kern_descrip.c revision 280258
1298823Sbapt/*- 2298823Sbapt * Copyright (c) 1982, 1986, 1989, 1991, 1993 3298823Sbapt * The Regents of the University of California. All rights reserved. 4298823Sbapt * (c) UNIX System Laboratories, Inc. 5298823Sbapt * All or some portions of this file are derived from material licensed 6298823Sbapt * to the University of California by American Telephone and Telegraph 7298823Sbapt * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8298823Sbapt * the permission of UNIX System Laboratories, Inc. 9298823Sbapt * 10298823Sbapt * Redistribution and use in source and binary forms, with or without 11298823Sbapt * modification, are permitted provided that the following conditions 12298823Sbapt * are met: 13298823Sbapt * 1. Redistributions of source code must retain the above copyright 14298823Sbapt * notice, this list of conditions and the following disclaimer. 15298823Sbapt * 2. Redistributions in binary form must reproduce the above copyright 16298823Sbapt * notice, this list of conditions and the following disclaimer in the 17298823Sbapt * documentation and/or other materials provided with the distribution. 18298823Sbapt * 4. Neither the name of the University nor the names of its contributors 19298823Sbapt * may be used to endorse or promote products derived from this software 20298823Sbapt * without specific prior written permission. 21298823Sbapt * 22298823Sbapt * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23298823Sbapt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24298823Sbapt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25298823Sbapt * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26298823Sbapt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27298823Sbapt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28298823Sbapt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29298823Sbapt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30298823Sbapt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31298823Sbapt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32298823Sbapt * SUCH DAMAGE. 33298823Sbapt * 34298823Sbapt * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 35298823Sbapt */ 36298823Sbapt 37298823Sbapt#include <sys/cdefs.h> 38298823Sbapt__FBSDID("$FreeBSD: stable/10/sys/kern/kern_descrip.c 280258 2015-03-19 13:37:36Z rwatson $"); 39298823Sbapt 40298823Sbapt#include "opt_capsicum.h" 41298823Sbapt#include "opt_compat.h" 42298823Sbapt#include "opt_ddb.h" 43298823Sbapt#include "opt_ktrace.h" 44298823Sbapt#include "opt_procdesc.h" 45298823Sbapt 46298823Sbapt#include <sys/param.h> 47298823Sbapt#include <sys/systm.h> 48298823Sbapt 49298823Sbapt#include <sys/capsicum.h> 50298823Sbapt#include <sys/conf.h> 51298823Sbapt#include <sys/domain.h> 52298823Sbapt#include <sys/fcntl.h> 53298823Sbapt#include <sys/file.h> 54298823Sbapt#include <sys/filedesc.h> 55298823Sbapt#include <sys/filio.h> 56298823Sbapt#include <sys/jail.h> 57298823Sbapt#include <sys/kernel.h> 58298823Sbapt#include <sys/ksem.h> 59298823Sbapt#include <sys/limits.h> 60298823Sbapt#include <sys/lock.h> 61298823Sbapt#include <sys/malloc.h> 62298823Sbapt#include <sys/mman.h> 63298823Sbapt#include <sys/mount.h> 64298823Sbapt#include <sys/mqueue.h> 65298823Sbapt#include <sys/mutex.h> 66298823Sbapt#include <sys/namei.h> 67298823Sbapt#include <sys/selinfo.h> 68298823Sbapt#include <sys/pipe.h> 69298823Sbapt#include <sys/priv.h> 70298823Sbapt#include <sys/proc.h> 71298823Sbapt#include <sys/procdesc.h> 72298823Sbapt#include <sys/protosw.h> 73298823Sbapt#include <sys/racct.h> 74298823Sbapt#include <sys/resourcevar.h> 75298823Sbapt#include <sys/sbuf.h> 76298823Sbapt#include <sys/signalvar.h> 77298823Sbapt#include <sys/socketvar.h> 78298823Sbapt#include <sys/stat.h> 79298823Sbapt#include <sys/sx.h> 80298823Sbapt#include <sys/syscallsubr.h> 81298823Sbapt#include <sys/sysctl.h> 82298823Sbapt#include <sys/sysproto.h> 83298823Sbapt#include <sys/tty.h> 84298823Sbapt#include <sys/unistd.h> 85298823Sbapt#include <sys/un.h> 86298823Sbapt#include <sys/unpcb.h> 87298823Sbapt#include <sys/user.h> 88298823Sbapt#include <sys/vnode.h> 89298823Sbapt#ifdef KTRACE 90298823Sbapt#include <sys/ktrace.h> 91298823Sbapt#endif 92298823Sbapt 93298823Sbapt#include <net/vnet.h> 94298823Sbapt 95298823Sbapt#include <netinet/in.h> 96298823Sbapt#include <netinet/in_pcb.h> 97298823Sbapt 98298823Sbapt#include <security/audit/audit.h> 99298823Sbapt 100298823Sbapt#include <vm/uma.h> 101298823Sbapt#include <vm/vm.h> 102298823Sbapt 103298823Sbapt#include <ddb/ddb.h> 104298823Sbapt 105298823Sbaptstatic MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 106298823Sbaptstatic MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 107298823Sbapt "file desc to leader structures"); 108298823Sbaptstatic MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 109298823SbaptMALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 110298823Sbapt 111298823SbaptMALLOC_DECLARE(M_FADVISE); 112298823Sbapt 113298823Sbaptstatic uma_zone_t file_zone; 114298823Sbapt 115298823Sbaptvoid (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value); 116298823Sbapt 117298823Sbaptstatic int closefp(struct filedesc *fdp, int fd, struct file *fp, 118298823Sbapt struct thread *td, int holdleaders); 119298823Sbaptstatic int fd_first_free(struct filedesc *fdp, int low, int size); 120298823Sbaptstatic int fd_last_used(struct filedesc *fdp, int size); 121298823Sbaptstatic void fdgrowtable(struct filedesc *fdp, int nfd); 122298823Sbaptstatic void fdgrowtable_exp(struct filedesc *fdp, int nfd); 123298823Sbaptstatic void fdunused(struct filedesc *fdp, int fd); 124298823Sbaptstatic void fdused(struct filedesc *fdp, int fd); 125298823Sbaptstatic int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); 126298823Sbaptstatic int fill_procdesc_info(struct procdesc *pdp, 127298823Sbapt struct kinfo_file *kif); 128298823Sbaptstatic int fill_pts_info(struct tty *tp, struct kinfo_file *kif); 129298823Sbaptstatic int fill_sem_info(struct file *fp, struct kinfo_file *kif); 130298823Sbaptstatic int fill_shm_info(struct file *fp, struct kinfo_file *kif); 131298823Sbaptstatic int fill_socket_info(struct socket *so, struct kinfo_file *kif); 132298823Sbaptstatic int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); 133298823Sbaptstatic int getmaxfd(struct proc *p); 134298823Sbapt 135298823Sbapt/* 136298823Sbapt * Each process has: 137298823Sbapt * 138298823Sbapt * - An array of open file descriptors (fd_ofiles) 139298823Sbapt * - An array of file flags (fd_ofileflags) 140298823Sbapt * - A bitmap recording which descriptors are in use (fd_map) 141298823Sbapt * 142298823Sbapt * A process starts out with NDFILE descriptors. The value of NDFILE has 143298823Sbapt * been selected based the historical limit of 20 open files, and an 144298823Sbapt * assumption that the majority of processes, especially short-lived 145298823Sbapt * processes like shells, will never need more. 146298823Sbapt * 147298823Sbapt * If this initial allocation is exhausted, a larger descriptor table and 148298823Sbapt * map are allocated dynamically, and the pointers in the process's struct 149298823Sbapt * filedesc are updated to point to those. This is repeated every time 150298823Sbapt * the process runs out of file descriptors (provided it hasn't hit its 151298823Sbapt * resource limit). 152298823Sbapt * 153298823Sbapt * Since threads may hold references to individual descriptor table 154298823Sbapt * entries, the tables are never freed. Instead, they are placed on a 155298823Sbapt * linked list and freed only when the struct filedesc is released. 156298823Sbapt */ 157298823Sbapt#define NDFILE 20 158298823Sbapt#define NDSLOTSIZE sizeof(NDSLOTTYPE) 159298823Sbapt#define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 160298823Sbapt#define NDSLOT(x) ((x) / NDENTRIES) 161298823Sbapt#define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 162298823Sbapt#define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 163298823Sbapt 164298823Sbapt/* 165298823Sbapt * SLIST entry used to keep track of ofiles which must be reclaimed when 166298823Sbapt * the process exits. 167298823Sbapt */ 168298823Sbaptstruct freetable { 169298823Sbapt struct filedescent *ft_table; 170298823Sbapt SLIST_ENTRY(freetable) ft_next; 171298823Sbapt}; 172298823Sbapt 173298823Sbapt/* 174298823Sbapt * Initial allocation: a filedesc structure + the head of SLIST used to 175298823Sbapt * keep track of old ofiles + enough space for NDFILE descriptors. 176298823Sbapt */ 177298823Sbaptstruct filedesc0 { 178298823Sbapt struct filedesc fd_fd; 179298823Sbapt SLIST_HEAD(, freetable) fd_free; 180298823Sbapt struct filedescent fd_dfiles[NDFILE]; 181298823Sbapt NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 182298823Sbapt}; 183298823Sbapt 184298823Sbapt/* 185298823Sbapt * Descriptor management. 186298823Sbapt */ 187298823Sbaptvolatile int openfiles; /* actual number of open files */ 188298823Sbaptstruct mtx sigio_lock; /* mtx to protect pointers to sigio */ 189298823Sbaptvoid (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 190298823Sbapt 191298823Sbapt/* A mutex to protect the association between a proc and filedesc. */ 192298823Sbaptstatic struct mtx fdesc_mtx; 193298823Sbapt 194298823Sbapt/* 195298823Sbapt * If low >= size, just return low. Otherwise find the first zero bit in the 196298823Sbapt * given bitmap, starting at low and not exceeding size - 1. Return size if 197298823Sbapt * not found. 198298823Sbapt */ 199298823Sbaptstatic int 200298823Sbaptfd_first_free(struct filedesc *fdp, int low, int size) 201298823Sbapt{ 202298823Sbapt NDSLOTTYPE *map = fdp->fd_map; 203298823Sbapt NDSLOTTYPE mask; 204298823Sbapt int off, maxoff; 205298823Sbapt 206298823Sbapt if (low >= size) 207298823Sbapt return (low); 208 209 off = NDSLOT(low); 210 if (low % NDENTRIES) { 211 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); 212 if ((mask &= ~map[off]) != 0UL) 213 return (off * NDENTRIES + ffsl(mask) - 1); 214 ++off; 215 } 216 for (maxoff = NDSLOTS(size); off < maxoff; ++off) 217 if (map[off] != ~0UL) 218 return (off * NDENTRIES + ffsl(~map[off]) - 1); 219 return (size); 220} 221 222/* 223 * Find the highest non-zero bit in the given bitmap, starting at 0 and 224 * not exceeding size - 1. Return -1 if not found. 225 */ 226static int 227fd_last_used(struct filedesc *fdp, int size) 228{ 229 NDSLOTTYPE *map = fdp->fd_map; 230 NDSLOTTYPE mask; 231 int off, minoff; 232 233 off = NDSLOT(size); 234 if (size % NDENTRIES) { 235 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); 236 if ((mask &= map[off]) != 0) 237 return (off * NDENTRIES + flsl(mask) - 1); 238 --off; 239 } 240 for (minoff = NDSLOT(0); off >= minoff; --off) 241 if (map[off] != 0) 242 return (off * NDENTRIES + flsl(map[off]) - 1); 243 return (-1); 244} 245 246static int 247fdisused(struct filedesc *fdp, int fd) 248{ 249 250 FILEDESC_LOCK_ASSERT(fdp); 251 252 KASSERT(fd >= 0 && fd < fdp->fd_nfiles, 253 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); 254 255 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); 256} 257 258/* 259 * Mark a file descriptor as used. 260 */ 261static void 262fdused(struct filedesc *fdp, int fd) 263{ 264 265 FILEDESC_XLOCK_ASSERT(fdp); 266 267 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); 268 269 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); 270 if (fd > fdp->fd_lastfile) 271 fdp->fd_lastfile = fd; 272 if (fd == fdp->fd_freefile) 273 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); 274} 275 276/* 277 * Mark a file descriptor as unused. 278 */ 279static void 280fdunused(struct filedesc *fdp, int fd) 281{ 282 283 FILEDESC_XLOCK_ASSERT(fdp); 284 285 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); 286 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 287 ("fd=%d is still in use", fd)); 288 289 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); 290 if (fd < fdp->fd_freefile) 291 fdp->fd_freefile = fd; 292 if (fd == fdp->fd_lastfile) 293 fdp->fd_lastfile = fd_last_used(fdp, fd); 294} 295 296/* 297 * Free a file descriptor. 298 * 299 * Avoid some work if fdp is about to be destroyed. 300 */ 301static inline void 302_fdfree(struct filedesc *fdp, int fd, int last) 303{ 304 struct filedescent *fde; 305 306 fde = &fdp->fd_ofiles[fd]; 307#ifdef CAPABILITIES 308 if (!last) 309 seq_write_begin(&fde->fde_seq); 310#endif 311 filecaps_free(&fde->fde_caps); 312 if (last) 313 return; 314 bzero(fde, fde_change_size); 315 fdunused(fdp, fd); 316#ifdef CAPABILITIES 317 seq_write_end(&fde->fde_seq); 318#endif 319} 320 321static inline void 322fdfree(struct filedesc *fdp, int fd) 323{ 324 325 _fdfree(fdp, fd, 0); 326} 327 328static inline void 329fdfree_last(struct filedesc *fdp, int fd) 330{ 331 332 _fdfree(fdp, fd, 1); 333} 334 335/* 336 * System calls on descriptors. 337 */ 338#ifndef _SYS_SYSPROTO_H_ 339struct getdtablesize_args { 340 int dummy; 341}; 342#endif 343/* ARGSUSED */ 344int 345sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 346{ 347 struct proc *p = td->td_proc; 348 uint64_t lim; 349 350 PROC_LOCK(p); 351 td->td_retval[0] = 352 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 353 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 354 PROC_UNLOCK(p); 355 if (lim < td->td_retval[0]) 356 td->td_retval[0] = lim; 357 return (0); 358} 359 360/* 361 * Duplicate a file descriptor to a particular value. 362 * 363 * Note: keep in mind that a potential race condition exists when closing 364 * descriptors from a shared descriptor table (via rfork). 