1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1989, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include "opt_capsicum.h" 43 #include "opt_ddb.h" 44 #include "opt_ktrace.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 49 #include <sys/capsicum.h> 50 #include <sys/conf.h> 51 #include <sys/fcntl.h> 52 #include <sys/file.h> 53 #include <sys/filedesc.h> 54 #include <sys/filio.h> 55 #include <sys/jail.h> 56 #include <sys/kernel.h> 57 #include <sys/limits.h> 58 #include <sys/lock.h> 59 #include <sys/malloc.h> 60 #include <sys/mount.h> 61 #include <sys/mutex.h> 62 #include <sys/namei.h> 63 #include <sys/selinfo.h> 64 #include <sys/priv.h> 65 #include <sys/proc.h> 66 #include <sys/protosw.h> 67 #include <sys/racct.h> 68 #include <sys/resourcevar.h> 69 #include <sys/sbuf.h> 70 #include <sys/signalvar.h> 71 #include <sys/kdb.h> 72 #include <sys/stat.h> 73 #include <sys/sx.h> 74 #include <sys/syscallsubr.h> 75 #include <sys/sysctl.h> 76 #include <sys/sysproto.h> 77 #include <sys/unistd.h> 78 #include <sys/user.h> 79 #include <sys/vnode.h> 80 #ifdef KTRACE 81 #include <sys/ktrace.h> 82 #endif 83 84 #include <net/vnet.h> 85 86 #include <security/audit/audit.h> 87 88 #include <vm/uma.h> 89 #include <vm/vm.h> 90 91 #include <ddb/ddb.h> 92 93 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 94 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 95 "file desc to leader structures"); 96 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 97 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 98 99 MALLOC_DECLARE(M_FADVISE); 100 101 static __read_mostly uma_zone_t file_zone; 102 static __read_mostly uma_zone_t filedesc0_zone; 103 104 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 105 struct thread *td, int holdleaders); 106 static int fd_first_free(struct filedesc *fdp, int low, int size); 107 static int fd_last_used(struct filedesc *fdp, int size); 108 static void fdgrowtable(struct filedesc *fdp, int nfd); 109 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 110 static void fdunused(struct filedesc *fdp, int fd); 111 static void fdused(struct filedesc *fdp, int fd); 112 static int getmaxfd(struct thread *td); 113 static u_long *filecaps_copy_prep(const struct filecaps *src); 114 static void filecaps_copy_finish(const struct filecaps *src, 115 struct filecaps *dst, u_long *ioctls); 116 static u_long *filecaps_free_prep(struct filecaps *fcaps); 117 static void filecaps_free_finish(u_long *ioctls); 118 119 /* 120 * Each process has: 121 * 122 * - An array of open file descriptors (fd_ofiles) 123 * - An array of file flags (fd_ofileflags) 124 * - A bitmap recording which descriptors are in use (fd_map) 125 * 126 * A process starts out with NDFILE descriptors. The value of NDFILE has 127 * been selected based the historical limit of 20 open files, and an 128 * assumption that the majority of processes, especially short-lived 129 * processes like shells, will never need more. 130 * 131 * If this initial allocation is exhausted, a larger descriptor table and 132 * map are allocated dynamically, and the pointers in the process's struct 133 * filedesc are updated to point to those. This is repeated every time 134 * the process runs out of file descriptors (provided it hasn't hit its 135 * resource limit). 136 * 137 * Since threads may hold references to individual descriptor table 138 * entries, the tables are never freed. Instead, they are placed on a 139 * linked list and freed only when the struct filedesc is released. 140 */ 141 #define NDFILE 20 142 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 143 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 144 #define NDSLOT(x) ((x) / NDENTRIES) 145 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 146 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 147 148 /* 149 * SLIST entry used to keep track of ofiles which must be reclaimed when 150 * the process exits. 151 */ 152 struct freetable { 153 struct fdescenttbl *ft_table; 154 SLIST_ENTRY(freetable) ft_next; 155 }; 156 157 /* 158 * Initial allocation: a filedesc structure + the head of SLIST used to 159 * keep track of old ofiles + enough space for NDFILE descriptors. 160 */ 161 162 struct fdescenttbl0 { 163 int fdt_nfiles; 164 struct filedescent fdt_ofiles[NDFILE]; 165 }; 166 167 struct filedesc0 { 168 struct filedesc fd_fd; 169 SLIST_HEAD(, freetable) fd_free; 170 struct fdescenttbl0 fd_dfiles; 171 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 172 }; 173 174 /* 175 * Descriptor management. 176 */ 177 static int __exclusive_cache_line openfiles; /* actual number of open files */ 178 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 179 void __read_mostly (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 180 181 /* 182 * If low >= size, just return low. Otherwise find the first zero bit in the 183 * given bitmap, starting at low and not exceeding size - 1. Return size if 184 * not found. 185 */ 186 static int 187 fd_first_free(struct filedesc *fdp, int low, int size) 188 { 189 NDSLOTTYPE *map = fdp->fd_map; 190 NDSLOTTYPE mask; 191 int off, maxoff; 192 193 if (low >= size) 194 return (low); 195 196 off = NDSLOT(low); 197 if (low % NDENTRIES) { 198 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 199 if ((mask &= ~map[off]) != 0UL) 200 return (off * NDENTRIES + ffsl(mask) - 1); 201 ++off; 202 } 203 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 204 if (map[off] != ~0UL) 205 return (off * NDENTRIES + ffsl(~map[off]) - 1); 206 return (size); 207 } 208 209 /* 210 * Find the highest non-zero bit in the given bitmap, starting at 0 and 211 * not exceeding size - 1. Return -1 if not found. 212 */ 213 static int 214 fd_last_used(struct filedesc *fdp, int size) 215 { 216 NDSLOTTYPE *map = fdp->fd_map; 217 NDSLOTTYPE mask; 218 int off, minoff; 219 220 off = NDSLOT(size); 221 if (size % NDENTRIES) { 222 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 223 if ((mask &= map[off]) != 0) 224 return (off * NDENTRIES + flsl(mask) - 1); 225 --off; 226 } 227 for (minoff = NDSLOT(0); off >= minoff; --off) 228 if (map[off] != 0) 229 return (off * NDENTRIES + flsl(map[off]) - 1); 230 return (-1); 231 } 232 233 static int 234 fdisused(struct filedesc *fdp, int fd) 235 { 236 237 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 238 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 239 240 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 241 } 242 243 /* 244 * Mark a file descriptor as used. 245 */ 246 static void 247 fdused_init(struct filedesc *fdp, int fd) 248 { 249 250 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 251 252 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 253 } 254 255 static void 256 fdused(struct filedesc *fdp, int fd) 257 { 258 259 FILEDESC_XLOCK_ASSERT(fdp); 260 261 fdused_init(fdp, fd); 262 if (fd > fdp->fd_lastfile) 263 fdp->fd_lastfile = fd; 264 if (fd == fdp->fd_freefile) 265 fdp->fd_freefile++; 266 } 267 268 /* 269 * Mark a file descriptor as unused. 270 */ 271 static void 272 fdunused(struct filedesc *fdp, int fd) 273 { 274 275 FILEDESC_XLOCK_ASSERT(fdp); 276 277 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 278 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 279 ("fd=%d is still in use", fd)); 280 281 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 282 if (fd < fdp->fd_freefile) 283 fdp->fd_freefile = fd; 284 if (fd == fdp->fd_lastfile) 285 fdp->fd_lastfile = fd_last_used(fdp, fd); 286 } 287 288 /* 289 * Free a file descriptor. 290 * 291 * Avoid some work if fdp is about to be destroyed. 292 */ 293 static inline void 294 fdefree_last(struct filedescent *fde) 295 { 296 297 filecaps_free(&fde->fde_caps); 298 } 299 300 static inline void 301 fdfree(struct filedesc *fdp, int fd) 302 { 303 struct filedescent *fde; 304 305 fde = &fdp->fd_ofiles[fd]; 306 #ifdef CAPABILITIES 307 seqc_write_begin(&fde->fde_seqc); 308 #endif 309 fde->fde_file = NULL; 310 #ifdef CAPABILITIES 311 seqc_write_end(&fde->fde_seqc); 312 #endif 313 fdefree_last(fde); 314 fdunused(fdp, fd); 315 } 316 317 void 318 pwd_ensure_dirs(void) 319 { 320 struct filedesc *fdp; 321 322 fdp = curproc->p_fd; 323 FILEDESC_XLOCK(fdp); 324 if (fdp->fd_cdir == NULL) { 325 fdp->fd_cdir = rootvnode; 326 vrefact(rootvnode); 327 } 328 if (fdp->fd_rdir == NULL) { 329 fdp->fd_rdir = rootvnode; 330 vrefact(rootvnode); 331 } 332 FILEDESC_XUNLOCK(fdp); 333 } 334 335 /* 336 * System calls on descriptors. 337 */ 338 #ifndef _SYS_SYSPROTO_H_ 339 struct getdtablesize_args { 340 int dummy; 341 }; 342 #endif 343 /* ARGSUSED */ 344 int 345 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 346 { 347 #ifdef RACCT 348 uint64_t lim; 349 #endif 350 351 td->td_retval[0] = getmaxfd(td); 352 #ifdef RACCT 353 PROC_LOCK(td->td_proc); 354 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 355 PROC_UNLOCK(td->td_proc); 356 if (lim < td->td_retval[0]) 357 td->td_retval[0] = lim; 358 #endif 359 return (0); 360 } 361 362 /* 363 * Duplicate a file descriptor to a particular value. 364 * 365 * Note: keep in mind that a potential race condition exists when closing 366 * descriptors from a shared descriptor table (via rfork). 367 */ 368 #ifndef _SYS_SYSPROTO_H_ 369 struct dup2_args { 370 u_int from; 371 u_int to; 372 }; 373 #endif 374 /* ARGSUSED */ 375 int 376 sys_dup2(struct thread *td, struct dup2_args *uap) 377 { 378 379 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to)); 380 } 381 382 /* 383 * Duplicate a file descriptor. 384 */ 385 #ifndef _SYS_SYSPROTO_H_ 386 struct dup_args { 387 u_int fd; 388 }; 389 #endif 390 /* ARGSUSED */ 391 int 392 sys_dup(struct thread *td, struct dup_args *uap) 393 { 394 395 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0)); 396 } 397 398 /* 399 * The file control system call. 400 */ 401 #ifndef _SYS_SYSPROTO_H_ 402 struct fcntl_args { 403 int fd; 404 int cmd; 405 long arg; 406 }; 407 #endif 408 /* ARGSUSED */ 409 int 410 sys_fcntl(struct thread *td, struct fcntl_args *uap) 411 { 412 413 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg)); 414 } 415 416 int 417 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg) 418 { 419 struct flock fl; 420 struct __oflock ofl; 421 intptr_t arg1; 422 int error, newcmd; 423 424 error = 0; 425 newcmd = cmd; 426 switch (cmd) { 427 case F_OGETLK: 428 case F_OSETLK: 429 case F_OSETLKW: 430 /* 431 * Convert old flock structure to new. 432 */ 433 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl)); 434 fl.l_start = ofl.l_start; 435 fl.l_len = ofl.l_len; 436 fl.l_pid = ofl.l_pid; 437 fl.l_type = ofl.l_type; 438 fl.l_whence = ofl.l_whence; 439 fl.l_sysid = 0; 440 441 switch (cmd) { 442 case F_OGETLK: 443 newcmd = F_GETLK; 444 break; 445 case F_OSETLK: 446 newcmd = F_SETLK; 447 break; 448 case F_OSETLKW: 449 newcmd = F_SETLKW; 450 break; 451 } 452 arg1 = (intptr_t)&fl; 453 break; 454 case F_GETLK: 455 case F_SETLK: 456 case F_SETLKW: 457 case F_SETLK_REMOTE: 458 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl)); 459 arg1 = (intptr_t)&fl; 460 break; 461 default: 462 arg1 = arg; 463 break; 464 } 465 if (error) 466 return (error); 467 error = kern_fcntl(td, fd, newcmd, arg1); 468 if (error) 469 return (error); 470 if (cmd == F_OGETLK) { 471 ofl.l_start = fl.l_start; 472 ofl.l_len = fl.l_len; 473 ofl.l_pid = fl.l_pid; 474 ofl.l_type = fl.l_type; 475 ofl.l_whence = fl.l_whence; 476 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl)); 477 } else if (cmd == F_GETLK) { 478 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl)); 479 } 480 return (error); 481 } 482 483 int 484 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 485 { 486 struct filedesc *fdp; 487 struct flock *flp; 488 struct file *fp, *fp2; 489 struct filedescent *fde; 490 struct proc *p; 491 struct vnode *vp; 492 struct mount *mp; 493 int error, flg, seals, tmp; 494 uint64_t bsize; 495 off_t foffset; 496 497 error = 0; 498 flg = F_POSIX; 499 p = td->td_proc; 500 fdp = p->p_fd; 501 502 AUDIT_ARG_FD(cmd); 503 AUDIT_ARG_CMD(cmd); 504 switch (cmd) { 505 case F_DUPFD: 506 tmp = arg; 507 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp); 508 break; 509 510 case F_DUPFD_CLOEXEC: 511 tmp = arg; 512 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp); 513 break; 514 515 case F_DUP2FD: 516 tmp = arg; 517 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp); 518 break; 519 520 case F_DUP2FD_CLOEXEC: 521 tmp = arg; 522 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp); 523 break; 524 525 case F_GETFD: 526 error = EBADF; 527 FILEDESC_SLOCK(fdp); 528 fde = fdeget_locked(fdp, fd); 529 if (fde != NULL) { 530 td->td_retval[0] = 531 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 532 error = 0; 533 } 534 FILEDESC_SUNLOCK(fdp); 535 break; 536 537 case F_SETFD: 538 error = EBADF; 539 FILEDESC_XLOCK(fdp); 540 fde = fdeget_locked(fdp, fd); 541 if (fde != NULL) { 542 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 543 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 544 error = 0; 545 } 546 FILEDESC_XUNLOCK(fdp); 547 break; 548 549 case F_GETFL: 550 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETFL, &fp); 551 if (error != 0) 552 break; 553 td->td_retval[0] = OFLAGS(fp->f_flag); 554 fdrop(fp, td); 555 break; 556 557 case F_SETFL: 558 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETFL, &fp); 559 if (error != 0) 560 break; 561 do { 562 tmp = flg = fp->f_flag; 563 tmp &= ~FCNTLFLAGS; 564 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 565 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 566 tmp = fp->f_flag & FNONBLOCK; 567 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 568 if (error != 0) { 569 fdrop(fp, td); 570 break; 571 } 572 tmp = fp->f_flag & FASYNC; 573 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 574 if (error == 0) { 575 fdrop(fp, td); 576 break; 577 } 578 atomic_clear_int(&fp->f_flag, FNONBLOCK); 579 tmp = 0; 580 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 581 fdrop(fp, td); 582 break; 583 584 case F_GETOWN: 585 