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/smr.h> 73 #include <sys/stat.h> 74 #include <sys/sx.h> 75 #include <sys/syscallsubr.h> 76 #include <sys/sysctl.h> 77 #include <sys/sysproto.h> 78 #include <sys/unistd.h> 79 #include <sys/user.h> 80 #include <sys/vnode.h> 81 #ifdef KTRACE 82 #include <sys/ktrace.h> 83 #endif 84 85 #include <net/vnet.h> 86 87 #include <security/audit/audit.h> 88 89 #include <vm/uma.h> 90 #include <vm/vm.h> 91 92 #include <ddb/ddb.h> 93 94 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 95 static MALLOC_DEFINE(M_PWD, "pwd", "Descriptor table vnodes"); 96 static MALLOC_DEFINE(M_PWDDESC, "pwddesc", "Pwd descriptors"); 97 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 98 "file desc to leader structures"); 99 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 100 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 101 102 MALLOC_DECLARE(M_FADVISE); 103 104 static __read_mostly uma_zone_t file_zone; 105 static __read_mostly uma_zone_t filedesc0_zone; 106 __read_mostly uma_zone_t pwd_zone; 107 VFS_SMR_DECLARE; 108 109 static int closefp(struct filedesc *fdp, int fd, struct file *fp, 110 struct thread *td, bool holdleaders, bool audit); 111 static int fd_first_free(struct filedesc *fdp, int low, int size); 112 static void fdgrowtable(struct filedesc *fdp, int nfd); 113 static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 114 static void fdunused(struct filedesc *fdp, int fd); 115 static void fdused(struct filedesc *fdp, int fd); 116 static int getmaxfd(struct thread *td); 117 static u_long *filecaps_copy_prep(const struct filecaps *src); 118 static void filecaps_copy_finish(const struct filecaps *src, 119 struct filecaps *dst, u_long *ioctls); 120 static u_long *filecaps_free_prep(struct filecaps *fcaps); 121 static void filecaps_free_finish(u_long *ioctls); 122 123 static struct pwd *pwd_alloc(void); 124 125 /* 126 * Each process has: 127 * 128 * - An array of open file descriptors (fd_ofiles) 129 * - An array of file flags (fd_ofileflags) 130 * - A bitmap recording which descriptors are in use (fd_map) 131 * 132 * A process starts out with NDFILE descriptors. The value of NDFILE has 133 * been selected based the historical limit of 20 open files, and an 134 * assumption that the majority of processes, especially short-lived 135 * processes like shells, will never need more. 136 * 137 * If this initial allocation is exhausted, a larger descriptor table and 138 * map are allocated dynamically, and the pointers in the process's struct 139 * filedesc are updated to point to those. This is repeated every time 140 * the process runs out of file descriptors (provided it hasn't hit its 141 * resource limit). 142 * 143 * Since threads may hold references to individual descriptor table 144 * entries, the tables are never freed. Instead, they are placed on a 145 * linked list and freed only when the struct filedesc is released. 146 */ 147 #define NDFILE 20 148 #define NDSLOTSIZE sizeof(NDSLOTTYPE) 149 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 150 #define NDSLOT(x) ((x) / NDENTRIES) 151 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 152 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 153 154 /* 155 * SLIST entry used to keep track of ofiles which must be reclaimed when 156 * the process exits. 157 */ 158 struct freetable { 159 struct fdescenttbl *ft_table; 160 SLIST_ENTRY(freetable) ft_next; 161 }; 162 163 /* 164 * Initial allocation: a filedesc structure + the head of SLIST used to 165 * keep track of old ofiles + enough space for NDFILE descriptors. 166 */ 167 168 struct fdescenttbl0 { 169 int fdt_nfiles; 170 struct filedescent fdt_ofiles[NDFILE]; 171 }; 172 173 struct filedesc0 { 174 struct filedesc fd_fd; 175 SLIST_HEAD(, freetable) fd_free; 176 struct fdescenttbl0 fd_dfiles; 177 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 178 }; 179 180 /* 181 * Descriptor management. 182 */ 183 static int __exclusive_cache_line openfiles; /* actual number of open files */ 184 struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 185 void __read_mostly (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 186 187 /* 188 * If low >= size, just return low. Otherwise find the first zero bit in the 189 * given bitmap, starting at low and not exceeding size - 1. Return size if 190 * not found. 191 */ 192 static int 193 fd_first_free(struct filedesc *fdp, int low, int size) 194 { 195 NDSLOTTYPE *map = fdp->fd_map; 196 NDSLOTTYPE mask; 197 int off, maxoff; 198 199 if (low >= size) 200 return (low); 201 202 off = NDSLOT(low); 203 if (low % NDENTRIES) { 204 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 205 if ((mask &= ~map[off]) != 0UL) 206 return (off * NDENTRIES + ffsl(mask) - 1); 207 ++off; 208 } 209 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 210 if (map[off] != ~0UL) 211 return (off * NDENTRIES + ffsl(~map[off]) - 1); 212 return (size); 213 } 214 215 /* 216 * Find the last used fd. 217 * 218 * Call this variant if fdp can't be modified by anyone else (e.g, during exec). 219 * Otherwise use fdlastfile. 220 */ 221 int 222 fdlastfile_single(struct filedesc *fdp) 223 { 224 NDSLOTTYPE *map = fdp->fd_map; 225 int off, minoff; 226 227 off = NDSLOT(fdp->fd_nfiles - 1); 228 for (minoff = NDSLOT(0); off >= minoff; --off) 229 if (map[off] != 0) 230 return (off * NDENTRIES + flsl(map[off]) - 1); 231 return (-1); 232 } 233 234 int 235 fdlastfile(struct filedesc *fdp) 236 { 237 238 FILEDESC_LOCK_ASSERT(fdp); 239 return (fdlastfile_single(fdp)); 240 } 241 242 static int 243 fdisused(struct filedesc *fdp, int fd) 244 { 245 246 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 247 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 248 249 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 250 } 251 252 /* 253 * Mark a file descriptor as used. 254 */ 255 static void 256 fdused_init(struct filedesc *fdp, int fd) 257 { 258 259 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 260 261 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 262 } 263 264 static void 265 fdused(struct filedesc *fdp, int fd) 266 { 267 268 FILEDESC_XLOCK_ASSERT(fdp); 269 270 fdused_init(fdp, fd); 271 if (fd == fdp->fd_freefile) 272 fdp->fd_freefile++; 273 } 274 275 /* 276 * Mark a file descriptor as unused. 277 */ 278 static void 279 fdunused(struct filedesc *fdp, int fd) 280 { 281 282 FILEDESC_XLOCK_ASSERT(fdp); 283 284 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 285 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 286 ("fd=%d is still in use", fd)); 287 288 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 289 if (fd < fdp->fd_freefile) 290 fdp->fd_freefile = fd; 291 } 292 293 /* 294 * Free a file descriptor. 295 * 296 * Avoid some work if fdp is about to be destroyed. 297 */ 298 static inline void 299 fdefree_last(struct filedescent *fde) 300 { 301 302 filecaps_free(&fde->fde_caps); 303 } 304 305 static inline void 306 fdfree(struct filedesc *fdp, int fd) 307 { 308 struct filedescent *fde; 309 310 FILEDESC_XLOCK_ASSERT(fdp); 311 fde = &fdp->fd_ofiles[fd]; 312 #ifdef CAPABILITIES 313 seqc_write_begin(&fde->fde_seqc); 314 #endif 315 fde->fde_file = NULL; 316 #ifdef CAPABILITIES 317 seqc_write_end(&fde->fde_seqc); 318 #endif 319 fdefree_last(fde); 320 fdunused(fdp, fd); 321 } 322 323 /* 324 * System calls on descriptors. 325 */ 326 #ifndef _SYS_SYSPROTO_H_ 327 struct getdtablesize_args { 328 int dummy; 329 }; 330 #endif 331 /* ARGSUSED */ 332 int 333 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 334 { 335 #ifdef RACCT 336 uint64_t lim; 337 #endif 338 339 td->td_retval[0] = getmaxfd(td); 340 #ifdef RACCT 341 PROC_LOCK(td->td_proc); 342 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 343 PROC_UNLOCK(td->td_proc); 344 if (lim < td->td_retval[0]) 345 td->td_retval[0] = lim; 346 #endif 347 return (0); 348 } 349 350 /* 351 * Duplicate a file descriptor to a particular value. 352 * 353 * Note: keep in mind that a potential race condition exists when closing 354 * descriptors from a shared descriptor table (via rfork). 355 */ 356 #ifndef _SYS_SYSPROTO_H_ 357 struct dup2_args { 358 u_int from; 359 u_int to; 360 }; 361 #endif 362 /* ARGSUSED */ 363 int 364 sys_dup2(struct thread *td, struct dup2_args *uap) 365 { 366 367 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to)); 368 } 369 370 /* 371 * Duplicate a file descriptor. 372 */ 373 #ifndef _SYS_SYSPROTO_H_ 374 struct dup_args { 375 u_int fd; 376 }; 377 #endif 378 /* ARGSUSED */ 379 int 380 sys_dup(struct thread *td, struct dup_args *uap) 381 { 382 383 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0)); 384 } 385 386 /* 387 * The file control system call. 388 */ 389 #ifndef _SYS_SYSPROTO_H_ 390 struct fcntl_args { 391 int fd; 392 int cmd; 393 long arg; 394 }; 395 #endif 396 /* ARGSUSED */ 397 int 398 sys_fcntl(struct thread *td, struct fcntl_args *uap) 399 { 400 401 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg)); 402 } 403 404 int 405 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg) 406 { 407 struct flock fl; 408 struct __oflock ofl; 409 intptr_t arg1; 410 int error, newcmd; 411 412 error = 0; 413 newcmd = cmd; 414 switch (cmd) { 415 case F_OGETLK: 416 case F_OSETLK: 417 case F_OSETLKW: 418 /* 419 * Convert old flock structure to new. 420 */ 421 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl)); 422 fl.l_start = ofl.l_start; 423 fl.l_len = ofl.l_len; 424 fl.l_pid = ofl.l_pid; 425 fl.l_type = ofl.l_type; 426 fl.l_whence = ofl.l_whence; 427 fl.l_sysid = 0; 428 429 switch (cmd) { 430 case F_OGETLK: 431 newcmd = F_GETLK; 432 break; 433 case F_OSETLK: 434 newcmd = F_SETLK; 435 break; 436 case F_OSETLKW: 437 newcmd = F_SETLKW; 438 break; 439 } 440 arg1 = (intptr_t)&fl; 441 break; 442 case F_GETLK: 443 case F_SETLK: 444 case F_SETLKW: 445 case F_SETLK_REMOTE: 446 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl)); 447 arg1 = (intptr_t)&fl; 448 break; 449 default: 450 arg1 = arg; 451 break; 452 } 453 if (error) 454 return (error); 455 error = kern_fcntl(td, fd, newcmd, arg1); 456 if (error) 457 return (error); 458 if (cmd == F_OGETLK) { 459 ofl.l_start = fl.l_start; 460 ofl.l_len = fl.l_len; 461 ofl.l_pid = fl.l_pid; 462 ofl.l_type = fl.l_type; 463 ofl.l_whence = fl.l_whence; 464 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl)); 465 } else if (cmd == F_GETLK) { 466 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl)); 467 } 468 return (error); 469 } 470 471 int 472 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 473 { 474 struct filedesc *fdp; 475 struct flock *flp; 476 struct file *fp, *fp2; 477 struct filedescent *fde; 478 struct proc *p; 479 struct vnode *vp; 480 struct mount *mp; 481 int error, flg, seals, tmp; 482 uint64_t bsize; 483 off_t foffset; 484 485 error = 0; 486 flg = F_POSIX; 487 p = td->td_proc; 488 fdp = p->p_fd; 489 490 AUDIT_ARG_FD(cmd); 491 AUDIT_ARG_CMD(cmd); 492 switch (cmd) { 493 case F_DUPFD: 494 tmp = arg; 495 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp); 496 break; 497 498 case F_DUPFD_CLOEXEC: 499 tmp = arg; 500 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp); 501 break; 502 503 case F_DUP2FD: 504 tmp = arg; 505 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp); 506 break; 507 508 case F_DUP2FD_CLOEXEC: 509 tmp = arg; 510 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp); 511 break; 512 513 case F_GETFD: 514 error = EBADF; 515 FILEDESC_SLOCK(fdp); 516 fde = fdeget_locked(fdp, fd); 517 if (fde != NULL) { 518 td->td_retval[0] = 519 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 520 error = 0; 521 } 522 FILEDESC_SUNLOCK(fdp); 523 break; 524 525 case F_SETFD: 526 error = EBADF; 527 FILEDESC_XLOCK(fdp); 528 fde = fdeget_locked(fdp, fd); 529 if (fde != NULL) { 530 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 531 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 532 error = 0; 533 } 534 FILEDESC_XUNLOCK(fdp); 535 break; 536 537 case F_GETFL: 538 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETFL, &fp); 539 if (error != 0) 540 break; 541 td->td_retval[0] = OFLAGS(fp->f_flag); 542 fdrop(fp, td); 543 break; 544 545 case F_SETFL: 546 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETFL, &fp); 547 if (error != 0) 548 break; 549 do { 550 tmp = flg = fp->f_flag; 551 tmp &= ~FCNTLFLAGS; 552 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 553 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 554 tmp = fp->f_flag & FNONBLOCK; 555 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 556 if (error != 0) { 557 fdrop(fp, td); 558 break; 559 } 560 tmp = fp->f_flag & FASYNC; 561 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 562 if (error == 0) { 563 fdrop(fp, td); 564 break; 565 } 566 atomic_clear_int(&fp->f_flag, FNONBLOCK); 567 tmp = 0; 568 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 569 fdrop(fp, td); 570 break; 571 572 case F_GETOWN: 573 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETOWN, &fp); 574 if (error != 0) 575 break; 576 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 577 if (error == 0) 578 td->td_retval[0] = tmp; 579 fdrop(fp, td); 580 break; 581 582 case F_SETOWN: 583 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETOWN, &fp); 584 if (error != 0) 585 break; 586 tmp = arg; 587 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 588 fdrop(fp, td); 589 break; 590 591 case F_SETLK_REMOTE: 592 error = priv_check(td, PRIV_NFS_LOCKD); 593 if (error != 0) 594 return (error); 595 flg = F_REMOTE; 596 goto do_setlk; 597 598 case F_SETLKW: 599 flg |= F_WAIT; 600 /* FALLTHROUGH F_SETLK */ 601 602 case F_SETLK: 603 do_setlk: 604 flp = (struct flock *)arg; 605 if ((flg & F_REMOTE) != 0 && flp->l_sysid == 0) { 606 error = EINVAL; 607 break; 608 } 609 610 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp); 611 if (error != 0) 612 break; 613 if (fp->f_type != DTYPE_VNODE) { 614 error = EBADF; 615 fdrop(fp, td); 616 break; 617 } 618 619 if (flp->l_whence == SEEK_CUR) { 620 foffset = foffset_get(fp); 621 if (foffset < 0 || 622 (flp->l_start > 0 && 623 foffset > OFF_MAX - flp->l_start)) { 624 error = EOVERFLOW; 625 fdrop(fp, td); 626 break; 627 } 628 flp->l_start += foffset; 629 } 630 631 vp = fp->f_vnode; 632 switch (flp->l_type) { 633 case F_RDLCK: 634 if ((fp->f_flag & FREAD) == 0) { 635 error = EBADF; 636 break; 637 } 638 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { 639 PROC_LOCK(p->p_leader); 640 p->p_leader->p_flag |= P_ADVLOCK; 641 PROC_UNLOCK(p->p_leader); 642 } 643 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 644 flp, flg); 645 break; 646 case F_WRLCK: 647 if ((fp->f_flag & FWRITE) == 0) { 648 error = EBADF; 649 break; 650 } 651 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { 652 PROC_LOCK(p->p_leader); 653 p->p_leader->p_flag |= P_ADVLOCK; 654 PROC_UNLOCK(p->p_leader); 655 } 656 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 657 flp, flg); 658 break; 659 case F_UNLCK: 660 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 661 flp, flg); 662 break; 663 case F_UNLCKSYS: 664 if (flg != F_REMOTE) { 665 error = EINVAL; 666 break; 667 } 668 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 669 F_UNLCKSYS, flp, flg); 670 break; 671 default: 672 error = EINVAL; 673 break; 674 } 675 if (error != 0 || flp->l_type == F_UNLCK || 676 flp->l_type == F_UNLCKSYS) { 677 fdrop(fp, td); 678 break; 679 } 680 681 /* 682 * Check for a race with close. 683 * 684 * The vnode is now advisory locked (or unlocked, but this case 685 * is not really important) as the caller requested. 686 * We had to drop the filedesc lock, so we need to recheck if 687 * the descriptor is still valid, because if it was closed 688 * in the meantime we need to remove advisory lock from the 689 * vnode - close on any descriptor leading to an advisory 690 * locked vnode, removes that lock. 691 * We will return 0 on purpose in that case, as the result of 692 * successful advisory lock might have been externally visible 693 * already. This is fine - effectively we pretend to the caller 694 * that the closing thread was a bit slower and that the 695 * advisory lock succeeded before the close. 