365 */ 366#ifndef _SYS_SYSPROTO_H_ 367struct dup2_args { 368 u_int from; 369 u_int to; 370}; 371#endif 372/* ARGSUSED */ 373int 374sys_dup2(struct thread *td, struct dup2_args *uap) 375{ 376 377 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 378 td->td_retval)); 379} 380 381/* 382 * Duplicate a file descriptor. 383 */ 384#ifndef _SYS_SYSPROTO_H_ 385struct dup_args { 386 u_int fd; 387}; 388#endif 389/* ARGSUSED */ 390int 391sys_dup(struct thread *td, struct dup_args *uap) 392{ 393 394 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 395} 396 397/* 398 * The file control system call. 399 */ 400#ifndef _SYS_SYSPROTO_H_ 401struct fcntl_args { 402 int fd; 403 int cmd; 404 long arg; 405}; 406#endif 407/* ARGSUSED */ 408int 409sys_fcntl(struct thread *td, struct fcntl_args *uap) 410{ 411 412 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg)); 413} 414 415int 416kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg) 417{ 418 struct flock fl; 419 struct __oflock ofl; 420 intptr_t arg1; 421 int error; 422 423 error = 0; 424 switch (cmd) { 425 case F_OGETLK: 426 case F_OSETLK: 427 case F_OSETLKW: 428 /* 429 * Convert old flock structure to new. 430 */ 431 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl)); 432 fl.l_start = ofl.l_start; 433 fl.l_len = ofl.l_len; 434 fl.l_pid = ofl.l_pid; 435 fl.l_type = ofl.l_type; 436 fl.l_whence = ofl.l_whence; 437 fl.l_sysid = 0; 438 439 switch (cmd) { 440 case F_OGETLK: 441 cmd = F_GETLK; 442 break; 443 case F_OSETLK: 444 cmd = F_SETLK; 445 break; 446 case F_OSETLKW: 447 cmd = F_SETLKW; 448 break; 449 } 450 arg1 = (intptr_t)&fl; 451 break; 452 case F_GETLK: 453 case F_SETLK: 454 case F_SETLKW: 455 case F_SETLK_REMOTE: 456 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl)); 457 arg1 = (intptr_t)&fl; 458 break; 459 default: 460 arg1 = arg; 461 break; 462 } 463 if (error) 464 return (error); 465 error = kern_fcntl(td, fd, cmd, arg1); 466 if (error) 467 return (error); 468 if (cmd == F_OGETLK) { 469 ofl.l_start = fl.l_start; 470 ofl.l_len = fl.l_len; 471 ofl.l_pid = fl.l_pid; 472 ofl.l_type = fl.l_type; 473 ofl.l_whence = fl.l_whence; 474 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl)); 475 } else if (cmd == F_GETLK) { 476 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl)); 477 } 478 return (error); 479} 480 481int 482kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 483{ 484 struct filedesc *fdp; 485 struct flock *flp; 486 struct file *fp, *fp2; 487 struct filedescent *fde; 488 struct proc *p; 489 struct vnode *vp; 490 cap_rights_t rights; 491 int error, flg, tmp; 492 uint64_t bsize; 493 off_t foffset; 494 495 error = 0; 496 flg = F_POSIX; 497 p = td->td_proc; 498 fdp = p->p_fd; 499 500 switch (cmd) { 501 case F_DUPFD: 502 tmp = arg; 503 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 504 break; 505 506 case F_DUPFD_CLOEXEC: 507 tmp = arg; 508 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 509 td->td_retval); 510 break; 511 512 case F_DUP2FD: 513 tmp = arg; 514 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 515 break; 516 517 case F_DUP2FD_CLOEXEC: 518 tmp = arg; 519 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 520 td->td_retval); 521 break; 522 523 case F_GETFD: 524 FILEDESC_SLOCK(fdp); 525 if ((fp = fget_locked(fdp, fd)) == NULL) { 526 FILEDESC_SUNLOCK(fdp); 527 error = EBADF; 528 break; 529 } 530 fde = &fdp->fd_ofiles[fd]; 531 td->td_retval[0] = 532 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 533 FILEDESC_SUNLOCK(fdp); 534 break; 535 536 case F_SETFD: 537 FILEDESC_XLOCK(fdp); 538 if ((fp = fget_locked(fdp, fd)) == NULL) { 539 FILEDESC_XUNLOCK(fdp); 540 error = EBADF; 541 break; 542 } 543 fde = &fdp->fd_ofiles[fd]; 544 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 545 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 546 FILEDESC_XUNLOCK(fdp); 547 break; 548 549 case F_GETFL: 550 error = fget_unlocked(fdp, fd, 551 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp, NULL); 552 if (error != 0) 553 break; 554 td->td_retval[0] = OFLAGS(fp->f_flag); 555 fdrop(fp, td); 556 break; 557 558 case F_SETFL: 559 error = fget_unlocked(fdp, fd, 560 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp, NULL); 561 if (error != 0) 562 break; 563 do { 564 tmp = flg = fp->f_flag; 565 tmp &= ~FCNTLFLAGS; 566 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 567 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 568 tmp = fp->f_flag & FNONBLOCK; 569 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 570 if (error != 0) { 571 fdrop(fp, td); 572 break; 573 } 574 tmp = fp->f_flag & FASYNC; 575 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 576 if (error == 0) { 577 fdrop(fp, td); 578 break; 579 } 580 atomic_clear_int(&fp->f_flag, FNONBLOCK); 581 tmp = 0; 582 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 583 fdrop(fp, td); 584 break; 585 586 case F_GETOWN: 587 error = fget_unlocked(fdp, fd, 588 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp, NULL); 589 if (error != 0) 590 break; 591 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 592 if (error == 0) 593 td->td_retval[0] = tmp; 594 fdrop(fp, td); 595 break; 596 597 case F_SETOWN: 598 error = fget_unlocked(fdp, fd, 599 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp, NULL); 600 if (error != 0) 601 break; 602 tmp = arg; 603 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 604 fdrop(fp, td); 605 break; 606 607 case F_SETLK_REMOTE: 608 error = priv_check(td, PRIV_NFS_LOCKD); 609 if (error) 610 return (error); 611 flg = F_REMOTE; 612 goto do_setlk; 613 614 case F_SETLKW: 615 flg |= F_WAIT; 616 /* FALLTHROUGH F_SETLK */ 617 618 case F_SETLK: 619 do_setlk: 620 cap_rights_init(&rights, CAP_FLOCK); 621 error = fget_unlocked(fdp, fd, &rights, 0, &fp, NULL); 622 if (error != 0) 623 break; 624 if (fp->f_type != DTYPE_VNODE) { 625 error = EBADF; 626 fdrop(fp, td); 627 break; 628 } 629 630 flp = (struct flock *)arg; 631 if (flp->l_whence == SEEK_CUR) { 632 foffset = foffset_get(fp); 633 if (foffset < 0 || 634 (flp->l_start > 0 && 635 foffset > OFF_MAX - flp->l_start)) { 636 FILEDESC_SUNLOCK(fdp); 637 error = EOVERFLOW; 638 fdrop(fp, td); 639 break; 640 } 641 flp->l_start += foffset; 642 } 643 644 vp = fp->f_vnode; 645 switch (flp->l_type) { 646 case F_RDLCK: 647 if ((fp->f_flag & FREAD) == 0) { 648 error = EBADF; 649 break; 650 } 651 PROC_LOCK(p->p_leader); 652 p->p_leader->p_flag |= P_ADVLOCK; 653 PROC_UNLOCK(p->p_leader); 654 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 655 flp, flg); 656 break; 657 case F_WRLCK: 658 if ((fp->f_flag & FWRITE) == 0) { 659 error = EBADF; 660 break; 661 } 662 PROC_LOCK(p->p_leader); 663 p->p_leader->p_flag |= P_ADVLOCK; 664 PROC_UNLOCK(p->p_leader); 665 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 666 flp, flg); 667 break; 668 case F_UNLCK: 669 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 670 flp, flg); 671 break; 672 case F_UNLCKSYS: 673 /* 674 * Temporary api for testing remote lock 675 * infrastructure. 676 */ 677 if (flg != F_REMOTE) { 678 error = EINVAL; 679 break; 680 } 681 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 682 F_UNLCKSYS, flp, flg); 683 break; 684 default: 685 error = EINVAL; 686 break; 687 } 688 if (error != 0 || flp->l_type == F_UNLCK || 689 flp->l_type == F_UNLCKSYS) { 690 fdrop(fp, td); 691 break; 692 } 693 694 /* 695 * Check for a race with close. 696 * 697 * The vnode is now advisory locked (or unlocked, but this case 698 * is not really important) as the caller requested. 699 * We had to drop the filedesc lock, so we need to recheck if 700 * the descriptor is still valid, because if it was closed 701 * in the meantime we need to remove advisory lock from the 702 * vnode - close on any descriptor leading to an advisory 703 * locked vnode, removes that lock. 704 * We will return 0 on purpose in that case, as the result of 705 * successful advisory lock might have been externally visible 706 * already. This is fine - effectively we pretend to the caller 707 * that the closing thread was a bit slower and that the 708 * advisory lock succeeded before the close. 709 */ 710 error = fget_unlocked(fdp, fd, &rights, 0, &fp2, NULL); 711 if (error != 0) { 712 fdrop(fp, td); 713 break; 714 } 715 if (fp != fp2) { 716 flp->l_whence = SEEK_SET; 717 flp->l_start = 0; 718 flp->l_len = 0; 719 flp->l_type = F_UNLCK; 720 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 721 F_UNLCK, flp, F_POSIX); 722 } 723 fdrop(fp, td); 724 fdrop(fp2, td); 725 break; 726 727 case F_GETLK: 728 error = fget_unlocked(fdp, fd, 729 cap_rights_init(&rights, CAP_FLOCK), 0, &fp, NULL); 730 if (error != 0) 731 break; 732 if (fp->f_type != DTYPE_VNODE) { 733 error = EBADF; 734 fdrop(fp, td); 735 break; 736 } 737 flp = (struct flock *)arg; 738 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 739 flp->l_type != F_UNLCK) { 740 error = EINVAL; 741 fdrop(fp, td); 742 break; 743 } 744 if (flp->l_whence == SEEK_CUR) { 745 foffset = foffset_get(fp); 746 if ((flp->l_start > 0 && 747 foffset > OFF_MAX - flp->l_start) || 748 (flp->l_start < 0 && 749 foffset < OFF_MIN - flp->l_start)) { 750 FILEDESC_SUNLOCK(fdp); 751 error = EOVERFLOW; 752 fdrop(fp, td); 753 break; 754 } 755 flp->l_start += foffset; 756 } 757 vp = fp->f_vnode; 758 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 759 F_POSIX); 760 fdrop(fp, td); 761 break; 762 763 case F_RDAHEAD: 764 arg = arg ? 128 * 1024: 0; 765 /* FALLTHROUGH */ 766 case F_READAHEAD: 767 error = fget_unlocked(fdp, fd, NULL, 0, &fp, NULL); 768 if (error != 0) 769 break; 770 if (fp->f_type != DTYPE_VNODE) { 771 fdrop(fp, td); 772 error = EBADF; 773 break; 774 } 775 vp = fp->f_vnode; 776 /* 777 * Exclusive lock synchronizes against f_seqcount reads and 778 * writes in sequential_heuristic(). 779 */ 780 error = vn_lock(vp, LK_EXCLUSIVE); 781 if (error != 0) { 782 fdrop(fp, td); 783 break; 784 } 785 if (arg >= 0) { 786 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 787 fp->f_seqcount = (arg + bsize - 1) / bsize; 788 atomic_set_int(&fp->f_flag, FRDAHEAD); 789 } else { 790 atomic_clear_int(&fp->f_flag, FRDAHEAD); 791 } 792 VOP_UNLOCK(vp, 0); 793 fdrop(fp, td); 794 break; 795 796 default: 797 error = EINVAL; 798 break; 799 } 800 return (error); 801} 802 803static int 804getmaxfd(struct proc *p) 805{ 806 int maxfd; 807 808 PROC_LOCK(p); 809 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 810 PROC_UNLOCK(p); 811 812 return (maxfd); 813} 814 815/* 816 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 817 */ 818int 819do_dup(struct thread *td, int flags, int old, int new, 820 register_t *retval) 821{ 822 struct filedesc *fdp; 823 struct filedescent *oldfde, *newfde; 824 struct proc *p; 825 struct file *fp; 826 struct file *delfp; 827 int error, maxfd; 828 829 p = td->td_proc; 830 fdp = p->p_fd; 831 832 /* 833 * Verify we have a valid descriptor to dup from and possibly to 834 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 835 * return EINVAL when the new descriptor is out of bounds. 836 */ 837 if (old < 0) 838 return (EBADF); 839 if (new < 0) 840 return (flags & DUP_FCNTL ? EINVAL : EBADF); 841 maxfd = getmaxfd(p); 842 if (new >= maxfd) 843 return (flags & DUP_FCNTL ? EINVAL : EBADF); 844 845 FILEDESC_XLOCK(fdp); 846 if (fget_locked(fdp, old) == NULL) { 847 FILEDESC_XUNLOCK(fdp); 848 return (EBADF); 849 } 850 oldfde = &fdp->fd_ofiles[old]; 851 if (flags & DUP_FIXED && old == new) { 852 *retval = new; 853 if (flags & DUP_CLOEXEC) 854 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 855 FILEDESC_XUNLOCK(fdp); 856 return (0); 857 } 858 fp = oldfde->fde_file; 859 fhold(fp); 860 861 /* 862 * If the caller specified a file descriptor, make sure the file 863 * table is large enough to hold it, and grab it. Otherwise, just 864 * allocate a new descriptor the usual way. 865 */ 866 if (flags & DUP_FIXED) { 867 if (new >= fdp->fd_nfiles) { 868 /* 869 * The resource limits are here instead of e.g. 870 * fdalloc(), because the file descriptor table may be 871 * shared between processes, so we can't really use 872 * racct_add()/racct_sub(). Instead of counting the 873 * number of actually allocated descriptors, just put 874 * the limit on the size of the file descriptor table. 875 */ 876#ifdef RACCT 877 PROC_LOCK(p); 878 error = racct_set(p, RACCT_NOFILE, new + 1); 879 PROC_UNLOCK(p); 880 if (error != 0) { 881 FILEDESC_XUNLOCK(fdp); 882 fdrop(fp, td); 883 return (EMFILE); 884 } 885#endif 886 fdgrowtable_exp(fdp, new + 1); 887 oldfde = &fdp->fd_ofiles[old]; 888 } 889 newfde = &fdp->fd_ofiles[new]; 890 if (newfde->fde_file == NULL) 891 fdused(fdp, new); 892 } else { 893 if ((error = fdalloc(td, new, &new)) != 0) { 894 FILEDESC_XUNLOCK(fdp); 895 fdrop(fp, td); 896 return (error); 897 } 898 newfde = &fdp->fd_ofiles[new]; 899 } 900 901 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 902 KASSERT(old != new, ("new fd is same as old")); 903 904 delfp = newfde->fde_file; 905 906 /* 907 * Duplicate the source descriptor. 908 */ 909#ifdef CAPABILITIES 910 seq_write_begin(&newfde->fde_seq); 911#endif 912 filecaps_free(&newfde->fde_caps); 913 memcpy(newfde, oldfde, fde_change_size); 914 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 915 if ((flags & DUP_CLOEXEC) != 0) 916 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 917 else 918 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 919#ifdef CAPABILITIES 920 seq_write_end(&newfde->fde_seq); 921#endif 922 *retval = new; 923 924 if (delfp != NULL) { 925 (void) closefp(fdp, new, delfp, td, 1); 926 /* closefp() drops the FILEDESC lock for us. */ 927 } else { 928 FILEDESC_XUNLOCK(fdp); 929 } 930 931 return (0); 932} 933 934/* 935 * If sigio is on the list associated with a process or process group, 936 * disable signalling from the device, remove sigio from the list and 937 * free sigio. 