kern_descrip.c revision 262692
1/*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 35 */ 36 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD: stable/10/sys/kern/kern_descrip.c 262692 2014-03-02 16:04:27Z bdrewery $"); 39 40#include "opt_capsicum.h" 41#include "opt_compat.h" 42#include "opt_ddb.h" 43#include "opt_ktrace.h" 44#include "opt_procdesc.h" 45 46#include <sys/param.h> 47#include <sys/systm.h> 48 49#include <sys/capability.h> 50#include <sys/conf.h> 51#include <sys/domain.h> 52#include <sys/fcntl.h> 53#include <sys/file.h> 54#include <sys/filedesc.h> 55#include <sys/filio.h> 56#include <sys/jail.h> 57#include <sys/kernel.h> 58#include <sys/ksem.h> 59#include <sys/limits.h> 60#include <sys/lock.h> 61#include <sys/malloc.h> 62#include <sys/mman.h> 63#include <sys/mount.h> 64#include <sys/mqueue.h> 65#include <sys/mutex.h> 66#include <sys/namei.h> 67#include <sys/selinfo.h> 68#include <sys/pipe.h> 69#include <sys/priv.h> 70#include <sys/proc.h> 71#include <sys/procdesc.h> 72#include <sys/protosw.h> 73#include <sys/racct.h> 74#include <sys/resourcevar.h> 75#include <sys/sbuf.h> 76#include <sys/signalvar.h> 77#include <sys/socketvar.h> 78#include <sys/stat.h> 79#include <sys/sx.h> 80#include <sys/syscallsubr.h> 81#include <sys/sysctl.h> 82#include <sys/sysproto.h> 83#include <sys/tty.h> 84#include <sys/unistd.h> 85#include <sys/un.h> 86#include <sys/unpcb.h> 87#include <sys/user.h> 88#include <sys/vnode.h> 89#ifdef KTRACE 90#include <sys/ktrace.h> 91#endif 92 93#include <net/vnet.h> 94 95#include <netinet/in.h> 96#include <netinet/in_pcb.h> 97 98#include <security/audit/audit.h> 99 100#include <vm/uma.h> 101#include <vm/vm.h> 102 103#include <ddb/ddb.h> 104 105static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); 106static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", 107 "file desc to leader structures"); 108static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); 109MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities"); 110 111MALLOC_DECLARE(M_FADVISE); 112 113static uma_zone_t file_zone; 114 115void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value); 116 117static int closefp(struct filedesc *fdp, int fd, struct file *fp, 118 struct thread *td, int holdleaders); 119static int fd_first_free(struct filedesc *fdp, int low, int size); 120static int fd_last_used(struct filedesc *fdp, int size); 121static void fdgrowtable(struct filedesc *fdp, int nfd); 122static void fdgrowtable_exp(struct filedesc *fdp, int nfd); 123static void fdunused(struct filedesc *fdp, int fd); 124static void fdused(struct filedesc *fdp, int fd); 125static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); 126static int fill_procdesc_info(struct procdesc *pdp, 127 struct kinfo_file *kif); 128static int fill_pts_info(struct tty *tp, struct kinfo_file *kif); 129static int fill_sem_info(struct file *fp, struct kinfo_file *kif); 130static int fill_shm_info(struct file *fp, struct kinfo_file *kif); 131static int fill_socket_info(struct socket *so, struct kinfo_file *kif); 132static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); 133static int getmaxfd(struct proc *p); 134 135/* 136 * Each process has: 137 * 138 * - An array of open file descriptors (fd_ofiles) 139 * - An array of file flags (fd_ofileflags) 140 * - A bitmap recording which descriptors are in use (fd_map) 141 * 142 * A process starts out with NDFILE descriptors. The value of NDFILE has 143 * been selected based the historical limit of 20 open files, and an 144 * assumption that the majority of processes, especially short-lived 145 * processes like shells, will never need more. 146 * 147 * If this initial allocation is exhausted, a larger descriptor table and 148 * map are allocated dynamically, and the pointers in the process's struct 149 * filedesc are updated to point to those. This is repeated every time 150 * the process runs out of file descriptors (provided it hasn't hit its 151 * resource limit). 152 * 153 * Since threads may hold references to individual descriptor table 154 * entries, the tables are never freed. Instead, they are placed on a 155 * linked list and freed only when the struct filedesc is released. 156 */ 157#define NDFILE 20 158#define NDSLOTSIZE sizeof(NDSLOTTYPE) 159#define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) 160#define NDSLOT(x) ((x) / NDENTRIES) 161#define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) 162#define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) 163 164/* 165 * SLIST entry used to keep track of ofiles which must be reclaimed when 166 * the process exits. 