696 */ 697 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp2); 698 if (error != 0) { 699 fdrop(fp, td); 700 break; 701 } 702 if (fp != fp2) { 703 flp->l_whence = SEEK_SET; 704 flp->l_start = 0; 705 flp->l_len = 0; 706 flp->l_type = F_UNLCK; 707 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 708 F_UNLCK, flp, F_POSIX); 709 } 710 fdrop(fp, td); 711 fdrop(fp2, td); 712 break; 713 714 case F_GETLK: 715 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp); 716 if (error != 0) 717 break; 718 if (fp->f_type != DTYPE_VNODE) { 719 error = EBADF; 720 fdrop(fp, td); 721 break; 722 } 723 flp = (struct flock *)arg; 724 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 725 flp->l_type != F_UNLCK) { 726 error = EINVAL; 727 fdrop(fp, td); 728 break; 729 } 730 if (flp->l_whence == SEEK_CUR) { 731 foffset = foffset_get(fp); 732 if ((flp->l_start > 0 && 733 foffset > OFF_MAX - flp->l_start) || 734 (flp->l_start < 0 && 735 foffset < OFF_MIN - flp->l_start)) { 736 error = EOVERFLOW; 737 fdrop(fp, td); 738 break; 739 } 740 flp->l_start += foffset; 741 } 742 vp = fp->f_vnode; 743 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 744 F_POSIX); 745 fdrop(fp, td); 746 break; 747 748 case F_ADD_SEALS: 749 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp); 750 if (error != 0) 751 break; 752 error = fo_add_seals(fp, arg); 753 fdrop(fp, td); 754 break; 755 756 case F_GET_SEALS: 757 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp); 758 if (error != 0) 759 break; 760 if (fo_get_seals(fp, &seals) == 0) 761 td->td_retval[0] = seals; 762 else 763 error = EINVAL; 764 fdrop(fp, td); 765 break; 766 767 case F_RDAHEAD: 768 arg = arg ? 128 * 1024: 0; 769 /* FALLTHROUGH */ 770 case F_READAHEAD: 771 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp); 772 if (error != 0) 773 break; 774 if (fp->f_type != DTYPE_VNODE) { 775 fdrop(fp, td); 776 error = EBADF; 777 break; 778 } 779 vp = fp->f_vnode; 780 if (vp->v_type != VREG) { 781 fdrop(fp, td); 782 error = ENOTTY; 783 break; 784 } 785 786 /* 787 * Exclusive lock synchronizes against f_seqcount reads and 788 * writes in sequential_heuristic(). 789 */ 790 error = vn_lock(vp, LK_EXCLUSIVE); 791 if (error != 0) { 792 fdrop(fp, td); 793 break; 794 } 795 if (arg >= 0) { 796 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 797 arg = MIN(arg, INT_MAX - bsize + 1); 798 fp->f_seqcount[UIO_READ] = MIN(IO_SEQMAX, 799 (arg + bsize - 1) / bsize); 800 atomic_set_int(&fp->f_flag, FRDAHEAD); 801 } else { 802 atomic_clear_int(&fp->f_flag, FRDAHEAD); 803 } 804 VOP_UNLOCK(vp); 805 fdrop(fp, td); 806 break; 807 808 case F_ISUNIONSTACK: 809 /* 810 * Check if the vnode is part of a union stack (either the 811 * "union" flag from mount(2) or unionfs). 812 * 813 * Prior to introduction of this op libc's readdir would call 814 * fstatfs(2), in effect unnecessarily copying kilobytes of 815 * data just to check fs name and a mount flag. 816 * 817 * Fixing the code to handle everything in the kernel instead 818 * is a non-trivial endeavor and has low priority, thus this 819 * horrible kludge facilitates the current behavior in a much 820 * cheaper manner until someone(tm) sorts this out. 821 */ 822 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp); 823 if (error != 0) 824 break; 825 if (fp->f_type != DTYPE_VNODE) { 826 fdrop(fp, td); 827 error = EBADF; 828 break; 829 } 830 vp = fp->f_vnode; 831 /* 832 * Since we don't prevent dooming the vnode even non-null mp 833 * found can become immediately stale. This is tolerable since 834 * mount points are type-stable (providing safe memory access) 835 * and any vfs op on this vnode going forward will return an 836 * error (meaning return value in this case is meaningless). 837 */ 838 mp = atomic_load_ptr(&vp->v_mount); 839 if (__predict_false(mp == NULL)) { 840 fdrop(fp, td); 841 error = EBADF; 842 break; 843 } 844 td->td_retval[0] = 0; 845 if (mp->mnt_kern_flag & MNTK_UNIONFS || 846 mp->mnt_flag & MNT_UNION) 847 td->td_retval[0] = 1; 848 fdrop(fp, td); 849 break; 850 851 default: 852 error = EINVAL; 853 break; 854 } 855 return (error); 856 } 857 858 static int 859 getmaxfd(struct thread *td) 860 { 861 862 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc)); 863 } 864 865 /* 866 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 867 */ 868 int 869 kern_dup(struct thread *td, u_int mode, int flags, int old, int new) 870 { 871 struct filedesc *fdp; 872 struct filedescent *oldfde, *newfde; 873 struct proc *p; 874 struct file *delfp, *oldfp; 875 u_long *oioctls, *nioctls; 876 int error, maxfd; 877 878 p = td->td_proc; 879 fdp = p->p_fd; 880 oioctls = NULL; 881 882 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0); 883 MPASS(mode < FDDUP_LASTMODE); 884 885 AUDIT_ARG_FD(old); 886 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */ 887 888 /* 889 * Verify we have a valid descriptor to dup from and possibly to 890 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 891 * return EINVAL when the new descriptor is out of bounds. 892 */ 893 if (old < 0) 894 return (EBADF); 895 if (new < 0) 896 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 897 maxfd = getmaxfd(td); 898 if (new >= maxfd) 899 return (mode == FDDUP_FCNTL ? EINVAL : EBADF); 900 901 error = EBADF; 902 FILEDESC_XLOCK(fdp); 903 if (fget_locked(fdp, old) == NULL) 904 goto unlock; 905 if ((mode == FDDUP_FIXED || mode == FDDUP_MUSTREPLACE) && old == new) { 906 td->td_retval[0] = new; 907 if (flags & FDDUP_FLAG_CLOEXEC) 908 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 909 error = 0; 910 goto unlock; 911 } 912 913 oldfde = &fdp->fd_ofiles[old]; 914 oldfp = oldfde->fde_file; 915 if (!fhold(oldfp)) 916 goto unlock; 917 918 /* 919 * If the caller specified a file descriptor, make sure the file 920 * table is large enough to hold it, and grab it. Otherwise, just 921 * allocate a new descriptor the usual way. 922 */ 923 switch (mode) { 924 case FDDUP_NORMAL: 925 case FDDUP_FCNTL: 926 if ((error = fdalloc(td, new, &new)) != 0) { 927 fdrop(oldfp, td); 928 goto unlock; 929 } 930 break; 931 case FDDUP_MUSTREPLACE: 932 /* Target file descriptor must exist. */ 933 if (fget_locked(fdp, new) == NULL) { 934 fdrop(oldfp, td); 935 goto unlock; 936 } 937 break; 938 case FDDUP_FIXED: 939 if (new >= fdp->fd_nfiles) { 940 /* 941 * The resource limits are here instead of e.g. 942 * fdalloc(), because the file descriptor table may be 943 * shared between processes, so we can't really use 944 * racct_add()/racct_sub(). Instead of counting the 945 * number of actually allocated descriptors, just put 946 * the limit on the size of the file descriptor table. 947 */ 948 #ifdef RACCT 949 if (RACCT_ENABLED()) { 950 error = racct_set_unlocked(p, RACCT_NOFILE, new + 1); 951 if (error != 0) { 952 error = EMFILE; 953 fdrop(oldfp, td); 954 goto unlock; 955 } 956 } 957 #endif 958 fdgrowtable_exp(fdp, new + 1); 959 } 960 if (!fdisused(fdp, new)) 961 fdused(fdp, new); 962 break; 963 default: 964 KASSERT(0, ("%s unsupported mode %d", __func__, mode)); 965 } 966 967 KASSERT(old != new, ("new fd is same as old")); 968 969 /* Refetch oldfde because the table may have grown and old one freed. */ 970 oldfde = &fdp->fd_ofiles[old]; 971 KASSERT(oldfp == oldfde->fde_file, 972 ("fdt_ofiles shift from growth observed at fd %d", 973 old)); 974 975 newfde = &fdp->fd_ofiles[new]; 976 delfp = newfde->fde_file; 977 978 nioctls = filecaps_copy_prep(&oldfde->fde_caps); 979 980 /* 981 * Duplicate the source descriptor. 982 */ 983 #ifdef CAPABILITIES 984 seqc_write_begin(&newfde->fde_seqc); 985 #endif 986 oioctls = filecaps_free_prep(&newfde->fde_caps); 987 memcpy(newfde, oldfde, fde_change_size); 988 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps, 989 nioctls); 990 if ((flags & FDDUP_FLAG_CLOEXEC) != 0) 991 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 992 else 993 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 994 #ifdef CAPABILITIES 995 seqc_write_end(&newfde->fde_seqc); 996 #endif 997 td->td_retval[0] = new; 998 999 error = 0; 1000 1001 if (delfp != NULL) { 1002 (void) closefp(fdp, new, delfp, td, true, false); 1003 FILEDESC_UNLOCK_ASSERT(fdp); 1004 } else { 1005 unlock: 1006 FILEDESC_XUNLOCK(fdp); 1007 } 1008 1009 filecaps_free_finish(oioctls); 1010 return (error); 1011 } 1012 1013 static void 1014 sigiofree(struct sigio *sigio) 1015 { 1016 crfree(sigio->sio_ucred); 1017 free(sigio, M_SIGIO); 1018 } 1019 1020 static struct sigio * 1021 funsetown_locked(struct sigio *sigio) 1022 { 1023 struct proc *p; 1024 struct pgrp *pg; 1025 1026 SIGIO_ASSERT_LOCKED(); 1027 1028 if (sigio == NULL) 1029 return (NULL); 1030 *(sigio->sio_myref) = NULL; 1031 if (sigio->sio_pgid < 0) { 1032 pg = sigio->sio_pgrp; 1033 PGRP_LOCK(pg); 1034 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 1035 sigio, sio_pgsigio); 1036 PGRP_UNLOCK(pg); 1037 } else { 1038 p = sigio->sio_proc; 1039 PROC_LOCK(p); 1040 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 1041 sigio, sio_pgsigio); 1042 PROC_UNLOCK(p); 1043 } 1044 return (sigio); 1045 } 1046 1047 /* 1048 * If sigio is on the list associated with a process or process group, 1049 * disable signalling from the device, remove sigio from the list and 1050 * free sigio. 1051 */ 1052 void 1053 funsetown(struct sigio **sigiop) 1054 { 1055 struct sigio *sigio; 1056 1057 /* Racy check, consumers must provide synchronization. */ 1058 if (*sigiop == NULL) 1059 return; 1060 1061 SIGIO_LOCK(); 1062 sigio = funsetown_locked(*sigiop); 1063 SIGIO_UNLOCK(); 1064 if (sigio != NULL) 1065 sigiofree(sigio); 1066 } 1067 1068 /* 1069 * Free a list of sigio structures. The caller must ensure that new sigio 1070 * structures cannot be added after this point. For process groups this is 1071 * guaranteed using the proctree lock; for processes, the P_WEXIT flag serves 1072 * as an interlock. 1073 */ 1074 void 1075 funsetownlst(struct sigiolst *sigiolst) 1076 { 1077 struct proc *p; 1078 struct pgrp *pg; 1079 struct sigio *sigio, *tmp; 1080 1081 /* Racy check. */ 1082 sigio = SLIST_FIRST(sigiolst); 1083 if (sigio == NULL) 1084 return; 1085 1086 p = NULL; 1087 pg = NULL; 1088 1089 SIGIO_LOCK(); 1090 sigio = SLIST_FIRST(sigiolst); 1091 if (sigio == NULL) { 1092 SIGIO_UNLOCK(); 1093 return; 1094 } 1095 1096 /* 1097 * Every entry of the list should belong to a single proc or pgrp. 1098 */ 1099 if (sigio->sio_pgid < 0) { 1100 pg = sigio->sio_pgrp; 1101 sx_assert(&proctree_lock, SX_XLOCKED); 1102 PGRP_LOCK(pg); 1103 } else /* if (sigio->sio_pgid > 0) */ { 1104 p = sigio->sio_proc; 1105 PROC_LOCK(p); 1106 KASSERT((p->p_flag & P_WEXIT) != 0, 1107 ("%s: process %p is not exiting", __func__, p)); 1108 } 1109 1110 SLIST_FOREACH(sigio, sigiolst, sio_pgsigio) { 1111 *sigio->sio_myref = NULL; 1112 if (pg != NULL) { 1113 KASSERT(sigio->sio_pgid < 0, 1114 ("Proc sigio in pgrp sigio list")); 1115 KASSERT(sigio->sio_pgrp == pg, 1116 ("Bogus pgrp in sigio list")); 1117 } else /* if (p != NULL) */ { 1118 KASSERT(sigio->sio_pgid > 0, 1119 ("Pgrp sigio in proc sigio list")); 1120 KASSERT(sigio->sio_proc == p, 1121 ("Bogus proc in sigio list")); 1122 } 1123 } 1124 1125 if (pg != NULL) 1126 PGRP_UNLOCK(pg); 1127 else 1128 PROC_UNLOCK(p); 1129 SIGIO_UNLOCK(); 1130 1131 SLIST_FOREACH_SAFE(sigio, sigiolst, sio_pgsigio, tmp) 1132 sigiofree(sigio); 1133 } 1134 1135 /* 1136 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1137 * 1138 * After permission checking, add a sigio structure to the sigio list for 1139 * the process or process group. 1140 */ 1141 int 1142 fsetown(pid_t pgid, struct sigio **sigiop) 1143 { 1144 struct proc *proc; 1145 struct pgrp *pgrp; 1146 struct sigio *osigio, *sigio; 1147 int ret; 1148 1149 if (pgid == 0) { 1150 funsetown(sigiop); 1151 return (0); 1152 } 1153 1154 ret = 0; 1155 1156 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1157 sigio->sio_pgid = pgid; 1158 sigio->sio_ucred = crhold(curthread->td_ucred); 1159 sigio->sio_myref = sigiop; 1160 1161 sx_slock(&proctree_lock); 1162 SIGIO_LOCK(); 1163 osigio = funsetown_locked(*sigiop); 1164 if (pgid > 0) { 1165 proc = pfind(pgid); 1166 if (proc == NULL) { 1167 ret = ESRCH; 1168 goto fail; 1169 } 1170 1171 /* 1172 * Policy - Don't allow a process to FSETOWN a process 1173 * in another session. 1174 * 1175 * Remove this test to allow maximum flexibility or 1176 * restrict FSETOWN to the current process or process 1177 * group for maximum safety. 1178 */ 1179 if (proc->p_session != curthread->td_proc->p_session) { 1180 PROC_UNLOCK(proc); 1181 ret = EPERM; 1182 goto fail; 1183 } 1184 1185 sigio->sio_proc = proc; 1186 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1187 PROC_UNLOCK(proc); 1188 } else /* if (pgid < 0) */ { 1189 pgrp = pgfind(-pgid); 1190 if (pgrp == NULL) { 1191 ret = ESRCH; 1192 goto fail; 1193 } 1194 1195 /* 1196 * Policy - Don't allow a process to FSETOWN a process 1197 * in another session. 1198 * 1199 * Remove this test to allow maximum flexibility or 1200 * restrict FSETOWN to the current process or process 1201 * group for maximum safety. 1202 */ 1203 if (pgrp->pg_session != curthread->td_proc->p_session) { 1204 PGRP_UNLOCK(pgrp); 1205 ret = EPERM; 1206 goto fail; 1207 } 1208 1209 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1210 sigio->sio_pgrp = pgrp; 1211 PGRP_UNLOCK(pgrp); 1212 } 1213 sx_sunlock(&proctree_lock); 1214 *sigiop = sigio; 1215 SIGIO_UNLOCK(); 1216 if (osigio != NULL) 1217 sigiofree(osigio); 1218 return (0); 1219 1220 fail: 1221 SIGIO_UNLOCK(); 1222 sx_sunlock(&proctree_lock); 1223 sigiofree(sigio); 1224 if (osigio != NULL) 1225 sigiofree(osigio); 1226 return (ret); 1227 } 1228 1229 /* 1230 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1231 */ 1232 pid_t 1233 fgetown(struct sigio **sigiop) 1234 { 1235 pid_t pgid; 1236 1237 SIGIO_LOCK(); 1238 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1239 SIGIO_UNLOCK(); 1240 return (pgid); 1241 } 1242 1243 static int 1244 closefp_impl(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1245 bool audit) 1246 { 1247 int error; 1248 1249 FILEDESC_XLOCK_ASSERT(fdp); 1250 1251 /* 1252 * We now hold the fp reference that used to be owned by the 1253 * descriptor array. We have to unlock the FILEDESC *AFTER* 1254 * knote_fdclose to prevent a race of the fd getting opened, a knote 1255 * added, and deleteing a knote for the new fd. 1256 */ 1257 if (__predict_false(!TAILQ_EMPTY(&fdp->fd_kqlist))) 1258 knote_fdclose(td, fd); 1259 1260 /* 1261 * We need to notify mqueue if the object is of type mqueue. 1262 */ 1263 if (__predict_false(fp->f_type == DTYPE_MQUEUE)) 1264 mq_fdclose(td, fd, fp); 1265 FILEDESC_XUNLOCK(fdp); 1266 1267 #ifdef AUDIT 1268 if (AUDITING_TD(td) && audit) 1269 audit_sysclose(td, fd, fp); 1270 #endif 1271 error = closef(fp, td); 1272 1273 /* 1274 * All paths leading up to closefp() will have already removed or 1275 * replaced the fd in the filedesc table, so a restart would not 1276 * operate on the same file. 1277 */ 1278 if (error == ERESTART) 1279 error = EINTR; 1280 1281 return (error); 1282 } 1283 1284 static int 1285 closefp_hl(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1286 bool holdleaders, bool audit) 1287 { 1288 int error; 1289 1290 FILEDESC_XLOCK_ASSERT(fdp); 1291 1292 if (holdleaders) { 1293 if (td->td_proc->p_fdtol != NULL) { 1294 /* 1295 * Ask fdfree() to sleep to ensure that all relevant 1296 * process leaders can be traversed in closef(). 1297 */ 1298 fdp->fd_holdleaderscount++; 1299 } else { 1300 holdleaders = false; 1301 } 1302 } 1303 1304 error = closefp_impl(fdp, fd, fp, td, audit); 1305 if (holdleaders) { 1306 FILEDESC_XLOCK(fdp); 1307 fdp->fd_holdleaderscount--; 1308 if (fdp->fd_holdleaderscount == 0 && 1309 fdp->fd_holdleaderswakeup != 0) { 1310 fdp->fd_holdleaderswakeup = 0; 1311 wakeup(&fdp->fd_holdleaderscount); 1312 } 1313 FILEDESC_XUNLOCK(fdp); 1314 } 1315 return (error); 1316 } 1317 1318 static int 1319 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1320 bool holdleaders, bool audit) 1321 { 1322 1323 FILEDESC_XLOCK_ASSERT(fdp); 1324 1325 if (__predict_false(td->td_proc->p_fdtol != NULL)) { 1326 return (closefp_hl(fdp, fd, fp, td, holdleaders, audit)); 1327 } else { 1328 return (closefp_impl(fdp, fd, fp, td, audit)); 1329 } 1330 } 1331 1332 /* 1333 * Close a file descriptor. 