 2654 lf.l_type = F_UNLCK; 2655 atomic_clear_int(&fp->f_flag, FHASLOCK); 2656 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2657 goto done2; 2658 } 2659 if (uap->how & LOCK_EX) 2660 lf.l_type = F_WRLCK; 2661 else if (uap->how & LOCK_SH) 2662 lf.l_type = F_RDLCK; 2663 else { 2664 error = EBADF; 2665 goto done2; 2666 } 2667 atomic_set_int(&fp->f_flag, FHASLOCK); 2668 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2669 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2670 done2: 2671 fdrop(fp, td); 2672 return (error); 2673 } 2674 /* 2675 * Duplicate the specified descriptor to a free descriptor. 2676 */ 2677 int 2678 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2679 int openerror, int *indxp) 2680 { 2681 struct file *fp; 2682 int error, indx; 2683 2684 KASSERT(openerror == ENODEV || openerror == ENXIO, 2685 ("unexpected error %d in %s", openerror, __func__)); 2686 2687 /* 2688 * If the to-be-dup'd fd number is greater than the allowed number 2689 * of file descriptors, or the fd to be dup'd has already been 2690 * closed, then reject. 2691 */ 2692 FILEDESC_XLOCK(fdp); 2693 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2694 FILEDESC_XUNLOCK(fdp); 2695 return (EBADF); 2696 } 2697 2698 error = fdalloc(td, 0, &indx); 2699 if (error != 0) { 2700 FILEDESC_XUNLOCK(fdp); 2701 return (error); 2702 } 2703 2704 /* 2705 * There are two cases of interest here. 2706 * 2707 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2708 * 2709 * For ENXIO steal away the file structure from (dfd) and store it in 2710 * (indx). (dfd) is effectively closed by this operation. 2711 */ 2712 switch (openerror) { 2713 case ENODEV: 2714 /* 2715 * Check that the mode the file is being opened for is a 2716 * subset of the mode of the existing descriptor. 2717 */ 2718 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2719 fdunused(fdp, indx); 2720 FILEDESC_XUNLOCK(fdp); 2721 return (EACCES); 2722 } 2723 fhold(fp); 2724 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2725 filecaps_copy(&fdp->fd_ofiles[dfd].fde_caps, 2726 &fdp->fd_ofiles[indx].fde_caps); 2727 break; 2728 case ENXIO: 2729 /* 2730 * Steal away the file pointer from dfd and stuff it into indx. 2731 */ 2732 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2733 bzero(&fdp->fd_ofiles[dfd], sizeof(fdp->fd_ofiles[dfd])); 2734 fdunused(fdp, dfd); 2735 break; 2736 } 2737 FILEDESC_XUNLOCK(fdp); 2738 *indxp = indx; 2739 return (0); 2740 } 2741 2742 /* 2743 * Scan all active processes and prisons to see if any of them have a current 2744 * or root directory of `olddp'. If so, replace them with the new mount point. 2745 */ 2746 void 2747 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2748 { 2749 struct filedesc *fdp; 2750 struct prison *pr; 2751 struct proc *p; 2752 int nrele; 2753 2754 if (vrefcnt(olddp) == 1) 2755 return; 2756 nrele = 0; 2757 sx_slock(&allproc_lock); 2758 FOREACH_PROC_IN_SYSTEM(p) { 2759 fdp = fdhold(p); 2760 if (fdp == NULL) 2761 continue; 2762 FILEDESC_XLOCK(fdp); 2763 if (fdp->fd_cdir == olddp) { 2764 vref(newdp); 2765 fdp->fd_cdir = newdp; 2766 nrele++; 2767 } 2768 if (fdp->fd_rdir == olddp) { 2769 vref(newdp); 2770 fdp->fd_rdir = newdp; 2771 nrele++; 2772 } 2773 if (fdp->fd_jdir == olddp) { 2774 vref(newdp); 2775 fdp->fd_jdir = newdp; 2776 nrele++; 2777 } 2778 FILEDESC_XUNLOCK(fdp); 2779 fddrop(fdp); 2780 } 2781 sx_sunlock(&allproc_lock); 2782 if (rootvnode == olddp) { 2783 vref(newdp); 2784 rootvnode = newdp; 2785 nrele++; 2786 } 2787 mtx_lock(&prison0.pr_mtx); 2788 if (prison0.pr_root == olddp) { 2789 vref(newdp); 2790 prison0.pr_root = newdp; 2791 nrele++; 2792 } 2793 mtx_unlock(&prison0.pr_mtx); 2794 sx_slock(&allprison_lock); 2795 TAILQ_FOREACH(pr, &allprison, pr_list) { 2796 mtx_lock(&pr->pr_mtx); 2797 if (pr->pr_root == olddp) { 2798 vref(newdp); 2799 pr->pr_root = newdp; 2800 nrele++; 2801 } 2802 mtx_unlock(&pr->pr_mtx); 2803 } 2804 sx_sunlock(&allprison_lock); 2805 while (nrele--) 2806 vrele(olddp); 2807 } 2808 2809 struct filedesc_to_leader * 2810 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2811 { 2812 struct filedesc_to_leader *fdtol; 2813 2814 fdtol = malloc(sizeof(struct filedesc_to_leader), 2815 M_FILEDESC_TO_LEADER, 2816 M_WAITOK); 2817 fdtol->fdl_refcount = 1; 2818 fdtol->fdl_holdcount = 0; 2819 fdtol->fdl_wakeup = 0; 2820 fdtol->fdl_leader = leader; 2821 if (old != NULL) { 2822 FILEDESC_XLOCK(fdp); 2823 fdtol->fdl_next = old->fdl_next; 2824 fdtol->fdl_prev = old; 2825 old->fdl_next = fdtol; 2826 fdtol->fdl_next->fdl_prev = fdtol; 2827 FILEDESC_XUNLOCK(fdp); 2828 } else { 2829 fdtol->fdl_next = fdtol; 2830 fdtol->fdl_prev = fdtol; 2831 } 2832 return (fdtol); 2833 } 2834 2835 /* 2836 * Get file structures globally. 