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETOWN, &fp); 586 if (error != 0) 587 break; 588 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 589 if (error == 0) 590 td->td_retval[0] = tmp; 591 fdrop(fp, td); 592 break; 593 594 case F_SETOWN: 595 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETOWN, &fp); 596 if (error != 0) 597 break; 598 tmp = arg; 599 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 600 fdrop(fp, td); 601 break; 602 603 case F_SETLK_REMOTE: 604 error = priv_check(td, PRIV_NFS_LOCKD); 605 if (error != 0) 606 return (error); 607 flg = F_REMOTE; 608 goto do_setlk; 609 610 case F_SETLKW: 611 flg |= F_WAIT; 612 /* FALLTHROUGH F_SETLK */ 613 614 case F_SETLK: 615 do_setlk: 616 flp = (struct flock *)arg; 617 if ((flg & F_REMOTE) != 0 && flp->l_sysid == 0) { 618 error = EINVAL; 619 break; 620 } 621 622 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp, NULL); 623 if (error != 0) 624 break; 625 if (fp->f_type != DTYPE_VNODE) { 626 error = EBADF; 627 fdrop(fp, td); 628 break; 629 } 630 631 if (flp->l_whence == SEEK_CUR) { 632 foffset = foffset_get(fp); 633 if (foffset < 0 || 634 (flp->l_start > 0 && 635 foffset > OFF_MAX - flp->l_start)) { 636 error = EOVERFLOW; 637 fdrop(fp, td); 638 break; 639 } 640 flp->l_start += foffset; 641 } 642 643 vp = fp->f_vnode; 644 switch (flp->l_type) { 645 case F_RDLCK: 646 if ((fp->f_flag & FREAD) == 0) { 647 error = EBADF; 648 break; 649 } 650 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { 651 PROC_LOCK(p->p_leader); 652 p->p_leader->p_flag |= P_ADVLOCK; 653 PROC_UNLOCK(p->p_leader); 654 } 655 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 656 flp, flg); 657 break; 658 case F_WRLCK: 659 if ((fp->f_flag & FWRITE) == 0) { 660 error = EBADF; 661 break; 662 } 663 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { 664 PROC_LOCK(p->p_leader); 665 p->p_leader->p_flag |= P_ADVLOCK; 666 PROC_UNLOCK(p->p_leader); 667 } 668 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 669 flp, flg); 670 break; 671 case F_UNLCK: 672 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 673 flp, flg); 674 break; 675 case F_UNLCKSYS: 676 if (flg != F_REMOTE) { 677 error = EINVAL; 678 break; 679 } 680 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 681 F_UNLCKSYS, flp, flg); 682 break; 683 default: 684 error = EINVAL; 685 break; 686 } 687 if (error != 0 || flp->l_type == F_UNLCK || 688 flp->l_type == F_UNLCKSYS) { 689 fdrop(fp, td); 690 break; 691 } 692 693 /* 694 * Check for a race with close. 695 * 696 * The vnode is now advisory locked (or unlocked, but this case 697 * is not really important) as the caller requested. 698 * We had to drop the filedesc lock, so we need to recheck if 699 * the descriptor is still valid, because if it was closed 700 * in the meantime we need to remove advisory lock from the 701 * vnode - close on any descriptor leading to an advisory 702 * locked vnode, removes that lock. 703 * We will return 0 on purpose in that case, as the result of 704 * successful advisory lock might have been externally visible 705 * already. This is fine - effectively we pretend to the caller 706 * that the closing thread was a bit slower and that the 707 * advisory lock succeeded before the close. 708 */ 709 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp2, NULL); 710 if (error != 0) { 711 fdrop(fp, td); 712 break; 713 } 714 if (fp != fp2) { 715 flp->l_whence = SEEK_SET; 716 flp->l_start = 0; 717 flp->l_len = 0; 718 flp->l_type = F_UNLCK; 719 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 720 F_UNLCK, flp, F_POSIX); 721 } 722 fdrop(fp, td); 723 fdrop(fp2, td); 724 break; 725 726 case F_GETLK: 727 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp, NULL); 728 if (error != 0) 729 break; 730 if (fp->f_type != DTYPE_VNODE) { 731 error = EBADF; 732 fdrop(fp, td); 733 break; 734 } 735 flp = (struct flock *)arg; 736 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 737 flp->l_type != F_UNLCK) { 738 error = EINVAL; 739 fdrop(fp, td); 740 break; 741 } 742 if (flp->l_whence == SEEK_CUR) { 743 foffset = foffset_get(fp); 744 if ((flp->l_start > 0 && 745 foffset > OFF_MAX - flp->l_start) || 746 (flp->l_start < 0 && 747 foffset < OFF_MIN - flp->l_start)) { 748 error = EOVERFLOW; 749 fdrop(fp, td); 750 break; 751 } 752 flp->l_start += foffset; 753 } 754 vp = fp->f_vnode; 755 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 756 F_POSIX); 757 fdrop(fp, td); 758 break; 759 760 case F_ADD_SEALS: 761 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp, NULL); 762 if (error != 0) 763 break; 764 error = fo_add_seals(fp, arg); 765 fdrop(fp, td); 766 break; 767 768 case F_GET_SEALS: 769 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp, NULL); 770 if (error != 0) 771 break; 772 if (fo_get_seals(fp, &seals) == 0) 773 td->td_retval[0] = seals; 774 else 775 error = EINVAL; 776 fdrop(fp, td); 777 break; 778 779 case F_RDAHEAD: 780 arg = arg ? 128 * 1024: 0; 781 /* FALLTHROUGH */ 782 case F_READAHEAD: 783 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp, NULL); 784 if (error != 0) 785 break; 786 if (fp->f_type != DTYPE_VNODE) { 787 fdrop(fp, td); 788 error = EBADF; 789 break; 790 } 791 vp = fp->f_vnode; 792 if (vp->v_type != VREG) { 793 fdrop(fp, td); 794 error = ENOTTY; 795 break; 796 } 797 798 /* 799 * Exclusive lock synchronizes against f_seqcount reads and 800 * writes in sequential_heuristic(). 801 */ 802 error = vn_lock(vp, LK_EXCLUSIVE); 803 if (error != 0) { 804 fdrop(fp, td); 805 break; 806 } 807 if (arg >= 0) { 808 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 809 arg = MIN(arg, INT_MAX - bsize + 1); 810 fp->f_seqcount = MIN(IO_SEQMAX, 811 (arg + bsize - 1) / bsize); 812 atomic_set_int(&fp->f_flag, FRDAHEAD); 813 } else { 814 atomic_clear_int(&fp->f_flag, FRDAHEAD); 815 } 816 VOP_UNLOCK(vp); 817 fdrop(fp, td); 818 break; 819 820 case F_ISUNIONSTACK: 821 /* 822 * Check if the vnode is part of a union stack (either the 823 * "union" flag from mount(2) or unionfs). 824 * 825 * Prior to introduction of this op libc's readdir would call 826 * fstatfs(2), in effect unnecessarily copying kilobytes of 827 * data just to check fs name and a mount flag. 828 * 829 * Fixing the code to handle everything in the kernel instead 830 * is a non-trivial endeavor and has low priority, thus this 831 * horrible kludge facilitates the current behavior in a much 832 * cheaper manner until someone(tm) sorts this out. 833 */ 834 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp, NULL); 835 if (error != 0) 836 break; 837 if (fp->f_type != DTYPE_VNODE) { 838 fdrop(fp, td); 839 error = EBADF; 840 break; 841 } 842 vp = fp->f_vnode; 843 /* 844 * Since we don't prevent dooming the vnode even non-null mp 845 * found can become immediately stale. This is tolerable since 846 * mount points are type-stable (providing safe memory access) 847 * and any vfs op on this vnode going forward will return an 848 * error (meaning return value in this case is meaningless). 849 */ 850 mp = (struct mount *)atomic_load_ptr(&vp->v_mount); 851 if (__predict_false(mp == NULL)) { 852 fdrop(fp, td); 853 error = EBADF; 854 break; 855 } 856 td->td_retval[0] = 0; 857 if (mp->mnt_kern_flag & MNTK_UNIONFS || 858 mp->mnt_flag & MNT_UNION) 859 td->td_retval[0] = 1; 860 fdrop(fp, td); 861 break; 862 863 default: 864 error = EINVAL; 865 break; 866 } 867 return (error); 868 } 869 870 static int 871 getmaxfd(struct thread *td) 872 { 873 874 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc)); 875 } 876 877 /* 878 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 879 */ 880 int 881 kern_dup(struct thread *td, u_int mode, int flags, int old, int new) 882 { 883 struct filedesc *fdp; 884 struct filedescent *oldfde, *newfde; 885 struct proc *p; 886 struct file *delfp; 887 u_long *oioctls, *nioctls; 888 int error, maxfd; 889 890 p = td->td_proc; 891 fdp = p->p_fd; 892 oioctls = NULL; 893 894 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0); 895 MPASS(mode < FDDUP_LASTMODE); 896 897 AUDIT_ARG_FD(old); 898 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */ 899 900 /* 901 * Verify we have a valid descriptor to dup from and possibly to 902 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 903 * return EINVAL when the new descriptor is out of bounds. 904 */ 905 if (old < 0) 906 return (EBADF); 907 if (new < 0) 908 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 909 maxfd = getmaxfd(td); 910 if (new >= maxfd) 911 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 912 913 error = EBADF; 914 FILEDESC_XLOCK(fdp); 915 if (fget_locked(fdp, old) == NULL) 916 goto unlock; 917 if ((mode == FDDUP_FIXED || mode == FDDUP_MUSTREPLACE) && old == new) { 918 td->td_retval[0] = new; 919 if (flags & FDDUP_FLAG_CLOEXEC) 920 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 921 error = 0; 922 goto unlock; 923 } 924 925 oldfde = &fdp->fd_ofiles[old]; 926 if (!fhold(oldfde->fde_file)) 927 goto unlock; 928 929 /* 930 * If the caller specified a file descriptor, make sure the file 931 * table is large enough to hold it, and grab it. Otherwise, just 932 * allocate a new descriptor the usual way. 933 */ 934 switch (mode) { 935 case FDDUP_NORMAL: 936 case FDDUP_FCNTL: 937 if ((error = fdalloc(td, new, &new)) != 0) { 938 fdrop(oldfde->fde_file, td); 939 goto unlock; 940 } 941 break; 942 case FDDUP_MUSTREPLACE: 943 /* Target file descriptor must exist. */ 944 if (fget_locked(fdp, new) == NULL) { 945 fdrop(oldfde->fde_file, td); 946 goto unlock; 947 } 948 break; 949 case FDDUP_FIXED: 950 if (new >= fdp->fd_nfiles) { 951 /* 952 * The resource limits are here instead of e.g. 953 * fdalloc(), because the file descriptor table may be 954 * shared between processes, so we can't really use 955 * racct_add()/racct_sub(). Instead of counting the 956 * number of actually allocated descriptors, just put 957 * the limit on the size of the file descriptor table. 958 */ 959 #ifdef RACCT 960 if (RACCT_ENABLED()) { 961 error = racct_set_unlocked(p, RACCT_NOFILE, new + 1); 962 if (error != 0) { 963 error = EMFILE; 964 fdrop(oldfde->fde_file, td); 965 goto unlock; 966 } 967 } 968 #endif 969 fdgrowtable_exp(fdp, new + 1); 970 } 971 if (!fdisused(fdp, new)) 972 fdused(fdp, new); 973 break; 974 default: 975 KASSERT(0, ("%s unsupported mode %d", __func__, mode)); 976 } 977 978 KASSERT(old != new, ("new fd is same as old")); 979 980 newfde = &fdp->fd_ofiles[new]; 981 delfp = newfde->fde_file; 982 983 oioctls = filecaps_free_prep(&newfde->fde_caps); 984 nioctls = filecaps_copy_prep(&oldfde->fde_caps); 985 986 /* 987 * Duplicate the source descriptor. 988 */ 989 #ifdef CAPABILITIES 990 seqc_write_begin(&newfde->fde_seqc); 991 #endif 992 memcpy(newfde, oldfde, fde_change_size); 993 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps, 994 nioctls); 995 if ((flags & FDDUP_FLAG_CLOEXEC) != 0) 996 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 997 else 998 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 999 #ifdef CAPABILITIES 1000 seqc_write_end(&newfde->fde_seqc); 1001 #endif 1002 td->td_retval[0] = new; 1003 1004 error = 0; 1005 1006 if (delfp != NULL) { 1007 (void) closefp(fdp, new, delfp, td, 1); 1008 FILEDESC_UNLOCK_ASSERT(fdp); 1009 } else { 1010 unlock: 1011 FILEDESC_XUNLOCK(fdp); 1012 } 1013 1014 filecaps_free_finish(oioctls); 1015 return (error); 1016 } 1017 1018 /* 1019 * If sigio is on the list associated with a process or process group, 1020 * disable signalling from the device, remove sigio from the list and 1021 * free sigio. 1022 */ 1023 void 1024 funsetown(struct sigio **sigiop) 1025 { 1026 struct sigio *sigio; 1027 1028 if (*sigiop == NULL) 1029 return; 1030 SIGIO_LOCK(); 1031 sigio = *sigiop; 1032 if (sigio == NULL) { 1033 SIGIO_UNLOCK(); 1034 return; 1035 } 1036 *(sigio->sio_myref) = NULL; 1037 if ((sigio)->sio_pgid < 0) { 1038 struct pgrp *pg = (sigio)->sio_pgrp; 1039 PGRP_LOCK(pg); 1040 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 1041 sigio, sio_pgsigio); 1042 PGRP_UNLOCK(pg); 1043 } else { 1044 struct proc *p = (sigio)->sio_proc; 1045 PROC_LOCK(p); 1046 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 1047 sigio, sio_pgsigio); 1048 PROC_UNLOCK(p); 1049 } 1050 SIGIO_UNLOCK(); 1051 crfree(sigio->sio_ucred); 1052 free(sigio, M_SIGIO); 1053 } 1054 1055 /* 1056 * Free a list of sigio structures. 1057 * We only need to lock the SIGIO_LOCK because we have made ourselves 1058 * inaccessible to callers of fsetown and therefore do not need to lock 1059 * the proc or pgrp struct for the list manipulation. 1060 */ 1061 void 1062 funsetownlst(struct sigiolst *sigiolst) 1063 { 1064 struct proc *p; 1065 struct pgrp *pg; 1066 struct sigio *sigio; 1067 1068 sigio = SLIST_FIRST(sigiolst); 1069 if (sigio == NULL) 1070 return; 1071 p = NULL; 1072 pg = NULL; 1073 1074 /* 1075 * Every entry of the list should belong 1076 * to a single proc or pgrp. 1077 */ 1078 if (sigio->sio_pgid < 0) { 1079 pg = sigio->sio_pgrp; 1080 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 1081 } else /* if (sigio->sio_pgid > 0) */ { 1082 p = sigio->sio_proc; 1083 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 1084 } 1085 1086 SIGIO_LOCK(); 1087 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 1088 *(sigio->sio_myref) = NULL; 1089 if (pg != NULL) { 1090 KASSERT(sigio->sio_pgid < 0, 1091 ("Proc sigio in pgrp sigio list")); 1092 KASSERT(sigio->sio_pgrp == pg, 1093 ("Bogus pgrp in sigio list")); 1094 PGRP_LOCK(pg); 1095 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 1096 sio_pgsigio); 1097 PGRP_UNLOCK(pg); 1098 } else /* if (p != NULL) */ { 1099 KASSERT(sigio->sio_pgid > 0, 1100 ("Pgrp sigio in proc sigio list")); 1101 KASSERT(sigio->sio_proc == p, 1102 ("Bogus proc in sigio list")); 1103 PROC_LOCK(p); 1104 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 1105 sio_pgsigio); 1106 PROC_UNLOCK(p); 1107 } 1108 SIGIO_UNLOCK(); 1109 crfree(sigio->sio_ucred); 1110 free(sigio, M_SIGIO); 1111 SIGIO_LOCK(); 1112 } 1113 SIGIO_UNLOCK(); 1114 } 1115 1116 /* 1117 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1118 * 1119 * After permission checking, add a sigio structure to the sigio list for 1120 * the process or process group. 