1334 */ 1335 #ifndef _SYS_SYSPROTO_H_ 1336 struct close_args { 1337 int fd; 1338 }; 1339 #endif 1340 /* ARGSUSED */ 1341 int 1342 sys_close(struct thread *td, struct close_args *uap) 1343 { 1344 1345 return (kern_close(td, uap->fd)); 1346 } 1347 1348 int 1349 kern_close(struct thread *td, int fd) 1350 { 1351 struct filedesc *fdp; 1352 struct file *fp; 1353 1354 fdp = td->td_proc->p_fd; 1355 1356 FILEDESC_XLOCK(fdp); 1357 if ((fp = fget_locked(fdp, fd)) == NULL) { 1358 FILEDESC_XUNLOCK(fdp); 1359 return (EBADF); 1360 } 1361 fdfree(fdp, fd); 1362 1363 /* closefp() drops the FILEDESC lock for us. */ 1364 return (closefp(fdp, fd, fp, td, true, true)); 1365 } 1366 1367 int 1368 kern_close_range(struct thread *td, u_int lowfd, u_int highfd) 1369 { 1370 struct filedesc *fdp; 1371 const struct fdescenttbl *fdt; 1372 struct file *fp; 1373 int fd; 1374 1375 /* 1376 * Check this prior to clamping; closefrom(3) with only fd 0, 1, and 2 1377 * open should not be a usage error. From a close_range() perspective, 1378 * close_range(3, ~0U, 0) in the same scenario should also likely not 1379 * be a usage error as all fd above 3 are in-fact already closed. 1380 */ 1381 if (highfd < lowfd) { 1382 return (EINVAL); 1383 } 1384 1385 fdp = td->td_proc->p_fd; 1386 FILEDESC_XLOCK(fdp); 1387 fdt = atomic_load_ptr(&fdp->fd_files); 1388 highfd = MIN(highfd, fdt->fdt_nfiles - 1); 1389 fd = lowfd; 1390 if (__predict_false(fd > highfd)) { 1391 goto out_locked; 1392 } 1393 for (;;) { 1394 fp = fdt->fdt_ofiles[fd].fde_file; 1395 if (fp == NULL) { 1396 if (fd == highfd) 1397 goto out_locked; 1398 } else { 1399 fdfree(fdp, fd); 1400 (void) closefp(fdp, fd, fp, td, true, true); 1401 if (fd == highfd) 1402 goto out_unlocked; 1403 FILEDESC_XLOCK(fdp); 1404 fdt = atomic_load_ptr(&fdp->fd_files); 1405 } 1406 fd++; 1407 } 1408 out_locked: 1409 FILEDESC_XUNLOCK(fdp); 1410 out_unlocked: 1411 return (0); 1412 } 1413 1414 #ifndef _SYS_SYSPROTO_H_ 1415 struct close_range_args { 1416 u_int lowfd; 1417 u_int highfd; 1418 int flags; 1419 }; 1420 #endif 1421 int 1422 sys_close_range(struct thread *td, struct close_range_args *uap) 1423 { 1424 1425 /* No flags currently defined */ 1426 if (uap->flags != 0) 1427 return (EINVAL); 1428 return (kern_close_range(td, uap->lowfd, uap->highfd)); 1429 } 1430 1431 #ifdef COMPAT_FREEBSD12 1432 /* 1433 * Close open file descriptors. 1434 */ 1435 #ifndef _SYS_SYSPROTO_H_ 1436 struct freebsd12_closefrom_args { 1437 int lowfd; 1438 }; 1439 #endif 1440 /* ARGSUSED */ 1441 int 1442 freebsd12_closefrom(struct thread *td, struct freebsd12_closefrom_args *uap) 1443 { 1444 u_int lowfd; 1445 1446 AUDIT_ARG_FD(uap->lowfd); 1447 1448 /* 1449 * Treat negative starting file descriptor values identical to 1450 * closefrom(0) which closes all files. 1451 */ 1452 lowfd = MAX(0, uap->lowfd); 1453 return (kern_close_range(td, lowfd, ~0U)); 1454 } 1455 #endif /* COMPAT_FREEBSD12 */ 1456 1457 #if defined(COMPAT_43) 1458 /* 1459 * Return status information about a file descriptor. 1460 */ 1461 #ifndef _SYS_SYSPROTO_H_ 1462 struct ofstat_args { 1463 int fd; 1464 struct ostat *sb; 1465 }; 1466 #endif 1467 /* ARGSUSED */ 1468 int 1469 ofstat(struct thread *td, struct ofstat_args *uap) 1470 { 1471 struct ostat oub; 1472 struct stat ub; 1473 int error; 1474 1475 error = kern_fstat(td, uap->fd, &ub); 1476 if (error == 0) { 1477 cvtstat(&ub, &oub); 1478 error = copyout(&oub, uap->sb, sizeof(oub)); 1479 } 1480 return (error); 1481 } 1482 #endif /* COMPAT_43 */ 1483 1484 #if defined(COMPAT_FREEBSD11) 1485 int 1486 freebsd11_fstat(struct thread *td, struct freebsd11_fstat_args *uap) 1487 { 1488 struct stat sb; 1489 struct freebsd11_stat osb; 1490 int error; 1491 1492 error = kern_fstat(td, uap->fd, &sb); 1493 if (error != 0) 1494 return (error); 1495 error = freebsd11_cvtstat(&sb, &osb); 1496 if (error == 0) 1497 error = copyout(&osb, uap->sb, sizeof(osb)); 1498 return (error); 1499 } 1500 #endif /* COMPAT_FREEBSD11 */ 1501 1502 /* 1503 * Return status information about a file descriptor. 1504 */ 1505 #ifndef _SYS_SYSPROTO_H_ 1506 struct fstat_args { 1507 int fd; 1508 struct stat *sb; 1509 }; 1510 #endif 1511 /* ARGSUSED */ 1512 int 1513 sys_fstat(struct thread *td, struct fstat_args *uap) 1514 { 1515 struct stat ub; 1516 int error; 1517 1518 error = kern_fstat(td, uap->fd, &ub); 1519 if (error == 0) 1520 error = copyout(&ub, uap->sb, sizeof(ub)); 1521 return (error); 1522 } 1523 1524 int 1525 kern_fstat(struct thread *td, int fd, struct stat *sbp) 1526 { 1527 struct file *fp; 1528 int error; 1529 1530 AUDIT_ARG_FD(fd); 1531 1532 error = fget(td, fd, &cap_fstat_rights, &fp); 1533 if (__predict_false(error != 0)) 1534 return (error); 1535 1536 AUDIT_ARG_FILE(td->td_proc, fp); 1537 1538 error = fo_stat(fp, sbp, td->td_ucred, td); 1539 fdrop(fp, td); 1540 #ifdef __STAT_TIME_T_EXT 1541 sbp->st_atim_ext = 0; 1542 sbp->st_mtim_ext = 0; 1543 sbp->st_ctim_ext = 0; 1544 sbp->st_btim_ext = 0; 1545 #endif 1546 #ifdef KTRACE 1547 if (KTRPOINT(td, KTR_STRUCT)) 1548 ktrstat_error(sbp, error); 1549 #endif 1550 return (error); 1551 } 1552 1553 #if defined(COMPAT_FREEBSD11) 1554 /* 1555 * Return status information about a file descriptor. 1556 */ 1557 #ifndef _SYS_SYSPROTO_H_ 1558 struct freebsd11_nfstat_args { 1559 int fd; 1560 struct nstat *sb; 1561 }; 1562 #endif 1563 /* ARGSUSED */ 1564 int 1565 freebsd11_nfstat(struct thread *td, struct freebsd11_nfstat_args *uap) 1566 { 1567 struct nstat nub; 1568 struct stat ub; 1569 int error; 1570 1571 error = kern_fstat(td, uap->fd, &ub); 1572 if (error == 0) { 1573 freebsd11_cvtnstat(&ub, &nub); 1574 error = copyout(&nub, uap->sb, sizeof(nub)); 1575 } 1576 return (error); 1577 } 1578 #endif /* COMPAT_FREEBSD11 */ 1579 1580 /* 1581 * Return pathconf information about a file descriptor. 1582 */ 1583 #ifndef _SYS_SYSPROTO_H_ 1584 struct fpathconf_args { 1585 int fd; 1586 int name; 1587 }; 1588 #endif 1589 /* ARGSUSED */ 1590 int 1591 sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1592 { 1593 long value; 1594 int error; 1595 1596 error = kern_fpathconf(td, uap->fd, uap->name, &value); 1597 if (error == 0) 1598 td->td_retval[0] = value; 1599 return (error); 1600 } 1601 1602 int 1603 kern_fpathconf(struct thread *td, int fd, int name, long *valuep) 1604 { 1605 struct file *fp; 1606 struct vnode *vp; 1607 int error; 1608 1609 error = fget(td, fd, &cap_fpathconf_rights, &fp); 1610 if (error != 0) 1611 return (error); 1612 1613 if (name == _PC_ASYNC_IO) { 1614 *valuep = _POSIX_ASYNCHRONOUS_IO; 1615 goto out; 1616 } 1617 vp = fp->f_vnode; 1618 if (vp != NULL) { 1619 vn_lock(vp, LK_SHARED | LK_RETRY); 1620 error = VOP_PATHCONF(vp, name, valuep); 1621 VOP_UNLOCK(vp); 1622 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1623 if (name != _PC_PIPE_BUF) { 1624 error = EINVAL; 1625 } else { 1626 *valuep = PIPE_BUF; 1627 error = 0; 1628 } 1629 } else { 1630 error = EOPNOTSUPP; 1631 } 1632 out: 1633 fdrop(fp, td); 1634 return (error); 1635 } 1636 1637 /* 1638 * Copy filecaps structure allocating memory for ioctls array if needed. 1639 * 1640 * The last parameter indicates whether the fdtable is locked. If it is not and 1641 * ioctls are encountered, copying fails and the caller must lock the table. 1642 * 1643 * Note that if the table was not locked, the caller has to check the relevant 1644 * sequence counter to determine whether the operation was successful. 1645 */ 1646 bool 1647 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked) 1648 { 1649 size_t size; 1650 1651 if (src->fc_ioctls != NULL && !locked) 1652 return (false); 1653 memcpy(dst, src, sizeof(*src)); 1654 if (src->fc_ioctls == NULL) 1655 return (true); 1656 1657 KASSERT(src->fc_nioctls > 0, 1658 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1659 1660 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1661 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1662 memcpy(dst->fc_ioctls, src->fc_ioctls, size); 1663 return (true); 1664 } 1665 1666 static u_long * 1667 filecaps_copy_prep(const struct filecaps *src) 1668 { 1669 u_long *ioctls; 1670 size_t size; 1671 1672 if (__predict_true(src->fc_ioctls == NULL)) 1673 return (NULL); 1674 1675 KASSERT(src->fc_nioctls > 0, 1676 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1677 1678 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1679 ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1680 return (ioctls); 1681 } 1682 1683 static void 1684 filecaps_copy_finish(const struct filecaps *src, struct filecaps *dst, 1685 u_long *ioctls) 1686 { 1687 size_t size; 1688 1689 *dst = *src; 1690 if (__predict_true(src->fc_ioctls == NULL)) { 1691 MPASS(ioctls == NULL); 1692 return; 1693 } 1694 1695 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1696 dst->fc_ioctls = ioctls; 1697 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1698 } 1699 1700 /* 1701 * Move filecaps structure to the new place and clear the old place. 1702 */ 1703 void 1704 filecaps_move(struct filecaps *src, struct filecaps *dst) 1705 { 1706 1707 *dst = *src; 1708 bzero(src, sizeof(*src)); 1709 } 1710 1711 /* 1712 * Fill the given filecaps structure with full rights. 1713 */ 1714 static void 1715 filecaps_fill(struct filecaps *fcaps) 1716 { 1717 1718 CAP_ALL(&fcaps->fc_rights); 1719 fcaps->fc_ioctls = NULL; 1720 fcaps->fc_nioctls = -1; 1721 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1722 } 1723 1724 /* 1725 * Free memory allocated within filecaps structure. 1726 */ 1727 void 1728 filecaps_free(struct filecaps *fcaps) 1729 { 1730 1731 free(fcaps->fc_ioctls, M_FILECAPS); 1732 bzero(fcaps, sizeof(*fcaps)); 1733 } 1734 1735 static u_long * 1736 filecaps_free_prep(struct filecaps *fcaps) 1737 { 1738 u_long *ioctls; 1739 1740 ioctls = fcaps->fc_ioctls; 1741 bzero(fcaps, sizeof(*fcaps)); 1742 return (ioctls); 1743 } 1744 1745 static void 1746 filecaps_free_finish(u_long *ioctls) 1747 { 1748 1749 free(ioctls, M_FILECAPS); 1750 } 1751 1752 /* 1753 * Validate the given filecaps structure. 1754 */ 1755 static void 1756 filecaps_validate(const struct filecaps *fcaps, const char *func) 1757 { 1758 1759 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1760 ("%s: invalid rights", func)); 1761 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1762 ("%s: invalid fcntls", func)); 1763 KASSERT(fcaps->fc_fcntls == 0 || 1764 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1765 ("%s: fcntls without CAP_FCNTL", func)); 1766 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1767 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1768 ("%s: invalid ioctls", func)); 1769 KASSERT(fcaps->fc_nioctls == 0 || 1770 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1771 ("%s: ioctls without CAP_IOCTL", func)); 1772 } 1773 1774 static void 1775 fdgrowtable_exp(struct filedesc *fdp, int nfd) 1776 { 1777 int nfd1; 1778 1779 FILEDESC_XLOCK_ASSERT(fdp); 1780 1781 nfd1 = fdp->fd_nfiles * 2; 1782 if (nfd1 < nfd) 1783 nfd1 = nfd; 1784 fdgrowtable(fdp, nfd1); 1785 } 1786 1787 /* 1788 * Grow the file table to accommodate (at least) nfd descriptors. 1789 */ 1790 static void 1791 fdgrowtable(struct filedesc *fdp, int nfd) 1792 { 1793 struct filedesc0 *fdp0; 1794 struct freetable *ft; 1795 struct fdescenttbl *ntable; 1796 struct fdescenttbl *otable; 1797 int nnfiles, onfiles; 1798 NDSLOTTYPE *nmap, *omap; 1799 1800 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1801 1802 /* save old values */ 1803 onfiles = fdp->fd_nfiles; 1804 otable = fdp->fd_files; 1805 omap = fdp->fd_map; 1806 1807 /* compute the size of the new table */ 1808 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1809 if (nnfiles <= onfiles) 1810 /* the table is already large enough */ 1811 return; 1812 1813 /* 1814 * Allocate a new table. We need enough space for the number of 1815 * entries, file entries themselves and the struct freetable we will use 1816 * when we decommission the table and place it on the freelist. 1817 * We place the struct freetable in the middle so we don't have 1818 * to worry about padding. 1819 */ 1820 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) + 1821 nnfiles * sizeof(ntable->fdt_ofiles[0]) + 1822 sizeof(struct freetable), 1823 M_FILEDESC, M_ZERO | M_WAITOK); 1824 /* copy the old data */ 1825 ntable->fdt_nfiles = nnfiles; 1826 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles, 1827 onfiles * sizeof(ntable->fdt_ofiles[0])); 1828 1829 /* 1830 * Allocate a new map only if the old is not large enough. It will 1831 * grow at a slower rate than the table as it can map more 1832 * entries than the table can hold. 1833 */ 1834 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1835 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1836 M_ZERO | M_WAITOK); 1837 /* copy over the old data and update the pointer */ 1838 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1839 fdp->fd_map = nmap; 1840 } 1841 1842 /* 1843 * Make sure that ntable is correctly initialized before we replace 1844 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent 1845 * data. 1846 */ 1847 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable); 1848 1849 /* 1850 * Free the old file table when not shared by other threads or processes. 1851 * The old file table is considered to be shared when either are true: 1852 * - The process has more than one thread. 1853 * - The file descriptor table has been shared via fdshare(). 1854 * 1855 * When shared, the old file table will be placed on a freelist 1856 * which will be processed when the struct filedesc is released. 1857 * 1858 * Note that if onfiles == NDFILE, we're dealing with the original 1859 * static allocation contained within (struct filedesc0 *)fdp, 1860 * which must not be freed. 1861 */ 1862 if (onfiles > NDFILE) { 1863 /* 1864 * Note we may be called here from fdinit while allocating a 1865 * table for a new process in which case ->p_fd points 1866 * elsewhere. 1867 */ 1868 if (curproc->p_fd != fdp || FILEDESC_IS_ONLY_USER(fdp)) { 1869 free(otable, M_FILEDESC); 1870 } else { 1871 ft = (struct freetable *)&otable->fdt_ofiles[onfiles]; 1872 fdp0 = (struct filedesc0 *)fdp; 1873 ft->ft_table = otable; 1874 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1875 } 1876 } 1877 /* 1878 * The map does not have the same possibility of threads still 1879 * holding references to it. So always free it as long as it 1880 * does not reference the original static allocation. 1881 */ 1882 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1883 free(omap, M_FILEDESC); 1884 } 1885 1886 /* 1887 * Allocate a file descriptor for the process. 1888 */ 1889 int 1890 fdalloc(struct thread *td, int minfd, int *result) 1891 { 1892 struct proc *p = td->td_proc; 1893 struct filedesc *fdp = p->p_fd; 1894 int fd, maxfd, allocfd; 1895 #ifdef RACCT 1896 int error; 1897 #endif 1898 1899 FILEDESC_XLOCK_ASSERT(fdp); 1900 1901 if (fdp->fd_freefile > minfd) 1902 minfd = fdp->fd_freefile; 1903 1904 maxfd = getmaxfd(td); 1905 1906 /* 1907 * Search the bitmap for a free descriptor starting at minfd. 1908 * If none is found, grow the file table. 1909 */ 1910 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1911 if (__predict_false(fd >= maxfd)) 1912 return (EMFILE); 1913 if (__predict_false(fd >= fdp->fd_nfiles)) { 1914 allocfd = min(fd * 2, maxfd); 1915 #ifdef RACCT 1916 if (RACCT_ENABLED()) { 1917 error = racct_set_unlocked(p, RACCT_NOFILE, allocfd); 1918 if (error != 0) 1919 return (EMFILE); 1920 } 1921 #endif 1922 /* 1923 * fd is already equal to first free descriptor >= minfd, so 1924 * we only need to grow the table and we are done. 1925 */ 1926 fdgrowtable_exp(fdp, allocfd); 1927 } 1928 1929 /* 1930 * Perform some sanity checks, then mark the file descriptor as 1931 * used and return it to the caller. 1932 */ 1933 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1934 ("invalid descriptor %d", fd)); 1935 KASSERT(!fdisused(fdp, fd), 1936 ("fd_first_free() returned non-free descriptor")); 1937 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1938 ("file descriptor isn't free")); 1939 fdused(fdp, fd); 1940 *result = fd; 1941 return (0); 1942 } 1943 1944 /* 1945 * Allocate n file descriptors for the process. 