2837 */ 2838 static int 2839 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2840 { 2841 struct xfile xf; 2842 struct filedesc *fdp; 2843 struct file *fp; 2844 struct proc *p; 2845 int error, n; 2846 2847 error = sysctl_wire_old_buffer(req, 0); 2848 if (error != 0) 2849 return (error); 2850 if (req->oldptr == NULL) { 2851 n = 0; 2852 sx_slock(&allproc_lock); 2853 FOREACH_PROC_IN_SYSTEM(p) { 2854 if (p->p_state == PRS_NEW) 2855 continue; 2856 fdp = fdhold(p); 2857 if (fdp == NULL) 2858 continue; 2859 /* overestimates sparse tables. */ 2860 if (fdp->fd_lastfile > 0) 2861 n += fdp->fd_lastfile; 2862 fddrop(fdp); 2863 } 2864 sx_sunlock(&allproc_lock); 2865 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2866 } 2867 error = 0; 2868 bzero(&xf, sizeof(xf)); 2869 xf.xf_size = sizeof(xf); 2870 sx_slock(&allproc_lock); 2871 FOREACH_PROC_IN_SYSTEM(p) { 2872 PROC_LOCK(p); 2873 if (p->p_state == PRS_NEW) { 2874 PROC_UNLOCK(p); 2875 continue; 2876 } 2877 if (p_cansee(req->td, p) != 0) { 2878 PROC_UNLOCK(p); 2879 continue; 2880 } 2881 xf.xf_pid = p->p_pid; 2882 xf.xf_uid = p->p_ucred->cr_uid; 2883 PROC_UNLOCK(p); 2884 fdp = fdhold(p); 2885 if (fdp == NULL) 2886 continue; 2887 FILEDESC_SLOCK(fdp); 2888 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) { 2889 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 2890 continue; 2891 xf.xf_fd = n; 2892 xf.xf_file = fp; 2893 xf.xf_data = fp->f_data; 2894 xf.xf_vnode = fp->f_vnode; 2895 xf.xf_type = fp->f_type; 2896 xf.xf_count = fp->f_count; 2897 xf.xf_msgcount = 0; 2898 xf.xf_offset = foffset_get(fp); 2899 xf.xf_flag = fp->f_flag; 2900 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2901 if (error) 2902 break; 2903 } 2904 FILEDESC_SUNLOCK(fdp); 2905 fddrop(fdp); 2906 if (error) 2907 break; 2908 } 2909 sx_sunlock(&allproc_lock); 2910 return (error); 2911 } 2912 2913 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD, 2914 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2915 2916 #ifdef KINFO_OFILE_SIZE 2917 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 2918 #endif 2919 2920 #ifdef COMPAT_FREEBSD7 2921 static int 2922 export_vnode_for_osysctl(struct vnode *vp, int type, 2923 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 2924 { 2925 int error; 2926 char *fullpath, *freepath; 2927 2928 bzero(kif, sizeof(*kif)); 2929 kif->kf_structsize = sizeof(*kif); 2930 2931 vref(vp); 2932 kif->kf_fd = type; 2933 kif->kf_type = KF_TYPE_VNODE; 2934 /* This function only handles directories. */ 2935 if (vp->v_type != VDIR) { 2936 vrele(vp); 2937 return (ENOTDIR); 2938 } 2939 kif->kf_vnode_type = KF_VTYPE_VDIR; 2940 2941 /* 2942 * This is not a true file descriptor, so we set a bogus refcount 2943 * and offset to indicate these fields should be ignored. 2944 */ 2945 kif->kf_ref_count = -1; 2946 kif->kf_offset = -1; 2947 2948 freepath = NULL; 2949 fullpath = "-"; 2950 FILEDESC_SUNLOCK(fdp); 2951 vn_fullpath(curthread, vp, &fullpath, &freepath); 2952 vrele(vp); 2953 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 2954 if (freepath != NULL) 2955 free(freepath, M_TEMP); 2956 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 2957 FILEDESC_SLOCK(fdp); 2958 return (error); 2959 } 2960 2961 /* 2962 * Get per-process file descriptors for use by procstat(1), et al. 2963 */ 2964 static int 2965 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 2966 { 2967 char *fullpath, *freepath; 2968 struct kinfo_ofile *kif; 2969 struct filedesc *fdp; 2970 int error, i, *name; 2971 struct shmfd *shmfd; 2972 struct socket *so; 2973 struct vnode *vp; 2974 struct ksem *ks; 2975 struct file *fp; 2976 struct proc *p; 2977 struct tty *tp; 2978 2979 name = (int *)arg1; 2980 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 2981 if (error != 0) 2982 return (error); 2983 fdp = fdhold(p); 2984 PROC_UNLOCK(p); 2985 if (fdp == NULL) 2986 return (ENOENT); 2987 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 2988 FILEDESC_SLOCK(fdp); 2989 if (fdp->fd_cdir != NULL) 