167 */ 168struct freetable { 169 struct filedescent *ft_table; 170 SLIST_ENTRY(freetable) ft_next; 171}; 172 173/* 174 * Initial allocation: a filedesc structure + the head of SLIST used to 175 * keep track of old ofiles + enough space for NDFILE descriptors. 176 */ 177struct filedesc0 { 178 struct filedesc fd_fd; 179 SLIST_HEAD(, freetable) fd_free; 180 struct filedescent fd_dfiles[NDFILE]; 181 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; 182}; 183 184/* 185 * Descriptor management. 186 */ 187volatile int openfiles; /* actual number of open files */ 188struct mtx sigio_lock; /* mtx to protect pointers to sigio */ 189void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); 190 191/* A mutex to protect the association between a proc and filedesc. */ 192static struct mtx fdesc_mtx; 193 194/* 195 * If low >= size, just return low. Otherwise find the first zero bit in the 196 * given bitmap, starting at low and not exceeding size - 1. Return size if 197 * not found. 198 */ 199static int 200fd_first_free(struct filedesc *fdp, int low, int size) 201{ 202 NDSLOTTYPE *map = fdp->fd_map; 203 NDSLOTTYPE mask; 204 int off, maxoff; 205 206 if (low >= size) 207 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 */ 299static inline void 300fdfree(struct filedesc *fdp, int fd) 301{ 302 struct filedescent *fde; 303 304 fde = &fdp->fd_ofiles[fd]; 305 filecaps_free(&fde->fde_caps); 306 bzero(fde, sizeof(*fde)); 307 fdunused(fdp, fd); 308} 309 310/* 311 * System calls on descriptors. 312 */ 313#ifndef _SYS_SYSPROTO_H_ 314struct getdtablesize_args { 315 int dummy; 316}; 317#endif 318/* ARGSUSED */ 319int 320sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) 321{ 322 struct proc *p = td->td_proc; 323 uint64_t lim; 324 325 PROC_LOCK(p); 326 td->td_retval[0] = 327 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 328 lim = racct_get_limit(td->td_proc, RACCT_NOFILE); 329 PROC_UNLOCK(p); 330 if (lim < td->td_retval[0]) 331 td->td_retval[0] = lim; 332 return (0); 333} 334 335/* 336 * Duplicate a file descriptor to a particular value. 337 * 338 * Note: keep in mind that a potential race condition exists when closing 339 * descriptors from a shared descriptor table (via rfork). 340 */ 341#ifndef _SYS_SYSPROTO_H_ 342struct dup2_args { 343 u_int from; 344 u_int to; 345}; 346#endif 347/* ARGSUSED */ 348int 349sys_dup2(struct thread *td, struct dup2_args *uap) 350{ 351 352 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, 353 td->td_retval)); 354} 355 356/* 357 * Duplicate a file descriptor. 358 */ 359#ifndef _SYS_SYSPROTO_H_ 360struct dup_args { 361 u_int fd; 362}; 363#endif 364/* ARGSUSED */ 365int 366sys_dup(struct thread *td, struct dup_args *uap) 367{ 368 369 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); 370} 371 372/* 373 * The file control system call. 374 */ 375#ifndef _SYS_SYSPROTO_H_ 376struct fcntl_args { 377 int fd; 378 int cmd; 379 long arg; 380}; 381#endif 382/* ARGSUSED */ 383int 384sys_fcntl(struct thread *td, struct fcntl_args *uap) 385{ 386 struct flock fl; 387 struct __oflock ofl; 388 intptr_t arg; 389 int error; 390 int cmd; 391 392 error = 0; 393 cmd = uap->cmd; 394 switch (uap->cmd) { 395 case F_OGETLK: 396 case F_OSETLK: 397 case F_OSETLKW: 398 /* 399 * Convert old flock structure to new. 400 */ 401 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); 402 fl.l_start = ofl.l_start; 403 fl.l_len = ofl.l_len; 404 fl.l_pid = ofl.l_pid; 405 fl.l_type = ofl.l_type; 406 fl.l_whence = ofl.l_whence; 407 fl.l_sysid = 0; 408 409 switch (uap->cmd) { 410 case F_OGETLK: 411 cmd = F_GETLK; 412 break; 413 case F_OSETLK: 414 cmd = F_SETLK; 415 break; 416 case F_OSETLKW: 417 cmd = F_SETLKW; 418 break; 419 } 420 arg = (intptr_t)&fl; 421 break; 422 case F_GETLK: 423 case F_SETLK: 424 case F_SETLKW: 425 case F_SETLK_REMOTE: 426 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); 427 arg = (intptr_t)&fl; 428 break; 429 default: 430 arg = uap->arg; 431 break; 432 } 433 if (error) 434 return (error); 435 error = kern_fcntl(td, uap->fd, cmd, arg); 436 if (error) 437 return (error); 438 if (uap->cmd == F_OGETLK) { 439 ofl.l_start = fl.l_start; 440 ofl.l_len = fl.l_len; 441 ofl.l_pid = fl.l_pid; 442 ofl.l_type = fl.l_type; 443 ofl.l_whence = fl.l_whence; 444 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); 445 } else if (uap->cmd == F_GETLK) { 446 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); 