1946 */ 1947 int 1948 fdallocn(struct thread *td, int minfd, int *fds, int n) 1949 { 1950 struct proc *p = td->td_proc; 1951 struct filedesc *fdp = p->p_fd; 1952 int i; 1953 1954 FILEDESC_XLOCK_ASSERT(fdp); 1955 1956 for (i = 0; i < n; i++) 1957 if (fdalloc(td, 0, &fds[i]) != 0) 1958 break; 1959 1960 if (i < n) { 1961 for (i--; i >= 0; i--) 1962 fdunused(fdp, fds[i]); 1963 return (EMFILE); 1964 } 1965 1966 return (0); 1967 } 1968 1969 /* 1970 * Create a new open file structure and allocate a file descriptor for the 1971 * process that refers to it. We add one reference to the file for the 1972 * descriptor table and one reference for resultfp. This is to prevent us 1973 * being preempted and the entry in the descriptor table closed after we 1974 * release the FILEDESC lock. 1975 */ 1976 int 1977 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags, 1978 struct filecaps *fcaps) 1979 { 1980 struct file *fp; 1981 int error, fd; 1982 1983 MPASS(resultfp != NULL); 1984 MPASS(resultfd != NULL); 1985 1986 error = _falloc_noinstall(td, &fp, 2); 1987 if (__predict_false(error != 0)) { 1988 return (error); 1989 } 1990 1991 error = finstall_refed(td, fp, &fd, flags, fcaps); 1992 if (__predict_false(error != 0)) { 1993 falloc_abort(td, fp); 1994 return (error); 1995 } 1996 1997 *resultfp = fp; 1998 *resultfd = fd; 1999 2000 return (0); 2001 } 2002 2003 /* 2004 * Create a new open file structure without allocating a file descriptor. 2005 */ 2006 int 2007 _falloc_noinstall(struct thread *td, struct file **resultfp, u_int n) 2008 { 2009 struct file *fp; 2010 int maxuserfiles = maxfiles - (maxfiles / 20); 2011 int openfiles_new; 2012 static struct timeval lastfail; 2013 static int curfail; 2014 2015 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 2016 MPASS(n > 0); 2017 2018 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1; 2019 if ((openfiles_new >= maxuserfiles && 2020 priv_check(td, PRIV_MAXFILES) != 0) || 2021 openfiles_new >= maxfiles) { 2022 atomic_subtract_int(&openfiles, 1); 2023 if (ppsratecheck(&lastfail, &curfail, 1)) { 2024 printf("kern.maxfiles limit exceeded by uid %i, (%s) " 2025 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm); 2026 } 2027 return (ENFILE); 2028 } 2029 fp = uma_zalloc(file_zone, M_WAITOK); 2030 bzero(fp, sizeof(*fp)); 2031 refcount_init(&fp->f_count, n); 2032 fp->f_cred = crhold(td->td_ucred); 2033 fp->f_ops = &badfileops; 2034 *resultfp = fp; 2035 return (0); 2036 } 2037 2038 void 2039 falloc_abort(struct thread *td, struct file *fp) 2040 { 2041 2042 /* 2043 * For assertion purposes. 2044 */ 2045 refcount_init(&fp->f_count, 0); 2046 _fdrop(fp, td); 2047 } 2048 2049 /* 2050 * Install a file in a file descriptor table. 2051 */ 2052 void 2053 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags, 2054 struct filecaps *fcaps) 2055 { 2056 struct filedescent *fde; 2057 2058 MPASS(fp != NULL); 2059 if (fcaps != NULL) 2060 filecaps_validate(fcaps, __func__); 2061 FILEDESC_XLOCK_ASSERT(fdp); 2062 2063 fde = &fdp->fd_ofiles[fd]; 2064 #ifdef CAPABILITIES 2065 seqc_write_begin(&fde->fde_seqc); 2066 #endif 2067 fde->fde_file = fp; 2068 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0; 2069 if (fcaps != NULL) 2070 filecaps_move(fcaps, &fde->fde_caps); 2071 else 2072 filecaps_fill(&fde->fde_caps); 2073 #ifdef CAPABILITIES 2074 seqc_write_end(&fde->fde_seqc); 2075 #endif 2076 } 2077 2078 int 2079 finstall_refed(struct thread *td, struct file *fp, int *fd, int flags, 2080 struct filecaps *fcaps) 2081 { 2082 struct filedesc *fdp = td->td_proc->p_fd; 2083 int error; 2084 2085 MPASS(fd != NULL); 2086 2087 FILEDESC_XLOCK(fdp); 2088 error = fdalloc(td, 0, fd); 2089 if (__predict_true(error == 0)) { 2090 _finstall(fdp, fp, *fd, flags, fcaps); 2091 } 2092 FILEDESC_XUNLOCK(fdp); 2093 return (error); 2094 } 2095 2096 int 2097 finstall(struct thread *td, struct file *fp, int *fd, int flags, 2098 struct filecaps *fcaps) 2099 { 2100 int error; 2101 2102 MPASS(fd != NULL); 2103 2104 if (!fhold(fp)) 2105 return (EBADF); 2106 error = finstall_refed(td, fp, fd, flags, fcaps); 2107 if (__predict_false(error != 0)) { 2108 fdrop(fp, td); 2109 } 2110 return (error); 2111 } 2112 2113 /* 2114 * Build a new filedesc structure from another. 2115 * 2116 * If fdp is not NULL, return with it shared locked. 2117 */ 2118 struct filedesc * 2119 fdinit(struct filedesc *fdp, bool prepfiles, int *lastfile) 2120 { 2121 struct filedesc0 *newfdp0; 2122 struct filedesc *newfdp; 2123 2124 if (prepfiles) 2125 MPASS(lastfile != NULL); 2126 else 2127 MPASS(lastfile == NULL); 2128 2129 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO); 2130 newfdp = &newfdp0->fd_fd; 2131 2132 /* Create the file descriptor table. */ 2133 FILEDESC_LOCK_INIT(newfdp); 2134 refcount_init(&newfdp->fd_refcnt, 1); 2135 refcount_init(&newfdp->fd_holdcnt, 1); 2136 newfdp->fd_map = newfdp0->fd_dmap; 2137 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles; 2138 newfdp->fd_files->fdt_nfiles = NDFILE; 2139 2140 if (fdp == NULL) 2141 return (newfdp); 2142 2143 FILEDESC_SLOCK(fdp); 2144 if (!prepfiles) { 2145 FILEDESC_SUNLOCK(fdp); 2146 return (newfdp); 2147 } 2148 2149 for (;;) { 2150 *lastfile = fdlastfile(fdp); 2151 if (*lastfile < newfdp->fd_nfiles) 2152 break; 2153 FILEDESC_SUNLOCK(fdp); 2154 fdgrowtable(newfdp, *lastfile + 1); 2155 FILEDESC_SLOCK(fdp); 2156 } 2157 2158 return (newfdp); 2159 } 2160 2161 /* 2162 * Build a pwddesc structure from another. 2163 * Copy the current, root, and jail root vnode references. 2164 * 2165 * If pdp is not NULL, return with it shared locked. 2166 */ 2167 struct pwddesc * 2168 pdinit(struct pwddesc *pdp, bool keeplock) 2169 { 2170 struct pwddesc *newpdp; 2171 struct pwd *newpwd; 2172 2173 newpdp = malloc(sizeof(*newpdp), M_PWDDESC, M_WAITOK | M_ZERO); 2174 2175 PWDDESC_LOCK_INIT(newpdp); 2176 refcount_init(&newpdp->pd_refcount, 1); 2177 newpdp->pd_cmask = CMASK; 2178 2179 if (pdp == NULL) { 2180 newpwd = pwd_alloc(); 2181 smr_serialized_store(&newpdp->pd_pwd, newpwd, true); 2182 return (newpdp); 2183 } 2184 2185 PWDDESC_XLOCK(pdp); 2186 newpwd = pwd_hold_pwddesc(pdp); 2187 smr_serialized_store(&newpdp->pd_pwd, newpwd, true); 2188 if (!keeplock) 2189 PWDDESC_XUNLOCK(pdp); 2190 return (newpdp); 2191 } 2192 2193 static struct filedesc * 2194 fdhold(struct proc *p) 2195 { 2196 struct filedesc *fdp; 2197 2198 PROC_LOCK_ASSERT(p, MA_OWNED); 2199 fdp = p->p_fd; 2200 if (fdp != NULL) 2201 refcount_acquire(&fdp->fd_holdcnt); 2202 return (fdp); 2203 } 2204 2205 static struct pwddesc * 2206 pdhold(struct proc *p) 2207 { 2208 struct pwddesc *pdp; 2209 2210 PROC_LOCK_ASSERT(p, MA_OWNED); 2211 pdp = p->p_pd; 2212 if (pdp != NULL) 2213 refcount_acquire(&pdp->pd_refcount); 2214 return (pdp); 2215 } 2216 2217 static void 2218 fddrop(struct filedesc *fdp) 2219 { 2220 2221 if (refcount_load(&fdp->fd_holdcnt) > 1) { 2222 if (refcount_release(&fdp->fd_holdcnt) == 0) 2223 return; 2224 } 2225 2226 FILEDESC_LOCK_DESTROY(fdp); 2227 uma_zfree(filedesc0_zone, fdp); 2228 } 2229 2230 static void 2231 pddrop(struct pwddesc *pdp) 2232 { 2233 struct pwd *pwd; 2234 2235 if (refcount_release_if_not_last(&pdp->pd_refcount)) 2236 return; 2237 2238 PWDDESC_XLOCK(pdp); 2239 if (refcount_release(&pdp->pd_refcount) == 0) { 2240 PWDDESC_XUNLOCK(pdp); 2241 return; 2242 } 2243 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 2244 pwd_set(pdp, NULL); 2245 PWDDESC_XUNLOCK(pdp); 2246 pwd_drop(pwd); 2247 2248 PWDDESC_LOCK_DESTROY(pdp); 2249 free(pdp, M_PWDDESC); 2250 } 2251 2252 /* 2253 * Share a filedesc structure. 2254 */ 2255 struct filedesc * 2256 fdshare(struct filedesc *fdp) 2257 { 2258 2259 refcount_acquire(&fdp->fd_refcnt); 2260 return (fdp); 2261 } 2262 2263 /* 2264 * Share a pwddesc structure. 2265 */ 2266 struct pwddesc * 2267 pdshare(struct pwddesc *pdp) 2268 { 2269 refcount_acquire(&pdp->pd_refcount); 2270 return (pdp); 2271 } 2272 2273 /* 2274 * Unshare a filedesc structure, if necessary by making a copy 2275 */ 2276 void 2277 fdunshare(struct thread *td) 2278 { 2279 struct filedesc *tmp; 2280 struct proc *p = td->td_proc; 2281 2282 if (refcount_load(&p->p_fd->fd_refcnt) == 1) 2283 return; 2284 2285 tmp = fdcopy(p->p_fd); 2286 fdescfree(td); 2287 p->p_fd = tmp; 2288 } 2289 2290 /* 2291 * Unshare a pwddesc structure. 2292 */ 2293 void 2294 pdunshare(struct thread *td) 2295 { 2296 struct pwddesc *pdp; 2297 struct proc *p; 2298 2299 p = td->td_proc; 2300 /* Not shared. */ 2301 if (p->p_pd->pd_refcount == 1) 2302 return; 2303 2304 pdp = pdcopy(p->p_pd); 2305 pdescfree(td); 2306 p->p_pd = pdp; 2307 } 2308 2309 void 2310 fdinstall_remapped(struct thread *td, struct filedesc *fdp) 2311 { 2312 2313 fdescfree(td); 2314 td->td_proc->p_fd = fdp; 2315 } 2316 2317 /* 2318 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 2319 * this is to ease callers, not catch errors. 2320 */ 2321 struct filedesc * 2322 fdcopy(struct filedesc *fdp) 2323 { 2324 struct filedesc *newfdp; 2325 struct filedescent *nfde, *ofde; 2326 int i, lastfile; 2327 2328 MPASS(fdp != NULL); 2329 2330 newfdp = fdinit(fdp, true, &lastfile); 2331 /* copy all passable descriptors (i.e. not kqueue) */ 2332 newfdp->fd_freefile = -1; 2333 for (i = 0; i <= lastfile; ++i) { 2334 ofde = &fdp->fd_ofiles[i]; 2335 if (ofde->fde_file == NULL || 2336 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0 || 2337 !fhold(ofde->fde_file)) { 2338 if (newfdp->fd_freefile == -1) 2339 newfdp->fd_freefile = i; 2340 continue; 2341 } 2342 nfde = &newfdp->fd_ofiles[i]; 2343 *nfde = *ofde; 2344 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 2345 fdused_init(newfdp, i); 2346 } 2347 if (newfdp->fd_freefile == -1) 2348 newfdp->fd_freefile = i; 2349 FILEDESC_SUNLOCK(fdp); 2350 return (newfdp); 2351 } 2352 2353 /* 2354 * Copy a pwddesc structure. 2355 */ 2356 struct pwddesc * 2357 pdcopy(struct pwddesc *pdp) 2358 { 2359 struct pwddesc *newpdp; 2360 2361 MPASS(pdp != NULL); 2362 2363 newpdp = pdinit(pdp, true); 2364 newpdp->pd_cmask = pdp->pd_cmask; 2365 PWDDESC_XUNLOCK(pdp); 2366 return (newpdp); 2367 } 2368 2369 /* 2370 * Copies a filedesc structure, while remapping all file descriptors 2371 * stored inside using a translation table. 2372 * 2373 * File descriptors are copied over to the new file descriptor table, 2374 * regardless of whether the close-on-exec flag is set. 2375 */ 2376 int 2377 fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds, 2378 struct filedesc **ret) 2379 { 2380 struct filedesc *newfdp; 2381 struct filedescent *nfde, *ofde; 2382 int error, i, lastfile; 2383 2384 MPASS(fdp != NULL); 2385 2386 newfdp = fdinit(fdp, true, &lastfile); 2387 if (nfds > lastfile + 1) { 2388 /* New table cannot be larger than the old one. */ 2389 error = E2BIG; 2390 goto bad; 2391 } 2392 /* Copy all passable descriptors (i.e. not kqueue). */ 2393 newfdp->fd_freefile = nfds; 2394 for (i = 0; i < nfds; ++i) { 2395 if (fds[i] < 0 || fds[i] > lastfile) { 2396 /* File descriptor out of bounds. */ 2397 error = EBADF; 2398 goto bad; 2399 } 2400 ofde = &fdp->fd_ofiles[fds[i]]; 2401 if (ofde->fde_file == NULL) { 2402 /* Unused file descriptor. */ 2403 error = EBADF; 2404 goto bad; 2405 } 2406 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) { 2407 /* File descriptor cannot be passed. */ 2408 error = EINVAL; 2409 goto bad; 2410 } 2411 if (!fhold(ofde->fde_file)) { 2412 error = EBADF; 2413 goto bad; 2414 } 2415 nfde = &newfdp->fd_ofiles[i]; 2416 *nfde = *ofde; 2417 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true); 2418 fdused_init(newfdp, i); 2419 } 2420 FILEDESC_SUNLOCK(fdp); 2421 *ret = newfdp; 2422 return (0); 2423 bad: 2424 FILEDESC_SUNLOCK(fdp); 2425 fdescfree_remapped(newfdp); 2426 return (error); 2427 } 2428 2429 /* 2430 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e. 2431 * one of processes using it exits) and the table used to be shared. 2432 */ 2433 static void 2434 fdclearlocks(struct thread *td) 2435 { 2436 struct filedesc *fdp; 2437 struct filedesc_to_leader *fdtol; 2438 struct flock lf; 2439 struct file *fp; 2440 struct proc *p; 2441 struct vnode *vp; 2442 int i, lastfile; 2443 2444 p = td->td_proc; 2445 fdp = p->p_fd; 2446 fdtol = p->p_fdtol; 2447 MPASS(fdtol != NULL); 2448 2449 FILEDESC_XLOCK(fdp); 2450 KASSERT(fdtol->fdl_refcount > 0, 2451 ("filedesc_to_refcount botch: fdl_refcount=%d", 2452 fdtol->fdl_refcount)); 2453 if (fdtol->fdl_refcount == 1 && 2454 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2455 lastfile = fdlastfile(fdp); 2456 for (i = 0; i <= lastfile; i++) { 2457 fp = fdp->fd_ofiles[i].fde_file; 2458 if (fp == NULL || fp->f_type != DTYPE_VNODE || 2459 !fhold(fp)) 2460 continue; 2461 FILEDESC_XUNLOCK(fdp); 2462 lf.l_whence = SEEK_SET; 2463 lf.l_start = 0; 2464 lf.l_len = 0; 2465 lf.l_type = F_UNLCK; 2466 vp = fp->f_vnode; 2467 (void) VOP_ADVLOCK(vp, 2468 (caddr_t)p->p_leader, F_UNLCK, 2469 &lf, F_POSIX); 2470 FILEDESC_XLOCK(fdp); 2471 fdrop(fp, td); 2472 } 2473 } 2474 retry: 2475 if (fdtol->fdl_refcount == 1) { 2476 if (fdp->fd_holdleaderscount > 0 && 2477 (p->p_leader->p_flag & P_ADVLOCK) != 0) { 2478 /* 2479 * close() or kern_dup() has cleared a reference 2480 * in a shared file descriptor table. 2481 */ 2482 fdp->fd_holdleaderswakeup = 1; 2483 sx_sleep(&fdp->fd_holdleaderscount, 2484 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2485 goto retry; 2486 } 2487 if (fdtol->fdl_holdcount > 0) { 2488 /* 2489 * Ensure that fdtol->fdl_leader remains 2490 * valid in closef(). 2491 */ 2492 fdtol->fdl_wakeup = 1; 2493 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2494 "fdlhold", 0); 2495 goto retry; 2496 } 2497 } 2498 fdtol->fdl_refcount--; 2499 if (fdtol->fdl_refcount == 0 && 2500 fdtol->fdl_holdcount == 0) { 2501 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2502 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2503 } else 2504 fdtol = NULL; 2505 p->p_fdtol = NULL; 2506 FILEDESC_XUNLOCK(fdp); 2507 if (fdtol != NULL) 2508 free(fdtol, M_FILEDESC_TO_LEADER); 2509 } 2510 2511 /* 2512 * Release a filedesc structure. 2513 */ 2514 static void 2515 fdescfree_fds(struct thread *td, struct filedesc *fdp, bool needclose) 2516 { 2517 struct filedesc0 *fdp0; 2518 struct freetable *ft, *tft; 2519 struct filedescent *fde; 2520 struct file *fp; 2521 int i, lastfile; 2522 2523 KASSERT(refcount_load(&fdp->fd_refcnt) == 0, 2524 ("%s: fd table %p carries references", __func__, fdp)); 2525 2526 /* 2527 * Serialize with threads iterating over the table, if any. 2528 */ 2529 if (refcount_load(&fdp->fd_holdcnt) > 1) { 2530 FILEDESC_XLOCK(fdp); 2531 FILEDESC_XUNLOCK(fdp); 2532 } 2533 2534 lastfile = fdlastfile_single(fdp); 2535 for (i = 0; i <= lastfile; i++) { 2536 fde = &fdp->fd_ofiles[i]; 2537 fp = fde->fde_file; 2538 if (fp != NULL) { 2539 fdefree_last(fde); 2540 if (needclose) 2541 (void) closef(fp, td); 2542 else 2543 fdrop(fp, td); 2544 } 2545 } 2546 2547 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2548 free(fdp->fd_map, M_FILEDESC); 2549 if (fdp->fd_nfiles > NDFILE) 2550 free(fdp->fd_files, M_FILEDESC); 2551 2552 fdp0 = (struct filedesc0 *)fdp; 2553 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft) 2554 free(ft->ft_table, M_FILEDESC); 2555 2556 fddrop(fdp); 2557 } 2558 2559 void 2560 fdescfree(struct thread *td) 2561 { 2562 struct proc *p; 2563 struct filedesc *fdp; 2564 2565 p = td->td_proc; 2566 fdp = p->p_fd; 2567 MPASS(fdp != NULL); 2568 2569 #ifdef RACCT 2570 if (RACCT_ENABLED()) 2571 racct_set_unlocked(p, RACCT_NOFILE, 0); 2572 #endif 2573 2574 if (p->p_fdtol != NULL) 2575 fdclearlocks(td); 2576 2577 PROC_LOCK(p); 2578 p->p_fd = NULL; 2579 PROC_UNLOCK(p); 2580 2581 if (refcount_release(&fdp->fd_refcnt) == 0) 2582 return; 2583 2584 fdescfree_fds(td, fdp, 1); 2585 } 2586 2587 void 2588 pdescfree(struct thread *td) 2589 { 2590 struct proc *p; 2591 struct pwddesc *pdp; 2592 2593 p = td->td_proc; 2594 pdp = p->p_pd; 2595 MPASS(pdp != NULL); 2596 2597 PROC_LOCK(p); 2598 p->p_pd = NULL; 2599 PROC_UNLOCK(p); 2600 2601 pddrop(pdp); 2602 } 2603 2604 void 2605 fdescfree_remapped(struct filedesc *fdp) 2606 { 2607 #ifdef INVARIANTS 2608 /* fdescfree_fds() asserts that fd_refcnt == 0. */ 2609 if (!refcount_release(&fdp->fd_refcnt)) 2610 panic("%s: fd table %p has extra references", __func__, fdp); 2611 #endif 2612 fdescfree_fds(curthread, fdp, 0); 2613 } 2614 2615 /* 2616 * For setugid programs, we don't want to people to use that setugidness 2617 * to generate error messages which write to a file which otherwise would 2618 * otherwise be off-limits to the process. We check for filesystems where 2619 * the vnode can change out from under us after execve (like [lin]procfs). 