938 */ 939void 940funsetown(struct sigio **sigiop) 941{ 942 struct sigio *sigio; 943 944 SIGIO_LOCK(); 945 sigio = *sigiop; 946 if (sigio == NULL) { 947 SIGIO_UNLOCK(); 948 return; 949 } 950 *(sigio->sio_myref) = NULL; 951 if ((sigio)->sio_pgid < 0) { 952 struct pgrp *pg = (sigio)->sio_pgrp; 953 PGRP_LOCK(pg); 954 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 955 sigio, sio_pgsigio); 956 PGRP_UNLOCK(pg); 957 } else { 958 struct proc *p = (sigio)->sio_proc; 959 PROC_LOCK(p); 960 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 961 sigio, sio_pgsigio); 962 PROC_UNLOCK(p); 963 } 964 SIGIO_UNLOCK(); 965 crfree(sigio->sio_ucred); 966 free(sigio, M_SIGIO); 967} 968 969/* 970 * Free a list of sigio structures. 971 * We only need to lock the SIGIO_LOCK because we have made ourselves 972 * inaccessible to callers of fsetown and therefore do not need to lock 973 * the proc or pgrp struct for the list manipulation. 974 */ 975void 976funsetownlst(struct sigiolst *sigiolst) 977{ 978 struct proc *p; 979 struct pgrp *pg; 980 struct sigio *sigio; 981 982 sigio = SLIST_FIRST(sigiolst); 983 if (sigio == NULL) 984 return; 985 p = NULL; 986 pg = NULL; 987 988 /* 989 * Every entry of the list should belong 990 * to a single proc or pgrp. 991 */ 992 if (sigio->sio_pgid < 0) { 993 pg = sigio->sio_pgrp; 994 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 995 } else /* if (sigio->sio_pgid > 0) */ { 996 p = sigio->sio_proc; 997 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 998 } 999 1000 SIGIO_LOCK(); 1001 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 1002 *(sigio->sio_myref) = NULL; 1003 if (pg != NULL) { 1004 KASSERT(sigio->sio_pgid < 0, 1005 ("Proc sigio in pgrp sigio list")); 1006 KASSERT(sigio->sio_pgrp == pg, 1007 ("Bogus pgrp in sigio list")); 1008 PGRP_LOCK(pg); 1009 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 1010 sio_pgsigio); 1011 PGRP_UNLOCK(pg); 1012 } else /* if (p != NULL) */ { 1013 KASSERT(sigio->sio_pgid > 0, 1014 ("Pgrp sigio in proc sigio list")); 1015 KASSERT(sigio->sio_proc == p, 1016 ("Bogus proc in sigio list")); 1017 PROC_LOCK(p); 1018 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 1019 sio_pgsigio); 1020 PROC_UNLOCK(p); 1021 } 1022 SIGIO_UNLOCK(); 1023 crfree(sigio->sio_ucred); 1024 free(sigio, M_SIGIO); 1025 SIGIO_LOCK(); 1026 } 1027 SIGIO_UNLOCK(); 1028} 1029 1030/* 1031 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1032 * 1033 * After permission checking, add a sigio structure to the sigio list for 1034 * the process or process group. 1035 */ 1036int 1037fsetown(pid_t pgid, struct sigio **sigiop) 1038{ 1039 struct proc *proc; 1040 struct pgrp *pgrp; 1041 struct sigio *sigio; 1042 int ret; 1043 1044 if (pgid == 0) { 1045 funsetown(sigiop); 1046 return (0); 1047 } 1048 1049 ret = 0; 1050 1051 /* Allocate and fill in the new sigio out of locks. */ 1052 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1053 sigio->sio_pgid = pgid; 1054 sigio->sio_ucred = crhold(curthread->td_ucred); 1055 sigio->sio_myref = sigiop; 1056 1057 sx_slock(&proctree_lock); 1058 if (pgid > 0) { 1059 proc = pfind(pgid); 1060 if (proc == NULL) { 1061 ret = ESRCH; 1062 goto fail; 1063 } 1064 1065 /* 1066 * Policy - Don't allow a process to FSETOWN a process 1067 * in another session. 1068 * 1069 * Remove this test to allow maximum flexibility or 1070 * restrict FSETOWN to the current process or process 1071 * group for maximum safety. 1072 */ 1073 PROC_UNLOCK(proc); 1074 if (proc->p_session != curthread->td_proc->p_session) { 1075 ret = EPERM; 1076 goto fail; 1077 } 1078 1079 pgrp = NULL; 1080 } else /* if (pgid < 0) */ { 1081 pgrp = pgfind(-pgid); 1082 if (pgrp == NULL) { 1083 ret = ESRCH; 1084 goto fail; 1085 } 1086 PGRP_UNLOCK(pgrp); 1087 1088 /* 1089 * Policy - Don't allow a process to FSETOWN a process 1090 * in another session. 1091 * 1092 * Remove this test to allow maximum flexibility or 1093 * restrict FSETOWN to the current process or process 1094 * group for maximum safety. 1095 */ 1096 if (pgrp->pg_session != curthread->td_proc->p_session) { 1097 ret = EPERM; 1098 goto fail; 1099 } 1100 1101 proc = NULL; 1102 } 1103 funsetown(sigiop); 1104 if (pgid > 0) { 1105 PROC_LOCK(proc); 1106 /* 1107 * Since funsetownlst() is called without the proctree 1108 * locked, we need to check for P_WEXIT. 1109 * XXX: is ESRCH correct? 1110 */ 1111 if ((proc->p_flag & P_WEXIT) != 0) { 1112 PROC_UNLOCK(proc); 1113 ret = ESRCH; 1114 goto fail; 1115 } 1116 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1117 sigio->sio_proc = proc; 1118 PROC_UNLOCK(proc); 1119 } else { 1120 PGRP_LOCK(pgrp); 1121 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1122 sigio->sio_pgrp = pgrp; 1123 PGRP_UNLOCK(pgrp); 1124 } 1125 sx_sunlock(&proctree_lock); 1126 SIGIO_LOCK(); 1127 *sigiop = sigio; 1128 SIGIO_UNLOCK(); 1129 return (0); 1130 1131fail: 1132 sx_sunlock(&proctree_lock); 1133 crfree(sigio->sio_ucred); 1134 free(sigio, M_SIGIO); 1135 return (ret); 1136} 1137 1138/* 1139 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1140 */ 1141pid_t 1142fgetown(sigiop) 1143 struct sigio **sigiop; 1144{ 1145 pid_t pgid; 1146 1147 SIGIO_LOCK(); 1148 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1149 SIGIO_UNLOCK(); 1150 return (pgid); 1151} 1152 1153/* 1154 * Function drops the filedesc lock on return. 1155 */ 1156static int 1157closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1158 int holdleaders) 1159{ 1160 int error; 1161 1162 FILEDESC_XLOCK_ASSERT(fdp); 1163 1164 if (holdleaders) { 1165 if (td->td_proc->p_fdtol != NULL) { 1166 /* 1167 * Ask fdfree() to sleep to ensure that all relevant 1168 * process leaders can be traversed in closef(). 1169 */ 1170 fdp->fd_holdleaderscount++; 1171 } else { 1172 holdleaders = 0; 1173 } 1174 } 1175 1176 /* 1177 * We now hold the fp reference that used to be owned by the 1178 * descriptor array. We have to unlock the FILEDESC *AFTER* 1179 * knote_fdclose to prevent a race of the fd getting opened, a knote 1180 * added, and deleteing a knote for the new fd. 1181 */ 1182 knote_fdclose(td, fd); 1183 1184 /* 1185 * We need to notify mqueue if the object is of type mqueue. 1186 */ 1187 if (fp->f_type == DTYPE_MQUEUE) 1188 mq_fdclose(td, fd, fp); 1189 FILEDESC_XUNLOCK(fdp); 1190 1191 error = closef(fp, td); 1192 if (holdleaders) { 1193 FILEDESC_XLOCK(fdp); 1194 fdp->fd_holdleaderscount--; 1195 if (fdp->fd_holdleaderscount == 0 && 1196 fdp->fd_holdleaderswakeup != 0) { 1197 fdp->fd_holdleaderswakeup = 0; 1198 wakeup(&fdp->fd_holdleaderscount); 1199 } 1200 FILEDESC_XUNLOCK(fdp); 1201 } 1202 return (error); 1203} 1204 1205/* 1206 * Close a file descriptor. 1207 */ 1208#ifndef _SYS_SYSPROTO_H_ 1209struct close_args { 1210 int fd; 1211}; 1212#endif 1213/* ARGSUSED */ 1214int 1215sys_close(td, uap) 1216 struct thread *td; 1217 struct close_args *uap; 1218{ 1219 1220 return (kern_close(td, uap->fd)); 1221} 1222 1223int 1224kern_close(td, fd) 1225 struct thread *td; 1226 int fd; 1227{ 1228 struct filedesc *fdp; 1229 struct file *fp; 1230 1231 fdp = td->td_proc->p_fd; 1232 1233 AUDIT_SYSCLOSE(td, fd); 1234 1235 FILEDESC_XLOCK(fdp); 1236 if ((fp = fget_locked(fdp, fd)) == NULL) { 1237 FILEDESC_XUNLOCK(fdp); 1238 return (EBADF); 1239 } 1240 fdfree(fdp, fd); 1241 1242 /* closefp() drops the FILEDESC lock for us. */ 1243 return (closefp(fdp, fd, fp, td, 1)); 1244} 1245 1246/* 1247 * Close open file descriptors. 1248 */ 1249#ifndef _SYS_SYSPROTO_H_ 1250struct closefrom_args { 1251 int lowfd; 1252}; 1253#endif 1254/* ARGSUSED */ 1255int 1256sys_closefrom(struct thread *td, struct closefrom_args *uap) 1257{ 1258 struct filedesc *fdp; 1259 int fd; 1260 1261 fdp = td->td_proc->p_fd; 1262 AUDIT_ARG_FD(uap->lowfd); 1263 1264 /* 1265 * Treat negative starting file descriptor values identical to 1266 * closefrom(0) which closes all files. 1267 */ 1268 if (uap->lowfd < 0) 1269 uap->lowfd = 0; 1270 FILEDESC_SLOCK(fdp); 1271 for (fd = uap->lowfd; fd <= fdp->fd_lastfile; fd++) { 1272 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1273 FILEDESC_SUNLOCK(fdp); 1274 (void)kern_close(td, fd); 1275 FILEDESC_SLOCK(fdp); 1276 } 1277 } 1278 FILEDESC_SUNLOCK(fdp); 1279 return (0); 1280} 1281 1282#if defined(COMPAT_43) 1283/* 1284 * Return status information about a file descriptor. 1285 */ 1286#ifndef _SYS_SYSPROTO_H_ 1287struct ofstat_args { 1288 int fd; 1289 struct ostat *sb; 1290}; 1291#endif 1292/* ARGSUSED */ 1293int 1294ofstat(struct thread *td, struct ofstat_args *uap) 1295{ 1296 struct ostat oub; 1297 struct stat ub; 1298 int error; 1299 1300 error = kern_fstat(td, uap->fd, &ub); 1301 if (error == 0) { 1302 cvtstat(&ub, &oub); 1303 error = copyout(&oub, uap->sb, sizeof(oub)); 1304 } 1305 return (error); 1306} 1307#endif /* COMPAT_43 */ 1308 1309/* 1310 * Return status information about a file descriptor. 1311 */ 1312#ifndef _SYS_SYSPROTO_H_ 1313struct fstat_args { 1314 int fd; 1315 struct stat *sb; 1316}; 1317#endif 1318/* ARGSUSED */ 1319int 1320sys_fstat(struct thread *td, struct fstat_args *uap) 1321{ 1322 struct stat ub; 1323 int error; 1324 1325 error = kern_fstat(td, uap->fd, &ub); 1326 if (error == 0) 1327 error = copyout(&ub, uap->sb, sizeof(ub)); 1328 return (error); 1329} 1330 1331int 1332kern_fstat(struct thread *td, int fd, struct stat *sbp) 1333{ 1334 struct file *fp; 1335 cap_rights_t rights; 1336 int error; 1337 1338 AUDIT_ARG_FD(fd); 1339 1340 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1341 if (error != 0) 1342 return (error); 1343 1344 AUDIT_ARG_FILE(td->td_proc, fp); 1345 1346 error = fo_stat(fp, sbp, td->td_ucred, td); 1347 fdrop(fp, td); 1348#ifdef KTRACE 1349 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1350 ktrstat(sbp); 1351#endif 1352 return (error); 1353} 1354 1355/* 1356 * Return status information about a file descriptor. 1357 */ 1358#ifndef _SYS_SYSPROTO_H_ 1359struct nfstat_args { 1360 int fd; 1361 struct nstat *sb; 1362}; 1363#endif 1364/* ARGSUSED */ 1365int 1366sys_nfstat(struct thread *td, struct nfstat_args *uap) 1367{ 1368 struct nstat nub; 1369 struct stat ub; 1370 int error; 1371 1372 error = kern_fstat(td, uap->fd, &ub); 1373 if (error == 0) { 1374 cvtnstat(&ub, &nub); 1375 error = copyout(&nub, uap->sb, sizeof(nub)); 1376 } 1377 return (error); 1378} 1379 1380/* 1381 * Return pathconf information about a file descriptor. 1382 */ 1383#ifndef _SYS_SYSPROTO_H_ 1384struct fpathconf_args { 1385 int fd; 1386 int name; 1387}; 1388#endif 1389/* ARGSUSED */ 1390int 1391sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1392{ 1393 struct file *fp; 1394 struct vnode *vp; 1395 cap_rights_t rights; 1396 int error; 1397 1398 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1399 if (error != 0) 1400 return (error); 1401 1402 /* If asynchronous I/O is available, it works for all descriptors. */ 1403 if (uap->name == _PC_ASYNC_IO) { 1404 td->td_retval[0] = async_io_version; 1405 goto out; 1406 } 1407 vp = fp->f_vnode; 1408 if (vp != NULL) { 1409 vn_lock(vp, LK_SHARED | LK_RETRY); 1410 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1411 VOP_UNLOCK(vp, 0); 1412 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1413 if (uap->name != _PC_PIPE_BUF) { 1414 error = EINVAL; 1415 } else { 1416 td->td_retval[0] = PIPE_BUF; 1417 error = 0; 1418 } 1419 } else { 1420 error = EOPNOTSUPP; 1421 } 1422out: 1423 fdrop(fp, td); 1424 return (error); 1425} 1426 1427/* 1428 * Initialize filecaps structure. 1429 */ 1430void 1431filecaps_init(struct filecaps *fcaps) 1432{ 1433 1434 bzero(fcaps, sizeof(*fcaps)); 1435 fcaps->fc_nioctls = -1; 1436} 1437 1438/* 1439 * Copy filecaps structure allocating memory for ioctls array if needed. 1440 */ 1441void 1442filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1443{ 1444 size_t size; 1445 1446 *dst = *src; 1447 if (src->fc_ioctls != NULL) { 1448 KASSERT(src->fc_nioctls > 0, 1449 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1450 1451 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1452 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1453 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1454 } 1455} 1456 1457/* 1458 * Move filecaps structure to the new place and clear the old place. 1459 */ 1460void 1461filecaps_move(struct filecaps *src, struct filecaps *dst) 1462{ 1463 1464 *dst = *src; 1465 bzero(src, sizeof(*src)); 1466} 1467 1468/* 1469 * Fill the given filecaps structure with full rights. 1470 */ 1471static void 1472filecaps_fill(struct filecaps *fcaps) 1473{ 1474 1475 CAP_ALL(&fcaps->fc_rights); 1476 fcaps->fc_ioctls = NULL; 1477 fcaps->fc_nioctls = -1; 1478 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1479} 1480 1481/* 1482 * Free memory allocated within filecaps structure. 1483 */ 1484void 1485filecaps_free(struct filecaps *fcaps) 1486{ 1487 1488 free(fcaps->fc_ioctls, M_FILECAPS); 1489 bzero(fcaps, sizeof(*fcaps)); 1490} 1491 1492/* 1493 * Validate the given filecaps structure. 1494 */ 1495static void 1496filecaps_validate(const struct filecaps *fcaps, const char *func) 1497{ 1498 1499 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1500 ("%s: invalid rights", func)); 1501 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1502 ("%s: invalid fcntls", func)); 1503 KASSERT(fcaps->fc_fcntls == 0 || 1504 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1505 ("%s: fcntls without CAP_FCNTL", func)); 1506 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1507 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1508 ("%s: invalid ioctls", func)); 1509 KASSERT(fcaps->fc_nioctls == 0 || 1510 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1511 ("%s: ioctls without CAP_IOCTL", func)); 1512} 1513 1514static void 1515fdgrowtable_exp(struct filedesc *fdp, int nfd) 1516{ 1517 int nfd1; 1518 1519 FILEDESC_XLOCK_ASSERT(fdp); 1520 1521 nfd1 = fdp->fd_nfiles * 2; 1522 if (nfd1 < nfd) 1523 nfd1 = nfd; 1524 fdgrowtable(fdp, nfd1); 1525} 1526 1527/* 1528 * Grow the file table to accomodate (at least) nfd descriptors. 