447 } 448 return (error); 449} 450 451int 452kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) 453{ 454 struct filedesc *fdp; 455 struct flock *flp; 456 struct file *fp, *fp2; 457 struct filedescent *fde; 458 struct proc *p; 459 struct vnode *vp; 460 cap_rights_t rights; 461 int error, flg, tmp; 462 u_int old, new; 463 uint64_t bsize; 464 off_t foffset; 465 466 error = 0; 467 flg = F_POSIX; 468 p = td->td_proc; 469 fdp = p->p_fd; 470 471 switch (cmd) { 472 case F_DUPFD: 473 tmp = arg; 474 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); 475 break; 476 477 case F_DUPFD_CLOEXEC: 478 tmp = arg; 479 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, 480 td->td_retval); 481 break; 482 483 case F_DUP2FD: 484 tmp = arg; 485 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); 486 break; 487 488 case F_DUP2FD_CLOEXEC: 489 tmp = arg; 490 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, 491 td->td_retval); 492 break; 493 494 case F_GETFD: 495 FILEDESC_SLOCK(fdp); 496 if ((fp = fget_locked(fdp, fd)) == NULL) { 497 FILEDESC_SUNLOCK(fdp); 498 error = EBADF; 499 break; 500 } 501 fde = &fdp->fd_ofiles[fd]; 502 td->td_retval[0] = 503 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0; 504 FILEDESC_SUNLOCK(fdp); 505 break; 506 507 case F_SETFD: 508 FILEDESC_XLOCK(fdp); 509 if ((fp = fget_locked(fdp, fd)) == NULL) { 510 FILEDESC_XUNLOCK(fdp); 511 error = EBADF; 512 break; 513 } 514 fde = &fdp->fd_ofiles[fd]; 515 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) | 516 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); 517 FILEDESC_XUNLOCK(fdp); 518 break; 519 520 case F_GETFL: 521 error = fget_unlocked(fdp, fd, 522 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp, NULL); 523 if (error != 0) 524 break; 525 td->td_retval[0] = OFLAGS(fp->f_flag); 526 fdrop(fp, td); 527 break; 528 529 case F_SETFL: 530 error = fget_unlocked(fdp, fd, 531 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp, NULL); 532 if (error != 0) 533 break; 534 do { 535 tmp = flg = fp->f_flag; 536 tmp &= ~FCNTLFLAGS; 537 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; 538 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); 539 tmp = fp->f_flag & FNONBLOCK; 540 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 541 if (error != 0) { 542 fdrop(fp, td); 543 break; 544 } 545 tmp = fp->f_flag & FASYNC; 546 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); 547 if (error == 0) { 548 fdrop(fp, td); 549 break; 550 } 551 atomic_clear_int(&fp->f_flag, FNONBLOCK); 552 tmp = 0; 553 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); 554 fdrop(fp, td); 555 break; 556 557 case F_GETOWN: 558 error = fget_unlocked(fdp, fd, 559 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp, NULL); 560 if (error != 0) 561 break; 562 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); 563 if (error == 0) 564 td->td_retval[0] = tmp; 565 fdrop(fp, td); 566 break; 567 568 case F_SETOWN: 569 error = fget_unlocked(fdp, fd, 570 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp, NULL); 571 if (error != 0) 572 break; 573 tmp = arg; 574 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); 575 fdrop(fp, td); 576 break; 577 578 case F_SETLK_REMOTE: 579 error = priv_check(td, PRIV_NFS_LOCKD); 580 if (error) 581 return (error); 582 flg = F_REMOTE; 583 goto do_setlk; 584 585 case F_SETLKW: 586 flg |= F_WAIT; 587 /* FALLTHROUGH F_SETLK */ 588 589 case F_SETLK: 590 do_setlk: 591 cap_rights_init(&rights, CAP_FLOCK); 592 error = fget_unlocked(fdp, fd, &rights, 0, &fp, NULL); 593 if (error != 0) 594 break; 595 if (fp->f_type != DTYPE_VNODE) { 596 error = EBADF; 597 fdrop(fp, td); 598 break; 599 } 600 601 flp = (struct flock *)arg; 602 if (flp->l_whence == SEEK_CUR) { 603 foffset = foffset_get(fp); 604 if (foffset < 0 || 605 (flp->l_start > 0 && 606 foffset > OFF_MAX - flp->l_start)) { 607 FILEDESC_SUNLOCK(fdp); 608 error = EOVERFLOW; 609 fdrop(fp, td); 610 break; 611 } 612 flp->l_start += foffset; 613 } 614 615 vp = fp->f_vnode; 616 switch (flp->l_type) { 617 case F_RDLCK: 618 if ((fp->f_flag & FREAD) == 0) { 619 error = EBADF; 620 break; 621 } 622 PROC_LOCK(p->p_leader); 623 p->p_leader->p_flag |= P_ADVLOCK; 624 PROC_UNLOCK(p->p_leader); 625 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 626 flp, flg); 627 break; 628 case F_WRLCK: 629 if ((fp->f_flag & FWRITE) == 0) { 630 error = EBADF; 631 break; 632 } 633 PROC_LOCK(p->p_leader); 634 p->p_leader->p_flag |= P_ADVLOCK; 635 PROC_UNLOCK(p->p_leader); 636 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, 637 flp, flg); 638 break; 639 case F_UNLCK: 640 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, 641 flp, flg); 642 break; 643 case F_UNLCKSYS: 644 /* 645 * Temporary api for testing remote lock 646 * infrastructure. 