2620 * 2621 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is 2622 * sufficient. We also don't check for setugidness since we know we are. 2623 */ 2624 static bool 2625 is_unsafe(struct file *fp) 2626 { 2627 struct vnode *vp; 2628 2629 if (fp->f_type != DTYPE_VNODE) 2630 return (false); 2631 2632 vp = fp->f_vnode; 2633 return ((vp->v_vflag & VV_PROCDEP) != 0); 2634 } 2635 2636 /* 2637 * Make this setguid thing safe, if at all possible. 2638 */ 2639 void 2640 fdsetugidsafety(struct thread *td) 2641 { 2642 struct filedesc *fdp; 2643 struct file *fp; 2644 int i; 2645 2646 fdp = td->td_proc->p_fd; 2647 KASSERT(refcount_load(&fdp->fd_refcnt) == 1, 2648 ("the fdtable should not be shared")); 2649 MPASS(fdp->fd_nfiles >= 3); 2650 for (i = 0; i <= 2; i++) { 2651 fp = fdp->fd_ofiles[i].fde_file; 2652 if (fp != NULL && is_unsafe(fp)) { 2653 FILEDESC_XLOCK(fdp); 2654 knote_fdclose(td, i); 2655 /* 2656 * NULL-out descriptor prior to close to avoid 2657 * a race while close blocks. 2658 */ 2659 fdfree(fdp, i); 2660 FILEDESC_XUNLOCK(fdp); 2661 (void) closef(fp, td); 2662 } 2663 } 2664 } 2665 2666 /* 2667 * If a specific file object occupies a specific file descriptor, close the 2668 * file descriptor entry and drop a reference on the file object. This is a 2669 * convenience function to handle a subsequent error in a function that calls 2670 * falloc() that handles the race that another thread might have closed the 2671 * file descriptor out from under the thread creating the file object. 2672 */ 2673 void 2674 fdclose(struct thread *td, struct file *fp, int idx) 2675 { 2676 struct filedesc *fdp = td->td_proc->p_fd; 2677 2678 FILEDESC_XLOCK(fdp); 2679 if (fdp->fd_ofiles[idx].fde_file == fp) { 2680 fdfree(fdp, idx); 2681 FILEDESC_XUNLOCK(fdp); 2682 fdrop(fp, td); 2683 } else 2684 FILEDESC_XUNLOCK(fdp); 2685 } 2686 2687 /* 2688 * Close any files on exec? 2689 */ 2690 void 2691 fdcloseexec(struct thread *td) 2692 { 2693 struct filedesc *fdp; 2694 struct filedescent *fde; 2695 struct file *fp; 2696 int i, lastfile; 2697 2698 fdp = td->td_proc->p_fd; 2699 KASSERT(refcount_load(&fdp->fd_refcnt) == 1, 2700 ("the fdtable should not be shared")); 2701 lastfile = fdlastfile_single(fdp); 2702 for (i = 0; i <= lastfile; i++) { 2703 fde = &fdp->fd_ofiles[i]; 2704 fp = fde->fde_file; 2705 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2706 (fde->fde_flags & UF_EXCLOSE))) { 2707 FILEDESC_XLOCK(fdp); 2708 fdfree(fdp, i); 2709 (void) closefp(fdp, i, fp, td, false, false); 2710 FILEDESC_UNLOCK_ASSERT(fdp); 2711 } 2712 } 2713 } 2714 2715 /* 2716 * It is unsafe for set[ug]id processes to be started with file 2717 * descriptors 0..2 closed, as these descriptors are given implicit 2718 * significance in the Standard C library. fdcheckstd() will create a 2719 * descriptor referencing /dev/null for each of stdin, stdout, and 2720 * stderr that is not already open. 2721 */ 2722 int 2723 fdcheckstd(struct thread *td) 2724 { 2725 struct filedesc *fdp; 2726 register_t save; 2727 int i, error, devnull; 2728 2729 fdp = td->td_proc->p_fd; 2730 KASSERT(refcount_load(&fdp->fd_refcnt) == 1, 2731 ("the fdtable should not be shared")); 2732 MPASS(fdp->fd_nfiles >= 3); 2733 devnull = -1; 2734 for (i = 0; i <= 2; i++) { 2735 if (fdp->fd_ofiles[i].fde_file != NULL) 2736 continue; 2737 2738 save = td->td_retval[0]; 2739 if (devnull != -1) { 2740 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i); 2741 } else { 2742 error = kern_openat(td, AT_FDCWD, "/dev/null", 2743 UIO_SYSSPACE, O_RDWR, 0); 2744 if (error == 0) { 2745 devnull = td->td_retval[0]; 2746 KASSERT(devnull == i, ("we didn't get our fd")); 2747 } 2748 } 2749 td->td_retval[0] = save; 2750 if (error != 0) 2751 return (error); 2752 } 2753 return (0); 2754 } 2755 2756 /* 2757 * Internal form of close. Decrement reference count on file structure. 2758 * Note: td may be NULL when closing a file that was being passed in a 2759 * message. 2760 */ 2761 int 2762 closef(struct file *fp, struct thread *td) 2763 { 2764 struct vnode *vp; 2765 struct flock lf; 2766 struct filedesc_to_leader *fdtol; 2767 struct filedesc *fdp; 2768 2769 MPASS(td != NULL); 2770 2771 /* 2772 * POSIX record locking dictates that any close releases ALL 2773 * locks owned by this process. This is handled by setting 2774 * a flag in the unlock to free ONLY locks obeying POSIX 2775 * semantics, and not to free BSD-style file locks. 2776 * If the descriptor was in a message, POSIX-style locks 2777 * aren't passed with the descriptor, and the thread pointer 2778 * will be NULL. Callers should be careful only to pass a 2779 * NULL thread pointer when there really is no owning 2780 * context that might have locks, or the locks will be 2781 * leaked. 2782 */ 2783 if (fp->f_type == DTYPE_VNODE) { 2784 vp = fp->f_vnode; 2785 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2786 lf.l_whence = SEEK_SET; 2787 lf.l_start = 0; 2788 lf.l_len = 0; 2789 lf.l_type = F_UNLCK; 2790 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2791 F_UNLCK, &lf, F_POSIX); 2792 } 2793 fdtol = td->td_proc->p_fdtol; 2794 if (fdtol != NULL) { 2795 /* 2796 * Handle special case where file descriptor table is 2797 * shared between multiple process leaders. 2798 */ 2799 fdp = td->td_proc->p_fd; 2800 FILEDESC_XLOCK(fdp); 2801 for (fdtol = fdtol->fdl_next; 2802 fdtol != td->td_proc->p_fdtol; 2803 fdtol = fdtol->fdl_next) { 2804 if ((fdtol->fdl_leader->p_flag & 2805 P_ADVLOCK) == 0) 2806 continue; 2807 fdtol->fdl_holdcount++; 2808 FILEDESC_XUNLOCK(fdp); 2809 lf.l_whence = SEEK_SET; 2810 lf.l_start = 0; 2811 lf.l_len = 0; 2812 lf.l_type = F_UNLCK; 2813 vp = fp->f_vnode; 2814 (void) VOP_ADVLOCK(vp, 2815 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2816 F_POSIX); 2817 FILEDESC_XLOCK(fdp); 2818 fdtol->fdl_holdcount--; 2819 if (fdtol->fdl_holdcount == 0 && 2820 fdtol->fdl_wakeup != 0) { 2821 fdtol->fdl_wakeup = 0; 2822 wakeup(fdtol); 2823 } 2824 } 2825 FILEDESC_XUNLOCK(fdp); 2826 } 2827 } 2828 return (fdrop_close(fp, td)); 2829 } 2830 2831 /* 2832 * Hack for file descriptor passing code. 2833 */ 2834 void 2835 closef_nothread(struct file *fp) 2836 { 2837 2838 fdrop(fp, NULL); 2839 } 2840 2841 /* 2842 * Initialize the file pointer with the specified properties. 2843 * 2844 * The ops are set with release semantics to be certain that the flags, type, 2845 * and data are visible when ops is. This is to prevent ops methods from being 2846 * called with bad data. 2847 */ 2848 void 2849 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2850 { 2851 fp->f_data = data; 2852 fp->f_flag = flag; 2853 fp->f_type = type; 2854 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2855 } 2856 2857 void 2858 finit_vnode(struct file *fp, u_int flag, void *data, struct fileops *ops) 2859 { 2860 fp->f_seqcount[UIO_READ] = 1; 2861 fp->f_seqcount[UIO_WRITE] = 1; 2862 finit(fp, (flag & FMASK) | (fp->f_flag & FHASLOCK), DTYPE_VNODE, 2863 data, ops); 2864 } 2865 2866 int 2867 fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2868 struct file **fpp, struct filecaps *havecapsp) 2869 { 2870 struct filedescent *fde; 2871 int error; 2872 2873 FILEDESC_LOCK_ASSERT(fdp); 2874 2875 fde = fdeget_locked(fdp, fd); 2876 if (fde == NULL) { 2877 error = EBADF; 2878 goto out; 2879 } 2880 2881 #ifdef CAPABILITIES 2882 error = cap_check(cap_rights_fde_inline(fde), needrightsp); 2883 if (error != 0) 2884 goto out; 2885 #endif 2886 2887 if (havecapsp != NULL) 2888 filecaps_copy(&fde->fde_caps, havecapsp, true); 2889 2890 *fpp = fde->fde_file; 2891 2892 error = 0; 2893 out: 2894 return (error); 2895 } 2896 2897 int 2898 fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp, 2899 struct file **fpp, struct filecaps *havecapsp) 2900 { 2901 struct filedesc *fdp = td->td_proc->p_fd; 2902 int error; 2903 #ifndef CAPABILITIES 2904 error = fget_unlocked(fdp, fd, needrightsp, fpp); 2905 if (havecapsp != NULL && error == 0) 2906 filecaps_fill(havecapsp); 2907 #else 2908 struct file *fp; 2909 seqc_t seq; 2910 2911 *fpp = NULL; 2912 for (;;) { 2913 error = fget_unlocked_seq(fdp, fd, needrightsp, &fp, &seq); 2914 if (error != 0) 2915 return (error); 2916 2917 if (havecapsp != NULL) { 2918 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, 2919 havecapsp, false)) { 2920 fdrop(fp, td); 2921 goto get_locked; 2922 } 2923 } 2924 2925 if (!fd_modified(fdp, fd, seq)) 2926 break; 2927 fdrop(fp, td); 2928 } 2929 2930 *fpp = fp; 2931 return (0); 2932 2933 get_locked: 2934 FILEDESC_SLOCK(fdp); 2935 error = fget_cap_locked(fdp, fd, needrightsp, fpp, havecapsp); 2936 if (error == 0 && !fhold(*fpp)) 2937 error = EBADF; 2938 FILEDESC_SUNLOCK(fdp); 2939 #endif 2940 return (error); 2941 } 2942 2943 #ifdef CAPABILITIES 2944 int 2945 fgetvp_lookup_smr(int fd, struct nameidata *ndp, struct vnode **vpp, bool *fsearch) 2946 { 2947 const struct filedescent *fde; 2948 const struct fdescenttbl *fdt; 2949 struct filedesc *fdp; 2950 struct file *fp; 2951 struct vnode *vp; 2952 const cap_rights_t *haverights; 2953 cap_rights_t rights; 2954 seqc_t seq; 2955 2956 VFS_SMR_ASSERT_ENTERED(); 2957 2958 rights = *ndp->ni_rightsneeded; 2959 cap_rights_set_one(&rights, CAP_LOOKUP); 2960 2961 fdp = curproc->p_fd; 2962 fdt = fdp->fd_files; 2963 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 2964 return (EBADF); 2965 seq = seqc_read_notmodify(fd_seqc(fdt, fd)); 2966 fde = &fdt->fdt_ofiles[fd]; 2967 haverights = cap_rights_fde_inline(fde); 2968 fp = fde->fde_file; 2969 if (__predict_false(fp == NULL)) 2970 return (EAGAIN); 2971 if (__predict_false(cap_check_inline_transient(haverights, &rights))) 2972 return (EAGAIN); 2973 *fsearch = ((fp->f_flag & FSEARCH) != 0); 2974 vp = fp->f_vnode; 2975 if (__predict_false(vp == NULL || vp->v_type != VDIR)) { 2976 return (EAGAIN); 2977 } 2978 if (!filecaps_copy(&fde->fde_caps, &ndp->ni_filecaps, false)) { 2979 return (EAGAIN); 2980 } 2981 /* 2982 * Use an acquire barrier to force re-reading of fdt so it is 2983 * refreshed for verification. 2984 */ 2985 atomic_thread_fence_acq(); 2986 fdt = fdp->fd_files; 2987 if (__predict_false(!seqc_consistent_nomb(fd_seqc(fdt, fd), seq))) 2988 return (EAGAIN); 2989 /* 2990 * If file descriptor doesn't have all rights, 2991 * all lookups relative to it must also be 2992 * strictly relative. 2993 * 2994 * Not yet supported by fast path. 2995 */ 2996 CAP_ALL(&rights); 2997 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights, &rights) || 2998 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL || 2999 ndp->ni_filecaps.fc_nioctls != -1) { 3000 #ifdef notyet 3001 ndp->ni_lcf |= NI_LCF_STRICTRELATIVE; 3002 #else 3003 return (EAGAIN); 3004 #endif 3005 } 3006 *vpp = vp; 3007 return (0); 3008 } 3009 #else 3010 int 3011 fgetvp_lookup_smr(int fd, struct nameidata *ndp, struct vnode **vpp, bool *fsearch) 3012 { 3013 const struct fdescenttbl *fdt; 3014 struct filedesc *fdp; 3015 struct file *fp; 3016 struct vnode *vp; 3017 3018 VFS_SMR_ASSERT_ENTERED(); 3019 3020 fdp = curproc->p_fd; 3021 fdt = fdp->fd_files; 3022 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3023 return (EBADF); 3024 fp = fdt->fdt_ofiles[fd].fde_file; 3025 if (__predict_false(fp == NULL)) 3026 return (EAGAIN); 3027 *fsearch = ((fp->f_flag & FSEARCH) != 0); 3028 vp = fp->f_vnode; 3029 if (__predict_false(vp == NULL || vp->v_type != VDIR)) { 3030 return (EAGAIN); 3031 } 3032 /* 3033 * Use an acquire barrier to force re-reading of fdt so it is 3034 * refreshed for verification. 3035 */ 3036 atomic_thread_fence_acq(); 3037 fdt = fdp->fd_files; 3038 if (__predict_false(fp != fdt->fdt_ofiles[fd].fde_file)) 3039 return (EAGAIN); 3040 filecaps_fill(&ndp->ni_filecaps); 3041 *vpp = vp; 3042 return (0); 3043 } 3044 #endif 3045 3046 int 3047 fget_unlocked_seq(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 3048 struct file **fpp, seqc_t *seqp) 3049 { 3050 #ifdef CAPABILITIES 3051 const struct filedescent *fde; 3052 #endif 3053 const struct fdescenttbl *fdt; 3054 struct file *fp; 3055 #ifdef CAPABILITIES 3056 seqc_t seq; 3057 cap_rights_t haverights; 3058 int error; 3059 #endif 3060 3061 fdt = fdp->fd_files; 3062 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3063 return (EBADF); 3064 /* 3065 * Fetch the descriptor locklessly. We avoid fdrop() races by 3066 * never raising a refcount above 0. To accomplish this we have 3067 * to use a cmpset loop rather than an atomic_add. The descriptor 3068 * must be re-verified once we acquire a reference to be certain 3069 * that the identity is still correct and we did not lose a race 3070 * due to preemption. 3071 */ 3072 for (;;) { 3073 #ifdef CAPABILITIES 3074 seq = seqc_read_notmodify(fd_seqc(fdt, fd)); 3075 fde = &fdt->fdt_ofiles[fd]; 3076 haverights = *cap_rights_fde_inline(fde); 3077 fp = fde->fde_file; 3078 if (!seqc_consistent(fd_seqc(fdt, fd), seq)) 3079 continue; 3080 #else 3081 fp = fdt->fdt_ofiles[fd].fde_file; 3082 #endif 3083 if (fp == NULL) 3084 return (EBADF); 3085 #ifdef CAPABILITIES 3086 error = cap_check_inline(&haverights, needrightsp); 3087 if (error != 0) 3088 return (error); 3089 #endif 3090 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count))) { 3091 /* 3092 * Force a reload. Other thread could reallocate the 3093 * table before this fd was closed, so it is possible 3094 * that there is a stale fp pointer in cached version. 3095 */ 3096 fdt = atomic_load_ptr(&fdp->fd_files); 3097 continue; 3098 } 3099 /* 3100 * Use an acquire barrier to force re-reading of fdt so it is 3101 * refreshed for verification. 3102 */ 3103 atomic_thread_fence_acq(); 3104 fdt = fdp->fd_files; 3105 #ifdef CAPABILITIES 3106 if (seqc_consistent_nomb(fd_seqc(fdt, fd), seq)) 3107 #else 3108 if (fp == fdt->fdt_ofiles[fd].fde_file) 3109 #endif 3110 break; 3111 fdrop(fp, curthread); 3112 } 3113 *fpp = fp; 3114 if (seqp != NULL) { 3115 #ifdef CAPABILITIES 3116 *seqp = seq; 3117 #endif 3118 } 3119 return (0); 3120 } 3121 3122 /* 3123 * See the comments in fget_unlocked_seq for an explanation of how this works. 3124 * 3125 * This is a simplified variant which bails out to the aforementioned routine 3126 * if anything goes wrong. In practice this only happens when userspace is 3127 * racing with itself. 3128 */ 3129 int 3130 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 3131 struct file **fpp) 3132 { 3133 #ifdef CAPABILITIES 3134 const struct filedescent *fde; 3135 #endif 3136 const struct fdescenttbl *fdt; 3137 struct file *fp; 3138 #ifdef CAPABILITIES 3139 seqc_t seq; 3140 const cap_rights_t *haverights; 3141 #endif 3142 3143 fdt = fdp->fd_files; 3144 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) 3145 return (EBADF); 3146 #ifdef CAPABILITIES 3147 seq = seqc_read_notmodify(fd_seqc(fdt, fd)); 3148 fde = &fdt->fdt_ofiles[fd]; 3149 haverights = cap_rights_fde_inline(fde); 3150 fp = fde->fde_file; 3151 #else 3152 fp = fdt->fdt_ofiles[fd].fde_file; 3153 #endif 3154 if (__predict_false(fp == NULL)) 3155 goto out_fallback; 3156 #ifdef CAPABILITIES 3157 if (__predict_false(cap_check_inline_transient(haverights, needrightsp))) 3158 goto out_fallback; 3159 #endif 3160 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count))) 3161 goto out_fallback; 3162 3163 /* 3164 * Use an acquire barrier to force re-reading of fdt so it is 3165 * refreshed for verification. 