1121 */ 1122 int 1123 fsetown(pid_t pgid, struct sigio **sigiop) 1124 { 1125 struct proc *proc; 1126 struct pgrp *pgrp; 1127 struct sigio *sigio; 1128 int ret; 1129 1130 if (pgid == 0) { 1131 funsetown(sigiop); 1132 return (0); 1133 } 1134 1135 ret = 0; 1136 1137 /* Allocate and fill in the new sigio out of locks. */ 1138 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1139 sigio->sio_pgid = pgid; 1140 sigio->sio_ucred = crhold(curthread->td_ucred); 1141 sigio->sio_myref = sigiop; 1142 1143 sx_slock(&proctree_lock); 1144 if (pgid > 0) { 1145 proc = pfind(pgid); 1146 if (proc == NULL) { 1147 ret = ESRCH; 1148 goto fail; 1149 } 1150 1151 /* 1152 * Policy - Don't allow a process to FSETOWN a process 1153 * in another session. 1154 * 1155 * Remove this test to allow maximum flexibility or 1156 * restrict FSETOWN to the current process or process 1157 * group for maximum safety. 1158 */ 1159 PROC_UNLOCK(proc); 1160 if (proc->p_session != curthread->td_proc->p_session) { 1161 ret = EPERM; 1162 goto fail; 1163 } 1164 1165 pgrp = NULL; 1166 } else /* if (pgid < 0) */ { 1167 pgrp = pgfind(-pgid); 1168 if (pgrp == NULL) { 1169 ret = ESRCH; 1170 goto fail; 1171 } 1172 PGRP_UNLOCK(pgrp); 1173 1174 /* 1175 * Policy - Don't allow a process to FSETOWN a process 1176 * in another session. 1177 * 1178 * Remove this test to allow maximum flexibility or 1179 * restrict FSETOWN to the current process or process 1180 * group for maximum safety. 1181 */ 1182 if (pgrp->pg_session != curthread->td_proc->p_session) { 1183 ret = EPERM; 1184 goto fail; 1185 } 1186 1187 proc = NULL; 1188 } 1189 funsetown(sigiop); 1190 if (pgid > 0) { 1191 PROC_LOCK(proc); 1192 /* 1193 * Since funsetownlst() is called without the proctree 1194 * locked, we need to check for P_WEXIT. 1195 * XXX: is ESRCH correct? 1196 */ 1197 if ((proc->p_flag & P_WEXIT) != 0) { 1198 PROC_UNLOCK(proc); 1199 ret = ESRCH; 1200 goto fail; 1201 } 1202 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1203 sigio->sio_proc = proc; 1204 PROC_UNLOCK(proc); 1205 } else { 1206 PGRP_LOCK(pgrp); 1207 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1208 sigio->sio_pgrp = pgrp; 1209 PGRP_UNLOCK(pgrp); 1210 } 1211 sx_sunlock(&proctree_lock); 1212 SIGIO_LOCK(); 1213 *sigiop = sigio; 1214 SIGIO_UNLOCK(); 1215 return (0); 1216 1217 fail: 1218 sx_sunlock(&proctree_lock); 1219 crfree(sigio->sio_ucred); 1220 free(sigio, M_SIGIO); 1221 return (ret); 1222 } 1223 1224 /* 1225 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1226 */ 1227 pid_t 1228 fgetown(struct sigio **sigiop) 1229 { 1230 pid_t pgid; 1231 1232 SIGIO_LOCK(); 1233 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1234 SIGIO_UNLOCK(); 1235 return (pgid); 1236 } 1237 1238 /* 1239 * Function drops the filedesc lock on return. 1240 */ 1241 static int 1242 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1243 int holdleaders) 1244 { 1245 int error; 1246 1247 FILEDESC_XLOCK_ASSERT(fdp); 1248 1249 if (holdleaders) { 1250 if (td->td_proc->p_fdtol != NULL) { 1251 /* 1252 * Ask fdfree() to sleep to ensure that all relevant 1253 * process leaders can be traversed in closef(). 1254 */ 1255 fdp->fd_holdleaderscount++; 1256 } else { 1257 holdleaders = 0; 1258 } 1259 } 1260 1261 /* 1262 * We now hold the fp reference that used to be owned by the 1263 * descriptor array. We have to unlock the FILEDESC *AFTER* 1264 * knote_fdclose to prevent a race of the fd getting opened, a knote 1265 * added, and deleteing a knote for the new fd. 1266 */ 1267 if (__predict_false(!TAILQ_EMPTY(&fdp->fd_kqlist))) 1268 knote_fdclose(td, fd); 1269 1270 /* 1271 * We need to notify mqueue if the object is of type mqueue. 1272 */ 1273 if (__predict_false(fp->f_type == DTYPE_MQUEUE)) 1274 mq_fdclose(td, fd, fp); 1275 FILEDESC_XUNLOCK(fdp); 1276 1277 error = closef(fp, td); 1278 if (holdleaders) { 1279 FILEDESC_XLOCK(fdp); 1280 fdp->fd_holdleaderscount--; 1281 if (fdp->fd_holdleaderscount == 0 && 1282 fdp->fd_holdleaderswakeup != 0) { 1283 fdp->fd_holdleaderswakeup = 0; 1284 wakeup(&fdp->fd_holdleaderscount); 1285 } 1286 FILEDESC_XUNLOCK(fdp); 1287 } 1288 return (error); 1289 } 1290 1291 /* 1292 * Close a file descriptor. 1293 */ 1294 #ifndef _SYS_SYSPROTO_H_ 1295 struct close_args { 1296 int fd; 1297 }; 1298 #endif 1299 /* ARGSUSED */ 1300 int 1301 sys_close(struct thread *td, struct close_args *uap) 1302 { 1303 1304 return (kern_close(td, uap->fd)); 1305 } 1306 1307 int 1308 kern_close(struct thread *td, int fd) 1309 { 1310 struct filedesc *fdp; 1311 struct file *fp; 1312 1313 fdp = td->td_proc->p_fd; 1314 1315 AUDIT_SYSCLOSE(td, fd); 1316 1317 FILEDESC_XLOCK(fdp); 1318 if ((fp = fget_locked(fdp, fd)) == NULL) { 1319 FILEDESC_XUNLOCK(fdp); 1320 return (EBADF); 1321 } 1322 fdfree(fdp, fd); 1323 1324 /* closefp() drops the FILEDESC lock for us. */ 1325 return (closefp(fdp, fd, fp, td, 1)); 1326 } 1327 1328 /* 1329 * Close open file descriptors. 1330 */ 1331 #ifndef _SYS_SYSPROTO_H_ 1332 struct closefrom_args { 1333 int lowfd; 1334 }; 1335 #endif 1336 /* ARGSUSED */ 1337 int 1338 sys_closefrom(struct thread *td, struct closefrom_args *uap) 1339 { 1340 struct filedesc *fdp; 1341 int fd; 1342 1343 fdp = td->td_proc->p_fd; 1344 AUDIT_ARG_FD(uap->lowfd); 1345 1346 /* 1347 * Treat negative starting file descriptor values identical to 1348 * closefrom(0) which closes all files. 1349 */ 1350 if (uap->lowfd < 0) 1351 uap->lowfd = 0; 1352 FILEDESC_SLOCK(fdp); 1353 for (fd = uap->lowfd; fd <= fdp->fd_lastfile; fd++) { 1354 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1355 FILEDESC_SUNLOCK(fdp); 1356 (void)kern_close(td, fd); 1357 FILEDESC_SLOCK(fdp); 1358 } 1359 } 1360 FILEDESC_SUNLOCK(fdp); 1361 return (0); 1362 } 1363 1364 #if defined(COMPAT_43) 1365 /* 1366 * Return status information about a file descriptor. 1367 */ 1368 #ifndef _SYS_SYSPROTO_H_ 1369 struct ofstat_args { 1370 int fd; 1371 struct ostat *sb; 1372 }; 1373 #endif 1374 /* ARGSUSED */ 1375 int 1376 ofstat(struct thread *td, struct ofstat_args *uap) 1377 { 1378 struct ostat oub; 1379 struct stat ub; 1380 int error; 1381 1382 error = kern_fstat(td, uap->fd, &ub); 1383 if (error == 0) { 1384 cvtstat(&ub, &oub); 1385 error = copyout(&oub, uap->sb, sizeof(oub)); 1386 } 1387 return (error); 1388 } 1389 #endif /* COMPAT_43 */ 1390 1391 #if defined(COMPAT_FREEBSD11) 1392 int 1393 freebsd11_fstat(struct thread *td, struct freebsd11_fstat_args *uap) 1394 { 1395 struct stat sb; 1396 struct freebsd11_stat osb; 1397 int error; 1398 1399 error = kern_fstat(td, uap->fd, &sb); 1400 if (error != 0) 1401 return (error); 1402 error = freebsd11_cvtstat(&sb, &osb); 1403 if (error == 0) 1404 error = copyout(&osb, uap->sb, sizeof(osb)); 1405 return (error); 1406 } 1407 #endif /* COMPAT_FREEBSD11 */ 1408 1409 /* 1410 * Return status information about a file descriptor. 1411 */ 1412 #ifndef _SYS_SYSPROTO_H_ 1413 struct fstat_args { 1414 int fd; 1415 struct stat *sb; 1416 }; 1417 #endif 1418 /* ARGSUSED */ 1419 int 1420 sys_fstat(struct thread *td, struct fstat_args *uap) 1421 { 1422 struct stat ub; 1423 int error; 1424 1425 error = kern_fstat(td, uap->fd, &ub); 1426 if (error == 0) 1427 error = copyout(&ub, uap->sb, sizeof(ub)); 1428 return (error); 1429 } 1430 1431 int 1432 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1433 { 1434 struct file *fp; 1435 int error; 1436 1437 AUDIT_ARG_FD(fd); 1438 1439 error = fget(td, fd, &cap_fstat_rights, &fp); 1440 if (error != 0) 1441 return (error); 1442 1443 AUDIT_ARG_FILE(td->td_proc, fp); 1444 1445 error = fo_stat(fp, sbp, td->td_ucred, td); 1446 fdrop(fp, td); 1447 #ifdef __STAT_TIME_T_EXT 1448 if (error == 0) { 1449 sbp->st_atim_ext = 0; 1450 sbp->st_mtim_ext = 0; 1451 sbp->st_ctim_ext = 0; 1452 sbp->st_btim_ext = 0; 1453 } 1454 #endif 1455 #ifdef KTRACE 1456 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1457 ktrstat(sbp); 1458 #endif 1459 return (error); 1460 } 1461 1462 #if defined(COMPAT_FREEBSD11) 1463 /* 1464 * Return status information about a file descriptor. 1465 */ 1466 #ifndef _SYS_SYSPROTO_H_ 1467 struct freebsd11_nfstat_args { 1468 int fd; 1469 struct nstat *sb; 1470 }; 1471 #endif 1472 /* ARGSUSED */ 1473 int 1474 freebsd11_nfstat(struct thread *td, struct freebsd11_nfstat_args *uap) 1475 { 1476 struct nstat nub; 1477 struct stat ub; 1478 int error; 1479 1480 error = kern_fstat(td, uap->fd, &ub); 1481 if (error == 0) { 1482 freebsd11_cvtnstat(&ub, &nub); 1483 error = copyout(&nub, uap->sb, sizeof(nub)); 1484 } 1485 return (error); 1486 } 1487 #endif /* COMPAT_FREEBSD11 */ 1488 1489 /* 1490 * Return pathconf information about a file descriptor. 1491 */ 1492 #ifndef _SYS_SYSPROTO_H_ 1493 struct fpathconf_args { 1494 int fd; 1495 int name; 1496 }; 1497 #endif 1498 /* ARGSUSED */ 1499 int 1500 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1501 { 1502 long value; 1503 int error; 1504 1505 error = kern_fpathconf(td, uap->fd, uap->name, &value); 1506 if (error == 0) 1507 td->td_retval[0] = value; 1508 return (error); 1509 } 1510 1511 int 1512 kern_fpathconf(struct thread *td, int fd, int name, long *valuep) 1513 { 1514 struct file *fp; 1515 struct vnode *vp; 1516 int error; 1517 1518 error = fget(td, fd, &cap_fpathconf_rights, &fp); 1519 if (error != 0) 1520 return (error); 1521 1522 if (name == _PC_ASYNC_IO) { 1523 *valuep = _POSIX_ASYNCHRONOUS_IO; 1524 goto out; 1525 } 1526 vp = fp->f_vnode; 1527 if (vp != NULL) { 1528 vn_lock(vp, LK_SHARED | LK_RETRY); 1529 error = VOP_PATHCONF(vp, name, valuep); 1530 VOP_UNLOCK(vp); 1531 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1532 if (name != _PC_PIPE_BUF) { 1533 error = EINVAL; 1534 } else { 1535 *valuep = PIPE_BUF; 1536 error = 0; 1537 } 1538 } else { 1539 error = EOPNOTSUPP; 1540 } 1541 out: 1542 fdrop(fp, td); 1543 return (error); 1544 } 1545 1546 /* 1547 * Copy filecaps structure allocating memory for ioctls array if needed. 1548 * 1549 * The last parameter indicates whether the fdtable is locked. If it is not and 1550 * ioctls are encountered, copying fails and the caller must lock the table. 1551 * 1552 * Note that if the table was not locked, the caller has to check the relevant 1553 * sequence counter to determine whether the operation was successful. 1554 */ 1555 bool 1556 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked) 1557 { 1558 size_t size; 1559 1560 if (src->fc_ioctls != NULL && !locked) 1561 return (false); 1562 memcpy(dst, src, sizeof(*src)); 1563 if (src->fc_ioctls == NULL) 1564 return (true); 1565 1566 KASSERT(src->fc_nioctls > 0, 1567 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1568 1569 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1570 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1571 memcpy(dst->fc_ioctls, src->fc_ioctls, size); 1572 return (true); 1573 } 1574 1575 static u_long * 1576 filecaps_copy_prep(const struct filecaps *src) 1577 { 1578 u_long *ioctls; 1579 size_t size; 1580 1581 if (__predict_true(src->fc_ioctls == NULL)) 1582 return (NULL); 1583 1584 KASSERT(src->fc_nioctls > 0, 1585 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1586 1587 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1588 ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1589 return (ioctls); 1590 } 1591 1592 static void 1593 filecaps_copy_finish(const struct filecaps *src, struct filecaps *dst, 1594 u_long *ioctls) 1595 { 1596 size_t size; 1597 1598 *dst = *src; 1599 if (__predict_true(src->fc_ioctls == NULL)) { 1600 MPASS(ioctls == NULL); 1601 return; 1602 } 1603 1604 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1605 dst->fc_ioctls = ioctls; 1606 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1607 } 1608 1609 /* 1610 * Move filecaps structure to the new place and clear the old place. 1611 */ 1612 void 1613 filecaps_move(struct filecaps *src, struct filecaps *dst) 1614 { 1615 1616 *dst = *src; 1617 bzero(src, sizeof(*src)); 1618 } 1619 1620 /* 1621 * Fill the given filecaps structure with full rights. 1622 */ 1623 static void 1624 filecaps_fill(struct filecaps *fcaps) 1625 { 1626 1627 CAP_ALL(&fcaps->fc_rights); 1628 fcaps->fc_ioctls = NULL; 1629 fcaps->fc_nioctls = -1; 1630 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1631 } 1632 1633 /* 1634 * Free memory allocated within filecaps structure. 1635 */ 1636 void 1637 filecaps_free(struct filecaps *fcaps) 1638 { 1639 1640 free(fcaps->fc_ioctls, M_FILECAPS); 1641 bzero(fcaps, sizeof(*fcaps)); 1642 } 1643 1644 static u_long * 1645 filecaps_free_prep(struct filecaps *fcaps) 1646 { 1647 u_long *ioctls; 1648 1649 ioctls = fcaps->fc_ioctls; 1650 bzero(fcaps, sizeof(*fcaps)); 1651 return (ioctls); 1652 } 1653 1654 static void 1655 filecaps_free_finish(u_long *ioctls) 1656 { 1657 1658 free(ioctls, M_FILECAPS); 1659 } 1660 1661 /* 1662 * Validate the given filecaps structure. 1663 */ 1664 static void 1665 filecaps_validate(const struct filecaps *fcaps, const char *func) 1666 { 1667 1668 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1669 ("%s: invalid rights", func)); 1670 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1671 ("%s: invalid fcntls", func)); 1672 KASSERT(fcaps->fc_fcntls == 0 || 1673 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1674 ("%s: fcntls without CAP_FCNTL", func)); 1675 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1676 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1677 ("%s: invalid ioctls", func)); 1678 KASSERT(fcaps->fc_nioctls == 0 || 1679 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1680 ("%s: ioctls without CAP_IOCTL", func)); 1681 } 1682 1683 static void 1684 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1685 { 1686 int nfd1; 1687 1688 FILEDESC_XLOCK_ASSERT(fdp); 1689 1690 nfd1 = fdp->fd_nfiles * 2; 1691 if (nfd1 < nfd) 1692 nfd1 = nfd; 1693 fdgrowtable(fdp, nfd1); 1694 } 1695 1696 /* 1697 * Grow the file table to accommodate (at least) nfd descriptors. 