647 */ 648 if (flg != F_REMOTE) { 649 error = EINVAL; 650 break; 651 } 652 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 653 F_UNLCKSYS, flp, flg); 654 break; 655 default: 656 error = EINVAL; 657 break; 658 } 659 if (error != 0 || flp->l_type == F_UNLCK || 660 flp->l_type == F_UNLCKSYS) { 661 fdrop(fp, td); 662 break; 663 } 664 665 /* 666 * Check for a race with close. 667 * 668 * The vnode is now advisory locked (or unlocked, but this case 669 * is not really important) as the caller requested. 670 * We had to drop the filedesc lock, so we need to recheck if 671 * the descriptor is still valid, because if it was closed 672 * in the meantime we need to remove advisory lock from the 673 * vnode - close on any descriptor leading to an advisory 674 * locked vnode, removes that lock. 675 * We will return 0 on purpose in that case, as the result of 676 * successful advisory lock might have been externally visible 677 * already. This is fine - effectively we pretend to the caller 678 * that the closing thread was a bit slower and that the 679 * advisory lock succeeded before the close. 680 */ 681 error = fget_unlocked(fdp, fd, &rights, 0, &fp2, NULL); 682 if (error != 0) { 683 fdrop(fp, td); 684 break; 685 } 686 if (fp != fp2) { 687 flp->l_whence = SEEK_SET; 688 flp->l_start = 0; 689 flp->l_len = 0; 690 flp->l_type = F_UNLCK; 691 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, 692 F_UNLCK, flp, F_POSIX); 693 } 694 fdrop(fp, td); 695 fdrop(fp2, td); 696 break; 697 698 case F_GETLK: 699 error = fget_unlocked(fdp, fd, 700 cap_rights_init(&rights, CAP_FLOCK), 0, &fp, NULL); 701 if (error != 0) 702 break; 703 if (fp->f_type != DTYPE_VNODE) { 704 error = EBADF; 705 fdrop(fp, td); 706 break; 707 } 708 flp = (struct flock *)arg; 709 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && 710 flp->l_type != F_UNLCK) { 711 error = EINVAL; 712 fdrop(fp, td); 713 break; 714 } 715 if (flp->l_whence == SEEK_CUR) { 716 foffset = foffset_get(fp); 717 if ((flp->l_start > 0 && 718 foffset > OFF_MAX - flp->l_start) || 719 (flp->l_start < 0 && 720 foffset < OFF_MIN - flp->l_start)) { 721 FILEDESC_SUNLOCK(fdp); 722 error = EOVERFLOW; 723 fdrop(fp, td); 724 break; 725 } 726 flp->l_start += foffset; 727 } 728 vp = fp->f_vnode; 729 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, 730 F_POSIX); 731 fdrop(fp, td); 732 break; 733 734 case F_RDAHEAD: 735 arg = arg ? 128 * 1024: 0; 736 /* FALLTHROUGH */ 737 case F_READAHEAD: 738 error = fget_unlocked(fdp, fd, NULL, 0, &fp, NULL); 739 if (error != 0) 740 break; 741 if (fp->f_type != DTYPE_VNODE) { 742 fdrop(fp, td); 743 error = EBADF; 744 break; 745 } 746 if (arg >= 0) { 747 vp = fp->f_vnode; 748 error = vn_lock(vp, LK_SHARED); 749 if (error != 0) { 750 fdrop(fp, td); 751 break; 752 } 753 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; 754 VOP_UNLOCK(vp, 0); 755 fp->f_seqcount = (arg + bsize - 1) / bsize; 756 do { 757 new = old = fp->f_flag; 758 new |= FRDAHEAD; 759 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 760 } else { 761 do { 762 new = old = fp->f_flag; 763 new &= ~FRDAHEAD; 764 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); 765 } 766 fdrop(fp, td); 767 break; 768 769 default: 770 error = EINVAL; 771 break; 772 } 773 return (error); 774} 775 776static int 777getmaxfd(struct proc *p) 778{ 779 int maxfd; 780 781 PROC_LOCK(p); 782 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); 783 PROC_UNLOCK(p); 784 785 return (maxfd); 786} 787 788/* 789 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). 790 */ 791int 792do_dup(struct thread *td, int flags, int old, int new, 793 register_t *retval) 794{ 795 struct filedesc *fdp; 796 struct filedescent *oldfde, *newfde; 797 struct proc *p; 798 struct file *fp; 799 struct file *delfp; 800 int error, maxfd; 801 802 p = td->td_proc; 803 fdp = p->p_fd; 804 805 /* 806 * Verify we have a valid descriptor to dup from and possibly to 807 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should 808 * return EINVAL when the new descriptor is out of bounds. 