3166 */ 3167 atomic_thread_fence_acq(); 3168 fdt = fdp->fd_files; 3169 #ifdef CAPABILITIES 3170 if (__predict_false(!seqc_consistent_nomb(fd_seqc(fdt, fd), seq))) 3171 #else 3172 if (__predict_false(fp != fdt->fdt_ofiles[fd].fde_file)) 3173 #endif 3174 goto out_fdrop; 3175 *fpp = fp; 3176 return (0); 3177 out_fdrop: 3178 fdrop(fp, curthread); 3179 out_fallback: 3180 return (fget_unlocked_seq(fdp, fd, needrightsp, fpp, NULL)); 3181 } 3182 3183 /* 3184 * Translate fd -> file when the caller guarantees the file descriptor table 3185 * can't be changed by others. 3186 * 3187 * Note this does not mean the file object itself is only visible to the caller, 3188 * merely that it wont disappear without having to be referenced. 3189 * 3190 * Must be paired with fput_only_user. 3191 */ 3192 #ifdef CAPABILITIES 3193 int 3194 fget_only_user(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 3195 struct file **fpp) 3196 { 3197 const struct filedescent *fde; 3198 const struct fdescenttbl *fdt; 3199 const cap_rights_t *haverights; 3200 struct file *fp; 3201 int error; 3202 3203 MPASS(FILEDESC_IS_ONLY_USER(fdp)); 3204 3205 if (__predict_false(fd >= fdp->fd_nfiles)) 3206 return (EBADF); 3207 3208 fdt = fdp->fd_files; 3209 fde = &fdt->fdt_ofiles[fd]; 3210 fp = fde->fde_file; 3211 if (__predict_false(fp == NULL)) 3212 return (EBADF); 3213 MPASS(refcount_load(&fp->f_count) > 0); 3214 haverights = cap_rights_fde_inline(fde); 3215 error = cap_check_inline(haverights, needrightsp); 3216 if (__predict_false(error != 0)) 3217 return (EBADF); 3218 *fpp = fp; 3219 return (0); 3220 } 3221 #else 3222 int 3223 fget_only_user(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 3224 struct file **fpp) 3225 { 3226 struct file *fp; 3227 3228 MPASS(FILEDESC_IS_ONLY_USER(fdp)); 3229 3230 if (__predict_false(fd >= fdp->fd_nfiles)) 3231 return (EBADF); 3232 3233 fp = fdp->fd_ofiles[fd].fde_file; 3234 if (__predict_false(fp == NULL)) 3235 return (EBADF); 3236 3237 MPASS(refcount_load(&fp->f_count) > 0); 3238 *fpp = fp; 3239 return (0); 3240 } 3241 #endif 3242 3243 /* 3244 * Extract the file pointer associated with the specified descriptor for the 3245 * current user process. 3246 * 3247 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 3248 * returned. 3249 * 3250 * File's rights will be checked against the capability rights mask. 3251 * 3252 * If an error occurred the non-zero error is returned and *fpp is set to 3253 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 3254 * responsible for fdrop(). 3255 */ 3256 static __inline int 3257 _fget(struct thread *td, int fd, struct file **fpp, int flags, 3258 cap_rights_t *needrightsp) 3259 { 3260 struct filedesc *fdp; 3261 struct file *fp; 3262 int error; 3263 3264 *fpp = NULL; 3265 fdp = td->td_proc->p_fd; 3266 error = fget_unlocked(fdp, fd, needrightsp, &fp); 3267 if (__predict_false(error != 0)) 3268 return (error); 3269 if (__predict_false(fp->f_ops == &badfileops)) { 3270 fdrop(fp, td); 3271 return (EBADF); 3272 } 3273 3274 /* 3275 * FREAD and FWRITE failure return EBADF as per POSIX. 3276 */ 3277 error = 0; 3278 switch (flags) { 3279 case FREAD: 3280 case FWRITE: 3281 if ((fp->f_flag & flags) == 0) 3282 error = EBADF; 3283 break; 3284 case FEXEC: 3285 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 3286 ((fp->f_flag & FWRITE) != 0)) 3287 error = EBADF; 3288 break; 3289 case 0: 3290 break; 3291 default: 3292 KASSERT(0, ("wrong flags")); 3293 } 3294 3295 if (error != 0) { 3296 fdrop(fp, td); 3297 return (error); 3298 } 3299 3300 *fpp = fp; 3301 return (0); 3302 } 3303 3304 int 3305 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 3306 { 3307 3308 return (_fget(td, fd, fpp, 0, rightsp)); 3309 } 3310 3311 int 3312 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, vm_prot_t *maxprotp, 3313 struct file **fpp) 3314 { 3315 int error; 3316 #ifndef CAPABILITIES 3317 error = _fget(td, fd, fpp, 0, rightsp); 3318 if (maxprotp != NULL) 3319 *maxprotp = VM_PROT_ALL; 3320 return (error); 3321 #else 3322 cap_rights_t fdrights; 3323 struct filedesc *fdp; 3324 struct file *fp; 3325 seqc_t seq; 3326 3327 *fpp = NULL; 3328 fdp = td->td_proc->p_fd; 3329 MPASS(cap_rights_is_set(rightsp, CAP_MMAP)); 3330 for (;;) { 3331 error = fget_unlocked_seq(fdp, fd, rightsp, &fp, &seq); 3332 if (__predict_false(error != 0)) 3333 return (error); 3334 if (__predict_false(fp->f_ops == &badfileops)) { 3335 fdrop(fp, td); 3336 return (EBADF); 3337 } 3338 if (maxprotp != NULL) 3339 fdrights = *cap_rights(fdp, fd); 3340 if (!fd_modified(fdp, fd, seq)) 3341 break; 3342 fdrop(fp, td); 3343 } 3344 3345 /* 3346 * If requested, convert capability rights to access flags. 3347 */ 3348 if (maxprotp != NULL) 3349 *maxprotp = cap_rights_to_vmprot(&fdrights); 3350 *fpp = fp; 3351 return (0); 3352 #endif 3353 } 3354 3355 int 3356 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 3357 { 3358 3359 return (_fget(td, fd, fpp, FREAD, rightsp)); 3360 } 3361 3362 int 3363 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 3364 { 3365 3366 return (_fget(td, fd, fpp, FWRITE, rightsp)); 3367 } 3368 3369 int 3370 fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp, int needfcntl, 3371 struct file **fpp) 3372 { 3373 struct filedesc *fdp = td->td_proc->p_fd; 3374 #ifndef CAPABILITIES 3375 return (fget_unlocked(fdp, fd, rightsp, fpp)); 3376 #else 3377 struct file *fp; 3378 int error; 3379 seqc_t seq; 3380 3381 *fpp = NULL; 3382 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL)); 3383 for (;;) { 3384 error = fget_unlocked_seq(fdp, fd, rightsp, &fp, &seq); 3385 if (error != 0) 3386 return (error); 3387 error = cap_fcntl_check(fdp, fd, needfcntl); 3388 if (!fd_modified(fdp, fd, seq)) 3389 break; 3390 fdrop(fp, td); 3391 } 3392 if (error != 0) { 3393 fdrop(fp, td); 3394 return (error); 3395 } 3396 *fpp = fp; 3397 return (0); 3398 #endif 3399 } 3400 3401 /* 3402 * Like fget() but loads the underlying vnode, or returns an error if the 3403 * descriptor does not represent a vnode. Note that pipes use vnodes but 3404 * never have VM objects. The returned vnode will be vref()'d. 3405 * 3406 * XXX: what about the unused flags ? 3407 */ 3408 static __inline int 3409 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 3410 struct vnode **vpp) 3411 { 3412 struct file *fp; 3413 int error; 3414 3415 *vpp = NULL; 3416 error = _fget(td, fd, &fp, flags, needrightsp); 3417 if (error != 0) 3418 return (error); 3419 if (fp->f_vnode == NULL) { 3420 error = EINVAL; 3421 } else { 3422 *vpp = fp->f_vnode; 3423 vrefact(*vpp); 3424 } 3425 fdrop(fp, td); 3426 3427 return (error); 3428 } 3429 3430 int 3431 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 3432 { 3433 3434 return (_fgetvp(td, fd, 0, rightsp, vpp)); 3435 } 3436 3437 int 3438 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 3439 struct filecaps *havecaps, struct vnode **vpp) 3440 { 3441 struct filecaps caps; 3442 struct file *fp; 3443 int error; 3444 3445 error = fget_cap(td, fd, needrightsp, &fp, &caps); 3446 if (error != 0) 3447 return (error); 3448 if (fp->f_ops == &badfileops) { 3449 error = EBADF; 3450 goto out; 3451 } 3452 if (fp->f_vnode == NULL) { 3453 error = EINVAL; 3454 goto out; 3455 } 3456 3457 *havecaps = caps; 3458 *vpp = fp->f_vnode; 3459 vrefact(*vpp); 3460 fdrop(fp, td); 3461 3462 return (0); 3463 out: 3464 filecaps_free(&caps); 3465 fdrop(fp, td); 3466 return (error); 3467 } 3468 3469 int 3470 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 3471 { 3472 3473 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 3474 } 3475 3476 int 3477 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 3478 { 3479 3480 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 3481 } 3482 3483 #ifdef notyet 3484 int 3485 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 3486 struct vnode **vpp) 3487 { 3488 3489 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 3490 } 3491 #endif 3492 3493 /* 3494 * Handle the last reference to a file being closed. 3495 * 3496 * Without the noinline attribute clang keeps inlining the func thorough this 3497 * file when fdrop is used. 3498 */ 3499 int __noinline 3500 _fdrop(struct file *fp, struct thread *td) 3501 { 3502 int error; 3503 #ifdef INVARIANTS 3504 int count; 3505 3506 count = refcount_load(&fp->f_count); 3507 if (count != 0) 3508 panic("fdrop: fp %p count %d", fp, count); 3509 #endif 3510 error = fo_close(fp, td); 3511 atomic_subtract_int(&openfiles, 1); 3512 crfree(fp->f_cred); 3513 free(fp->f_advice, M_FADVISE); 3514 uma_zfree(file_zone, fp); 3515 3516 return (error); 3517 } 3518 3519 /* 3520 * Apply an advisory lock on a file descriptor. 3521 * 3522 * Just attempt to get a record lock of the requested type on the entire file 3523 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 3524 */ 3525 #ifndef _SYS_SYSPROTO_H_ 3526 struct flock_args { 3527 int fd; 3528 int how; 3529 }; 3530 #endif 3531 /* ARGSUSED */ 3532 int 3533 sys_flock(struct thread *td, struct flock_args *uap) 3534 { 3535 struct file *fp; 3536 struct vnode *vp; 3537 struct flock lf; 3538 int error; 3539 3540 error = fget(td, uap->fd, &cap_flock_rights, &fp); 3541 if (error != 0) 3542 return (error); 3543 if (fp->f_type != DTYPE_VNODE) { 3544 fdrop(fp, td); 3545 return (EOPNOTSUPP); 3546 } 3547 3548 vp = fp->f_vnode; 3549 lf.l_whence = SEEK_SET; 3550 lf.l_start = 0; 3551 lf.l_len = 0; 3552 if (uap->how & LOCK_UN) { 3553 lf.l_type = F_UNLCK; 3554 atomic_clear_int(&fp->f_flag, FHASLOCK); 3555 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 3556 goto done2; 3557 } 3558 if (uap->how & LOCK_EX) 3559 lf.l_type = F_WRLCK; 3560 else if (uap->how & LOCK_SH) 3561 lf.l_type = F_RDLCK; 3562 else { 3563 error = EBADF; 3564 goto done2; 3565 } 3566 atomic_set_int(&fp->f_flag, FHASLOCK); 3567 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 3568 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 3569 done2: 3570 fdrop(fp, td); 3571 return (error); 3572 } 3573 /* 3574 * Duplicate the specified descriptor to a free descriptor. 3575 */ 3576 int 3577 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 3578 int openerror, int *indxp) 3579 { 3580 struct filedescent *newfde, *oldfde; 3581 struct file *fp; 3582 u_long *ioctls; 3583 int error, indx; 3584 3585 KASSERT(openerror == ENODEV || openerror == ENXIO, 3586 ("unexpected error %d in %s", openerror, __func__)); 3587 3588 /* 3589 * If the to-be-dup'd fd number is greater than the allowed number 3590 * of file descriptors, or the fd to be dup'd has already been 3591 * closed, then reject. 3592 */ 3593 FILEDESC_XLOCK(fdp); 3594 if ((fp = fget_locked(fdp, dfd)) == NULL) { 3595 FILEDESC_XUNLOCK(fdp); 3596 return (EBADF); 3597 } 3598 3599 error = fdalloc(td, 0, &indx); 3600 if (error != 0) { 3601 FILEDESC_XUNLOCK(fdp); 3602 return (error); 3603 } 3604 3605 /* 3606 * There are two cases of interest here. 3607 * 3608 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 3609 * 3610 * For ENXIO steal away the file structure from (dfd) and store it in 3611 * (indx). (dfd) is effectively closed by this operation. 3612 */ 3613 switch (openerror) { 3614 case ENODEV: 3615 /* 3616 * Check that the mode the file is being opened for is a 3617 * subset of the mode of the existing descriptor. 3618 */ 3619 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 3620 fdunused(fdp, indx); 3621 FILEDESC_XUNLOCK(fdp); 3622 return (EACCES); 3623 } 3624 if (!fhold(fp)) { 3625 fdunused(fdp, indx); 3626 FILEDESC_XUNLOCK(fdp); 3627 return (EBADF); 3628 } 3629 newfde = &fdp->fd_ofiles[indx]; 3630 oldfde = &fdp->fd_ofiles[dfd]; 3631 ioctls = filecaps_copy_prep(&oldfde->fde_caps); 3632 #ifdef CAPABILITIES 3633 seqc_write_begin(&newfde->fde_seqc); 3634 #endif 3635 memcpy(newfde, oldfde, fde_change_size); 3636 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps, 3637 ioctls); 3638 #ifdef CAPABILITIES 3639 seqc_write_end(&newfde->fde_seqc); 3640 #endif 3641 break; 3642 case ENXIO: 3643 /* 3644 * Steal away the file pointer from dfd and stuff it into indx. 3645 */ 3646 newfde = &fdp->fd_ofiles[indx]; 3647 oldfde = &fdp->fd_ofiles[dfd]; 3648 #ifdef CAPABILITIES 3649 seqc_write_begin(&newfde->fde_seqc); 3650 #endif 3651 memcpy(newfde, oldfde, fde_change_size); 3652 oldfde->fde_file = NULL; 3653 fdunused(fdp, dfd); 3654 #ifdef CAPABILITIES 3655 seqc_write_end(&newfde->fde_seqc); 3656 #endif 3657 break; 3658 } 3659 FILEDESC_XUNLOCK(fdp); 3660 *indxp = indx; 3661 return (0); 3662 } 3663 3664 /* 3665 * This sysctl determines if we will allow a process to chroot(2) if it 3666 * has a directory open: 3667 * 0: disallowed for all processes. 3668 * 1: allowed for processes that were not already chroot(2)'ed. 3669 * 2: allowed for all processes. 3670 */ 3671 3672 static int chroot_allow_open_directories = 1; 3673 3674 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW, 3675 &chroot_allow_open_directories, 0, 3676 "Allow a process to chroot(2) if it has a directory open"); 3677 3678 /* 3679 * Helper function for raised chroot(2) security function: Refuse if 3680 * any filedescriptors are open directories. 3681 */ 3682 static int 3683 chroot_refuse_vdir_fds(struct filedesc *fdp) 3684 { 3685 struct vnode *vp; 3686 struct file *fp; 3687 int fd, lastfile; 3688 3689 FILEDESC_LOCK_ASSERT(fdp); 3690 3691 lastfile = fdlastfile(fdp); 3692 for (fd = 0; fd <= lastfile; fd++) { 3693 fp = fget_locked(fdp, fd); 3694 if (fp == NULL) 3695 continue; 3696 if (fp->f_type == DTYPE_VNODE) { 3697 vp = fp->f_vnode; 3698 if (vp->v_type == VDIR) 3699 return (EPERM); 3700 } 3701 } 3702 return (0); 3703 } 3704 3705 static void 3706 pwd_fill(struct pwd *oldpwd, struct pwd *newpwd) 3707 { 3708 3709 if (newpwd->pwd_cdir == NULL && oldpwd->pwd_cdir != NULL) { 3710 vrefact(oldpwd->pwd_cdir); 3711 newpwd->pwd_cdir = oldpwd->pwd_cdir; 3712 } 3713 3714 if (newpwd->pwd_rdir == NULL && oldpwd->pwd_rdir != NULL) { 3715 vrefact(oldpwd->pwd_rdir); 3716 newpwd->pwd_rdir = oldpwd->pwd_rdir; 3717 } 3718 3719 if (newpwd->pwd_jdir == NULL && oldpwd->pwd_jdir != NULL) { 3720 vrefact(oldpwd->pwd_jdir); 3721 newpwd->pwd_jdir = oldpwd->pwd_jdir; 3722 } 3723 } 3724 3725 struct pwd * 3726 pwd_hold_pwddesc(struct pwddesc *pdp) 3727 { 3728 struct pwd *pwd; 3729 3730 PWDDESC_ASSERT_XLOCKED(pdp); 3731 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3732 if (pwd != NULL) 3733 refcount_acquire(&pwd->pwd_refcount); 3734 return (pwd); 3735 } 3736 3737 bool 3738 pwd_hold_smr(struct pwd *pwd) 3739 { 3740 3741 MPASS(pwd != NULL); 3742 if (__predict_true(refcount_acquire_if_not_zero(&pwd->pwd_refcount))) { 3743 return (true); 3744 } 3745 return (false); 3746 } 3747 3748 struct pwd * 3749 pwd_hold(struct thread *td) 3750 { 3751 struct pwddesc *pdp; 3752 struct pwd *pwd; 3753 3754 pdp = td->td_proc->p_pd; 3755 3756 vfs_smr_enter(); 3757 pwd = vfs_smr_entered_load(&pdp->pd_pwd); 3758 if (pwd_hold_smr(pwd)) { 3759 vfs_smr_exit(); 3760 return (pwd); 3761 } 3762 vfs_smr_exit(); 3763 PWDDESC_XLOCK(pdp); 3764 pwd = pwd_hold_pwddesc(pdp); 3765 MPASS(pwd != NULL); 3766 PWDDESC_XUNLOCK(pdp); 3767 return (pwd); 3768 } 3769 3770 static struct pwd * 3771 pwd_alloc(void) 3772 { 3773 struct pwd *pwd; 3774 3775 pwd = uma_zalloc_smr(pwd_zone, M_WAITOK); 3776 bzero(pwd, sizeof(*pwd)); 3777 refcount_init(&pwd->pwd_refcount, 1); 3778 return (pwd); 3779 } 3780 3781 void 3782 pwd_drop(struct pwd *pwd) 3783 { 3784 3785 if (!refcount_release(&pwd->pwd_refcount)) 3786 return; 3787 3788 if (pwd->pwd_cdir != NULL) 3789 vrele(pwd->pwd_cdir); 3790 if (pwd->pwd_rdir != NULL) 3791 vrele(pwd->pwd_rdir); 3792 if (pwd->pwd_jdir != NULL) 3793 vrele(pwd->pwd_jdir); 3794 uma_zfree_smr(pwd_zone, pwd); 3795 } 3796 3797 /* 3798 * Common routine for kern_chroot() and jail_attach(). The caller is 3799 * responsible for invoking priv_check() and mac_vnode_check_chroot() to 3800 * authorize this operation. 