1529 */ 1530static void 1531fdgrowtable(struct filedesc *fdp, int nfd) 1532{ 1533 struct filedesc0 *fdp0; 1534 struct freetable *ft; 1535 struct filedescent *ntable; 1536 struct filedescent *otable; 1537 int nnfiles, onfiles; 1538 NDSLOTTYPE *nmap, *omap; 1539 1540 FILEDESC_XLOCK_ASSERT(fdp); 1541 1542 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1543 1544 /* save old values */ 1545 onfiles = fdp->fd_nfiles; 1546 otable = fdp->fd_ofiles; 1547 omap = fdp->fd_map; 1548 1549 /* compute the size of the new table */ 1550 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1551 if (nnfiles <= onfiles) 1552 /* the table is already large enough */ 1553 return; 1554 1555 /* 1556 * Allocate a new table. We need enough space for the 1557 * file entries themselves and the struct freetable we will use 1558 * when we decommission the table and place it on the freelist. 1559 * We place the struct freetable in the middle so we don't have 1560 * to worry about padding. 1561 */ 1562 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1563 M_FILEDESC, M_ZERO | M_WAITOK); 1564 /* copy the old data over and point at the new tables */ 1565 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1566 fdp->fd_ofiles = ntable; 1567 1568 /* 1569 * Allocate a new map only if the old is not large enough. It will 1570 * grow at a slower rate than the table as it can map more 1571 * entries than the table can hold. 1572 */ 1573 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { 1574 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1575 M_ZERO | M_WAITOK); 1576 /* copy over the old data and update the pointer */ 1577 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1578 fdp->fd_map = nmap; 1579 } 1580 1581 /* 1582 * In order to have a valid pattern for fget_unlocked() 1583 * fdp->fd_nfiles must be the last member to be updated, otherwise 1584 * fget_unlocked() consumers may reference a new, higher value for 1585 * fdp->fd_nfiles before to access the fdp->fd_ofiles array, 1586 * resulting in OOB accesses. 1587 */ 1588 atomic_store_rel_int(&fdp->fd_nfiles, nnfiles); 1589 1590 /* 1591 * Do not free the old file table, as some threads may still 1592 * reference entries within it. Instead, place it on a freelist 1593 * which will be processed when the struct filedesc is released. 1594 * 1595 * Note that if onfiles == NDFILE, we're dealing with the original 1596 * static allocation contained within (struct filedesc0 *)fdp, 1597 * which must not be freed. 1598 */ 1599 if (onfiles > NDFILE) { 1600 ft = (struct freetable *)&otable[onfiles]; 1601 fdp0 = (struct filedesc0 *)fdp; 1602 ft->ft_table = otable; 1603 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1604 } 1605 /* 1606 * The map does not have the same possibility of threads still 1607 * holding references to it. So always free it as long as it 1608 * does not reference the original static allocation. 1609 */ 1610 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) 1611 free(omap, M_FILEDESC); 1612} 1613 1614/* 1615 * Allocate a file descriptor for the process. 1616 */ 1617int 1618fdalloc(struct thread *td, int minfd, int *result) 1619{ 1620 struct proc *p = td->td_proc; 1621 struct filedesc *fdp = p->p_fd; 1622 int fd = -1, maxfd, allocfd; 1623#ifdef RACCT 1624 int error; 1625#endif 1626 1627 FILEDESC_XLOCK_ASSERT(fdp); 1628 1629 if (fdp->fd_freefile > minfd) 1630 minfd = fdp->fd_freefile; 1631 1632 maxfd = getmaxfd(p); 1633 1634 /* 1635 * Search the bitmap for a free descriptor starting at minfd. 1636 * If none is found, grow the file table. 1637 */ 1638 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1639 if (fd >= maxfd) 1640 return (EMFILE); 1641 if (fd >= fdp->fd_nfiles) { 1642 allocfd = min(fd * 2, maxfd); 1643#ifdef RACCT 1644 PROC_LOCK(p); 1645 error = racct_set(p, RACCT_NOFILE, allocfd); 1646 PROC_UNLOCK(p); 1647 if (error != 0) 1648 return (EMFILE); 1649#endif 1650 /* 1651 * fd is already equal to first free descriptor >= minfd, so 1652 * we only need to grow the table and we are done. 1653 */ 1654 fdgrowtable_exp(fdp, allocfd); 1655 } 1656 1657 /* 1658 * Perform some sanity checks, then mark the file descriptor as 1659 * used and return it to the caller. 1660 */ 1661 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1662 ("invalid descriptor %d", fd)); 1663 KASSERT(!fdisused(fdp, fd), 1664 ("fd_first_free() returned non-free descriptor")); 1665 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1666 ("file descriptor isn't free")); 1667 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1668 fdused(fdp, fd); 1669 *result = fd; 1670 return (0); 1671} 1672 1673/* 1674 * Allocate n file descriptors for the process. 1675 */ 1676int 1677fdallocn(struct thread *td, int minfd, int *fds, int n) 1678{ 1679 struct proc *p = td->td_proc; 1680 struct filedesc *fdp = p->p_fd; 1681 int i; 1682 1683 FILEDESC_XLOCK_ASSERT(fdp); 1684 1685 if (!fdavail(td, n)) 1686 return (EMFILE); 1687 1688 for (i = 0; i < n; i++) 1689 if (fdalloc(td, 0, &fds[i]) != 0) 1690 break; 1691 1692 if (i < n) { 1693 for (i--; i >= 0; i--) 1694 fdunused(fdp, fds[i]); 1695 return (EMFILE); 1696 } 1697 1698 return (0); 1699} 1700 1701/* 1702 * Check to see whether n user file descriptors are available to the process 1703 * p. 1704 */ 1705int 1706fdavail(struct thread *td, int n) 1707{ 1708 struct proc *p = td->td_proc; 1709 struct filedesc *fdp = td->td_proc->p_fd; 1710 int i, lim, last; 1711 1712 FILEDESC_LOCK_ASSERT(fdp); 1713 1714 /* 1715 * XXX: This is only called from uipc_usrreq.c:unp_externalize(); 1716 * call racct_add() from there instead of dealing with containers 1717 * here. 1718 */ 1719 lim = getmaxfd(p); 1720 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) 1721 return (1); 1722 last = min(fdp->fd_nfiles, lim); 1723 for (i = fdp->fd_freefile; i < last; i++) { 1724 if (fdp->fd_ofiles[i].fde_file == NULL && --n <= 0) 1725 return (1); 1726 } 1727 return (0); 1728} 1729 1730/* 1731 * Create a new open file structure and allocate a file decriptor for the 1732 * process that refers to it. We add one reference to the file for the 1733 * descriptor table and one reference for resultfp. This is to prevent us 1734 * being preempted and the entry in the descriptor table closed after we 1735 * release the FILEDESC lock. 1736 */ 1737int 1738falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1739{ 1740 struct file *fp; 1741 int error, fd; 1742 1743 error = falloc_noinstall(td, &fp); 1744 if (error) 1745 return (error); /* no reference held on error */ 1746 1747 error = finstall(td, fp, &fd, flags, NULL); 1748 if (error) { 1749 fdrop(fp, td); /* one reference (fp only) */ 1750 return (error); 1751 } 1752 1753 if (resultfp != NULL) 1754 *resultfp = fp; /* copy out result */ 1755 else 1756 fdrop(fp, td); /* release local reference */ 1757 1758 if (resultfd != NULL) 1759 *resultfd = fd; 1760 1761 return (0); 1762} 1763 1764/* 1765 * Create a new open file structure without allocating a file descriptor. 1766 */ 1767int 1768falloc_noinstall(struct thread *td, struct file **resultfp) 1769{ 1770 struct file *fp; 1771 int maxuserfiles = maxfiles - (maxfiles / 20); 1772 static struct timeval lastfail; 1773 static int curfail; 1774 1775 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1776 1777 if ((openfiles >= maxuserfiles && 1778 priv_check(td, PRIV_MAXFILES) != 0) || 1779 openfiles >= maxfiles) { 1780 if (ppsratecheck(&lastfail, &curfail, 1)) { 1781 printf("kern.maxfiles limit exceeded by uid %i, " 1782 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1783 } 1784 return (ENFILE); 1785 } 1786 atomic_add_int(&openfiles, 1); 1787 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1788 refcount_init(&fp->f_count, 1); 1789 fp->f_cred = crhold(td->td_ucred); 1790 fp->f_ops = &badfileops; 1791 fp->f_data = NULL; 1792 fp->f_vnode = NULL; 1793 *resultfp = fp; 1794 return (0); 1795} 1796 1797/* 1798 * Install a file in a file descriptor table. 1799 */ 1800int 1801finstall(struct thread *td, struct file *fp, int *fd, int flags, 1802 struct filecaps *fcaps) 1803{ 1804 struct filedesc *fdp = td->td_proc->p_fd; 1805 struct filedescent *fde; 1806 int error; 1807 1808 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1809 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1810 if (fcaps != NULL) 1811 filecaps_validate(fcaps, __func__); 1812 1813 FILEDESC_XLOCK(fdp); 1814 if ((error = fdalloc(td, 0, fd))) { 1815 FILEDESC_XUNLOCK(fdp); 1816 return (error); 1817 } 1818 fhold(fp); 1819 fde = &fdp->fd_ofiles[*fd]; 1820#ifdef CAPABILITIES 1821 seq_write_begin(&fde->fde_seq); 1822#endif 1823 fde->fde_file = fp; 1824 if ((flags & O_CLOEXEC) != 0) 1825 fde->fde_flags |= UF_EXCLOSE; 1826 if (fcaps != NULL) 1827 filecaps_move(fcaps, &fde->fde_caps); 1828 else 1829 filecaps_fill(&fde->fde_caps); 1830#ifdef CAPABILITIES 1831 seq_write_end(&fde->fde_seq); 1832#endif 1833 FILEDESC_XUNLOCK(fdp); 1834 return (0); 1835} 1836 1837/* 1838 * Build a new filedesc structure from another. 1839 * Copy the current, root, and jail root vnode references. 1840 */ 1841struct filedesc * 1842fdinit(struct filedesc *fdp) 1843{ 1844 struct filedesc0 *newfdp; 1845 1846 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1847 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1848 if (fdp != NULL) { 1849 FILEDESC_SLOCK(fdp); 1850 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1851 if (newfdp->fd_fd.fd_cdir) 1852 VREF(newfdp->fd_fd.fd_cdir); 1853 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1854 if (newfdp->fd_fd.fd_rdir) 1855 VREF(newfdp->fd_fd.fd_rdir); 1856 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1857 if (newfdp->fd_fd.fd_jdir) 1858 VREF(newfdp->fd_fd.fd_jdir); 1859 FILEDESC_SUNLOCK(fdp); 1860 } 1861 1862 /* Create the file descriptor table. */ 1863 newfdp->fd_fd.fd_refcnt = 1; 1864 newfdp->fd_fd.fd_holdcnt = 1; 1865 newfdp->fd_fd.fd_cmask = CMASK; 1866 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1867 newfdp->fd_fd.fd_nfiles = NDFILE; 1868 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1869 newfdp->fd_fd.fd_lastfile = -1; 1870 return (&newfdp->fd_fd); 1871} 1872 1873static struct filedesc * 1874fdhold(struct proc *p) 1875{ 1876 struct filedesc *fdp; 1877 1878 mtx_lock(&fdesc_mtx); 1879 fdp = p->p_fd; 1880 if (fdp != NULL) 1881 fdp->fd_holdcnt++; 1882 mtx_unlock(&fdesc_mtx); 1883 return (fdp); 1884} 1885 1886static void 1887fddrop(struct filedesc *fdp) 1888{ 1889 struct filedesc0 *fdp0; 1890 struct freetable *ft; 1891 int i; 1892 1893 mtx_lock(&fdesc_mtx); 1894 i = --fdp->fd_holdcnt; 1895 mtx_unlock(&fdesc_mtx); 1896 if (i > 0) 1897 return; 1898 1899 FILEDESC_LOCK_DESTROY(fdp); 1900 fdp0 = (struct filedesc0 *)fdp; 1901 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1902 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1903 free(ft->ft_table, M_FILEDESC); 1904 } 1905 free(fdp, M_FILEDESC); 1906} 1907 1908/* 1909 * Share a filedesc structure. 1910 */ 1911struct filedesc * 1912fdshare(struct filedesc *fdp) 1913{ 1914 1915 FILEDESC_XLOCK(fdp); 1916 fdp->fd_refcnt++; 1917 FILEDESC_XUNLOCK(fdp); 1918 return (fdp); 1919} 1920 1921/* 1922 * Unshare a filedesc structure, if necessary by making a copy 1923 */ 1924void 1925fdunshare(struct thread *td) 1926{ 1927 struct filedesc *tmp; 1928 struct proc *p = td->td_proc; 1929 1930 if (p->p_fd->fd_refcnt == 1) 1931 return; 1932 1933 tmp = fdcopy(p->p_fd); 1934 fdescfree(td); 1935 p->p_fd = tmp; 1936} 1937 1938/* 1939 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1940 * this is to ease callers, not catch errors. 1941 */ 1942struct filedesc * 1943fdcopy(struct filedesc *fdp) 1944{ 1945 struct filedesc *newfdp; 1946 struct filedescent *nfde, *ofde; 1947 int i; 1948 1949 /* Certain daemons might not have file descriptors. */ 1950 if (fdp == NULL) 1951 return (NULL); 1952 1953 newfdp = fdinit(fdp); 1954 FILEDESC_SLOCK(fdp); 1955 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1956 FILEDESC_SUNLOCK(fdp); 1957 FILEDESC_XLOCK(newfdp); 1958 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1959 FILEDESC_XUNLOCK(newfdp); 1960 FILEDESC_SLOCK(fdp); 1961 } 1962 /* copy all passable descriptors (i.e. not kqueue) */ 1963 newfdp->fd_freefile = -1; 1964 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1965 ofde = &fdp->fd_ofiles[i]; 1966 if (fdisused(fdp, i) && 1967 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1968 ofde->fde_file->f_ops != &badfileops) { 1969 nfde = &newfdp->fd_ofiles[i]; 1970 *nfde = *ofde; 1971 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1972 fhold(nfde->fde_file); 1973 newfdp->fd_lastfile = i; 1974 } else { 1975 if (newfdp->fd_freefile == -1) 1976 newfdp->fd_freefile = i; 1977 } 1978 } 1979 newfdp->fd_cmask = fdp->fd_cmask; 1980 FILEDESC_SUNLOCK(fdp); 1981 FILEDESC_XLOCK(newfdp); 1982 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1983 if (newfdp->fd_ofiles[i].fde_file != NULL) 1984 fdused(newfdp, i); 1985 } 1986 if (newfdp->fd_freefile == -1) 1987 newfdp->fd_freefile = i; 1988 FILEDESC_XUNLOCK(newfdp); 1989 return (newfdp); 1990} 1991 1992/* 1993 * Release a filedesc structure. 