2990 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 2991 fdp, req); 2992 if (fdp->fd_rdir != NULL) 2993 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 2994 fdp, req); 2995 if (fdp->fd_jdir != NULL) 2996 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 2997 fdp, req); 2998 for (i = 0; i < fdp->fd_nfiles; i++) { 2999 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3000 continue; 3001 bzero(kif, sizeof(*kif)); 3002 kif->kf_structsize = sizeof(*kif); 3003 ks = NULL; 3004 vp = NULL; 3005 so = NULL; 3006 tp = NULL; 3007 shmfd = NULL; 3008 kif->kf_fd = i; 3009 3010 switch (fp->f_type) { 3011 case DTYPE_VNODE: 3012 kif->kf_type = KF_TYPE_VNODE; 3013 vp = fp->f_vnode; 3014 break; 3015 3016 case DTYPE_SOCKET: 3017 kif->kf_type = KF_TYPE_SOCKET; 3018 so = fp->f_data; 3019 break; 3020 3021 case DTYPE_PIPE: 3022 kif->kf_type = KF_TYPE_PIPE; 3023 break; 3024 3025 case DTYPE_FIFO: 3026 kif->kf_type = KF_TYPE_FIFO; 3027 vp = fp->f_vnode; 3028 break; 3029 3030 case DTYPE_KQUEUE: 3031 kif->kf_type = KF_TYPE_KQUEUE; 3032 break; 3033 3034 case DTYPE_CRYPTO: 3035 kif->kf_type = KF_TYPE_CRYPTO; 3036 break; 3037 3038 case DTYPE_MQUEUE: 3039 kif->kf_type = KF_TYPE_MQUEUE; 3040 break; 3041 3042 case DTYPE_SHM: 3043 kif->kf_type = KF_TYPE_SHM; 3044 shmfd = fp->f_data; 3045 break; 3046 3047 case DTYPE_SEM: 3048 kif->kf_type = KF_TYPE_SEM; 3049 ks = fp->f_data; 3050 break; 3051 3052 case DTYPE_PTS: 3053 kif->kf_type = KF_TYPE_PTS; 3054 tp = fp->f_data; 3055 break; 3056 3057 #ifdef PROCDESC 3058 case DTYPE_PROCDESC: 3059 kif->kf_type = KF_TYPE_PROCDESC; 3060 break; 3061 #endif 3062 3063 default: 3064 kif->kf_type = KF_TYPE_UNKNOWN; 3065 break; 3066 } 3067 kif->kf_ref_count = fp->f_count; 3068 if (fp->f_flag & FREAD) 3069 kif->kf_flags |= KF_FLAG_READ; 3070 if (fp->f_flag & FWRITE) 3071 kif->kf_flags |= KF_FLAG_WRITE; 3072 if (fp->f_flag & FAPPEND) 3073 kif->kf_flags |= KF_FLAG_APPEND; 3074 if (fp->f_flag & FASYNC) 3075 kif->kf_flags |= KF_FLAG_ASYNC; 3076 if (fp->f_flag & FFSYNC) 3077 kif->kf_flags |= KF_FLAG_FSYNC; 3078 if (fp->f_flag & FNONBLOCK) 3079 kif->kf_flags |= KF_FLAG_NONBLOCK; 3080 if (fp->f_flag & O_DIRECT) 3081 kif->kf_flags |= KF_FLAG_DIRECT; 3082 if (fp->f_flag & FHASLOCK) 3083 kif->kf_flags |= KF_FLAG_HASLOCK; 3084 kif->kf_offset = foffset_get(fp); 3085 if (vp != NULL) { 3086 vref(vp); 3087 switch (vp->v_type) { 3088 case VNON: 3089 kif->kf_vnode_type = KF_VTYPE_VNON; 3090 break; 3091 case VREG: 3092 kif->kf_vnode_type = KF_VTYPE_VREG; 3093 break; 3094 case VDIR: 3095 kif->kf_vnode_type = KF_VTYPE_VDIR; 3096 break; 3097 case VBLK: 3098 kif->kf_vnode_type = KF_VTYPE_VBLK; 3099 break; 3100 case VCHR: 3101 kif->kf_vnode_type = KF_VTYPE_VCHR; 3102 break; 3103 case VLNK: 3104 kif->kf_vnode_type = KF_VTYPE_VLNK; 3105 break; 3106 case VSOCK: 3107 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3108 break; 3109 case VFIFO: 3110 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3111 break; 3112 case VBAD: 3113 kif->kf_vnode_type = KF_VTYPE_VBAD; 3114 break; 3115 default: 3116 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3117 break; 3118 } 3119 /* 3120 * It is OK to drop the filedesc lock here as we will 3121 * re-validate and re-evaluate its properties when 3122 * the loop continues. 3123 */ 3124 freepath = NULL; 3125 fullpath = "-"; 3126 FILEDESC_SUNLOCK(fdp); 3127 vn_fullpath(curthread, vp, &fullpath, &freepath); 3128 vrele(vp); 3129 strlcpy(kif->kf_path, fullpath, 3130 sizeof(kif->kf_path)); 3131 if (freepath != NULL) 3132 free(freepath, M_TEMP); 3133 FILEDESC_SLOCK(fdp); 3134 } 3135 if (so != NULL) { 3136 struct sockaddr *sa; 3137 3138 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3139 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3140 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3141 free(sa, M_SONAME); 3142 } 3143 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3144 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3145 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3146 free(sa, M_SONAME); 3147 } 3148 kif->kf_sock_domain = 3149 so->so_proto->pr_domain->dom_family; 3150 kif->kf_sock_type = so->so_type; 3151 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3152 } 3153 if (tp != NULL) { 3154 strlcpy(kif->kf_path, tty_devname(tp), 3155 sizeof(kif->kf_path)); 3156 } 3157 if (shmfd != NULL) 3158 