809 */ 810 if (old < 0) 811 return (EBADF); 812 if (new < 0) 813 return (flags & DUP_FCNTL ? EINVAL : EBADF); 814 maxfd = getmaxfd(p); 815 if (new >= maxfd) 816 return (flags & DUP_FCNTL ? EINVAL : EBADF); 817 818 FILEDESC_XLOCK(fdp); 819 if (fget_locked(fdp, old) == NULL) { 820 FILEDESC_XUNLOCK(fdp); 821 return (EBADF); 822 } 823 oldfde = &fdp->fd_ofiles[old]; 824 if (flags & DUP_FIXED && old == new) { 825 *retval = new; 826 if (flags & DUP_CLOEXEC) 827 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE; 828 FILEDESC_XUNLOCK(fdp); 829 return (0); 830 } 831 fp = oldfde->fde_file; 832 fhold(fp); 833 834 /* 835 * If the caller specified a file descriptor, make sure the file 836 * table is large enough to hold it, and grab it. Otherwise, just 837 * allocate a new descriptor the usual way. 838 */ 839 if (flags & DUP_FIXED) { 840 if (new >= fdp->fd_nfiles) { 841 /* 842 * The resource limits are here instead of e.g. 843 * fdalloc(), because the file descriptor table may be 844 * shared between processes, so we can't really use 845 * racct_add()/racct_sub(). Instead of counting the 846 * number of actually allocated descriptors, just put 847 * the limit on the size of the file descriptor table. 848 */ 849#ifdef RACCT 850 PROC_LOCK(p); 851 error = racct_set(p, RACCT_NOFILE, new + 1); 852 PROC_UNLOCK(p); 853 if (error != 0) { 854 FILEDESC_XUNLOCK(fdp); 855 fdrop(fp, td); 856 return (EMFILE); 857 } 858#endif 859 fdgrowtable_exp(fdp, new + 1); 860 oldfde = &fdp->fd_ofiles[old]; 861 } 862 newfde = &fdp->fd_ofiles[new]; 863 if (newfde->fde_file == NULL) 864 fdused(fdp, new); 865 } else { 866 if ((error = fdalloc(td, new, &new)) != 0) { 867 FILEDESC_XUNLOCK(fdp); 868 fdrop(fp, td); 869 return (error); 870 } 871 newfde = &fdp->fd_ofiles[new]; 872 } 873 874 KASSERT(fp == oldfde->fde_file, ("old fd has been modified")); 875 KASSERT(old != new, ("new fd is same as old")); 876 877 delfp = newfde->fde_file; 878 879 /* 880 * Duplicate the source descriptor. 881 */ 882 filecaps_free(&newfde->fde_caps); 883 *newfde = *oldfde; 884 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps); 885 if ((flags & DUP_CLOEXEC) != 0) 886 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE; 887 else 888 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE; 889 if (new > fdp->fd_lastfile) 890 fdp->fd_lastfile = new; 891 *retval = new; 892 893 if (delfp != NULL) { 894 (void) closefp(fdp, new, delfp, td, 1); 895 /* closefp() drops the FILEDESC lock for us. */ 896 } else { 897 FILEDESC_XUNLOCK(fdp); 898 } 899 900 return (0); 901} 902 903/* 904 * If sigio is on the list associated with a process or process group, 905 * disable signalling from the device, remove sigio from the list and 906 * free sigio. 907 */ 908void 909funsetown(struct sigio **sigiop) 910{ 911 struct sigio *sigio; 912 913 SIGIO_LOCK(); 914 sigio = *sigiop; 915 if (sigio == NULL) { 916 SIGIO_UNLOCK(); 917 return; 918 } 919 *(sigio->sio_myref) = NULL; 920 if ((sigio)->sio_pgid < 0) { 921 struct pgrp *pg = (sigio)->sio_pgrp; 922 PGRP_LOCK(pg); 923 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, 924 sigio, sio_pgsigio); 925 PGRP_UNLOCK(pg); 926 } else { 927 struct proc *p = (sigio)->sio_proc; 928 PROC_LOCK(p); 929 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, 930 sigio, sio_pgsigio); 931 PROC_UNLOCK(p); 932 } 933 SIGIO_UNLOCK(); 934 crfree(sigio->sio_ucred); 935 free(sigio, M_SIGIO); 936} 937 938/* 939 * Free a list of sigio structures. 940 * We only need to lock the SIGIO_LOCK because we have made ourselves 941 * inaccessible to callers of fsetown and therefore do not need to lock 942 * the proc or pgrp struct for the list manipulation. 943 */ 944void 945funsetownlst(struct sigiolst *sigiolst) 946{ 947 struct proc *p; 948 struct pgrp *pg; 949 struct sigio *sigio; 950 951 sigio = SLIST_FIRST(sigiolst); 952 if (sigio == NULL) 953 return; 954 p = NULL; 955 pg = NULL; 956 957 /* 958 * Every entry of the list should belong 959 * to a single proc or pgrp. 960 */ 961 if (sigio->sio_pgid < 0) { 962 pg = sigio->sio_pgrp; 963 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); 964 } else /* if (sigio->sio_pgid > 0) */ { 965 p = sigio->sio_proc; 966 PROC_LOCK_ASSERT(p, MA_NOTOWNED); 967 } 968 969 SIGIO_LOCK(); 970 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { 971 *(sigio->sio_myref) = NULL; 972 if (pg != NULL) { 973 KASSERT(sigio->sio_pgid < 0, 974 ("Proc sigio in pgrp sigio list")); 975 KASSERT(sigio->sio_pgrp == pg, 976 ("Bogus pgrp in sigio list")); 977 PGRP_LOCK(pg); 978 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, 979 sio_pgsigio); 980 PGRP_UNLOCK(pg); 981 } else /* if (p != NULL) */ { 982 KASSERT(sigio->sio_pgid > 0, 983 ("Pgrp sigio in proc sigio list")); 984 KASSERT(sigio->sio_proc == p, 985 ("Bogus proc in sigio list")); 986 PROC_LOCK(p); 987 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, 988 sio_pgsigio); 989 PROC_UNLOCK(p); 990 } 991 SIGIO_UNLOCK(); 992 crfree(sigio->sio_ucred); 993 free(sigio, M_SIGIO); 994 SIGIO_LOCK(); 995 } 996 SIGIO_UNLOCK(); 997} 998 999/* 1000 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). 