1994 */ 1995void 1996fdescfree(struct thread *td) 1997{ 1998 struct filedesc *fdp; 1999 int i; 2000 struct filedesc_to_leader *fdtol; 2001 struct file *fp; 2002 struct vnode *cdir, *jdir, *rdir, *vp; 2003 struct flock lf; 2004 2005 /* Certain daemons might not have file descriptors. */ 2006 fdp = td->td_proc->p_fd; 2007 if (fdp == NULL) 2008 return; 2009 2010#ifdef RACCT 2011 PROC_LOCK(td->td_proc); 2012 racct_set(td->td_proc, RACCT_NOFILE, 0); 2013 PROC_UNLOCK(td->td_proc); 2014#endif 2015 2016 /* Check for special need to clear POSIX style locks */ 2017 fdtol = td->td_proc->p_fdtol; 2018 if (fdtol != NULL) { 2019 FILEDESC_XLOCK(fdp); 2020 KASSERT(fdtol->fdl_refcount > 0, 2021 ("filedesc_to_refcount botch: fdl_refcount=%d", 2022 fdtol->fdl_refcount)); 2023 if (fdtol->fdl_refcount == 1 && 2024 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2025 for (i = 0; i <= fdp->fd_lastfile; i++) { 2026 fp = fdp->fd_ofiles[i].fde_file; 2027 if (fp == NULL || fp->f_type != DTYPE_VNODE) 2028 continue; 2029 fhold(fp); 2030 FILEDESC_XUNLOCK(fdp); 2031 lf.l_whence = SEEK_SET; 2032 lf.l_start = 0; 2033 lf.l_len = 0; 2034 lf.l_type = F_UNLCK; 2035 vp = fp->f_vnode; 2036 (void) VOP_ADVLOCK(vp, 2037 (caddr_t)td->td_proc->p_leader, F_UNLCK, 2038 &lf, F_POSIX); 2039 FILEDESC_XLOCK(fdp); 2040 fdrop(fp, td); 2041 } 2042 } 2043 retry: 2044 if (fdtol->fdl_refcount == 1) { 2045 if (fdp->fd_holdleaderscount > 0 && 2046 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2047 /* 2048 * close() or do_dup() has cleared a reference 2049 * in a shared file descriptor table. 2050 */ 2051 fdp->fd_holdleaderswakeup = 1; 2052 sx_sleep(&fdp->fd_holdleaderscount, 2053 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2054 goto retry; 2055 } 2056 if (fdtol->fdl_holdcount > 0) { 2057 /* 2058 * Ensure that fdtol->fdl_leader remains 2059 * valid in closef(). 2060 */ 2061 fdtol->fdl_wakeup = 1; 2062 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2063 "fdlhold", 0); 2064 goto retry; 2065 } 2066 } 2067 fdtol->fdl_refcount--; 2068 if (fdtol->fdl_refcount == 0 && 2069 fdtol->fdl_holdcount == 0) { 2070 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2071 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2072 } else 2073 fdtol = NULL; 2074 td->td_proc->p_fdtol = NULL; 2075 FILEDESC_XUNLOCK(fdp); 2076 if (fdtol != NULL) 2077 free(fdtol, M_FILEDESC_TO_LEADER); 2078 } 2079 2080 mtx_lock(&fdesc_mtx); 2081 td->td_proc->p_fd = NULL; 2082 mtx_unlock(&fdesc_mtx); 2083 2084 FILEDESC_XLOCK(fdp); 2085 i = --fdp->fd_refcnt; 2086 if (i > 0) { 2087 FILEDESC_XUNLOCK(fdp); 2088 return; 2089 } 2090 2091 cdir = fdp->fd_cdir; 2092 fdp->fd_cdir = NULL; 2093 rdir = fdp->fd_rdir; 2094 fdp->fd_rdir = NULL; 2095 jdir = fdp->fd_jdir; 2096 fdp->fd_jdir = NULL; 2097 FILEDESC_XUNLOCK(fdp); 2098 2099 for (i = 0; i <= fdp->fd_lastfile; i++) { 2100 fp = fdp->fd_ofiles[i].fde_file; 2101 if (fp != NULL) { 2102 fdfree_last(fdp, i); 2103 (void) closef(fp, td); 2104 } 2105 } 2106 2107 if (fdp->fd_nfiles > NDFILE) 2108 free(fdp->fd_ofiles, M_FILEDESC); 2109 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2110 free(fdp->fd_map, M_FILEDESC); 2111 2112 if (cdir != NULL) 2113 vrele(cdir); 2114 if (rdir != NULL) 2115 vrele(rdir); 2116 if (jdir != NULL) 2117 vrele(jdir); 2118 2119 fddrop(fdp); 2120} 2121 2122/* 2123 * For setugid programs, we don't want to people to use that setugidness 2124 * to generate error messages which write to a file which otherwise would 2125 * otherwise be off-limits to the process. We check for filesystems where 2126 * the vnode can change out from under us after execve (like [lin]procfs). 2127 * 2128 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2129 * sufficient. We also don't check for setugidness since we know we are. 2130 */ 2131static int 2132is_unsafe(struct file *fp) 2133{ 2134 if (fp->f_type == DTYPE_VNODE) { 2135 struct vnode *vp = fp->f_vnode; 2136 2137 if ((vp->v_vflag & VV_PROCDEP) != 0) 2138 return (1); 2139 } 2140 return (0); 2141} 2142 2143/* 2144 * Make this setguid thing safe, if at all possible. 2145 */ 2146void 2147setugidsafety(struct thread *td) 2148{ 2149 struct filedesc *fdp; 2150 struct file *fp; 2151 int i; 2152 2153 fdp = td->td_proc->p_fd; 2154 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2155 FILEDESC_XLOCK(fdp); 2156 for (i = 0; i <= fdp->fd_lastfile; i++) { 2157 if (i > 2) 2158 break; 2159 fp = fdp->fd_ofiles[i].fde_file; 2160 if (fp != NULL && is_unsafe(fp)) { 2161 knote_fdclose(td, i); 2162 /* 2163 * NULL-out descriptor prior to close to avoid 2164 * a race while close blocks. 2165 */ 2166 fdfree(fdp, i); 2167 FILEDESC_XUNLOCK(fdp); 2168 (void) closef(fp, td); 2169 FILEDESC_XLOCK(fdp); 2170 } 2171 } 2172 FILEDESC_XUNLOCK(fdp); 2173} 2174 2175/* 2176 * If a specific file object occupies a specific file descriptor, close the 2177 * file descriptor entry and drop a reference on the file object. This is a 2178 * convenience function to handle a subsequent error in a function that calls 2179 * falloc() that handles the race that another thread might have closed the 2180 * file descriptor out from under the thread creating the file object. 2181 */ 2182void 2183fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2184{ 2185 2186 FILEDESC_XLOCK(fdp); 2187 if (fdp->fd_ofiles[idx].fde_file == fp) { 2188 fdfree(fdp, idx); 2189 FILEDESC_XUNLOCK(fdp); 2190 fdrop(fp, td); 2191 } else 2192 FILEDESC_XUNLOCK(fdp); 2193} 2194 2195/* 2196 * Close any files on exec? 2197 */ 2198void 2199fdcloseexec(struct thread *td) 2200{ 2201 struct filedesc *fdp; 2202 struct filedescent *fde; 2203 struct file *fp; 2204 int i; 2205 2206 fdp = td->td_proc->p_fd; 2207 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2208 FILEDESC_XLOCK(fdp); 2209 for (i = 0; i <= fdp->fd_lastfile; i++) { 2210 fde = &fdp->fd_ofiles[i]; 2211 fp = fde->fde_file; 2212 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2213 (fde->fde_flags & UF_EXCLOSE))) { 2214 fdfree(fdp, i); 2215 (void) closefp(fdp, i, fp, td, 0); 2216 /* closefp() drops the FILEDESC lock. */ 2217 FILEDESC_XLOCK(fdp); 2218 } 2219 } 2220 FILEDESC_XUNLOCK(fdp); 2221} 2222 2223/* 2224 * It is unsafe for set[ug]id processes to be started with file 2225 * descriptors 0..2 closed, as these descriptors are given implicit 2226 * significance in the Standard C library. fdcheckstd() will create a 2227 * descriptor referencing /dev/null for each of stdin, stdout, and 2228 * stderr that is not already open. 2229 */ 2230int 2231fdcheckstd(struct thread *td) 2232{ 2233 struct filedesc *fdp; 2234 register_t retval, save; 2235 int i, error, devnull; 2236 2237 fdp = td->td_proc->p_fd; 2238 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2239 devnull = -1; 2240 error = 0; 2241 for (i = 0; i < 3; i++) { 2242 if (fdp->fd_ofiles[i].fde_file != NULL) 2243 continue; 2244 if (devnull < 0) { 2245 save = td->td_retval[0]; 2246 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2247 O_RDWR, 0); 2248 devnull = td->td_retval[0]; 2249 td->td_retval[0] = save; 2250 if (error) 2251 break; 2252 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2253 } else { 2254 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2255 if (error != 0) 2256 break; 2257 } 2258 } 2259 return (error); 2260} 2261 2262/* 2263 * Internal form of close. Decrement reference count on file structure. 2264 * Note: td may be NULL when closing a file that was being passed in a 2265 * message. 2266 * 2267 * XXXRW: Giant is not required for the caller, but often will be held; this 2268 * makes it moderately likely the Giant will be recursed in the VFS case. 2269 */ 2270int 2271closef(struct file *fp, struct thread *td) 2272{ 2273 struct vnode *vp; 2274 struct flock lf; 2275 struct filedesc_to_leader *fdtol; 2276 struct filedesc *fdp; 2277 2278 /* 2279 * POSIX record locking dictates that any close releases ALL 2280 * locks owned by this process. This is handled by setting 2281 * a flag in the unlock to free ONLY locks obeying POSIX 2282 * semantics, and not to free BSD-style file locks. 2283 * If the descriptor was in a message, POSIX-style locks 2284 * aren't passed with the descriptor, and the thread pointer 2285 * will be NULL. Callers should be careful only to pass a 2286 * NULL thread pointer when there really is no owning 2287 * context that might have locks, or the locks will be 2288 * leaked. 2289 */ 2290 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2291 vp = fp->f_vnode; 2292 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2293 lf.l_whence = SEEK_SET; 2294 lf.l_start = 0; 2295 lf.l_len = 0; 2296 lf.l_type = F_UNLCK; 2297 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2298 F_UNLCK, &lf, F_POSIX); 2299 } 2300 fdtol = td->td_proc->p_fdtol; 2301 if (fdtol != NULL) { 2302 /* 2303 * Handle special case where file descriptor table is 2304 * shared between multiple process leaders. 2305 */ 2306 fdp = td->td_proc->p_fd; 2307 FILEDESC_XLOCK(fdp); 2308 for (fdtol = fdtol->fdl_next; 2309 fdtol != td->td_proc->p_fdtol; 2310 fdtol = fdtol->fdl_next) { 2311 if ((fdtol->fdl_leader->p_flag & 2312 P_ADVLOCK) == 0) 2313 continue; 2314 fdtol->fdl_holdcount++; 2315 FILEDESC_XUNLOCK(fdp); 2316 lf.l_whence = SEEK_SET; 2317 lf.l_start = 0; 2318 lf.l_len = 0; 2319 lf.l_type = F_UNLCK; 2320 vp = fp->f_vnode; 2321 (void) VOP_ADVLOCK(vp, 2322 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2323 F_POSIX); 2324 FILEDESC_XLOCK(fdp); 2325 fdtol->fdl_holdcount--; 2326 if (fdtol->fdl_holdcount == 0 && 2327 fdtol->fdl_wakeup != 0) { 2328 fdtol->fdl_wakeup = 0; 2329 wakeup(fdtol); 2330 } 2331 } 2332 FILEDESC_XUNLOCK(fdp); 2333 } 2334 } 2335 return (fdrop(fp, td)); 2336} 2337 2338/* 2339 * Initialize the file pointer with the specified properties. 2340 * 2341 * The ops are set with release semantics to be certain that the flags, type, 2342 * and data are visible when ops is. This is to prevent ops methods from being 2343 * called with bad data. 2344 */ 2345void 2346finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2347{ 2348 fp->f_data = data; 2349 fp->f_flag = flag; 2350 fp->f_type = type; 2351 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2352} 2353 2354int 2355fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2356 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2357{ 2358#ifdef CAPABILITIES 2359 struct filedescent fde; 2360#endif 2361 struct file *fp; 2362 u_int count; 2363#ifdef CAPABILITIES 2364 seq_t seq; 2365 cap_rights_t haverights; 2366 int error; 2367#endif 2368 2369 /* 2370 * Avoid reads reordering and then a first access to the 2371 * fdp->fd_ofiles table which could result in OOB operation. 2372 */ 2373 if (fd < 0 || fd >= atomic_load_acq_int(&fdp->fd_nfiles)) 2374 return (EBADF); 2375 /* 2376 * Fetch the descriptor locklessly. We avoid fdrop() races by 2377 * never raising a refcount above 0. To accomplish this we have 2378 * to use a cmpset loop rather than an atomic_add. The descriptor 2379 * must be re-verified once we acquire a reference to be certain 2380 * that the identity is still correct and we did not lose a race 2381 * due to preemption. 2382 */ 2383 for (;;) { 2384#ifdef CAPABILITIES 2385 seq = seq_read(fd_seq(fdp, fd)); 2386 fde = fdp->fd_ofiles[fd]; 2387 if (!seq_consistent(fd_seq(fdp, fd), seq)) { 2388 cpu_spinwait(); 2389 continue; 2390 } 2391 fp = fde.fde_file; 2392#else 2393 fp = fdp->fd_ofiles[fd].fde_file; 2394#endif 2395 if (fp == NULL) 2396 return (EBADF); 2397#ifdef CAPABILITIES 2398 haverights = *cap_rights_fde(&fde); 2399 if (needrightsp != NULL) { 2400 error = cap_check(&haverights, needrightsp); 2401 if (error != 0) 2402 return (error); 2403 if (cap_rights_is_set(needrightsp, CAP_FCNTL)) { 2404 error = cap_fcntl_check_fde(&fde, needfcntl); 2405 if (error != 0) 2406 return (error); 2407 } 2408 } 2409#endif 2410 count = fp->f_count; 2411 if (count == 0) 2412 continue; 2413 /* 2414 * Use an acquire barrier to prevent caching of fd_ofiles 2415 * so it is refreshed for verification. 2416 */ 2417 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2418 continue; 2419#ifdef CAPABILITIES 2420 if (seq_consistent_nomb(fd_seq(fdp, fd), seq)) 2421#else 2422 if (fp == fdp->fd_ofiles[fd].fde_file) 2423#endif 2424 break; 2425 fdrop(fp, curthread); 2426 } 2427 *fpp = fp; 2428 if (haverightsp != NULL) { 2429#ifdef CAPABILITIES 2430 *haverightsp = haverights; 2431#else 2432 CAP_ALL(haverightsp); 2433#endif 2434 } 2435 return (0); 2436} 2437 2438/* 2439 * Extract the file pointer associated with the specified descriptor for the 2440 * current user process. 2441 * 2442 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2443 * returned. 2444 * 2445 * File's rights will be checked against the capability rights mask. 2446 * 2447 * If an error occured the non-zero error is returned and *fpp is set to 2448 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2449 * responsible for fdrop(). 2450 */ 2451static __inline int 2452_fget(struct thread *td, int fd, struct file **fpp, int flags, 2453 cap_rights_t *needrightsp, u_char *maxprotp) 2454{ 2455 struct filedesc *fdp; 2456 struct file *fp; 2457 cap_rights_t haverights, needrights; 2458 int error; 2459 2460 *fpp = NULL; 2461 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2462 return (EBADF); 2463 if (needrightsp != NULL) 2464 needrights = *needrightsp; 2465 else 2466 cap_rights_init(&needrights); 2467 if (maxprotp != NULL) 2468 cap_rights_set(&needrights, CAP_MMAP); 2469 error = fget_unlocked(fdp, fd, &needrights, 0, &fp, &haverights); 2470 if (error != 0) 2471 return (error); 2472 if (fp->f_ops == &badfileops) { 2473 fdrop(fp, td); 2474 return (EBADF); 2475 } 2476 2477#ifdef CAPABILITIES 2478 /* 2479 * If requested, convert capability rights to access flags. 2480 */ 2481 if (maxprotp != NULL) 2482 *maxprotp = cap_rights_to_vmprot(&haverights); 2483#else /* !CAPABILITIES */ 2484 if (maxprotp != NULL) 2485 *maxprotp = VM_PROT_ALL; 2486#endif /* CAPABILITIES */ 2487 2488 /* 2489 * FREAD and FWRITE failure return EBADF as per POSIX. 