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3159 if (ks != NULL && ksem_info != NULL) 3160 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL); 3161 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3162 if (error) 3163 break; 3164 } 3165 FILEDESC_SUNLOCK(fdp); 3166 fddrop(fdp); 3167 free(kif, M_TEMP); 3168 return (0); 3169 } 3170 3171 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD, 3172 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries"); 3173 #endif /* COMPAT_FREEBSD7 */ 3174 3175 #ifdef KINFO_FILE_SIZE 3176 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3177 #endif 3178 3179 struct export_fd_buf { 3180 struct filedesc *fdp; 3181 struct sbuf *sb; 3182 ssize_t remainder; 3183 struct kinfo_file kif; 3184 }; 3185 3186 static int 3187 export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt, 3188 int64_t offset, cap_rights_t fd_cap_rights, struct export_fd_buf *efbuf) 3189 { 3190 struct { 3191 int fflag; 3192 int kf_fflag; 3193 } fflags_table[] = { 3194 { FAPPEND, KF_FLAG_APPEND }, 3195 { FASYNC, KF_FLAG_ASYNC }, 3196 { FFSYNC, KF_FLAG_FSYNC }, 3197 { FHASLOCK, KF_FLAG_HASLOCK }, 3198 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3199 { FREAD, KF_FLAG_READ }, 3200 { FWRITE, KF_FLAG_WRITE }, 3201 { O_CREAT, KF_FLAG_CREAT }, 3202 { O_DIRECT, KF_FLAG_DIRECT }, 3203 { O_EXCL, KF_FLAG_EXCL }, 3204 { O_EXEC, KF_FLAG_EXEC }, 3205 { O_EXLOCK, KF_FLAG_EXLOCK }, 3206 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3207 { O_SHLOCK, KF_FLAG_SHLOCK }, 3208 { O_TRUNC, KF_FLAG_TRUNC } 3209 }; 3210 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3211 struct kinfo_file *kif; 3212 struct vnode *vp; 3213 int error, locked; 3214 unsigned int i; 3215 3216 if (efbuf->remainder == 0) 3217 return (0); 3218 kif = &efbuf->kif; 3219 bzero(kif, sizeof(*kif)); 3220 locked = efbuf->fdp != NULL; 3221 switch (type) { 3222 case KF_TYPE_FIFO: 3223 case KF_TYPE_VNODE: 3224 if (locked) { 3225 FILEDESC_SUNLOCK(efbuf->fdp); 3226 locked = 0; 3227 } 3228 vp = (struct vnode *)data; 3229 error = fill_vnode_info(vp, kif); 3230 vrele(vp); 3231 break; 3232 case KF_TYPE_SOCKET: 3233 error = fill_socket_info((struct socket *)data, kif); 3234 break; 3235 case KF_TYPE_PIPE: 3236 error = fill_pipe_info((struct pipe *)data, kif); 3237 break; 3238 case KF_TYPE_PTS: 3239 error = fill_pts_info((struct tty *)data, kif); 3240 break; 3241 case KF_TYPE_PROCDESC: 3242 error = fill_procdesc_info((struct procdesc *)data, kif); 3243 break; 3244 case KF_TYPE_SEM: 3245 error = fill_sem_info((struct file *)data, kif); 3246 break; 3247 case KF_TYPE_SHM: 3248 error = fill_shm_info((struct file *)data, kif); 3249 break; 3250 default: 3251 error = 0; 3252 } 3253 if (error == 0) 3254 kif->kf_status |= KF_ATTR_VALID; 3255 3256 /* 3257 * Translate file access flags. 3258 */ 3259 for (i = 0; i < NFFLAGS; i++) 3260 if (fflags & fflags_table[i].fflag) 3261 kif->kf_flags |= fflags_table[i].kf_fflag; 3262 kif->kf_cap_rights = fd_cap_rights; 3263 kif->kf_fd = fd; 3264 kif->kf_type = type; 3265 kif->kf_ref_count = refcnt; 3266 kif->kf_offset = offset; 3267 /* Pack record size down */ 3268 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3269 strlen(kif->kf_path) + 1; 3270 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3271 if (efbuf->remainder != -1) { 3272 if (efbuf->remainder < kif->kf_structsize) { 3273 /* Terminate export. */ 3274 efbuf->remainder = 0; 3275 if (efbuf->fdp != NULL && !locked) 3276 FILEDESC_SLOCK(efbuf->fdp); 3277 return (0); 3278 } 3279 efbuf->remainder -= kif->kf_structsize; 3280 } 3281 if (locked) 3282 FILEDESC_SUNLOCK(efbuf->fdp); 3283 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize); 3284 if (efbuf->fdp != NULL) 3285 FILEDESC_SLOCK(efbuf->fdp); 3286 return (error); 3287 } 3288 3289 /* 3290 * Store a process file descriptor information to sbuf. 3291 * 3292 * Takes a locked proc as argument, and returns with the proc unlocked. 