1001 * 1002 * After permission checking, add a sigio structure to the sigio list for 1003 * the process or process group. 1004 */ 1005int 1006fsetown(pid_t pgid, struct sigio **sigiop) 1007{ 1008 struct proc *proc; 1009 struct pgrp *pgrp; 1010 struct sigio *sigio; 1011 int ret; 1012 1013 if (pgid == 0) { 1014 funsetown(sigiop); 1015 return (0); 1016 } 1017 1018 ret = 0; 1019 1020 /* Allocate and fill in the new sigio out of locks. */ 1021 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); 1022 sigio->sio_pgid = pgid; 1023 sigio->sio_ucred = crhold(curthread->td_ucred); 1024 sigio->sio_myref = sigiop; 1025 1026 sx_slock(&proctree_lock); 1027 if (pgid > 0) { 1028 proc = pfind(pgid); 1029 if (proc == NULL) { 1030 ret = ESRCH; 1031 goto fail; 1032 } 1033 1034 /* 1035 * Policy - Don't allow a process to FSETOWN a process 1036 * in another session. 1037 * 1038 * Remove this test to allow maximum flexibility or 1039 * restrict FSETOWN to the current process or process 1040 * group for maximum safety. 1041 */ 1042 PROC_UNLOCK(proc); 1043 if (proc->p_session != curthread->td_proc->p_session) { 1044 ret = EPERM; 1045 goto fail; 1046 } 1047 1048 pgrp = NULL; 1049 } else /* if (pgid < 0) */ { 1050 pgrp = pgfind(-pgid); 1051 if (pgrp == NULL) { 1052 ret = ESRCH; 1053 goto fail; 1054 } 1055 PGRP_UNLOCK(pgrp); 1056 1057 /* 1058 * Policy - Don't allow a process to FSETOWN a process 1059 * in another session. 1060 * 1061 * Remove this test to allow maximum flexibility or 1062 * restrict FSETOWN to the current process or process 1063 * group for maximum safety. 1064 */ 1065 if (pgrp->pg_session != curthread->td_proc->p_session) { 1066 ret = EPERM; 1067 goto fail; 1068 } 1069 1070 proc = NULL; 1071 } 1072 funsetown(sigiop); 1073 if (pgid > 0) { 1074 PROC_LOCK(proc); 1075 /* 1076 * Since funsetownlst() is called without the proctree 1077 * locked, we need to check for P_WEXIT. 1078 * XXX: is ESRCH correct? 1079 */ 1080 if ((proc->p_flag & P_WEXIT) != 0) { 1081 PROC_UNLOCK(proc); 1082 ret = ESRCH; 1083 goto fail; 1084 } 1085 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); 1086 sigio->sio_proc = proc; 1087 PROC_UNLOCK(proc); 1088 } else { 1089 PGRP_LOCK(pgrp); 1090 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); 1091 sigio->sio_pgrp = pgrp; 1092 PGRP_UNLOCK(pgrp); 1093 } 1094 sx_sunlock(&proctree_lock); 1095 SIGIO_LOCK(); 1096 *sigiop = sigio; 1097 SIGIO_UNLOCK(); 1098 return (0); 1099 1100fail: 1101 sx_sunlock(&proctree_lock); 1102 crfree(sigio->sio_ucred); 1103 free(sigio, M_SIGIO); 1104 return (ret); 1105} 1106 1107/* 1108 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). 1109 */ 1110pid_t 1111fgetown(sigiop) 1112 struct sigio **sigiop; 1113{ 1114 pid_t pgid; 1115 1116 SIGIO_LOCK(); 1117 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; 1118 SIGIO_UNLOCK(); 1119 return (pgid); 1120} 1121 1122/* 1123 * Function drops the filedesc lock on return. 1124 */ 1125static int 1126closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, 1127 int holdleaders) 1128{ 1129 int error; 1130 1131 FILEDESC_XLOCK_ASSERT(fdp); 1132 1133 if (holdleaders) { 1134 if (td->td_proc->p_fdtol != NULL) { 1135 /* 1136 * Ask fdfree() to sleep to ensure that all relevant 1137 * process leaders can be traversed in closef(). 1138 */ 1139 fdp->fd_holdleaderscount++; 1140 } else { 1141 holdleaders = 0; 1142 } 1143 } 1144 1145 /* 1146 * We now hold the fp reference that used to be owned by the 1147 * descriptor array. We have to unlock the FILEDESC *AFTER* 1148 * knote_fdclose to prevent a race of the fd getting opened, a knote 1149 * added, and deleteing a knote for the new fd. 1150 */ 1151 knote_fdclose(td, fd); 1152 1153 /* 1154 * We need to notify mqueue if the object is of type mqueue. 1155 */ 1156 if (fp->f_type == DTYPE_MQUEUE) 1157 mq_fdclose(td, fd, fp); 1158 FILEDESC_XUNLOCK(fdp); 1159 1160 error = closef(fp, td); 1161 if (holdleaders) { 1162 FILEDESC_XLOCK(fdp); 1163 fdp->fd_holdleaderscount--; 1164 if (fdp->fd_holdleaderscount == 0 && 1165 fdp->fd_holdleaderswakeup != 0) { 1166 fdp->fd_holdleaderswakeup = 0; 1167 wakeup(&fdp->fd_holdleaderscount); 1168 } 1169 FILEDESC_XUNLOCK(fdp); 1170 } 1171 return (error); 1172} 1173 1174/* 1175 * Close a file descriptor. 