2490 */ 2491 error = 0; 2492 switch (flags) { 2493 case FREAD: 2494 case FWRITE: 2495 if ((fp->f_flag & flags) == 0) 2496 error = EBADF; 2497 break; 2498 case FEXEC: 2499 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2500 ((fp->f_flag & FWRITE) != 0)) 2501 error = EBADF; 2502 break; 2503 case 0: 2504 break; 2505 default: 2506 KASSERT(0, ("wrong flags")); 2507 } 2508 2509 if (error != 0) { 2510 fdrop(fp, td); 2511 return (error); 2512 } 2513 2514 *fpp = fp; 2515 return (0); 2516} 2517 2518int 2519fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2520{ 2521 2522 return(_fget(td, fd, fpp, 0, rightsp, NULL)); 2523} 2524 2525int 2526fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2527 struct file **fpp) 2528{ 2529 2530 return (_fget(td, fd, fpp, 0, rightsp, maxprotp)); 2531} 2532 2533int 2534fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2535{ 2536 2537 return(_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2538} 2539 2540int 2541fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2542{ 2543 2544 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2545} 2546 2547/* 2548 * Like fget() but loads the underlying vnode, or returns an error if the 2549 * descriptor does not represent a vnode. Note that pipes use vnodes but 2550 * never have VM objects. The returned vnode will be vref()'d. 2551 * 2552 * XXX: what about the unused flags ? 2553 */ 2554static __inline int 2555_fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2556 struct vnode **vpp) 2557{ 2558 struct file *fp; 2559 int error; 2560 2561 *vpp = NULL; 2562 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2563 if (error != 0) 2564 return (error); 2565 if (fp->f_vnode == NULL) { 2566 error = EINVAL; 2567 } else { 2568 *vpp = fp->f_vnode; 2569 vref(*vpp); 2570 } 2571 fdrop(fp, td); 2572 2573 return (error); 2574} 2575 2576int 2577fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2578{ 2579 2580 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2581} 2582 2583int 2584fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2585 struct filecaps *havecaps, struct vnode **vpp) 2586{ 2587 struct filedesc *fdp; 2588 struct file *fp; 2589#ifdef CAPABILITIES 2590 int error; 2591#endif 2592 2593 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2594 return (EBADF); 2595 2596 fp = fget_locked(fdp, fd); 2597 if (fp == NULL || fp->f_ops == &badfileops) 2598 return (EBADF); 2599 2600#ifdef CAPABILITIES 2601 if (needrightsp != NULL) { 2602 error = cap_check(cap_rights(fdp, fd), needrightsp); 2603 if (error != 0) 2604 return (error); 2605 } 2606#endif 2607 2608 if (fp->f_vnode == NULL) 2609 return (EINVAL); 2610 2611 *vpp = fp->f_vnode; 2612 vref(*vpp); 2613 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2614 2615 return (0); 2616} 2617 2618int 2619fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2620{ 2621 2622 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2623} 2624 2625int 2626fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2627{ 2628 2629 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2630} 2631 2632#ifdef notyet 2633int 2634fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2635 struct vnode **vpp) 2636{ 2637 2638 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2639} 2640#endif 2641 2642/* 2643 * Like fget() but loads the underlying socket, or returns an error if the 2644 * descriptor does not represent a socket. 2645 * 2646 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2647 * in the future. 2648 * 2649 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2650 * on their file descriptor reference to prevent the socket from being free'd 2651 * during use. 2652 */ 2653int 2654fgetsock(struct thread *td, int fd, cap_rights_t *rightsp, struct socket **spp, 2655 u_int *fflagp) 2656{ 2657 struct file *fp; 2658 int error; 2659 2660 *spp = NULL; 2661 if (fflagp != NULL) 2662 *fflagp = 0; 2663 if ((error = _fget(td, fd, &fp, 0, rightsp, NULL)) != 0) 2664 return (error); 2665 if (fp->f_type != DTYPE_SOCKET) { 2666 error = ENOTSOCK; 2667 } else { 2668 *spp = fp->f_data; 2669 if (fflagp) 2670 *fflagp = fp->f_flag; 2671 SOCK_LOCK(*spp); 2672 soref(*spp); 2673 SOCK_UNLOCK(*spp); 2674 } 2675 fdrop(fp, td); 2676 2677 return (error); 2678} 2679 2680/* 2681 * Drop the reference count on the socket and XXX release the SX lock in the 2682 * future. The last reference closes the socket. 2683 * 2684 * Note: fputsock() is deprecated, see comment for fgetsock(). 2685 */ 2686void 2687fputsock(struct socket *so) 2688{ 2689 2690 ACCEPT_LOCK(); 2691 SOCK_LOCK(so); 2692 CURVNET_SET(so->so_vnet); 2693 sorele(so); 2694 CURVNET_RESTORE(); 2695} 2696 2697/* 2698 * Handle the last reference to a file being closed. 2699 */ 2700int 2701_fdrop(struct file *fp, struct thread *td) 2702{ 2703 int error; 2704 2705 error = 0; 2706 if (fp->f_count != 0) 2707 panic("fdrop: count %d", fp->f_count); 2708 if (fp->f_ops != &badfileops) 2709 error = fo_close(fp, td); 2710 atomic_subtract_int(&openfiles, 1); 2711 crfree(fp->f_cred); 2712 free(fp->f_advice, M_FADVISE); 2713 uma_zfree(file_zone, fp); 2714 2715 return (error); 2716} 2717 2718/* 2719 * Apply an advisory lock on a file descriptor. 2720 * 2721 * Just attempt to get a record lock of the requested type on the entire file 2722 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2723 */ 2724#ifndef _SYS_SYSPROTO_H_ 2725struct flock_args { 2726 int fd; 2727 int how; 2728}; 2729#endif 2730/* ARGSUSED */ 2731int 2732sys_flock(struct thread *td, struct flock_args *uap) 2733{ 2734 struct file *fp; 2735 struct vnode *vp; 2736 struct flock lf; 2737 cap_rights_t rights; 2738 int error; 2739 2740 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2741 if (error != 0) 2742 return (error); 2743 if (fp->f_type != DTYPE_VNODE) { 2744 fdrop(fp, td); 2745 return (EOPNOTSUPP); 2746 } 2747 2748 vp = fp->f_vnode; 2749 lf.l_whence = SEEK_SET; 2750 lf.l_start = 0; 2751 lf.l_len = 0; 2752 if (uap->how & LOCK_UN) { 2753 lf.l_type = F_UNLCK; 2754 atomic_clear_int(&fp->f_flag, FHASLOCK); 2755 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2756 goto done2; 2757 } 2758 if (uap->how & LOCK_EX) 2759 lf.l_type = F_WRLCK; 2760 else if (uap->how & LOCK_SH) 2761 lf.l_type = F_RDLCK; 2762 else { 2763 error = EBADF; 2764 goto done2; 2765 } 2766 atomic_set_int(&fp->f_flag, FHASLOCK); 2767 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2768 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2769done2: 2770 fdrop(fp, td); 2771 return (error); 2772} 2773/* 2774 * Duplicate the specified descriptor to a free descriptor. 2775 */ 2776int 2777dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2778 int openerror, int *indxp) 2779{ 2780 struct filedescent *newfde, *oldfde; 2781 struct file *fp; 2782 int error, indx; 2783 2784 KASSERT(openerror == ENODEV || openerror == ENXIO, 2785 ("unexpected error %d in %s", openerror, __func__)); 2786 2787 /* 2788 * If the to-be-dup'd fd number is greater than the allowed number 2789 * of file descriptors, or the fd to be dup'd has already been 2790 * closed, then reject. 2791 */ 2792 FILEDESC_XLOCK(fdp); 2793 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2794 FILEDESC_XUNLOCK(fdp); 2795 return (EBADF); 2796 } 2797 2798 error = fdalloc(td, 0, &indx); 2799 if (error != 0) { 2800 FILEDESC_XUNLOCK(fdp); 2801 return (error); 2802 } 2803 2804 /* 2805 * There are two cases of interest here. 2806 * 2807 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2808 * 2809 * For ENXIO steal away the file structure from (dfd) and store it in 2810 * (indx). (dfd) is effectively closed by this operation. 2811 */ 2812 switch (openerror) { 2813 case ENODEV: 2814 /* 2815 * Check that the mode the file is being opened for is a 2816 * subset of the mode of the existing descriptor. 2817 */ 2818 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2819 fdunused(fdp, indx); 2820 FILEDESC_XUNLOCK(fdp); 2821 return (EACCES); 2822 } 2823 fhold(fp); 2824 newfde = &fdp->fd_ofiles[indx]; 2825 oldfde = &fdp->fd_ofiles[dfd]; 2826#ifdef CAPABILITIES 2827 seq_write_begin(&newfde->fde_seq); 2828#endif 2829 memcpy(newfde, oldfde, fde_change_size); 2830 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 2831#ifdef CAPABILITIES 2832 seq_write_end(&newfde->fde_seq); 2833#endif 2834 break; 2835 case ENXIO: 2836 /* 2837 * Steal away the file pointer from dfd and stuff it into indx. 2838 */ 2839 newfde = &fdp->fd_ofiles[indx]; 2840 oldfde = &fdp->fd_ofiles[dfd]; 2841#ifdef CAPABILITIES 2842 seq_write_begin(&newfde->fde_seq); 2843#endif 2844 memcpy(newfde, oldfde, fde_change_size); 2845 bzero(oldfde, fde_change_size); 2846 fdunused(fdp, dfd); 2847#ifdef CAPABILITIES 2848 seq_write_end(&newfde->fde_seq); 2849#endif 2850 break; 2851 } 2852 FILEDESC_XUNLOCK(fdp); 2853 *indxp = indx; 2854 return (0); 2855} 2856 2857/* 2858 * Scan all active processes and prisons to see if any of them have a current 2859 * or root directory of `olddp'. If so, replace them with the new mount point. 2860 */ 2861void 2862mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2863{ 2864 struct filedesc *fdp; 2865 struct prison *pr; 2866 struct proc *p; 2867 int nrele; 2868 2869 if (vrefcnt(olddp) == 1) 2870 return; 2871 nrele = 0; 2872 sx_slock(&allproc_lock); 2873 FOREACH_PROC_IN_SYSTEM(p) { 2874 fdp = fdhold(p); 2875 if (fdp == NULL) 2876 continue; 2877 FILEDESC_XLOCK(fdp); 2878 if (fdp->fd_cdir == olddp) { 2879 vref(newdp); 2880 fdp->fd_cdir = newdp; 2881 nrele++; 2882 } 2883 if (fdp->fd_rdir == olddp) { 2884 vref(newdp); 2885 fdp->fd_rdir = newdp; 2886 nrele++; 2887 } 2888 if (fdp->fd_jdir == olddp) { 2889 vref(newdp); 2890 fdp->fd_jdir = newdp; 2891 nrele++; 2892 } 2893 FILEDESC_XUNLOCK(fdp); 2894 fddrop(fdp); 2895 } 2896 sx_sunlock(&allproc_lock); 2897 if (rootvnode == olddp) { 2898 vref(newdp); 2899 rootvnode = newdp; 2900 nrele++; 2901 } 2902 mtx_lock(&prison0.pr_mtx); 2903 if (prison0.pr_root == olddp) { 2904 vref(newdp); 2905 prison0.pr_root = newdp; 2906 nrele++; 2907 } 2908 mtx_unlock(&prison0.pr_mtx); 2909 sx_slock(&allprison_lock); 2910 TAILQ_FOREACH(pr, &allprison, pr_list) { 2911 mtx_lock(&pr->pr_mtx); 2912 if (pr->pr_root == olddp) { 2913 vref(newdp); 2914 pr->pr_root = newdp; 2915 nrele++; 2916 } 2917 mtx_unlock(&pr->pr_mtx); 2918 } 2919 sx_sunlock(&allprison_lock); 2920 while (nrele--) 2921 vrele(olddp); 2922} 2923 2924struct filedesc_to_leader * 2925filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2926{ 2927 struct filedesc_to_leader *fdtol; 2928 2929 fdtol = malloc(sizeof(struct filedesc_to_leader), 2930 M_FILEDESC_TO_LEADER, 2931 M_WAITOK); 2932 fdtol->fdl_refcount = 1; 2933 fdtol->fdl_holdcount = 0; 2934 fdtol->fdl_wakeup = 0; 2935 fdtol->fdl_leader = leader; 2936 if (old != NULL) { 2937 FILEDESC_XLOCK(fdp); 2938 fdtol->fdl_next = old->fdl_next; 2939 fdtol->fdl_prev = old; 2940 old->fdl_next = fdtol; 2941 fdtol->fdl_next->fdl_prev = fdtol; 2942 FILEDESC_XUNLOCK(fdp); 2943 } else { 2944 fdtol->fdl_next = fdtol; 2945 fdtol->fdl_prev = fdtol; 2946 } 2947 return (fdtol); 2948} 2949 2950/* 2951 * Get file structures globally. 2952 */ 2953static int 2954sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2955{ 2956 struct xfile xf; 2957 struct filedesc *fdp; 2958 struct file *fp; 2959 struct proc *p; 2960 int error, n; 2961 2962 error = sysctl_wire_old_buffer(req, 0); 2963 if (error != 0) 2964 return (error); 2965 if (req->oldptr == NULL) { 2966 n = 0; 2967 sx_slock(&allproc_lock); 2968 FOREACH_PROC_IN_SYSTEM(p) { 2969 if (p->p_state == PRS_NEW) 2970 continue; 2971 fdp = fdhold(p); 2972 if (fdp == NULL) 2973 continue; 2974 /* overestimates sparse tables. */ 2975 if (fdp->fd_lastfile > 0) 2976 n += fdp->fd_lastfile; 2977 fddrop(fdp); 2978 } 2979 sx_sunlock(&allproc_lock); 2980 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2981 } 2982 error = 0; 2983 bzero(&xf, sizeof(xf)); 2984 xf.xf_size = sizeof(xf); 2985 sx_slock(&allproc_lock); 2986 FOREACH_PROC_IN_SYSTEM(p) { 2987 PROC_LOCK(p); 2988 if (p->p_state == PRS_NEW) { 2989 PROC_UNLOCK(p); 2990 continue; 2991 } 2992 if (p_cansee(req->td, p) != 0) { 2993 PROC_UNLOCK(p); 2994 continue; 2995 } 2996 xf.xf_pid = p->p_pid; 2997 xf.xf_uid = p->p_ucred->cr_uid; 2998 PROC_UNLOCK(p); 2999 fdp = fdhold(p); 3000 if (fdp == NULL) 3001 continue; 3002 FILEDESC_SLOCK(fdp); 3003 for (n = 0; fdp->fd_refcnt > 0 && n <= fdp->fd_lastfile; ++n) { 3004 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3005 continue; 3006 xf.xf_fd = n; 3007 xf.xf_file = fp; 3008 xf.xf_data = fp->f_data; 3009 xf.xf_vnode = fp->f_vnode; 3010 xf.xf_type = fp->f_type; 3011 xf.xf_count = fp->f_count; 3012 xf.xf_msgcount = 0; 3013 xf.xf_offset = foffset_get(fp); 3014 xf.xf_flag = fp->f_flag; 3015 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 3016 if (error) 3017 break; 3018 } 3019 FILEDESC_SUNLOCK(fdp); 3020 fddrop(fdp); 3021 if (error) 3022 break; 3023 } 3024 sx_sunlock(&allproc_lock); 3025 return (error); 3026} 3027 3028SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE, 3029 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 3030 3031#ifdef KINFO_OFILE_SIZE 3032CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 3033#endif 3034 3035#ifdef COMPAT_FREEBSD7 3036static int 3037export_vnode_for_osysctl(struct vnode *vp, int type, 3038 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 3039{ 3040 int error; 3041 char *fullpath, *freepath; 3042 3043 bzero(kif, sizeof(*kif)); 3044 kif->kf_structsize = sizeof(*kif); 3045 3046 vref(vp); 3047 kif->kf_fd = type; 3048 kif->kf_type = KF_TYPE_VNODE; 3049 /* This function only handles directories. */ 3050 if (vp->v_type != VDIR) { 3051 vrele(vp); 3052 return (ENOTDIR); 3053 } 3054 kif->kf_vnode_type = KF_VTYPE_VDIR; 3055 3056 /* 3057 * This is not a true file descriptor, so we set a bogus refcount 3058 * and offset to indicate these fields should be ignored. 