1698 */ 1699 static void 1700 fdgrowtable(struct filedesc *fdp, int nfd) 1701 { 1702 struct filedesc0 *fdp0; 1703 struct freetable *ft; 1704 struct fdescenttbl *ntable; 1705 struct fdescenttbl *otable; 1706 int nnfiles, onfiles; 1707 NDSLOTTYPE *nmap, *omap; 1708 1709 /* 1710 * If lastfile is -1 this struct filedesc was just allocated and we are 1711 * growing it to accommodate for the one we are going to copy from. There 1712 * is no need to have a lock on this one as it's not visible to anyone. 1713 */ 1714 if (fdp->fd_lastfile != -1) 1715 FILEDESC_XLOCK_ASSERT(fdp); 1716 1717 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1718 1719 /* save old values */ 1720 onfiles = fdp->fd_nfiles; 1721 otable = fdp->fd_files; 1722 omap = fdp->fd_map; 1723 1724 /* compute the size of the new table */ 1725 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1726 if (nnfiles <= onfiles) 1727 /* the table is already large enough */ 1728 return; 1729 1730 /* 1731 * Allocate a new table. We need enough space for the number of 1732 * entries, file entries themselves and the struct freetable we will use 1733 * when we decommission the table and place it on the freelist. 1734 * We place the struct freetable in the middle so we don't have 1735 * to worry about padding. 1736 */ 1737 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) + 1738 nnfiles * sizeof(ntable->fdt_ofiles[0]) + 1739 sizeof(struct freetable), 1740 M_FILEDESC, M_ZERO | M_WAITOK); 1741 /* copy the old data */ 1742 ntable->fdt_nfiles = nnfiles; 1743 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles, 1744 onfiles * sizeof(ntable->fdt_ofiles[0])); 1745 1746 /* 1747 * Allocate a new map only if the old is not large enough. It will 1748 * grow at a slower rate than the table as it can map more 1749 * entries than the table can hold. 1750 */ 1751 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1752 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1753 M_ZERO | M_WAITOK); 1754 /* copy over the old data and update the pointer */ 1755 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1756 fdp->fd_map = nmap; 1757 } 1758 1759 /* 1760 * Make sure that ntable is correctly initialized before we replace 1761 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent 1762 * data. 1763 */ 1764 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable); 1765 1766 /* 1767 * Do not free the old file table, as some threads may still 1768 * reference entries within it. Instead, place it on a freelist 1769 * which will be processed when the struct filedesc is released. 1770 * 1771 * Note that if onfiles == NDFILE, we're dealing with the original 1772 * static allocation contained within (struct filedesc0 *)fdp, 1773 * which must not be freed. 1774 */ 1775 if (onfiles > NDFILE) { 1776 ft = (struct freetable *)&otable->fdt_ofiles[onfiles]; 1777 fdp0 = (struct filedesc0 *)fdp; 1778 ft->ft_table = otable; 1779 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1780 } 1781 /* 1782 * The map does not have the same possibility of threads still 1783 * holding references to it. So always free it as long as it 1784 * does not reference the original static allocation. 1785 */ 1786 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1787 free(omap, M_FILEDESC); 1788 } 1789 1790 /* 1791 * Allocate a file descriptor for the process. 1792 */ 1793 int 1794 fdalloc(struct thread *td, int minfd, int *result) 1795 { 1796 struct proc *p = td->td_proc; 1797 struct filedesc *fdp = p->p_fd; 1798 int fd, maxfd, allocfd; 1799 #ifdef RACCT 1800 int error; 1801 #endif 1802 1803 FILEDESC_XLOCK_ASSERT(fdp); 1804 1805 if (fdp->fd_freefile > minfd) 1806 minfd = fdp->fd_freefile; 1807 1808 maxfd = getmaxfd(td); 1809 1810 /* 1811 * Search the bitmap for a free descriptor starting at minfd. 1812 * If none is found, grow the file table. 1813 */ 1814 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1815 if (fd >= maxfd) 1816 return (EMFILE); 1817 if (fd >= fdp->fd_nfiles) { 1818 allocfd = min(fd * 2, maxfd); 1819 #ifdef RACCT 1820 if (RACCT_ENABLED()) { 1821 error = racct_set_unlocked(p, RACCT_NOFILE, allocfd); 1822 if (error != 0) 1823 return (EMFILE); 1824 } 1825 #endif 1826 /* 1827 * fd is already equal to first free descriptor >= minfd, so 1828 * we only need to grow the table and we are done. 1829 */ 1830 fdgrowtable_exp(fdp, allocfd); 1831 } 1832 1833 /* 1834 * Perform some sanity checks, then mark the file descriptor as 1835 * used and return it to the caller. 1836 */ 1837 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1838 ("invalid descriptor %d", fd)); 1839 KASSERT(!fdisused(fdp, fd), 1840 ("fd_first_free() returned non-free descriptor")); 1841 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1842 ("file descriptor isn't free")); 1843 fdused(fdp, fd); 1844 *result = fd; 1845 return (0); 1846 } 1847 1848 /* 1849 * Allocate n file descriptors for the process. 1850 */ 1851 int 1852 fdallocn(struct thread *td, int minfd, int *fds, int n) 1853 { 1854 struct proc *p = td->td_proc; 1855 struct filedesc *fdp = p->p_fd; 1856 int i; 1857 1858 FILEDESC_XLOCK_ASSERT(fdp); 1859 1860 for (i = 0; i < n; i++) 1861 if (fdalloc(td, 0, &fds[i]) != 0) 1862 break; 1863 1864 if (i < n) { 1865 for (i--; i >= 0; i--) 1866 fdunused(fdp, fds[i]); 1867 return (EMFILE); 1868 } 1869 1870 return (0); 1871 } 1872 1873 /* 1874 * Create a new open file structure and allocate a file descriptor for the 1875 * process that refers to it. We add one reference to the file for the 1876 * descriptor table and one reference for resultfp. This is to prevent us 1877 * being preempted and the entry in the descriptor table closed after we 1878 * release the FILEDESC lock. 1879 */ 1880 int 1881 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags, 1882 struct filecaps *fcaps) 1883 { 1884 struct file *fp; 1885 int error, fd; 1886 1887 error = falloc_noinstall(td, &fp); 1888 if (error) 1889 return (error); /* no reference held on error */ 1890 1891 error = finstall(td, fp, &fd, flags, fcaps); 1892 if (error) { 1893 fdrop(fp, td); /* one reference (fp only) */ 1894 return (error); 1895 } 1896 1897 if (resultfp != NULL) 1898 *resultfp = fp; /* copy out result */ 1899 else 1900 fdrop(fp, td); /* release local reference */ 1901 1902 if (resultfd != NULL) 1903 *resultfd = fd; 1904 1905 return (0); 1906 } 1907 1908 /* 1909 * Create a new open file structure without allocating a file descriptor. 1910 */ 1911 int 1912 falloc_noinstall(struct thread *td, struct file **resultfp) 1913 { 1914 struct file *fp; 1915 int maxuserfiles = maxfiles - (maxfiles / 20); 1916 int openfiles_new; 1917 static struct timeval lastfail; 1918 static int curfail; 1919 1920 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1921 1922 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1; 1923 if ((openfiles_new >= maxuserfiles && 1924 priv_check(td, PRIV_MAXFILES) != 0) || 1925 openfiles_new >= maxfiles) { 1926 atomic_subtract_int(&openfiles, 1); 1927 if (ppsratecheck(&lastfail, &curfail, 1)) { 1928 printf("kern.maxfiles limit exceeded by uid %i, (%s) " 1929 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm); 1930 } 1931 return (ENFILE); 1932 } 1933 fp = uma_zalloc(file_zone, M_WAITOK); 1934 bzero(fp, sizeof(*fp)); 1935 refcount_init(&fp->f_count, 1); 1936 fp->f_cred = crhold(td->td_ucred); 1937 fp->f_ops = &badfileops; 1938 *resultfp = fp; 1939 return (0); 1940 } 1941 1942 /* 1943 * Install a file in a file descriptor table. 1944 */ 1945 void 1946 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags, 1947 struct filecaps *fcaps) 1948 { 1949 struct filedescent *fde; 1950 1951 MPASS(fp != NULL); 1952 if (fcaps != NULL) 1953 filecaps_validate(fcaps, __func__); 1954 FILEDESC_XLOCK_ASSERT(fdp); 1955 1956 fde = &fdp->fd_ofiles[fd]; 1957 #ifdef CAPABILITIES 1958 seqc_write_begin(&fde->fde_seqc); 1959 #endif 1960 fde->fde_file = fp; 1961 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0; 1962 if (fcaps != NULL) 1963 filecaps_move(fcaps, &fde->fde_caps); 1964 else 1965 filecaps_fill(&fde->fde_caps); 1966 #ifdef CAPABILITIES 1967 seqc_write_end(&fde->fde_seqc); 1968 #endif 1969 } 1970 1971 int 1972 finstall(struct thread *td, struct file *fp, int *fd, int flags, 1973 struct filecaps *fcaps) 1974 { 1975 struct filedesc *fdp = td->td_proc->p_fd; 1976 int error; 1977 1978 MPASS(fd != NULL); 1979 1980 if (!fhold(fp)) 1981 return (EBADF); 1982 FILEDESC_XLOCK(fdp); 1983 if ((error = fdalloc(td, 0, fd))) { 1984 FILEDESC_XUNLOCK(fdp); 1985 fdrop(fp, td); 1986 return (error); 1987 } 1988 _finstall(fdp, fp, *fd, flags, fcaps); 1989 FILEDESC_XUNLOCK(fdp); 1990 return (0); 1991 } 1992 1993 /* 1994 * Build a new filedesc structure from another. 1995 * Copy the current, root, and jail root vnode references. 1996 * 1997 * If fdp is not NULL, return with it shared locked. 1998 */ 1999 struct filedesc * 2000 fdinit(struct filedesc *fdp, bool prepfiles) 2001 { 2002 struct filedesc0 *newfdp0; 2003 struct filedesc *newfdp; 2004 2005 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO); 2006 newfdp = &newfdp0->fd_fd; 2007 2008 /* Create the file descriptor table. */ 2009 FILEDESC_LOCK_INIT(newfdp); 2010 refcount_init(&newfdp->fd_refcnt, 1); 2011 refcount_init(&newfdp->fd_holdcnt, 1); 2012 newfdp->fd_cmask = CMASK; 2013 newfdp->fd_map = newfdp0->fd_dmap; 2014 newfdp->fd_lastfile = -1; 2015 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles; 2016 newfdp->fd_files->fdt_nfiles = NDFILE; 2017 2018 if (fdp == NULL) 2019 return (newfdp); 2020 2021 if (prepfiles && fdp->fd_lastfile >= newfdp->fd_nfiles) 2022 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 2023 2024 FILEDESC_SLOCK(fdp); 2025 newfdp->fd_cdir = fdp->fd_cdir; 2026 if (newfdp->fd_cdir) 2027 vrefact(newfdp->fd_cdir); 2028 newfdp->fd_rdir = fdp->fd_rdir; 2029 if (newfdp->fd_rdir) 2030 vrefact(newfdp->fd_rdir); 2031 newfdp->fd_jdir = fdp->fd_jdir; 2032 if (newfdp->fd_jdir) 2033 vrefact(newfdp->fd_jdir); 2034 2035 if (!prepfiles) { 2036 FILEDESC_SUNLOCK(fdp); 2037 } else { 2038 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 2039 FILEDESC_SUNLOCK(fdp); 2040 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 2041 FILEDESC_SLOCK(fdp); 2042 } 2043 } 2044 2045 return (newfdp); 2046 } 2047 2048 static struct filedesc * 2049 fdhold(struct proc *p) 2050 { 2051 struct filedesc *fdp; 2052 2053 PROC_LOCK_ASSERT(p, MA_OWNED); 2054 fdp = p->p_fd; 2055 if (fdp != NULL) 2056 refcount_acquire(&fdp->fd_holdcnt); 2057 return (fdp); 2058 } 2059 2060 static void 2061 fddrop(struct filedesc *fdp) 2062 { 2063 2064 if (fdp->fd_holdcnt > 1) { 2065 if (refcount_release(&fdp->fd_holdcnt) == 0) 2066 return; 2067 } 2068 2069 FILEDESC_LOCK_DESTROY(fdp); 2070 uma_zfree(filedesc0_zone, fdp); 2071 } 2072 2073 /* 2074 * Share a filedesc structure. 2075 */ 2076 struct filedesc * 2077 fdshare(struct filedesc *fdp) 2078 { 2079 2080 refcount_acquire(&fdp->fd_refcnt); 2081 return (fdp); 2082 } 2083 2084 /* 2085 * Unshare a filedesc structure, if necessary by making a copy 2086 */ 2087 void 2088 fdunshare(struct thread *td) 2089 { 2090 struct filedesc *tmp; 2091 struct proc *p = td->td_proc; 2092 2093 if (p->p_fd->fd_refcnt == 1) 2094 return; 2095 2096 tmp = fdcopy(p->p_fd); 2097 fdescfree(td); 2098 p->p_fd = tmp; 2099 } 2100 2101 void 2102 fdinstall_remapped(struct thread *td, struct filedesc *fdp) 2103 { 2104 2105 fdescfree(td); 2106 td->td_proc->p_fd = fdp; 2107 } 2108 2109 /* 2110 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 2111 * this is to ease callers, not catch errors. 2112 */ 2113 struct filedesc * 2114 fdcopy(struct filedesc *fdp) 2115 { 2116 struct filedesc *newfdp; 2117 struct filedescent *nfde, *ofde; 2118 int i; 2119 2120 MPASS(fdp != NULL); 2121 2122 newfdp = fdinit(fdp, true); 2123 /* copy all passable descriptors (i.e. not kqueue) */ 2124 newfdp->fd_freefile = -1; 2125 for (i = 0; i <= fdp->fd_lastfile; ++i) { 2126 ofde = &fdp->fd_ofiles[i]; 2127 if (ofde->fde_file == NULL || 2128 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0 || 2129 !fhold(ofde->fde_file)) { 2130 if (newfdp->fd_freefile == -1) 2131 newfdp->fd_freefile = i; 2132 continue; 2133 } 2134 nfde = &newfdp->fd_ofiles[i]; 2135 *nfde = *ofde; 2136 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 2137 fdused_init(newfdp, i); 2138 newfdp->fd_lastfile = i; 2139 } 2140 if (newfdp->fd_freefile == -1) 2141 newfdp->fd_freefile = i; 2142 newfdp->fd_cmask = fdp->fd_cmask; 2143 FILEDESC_SUNLOCK(fdp); 2144 return (newfdp); 2145 } 2146 2147 /* 2148 * Copies a filedesc structure, while remapping all file descriptors 2149 * stored inside using a translation table. 2150 * 2151 * File descriptors are copied over to the new file descriptor table, 2152 * regardless of whether the close-on-exec flag is set. 2153 */ 2154 int 2155 fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds, 2156 struct filedesc **ret) 2157 { 2158 struct filedesc *newfdp; 2159 struct filedescent *nfde, *ofde; 2160 int error, i; 2161 2162 MPASS(fdp != NULL); 2163 2164 newfdp = fdinit(fdp, true); 2165 if (nfds > fdp->fd_lastfile + 1) { 2166 /* New table cannot be larger than the old one. */ 2167 error = E2BIG; 2168 goto bad; 2169 } 2170 /* Copy all passable descriptors (i.e. not kqueue). */ 2171 newfdp->fd_freefile = nfds; 2172 for (i = 0; i < nfds; ++i) { 2173 if (fds[i] < 0 || fds[i] > fdp->fd_lastfile) { 2174 /* File descriptor out of bounds. */ 2175 error = EBADF; 2176 goto bad; 2177 } 2178 ofde = &fdp->fd_ofiles[fds[i]]; 2179 if (ofde->fde_file == NULL) { 2180 /* Unused file descriptor. */ 2181 error = EBADF; 2182 goto bad; 2183 } 2184 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) { 2185 /* File descriptor cannot be passed. */ 2186 error = EINVAL; 2187 goto bad; 2188 } 2189 if (!fhold(nfde->fde_file)) { 2190 error = EBADF; 2191 goto bad; 2192 } 2193 nfde = &newfdp->fd_ofiles[i]; 2194 *nfde = *ofde; 2195 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 2196 fdused_init(newfdp, i); 2197 newfdp->fd_lastfile = i; 2198 } 2199 newfdp->fd_cmask = fdp->fd_cmask; 2200 FILEDESC_SUNLOCK(fdp); 2201 *ret = newfdp; 2202 return (0); 2203 bad: 2204 FILEDESC_SUNLOCK(fdp); 2205 fdescfree_remapped(newfdp); 2206 return (error); 2207 } 2208 2209 /* 2210 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e. 2211 * one of processes using it exits) and the table used to be shared. 