1176 */ 1177#ifndef _SYS_SYSPROTO_H_ 1178struct close_args { 1179 int fd; 1180}; 1181#endif 1182/* ARGSUSED */ 1183int 1184sys_close(td, uap) 1185 struct thread *td; 1186 struct close_args *uap; 1187{ 1188 1189 return (kern_close(td, uap->fd)); 1190} 1191 1192int 1193kern_close(td, fd) 1194 struct thread *td; 1195 int fd; 1196{ 1197 struct filedesc *fdp; 1198 struct file *fp; 1199 1200 fdp = td->td_proc->p_fd; 1201 1202 AUDIT_SYSCLOSE(td, fd); 1203 1204 FILEDESC_XLOCK(fdp); 1205 if ((fp = fget_locked(fdp, fd)) == NULL) { 1206 FILEDESC_XUNLOCK(fdp); 1207 return (EBADF); 1208 } 1209 fdfree(fdp, fd); 1210 1211 /* closefp() drops the FILEDESC lock for us. */ 1212 return (closefp(fdp, fd, fp, td, 1)); 1213} 1214 1215/* 1216 * Close open file descriptors. 1217 */ 1218#ifndef _SYS_SYSPROTO_H_ 1219struct closefrom_args { 1220 int lowfd; 1221}; 1222#endif 1223/* ARGSUSED */ 1224int 1225sys_closefrom(struct thread *td, struct closefrom_args *uap) 1226{ 1227 struct filedesc *fdp; 1228 int fd; 1229 1230 fdp = td->td_proc->p_fd; 1231 AUDIT_ARG_FD(uap->lowfd); 1232 1233 /* 1234 * Treat negative starting file descriptor values identical to 1235 * closefrom(0) which closes all files. 1236 */ 1237 if (uap->lowfd < 0) 1238 uap->lowfd = 0; 1239 FILEDESC_SLOCK(fdp); 1240 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) { 1241 if (fdp->fd_ofiles[fd].fde_file != NULL) { 1242 FILEDESC_SUNLOCK(fdp); 1243 (void)kern_close(td, fd); 1244 FILEDESC_SLOCK(fdp); 1245 } 1246 } 1247 FILEDESC_SUNLOCK(fdp); 1248 return (0); 1249} 1250 1251#if defined(COMPAT_43) 1252/* 1253 * Return status information about a file descriptor. 1254 */ 1255#ifndef _SYS_SYSPROTO_H_ 1256struct ofstat_args { 1257 int fd; 1258 struct ostat *sb; 1259}; 1260#endif 1261/* ARGSUSED */ 1262int 1263ofstat(struct thread *td, struct ofstat_args *uap) 1264{ 1265 struct ostat oub; 1266 struct stat ub; 1267 int error; 1268 1269 error = kern_fstat(td, uap->fd, &ub); 1270 if (error == 0) { 1271 cvtstat(&ub, &oub); 1272 error = copyout(&oub, uap->sb, sizeof(oub)); 1273 } 1274 return (error); 1275} 1276#endif /* COMPAT_43 */ 1277 1278/* 1279 * Return status information about a file descriptor. 1280 */ 1281#ifndef _SYS_SYSPROTO_H_ 1282struct fstat_args { 1283 int fd; 1284 struct stat *sb; 1285}; 1286#endif 1287/* ARGSUSED */ 1288int 1289sys_fstat(struct thread *td, struct fstat_args *uap) 1290{ 1291 struct stat ub; 1292 int error; 1293 1294 error = kern_fstat(td, uap->fd, &ub); 1295 if (error == 0) 1296 error = copyout(&ub, uap->sb, sizeof(ub)); 1297 return (error); 1298} 1299 1300int 1301kern_fstat(struct thread *td, int fd, struct stat *sbp) 1302{ 1303 struct file *fp; 1304 cap_rights_t rights; 1305 int error; 1306 1307 AUDIT_ARG_FD(fd); 1308 1309 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp); 1310 if (error != 0) 1311 return (error); 1312 1313 AUDIT_ARG_FILE(td->td_proc, fp); 1314 1315 error = fo_stat(fp, sbp, td->td_ucred, td); 1316 fdrop(fp, td); 1317#ifdef KTRACE 1318 if (error == 0 && KTRPOINT(td, KTR_STRUCT)) 1319 ktrstat(sbp); 1320#endif 1321 return (error); 1322} 1323 1324/* 1325 * Return status information about a file descriptor. 1326 */ 1327#ifndef _SYS_SYSPROTO_H_ 1328struct nfstat_args { 1329 int fd; 1330 struct nstat *sb; 1331}; 1332#endif 1333/* ARGSUSED */ 1334int 1335sys_nfstat(struct thread *td, struct nfstat_args *uap) 1336{ 1337 struct nstat nub; 1338 struct stat ub; 1339 int error; 1340 1341 error = kern_fstat(td, uap->fd, &ub); 1342 if (error == 0) { 1343 cvtnstat(&ub, &nub); 1344 error = copyout(&nub, uap->sb, sizeof(nub)); 1345 } 1346 return (error); 1347} 1348 1349/* 1350 * Return pathconf information about a file descriptor. 1351 */ 1352#ifndef _SYS_SYSPROTO_H_ 1353struct fpathconf_args { 1354 int fd; 1355 int name; 1356}; 1357#endif 1358/* ARGSUSED */ 1359int 1360sys_fpathconf(struct thread *td, struct fpathconf_args *uap) 1361{ 1362 struct file *fp; 1363 struct vnode *vp; 1364 cap_rights_t rights; 1365 int error; 1366 1367 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp); 1368 if (error != 0) 1369 return (error); 1370 1371 /* If asynchronous I/O is available, it works for all descriptors. */ 1372 if (uap->name == _PC_ASYNC_IO) { 1373 td->td_retval[0] = async_io_version; 1374 goto out; 1375 } 1376 vp = fp->f_vnode; 1377 if (vp != NULL) { 1378 vn_lock(vp, LK_SHARED | LK_RETRY); 1379 error = VOP_PATHCONF(vp, uap->name, td->td_retval); 1380 VOP_UNLOCK(vp, 0); 1381 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { 1382 if (uap->name != _PC_PIPE_BUF) { 1383 error = EINVAL; 1384 } else { 1385 td->td_retval[0] = PIPE_BUF; 1386 error = 0; 1387 } 1388 } else { 1389 error = EOPNOTSUPP; 1390 } 1391out: 1392 fdrop(fp, td); 1393 return (error); 1394} 1395 1396/* 1397 * Initialize filecaps structure. 