3059 */ 3060 kif->kf_ref_count = -1; 3061 kif->kf_offset = -1; 3062 3063 freepath = NULL; 3064 fullpath = "-"; 3065 FILEDESC_SUNLOCK(fdp); 3066 vn_fullpath(curthread, vp, &fullpath, &freepath); 3067 vrele(vp); 3068 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3069 if (freepath != NULL) 3070 free(freepath, M_TEMP); 3071 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3072 FILEDESC_SLOCK(fdp); 3073 return (error); 3074} 3075 3076/* 3077 * Get per-process file descriptors for use by procstat(1), et al. 3078 */ 3079static int 3080sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3081{ 3082 char *fullpath, *freepath; 3083 struct kinfo_ofile *kif; 3084 struct filedesc *fdp; 3085 int error, i, *name; 3086 struct shmfd *shmfd; 3087 struct socket *so; 3088 struct vnode *vp; 3089 struct ksem *ks; 3090 struct file *fp; 3091 struct proc *p; 3092 struct tty *tp; 3093 3094 name = (int *)arg1; 3095 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3096 if (error != 0) 3097 return (error); 3098 fdp = fdhold(p); 3099 PROC_UNLOCK(p); 3100 if (fdp == NULL) 3101 return (ENOENT); 3102 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3103 FILEDESC_SLOCK(fdp); 3104 if (fdp->fd_cdir != NULL) 3105 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3106 fdp, req); 3107 if (fdp->fd_rdir != NULL) 3108 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3109 fdp, req); 3110 if (fdp->fd_jdir != NULL) 3111 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3112 fdp, req); 3113 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3114 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3115 continue; 3116 bzero(kif, sizeof(*kif)); 3117 kif->kf_structsize = sizeof(*kif); 3118 ks = NULL; 3119 vp = NULL; 3120 so = NULL; 3121 tp = NULL; 3122 shmfd = NULL; 3123 kif->kf_fd = i; 3124 3125 switch (fp->f_type) { 3126 case DTYPE_VNODE: 3127 kif->kf_type = KF_TYPE_VNODE; 3128 vp = fp->f_vnode; 3129 break; 3130 3131 case DTYPE_SOCKET: 3132 kif->kf_type = KF_TYPE_SOCKET; 3133 so = fp->f_data; 3134 break; 3135 3136 case DTYPE_PIPE: 3137 kif->kf_type = KF_TYPE_PIPE; 3138 break; 3139 3140 case DTYPE_FIFO: 3141 kif->kf_type = KF_TYPE_FIFO; 3142 vp = fp->f_vnode; 3143 break; 3144 3145 case DTYPE_KQUEUE: 3146 kif->kf_type = KF_TYPE_KQUEUE; 3147 break; 3148 3149 case DTYPE_CRYPTO: 3150 kif->kf_type = KF_TYPE_CRYPTO; 3151 break; 3152 3153 case DTYPE_MQUEUE: 3154 kif->kf_type = KF_TYPE_MQUEUE; 3155 break; 3156 3157 case DTYPE_SHM: 3158 kif->kf_type = KF_TYPE_SHM; 3159 shmfd = fp->f_data; 3160 break; 3161 3162 case DTYPE_SEM: 3163 kif->kf_type = KF_TYPE_SEM; 3164 ks = fp->f_data; 3165 break; 3166 3167 case DTYPE_PTS: 3168 kif->kf_type = KF_TYPE_PTS; 3169 tp = fp->f_data; 3170 break; 3171 3172#ifdef PROCDESC 3173 case DTYPE_PROCDESC: 3174 kif->kf_type = KF_TYPE_PROCDESC; 3175 break; 3176#endif 3177 3178 default: 3179 kif->kf_type = KF_TYPE_UNKNOWN; 3180 break; 3181 } 3182 kif->kf_ref_count = fp->f_count; 3183 if (fp->f_flag & FREAD) 3184 kif->kf_flags |= KF_FLAG_READ; 3185 if (fp->f_flag & FWRITE) 3186 kif->kf_flags |= KF_FLAG_WRITE; 3187 if (fp->f_flag & FAPPEND) 3188 kif->kf_flags |= KF_FLAG_APPEND; 3189 if (fp->f_flag & FASYNC) 3190 kif->kf_flags |= KF_FLAG_ASYNC; 3191 if (fp->f_flag & FFSYNC) 3192 kif->kf_flags |= KF_FLAG_FSYNC; 3193 if (fp->f_flag & FNONBLOCK) 3194 kif->kf_flags |= KF_FLAG_NONBLOCK; 3195 if (fp->f_flag & O_DIRECT) 3196 kif->kf_flags |= KF_FLAG_DIRECT; 3197 if (fp->f_flag & FHASLOCK) 3198 kif->kf_flags |= KF_FLAG_HASLOCK; 3199 kif->kf_offset = foffset_get(fp); 3200 if (vp != NULL) { 3201 vref(vp); 3202 switch (vp->v_type) { 3203 case VNON: 3204 kif->kf_vnode_type = KF_VTYPE_VNON; 3205 break; 3206 case VREG: 3207 kif->kf_vnode_type = KF_VTYPE_VREG; 3208 break; 3209 case VDIR: 3210 kif->kf_vnode_type = KF_VTYPE_VDIR; 3211 break; 3212 case VBLK: 3213 kif->kf_vnode_type = KF_VTYPE_VBLK; 3214 break; 3215 case VCHR: 3216 kif->kf_vnode_type = KF_VTYPE_VCHR; 3217 break; 3218 case VLNK: 3219 kif->kf_vnode_type = KF_VTYPE_VLNK; 3220 break; 3221 case VSOCK: 3222 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3223 break; 3224 case VFIFO: 3225 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3226 break; 3227 case VBAD: 3228 kif->kf_vnode_type = KF_VTYPE_VBAD; 3229 break; 3230 default: 3231 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3232 break; 3233 } 3234 /* 3235 * It is OK to drop the filedesc lock here as we will 3236 * re-validate and re-evaluate its properties when 3237 * the loop continues. 3238 */ 3239 freepath = NULL; 3240 fullpath = "-"; 3241 FILEDESC_SUNLOCK(fdp); 3242 vn_fullpath(curthread, vp, &fullpath, &freepath); 3243 vrele(vp); 3244 strlcpy(kif->kf_path, fullpath, 3245 sizeof(kif->kf_path)); 3246 if (freepath != NULL) 3247 free(freepath, M_TEMP); 3248 FILEDESC_SLOCK(fdp); 3249 } 3250 if (so != NULL) { 3251 struct sockaddr *sa; 3252 3253 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3254 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3255 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3256 free(sa, M_SONAME); 3257 } 3258 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3259 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3260 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3261 free(sa, M_SONAME); 3262 } 3263 kif->kf_sock_domain = 3264 so->so_proto->pr_domain->dom_family; 3265 kif->kf_sock_type = so->so_type; 3266 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3267 } 3268 if (tp != NULL) { 3269 strlcpy(kif->kf_path, tty_devname(tp), 3270 sizeof(kif->kf_path)); 3271 } 3272 if (shmfd != NULL) 3273 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3274 if (ks != NULL && ksem_info != NULL) 3275 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL); 3276 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3277 if (error) 3278 break; 3279 } 3280 FILEDESC_SUNLOCK(fdp); 3281 fddrop(fdp); 3282 free(kif, M_TEMP); 3283 return (0); 3284} 3285 3286static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, 3287 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc, 3288 "Process ofiledesc entries"); 3289#endif /* COMPAT_FREEBSD7 */ 3290 3291#ifdef KINFO_FILE_SIZE 3292CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3293#endif 3294 3295struct export_fd_buf { 3296 struct filedesc *fdp; 3297 struct sbuf *sb; 3298 ssize_t remainder; 3299 struct kinfo_file kif; 3300}; 3301 3302static int 3303export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt, 3304 int64_t offset, cap_rights_t *rightsp, struct export_fd_buf *efbuf) 3305{ 3306 struct { 3307 int fflag; 3308 int kf_fflag; 3309 } fflags_table[] = { 3310 { FAPPEND, KF_FLAG_APPEND }, 3311 { FASYNC, KF_FLAG_ASYNC }, 3312 { FFSYNC, KF_FLAG_FSYNC }, 3313 { FHASLOCK, KF_FLAG_HASLOCK }, 3314 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3315 { FREAD, KF_FLAG_READ }, 3316 { FWRITE, KF_FLAG_WRITE }, 3317 { O_CREAT, KF_FLAG_CREAT }, 3318 { O_DIRECT, KF_FLAG_DIRECT }, 3319 { O_EXCL, KF_FLAG_EXCL }, 3320 { O_EXEC, KF_FLAG_EXEC }, 3321 { O_EXLOCK, KF_FLAG_EXLOCK }, 3322 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3323 { O_SHLOCK, KF_FLAG_SHLOCK }, 3324 { O_TRUNC, KF_FLAG_TRUNC } 3325 }; 3326#define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3327 struct kinfo_file *kif; 3328 struct vnode *vp; 3329 int error, locked; 3330 unsigned int i; 3331 3332 if (efbuf->remainder == 0) 3333 return (0); 3334 kif = &efbuf->kif; 3335 bzero(kif, sizeof(*kif)); 3336 locked = efbuf->fdp != NULL; 3337 switch (type) { 3338 case KF_TYPE_FIFO: 3339 case KF_TYPE_VNODE: 3340 if (locked) { 3341 FILEDESC_SUNLOCK(efbuf->fdp); 3342 locked = 0; 3343 } 3344 vp = (struct vnode *)data; 3345 error = fill_vnode_info(vp, kif); 3346 vrele(vp); 3347 break; 3348 case KF_TYPE_SOCKET: 3349 error = fill_socket_info((struct socket *)data, kif); 3350 break; 3351 case KF_TYPE_PIPE: 3352 error = fill_pipe_info((struct pipe *)data, kif); 3353 break; 3354 case KF_TYPE_PTS: 3355 error = fill_pts_info((struct tty *)data, kif); 3356 break; 3357 case KF_TYPE_PROCDESC: 3358 error = fill_procdesc_info((struct procdesc *)data, kif); 3359 break; 3360 case KF_TYPE_SEM: 3361 error = fill_sem_info((struct file *)data, kif); 3362 break; 3363 case KF_TYPE_SHM: 3364 error = fill_shm_info((struct file *)data, kif); 3365 break; 3366 default: 3367 error = 0; 3368 } 3369 if (error == 0) 3370 kif->kf_status |= KF_ATTR_VALID; 3371 3372 /* 3373 * Translate file access flags. 3374 */ 3375 for (i = 0; i < NFFLAGS; i++) 3376 if (fflags & fflags_table[i].fflag) 3377 kif->kf_flags |= fflags_table[i].kf_fflag; 3378 if (rightsp != NULL) 3379 kif->kf_cap_rights = *rightsp; 3380 else 3381 cap_rights_init(&kif->kf_cap_rights); 3382 kif->kf_fd = fd; 3383 kif->kf_type = type; 3384 kif->kf_ref_count = refcnt; 3385 kif->kf_offset = offset; 3386 /* Pack record size down */ 3387 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3388 strlen(kif->kf_path) + 1; 3389 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3390 if (efbuf->remainder != -1) { 3391 if (efbuf->remainder < kif->kf_structsize) { 3392 /* Terminate export. */ 3393 efbuf->remainder = 0; 3394 if (efbuf->fdp != NULL && !locked) 3395 FILEDESC_SLOCK(efbuf->fdp); 3396 return (0); 3397 } 3398 efbuf->remainder -= kif->kf_structsize; 3399 } 3400 if (locked) 3401 FILEDESC_SUNLOCK(efbuf->fdp); 3402 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) == 0 ? 0 : ENOMEM; 3403 if (efbuf->fdp != NULL) 3404 FILEDESC_SLOCK(efbuf->fdp); 3405 return (error); 3406} 3407 3408/* 3409 * Store a process file descriptor information to sbuf. 3410 * 3411 * Takes a locked proc as argument, and returns with the proc unlocked. 3412 */ 3413int 3414kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3415{ 3416 struct file *fp; 3417 struct filedesc *fdp; 3418 struct export_fd_buf *efbuf; 3419 struct vnode *cttyvp, *textvp, *tracevp; 3420 int64_t offset; 3421 void *data; 3422 int error, i; 3423 int type, refcnt, fflags; 3424 cap_rights_t rights; 3425 3426 PROC_LOCK_ASSERT(p, MA_OWNED); 3427 3428 /* ktrace vnode */ 3429 tracevp = p->p_tracevp; 3430 if (tracevp != NULL) 3431 vref(tracevp); 3432 /* text vnode */ 3433 textvp = p->p_textvp; 3434 if (textvp != NULL) 3435 vref(textvp); 3436 /* Controlling tty. */ 3437 cttyvp = NULL; 3438 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3439 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3440 if (cttyvp != NULL) 3441 vref(cttyvp); 3442 } 3443 fdp = fdhold(p); 3444 PROC_UNLOCK(p); 3445 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3446 efbuf->fdp = NULL; 3447 efbuf->sb = sb; 3448 efbuf->remainder = maxlen; 3449 if (tracevp != NULL) 3450 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3451 FREAD | FWRITE, -1, -1, NULL, efbuf); 3452 if (textvp != NULL) 3453 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3454 FREAD, -1, -1, NULL, efbuf); 3455 if (cttyvp != NULL) 3456 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3457 FREAD | FWRITE, -1, -1, NULL, efbuf); 3458 error = 0; 3459 if (fdp == NULL) 3460 goto fail; 3461 efbuf->fdp = fdp; 3462 FILEDESC_SLOCK(fdp); 3463 /* working directory */ 3464 if (fdp->fd_cdir != NULL) { 3465 vref(fdp->fd_cdir); 3466 data = fdp->fd_cdir; 3467 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3468 FREAD, -1, -1, NULL, efbuf); 3469 } 3470 /* root directory */ 3471 if (fdp->fd_rdir != NULL) { 3472 vref(fdp->fd_rdir); 3473 data = fdp->fd_rdir; 3474 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3475 FREAD, -1, -1, NULL, efbuf); 3476 } 3477 /* jail directory */ 3478 if (fdp->fd_jdir != NULL) { 3479 vref(fdp->fd_jdir); 3480 data = fdp->fd_jdir; 3481 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3482 FREAD, -1, -1, NULL, efbuf); 3483 } 3484 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) { 3485 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3486 continue; 3487 data = NULL; 3488#ifdef CAPABILITIES 3489 rights = *cap_rights(fdp, i); 3490#else /* !CAPABILITIES */ 3491 cap_rights_init(&rights); 3492#endif 3493 switch (fp->f_type) { 3494 case DTYPE_VNODE: 3495 type = KF_TYPE_VNODE; 3496 vref(fp->f_vnode); 3497 data = fp->f_vnode; 3498 break; 3499 3500 case DTYPE_SOCKET: 3501 type = KF_TYPE_SOCKET; 3502 data = fp->f_data; 3503 break; 3504 3505 case DTYPE_PIPE: 3506 type = KF_TYPE_PIPE; 3507 data = fp->f_data; 3508 break; 3509 3510 case DTYPE_FIFO: 3511 type = KF_TYPE_FIFO; 3512 vref(fp->f_vnode); 3513 data = fp->f_vnode; 3514 break; 3515 3516 case DTYPE_KQUEUE: 3517 type = KF_TYPE_KQUEUE; 3518 break; 3519 3520 case DTYPE_CRYPTO: 3521 type = KF_TYPE_CRYPTO; 3522 break; 3523 3524 case DTYPE_MQUEUE: 3525 type = KF_TYPE_MQUEUE; 3526 break; 3527 3528 case DTYPE_SHM: 3529 type = KF_TYPE_SHM; 3530 data = fp; 3531 break; 3532 3533 case DTYPE_SEM: 3534 type = KF_TYPE_SEM; 3535 data = fp; 3536 break; 3537 3538 case DTYPE_PTS: 3539 type = KF_TYPE_PTS; 3540 data = fp->f_data; 3541 break; 3542 3543#ifdef PROCDESC 3544 case DTYPE_PROCDESC: 3545 type = KF_TYPE_PROCDESC; 3546 data = fp->f_data; 3547 break; 3548#endif 3549 3550 default: 3551 type = KF_TYPE_UNKNOWN; 3552 break; 3553 } 3554 refcnt = fp->f_count; 3555 fflags = fp->f_flag; 3556 offset = foffset_get(fp); 3557 3558 /* 3559 * Create sysctl entry. 3560 * It is OK to drop the filedesc lock here as we will 3561 * re-validate and re-evaluate its properties when 3562 * the loop continues. 