3293 */ 3294 int 3295 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3296 { 3297 struct file *fp; 3298 struct filedesc *fdp; 3299 struct export_fd_buf *efbuf; 3300 struct vnode *cttyvp, *textvp, *tracevp; 3301 int64_t offset; 3302 void *data; 3303 int error, i; 3304 int type, refcnt, fflags; 3305 cap_rights_t fd_cap_rights; 3306 3307 PROC_LOCK_ASSERT(p, MA_OWNED); 3308 3309 /* ktrace vnode */ 3310 tracevp = p->p_tracevp; 3311 if (tracevp != NULL) 3312 vref(tracevp); 3313 /* text vnode */ 3314 textvp = p->p_textvp; 3315 if (textvp != NULL) 3316 vref(textvp); 3317 /* Controlling tty. */ 3318 cttyvp = NULL; 3319 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3320 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3321 if (cttyvp != NULL) 3322 vref(cttyvp); 3323 } 3324 fdp = fdhold(p); 3325 PROC_UNLOCK(p); 3326 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3327 efbuf->fdp = NULL; 3328 efbuf->sb = sb; 3329 efbuf->remainder = maxlen; 3330 if (tracevp != NULL) 3331 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3332 FREAD | FWRITE, -1, -1, 0, efbuf); 3333 if (textvp != NULL) 3334 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3335 FREAD, -1, -1, 0, efbuf); 3336 if (cttyvp != NULL) 3337 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3338 FREAD | FWRITE, -1, -1, 0, efbuf); 3339 error = 0; 3340 if (fdp == NULL) 3341 goto fail; 3342 efbuf->fdp = fdp; 3343 FILEDESC_SLOCK(fdp); 3344 /* working directory */ 3345 if (fdp->fd_cdir != NULL) { 3346 vref(fdp->fd_cdir); 3347 data = fdp->fd_cdir; 3348 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3349 FREAD, -1, -1, 0, efbuf); 3350 } 3351 /* root directory */ 3352 if (fdp->fd_rdir != NULL) { 3353 vref(fdp->fd_rdir); 3354 data = fdp->fd_rdir; 3355 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3356 FREAD, -1, -1, 0, efbuf); 3357 } 3358 /* jail directory */ 3359 if (fdp->fd_jdir != NULL) { 3360 vref(fdp->fd_jdir); 3361 data = fdp->fd_jdir; 3362 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3363 FREAD, -1, -1, 0, efbuf); 3364 } 3365 for (i = 0; i < fdp->fd_nfiles; i++) { 3366 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3367 continue; 3368 data = NULL; 3369 #ifdef CAPABILITIES 3370 fd_cap_rights = cap_rights(fdp, i); 3371 #else /* !CAPABILITIES */ 3372 fd_cap_rights = 0; 3373 #endif 3374 switch (fp->f_type) { 3375 case DTYPE_VNODE: 3376 type = KF_TYPE_VNODE; 3377 vref(fp->f_vnode); 3378 data = fp->f_vnode; 3379 break; 3380 3381 case DTYPE_SOCKET: 3382 type = KF_TYPE_SOCKET; 3383 data = fp->f_data; 3384 break; 3385 3386 case DTYPE_PIPE: 3387 type = KF_TYPE_PIPE; 3388 data = fp->f_data; 3389 break; 3390 3391 case DTYPE_FIFO: 3392 type = KF_TYPE_FIFO; 3393 vref(fp->f_vnode); 3394 data = fp->f_vnode; 3395 break; 3396 3397 case DTYPE_KQUEUE: 3398 type = KF_TYPE_KQUEUE; 3399 break; 3400 3401 case DTYPE_CRYPTO: 3402 type = KF_TYPE_CRYPTO; 3403 break; 3404 3405 case DTYPE_MQUEUE: 3406 type = KF_TYPE_MQUEUE; 3407 break; 3408 3409 case DTYPE_SHM: 3410 type = KF_TYPE_SHM; 3411 data = fp; 3412 break; 3413 3414 case DTYPE_SEM: 3415 type = KF_TYPE_SEM; 3416 data = fp; 3417 break; 3418 3419 case DTYPE_PTS: 3420 type = KF_TYPE_PTS; 3421 data = fp->f_data; 3422 break; 3423 3424 #ifdef PROCDESC 3425 case DTYPE_PROCDESC: 3426 type = KF_TYPE_PROCDESC; 3427 data = fp->f_data; 3428 break; 3429 #endif 3430 3431 default: 3432 type = KF_TYPE_UNKNOWN; 3433 break; 3434 } 3435 refcnt = fp->f_count; 3436 fflags = fp->f_flag; 3437 offset = foffset_get(fp); 3438 3439 /* 3440 * Create sysctl entry. 3441 * It is OK to drop the filedesc lock here as we will 3442 * re-validate and re-evaluate its properties when 3443 * the loop continues. 3444 */ 3445 error = export_fd_to_sb(data, type, i, fflags, refcnt, 3446 offset, fd_cap_rights, efbuf); 3447 if (error) 3448 break; 3449 } 3450 FILEDESC_SUNLOCK(fdp); 3451 fddrop(fdp); 3452 fail: 3453 free(efbuf, M_TEMP); 3454 return (error); 3455 } 3456 3457 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3458 3459 /* 3460 * Get per-process file descriptors for use by procstat(1), et al. 3461 */ 3462 static int 3463 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3464 { 3465 struct sbuf sb; 3466 struct proc *p; 3467 ssize_t maxlen; 3468 int error, error2, *name; 3469 3470 name = (int *)arg1; 3471 3472 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3473 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3474 if (error != 0) { 3475 sbuf_delete(&sb); 3476 return (error); 3477 } 3478 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3479 error = kern_proc_filedesc_out(p, &sb, maxlen); 3480 error2 = sbuf_finish(&sb); 3481 sbuf_delete(&sb); 3482 return (error != 0 ? error : error2); 3483 } 3484 3485 int 3486 vntype_to_kinfo(int vtype) 3487 { 3488 struct { 3489 int vtype; 3490 int kf_vtype; 3491 } vtypes_table[] = { 3492 { VBAD, KF_VTYPE_VBAD }, 3493 { VBLK, KF_VTYPE_VBLK }, 3494 { VCHR, KF_VTYPE_VCHR }, 3495 { VDIR, KF_VTYPE_VDIR }, 3496 { VFIFO, KF_VTYPE_VFIFO }, 3497 { VLNK, KF_VTYPE_VLNK }, 3498 { VNON, KF_VTYPE_VNON }, 3499 { VREG, KF_VTYPE_VREG }, 3500 { VSOCK, KF_VTYPE_VSOCK } 3501 }; 3502 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3503 unsigned int i; 3504 3505 /* 3506 * Perform vtype translation. 