3801 */ 3802 int 3803 pwd_chroot(struct thread *td, struct vnode *vp) 3804 { 3805 struct pwddesc *pdp; 3806 struct filedesc *fdp; 3807 struct pwd *newpwd, *oldpwd; 3808 int error; 3809 3810 fdp = td->td_proc->p_fd; 3811 pdp = td->td_proc->p_pd; 3812 newpwd = pwd_alloc(); 3813 FILEDESC_SLOCK(fdp); 3814 PWDDESC_XLOCK(pdp); 3815 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3816 if (chroot_allow_open_directories == 0 || 3817 (chroot_allow_open_directories == 1 && 3818 oldpwd->pwd_rdir != rootvnode)) { 3819 error = chroot_refuse_vdir_fds(fdp); 3820 FILEDESC_SUNLOCK(fdp); 3821 if (error != 0) { 3822 PWDDESC_XUNLOCK(pdp); 3823 pwd_drop(newpwd); 3824 return (error); 3825 } 3826 } else { 3827 FILEDESC_SUNLOCK(fdp); 3828 } 3829 3830 vrefact(vp); 3831 newpwd->pwd_rdir = vp; 3832 if (oldpwd->pwd_jdir == NULL) { 3833 vrefact(vp); 3834 newpwd->pwd_jdir = vp; 3835 } 3836 pwd_fill(oldpwd, newpwd); 3837 pwd_set(pdp, newpwd); 3838 PWDDESC_XUNLOCK(pdp); 3839 pwd_drop(oldpwd); 3840 return (0); 3841 } 3842 3843 void 3844 pwd_chdir(struct thread *td, struct vnode *vp) 3845 { 3846 struct pwddesc *pdp; 3847 struct pwd *newpwd, *oldpwd; 3848 3849 VNPASS(vp->v_usecount > 0, vp); 3850 3851 newpwd = pwd_alloc(); 3852 pdp = td->td_proc->p_pd; 3853 PWDDESC_XLOCK(pdp); 3854 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3855 newpwd->pwd_cdir = vp; 3856 pwd_fill(oldpwd, newpwd); 3857 pwd_set(pdp, newpwd); 3858 PWDDESC_XUNLOCK(pdp); 3859 pwd_drop(oldpwd); 3860 } 3861 3862 void 3863 pwd_ensure_dirs(void) 3864 { 3865 struct pwddesc *pdp; 3866 struct pwd *oldpwd, *newpwd; 3867 3868 pdp = curproc->p_pd; 3869 PWDDESC_XLOCK(pdp); 3870 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3871 if (oldpwd->pwd_cdir != NULL && oldpwd->pwd_rdir != NULL) { 3872 PWDDESC_XUNLOCK(pdp); 3873 return; 3874 } 3875 PWDDESC_XUNLOCK(pdp); 3876 3877 newpwd = pwd_alloc(); 3878 PWDDESC_XLOCK(pdp); 3879 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3880 pwd_fill(oldpwd, newpwd); 3881 if (newpwd->pwd_cdir == NULL) { 3882 vrefact(rootvnode); 3883 newpwd->pwd_cdir = rootvnode; 3884 } 3885 if (newpwd->pwd_rdir == NULL) { 3886 vrefact(rootvnode); 3887 newpwd->pwd_rdir = rootvnode; 3888 } 3889 pwd_set(pdp, newpwd); 3890 PWDDESC_XUNLOCK(pdp); 3891 pwd_drop(oldpwd); 3892 } 3893 3894 void 3895 pwd_set_rootvnode(void) 3896 { 3897 struct pwddesc *pdp; 3898 struct pwd *oldpwd, *newpwd; 3899 3900 pdp = curproc->p_pd; 3901 3902 newpwd = pwd_alloc(); 3903 PWDDESC_XLOCK(pdp); 3904 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3905 vrefact(rootvnode); 3906 newpwd->pwd_cdir = rootvnode; 3907 vrefact(rootvnode); 3908 newpwd->pwd_rdir = rootvnode; 3909 pwd_fill(oldpwd, newpwd); 3910 pwd_set(pdp, newpwd); 3911 PWDDESC_XUNLOCK(pdp); 3912 pwd_drop(oldpwd); 3913 } 3914 3915 /* 3916 * Scan all active processes and prisons to see if any of them have a current 3917 * or root directory of `olddp'. If so, replace them with the new mount point. 3918 */ 3919 void 3920 mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 3921 { 3922 struct pwddesc *pdp; 3923 struct pwd *newpwd, *oldpwd; 3924 struct prison *pr; 3925 struct proc *p; 3926 int nrele; 3927 3928 if (vrefcnt(olddp) == 1) 3929 return; 3930 nrele = 0; 3931 newpwd = pwd_alloc(); 3932 sx_slock(&allproc_lock); 3933 FOREACH_PROC_IN_SYSTEM(p) { 3934 PROC_LOCK(p); 3935 pdp = pdhold(p); 3936 PROC_UNLOCK(p); 3937 if (pdp == NULL) 3938 continue; 3939 PWDDESC_XLOCK(pdp); 3940 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 3941 if (oldpwd == NULL || 3942 (oldpwd->pwd_cdir != olddp && 3943 oldpwd->pwd_rdir != olddp && 3944 oldpwd->pwd_jdir != olddp)) { 3945 PWDDESC_XUNLOCK(pdp); 3946 pddrop(pdp); 3947 continue; 3948 } 3949 if (oldpwd->pwd_cdir == olddp) { 3950 vrefact(newdp); 3951 newpwd->pwd_cdir = newdp; 3952 } 3953 if (oldpwd->pwd_rdir == olddp) { 3954 vrefact(newdp); 3955 newpwd->pwd_rdir = newdp; 3956 } 3957 if (oldpwd->pwd_jdir == olddp) { 3958 vrefact(newdp); 3959 newpwd->pwd_jdir = newdp; 3960 } 3961 pwd_fill(oldpwd, newpwd); 3962 pwd_set(pdp, newpwd); 3963 PWDDESC_XUNLOCK(pdp); 3964 pwd_drop(oldpwd); 3965 pddrop(pdp); 3966 newpwd = pwd_alloc(); 3967 } 3968 sx_sunlock(&allproc_lock); 3969 pwd_drop(newpwd); 3970 if (rootvnode == olddp) { 3971 vrefact(newdp); 3972 rootvnode = newdp; 3973 nrele++; 3974 } 3975 mtx_lock(&prison0.pr_mtx); 3976 if (prison0.pr_root == olddp) { 3977 vrefact(newdp); 3978 prison0.pr_root = newdp; 3979 nrele++; 3980 } 3981 mtx_unlock(&prison0.pr_mtx); 3982 sx_slock(&allprison_lock); 3983 TAILQ_FOREACH(pr, &allprison, pr_list) { 3984 mtx_lock(&pr->pr_mtx); 3985 if (pr->pr_root == olddp) { 3986 vrefact(newdp); 3987 pr->pr_root = newdp; 3988 nrele++; 3989 } 3990 mtx_unlock(&pr->pr_mtx); 3991 } 3992 sx_sunlock(&allprison_lock); 3993 while (nrele--) 3994 vrele(olddp); 3995 } 3996 3997 struct filedesc_to_leader * 3998 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 3999 { 4000 struct filedesc_to_leader *fdtol; 4001 4002 fdtol = malloc(sizeof(struct filedesc_to_leader), 4003 M_FILEDESC_TO_LEADER, M_WAITOK); 4004 fdtol->fdl_refcount = 1; 4005 fdtol->fdl_holdcount = 0; 4006 fdtol->fdl_wakeup = 0; 4007 fdtol->fdl_leader = leader; 4008 if (old != NULL) { 4009 FILEDESC_XLOCK(fdp); 4010 fdtol->fdl_next = old->fdl_next; 4011 fdtol->fdl_prev = old; 4012 old->fdl_next = fdtol; 4013 fdtol->fdl_next->fdl_prev = fdtol; 4014 FILEDESC_XUNLOCK(fdp); 4015 } else { 4016 fdtol->fdl_next = fdtol; 4017 fdtol->fdl_prev = fdtol; 4018 } 4019 return (fdtol); 4020 } 4021 4022 static int 4023 sysctl_kern_proc_nfds(SYSCTL_HANDLER_ARGS) 4024 { 4025 NDSLOTTYPE *map; 4026 struct filedesc *fdp; 4027 int count, off, minoff; 4028 4029 if (*(int *)arg1 != 0) 4030 return (EINVAL); 4031 4032 fdp = curproc->p_fd; 4033 count = 0; 4034 FILEDESC_SLOCK(fdp); 4035 map = fdp->fd_map; 4036 off = NDSLOT(fdp->fd_nfiles - 1); 4037 for (minoff = NDSLOT(0); off >= minoff; --off) 4038 count += bitcountl(map[off]); 4039 FILEDESC_SUNLOCK(fdp); 4040 4041 return (SYSCTL_OUT(req, &count, sizeof(count))); 4042 } 4043 4044 static SYSCTL_NODE(_kern_proc, KERN_PROC_NFDS, nfds, 4045 CTLFLAG_RD|CTLFLAG_CAPRD|CTLFLAG_MPSAFE, sysctl_kern_proc_nfds, 4046 "Number of open file descriptors"); 4047 4048 /* 4049 * Get file structures globally. 4050 */ 4051 static int 4052 sysctl_kern_file(SYSCTL_HANDLER_ARGS) 4053 { 4054 struct xfile xf; 4055 struct filedesc *fdp; 4056 struct file *fp; 4057 struct proc *p; 4058 int error, n, lastfile; 4059 4060 error = sysctl_wire_old_buffer(req, 0); 4061 if (error != 0) 4062 return (error); 4063 if (req->oldptr == NULL) { 4064 n = 0; 4065 sx_slock(&allproc_lock); 4066 FOREACH_PROC_IN_SYSTEM(p) { 4067 PROC_LOCK(p); 4068 if (p->p_state == PRS_NEW) { 4069 PROC_UNLOCK(p); 4070 continue; 4071 } 4072 fdp = fdhold(p); 4073 PROC_UNLOCK(p); 4074 if (fdp == NULL) 4075 continue; 4076 /* overestimates sparse tables. */ 4077 n += fdp->fd_nfiles; 4078 fddrop(fdp); 4079 } 4080 sx_sunlock(&allproc_lock); 4081 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 4082 } 4083 error = 0; 4084 bzero(&xf, sizeof(xf)); 4085 xf.xf_size = sizeof(xf); 4086 sx_slock(&allproc_lock); 4087 FOREACH_PROC_IN_SYSTEM(p) { 4088 PROC_LOCK(p); 4089 if (p->p_state == PRS_NEW) { 4090 PROC_UNLOCK(p); 4091 continue; 4092 } 4093 if (p_cansee(req->td, p) != 0) { 4094 PROC_UNLOCK(p); 4095 continue; 4096 } 4097 xf.xf_pid = p->p_pid; 4098 xf.xf_uid = p->p_ucred->cr_uid; 4099 fdp = fdhold(p); 4100 PROC_UNLOCK(p); 4101 if (fdp == NULL) 4102 continue; 4103 FILEDESC_SLOCK(fdp); 4104 lastfile = fdlastfile(fdp); 4105 for (n = 0; refcount_load(&fdp->fd_refcnt) > 0 && n <= lastfile; 4106 n++) { 4107 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 4108 continue; 4109 xf.xf_fd = n; 4110 xf.xf_file = (uintptr_t)fp; 4111 xf.xf_data = (uintptr_t)fp->f_data; 4112 xf.xf_vnode = (uintptr_t)fp->f_vnode; 4113 xf.xf_type = (uintptr_t)fp->f_type; 4114 xf.xf_count = refcount_load(&fp->f_count); 4115 xf.xf_msgcount = 0; 4116 xf.xf_offset = foffset_get(fp); 4117 xf.xf_flag = fp->f_flag; 4118 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 4119 if (error) 4120 break; 4121 } 4122 FILEDESC_SUNLOCK(fdp); 4123 fddrop(fdp); 4124 if (error) 4125 break; 4126 } 4127 sx_sunlock(&allproc_lock); 4128 return (error); 4129 } 4130 4131 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 4132 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 4133 4134 #ifdef KINFO_FILE_SIZE 4135 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 4136 #endif 4137 4138 static int 4139 xlate_fflags(int fflags) 4140 { 4141 static const struct { 4142 int fflag; 4143 int kf_fflag; 4144 } fflags_table[] = { 4145 { FAPPEND, KF_FLAG_APPEND }, 4146 { FASYNC, KF_FLAG_ASYNC }, 4147 { FFSYNC, KF_FLAG_FSYNC }, 4148 { FHASLOCK, KF_FLAG_HASLOCK }, 4149 { FNONBLOCK, KF_FLAG_NONBLOCK }, 4150 { FREAD, KF_FLAG_READ }, 4151 { FWRITE, KF_FLAG_WRITE }, 4152 { O_CREAT, KF_FLAG_CREAT }, 4153 { O_DIRECT, KF_FLAG_DIRECT }, 4154 { O_EXCL, KF_FLAG_EXCL }, 4155 { O_EXEC, KF_FLAG_EXEC }, 4156 { O_EXLOCK, KF_FLAG_EXLOCK }, 4157 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 4158 { O_SHLOCK, KF_FLAG_SHLOCK }, 4159 { O_TRUNC, KF_FLAG_TRUNC } 4160 }; 4161 unsigned int i; 4162 int kflags; 4163 4164 kflags = 0; 4165 for (i = 0; i < nitems(fflags_table); i++) 4166 if (fflags & fflags_table[i].fflag) 4167 kflags |= fflags_table[i].kf_fflag; 4168 return (kflags); 4169 } 4170 4171 /* Trim unused data from kf_path by truncating the structure size. */ 4172 void 4173 pack_kinfo(struct kinfo_file *kif) 4174 { 4175 4176 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 4177 strlen(kif->kf_path) + 1; 4178 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 4179 } 4180 4181 static void 4182 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp, 4183 struct kinfo_file *kif, struct filedesc *fdp, int flags) 4184 { 4185 int error; 4186 4187 bzero(kif, sizeof(*kif)); 4188 4189 /* Set a default type to allow for empty fill_kinfo() methods. */ 4190 kif->kf_type = KF_TYPE_UNKNOWN; 4191 kif->kf_flags = xlate_fflags(fp->f_flag); 4192 if (rightsp != NULL) 4193 kif->kf_cap_rights = *rightsp; 4194 else 4195 cap_rights_init_zero(&kif->kf_cap_rights); 4196 kif->kf_fd = fd; 4197 kif->kf_ref_count = refcount_load(&fp->f_count); 4198 kif->kf_offset = foffset_get(fp); 4199 4200 /* 4201 * This may drop the filedesc lock, so the 'fp' cannot be 4202 * accessed after this call. 4203 */ 4204 error = fo_fill_kinfo(fp, kif, fdp); 4205 if (error == 0) 4206 kif->kf_status |= KF_ATTR_VALID; 4207 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 4208 pack_kinfo(kif); 4209 else 4210 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 4211 } 4212 4213 static void 4214 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags, 4215 struct kinfo_file *kif, int flags) 4216 { 4217 int error; 4218 4219 bzero(kif, sizeof(*kif)); 4220 4221 kif->kf_type = KF_TYPE_VNODE; 4222 error = vn_fill_kinfo_vnode(vp, kif); 4223 if (error == 0) 4224 kif->kf_status |= KF_ATTR_VALID; 4225 kif->kf_flags = xlate_fflags(fflags); 4226 cap_rights_init_zero(&kif->kf_cap_rights); 4227 kif->kf_fd = fd; 4228 kif->kf_ref_count = -1; 4229 kif->kf_offset = -1; 4230 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0) 4231 pack_kinfo(kif); 4232 else 4233 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t)); 4234 vrele(vp); 4235 } 4236 4237 struct export_fd_buf { 4238 struct filedesc *fdp; 4239 struct pwddesc *pdp; 4240 struct sbuf *sb; 4241 ssize_t remainder; 4242 struct kinfo_file kif; 4243 int flags; 4244 }; 4245 4246 static int 4247 export_kinfo_to_sb(struct export_fd_buf *efbuf) 4248 { 4249 struct kinfo_file *kif; 4250 4251 kif = &efbuf->kif; 4252 if (efbuf->remainder != -1) { 4253 if (efbuf->remainder < kif->kf_structsize) { 4254 /* Terminate export. */ 4255 efbuf->remainder = 0; 4256 return (0); 4257 } 4258 efbuf->remainder -= kif->kf_structsize; 4259 } 4260 return (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) == 0 ? 0 : ENOMEM); 4261 } 4262 4263 static int 4264 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp, 4265 struct export_fd_buf *efbuf) 4266 { 4267 int error; 4268 4269 if (efbuf->remainder == 0) 4270 return (0); 4271 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp, 4272 efbuf->flags); 4273 FILEDESC_SUNLOCK(efbuf->fdp); 4274 error = export_kinfo_to_sb(efbuf); 4275 FILEDESC_SLOCK(efbuf->fdp); 4276 return (error); 4277 } 4278 4279 static int 4280 export_vnode_to_sb(struct vnode *vp, int fd, int fflags, 4281 struct export_fd_buf *efbuf) 4282 { 4283 int error; 4284 4285 if (efbuf->remainder == 0) 4286 return (0); 4287 if (efbuf->pdp != NULL) 4288 PWDDESC_XUNLOCK(efbuf->pdp); 4289 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif, efbuf->flags); 4290 error = export_kinfo_to_sb(efbuf); 4291 if (efbuf->pdp != NULL) 4292 PWDDESC_XLOCK(efbuf->pdp); 4293 return (error); 4294 } 4295 4296 /* 4297 * Store a process file descriptor information to sbuf. 4298 * 4299 * Takes a locked proc as argument, and returns with the proc unlocked. 4300 */ 4301 int 4302 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen, 4303 int flags) 4304 { 4305 struct file *fp; 4306 struct filedesc *fdp; 4307 struct pwddesc *pdp; 4308 struct export_fd_buf *efbuf; 4309 struct vnode *cttyvp, *textvp, *tracevp; 4310 struct pwd *pwd; 4311 int error, i, lastfile; 4312 cap_rights_t rights; 4313 4314 PROC_LOCK_ASSERT(p, MA_OWNED); 4315 4316 /* ktrace vnode */ 4317 tracevp = p->p_tracevp; 4318 if (tracevp != NULL) 4319 vrefact(tracevp); 4320 /* text vnode */ 4321 textvp = p->p_textvp; 4322 if (textvp != NULL) 4323 vrefact(textvp); 4324 /* Controlling tty. */ 4325 cttyvp = NULL; 4326 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 4327 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 4328 if (cttyvp != NULL) 4329 vrefact(cttyvp); 4330 } 4331 fdp = fdhold(p); 4332 pdp = pdhold(p); 4333 PROC_UNLOCK(p); 4334 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 4335 efbuf->fdp = NULL; 4336 efbuf->pdp = NULL; 4337 efbuf->sb = sb; 4338 efbuf->remainder = maxlen; 4339 efbuf->flags = flags; 4340 if (tracevp != NULL) 4341 export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE, FREAD | FWRITE, 4342 efbuf); 4343 if (textvp != NULL) 4344 export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD, efbuf); 4345 if (cttyvp != NULL) 4346 export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY, FREAD | FWRITE, 4347 efbuf); 4348 error = 0; 4349 if (pdp == NULL || fdp == NULL) 4350 goto fail; 4351 efbuf->fdp = fdp; 4352 efbuf->pdp = pdp; 4353 PWDDESC_XLOCK(pdp); 4354 pwd = pwd_hold_pwddesc(pdp); 4355 if (pwd != NULL) { 4356 /* working directory */ 4357 if (pwd->pwd_cdir != NULL) { 4358 vrefact(pwd->pwd_cdir); 4359 export_vnode_to_sb(pwd->pwd_cdir, KF_FD_TYPE_CWD, FREAD, efbuf); 4360 } 4361 /* root directory */ 4362 if (pwd->pwd_rdir != NULL) { 4363 vrefact(pwd->pwd_rdir); 4364 export_vnode_to_sb(pwd->pwd_rdir, KF_FD_TYPE_ROOT, FREAD, efbuf); 4365 } 4366 /* jail directory */ 4367 if (pwd->pwd_jdir != NULL) { 4368 vrefact(pwd->pwd_jdir); 4369 export_vnode_to_sb(pwd->pwd_jdir, KF_FD_TYPE_JAIL, FREAD, efbuf); 4370 } 4371 } 4372 PWDDESC_XUNLOCK(pdp); 4373 if (pwd != NULL) 4374 pwd_drop(pwd); 4375 FILEDESC_SLOCK(fdp); 4376 lastfile = fdlastfile(fdp); 4377 for (i = 0; refcount_load(&fdp->fd_refcnt) > 0 && i <= lastfile; i++) { 4378 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 4379 continue; 4380 #ifdef CAPABILITIES 4381 rights = *cap_rights(fdp, i); 4382 #else /* !CAPABILITIES */ 4383 rights = cap_no_rights; 4384 #endif 4385 /* 4386 * Create sysctl entry. It is OK to drop the filedesc 4387 * lock inside of export_file_to_sb() as we will 4388 * re-validate and re-evaluate its properties when the 4389 * loop continues. 