2212 */ 2213 static void 2214 fdclearlocks(struct thread *td) 2215 { 2216 struct filedesc *fdp; 2217 struct filedesc_to_leader *fdtol; 2218 struct flock lf; 2219 struct file *fp; 2220 struct proc *p; 2221 struct vnode *vp; 2222 int i; 2223 2224 p = td->td_proc; 2225 fdp = p->p_fd; 2226 fdtol = p->p_fdtol; 2227 MPASS(fdtol != NULL); 2228 2229 FILEDESC_XLOCK(fdp); 2230 KASSERT(fdtol->fdl_refcount > 0, 2231 ("filedesc_to_refcount botch: fdl_refcount=%d", 2232 fdtol->fdl_refcount)); 2233 if (fdtol->fdl_refcount == 1 && 2234 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2235 for (i = 0; i <= fdp->fd_lastfile; i++) { 2236 fp = fdp->fd_ofiles[i].fde_file; 2237 if (fp == NULL || fp->f_type != DTYPE_VNODE || 2238 !fhold(fp)) 2239 continue; 2240 FILEDESC_XUNLOCK(fdp); 2241 lf.l_whence = SEEK_SET; 2242 lf.l_start = 0; 2243 lf.l_len = 0; 2244 lf.l_type = F_UNLCK; 2245 vp = fp->f_vnode; 2246 (void) VOP_ADVLOCK(vp, 2247 (caddr_t)p->p_leader, F_UNLCK, 2248 &lf, F_POSIX); 2249 FILEDESC_XLOCK(fdp); 2250 fdrop(fp, td); 2251 } 2252 } 2253 retry: 2254 if (fdtol->fdl_refcount == 1) { 2255 if (fdp->fd_holdleaderscount > 0 && 2256 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2257 /* 2258 * close() or kern_dup() has cleared a reference 2259 * in a shared file descriptor table. 2260 */ 2261 fdp->fd_holdleaderswakeup = 1; 2262 sx_sleep(&fdp->fd_holdleaderscount, 2263 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2264 goto retry; 2265 } 2266 if (fdtol->fdl_holdcount > 0) { 2267 /* 2268 * Ensure that fdtol->fdl_leader remains 2269 * valid in closef(). 2270 */ 2271 fdtol->fdl_wakeup = 1; 2272 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2273 "fdlhold", 0); 2274 goto retry; 2275 } 2276 } 2277 fdtol->fdl_refcount--; 2278 if (fdtol->fdl_refcount == 0 && 2279 fdtol->fdl_holdcount == 0) { 2280 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2281 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2282 } else 2283 fdtol = NULL; 2284 p->p_fdtol = NULL; 2285 FILEDESC_XUNLOCK(fdp); 2286 if (fdtol != NULL) 2287 free(fdtol, M_FILEDESC_TO_LEADER); 2288 } 2289 2290 /* 2291 * Release a filedesc structure. 2292 */ 2293 static void 2294 fdescfree_fds(struct thread *td, struct filedesc *fdp, bool needclose) 2295 { 2296 struct filedesc0 *fdp0; 2297 struct freetable *ft, *tft; 2298 struct filedescent *fde; 2299 struct file *fp; 2300 int i; 2301 2302 for (i = 0; i <= fdp->fd_lastfile; i++) { 2303 fde = &fdp->fd_ofiles[i]; 2304 fp = fde->fde_file; 2305 if (fp != NULL) { 2306 fdefree_last(fde); 2307 if (needclose) 2308 (void) closef(fp, td); 2309 else 2310 fdrop(fp, td); 2311 } 2312 } 2313 2314 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2315 free(fdp->fd_map, M_FILEDESC); 2316 if (fdp->fd_nfiles > NDFILE) 2317 free(fdp->fd_files, M_FILEDESC); 2318 2319 fdp0 = (struct filedesc0 *)fdp; 2320 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft) 2321 free(ft->ft_table, M_FILEDESC); 2322 2323 fddrop(fdp); 2324 } 2325 2326 void 2327 fdescfree(struct thread *td) 2328 { 2329 struct proc *p; 2330 struct filedesc *fdp; 2331 struct vnode *cdir, *jdir, *rdir; 2332 2333 p = td->td_proc; 2334 fdp = p->p_fd; 2335 MPASS(fdp != NULL); 2336 2337 #ifdef RACCT 2338 if (RACCT_ENABLED()) 2339 racct_set_unlocked(p, RACCT_NOFILE, 0); 2340 #endif 2341 2342 if (p->p_fdtol != NULL) 2343 fdclearlocks(td); 2344 2345 PROC_LOCK(p); 2346 p->p_fd = NULL; 2347 PROC_UNLOCK(p); 2348 2349 if (refcount_release(&fdp->fd_refcnt) == 0) 2350 return; 2351 2352 FILEDESC_XLOCK(fdp); 2353 cdir = fdp->fd_cdir; 2354 fdp->fd_cdir = NULL; 2355 rdir = fdp->fd_rdir; 2356 fdp->fd_rdir = NULL; 2357 jdir = fdp->fd_jdir; 2358 fdp->fd_jdir = NULL; 2359 FILEDESC_XUNLOCK(fdp); 2360 2361 if (cdir != NULL) 2362 vrele(cdir); 2363 if (rdir != NULL) 2364 vrele(rdir); 2365 if (jdir != NULL) 2366 vrele(jdir); 2367 2368 fdescfree_fds(td, fdp, 1); 2369 } 2370 2371 void 2372 fdescfree_remapped(struct filedesc *fdp) 2373 { 2374 2375 if (fdp->fd_cdir != NULL) 2376 vrele(fdp->fd_cdir); 2377 if (fdp->fd_rdir != NULL) 2378 vrele(fdp->fd_rdir); 2379 if (fdp->fd_jdir != NULL) 2380 vrele(fdp->fd_jdir); 2381 2382 fdescfree_fds(curthread, fdp, 0); 2383 } 2384 2385 /* 2386 * For setugid programs, we don't want to people to use that setugidness 2387 * to generate error messages which write to a file which otherwise would 2388 * otherwise be off-limits to the process. We check for filesystems where 2389 * the vnode can change out from under us after execve (like [lin]procfs). 2390 * 2391 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is 2392 * sufficient. We also don't check for setugidness since we know we are. 2393 */ 2394 static bool 2395 is_unsafe(struct file *fp) 2396 { 2397 struct vnode *vp; 2398 2399 if (fp->f_type != DTYPE_VNODE) 2400 return (false); 2401 2402 vp = fp->f_vnode; 2403 return ((vp->v_vflag & VV_PROCDEP) != 0); 2404 } 2405 2406 /* 2407 * Make this setguid thing safe, if at all possible. 2408 */ 2409 void 2410 fdsetugidsafety(struct thread *td) 2411 { 2412 struct filedesc *fdp; 2413 struct file *fp; 2414 int i; 2415 2416 fdp = td->td_proc->p_fd; 2417 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2418 MPASS(fdp->fd_nfiles >= 3); 2419 for (i = 0; i <= 2; i++) { 2420 fp = fdp->fd_ofiles[i].fde_file; 2421 if (fp != NULL && is_unsafe(fp)) { 2422 FILEDESC_XLOCK(fdp); 2423 knote_fdclose(td, i); 2424 /* 2425 * NULL-out descriptor prior to close to avoid 2426 * a race while close blocks. 2427 */ 2428 fdfree(fdp, i); 2429 FILEDESC_XUNLOCK(fdp); 2430 (void) closef(fp, td); 2431 } 2432 } 2433 } 2434 2435 /* 2436 * If a specific file object occupies a specific file descriptor, close the 2437 * file descriptor entry and drop a reference on the file object. This is a 2438 * convenience function to handle a subsequent error in a function that calls 2439 * falloc() that handles the race that another thread might have closed the 2440 * file descriptor out from under the thread creating the file object. 2441 */ 2442 void 2443 fdclose(struct thread *td, struct file *fp, int idx) 2444 { 2445 struct filedesc *fdp = td->td_proc->p_fd; 2446 2447 FILEDESC_XLOCK(fdp); 2448 if (fdp->fd_ofiles[idx].fde_file == fp) { 2449 fdfree(fdp, idx); 2450 FILEDESC_XUNLOCK(fdp); 2451 fdrop(fp, td); 2452 } else 2453 FILEDESC_XUNLOCK(fdp); 2454 } 2455 2456 /* 2457 * Close any files on exec? 2458 */ 2459 void 2460 fdcloseexec(struct thread *td) 2461 { 2462 struct filedesc *fdp; 2463 struct filedescent *fde; 2464 struct file *fp; 2465 int i; 2466 2467 fdp = td->td_proc->p_fd; 2468 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2469 for (i = 0; i <= fdp->fd_lastfile; i++) { 2470 fde = &fdp->fd_ofiles[i]; 2471 fp = fde->fde_file; 2472 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2473 (fde->fde_flags & UF_EXCLOSE))) { 2474 FILEDESC_XLOCK(fdp); 2475 fdfree(fdp, i); 2476 (void) closefp(fdp, i, fp, td, 0); 2477 FILEDESC_UNLOCK_ASSERT(fdp); 2478 } 2479 } 2480 } 2481 2482 /* 2483 * It is unsafe for set[ug]id processes to be started with file 2484 * descriptors 0..2 closed, as these descriptors are given implicit 2485 * significance in the Standard C library. fdcheckstd() will create a 2486 * descriptor referencing /dev/null for each of stdin, stdout, and 2487 * stderr that is not already open. 2488 */ 2489 int 2490 fdcheckstd(struct thread *td) 2491 { 2492 struct filedesc *fdp; 2493 register_t save; 2494 int i, error, devnull; 2495 2496 fdp = td->td_proc->p_fd; 2497 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2498 MPASS(fdp->fd_nfiles >= 3); 2499 devnull = -1; 2500 for (i = 0; i <= 2; i++) { 2501 if (fdp->fd_ofiles[i].fde_file != NULL) 2502 continue; 2503 2504 save = td->td_retval[0]; 2505 if (devnull != -1) { 2506 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i); 2507 } else { 2508 error = kern_openat(td, AT_FDCWD, "/dev/null", 2509 UIO_SYSSPACE, O_RDWR, 0); 2510 if (error == 0) { 2511 devnull = td->td_retval[0]; 2512 KASSERT(devnull == i, ("we didn't get our fd")); 2513 } 2514 } 2515 td->td_retval[0] = save; 2516 if (error != 0) 2517 return (error); 2518 } 2519 return (0); 2520 } 2521 2522 /* 2523 * Internal form of close. Decrement reference count on file structure. 2524 * Note: td may be NULL when closing a file that was being passed in a 2525 * message. 2526 */ 2527 int 2528 closef(struct file *fp, struct thread *td) 2529 { 2530 struct vnode *vp; 2531 struct flock lf; 2532 struct filedesc_to_leader *fdtol; 2533 struct filedesc *fdp; 2534 2535 /* 2536 * POSIX record locking dictates that any close releases ALL 2537 * locks owned by this process. This is handled by setting 2538 * a flag in the unlock to free ONLY locks obeying POSIX 2539 * semantics, and not to free BSD-style file locks. 2540 * If the descriptor was in a message, POSIX-style locks 2541 * aren't passed with the descriptor, and the thread pointer 2542 * will be NULL. Callers should be careful only to pass a 2543 * NULL thread pointer when there really is no owning 2544 * context that might have locks, or the locks will be 2545 * leaked. 2546 */ 2547 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2548 vp = fp->f_vnode; 2549 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2550 lf.l_whence = SEEK_SET; 2551 lf.l_start = 0; 2552 lf.l_len = 0; 2553 lf.l_type = F_UNLCK; 2554 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2555 F_UNLCK, &lf, F_POSIX); 2556 } 2557 fdtol = td->td_proc->p_fdtol; 2558 if (fdtol != NULL) { 2559 /* 2560 * Handle special case where file descriptor table is 2561 * shared between multiple process leaders. 2562 */ 2563 fdp = td->td_proc->p_fd; 2564 FILEDESC_XLOCK(fdp); 2565 for (fdtol = fdtol->fdl_next; 2566 fdtol != td->td_proc->p_fdtol; 2567 fdtol = fdtol->fdl_next) { 2568 if ((fdtol->fdl_leader->p_flag & 2569 P_ADVLOCK) == 0) 2570 continue; 2571 fdtol->fdl_holdcount++; 2572 FILEDESC_XUNLOCK(fdp); 2573 lf.l_whence = SEEK_SET; 2574 lf.l_start = 0; 2575 lf.l_len = 0; 2576 lf.l_type = F_UNLCK; 2577 vp = fp->f_vnode; 2578 (void) VOP_ADVLOCK(vp, 2579 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2580 F_POSIX); 2581 FILEDESC_XLOCK(fdp); 2582 fdtol->fdl_holdcount--; 2583 if (fdtol->fdl_holdcount == 0 && 2584 fdtol->fdl_wakeup != 0) { 2585 fdtol->fdl_wakeup = 0; 2586 wakeup(fdtol); 2587 } 2588 } 2589 FILEDESC_XUNLOCK(fdp); 2590 } 2591 } 2592 return (fdrop(fp, td)); 2593 } 2594 2595 /* 2596 * Initialize the file pointer with the specified properties. 2597 * 2598 * The ops are set with release semantics to be certain that the flags, type, 2599 * and data are visible when ops is. This is to prevent ops methods from being 2600 * called with bad data. 2601 */ 2602 void 2603 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2604 { 2605 fp->f_data = data; 2606 fp->f_flag = flag; 2607 fp->f_type = type; 2608 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2609 } 2610 2611 int 2612 fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2613 struct file **fpp, struct filecaps *havecapsp) 2614 { 2615 struct filedescent *fde; 2616 int error; 2617 2618 FILEDESC_LOCK_ASSERT(fdp); 2619 2620 fde = fdeget_locked(fdp, fd); 2621 if (fde == NULL) { 2622 error = EBADF; 2623 goto out; 2624 } 2625 2626 #ifdef CAPABILITIES 2627 error = cap_check(cap_rights_fde_inline(fde), needrightsp); 2628 if (error != 0) 2629 goto out; 2630 #endif 2631 2632 if (havecapsp != NULL) 2633 filecaps_copy(&fde->fde_caps, havecapsp, true); 2634 2635 *fpp = fde->fde_file; 2636 2637 error = 0; 2638 out: 2639 return (error); 2640 } 2641 2642 int 2643 fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp, 2644 struct file **fpp, struct filecaps *havecapsp) 2645 { 2646 struct filedesc *fdp = td->td_proc->p_fd; 2647 int error; 2648 #ifndef CAPABILITIES 2649 error = fget_unlocked(fdp, fd, needrightsp, fpp, NULL); 2650 if (error == 0 && havecapsp != NULL) 2651 filecaps_fill(havecapsp); 2652 #else 2653 struct file *fp; 2654 seqc_t seq; 2655 2656 for (;;) { 2657 error = fget_unlocked(fdp, fd, needrightsp, &fp, &seq); 2658 if (error != 0) 2659 return (error); 2660 2661 if (havecapsp != NULL) { 2662 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, 2663 havecapsp, false)) { 2664 fdrop(fp, td); 2665 goto get_locked; 2666 } 2667 } 2668 2669 if (!fd_modified(fdp, fd, seq)) 2670 break; 2671 fdrop(fp, td); 2672 } 2673 2674 *fpp = fp; 2675 return (0); 2676 2677 get_locked: 2678 FILEDESC_SLOCK(fdp); 2679 error = fget_cap_locked(fdp, fd, needrightsp, fpp, havecapsp); 2680 if (error == 0 && !fhold(*fpp)) 2681 error = EBADF; 2682 FILEDESC_SUNLOCK(fdp); 2683 #endif 2684 return (error); 2685 } 2686 2687 int 2688 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2689 struct file **fpp, seqc_t *seqp) 2690 { 2691 #ifdef CAPABILITIES 2692 const struct filedescent *fde; 2693 #endif 2694 const struct fdescenttbl *fdt; 2695 struct file *fp; 2696 u_int count; 2697 #ifdef CAPABILITIES 2698 seqc_t seq; 2699 cap_rights_t haverights; 2700 int error; 2701 #endif 2702 2703 fdt = fdp->fd_files; 2704 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 2705 return (EBADF); 2706 /* 2707 * Fetch the descriptor locklessly. We avoid fdrop() races by 2708 * never raising a refcount above 0. To accomplish this we have 2709 * to use a cmpset loop rather than an atomic_add. The descriptor 2710 * must be re-verified once we acquire a reference to be certain 2711 * that the identity is still correct and we did not lose a race 2712 * due to preemption. 