3507 */ 3508 for (i = 0; i < NVTYPES; i++) 3509 if (vtypes_table[i].vtype == vtype) 3510 break; 3511 if (i < NVTYPES) 3512 return (vtypes_table[i].kf_vtype); 3513 3514 return (KF_VTYPE_UNKNOWN); 3515 } 3516 3517 static int 3518 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3519 { 3520 struct vattr va; 3521 char *fullpath, *freepath; 3522 int error; 3523 3524 if (vp == NULL) 3525 return (1); 3526 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3527 freepath = NULL; 3528 fullpath = "-"; 3529 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3530 if (error == 0) { 3531 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3532 } 3533 if (freepath != NULL) 3534 free(freepath, M_TEMP); 3535 3536 /* 3537 * Retrieve vnode attributes. 3538 */ 3539 va.va_fsid = VNOVAL; 3540 va.va_rdev = NODEV; 3541 vn_lock(vp, LK_SHARED | LK_RETRY); 3542 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3543 VOP_UNLOCK(vp, 0); 3544 if (error != 0) 3545 return (error); 3546 if (va.va_fsid != VNOVAL) 3547 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3548 else 3549 kif->kf_un.kf_file.kf_file_fsid = 3550 vp->v_mount->mnt_stat.f_fsid.val[0]; 3551 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3552 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3553 kif->kf_un.kf_file.kf_file_size = va.va_size; 3554 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3555 return (0); 3556 } 3557 3558 static int 3559 fill_socket_info(struct socket *so, struct kinfo_file *kif) 3560 { 3561 struct sockaddr *sa; 3562 struct inpcb *inpcb; 3563 struct unpcb *unpcb; 3564 int error; 3565 3566 if (so == NULL) 3567 return (1); 3568 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3569 kif->kf_sock_type = so->so_type; 3570 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3571 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3572 switch(kif->kf_sock_domain) { 3573 case AF_INET: 3574 case AF_INET6: 3575 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3576 if (so->so_pcb != NULL) { 3577 inpcb = (struct inpcb *)(so->so_pcb); 3578 kif->kf_un.kf_sock.kf_sock_inpcb = 3579 (uintptr_t)inpcb->inp_ppcb; 3580 } 3581 } 3582 break; 3583 case AF_UNIX: 3584 if (so->so_pcb != NULL) { 3585 unpcb = (struct unpcb *)(so->so_pcb); 3586 if (unpcb->unp_conn) { 3587 kif->kf_un.kf_sock.kf_sock_unpconn = 3588 (uintptr_t)unpcb->unp_conn; 3589 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3590 so->so_rcv.sb_state; 3591 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3592 so->so_snd.sb_state; 3593 } 3594 } 3595 break; 3596 } 3597 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3598 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3599 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3600 free(sa, M_SONAME); 3601 } 3602 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3603 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3604 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3605 free(sa, M_SONAME); 3606 } 3607 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3608 sizeof(kif->kf_path)); 3609 return (0); 3610 } 3611 3612 static int 3613 fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3614 { 3615 3616 if (tp == NULL) 3617 return (1); 3618 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3619 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3620 return (0); 3621 } 3622 3623 static int 3624 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3625 { 3626 3627 if (pi == NULL) 3628 return (1); 3629 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3630 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3631 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3632 return (0); 3633 } 3634 3635 static int 3636 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3637 { 3638 3639 if (pdp == NULL) 3640 return (1); 3641 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3642 return (0); 3643 } 3644 3645 static int 3646 