4390 */ 4391 error = export_file_to_sb(fp, i, &rights, efbuf); 4392 if (error != 0 || efbuf->remainder == 0) 4393 break; 4394 } 4395 FILEDESC_SUNLOCK(fdp); 4396 fail: 4397 if (fdp != NULL) 4398 fddrop(fdp); 4399 if (pdp != NULL) 4400 pddrop(pdp); 4401 free(efbuf, M_TEMP); 4402 return (error); 4403 } 4404 4405 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 4406 4407 /* 4408 * Get per-process file descriptors for use by procstat(1), et al. 4409 */ 4410 static int 4411 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 4412 { 4413 struct sbuf sb; 4414 struct proc *p; 4415 ssize_t maxlen; 4416 int error, error2, *name; 4417 4418 name = (int *)arg1; 4419 4420 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 4421 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 4422 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 4423 if (error != 0) { 4424 sbuf_delete(&sb); 4425 return (error); 4426 } 4427 maxlen = req->oldptr != NULL ? req->oldlen : -1; 4428 error = kern_proc_filedesc_out(p, &sb, maxlen, 4429 KERN_FILEDESC_PACK_KINFO); 4430 error2 = sbuf_finish(&sb); 4431 sbuf_delete(&sb); 4432 return (error != 0 ? error : error2); 4433 } 4434 4435 #ifdef COMPAT_FREEBSD7 4436 #ifdef KINFO_OFILE_SIZE 4437 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 4438 #endif 4439 4440 static void 4441 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif) 4442 { 4443 4444 okif->kf_structsize = sizeof(*okif); 4445 okif->kf_type = kif->kf_type; 4446 okif->kf_fd = kif->kf_fd; 4447 okif->kf_ref_count = kif->kf_ref_count; 4448 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE | 4449 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK | 4450 KF_FLAG_DIRECT | KF_FLAG_HASLOCK); 4451 okif->kf_offset = kif->kf_offset; 4452 if (kif->kf_type == KF_TYPE_VNODE) 4453 okif->kf_vnode_type = kif->kf_un.kf_file.kf_file_type; 4454 else 4455 okif->kf_vnode_type = KF_VTYPE_VNON; 4456 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path)); 4457 if (kif->kf_type == KF_TYPE_SOCKET) { 4458 okif->kf_sock_domain = kif->kf_un.kf_sock.kf_sock_domain0; 4459 okif->kf_sock_type = kif->kf_un.kf_sock.kf_sock_type0; 4460 okif->kf_sock_protocol = kif->kf_un.kf_sock.kf_sock_protocol0; 4461 okif->kf_sa_local = kif->kf_un.kf_sock.kf_sa_local; 4462 okif->kf_sa_peer = kif->kf_un.kf_sock.kf_sa_peer; 4463 } else { 4464 okif->kf_sa_local.ss_family = AF_UNSPEC; 4465 okif->kf_sa_peer.ss_family = AF_UNSPEC; 4466 } 4467 } 4468 4469 static int 4470 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif, 4471 struct kinfo_ofile *okif, struct pwddesc *pdp, struct sysctl_req *req) 4472 { 4473 int error; 4474 4475 vrefact(vp); 4476 PWDDESC_XUNLOCK(pdp); 4477 export_vnode_to_kinfo(vp, type, 0, kif, KERN_FILEDESC_PACK_KINFO); 4478 kinfo_to_okinfo(kif, okif); 4479 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 4480 PWDDESC_XLOCK(pdp); 4481 return (error); 4482 } 4483 4484 /* 4485 * Get per-process file descriptors for use by procstat(1), et al. 4486 */ 4487 static int 4488 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 4489 { 4490 struct kinfo_ofile *okif; 4491 struct kinfo_file *kif; 4492 struct filedesc *fdp; 4493 struct pwddesc *pdp; 4494 struct pwd *pwd; 4495 int error, i, lastfile, *name; 4496 struct file *fp; 4497 struct proc *p; 4498 4499 name = (int *)arg1; 4500 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 4501 if (error != 0) 4502 return (error); 4503 fdp = fdhold(p); 4504 if (fdp != NULL) 4505 pdp = pdhold(p); 4506 PROC_UNLOCK(p); 4507 if (fdp == NULL || pdp == NULL) { 4508 if (fdp != NULL) 4509 fddrop(fdp); 4510 return (ENOENT); 4511 } 4512 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 4513 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK); 4514 PWDDESC_XLOCK(pdp); 4515 pwd = pwd_hold_pwddesc(pdp); 4516 if (pwd != NULL) { 4517 if (pwd->pwd_cdir != NULL) 4518 export_vnode_for_osysctl(pwd->pwd_cdir, KF_FD_TYPE_CWD, kif, 4519 okif, pdp, req); 4520 if (pwd->pwd_rdir != NULL) 4521 export_vnode_for_osysctl(pwd->pwd_rdir, KF_FD_TYPE_ROOT, kif, 4522 okif, pdp, req); 4523 if (pwd->pwd_jdir != NULL) 4524 export_vnode_for_osysctl(pwd->pwd_jdir, KF_FD_TYPE_JAIL, kif, 4525 okif, pdp, req); 4526 } 4527 PWDDESC_XUNLOCK(pdp); 4528 if (pwd != NULL) 4529 pwd_drop(pwd); 4530 FILEDESC_SLOCK(fdp); 4531 lastfile = fdlastfile(fdp); 4532 for (i = 0; refcount_load(&fdp->fd_refcnt) > 0 && i <= lastfile; i++) { 4533 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 4534 continue; 4535 export_file_to_kinfo(fp, i, NULL, kif, fdp, 4536 KERN_FILEDESC_PACK_KINFO); 4537 FILEDESC_SUNLOCK(fdp); 4538 kinfo_to_okinfo(kif, okif); 4539 error = SYSCTL_OUT(req, okif, sizeof(*okif)); 4540 FILEDESC_SLOCK(fdp); 4541 if (error) 4542 break; 4543 } 4544 FILEDESC_SUNLOCK(fdp); 4545 fddrop(fdp); 4546 pddrop(pdp); 4547 free(kif, M_TEMP); 4548 free(okif, M_TEMP); 4549 return (0); 4550 } 4551 4552 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 4553 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 4554 "Process ofiledesc entries"); 4555 #endif /* COMPAT_FREEBSD7 */ 4556 4557 int 4558 vntype_to_kinfo(int vtype) 4559 { 4560 struct { 4561 int vtype; 4562 int kf_vtype; 4563 } vtypes_table[] = { 4564 { VBAD, KF_VTYPE_VBAD }, 4565 { VBLK, KF_VTYPE_VBLK }, 4566 { VCHR, KF_VTYPE_VCHR }, 4567 { VDIR, KF_VTYPE_VDIR }, 4568 { VFIFO, KF_VTYPE_VFIFO }, 4569 { VLNK, KF_VTYPE_VLNK }, 4570 { VNON, KF_VTYPE_VNON }, 4571 { VREG, KF_VTYPE_VREG }, 4572 { VSOCK, KF_VTYPE_VSOCK } 4573 }; 4574 unsigned int i; 4575 4576 /* 4577 * Perform vtype translation. 4578 */ 4579 for (i = 0; i < nitems(vtypes_table); i++) 4580 if (vtypes_table[i].vtype == vtype) 4581 return (vtypes_table[i].kf_vtype); 4582 4583 return (KF_VTYPE_UNKNOWN); 4584 } 4585 4586 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 4587 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 4588 "Process filedesc entries"); 4589 4590 /* 4591 * Store a process current working directory information to sbuf. 4592 * 4593 * Takes a locked proc as argument, and returns with the proc unlocked. 4594 */ 4595 int 4596 kern_proc_cwd_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 4597 { 4598 struct pwddesc *pdp; 4599 struct pwd *pwd; 4600 struct export_fd_buf *efbuf; 4601 struct vnode *cdir; 4602 int error; 4603 4604 PROC_LOCK_ASSERT(p, MA_OWNED); 4605 4606 pdp = pdhold(p); 4607 PROC_UNLOCK(p); 4608 if (pdp == NULL) 4609 return (EINVAL); 4610 4611 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 4612 efbuf->pdp = pdp; 4613 efbuf->sb = sb; 4614 efbuf->remainder = maxlen; 4615 4616 PWDDESC_XLOCK(pdp); 4617 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp); 4618 cdir = pwd->pwd_cdir; 4619 if (cdir == NULL) { 4620 error = EINVAL; 4621 } else { 4622 vrefact(cdir); 4623 error = export_vnode_to_sb(cdir, KF_FD_TYPE_CWD, FREAD, efbuf); 4624 } 4625 PWDDESC_XUNLOCK(pdp); 4626 pddrop(pdp); 4627 free(efbuf, M_TEMP); 4628 return (error); 4629 } 4630 4631 /* 4632 * Get per-process current working directory. 4633 */ 4634 static int 4635 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS) 4636 { 4637 struct sbuf sb; 4638 struct proc *p; 4639 ssize_t maxlen; 4640 int error, error2, *name; 4641 4642 name = (int *)arg1; 4643 4644 sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file), req); 4645 sbuf_clear_flags(&sb, SBUF_INCLUDENUL); 4646 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 4647 if (error != 0) { 4648 sbuf_delete(&sb); 4649 return (error); 4650 } 4651 maxlen = req->oldptr != NULL ? req->oldlen : -1; 4652 error = kern_proc_cwd_out(p, &sb, maxlen); 4653 error2 = sbuf_finish(&sb); 4654 sbuf_delete(&sb); 4655 return (error != 0 ? error : error2); 4656 } 4657 4658 static SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD|CTLFLAG_MPSAFE, 4659 sysctl_kern_proc_cwd, "Process current working directory"); 4660 4661 #ifdef DDB 4662 /* 4663 * For the purposes of debugging, generate a human-readable string for the 4664 * file type. 4665 */ 4666 static const char * 4667 file_type_to_name(short type) 4668 { 4669 4670 switch (type) { 4671 case 0: 4672 return ("zero"); 4673 case DTYPE_VNODE: 4674 return ("vnode"); 4675 case DTYPE_SOCKET: 4676 return ("socket"); 4677 case DTYPE_PIPE: 4678 return ("pipe"); 4679 case DTYPE_FIFO: 4680 return ("fifo"); 4681 case DTYPE_KQUEUE: 4682 return ("kqueue"); 4683 case DTYPE_CRYPTO: 4684 return ("crypto"); 4685 case DTYPE_MQUEUE: 4686 return ("mqueue"); 4687 case DTYPE_SHM: 4688 return ("shm"); 4689 case DTYPE_SEM: 4690 return ("ksem"); 4691 case DTYPE_PTS: 4692 return ("pts"); 4693 case DTYPE_DEV: 4694 return ("dev"); 4695 case DTYPE_PROCDESC: 4696 return ("proc"); 4697 case DTYPE_EVENTFD: 4698 return ("eventfd"); 4699 case DTYPE_LINUXTFD: 4700 return ("ltimer"); 4701 default: 4702 return ("unkn"); 4703 } 4704 } 4705 4706 /* 4707 * For the purposes of debugging, identify a process (if any, perhaps one of 4708 * many) that references the passed file in its file descriptor array. Return 4709 * NULL if none. 4710 */ 4711 static struct proc * 4712 file_to_first_proc(struct file *fp) 4713 { 4714 struct filedesc *fdp; 4715 struct proc *p; 4716 int n; 4717 4718 FOREACH_PROC_IN_SYSTEM(p) { 4719 if (p->p_state == PRS_NEW) 4720 continue; 4721 fdp = p->p_fd; 4722 if (fdp == NULL) 4723 continue; 4724 for (n = 0; n < fdp->fd_nfiles; n++) { 4725 if (fp == fdp->fd_ofiles[n].fde_file) 4726 return (p); 4727 } 4728 } 4729 return (NULL); 4730 } 4731 4732 static void 4733 db_print_file(struct file *fp, int header) 4734 { 4735 #define XPTRWIDTH ((int)howmany(sizeof(void *) * NBBY, 4)) 4736 struct proc *p; 4737 4738 if (header) 4739 db_printf("%*s %6s %*s %8s %4s %5s %6s %*s %5s %s\n", 4740 XPTRWIDTH, "File", "Type", XPTRWIDTH, "Data", "Flag", 4741 "GCFl", "Count", "MCount", XPTRWIDTH, "Vnode", "FPID", 4742 "FCmd"); 4743 p = file_to_first_proc(fp); 4744 db_printf("%*p %6s %*p %08x %04x %5d %6d %*p %5d %s\n", XPTRWIDTH, 4745 fp, file_type_to_name(fp->f_type), XPTRWIDTH, fp->f_data, 4746 fp->f_flag, 0, refcount_load(&fp->f_count), 0, XPTRWIDTH, fp->f_vnode, 4747 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 4748 4749 #undef XPTRWIDTH 4750 } 4751 4752 DB_SHOW_COMMAND(file, db_show_file) 4753 { 4754 struct file *fp; 4755 4756 if (!have_addr) { 4757 db_printf("usage: show file <addr>\n"); 4758 return; 4759 } 4760 fp = (struct file *)addr; 4761 db_print_file(fp, 1); 4762 } 4763 4764 DB_SHOW_COMMAND(files, db_show_files) 4765 { 4766 struct filedesc *fdp; 4767 struct file *fp; 4768 struct proc *p; 4769 int header; 4770 int n; 4771 4772 header = 1; 4773 FOREACH_PROC_IN_SYSTEM(p) { 4774 if (p->p_state == PRS_NEW) 4775 continue; 4776 if ((fdp = p->p_fd) == NULL) 4777 continue; 4778 for (n = 0; n < fdp->fd_nfiles; ++n) { 4779 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 4780 continue; 4781 db_print_file(fp, header); 4782 header = 0; 4783 } 4784 } 4785 } 4786 #endif 4787 4788 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 4789 &maxfilesperproc, 0, "Maximum files allowed open per process"); 4790 4791 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 4792 &maxfiles, 0, "Maximum number of files"); 4793 4794 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 4795 &openfiles, 0, "System-wide number of open files"); 4796 4797 /* ARGSUSED*/ 4798 static void 4799 filelistinit(void *dummy) 4800 { 4801 4802 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 4803 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 4804 filedesc0_zone = uma_zcreate("filedesc0", sizeof(struct filedesc0), 4805 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 4806 pwd_zone = uma_zcreate("PWD", sizeof(struct pwd), NULL, NULL, 4807 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_SMR); 4808 /* 4809 * XXXMJG this is a temporary hack due to boot ordering issues against 4810 * the vnode zone. 4811 */ 4812 vfs_smr = uma_zone_get_smr(pwd_zone); 4813 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 4814 } 4815 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 4816 4817 /*-------------------------------------------------------------------*/ 4818 4819 static int 4820 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 4821 int flags, struct thread *td) 4822 { 4823 4824 return (EBADF); 4825 } 4826 4827 static int 4828 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 4829 struct thread *td) 4830 { 4831 4832 return (EINVAL); 4833 } 4834 4835 static int 4836 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 4837 struct thread *td) 4838 { 4839 4840 return (EBADF); 4841 } 4842 4843 static int 4844 badfo_poll(struct file *fp, int events, struct ucred *active_cred, 4845 struct thread *td) 4846 { 4847 4848 return (0); 4849 } 4850 4851 static int 4852 badfo_kqfilter(struct file *fp, struct knote *kn) 4853 { 4854 4855 return (EBADF); 4856 } 4857 4858 static int 4859 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 4860 struct thread *td) 4861 { 4862 4863 return (EBADF); 4864 } 4865 4866 static int 4867 badfo_close(struct file *fp, struct thread *td) 4868 { 4869 4870 return (0); 4871 } 4872 4873 static int 4874 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 4875 struct thread *td) 4876 { 4877 4878 return (EBADF); 4879 } 4880 4881 static int 4882 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4883 struct thread *td) 4884 { 4885 4886 return (EBADF); 4887 } 4888 4889 static int 4890 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4891 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4892 struct thread *td) 4893 { 4894 4895 return (EBADF); 4896 } 4897 4898 static int 4899 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp) 4900 { 4901 4902 return (0); 4903 } 4904 4905 struct fileops badfileops = { 4906 .fo_read = badfo_readwrite, 4907 .fo_write = badfo_readwrite, 4908 .fo_truncate = badfo_truncate, 4909 .fo_ioctl = badfo_ioctl, 4910 .fo_poll = badfo_poll, 4911 .fo_kqfilter = badfo_kqfilter, 4912 .fo_stat = badfo_stat, 4913 .fo_close = badfo_close, 4914 .fo_chmod = badfo_chmod, 4915 .fo_chown = badfo_chown, 4916 .fo_sendfile = badfo_sendfile, 4917 .fo_fill_kinfo = badfo_fill_kinfo, 4918 }; 4919 4920 int 4921 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred, 4922 int flags, struct thread *td) 4923 { 4924 4925 return (EOPNOTSUPP); 4926 } 4927 4928 int 4929 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 4930 struct thread *td) 4931 { 4932 4933 return (EINVAL); 4934 } 4935 4936 int 4937 invfo_ioctl(struct file *fp, u_long com, void *data, 4938 struct ucred *active_cred, struct thread *td) 4939 { 4940 4941 return (ENOTTY); 4942 } 4943 4944 int 4945 invfo_poll(struct file *fp, int events, struct ucred *active_cred, 4946 struct thread *td) 4947 { 4948 4949 return (poll_no_poll(events)); 4950 } 4951 4952 int 4953 invfo_kqfilter(struct file *fp, struct knote *kn) 4954 { 4955 4956 return (EINVAL); 4957 } 4958 4959 int 4960 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 4961 struct thread *td) 4962 { 4963 4964 return (EINVAL); 4965 } 4966 4967 int 4968 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4969 struct thread *td) 4970 { 4971 4972 return (EINVAL); 4973 } 4974 4975 int 4976 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4977 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4978 struct thread *td) 4979 { 4980 4981 return (EINVAL); 4982 } 4983 4984 /*-------------------------------------------------------------------*/ 4985 4986 /* 4987 * File Descriptor pseudo-device driver (/dev/fd/). 4988 * 4989 * Opening minor device N dup()s the file (if any) connected to file 4990 * descriptor N belonging to the calling process. Note that this driver 4991 * consists of only the ``open()'' routine, because all subsequent 4992 * references to this file will be direct to the other driver. 4993 * 4994 * XXX: we could give this one a cloning event handler if necessary. 4995 */ 4996 4997 /* ARGSUSED */ 4998 static int 4999 fdopen(struct cdev *dev, int mode, int type, struct thread *td) 5000 { 5001 5002 /* 5003 * XXX Kludge: set curthread->td_dupfd to contain the value of the 5004 * the file descriptor being sought for duplication. The error 5005 * return ensures that the vnode for this device will be released 5006 * by vn_open. Open will detect this special error and take the 5007 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 5008 * will simply report the error. 5009 */ 5010 td->td_dupfd = dev2unit(dev); 5011 return (ENODEV); 5012 } 5013 5014 static struct cdevsw fildesc_cdevsw = { 5015 .d_version = D_VERSION, 5016 .d_open = fdopen, 5017 .d_name = "FD", 5018 }; 5019 5020 static void 5021 fildesc_drvinit(void *unused) 5022 { 5023 struct cdev *dev; 5024 5025 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 5026 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 5027 make_dev_alias(dev, "stdin"); 5028 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 5029 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 5030 make_dev_alias(dev, "stdout"); 5031 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 5032 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 5033 make_dev_alias(dev, "stderr"); 5034 } 5035 5036 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 5037