2713 */ 2714 for (;;) { 2715 #ifdef CAPABILITIES 2716 seq = seqc_read(fd_seqc(fdt, fd)); 2717 fde = &fdt->fdt_ofiles[fd]; 2718 haverights = *cap_rights_fde_inline(fde); 2719 fp = fde->fde_file; 2720 if (!seqc_consistent(fd_seqc(fdt, fd), seq)) 2721 continue; 2722 #else 2723 fp = fdt->fdt_ofiles[fd].fde_file; 2724 #endif 2725 if (fp == NULL) 2726 return (EBADF); 2727 #ifdef CAPABILITIES 2728 error = cap_check(&haverights, needrightsp); 2729 if (error != 0) 2730 return (error); 2731 #endif 2732 count = fp->f_count; 2733 retry: 2734 if (count == 0) { 2735 /* 2736 * Force a reload. Other thread could reallocate the 2737 * table before this fd was closed, so it possible that 2738 * there is a stale fp pointer in cached version. 2739 */ 2740 fdt = *(const struct fdescenttbl * const volatile *) 2741 &(fdp->fd_files); 2742 continue; 2743 } 2744 if (__predict_false(count + 1 < count)) 2745 return (EBADF); 2746 2747 /* 2748 * Use an acquire barrier to force re-reading of fdt so it is 2749 * refreshed for verification. 2750 */ 2751 if (__predict_false(atomic_fcmpset_acq_int(&fp->f_count, 2752 &count, count + 1) == 0)) 2753 goto retry; 2754 fdt = fdp->fd_files; 2755 #ifdef CAPABILITIES 2756 if (seqc_consistent_nomb(fd_seqc(fdt, fd), seq)) 2757 #else 2758 if (fp == fdt->fdt_ofiles[fd].fde_file) 2759 #endif 2760 break; 2761 fdrop(fp, curthread); 2762 } 2763 *fpp = fp; 2764 if (seqp != NULL) { 2765 #ifdef CAPABILITIES 2766 *seqp = seq; 2767 #endif 2768 } 2769 return (0); 2770 } 2771 2772 /* 2773 * Extract the file pointer associated with the specified descriptor for the 2774 * current user process. 2775 * 2776 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2777 * returned. 2778 * 2779 * File's rights will be checked against the capability rights mask. 2780 * 2781 * If an error occurred the non-zero error is returned and *fpp is set to 2782 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2783 * responsible for fdrop(). 2784 */ 2785 static __inline int 2786 _fget(struct thread *td, int fd, struct file **fpp, int flags, 2787 cap_rights_t *needrightsp, seqc_t *seqp) 2788 { 2789 struct filedesc *fdp; 2790 struct file *fp; 2791 int error; 2792 2793 *fpp = NULL; 2794 fdp = td->td_proc->p_fd; 2795 error = fget_unlocked(fdp, fd, needrightsp, &fp, seqp); 2796 if (error != 0) 2797 return (error); 2798 if (fp->f_ops == &badfileops) { 2799 fdrop(fp, td); 2800 return (EBADF); 2801 } 2802 2803 /* 2804 * FREAD and FWRITE failure return EBADF as per POSIX. 2805 */ 2806 error = 0; 2807 switch (flags) { 2808 case FREAD: 2809 case FWRITE: 2810 if ((fp->f_flag & flags) == 0) 2811 error = EBADF; 2812 break; 2813 case FEXEC: 2814 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2815 ((fp->f_flag & FWRITE) != 0)) 2816 error = EBADF; 2817 break; 2818 case 0: 2819 break; 2820 default: 2821 KASSERT(0, ("wrong flags")); 2822 } 2823 2824 if (error != 0) { 2825 fdrop(fp, td); 2826 return (error); 2827 } 2828 2829 *fpp = fp; 2830 return (0); 2831 } 2832 2833 int 2834 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2835 { 2836 2837 return (_fget(td, fd, fpp, 0, rightsp, NULL)); 2838 } 2839 2840 int 2841 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2842 struct file **fpp) 2843 { 2844 int error; 2845 #ifndef CAPABILITIES 2846 error = _fget(td, fd, fpp, 0, rightsp, NULL); 2847 if (maxprotp != NULL) 2848 *maxprotp = VM_PROT_ALL; 2849 #else 2850 cap_rights_t fdrights; 2851 struct filedesc *fdp = td->td_proc->p_fd; 2852 seqc_t seq; 2853 2854 MPASS(cap_rights_is_set(rightsp, CAP_MMAP)); 2855 for (;;) { 2856 error = _fget(td, fd, fpp, 0, rightsp, &seq); 2857 if (error != 0) 2858 return (error); 2859 if (maxprotp != NULL) 2860 fdrights = *cap_rights(fdp, fd); 2861 if (!fd_modified(fdp, fd, seq)) 2862 break; 2863 fdrop(*fpp, td); 2864 } 2865 2866 /* 2867 * If requested, convert capability rights to access flags. 2868 */ 2869 if (maxprotp != NULL) 2870 *maxprotp = cap_rights_to_vmprot(&fdrights); 2871 #endif 2872 return (error); 2873 } 2874 2875 int 2876 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2877 { 2878 2879 return (_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2880 } 2881 2882 int 2883 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2884 { 2885 2886 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2887 } 2888 2889 int 2890 fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp, int needfcntl, 2891 struct file **fpp) 2892 { 2893 struct filedesc *fdp = td->td_proc->p_fd; 2894 #ifndef CAPABILITIES 2895 return (fget_unlocked(fdp, fd, rightsp, fpp, NULL)); 2896 #else 2897 int error; 2898 seqc_t seq; 2899 2900 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL)); 2901 for (;;) { 2902 error = fget_unlocked(fdp, fd, rightsp, fpp, &seq); 2903 if (error != 0) 2904 return (error); 2905 error = cap_fcntl_check(fdp, fd, needfcntl); 2906 if (!fd_modified(fdp, fd, seq)) 2907 break; 2908 fdrop(*fpp, td); 2909 } 2910 if (error != 0) { 2911 fdrop(*fpp, td); 2912 *fpp = NULL; 2913 } 2914 return (error); 2915 #endif 2916 } 2917 2918 /* 2919 * Like fget() but loads the underlying vnode, or returns an error if the 2920 * descriptor does not represent a vnode. Note that pipes use vnodes but 2921 * never have VM objects. The returned vnode will be vref()'d. 2922 * 2923 * XXX: what about the unused flags ? 2924 */ 2925 static __inline int 2926 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2927 struct vnode **vpp) 2928 { 2929 struct file *fp; 2930 int error; 2931 2932 *vpp = NULL; 2933 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2934 if (error != 0) 2935 return (error); 2936 if (fp->f_vnode == NULL) { 2937 error = EINVAL; 2938 } else { 2939 *vpp = fp->f_vnode; 2940 vrefact(*vpp); 2941 } 2942 fdrop(fp, td); 2943 2944 return (error); 2945 } 2946 2947 int 2948 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2949 { 2950 2951 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2952 } 2953 2954 int 2955 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2956 struct filecaps *havecaps, struct vnode **vpp) 2957 { 2958 struct filedesc *fdp; 2959 struct filecaps caps; 2960 struct file *fp; 2961 int error; 2962 2963 fdp = td->td_proc->p_fd; 2964 error = fget_cap_locked(fdp, fd, needrightsp, &fp, &caps); 2965 if (error != 0) 2966 return (error); 2967 if (fp->f_ops == &badfileops) { 2968 error = EBADF; 2969 goto out; 2970 } 2971 if (fp->f_vnode == NULL) { 2972 error = EINVAL; 2973 goto out; 2974 } 2975 2976 *havecaps = caps; 2977 *vpp = fp->f_vnode; 2978 vrefact(*vpp); 2979 2980 return (0); 2981 out: 2982 filecaps_free(&caps); 2983 return (error); 2984 } 2985 2986 int 2987 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2988 { 2989 2990 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2991 } 2992 2993 int 2994 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2995 { 2996 2997 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2998 } 2999 3000 #ifdef notyet 3001 int 3002 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 3003 struct vnode **vpp) 3004 { 3005 3006 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 3007 } 3008 #endif 3009 3010 /* 3011 * Handle the last reference to a file being closed. 3012 * 3013 * Without the noinline attribute clang keeps inlining the func thorough this 3014 * file when fdrop is used. 3015 */ 3016 int __noinline 3017 _fdrop(struct file *fp, struct thread *td) 3018 { 3019 int error; 3020 3021 if (fp->f_count != 0) 3022 panic("fdrop: count %d", fp->f_count); 3023 error = fo_close(fp, td); 3024 atomic_subtract_int(&openfiles, 1); 3025 crfree(fp->f_cred); 3026 free(fp->f_advice, M_FADVISE); 3027 uma_zfree(file_zone, fp); 3028 3029 return (error); 3030 } 3031 3032 /* 3033 * Apply an advisory lock on a file descriptor. 3034 * 3035 * Just attempt to get a record lock of the requested type on the entire file 3036 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 3037 */ 3038 #ifndef _SYS_SYSPROTO_H_ 3039 struct flock_args { 3040 int fd; 3041 int how; 3042 }; 3043 #endif 3044 /* ARGSUSED */ 3045 int 3046 sys_flock(struct thread *td, struct flock_args *uap) 3047 { 3048 struct file *fp; 3049 struct vnode *vp; 3050 struct flock lf; 3051 int error; 3052 3053 error = fget(td, uap->fd, &cap_flock_rights, &fp); 3054 if (error != 0) 3055 return (error); 3056 if (fp->f_type != DTYPE_VNODE) { 3057 fdrop(fp, td); 3058 return (EOPNOTSUPP); 3059 } 3060 3061 vp = fp->f_vnode; 3062 lf.l_whence = SEEK_SET; 3063 lf.l_start = 0; 3064 lf.l_len = 0; 3065 if (uap->how & LOCK_UN) { 3066 lf.l_type = F_UNLCK; 3067 atomic_clear_int(&fp->f_flag, FHASLOCK); 3068 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 3069 goto done2; 3070 } 3071 if (uap->how & LOCK_EX) 3072 lf.l_type = F_WRLCK; 3073 else if (uap->how & LOCK_SH) 3074 lf.l_type = F_RDLCK; 3075 else { 3076 error = EBADF; 3077 goto done2; 3078 } 3079 atomic_set_int(&fp->f_flag, FHASLOCK); 3080 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 3081 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 3082 done2: 3083 fdrop(fp, td); 3084 return (error); 3085 } 3086 /* 3087 * Duplicate the specified descriptor to a free descriptor. 3088 */ 3089 int 3090 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 3091 int openerror, int *indxp) 3092 { 3093 struct filedescent *newfde, *oldfde; 3094 struct file *fp; 3095 u_long *ioctls; 3096 int error, indx; 3097 3098 KASSERT(openerror == ENODEV || openerror == ENXIO, 3099 ("unexpected error %d in %s", openerror, __func__)); 3100 3101 /* 3102 * If the to-be-dup'd fd number is greater than the allowed number 3103 * of file descriptors, or the fd to be dup'd has already been 3104 * closed, then reject. 3105 */ 3106 FILEDESC_XLOCK(fdp); 3107 if ((fp = fget_locked(fdp, dfd)) == NULL) { 3108 FILEDESC_XUNLOCK(fdp); 3109 return (EBADF); 3110 } 3111 3112 error = fdalloc(td, 0, &indx); 3113 if (error != 0) { 3114 FILEDESC_XUNLOCK(fdp); 3115 return (error); 3116 } 3117 3118 /* 3119 * There are two cases of interest here. 3120 * 3121 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 3122 * 3123 * For ENXIO steal away the file structure from (dfd) and store it in 3124 * (indx). (dfd) is effectively closed by this operation. 3125 */ 3126 switch (openerror) { 3127 case ENODEV: 3128 /* 3129 * Check that the mode the file is being opened for is a 3130 * subset of the mode of the existing descriptor. 3131 */ 3132 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 3133 fdunused(fdp, indx); 3134 FILEDESC_XUNLOCK(fdp); 3135 return (EACCES); 3136 } 3137 if (!fhold(fp)) { 3138 fdunused(fdp, indx); 3139 FILEDESC_XUNLOCK(fdp); 3140 return (EBADF); 3141 } 3142 newfde = &fdp->fd_ofiles[indx]; 3143 oldfde = &fdp->fd_ofiles[dfd]; 3144 ioctls = filecaps_copy_prep(&oldfde->fde_caps); 3145 #ifdef CAPABILITIES 3146 seqc_write_begin(&newfde->fde_seqc); 3147 #endif 3148 memcpy(newfde, oldfde, fde_change_size); 3149 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps, 3150 ioctls); 3151 #ifdef CAPABILITIES 3152 seqc_write_end(&newfde->fde_seqc); 3153 #endif 3154 break; 3155 case ENXIO: 3156 /* 3157 * Steal away the file pointer from dfd and stuff it into indx. 3158 */ 3159 newfde = &fdp->fd_ofiles[indx]; 3160 oldfde = &fdp->fd_ofiles[dfd]; 3161 #ifdef CAPABILITIES 3162 seqc_write_begin(&newfde->fde_seqc); 3163 #endif 3164 memcpy(newfde, oldfde, fde_change_size); 3165 oldfde->fde_file = NULL; 3166 fdunused(fdp, dfd); 3167 #ifdef CAPABILITIES 3168 seqc_write_end(&newfde->fde_seqc); 3169 #endif 3170 break; 3171 } 3172 FILEDESC_XUNLOCK(fdp); 3173 *indxp = indx; 3174 return (0); 3175 } 3176 3177 /* 3178 * This sysctl determines if we will allow a process to chroot(2) if it 3179 * has a directory open: 3180 * 0: disallowed for all processes. 3181 * 1: allowed for processes that were not already chroot(2)'ed. 3182 * 2: allowed for all processes. 3183 */ 3184 3185 static int chroot_allow_open_directories = 1; 3186 3187 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW, 3188 &chroot_allow_open_directories, 0, 3189 "Allow a process to chroot(2) if it has a directory open"); 3190 3191 /* 3192 * Helper function for raised chroot(2) security function: Refuse if 3193 * any filedescriptors are open directories. 3194 */ 3195 static int 3196 chroot_refuse_vdir_fds(struct filedesc *fdp) 3197 { 3198 struct vnode *vp; 3199 struct file *fp; 3200 int fd; 3201 3202 FILEDESC_LOCK_ASSERT(fdp); 3203 3204 for (fd = 0; fd <= fdp->fd_lastfile; fd++) { 3205 fp = fget_locked(fdp, fd); 3206 if (fp == NULL) 3207 continue; 3208 if (fp->f_type == DTYPE_VNODE) { 3209 vp = fp->f_vnode; 3210 if (vp->v_type == VDIR) 3211 return (EPERM); 3212 } 3213 } 3214 return (0); 3215 } 3216 3217 /* 3218 * Common routine for kern_chroot() and jail_attach(). The caller is 3219 * responsible for invoking priv_check() and mac_vnode_check_chroot() to 3220 * authorize this operation. 3221 */ 3222 int 3223 pwd_chroot(struct thread *td, struct vnode *vp) 3224 { 3225 struct filedesc *fdp; 3226 struct vnode *oldvp; 3227 int error; 3228 3229 fdp = td->td_proc->p_fd; 3230 FILEDESC_XLOCK(fdp); 3231 if (chroot_allow_open_directories == 0 || 3232 (chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) { 3233 error = chroot_refuse_vdir_fds(fdp); 3234 if (error != 0) { 3235 FILEDESC_XUNLOCK(fdp); 3236 return (error); 3237 } 3238 } 3239 oldvp = fdp->fd_rdir; 3240 vrefact(vp); 3241 fdp->fd_rdir = vp; 3242 if (fdp->fd_jdir == NULL) { 3243 vrefact(vp); 3244 fdp->fd_jdir = vp; 3245 } 3246 FILEDESC_XUNLOCK(fdp); 3247 vrele(oldvp); 3248 return (0); 3249 } 3250 3251 void 3252 pwd_chdir(struct thread *td, struct vnode *vp) 3253 { 3254 struct filedesc *fdp; 3255 struct vnode *oldvp; 3256 3257 fdp = td->td_proc->p_fd; 3258 FILEDESC_XLOCK(fdp); 3259 VNASSERT(vp->v_usecount > 0, vp, 3260 ("chdir to a vnode with zero usecount")); 3261 oldvp = fdp->fd_cdir; 3262 fdp->fd_cdir = vp; 3263 FILEDESC_XUNLOCK(fdp); 3264 vrele(oldvp); 3265 } 3266 3267 /* 3268 * Scan all active processes and prisons to see if any of them have a current 3269 * or root directory of `olddp'. If so, replace them with the new mount point. 