3563 */ 3564 error = export_fd_to_sb(data, type, i, fflags, refcnt, 3565 offset, &rights, efbuf); 3566 if (error != 0) 3567 break; 3568 } 3569 FILEDESC_SUNLOCK(fdp); 3570 fddrop(fdp); 3571fail: 3572 free(efbuf, M_TEMP); 3573 return (error); 3574} 3575 3576#define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3577 3578/* 3579 * Get per-process file descriptors for use by procstat(1), et al. 3580 */ 3581static int 3582sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3583{ 3584 struct sbuf sb; 3585 struct proc *p; 3586 ssize_t maxlen; 3587 int error, error2, *name; 3588 3589 name = (int *)arg1; 3590 3591 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3592 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p); 3593 if (error != 0) { 3594 sbuf_delete(&sb); 3595 return (error); 3596 } 3597 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3598 error = kern_proc_filedesc_out(p, &sb, maxlen); 3599 error2 = sbuf_finish(&sb); 3600 sbuf_delete(&sb); 3601 return (error != 0 ? error : error2); 3602} 3603 3604int 3605vntype_to_kinfo(int vtype) 3606{ 3607 struct { 3608 int vtype; 3609 int kf_vtype; 3610 } vtypes_table[] = { 3611 { VBAD, KF_VTYPE_VBAD }, 3612 { VBLK, KF_VTYPE_VBLK }, 3613 { VCHR, KF_VTYPE_VCHR }, 3614 { VDIR, KF_VTYPE_VDIR }, 3615 { VFIFO, KF_VTYPE_VFIFO }, 3616 { VLNK, KF_VTYPE_VLNK }, 3617 { VNON, KF_VTYPE_VNON }, 3618 { VREG, KF_VTYPE_VREG }, 3619 { VSOCK, KF_VTYPE_VSOCK } 3620 }; 3621#define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3622 unsigned int i; 3623 3624 /* 3625 * Perform vtype translation. 3626 */ 3627 for (i = 0; i < NVTYPES; i++) 3628 if (vtypes_table[i].vtype == vtype) 3629 break; 3630 if (i < NVTYPES) 3631 return (vtypes_table[i].kf_vtype); 3632 3633 return (KF_VTYPE_UNKNOWN); 3634} 3635 3636static int 3637fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3638{ 3639 struct vattr va; 3640 char *fullpath, *freepath; 3641 int error; 3642 3643 if (vp == NULL) 3644 return (1); 3645 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3646 freepath = NULL; 3647 fullpath = "-"; 3648 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3649 if (error == 0) { 3650 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3651 } 3652 if (freepath != NULL) 3653 free(freepath, M_TEMP); 3654 3655 /* 3656 * Retrieve vnode attributes. 3657 */ 3658 va.va_fsid = VNOVAL; 3659 va.va_rdev = NODEV; 3660 vn_lock(vp, LK_SHARED | LK_RETRY); 3661 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3662 VOP_UNLOCK(vp, 0); 3663 if (error != 0) 3664 return (error); 3665 if (va.va_fsid != VNOVAL) 3666 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3667 else 3668 kif->kf_un.kf_file.kf_file_fsid = 3669 vp->v_mount->mnt_stat.f_fsid.val[0]; 3670 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3671 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3672 kif->kf_un.kf_file.kf_file_size = va.va_size; 3673 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3674 return (0); 3675} 3676 3677static int 3678fill_socket_info(struct socket *so, struct kinfo_file *kif) 3679{ 3680 struct sockaddr *sa; 3681 struct inpcb *inpcb; 3682 struct unpcb *unpcb; 3683 int error; 3684 3685 if (so == NULL) 3686 return (1); 3687 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3688 kif->kf_sock_type = so->so_type; 3689 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3690 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3691 switch(kif->kf_sock_domain) { 3692 case AF_INET: 3693 case AF_INET6: 3694 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3695 if (so->so_pcb != NULL) { 3696 inpcb = (struct inpcb *)(so->so_pcb); 3697 kif->kf_un.kf_sock.kf_sock_inpcb = 3698 (uintptr_t)inpcb->inp_ppcb; 3699 } 3700 } 3701 break; 3702 case AF_UNIX: 3703 if (so->so_pcb != NULL) { 3704 unpcb = (struct unpcb *)(so->so_pcb); 3705 if (unpcb->unp_conn) { 3706 kif->kf_un.kf_sock.kf_sock_unpconn = 3707 (uintptr_t)unpcb->unp_conn; 3708 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3709 so->so_rcv.sb_state; 3710 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3711 so->so_snd.sb_state; 3712 } 3713 } 3714 break; 3715 } 3716 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3717 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3718 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3719 free(sa, M_SONAME); 3720 } 3721 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3722 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3723 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3724 free(sa, M_SONAME); 3725 } 3726 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3727 sizeof(kif->kf_path)); 3728 return (0); 3729} 3730 3731static int 3732fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3733{ 3734 3735 if (tp == NULL) 3736 return (1); 3737 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3738 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3739 return (0); 3740} 3741 3742static int 3743fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3744{ 3745 3746 if (pi == NULL) 3747 return (1); 3748 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3749 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3750 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3751 return (0); 3752} 3753 3754static int 3755fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3756{ 3757 3758 if (pdp == NULL) 3759 return (1); 3760 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3761 return (0); 3762} 3763 3764static int 3765fill_sem_info(struct file *fp, struct kinfo_file *kif) 3766{ 3767 struct thread *td; 3768 struct stat sb; 3769 3770 td = curthread; 3771 if (fp->f_data == NULL) 3772 return (1); 3773 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3774 return (1); 3775 if (ksem_info == NULL) 3776 return (1); 3777 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path), 3778 &kif->kf_un.kf_sem.kf_sem_value); 3779 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode; 3780 return (0); 3781} 3782 3783static int 3784fill_shm_info(struct file *fp, struct kinfo_file *kif) 3785{ 3786 struct thread *td; 3787 struct stat sb; 3788 3789 td = curthread; 3790 if (fp->f_data == NULL) 3791 return (1); 3792 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3793 return (1); 3794 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3795 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3796 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3797 return (0); 3798} 3799 3800static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, 3801 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc, 3802 "Process filedesc entries"); 3803 3804#ifdef DDB 3805/* 3806 * For the purposes of debugging, generate a human-readable string for the 3807 * file type. 3808 */ 3809static const char * 3810file_type_to_name(short type) 3811{ 3812 3813 switch (type) { 3814 case 0: 3815 return ("zero"); 3816 case DTYPE_VNODE: 3817 return ("vnod"); 3818 case DTYPE_SOCKET: 3819 return ("sock"); 3820 case DTYPE_PIPE: 3821 return ("pipe"); 3822 case DTYPE_FIFO: 3823 return ("fifo"); 3824 case DTYPE_KQUEUE: 3825 return ("kque"); 3826 case DTYPE_CRYPTO: 3827 return ("crpt"); 3828 case DTYPE_MQUEUE: 3829 return ("mque"); 3830 case DTYPE_SHM: 3831 return ("shm"); 3832 case DTYPE_SEM: 3833 return ("ksem"); 3834 default: 3835 return ("unkn"); 3836 } 3837} 3838 3839/* 3840 * For the purposes of debugging, identify a process (if any, perhaps one of 3841 * many) that references the passed file in its file descriptor array. Return 3842 * NULL if none. 3843 */ 3844static struct proc * 3845file_to_first_proc(struct file *fp) 3846{ 3847 struct filedesc *fdp; 3848 struct proc *p; 3849 int n; 3850 3851 FOREACH_PROC_IN_SYSTEM(p) { 3852 if (p->p_state == PRS_NEW) 3853 continue; 3854 fdp = p->p_fd; 3855 if (fdp == NULL) 3856 continue; 3857 for (n = 0; n <= fdp->fd_lastfile; n++) { 3858 if (fp == fdp->fd_ofiles[n].fde_file) 3859 return (p); 3860 } 3861 } 3862 return (NULL); 3863} 3864 3865static void 3866db_print_file(struct file *fp, int header) 3867{ 3868 struct proc *p; 3869 3870 if (header) 3871 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3872 "File", "Type", "Data", "Flag", "GCFl", "Count", 3873 "MCount", "Vnode", "FPID", "FCmd"); 3874 p = file_to_first_proc(fp); 3875 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3876 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3877 0, fp->f_count, 0, fp->f_vnode, 3878 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3879} 3880 3881DB_SHOW_COMMAND(file, db_show_file) 3882{ 3883 struct file *fp; 3884 3885 if (!have_addr) { 3886 db_printf("usage: show file <addr>\n"); 3887 return; 3888 } 3889 fp = (struct file *)addr; 3890 db_print_file(fp, 1); 3891} 3892 3893DB_SHOW_COMMAND(files, db_show_files) 3894{ 3895 struct filedesc *fdp; 3896 struct file *fp; 3897 struct proc *p; 3898 int header; 3899 int n; 3900 3901 header = 1; 3902 FOREACH_PROC_IN_SYSTEM(p) { 3903 if (p->p_state == PRS_NEW) 3904 continue; 3905 if ((fdp = p->p_fd) == NULL) 3906 continue; 3907 for (n = 0; n <= fdp->fd_lastfile; ++n) { 3908 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3909 continue; 3910 db_print_file(fp, header); 3911 header = 0; 3912 } 3913 } 3914} 3915#endif 3916 3917SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3918 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3919 3920SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3921 &maxfiles, 0, "Maximum number of files"); 3922 3923SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3924 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3925 3926/* ARGSUSED*/ 3927static void 3928filelistinit(void *dummy) 3929{ 3930 3931 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3932 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3933 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3934 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3935} 3936SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3937 3938/*-------------------------------------------------------------------*/ 3939 3940static int 3941badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3942 int flags, struct thread *td) 3943{ 3944 3945 return (EBADF); 3946} 3947 3948static int 3949badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3950 struct thread *td) 3951{ 3952 3953 return (EINVAL); 3954} 3955 3956static int 3957badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3958 struct thread *td) 3959{ 3960 3961 return (EBADF); 3962} 3963 3964static int 3965badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3966 struct thread *td) 3967{ 3968 3969 return (0); 3970} 3971 3972static int 3973badfo_kqfilter(struct file *fp, struct knote *kn) 3974{ 3975 3976 return (EBADF); 3977} 3978 3979static int 3980badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3981 struct thread *td) 3982{ 3983 3984 return (EBADF); 3985} 3986 3987static int 3988badfo_close(struct file *fp, struct thread *td) 3989{ 3990 3991 return (EBADF); 3992} 3993 3994static int 3995badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3996 struct thread *td) 3997{ 3998 3999 return (EBADF); 4000} 4001 4002static int 4003badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4004 struct thread *td) 4005{ 4006 4007 return (EBADF); 4008} 4009 4010static int 4011badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4012 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4013 int kflags, struct thread *td) 4014{ 4015 4016 return (EBADF); 4017} 4018 4019struct fileops badfileops = { 4020 .fo_read = badfo_readwrite, 4021 .fo_write = badfo_readwrite, 4022 .fo_truncate = badfo_truncate, 4023 .fo_ioctl = badfo_ioctl, 4024 .fo_poll = badfo_poll, 4025 .fo_kqfilter = badfo_kqfilter, 4026 .fo_stat = badfo_stat, 4027 .fo_close = badfo_close, 4028 .fo_chmod = badfo_chmod, 4029 .fo_chown = badfo_chown, 4030 .fo_sendfile = badfo_sendfile, 4031}; 4032 4033int 4034invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 4035 struct thread *td) 4036{ 4037 4038 return (EINVAL); 4039} 4040 4041int 4042invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 4043 struct thread *td) 4044{ 4045 4046 return (EINVAL); 4047} 4048 4049int 4050invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 4051 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 4052 int kflags, struct thread *td) 4053{ 4054 4055 return (EINVAL); 4056} 4057 4058/*-------------------------------------------------------------------*/ 4059 4060/* 4061 * File Descriptor pseudo-device driver (/dev/fd/). 4062 * 4063 * Opening minor device N dup()s the file (if any) connected to file 4064 * descriptor N belonging to the calling process. Note that this driver 4065 * consists of only the ``open()'' routine, because all subsequent 4066 * references to this file will be direct to the other driver. 4067 * 4068 * XXX: we could give this one a cloning event handler if necessary. 4069 */ 4070 4071/* ARGSUSED */ 4072static int 4073fdopen(struct cdev *dev, int mode, int type, struct thread *td) 4074{ 4075 4076 /* 4077 * XXX Kludge: set curthread->td_dupfd to contain the value of the 4078 * the file descriptor being sought for duplication. The error 4079 * return ensures that the vnode for this device will be released 4080 * by vn_open. Open will detect this special error and take the 4081 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 4082 * will simply report the error. 4083 */ 4084 td->td_dupfd = dev2unit(dev); 4085 return (ENODEV); 4086} 4087 4088static struct cdevsw fildesc_cdevsw = { 4089 .d_version = D_VERSION, 4090 .d_open = fdopen, 4091 .d_name = "FD", 4092}; 4093 4094static void 4095fildesc_drvinit(void *unused) 4096{ 4097 struct cdev *dev; 4098 4099 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4100 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4101 make_dev_alias(dev, "stdin"); 4102 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4103 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4104 make_dev_alias(dev, "stdout"); 4105 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4106 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4107 make_dev_alias(dev, "stderr"); 4108} 4109 4110SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4111