fill_sem_info(struct file *fp, struct kinfo_file *kif) 3647 { 3648 struct thread *td; 3649 struct stat sb; 3650 3651 td = curthread; 3652 if (fp->f_data == NULL) 3653 return (1); 3654 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3655 return (1); 3656 if (ksem_info == NULL) 3657 return (1); 3658 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path), 3659 &kif->kf_un.kf_sem.kf_sem_value); 3660 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode; 3661 return (0); 3662 } 3663 3664 static int 3665 fill_shm_info(struct file *fp, struct kinfo_file *kif) 3666 { 3667 struct thread *td; 3668 struct stat sb; 3669 3670 td = curthread; 3671 if (fp->f_data == NULL) 3672 return (1); 3673 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3674 return (1); 3675 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3676 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3677 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3678 return (0); 3679 } 3680 3681 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD, 3682 sysctl_kern_proc_filedesc, "Process filedesc entries"); 3683 3684 #ifdef DDB 3685 /* 3686 * For the purposes of debugging, generate a human-readable string for the 3687 * file type. 3688 */ 3689 static const char * 3690 file_type_to_name(short type) 3691 { 3692 3693 switch (type) { 3694 case 0: 3695 return ("zero"); 3696 case DTYPE_VNODE: 3697 return ("vnod"); 3698 case DTYPE_SOCKET: 3699 return ("sock"); 3700 case DTYPE_PIPE: 3701 return ("pipe"); 3702 case DTYPE_FIFO: 3703 return ("fifo"); 3704 case DTYPE_KQUEUE: 3705 return ("kque"); 3706 case DTYPE_CRYPTO: 3707 return ("crpt"); 3708 case DTYPE_MQUEUE: 3709 return ("mque"); 3710 case DTYPE_SHM: 3711 return ("shm"); 3712 case DTYPE_SEM: 3713 return ("ksem"); 3714 default: 3715 return ("unkn"); 3716 } 3717 } 3718 3719 /* 3720 * For the purposes of debugging, identify a process (if any, perhaps one of 3721 * many) that references the passed file in its file descriptor array. Return 3722 * NULL if none. 3723 */ 3724 static struct proc * 3725 file_to_first_proc(struct file *fp) 3726 { 3727 struct filedesc *fdp; 3728 struct proc *p; 3729 int n; 3730 3731 FOREACH_PROC_IN_SYSTEM(p) { 3732 if (p->p_state == PRS_NEW) 3733 continue; 3734 fdp = p->p_fd; 3735 if (fdp == NULL) 3736 continue; 3737 for (n = 0; n < fdp->fd_nfiles; n++) { 3738 if (fp == fdp->fd_ofiles[n].fde_file) 3739 return (p); 3740 } 3741 } 3742 return (NULL); 3743 } 3744 3745 static void 3746 db_print_file(struct file *fp, int header) 3747 { 3748 struct proc *p; 3749 3750 if (header) 3751 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3752 "File", "Type", "Data", "Flag", "GCFl", "Count", 3753 "MCount", "Vnode", "FPID", "FCmd"); 3754 p = file_to_first_proc(fp); 3755 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3756 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3757 0, fp->f_count, 0, fp->f_vnode, 3758 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3759 } 3760 3761 DB_SHOW_COMMAND(file, db_show_file) 3762 { 3763 struct file *fp; 3764 3765 if (!have_addr) { 3766 db_printf("usage: show file <addr>\n"); 3767 return; 3768 } 3769 fp = (struct file *)addr; 3770 db_print_file(fp, 1); 3771 } 3772 3773 DB_SHOW_COMMAND(files, db_show_files) 3774 { 3775 struct filedesc *fdp; 3776 struct file *fp; 3777 struct proc *p; 3778 int header; 3779 int n; 3780 3781 header = 1; 3782 FOREACH_PROC_IN_SYSTEM(p) { 3783 if (p->p_state == PRS_NEW) 3784 continue; 3785 if ((fdp = p->p_fd) == NULL) 3786 continue; 3787 for (n = 0; n < fdp->fd_nfiles; ++n) { 3788 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3789 continue; 3790 db_print_file(fp, header); 3791 header = 0; 3792 } 3793 } 3794 } 3795 #endif 3796 3797 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3798 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3799 3800 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3801 &maxfiles, 0, "Maximum number of files"); 3802 3803 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3804 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3805 3806 /* ARGSUSED*/ 3807 static void 3808 filelistinit(void *dummy) 3809 { 3810 3811 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3812 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3813 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3814 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3815 } 3816 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3817 3818 /*-------------------------------------------------------------------*/ 3819 3820 static int 3821 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3822 int flags, struct thread *td) 3823 { 3824 3825 return (EBADF); 3826 } 3827 3828 static int 3829 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3830 struct thread *td) 3831 { 3832 3833 return (EINVAL); 3834 } 3835 3836 static int 3837 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3838 struct thread *td) 3839 { 3840 3841 return (EBADF); 3842 } 3843 3844 static int 3845 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3846 struct thread *td) 3847 { 3848 3849 return (0); 3850 } 3851 3852 static int 3853 badfo_kqfilter(struct file *fp, struct knote *kn) 3854 { 3855 3856 return (EBADF); 3857 } 3858 3859 static int 3860 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3861 struct thread *td) 3862 { 3863 3864 return (EBADF); 3865 } 3866 3867 static int 3868 badfo_close(struct file *fp, struct thread *td) 3869 { 3870 3871 return (EBADF); 3872 } 3873 3874 static int 3875 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3876 struct thread *td) 3877 { 3878 3879 return (EBADF); 3880 } 3881 3882 static int 3883 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3884 struct thread *td) 3885 { 3886 3887 return (EBADF); 3888 } 3889 3890 static int 3891 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3892 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3893 int kflags, struct thread *td) 3894 { 3895 3896 return (EBADF); 3897 } 3898 3899 struct fileops badfileops = { 3900 .fo_read = badfo_readwrite, 3901 .fo_write = badfo_readwrite, 3902 .fo_truncate = badfo_truncate, 3903 .fo_ioctl = badfo_ioctl, 3904 .fo_poll = badfo_poll, 3905 .fo_kqfilter = badfo_kqfilter, 3906 .fo_stat = badfo_stat, 3907 .fo_close = badfo_close, 3908 .fo_chmod = badfo_chmod, 3909 .fo_chown = badfo_chown, 3910 .fo_sendfile = badfo_sendfile, 3911 }; 3912 3913 int 3914 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3915 struct thread *td) 3916 { 3917 3918 return (EINVAL); 3919 } 3920 3921 int 3922 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3923 struct thread *td) 3924 { 3925 3926 return (EINVAL); 3927 } 3928 3929 int 3930 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3931 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3932 int kflags, struct thread *td) 3933 { 3934 3935 return (EINVAL); 3936 } 3937 3938 /*-------------------------------------------------------------------*/ 3939 3940 /* 3941 * File Descriptor pseudo-device driver (/dev/fd/). 3942 * 3943 * Opening minor device N dup()s the file (if any) connected to file 3944 * descriptor N belonging to the calling process. Note that this driver 3945 * consists of only the ``open()'' routine, because all subsequent 3946 * references to this file will be direct to the other driver. 3947 * 3948 * XXX: we could give this one a cloning event handler if necessary. 3949 */ 3950 3951 /* ARGSUSED */ 3952 static int 3953 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 3954 { 3955 3956 /* 3957 * XXX Kludge: set curthread->td_dupfd to contain the value of the 3958 * the file descriptor being sought for duplication. The error 3959 * return ensures that the vnode for this device will be released 3960 * by vn_open. Open will detect this special error and take the 3961 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 3962 * will simply report the error. 3963 */ 3964 td->td_dupfd = dev2unit(dev); 3965 return (ENODEV); 3966 } 3967 3968 static struct cdevsw fildesc_cdevsw = { 3969 .d_version = D_VERSION, 3970 .d_open = fdopen, 3971 .d_name = "FD", 3972 }; 3973 3974 static void 3975 fildesc_drvinit(void *unused) 3976 { 3977 struct cdev *dev; 3978 3979 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 3980 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 3981 make_dev_alias(dev, "stdin"); 3982 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 3983 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 3984 make_dev_alias(dev, "stdout"); 3985 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 3986 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 3987 make_dev_alias(dev, "stderr"); 3988 } 3989 3990 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 3991