3270 */ 3271 void 3272 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 3273 { 3274 struct filedesc *fdp; 3275 struct prison *pr; 3276 struct proc *p; 3277 int nrele; 3278 3279 if (vrefcnt(olddp) == 1) 3280 return; 3281 nrele = 0; 3282 sx_slock(&allproc_lock); 3283 FOREACH_PROC_IN_SYSTEM(p) { 3284 PROC_LOCK(p); 3285 fdp = fdhold(p); 3286 PROC_UNLOCK(p); 3287 if (fdp == NULL) 3288 continue; 3289 FILEDESC_XLOCK(fdp); 3290 if (fdp->fd_cdir == olddp) { 3291 vrefact(newdp); 3292 fdp->fd_cdir = newdp; 3293 nrele++; 3294 } 3295 if (fdp->fd_rdir == olddp) { 3296 vrefact(newdp); 3297 fdp->fd_rdir = newdp; 3298 nrele++; 3299 } 3300 if (fdp->fd_jdir == olddp) { 3301 vrefact(newdp); 3302 fdp->fd_jdir = newdp; 3303 nrele++; 3304 } 3305 FILEDESC_XUNLOCK(fdp); 3306 fddrop(fdp); 3307 } 3308 sx_sunlock(&allproc_lock); 3309 if (rootvnode == olddp) { 3310 vrefact(newdp); 3311 rootvnode = newdp; 3312 nrele++; 3313 } 3314 mtx_lock(&prison0.pr_mtx); 3315 if (prison0.pr_root == olddp) { 3316 vrefact(newdp); 3317 prison0.pr_root = newdp; 3318 nrele++; 3319 } 3320 mtx_unlock(&prison0.pr_mtx); 3321 sx_slock(&allprison_lock); 3322 TAILQ_FOREACH(pr, &allprison, pr_list) { 3323 mtx_lock(&pr->pr_mtx); 3324 if (pr->pr_root == olddp) { 3325 vrefact(newdp); 3326 pr->pr_root = newdp; 3327 nrele++; 3328 } 3329 mtx_unlock(&pr->pr_mtx); 3330 } 3331 sx_sunlock(&allprison_lock); 3332 while (nrele--) 3333 vrele(olddp); 3334 } 3335 3336 struct filedesc_to_leader * 3337 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 3338 { 3339 struct filedesc_to_leader *fdtol; 3340 3341 fdtol = malloc(sizeof(struct filedesc_to_leader), 3342 M_FILEDESC_TO_LEADER, M_WAITOK); 3343 fdtol->fdl_refcount = 1; 3344 fdtol->fdl_holdcount = 0; 3345 fdtol->fdl_wakeup = 0; 3346 fdtol->fdl_leader = leader; 3347 if (old != NULL) { 3348 FILEDESC_XLOCK(fdp); 3349 fdtol->fdl_next = old->fdl_next; 3350 fdtol->fdl_prev = old; 3351 old->fdl_next = fdtol; 3352 fdtol->fdl_next->fdl_prev = fdtol; 3353 FILEDESC_XUNLOCK(fdp); 3354 } else { 3355 fdtol->fdl_next = fdtol; 3356 fdtol->fdl_prev = fdtol; 3357 } 3358 return (fdtol); 3359 } 3360 3361 static int 3362 sysctl_kern_proc_nfds(SYSCTL_HANDLER_ARGS) 3363 { 3364 struct filedesc *fdp; 3365 int i, count, slots; 3366 3367 if (*(int *)arg1 != 0) 3368 return (EINVAL); 3369 3370 fdp = curproc->p_fd; 3371 count = 0; 3372 FILEDESC_SLOCK(fdp); 3373 slots = NDSLOTS(fdp->fd_lastfile + 1); 3374 for (i = 0; i < slots; i++) 3375 count += bitcountl(fdp->fd_map[i]); 3376 FILEDESC_SUNLOCK(fdp); 3377 3378 return (SYSCTL_OUT(req, &count, sizeof(count))); 3379 } 3380 3381 static SYSCTL_NODE(_kern_proc, KERN_PROC_NFDS, nfds, 3382 CTLFLAG_RD|CTLFLAG_CAPRD|CTLFLAG_MPSAFE, sysctl_kern_proc_nfds, 3383 "Number of open file descriptors"); 3384 3385 /* 3386 * Get file structures globally. 3387 */ 3388 static int 3389 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 3390 { 3391 struct xfile xf; 3392 struct filedesc *fdp; 3393 struct file *fp; 3394 struct proc *p; 3395 int error, n; 3396 3397 error = sysctl_wire_old_buffer(req, 0); 3398 if (error != 0) 3399 return (error); 3400 if (req->oldptr == NULL) { 3401 n = 0; 3402 sx_slock(&allproc_lock); 3403 FOREACH_PROC_IN_SYSTEM(p) { 3404 PROC_LOCK(p); 3405 if (p->p_state == PRS_NEW) { 3406 PROC_UNLOCK(p); 3407 continue; 3408 } 3409 fdp = fdhold(p); 3410 PROC_UNLOCK(p); 3411 if (fdp == NULL) 3412 continue; 3413 /* overestimates sparse tables. */ 3414 if (fdp->fd_lastfile > 0) 3415 n += fdp->fd_lastfile; 3416 fddrop(fdp); 3417 } 3418 sx_sunlock(&allproc_lock); 3419 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 3420 } 3421 error = 0; 3422 bzero(&xf, sizeof(xf)); 3423 xf.xf_size = sizeof(xf); 3424 sx_slock(&allproc_lock); 3425 FOREACH_PROC_IN_SYSTEM(p) { 3426 PROC_LOCK(p); 3427 if (p->p_state == PRS_NEW) { 3428 PROC_UNLOCK(p); 3429 continue; 3430 } 3431 if (p_cansee(req->td, p) != 0) { 3432 PROC_UNLOCK(p); 3433 continue; 3434 } 3435 xf.xf_pid = p->p_pid; 3436 xf.xf_uid = p->p_ucred->cr_uid; 3437 fdp = fdhold(p); 3438 PROC_UNLOCK(p); 3439 if (fdp == NULL) 3440 continue; 3441 FILEDESC_SLOCK(fdp); 3442 for (n = 0; fdp->fd_refcnt > 0 && n <= fdp->fd_lastfile; ++n) { 3443 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3444 continue; 3445 xf.xf_fd = n; 3446 xf.xf_file = (uintptr_t)fp; 3447 xf.xf_data = (uintptr_t)fp->f_data; 3448 xf.xf_vnode = (uintptr_t)fp->f_vnode; 3449 xf.xf_type = (uintptr_t)fp->f_type; 3450 xf.xf_count = fp->f_count; 3451 xf.xf_msgcount = 0; 3452 xf.xf_offset = foffset_get(fp); 3453 xf.xf_flag = fp->f_flag; 3454 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 3455 if (error) 3456 break; 3457 } 3458 FILEDESC_SUNLOCK(fdp); 3459 fddrop(fdp); 3460 if (error) 3461 break; 3462 } 3463 sx_sunlock(&allproc_lock); 3464 return (error); 3465 } 3466 3467 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 3468 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 3469 3470 #ifdef KINFO_FILE_SIZE 3471 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3472 #endif 3473 3474 static int 3475 xlate_fflags(int fflags) 3476 { 3477 static const struct { 3478 int fflag; 3479 int kf_fflag; 3480 } fflags_table[] = { 3481 { FAPPEND, KF_FLAG_APPEND }, 3482 { FASYNC, KF_FLAG_ASYNC }, 3483 { FFSYNC, KF_FLAG_FSYNC }, 3484 { FHASLOCK, KF_FLAG_HASLOCK }, 3485 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3486 { FREAD, KF_FLAG_READ }, 3487 { FWRITE, KF_FLAG_WRITE }, 3488 { O_CREAT, KF_FLAG_CREAT }, 3489 { O_DIRECT, KF_FLAG_DIRECT }, 3490 { O_EXCL, KF_FLAG_EXCL }, 3491 { O_EXEC, KF_FLAG_EXEC }, 3492 { O_EXLOCK, KF_FLAG_EXLOCK }, 3493 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3494 { O_SHLOCK, KF_FLAG_SHLOCK }, 3495 { O_TRUNC, KF_FLAG_TRUNC } 3496 }; 3497 unsigned int i; 3498 int kflags; 3499 3500 kflags = 0; 3501 for (i = 0; i < nitems(fflags_table); i++) 3502 if (fflags & fflags_table[i].fflag) 3503 kflags |= fflags_table[i].kf_fflag; 3504 return (kflags); 3505 } 3506 3507 /* Trim unused data from kf_path by truncating the structure size. */ 3508 void 3509 pack_kinfo(struct kinfo_file *kif) 3510 { 3511 3512 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3513 strlen(kif->kf_path) + 1; 3514 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3515 } 3516 3517 static void 3518 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp, 3519 struct kinfo_file *kif, struct filedesc *fdp, int flags) 3520 { 3521 int error; 3522 3523 bzero(kif, sizeof(*kif)); 3524 3525 /* Set a default type to allow for empty fill_kinfo() methods. */ 3526 kif->kf_type = KF_TYPE_UNKNOWN; 3527 kif->kf_flags = xlate_fflags(fp->f_flag); 3528 if (rightsp != NULL) 3529 kif->kf_cap_rights = *rightsp; 3530 else 3531 cap_rights_init(&kif->kf_cap_rights); 3532 kif->kf_fd = fd; 3533 kif->kf_ref_count = fp->f_count; 3534 kif->kf_offset = foffset_get(fp); 3535 3536 /* 3537 * This may drop the filedesc lock, so the 'fp' cannot be 3538 * accessed after this call. 3539 */ 3540 error = fo_fill_kinfo(fp, kif, fdp); 3541 if (error == 0) 3542 kif->kf_status |= KF_ATTR_VALID; 3543 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 3544 pack_kinfo(kif); 3545 else 3546 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 3547 } 3548 3549 static void 3550 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags, 3551 struct kinfo_file *kif, int flags) 3552 { 3553 int error; 3554 3555 bzero(kif, sizeof(*kif)); 3556 3557 kif->kf_type = KF_TYPE_VNODE; 3558 error = vn_fill_kinfo_vnode(vp, kif); 3559 if (error == 0) 3560 kif->kf_status |= KF_ATTR_VALID; 3561 kif->kf_flags = xlate_fflags(fflags); 3562 cap_rights_init(&kif->kf_cap_rights); 3563 kif->kf_fd = fd; 3564 kif->kf_ref_count = -1; 3565 kif->kf_offset = -1; 3566 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 3567 pack_kinfo(kif); 3568 else 3569 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 3570 vrele(vp); 3571 } 3572 3573 struct export_fd_buf { 3574 struct filedesc *fdp; 3575 struct sbuf *sb; 3576 ssize_t remainder; 3577 struct kinfo_file kif; 3578 int flags; 3579 }; 3580 3581 static int 3582 export_kinfo_to_sb(struct export_fd_buf *efbuf) 3583 { 3584 struct kinfo_file *kif; 3585 3586 kif = &efbuf->kif; 3587 if (efbuf->remainder != -1) { 3588 if (efbuf->remainder < kif->kf_structsize) { 3589 /* Terminate export. */ 3590 efbuf->remainder = 0; 3591 return (0); 3592 } 3593 efbuf->remainder -= kif->kf_structsize; 3594 } 3595 return (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) == 0 ? 0 : ENOMEM); 3596 } 3597 3598 static int 3599 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp, 3600 struct export_fd_buf *efbuf) 3601 { 3602 int error; 3603 3604 if (efbuf->remainder == 0) 3605 return (0); 3606 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp, 3607 efbuf->flags); 3608 FILEDESC_SUNLOCK(efbuf->fdp); 3609 error = export_kinfo_to_sb(efbuf); 3610 FILEDESC_SLOCK(efbuf->fdp); 3611 return (error); 3612 } 3613 3614 static int 3615 export_vnode_to_sb(struct vnode *vp, int fd, int fflags, 3616 struct export_fd_buf *efbuf) 3617 { 3618 int error; 3619 3620 if (efbuf->remainder == 0) 3621 return (0); 3622 if (efbuf->fdp != NULL) 3623 FILEDESC_SUNLOCK(efbuf->fdp); 3624 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif, efbuf->flags); 3625 error = export_kinfo_to_sb(efbuf); 3626 if (efbuf->fdp != NULL) 3627 FILEDESC_SLOCK(efbuf->fdp); 3628 return (error); 3629 } 3630 3631 /* 3632 * Store a process file descriptor information to sbuf. 3633 * 3634 * Takes a locked proc as argument, and returns with the proc unlocked. 3635 */ 3636 int 3637 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen, 3638 int flags) 3639 { 3640 struct file *fp; 3641 struct filedesc *fdp; 3642 struct export_fd_buf *efbuf; 3643 struct vnode *cttyvp, *textvp, *tracevp; 3644 int error, i; 3645 cap_rights_t rights; 3646 3647 PROC_LOCK_ASSERT(p, MA_OWNED); 3648 3649 /* ktrace vnode */ 3650 tracevp = p->p_tracevp; 3651 if (tracevp != NULL) 3652 vrefact(tracevp); 3653 /* text vnode */ 3654 textvp = p->p_textvp; 3655 if (textvp != NULL) 3656 vrefact(textvp); 3657 /* Controlling tty. */ 3658 cttyvp = NULL; 3659 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3660 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3661 if (cttyvp != NULL) 3662 vrefact(cttyvp); 3663 } 3664 fdp = fdhold(p); 3665 PROC_UNLOCK(p); 3666 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3667 efbuf->fdp = NULL; 3668 efbuf->sb = sb; 3669 efbuf->remainder = maxlen; 3670 efbuf->flags = flags; 3671 if (tracevp != NULL) 3672 export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE, FREAD | FWRITE, 3673 efbuf); 3674 if (textvp != NULL) 3675 export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD, efbuf); 3676 if (cttyvp != NULL) 3677 export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY, FREAD | FWRITE, 3678 efbuf); 3679 error = 0; 3680 if (fdp == NULL) 3681 goto fail; 3682 efbuf->fdp = fdp; 3683 FILEDESC_SLOCK(fdp); 3684 /* working directory */ 3685 if (fdp->fd_cdir != NULL) { 3686 vrefact(fdp->fd_cdir); 3687 export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD, FREAD, efbuf); 3688 } 3689 /* root directory */ 3690 if (fdp->fd_rdir != NULL) { 3691 vrefact(fdp->fd_rdir); 3692 export_vnode_to_sb(fdp->fd_rdir, KF_FD_TYPE_ROOT, FREAD, efbuf); 3693 } 3694 /* jail directory */ 3695 if (fdp->fd_jdir != NULL) { 3696 vrefact(fdp->fd_jdir); 3697 export_vnode_to_sb(fdp->fd_jdir, KF_FD_TYPE_JAIL, FREAD, efbuf); 3698 } 3699 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3700 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3701 continue; 3702 #ifdef CAPABILITIES 3703 rights = *cap_rights(fdp, i); 3704 #else /* !CAPABILITIES */ 3705 rights = cap_no_rights; 3706 #endif 3707 /* 3708 * Create sysctl entry. It is OK to drop the filedesc 3709 * lock inside of export_file_to_sb() as we will 3710 * re-validate and re-evaluate its properties when the 3711 * loop continues. 3712 */ 3713 error = export_file_to_sb(fp, i, &rights, efbuf); 3714 if (error != 0 || efbuf->remainder == 0) 3715 break; 3716 } 3717 FILEDESC_SUNLOCK(fdp); 3718 fddrop(fdp); 3719 fail: 3720 free(efbuf, M_TEMP); 3721 return (error); 3722 } 3723 3724 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3725 3726 /* 3727 * Get per-process file descriptors for use by procstat(1), et al. 3728 */ 3729 static int 3730 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3731 { 3732 struct sbuf sb; 3733 struct proc *p; 3734 ssize_t maxlen; 3735 int error, error2, *name; 3736 3737 name = (int *)arg1; 3738 3739 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3740 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 3741 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3742 if (error != 0) { 3743 sbuf_delete(&sb); 3744 return (error); 3745 } 3746 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3747 error = kern_proc_filedesc_out(p, &sb, maxlen, 3748 KERN_FILEDESC_PACK_KINFO); 3749 error2 = sbuf_finish(&sb); 3750 sbuf_delete(&sb); 3751 return (error != 0 ? error : error2); 3752 } 3753 3754 #ifdef COMPAT_FREEBSD7 3755 #ifdef KINFO_OFILE_SIZE 3756 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 3757 #endif 3758 3759 static void 3760 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif) 3761 { 3762 3763 okif->kf_structsize = sizeof(*okif); 3764 okif->kf_type = kif->kf_type; 3765 okif->kf_fd = kif->kf_fd; 3766 okif->kf_ref_count = kif->kf_ref_count; 3767 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE | 3768 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK | 3769 KF_FLAG_DIRECT | KF_FLAG_HASLOCK); 3770 okif->kf_offset = kif->kf_offset; 3771 if (kif->kf_type == KF_TYPE_VNODE) 3772 okif->kf_vnode_type = kif->kf_un.kf_file.kf_file_type; 3773 else 3774 okif->kf_vnode_type = KF_VTYPE_VNON; 3775 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path)); 3776 if (kif->kf_type == KF_TYPE_SOCKET) { 3777 okif->kf_sock_domain = kif->kf_un.kf_sock.kf_sock_domain0; 3778 okif->kf_sock_type = kif->kf_un.kf_sock.kf_sock_type0; 3779 okif->kf_sock_protocol = kif->kf_un.kf_sock.kf_sock_protocol0; 3780 okif->kf_sa_local = kif->kf_un.kf_sock.kf_sa_local; 3781 okif->kf_sa_peer = kif->kf_un.kf_sock.kf_sa_peer; 3782 } else { 3783 okif->kf_sa_local.ss_family = AF_UNSPEC; 3784 okif->kf_sa_peer.ss_family = AF_UNSPEC; 3785 } 3786 } 3787 3788 static int 3789 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif, 3790 struct kinfo_ofile *okif, struct filedesc *fdp, struct sysctl_req *req) 3791 { 3792 int error; 3793 3794 vrefact(vp); 3795 FILEDESC_SUNLOCK(fdp); 3796 export_vnode_to_kinfo(vp, type, 0, kif, KERN_FILEDESC_PACK_KINFO); 3797 kinfo_to_okinfo(kif, okif); 3798 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 3799 FILEDESC_SLOCK(fdp); 3800 return (error); 3801 } 3802 3803 /* 3804 * Get per-process file descriptors for use by procstat(1), et al. 3805 */ 3806 static int 3807 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3808 { 3809 struct kinfo_ofile *okif; 3810 struct kinfo_file *kif; 3811 struct filedesc *fdp; 3812 int error, i, *name; 3813 struct file *fp; 3814 struct proc *p; 3815 3816 name = (int *)arg1; 3817 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3818 if (error != 0) 3819 return (error); 3820 fdp = fdhold(p); 3821 PROC_UNLOCK(p); 3822 if (fdp == NULL) 3823 return (ENOENT); 3824 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3825 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK); 3826 FILEDESC_SLOCK(fdp); 3827 if (fdp->fd_cdir != NULL) 3828 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3829 okif, fdp, req); 3830 if (fdp->fd_rdir != NULL) 3831 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3832 okif, fdp, req); 3833 if (fdp->fd_jdir != NULL) 3834 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3835 okif, fdp, req); 3836 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3837 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3838 continue; 3839 export_file_to_kinfo(fp, i, NULL, kif, fdp, 3840 KERN_FILEDESC_PACK_KINFO); 3841 FILEDESC_SUNLOCK(fdp); 3842 kinfo_to_okinfo(kif, okif); 3843 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 3844 FILEDESC_SLOCK(fdp); 3845 if (error) 3846 break; 3847 } 3848 FILEDESC_SUNLOCK(fdp); 3849 fddrop(fdp); 3850 free(kif, M_TEMP); 3851 free(okif, M_TEMP); 3852 return (0); 3853 } 3854 3855 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 3856 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 3857 "Process ofiledesc entries"); 3858 #endif /* COMPAT_FREEBSD7 */ 3859 3860 int 3861 vntype_to_kinfo(int vtype) 3862 { 3863 struct { 3864 int vtype; 3865 int kf_vtype; 3866 } vtypes_table[] = { 3867 { VBAD, KF_VTYPE_VBAD }, 3868 { VBLK, KF_VTYPE_VBLK }, 3869 { VCHR, KF_VTYPE_VCHR }, 3870 { VDIR, KF_VTYPE_VDIR }, 3871 { VFIFO, KF_VTYPE_VFIFO }, 3872 { VLNK, KF_VTYPE_VLNK }, 3873 { VNON, KF_VTYPE_VNON }, 3874 { VREG, KF_VTYPE_VREG }, 3875 { VSOCK, KF_VTYPE_VSOCK } 3876 }; 3877 unsigned int i; 3878 3879 /* 3880 * Perform vtype translation. 3881 */ 3882 for (i = 0; i < nitems(vtypes_table); i++) 3883 if (vtypes_table[i].vtype == vtype) 3884 return (vtypes_table[i].kf_vtype); 3885 3886 return (KF_VTYPE_UNKNOWN); 3887 } 3888 3889 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 3890 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 3891 "Process filedesc entries"); 3892 3893 /* 3894 * Store a process current working directory information to sbuf. 3895 * 3896 * Takes a locked proc as argument, and returns with the proc unlocked. 3897 */ 3898 int 3899 kern_proc_cwd_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3900 { 3901 struct filedesc *fdp; 3902 struct export_fd_buf *efbuf; 3903 int error; 3904 3905 PROC_LOCK_ASSERT(p, MA_OWNED); 3906 3907 fdp = fdhold(p); 3908 PROC_UNLOCK(p); 3909 if (fdp == NULL) 3910 return (EINVAL); 3911 3912 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3913 efbuf->fdp = fdp; 3914 efbuf->sb = sb; 3915 efbuf->remainder = maxlen; 3916 3917 FILEDESC_SLOCK(fdp); 3918 if (fdp->fd_cdir == NULL) 3919 error = EINVAL; 3920 else { 3921 vrefact(fdp->fd_cdir); 3922 error = export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD, 3923 FREAD, efbuf); 3924 } 3925 FILEDESC_SUNLOCK(fdp); 3926 fddrop(fdp); 3927 free(efbuf, M_TEMP); 3928 return (error); 3929 } 3930 3931 /* 3932 * Get per-process current working directory. 3933 */ 3934 static int 3935 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS) 3936 { 3937 struct sbuf sb; 3938 struct proc *p; 3939 ssize_t maxlen; 3940 int error, error2, *name; 3941 3942 name = (int *)arg1; 3943 3944 sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file), req); 3945 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 3946 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3947 if (error != 0) { 3948 sbuf_delete(&sb); 3949 return (error); 3950 } 3951 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3952 error = kern_proc_cwd_out(p, &sb, maxlen); 3953 error2 = sbuf_finish(&sb); 3954 sbuf_delete(&sb); 3955 return (error != 0 ? error : error2); 3956 } 3957 3958 static SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD|CTLFLAG_MPSAFE, 3959 sysctl_kern_proc_cwd, "Process current working directory"); 3960 3961 #ifdef DDB 3962 /* 3963 * For the purposes of debugging, generate a human-readable string for the 3964 * file type. 3965 */ 3966 static const char * 3967 file_type_to_name(short type) 3968 { 3969 3970 switch (type) { 3971 case 0: 3972 return ("zero"); 3973 case DTYPE_VNODE: 3974 return ("vnode"); 3975 case DTYPE_SOCKET: 3976 return ("socket"); 3977 case DTYPE_PIPE: 3978 return ("pipe"); 3979 case DTYPE_FIFO: 3980 return ("fifo"); 3981 case DTYPE_KQUEUE: 3982 return ("kqueue"); 3983 case DTYPE_CRYPTO: 3984 return ("crypto"); 3985 case DTYPE_MQUEUE: 3986 return ("mqueue"); 3987 case DTYPE_SHM: 3988 return ("shm"); 3989 case DTYPE_SEM: 3990 return ("ksem"); 3991 case DTYPE_PTS: 3992 return ("pts"); 3993 case DTYPE_DEV: 3994 return ("dev"); 3995 case DTYPE_PROCDESC: 3996 return ("proc"); 3997 case DTYPE_LINUXEFD: 3998 return ("levent"); 3999 case DTYPE_LINUXTFD: 4000 return ("ltimer"); 4001 default: 4002 return ("unkn"); 4003 } 4004 } 4005 4006 /* 4007 * For the purposes of debugging, identify a process (if any, perhaps one of 4008 * many) that references the passed file in its file descriptor array. Return 4009 * NULL if none. 4010 */ 4011 static struct proc * 4012 file_to_first_proc(struct file *fp) 4013 { 4014 struct filedesc *fdp; 4015 struct proc *p; 4016 int n; 4017 4018 FOREACH_PROC_IN_SYSTEM(p) { 4019 if (p->p_state == PRS_NEW) 4020 continue; 4021 fdp = p->p_fd; 4022 if (fdp == NULL) 4023 continue; 4024 for (n = 0; n <= fdp->fd_lastfile; n++) { 4025 if (fp == fdp->fd_ofiles[n].fde_file) 4026 return (p); 4027 } 4028 } 4029 return (NULL); 4030 } 4031 4032 static void 4033 db_print_file(struct file *fp, int header) 4034 { 4035 #define XPTRWIDTH ((int)howmany(sizeof(void *) * NBBY, 4)) 4036 struct proc *p; 4037 4038 if (header) 4039 db_printf("%*s %6s %*s %8s %4s %5s %6s %*s %5s %s\n", 4040 XPTRWIDTH, "File", "Type", XPTRWIDTH, "Data", "Flag", 4041 "GCFl", "Count", "MCount", XPTRWIDTH, "Vnode", "FPID", 4042 "FCmd"); 4043 p = file_to_first_proc(fp); 4044 db_printf("%*p %6s %*p %08x %04x %5d %6d %*p %5d %s\n", XPTRWIDTH, 4045 fp, file_type_to_name(fp->f_type), XPTRWIDTH, fp->f_data, 4046 fp->f_flag, 0, fp->f_count, 0, XPTRWIDTH, fp->f_vnode, 4047 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 4048 4049 #undef XPTRWIDTH 4050 } 4051 4052 DB_SHOW_COMMAND(file, db_show_file) 4053 { 4054 struct file *fp; 4055 4056 if (!have_addr) { 4057 db_printf("usage: show file <addr>\n"); 4058 return; 4059 } 4060 fp = (struct file *)addr; 4061 db_print_file(fp, 1); 4062 } 4063 4064 DB_SHOW_COMMAND(files, db_show_files) 4065 { 4066 struct filedesc *fdp; 4067 struct file *fp; 4068 struct proc *p; 4069 int header; 4070 int n; 4071 4072 header = 1; 4073 FOREACH_PROC_IN_SYSTEM(p) { 4074 if (p->p_state == PRS_NEW) 4075 continue; 4076 if ((fdp = p->p_fd) == NULL) 4077 continue; 4078 for (n = 0; n <= fdp->fd_lastfile; ++n) { 4079 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 4080 continue; 4081 db_print_file(fp, header); 4082 header = 0; 4083 } 4084 } 4085 } 4086 #endif 4087 4088 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 4089 &maxfilesperproc, 0, "Maximum files allowed open per process"); 4090 4091 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 4092 &maxfiles, 0, "Maximum number of files"); 4093 4094 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 4095 &openfiles, 0, "System-wide number of open files"); 4096 4097 /* ARGSUSED*/ 4098 static void 4099 filelistinit(void *dummy) 4100 { 4101 4102 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 4103 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 4104 filedesc0_zone = uma_zcreate("filedesc0", sizeof(struct filedesc0), 4105 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 4106 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 4107 } 4108 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 4109 4110 /*-------------------------------------------------------------------*/ 4111 4112 static int 4113 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 4114 int flags, struct thread *td) 4115 { 4116 4117 return (EBADF); 4118 } 4119 4120 static int 4121 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 4122 struct thread *td) 4123 { 4124 4125 return (EINVAL); 4126 } 4127 4128 static int 4129 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 4130 struct thread *td) 4131 { 4132 4133 return (EBADF); 4134 } 4135 4136 static int 4137 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 4138 struct thread *td) 4139 { 4140 4141 return (0); 4142 } 4143 4144 static int 4145 badfo_kqfilter(struct file *fp, struct knote *kn) 4146 { 4147 4148 return (EBADF); 4149 } 4150 4151 static int 4152 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 4153 struct thread *td) 4154 { 4155 4156 return (EBADF); 4157 } 4158 4159 static int 4160 badfo_close(struct file *fp, struct thread *td) 4161 { 4162 4163 return (0); 4164 } 4165 4166 static int 4167 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 4168 struct thread *td) 4169 { 4170 4171 return (EBADF); 4172 } 4173 4174 static int 4175 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4176 struct thread *td) 4177 { 4178 4179 return (EBADF); 4180 } 4181 4182 static int 4183 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4184 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4185 struct thread *td) 4186 { 4187 4188 return (EBADF); 4189 } 4190 4191 static int 4192 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp) 4193 { 4194 4195 return (0); 4196 } 4197 4198 struct fileops badfileops = { 4199 .fo_read = badfo_readwrite, 4200 .fo_write = badfo_readwrite, 4201 .fo_truncate = badfo_truncate, 4202 .fo_ioctl = badfo_ioctl, 4203 .fo_poll = badfo_poll, 4204 .fo_kqfilter = badfo_kqfilter, 4205 .fo_stat = badfo_stat, 4206 .fo_close = badfo_close, 4207 .fo_chmod = badfo_chmod, 4208 .fo_chown = badfo_chown, 4209 .fo_sendfile = badfo_sendfile, 4210 .fo_fill_kinfo = badfo_fill_kinfo, 4211 }; 4212 4213 int 4214 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred, 4215 int flags, struct thread *td) 4216 { 4217 4218 return (EOPNOTSUPP); 4219 } 4220 4221 int 4222 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 4223 struct thread *td) 4224 { 4225 4226 return (EINVAL); 4227 } 4228 4229 int 4230 invfo_ioctl(struct file *fp, u_long com, void *data, 4231 struct ucred *active_cred, struct thread *td) 4232 { 4233 4234 return (ENOTTY); 4235 } 4236 4237 int 4238 invfo_poll(struct file *fp, int events, struct ucred *active_cred, 4239 struct thread *td) 4240 { 4241 4242 return (poll_no_poll(events)); 4243 } 4244 4245 int 4246 invfo_kqfilter(struct file *fp, struct knote *kn) 4247 { 4248 4249 return (EINVAL); 4250 } 4251 4252 int 4253 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 4254 struct thread *td) 4255 { 4256 4257 return (EINVAL); 4258 } 4259 4260 int 4261 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4262 struct thread *td) 4263 { 4264 4265 return (EINVAL); 4266 } 4267 4268 int 4269 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4270 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4271 struct thread *td) 4272 { 4273 4274 return (EINVAL); 4275 } 4276 4277 /*-------------------------------------------------------------------*/ 4278 4279 /* 4280 * File Descriptor pseudo-device driver (/dev/fd/). 4281 * 4282 * Opening minor device N dup()s the file (if any) connected to file 4283 * descriptor N belonging to the calling process. Note that this driver 4284 * consists of only the ``open()'' routine, because all subsequent 4285 * references to this file will be direct to the other driver. 4286 * 4287 * XXX: we could give this one a cloning event handler if necessary. 4288 */ 4289 4290 /* ARGSUSED */ 4291 static int 4292 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 4293 { 4294 4295 /* 4296 * XXX Kludge: set curthread->td_dupfd to contain the value of the 4297 * the file descriptor being sought for duplication. The error 4298 * return ensures that the vnode for this device will be released 4299 * by vn_open. Open will detect this special error and take the 4300 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 4301 * will simply report the error. 4302 */ 4303 td->td_dupfd = dev2unit(dev); 4304 return (ENODEV); 4305 } 4306 4307 static struct cdevsw fildesc_cdevsw = { 4308 .d_version = D_VERSION, 4309 .d_open = fdopen, 4310 .d_name = "FD", 4311 }; 4312 4313 static void 4314 fildesc_drvinit(void *unused) 4315 { 4316 struct cdev *dev; 4317 4318 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4319 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4320 make_dev_alias(dev, "stdin"); 4321 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4322 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4323 make_dev_alias(dev, "stdout"); 4324 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4325 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4326 make_dev_alias(dev, "stderr"); 4327 } 4328 4329 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4330