1398 */ 1399void 1400filecaps_init(struct filecaps *fcaps) 1401{ 1402 1403 bzero(fcaps, sizeof(*fcaps)); 1404 fcaps->fc_nioctls = -1; 1405} 1406 1407/* 1408 * Copy filecaps structure allocating memory for ioctls array if needed. 1409 */ 1410void 1411filecaps_copy(const struct filecaps *src, struct filecaps *dst) 1412{ 1413 size_t size; 1414 1415 *dst = *src; 1416 if (src->fc_ioctls != NULL) { 1417 KASSERT(src->fc_nioctls > 0, 1418 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls)); 1419 1420 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls; 1421 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK); 1422 bcopy(src->fc_ioctls, dst->fc_ioctls, size); 1423 } 1424} 1425 1426/* 1427 * Move filecaps structure to the new place and clear the old place. 1428 */ 1429void 1430filecaps_move(struct filecaps *src, struct filecaps *dst) 1431{ 1432 1433 *dst = *src; 1434 bzero(src, sizeof(*src)); 1435} 1436 1437/* 1438 * Fill the given filecaps structure with full rights. 1439 */ 1440static void 1441filecaps_fill(struct filecaps *fcaps) 1442{ 1443 1444 CAP_ALL(&fcaps->fc_rights); 1445 fcaps->fc_ioctls = NULL; 1446 fcaps->fc_nioctls = -1; 1447 fcaps->fc_fcntls = CAP_FCNTL_ALL; 1448} 1449 1450/* 1451 * Free memory allocated within filecaps structure. 1452 */ 1453void 1454filecaps_free(struct filecaps *fcaps) 1455{ 1456 1457 free(fcaps->fc_ioctls, M_FILECAPS); 1458 bzero(fcaps, sizeof(*fcaps)); 1459} 1460 1461/* 1462 * Validate the given filecaps structure. 1463 */ 1464static void 1465filecaps_validate(const struct filecaps *fcaps, const char *func) 1466{ 1467 1468 KASSERT(cap_rights_is_valid(&fcaps->fc_rights), 1469 ("%s: invalid rights", func)); 1470 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0, 1471 ("%s: invalid fcntls", func)); 1472 KASSERT(fcaps->fc_fcntls == 0 || 1473 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL), 1474 ("%s: fcntls without CAP_FCNTL", func)); 1475 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 : 1476 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0), 1477 ("%s: invalid ioctls", func)); 1478 KASSERT(fcaps->fc_nioctls == 0 || 1479 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL), 1480 ("%s: ioctls without CAP_IOCTL", func)); 1481} 1482 1483static void 1484fdgrowtable_exp(struct filedesc *fdp, int nfd) 1485{ 1486 int nfd1; 1487 1488 FILEDESC_XLOCK_ASSERT(fdp); 1489 1490 nfd1 = fdp->fd_nfiles * 2; 1491 if (nfd1 < nfd) 1492 nfd1 = nfd; 1493 fdgrowtable(fdp, nfd1); 1494} 1495 1496/* 1497 * Grow the file table to accomodate (at least) nfd descriptors. 1498 */ 1499static void 1500fdgrowtable(struct filedesc *fdp, int nfd) 1501{ 1502 struct filedesc0 *fdp0; 1503 struct freetable *ft; 1504 struct filedescent *ntable; 1505 struct filedescent *otable; 1506 int nnfiles, onfiles; 1507 NDSLOTTYPE *nmap, *omap; 1508 1509 FILEDESC_XLOCK_ASSERT(fdp); 1510 1511 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table")); 1512 1513 /* save old values */ 1514 onfiles = fdp->fd_nfiles; 1515 otable = fdp->fd_ofiles; 1516 omap = fdp->fd_map; 1517 1518 /* compute the size of the new table */ 1519 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ 1520 if (nnfiles <= onfiles) 1521 /* the table is already large enough */ 1522 return; 1523 1524 /* 1525 * Allocate a new table and map. We need enough space for the 1526 * file entries themselves and the struct freetable we will use 1527 * when we decommission the table and place it on the freelist. 1528 * We place the struct freetable in the middle so we don't have 1529 * to worry about padding. 1530 */ 1531 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable), 1532 M_FILEDESC, M_ZERO | M_WAITOK); 1533 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC, 1534 M_ZERO | M_WAITOK); 1535 1536 /* copy the old data over and point at the new tables */ 1537 memcpy(ntable, otable, onfiles * sizeof(*otable)); 1538 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap)); 1539 1540 /* update the pointers and counters */ 1541 fdp->fd_ofiles = ntable; 1542 fdp->fd_map = nmap; 1543 1544 /* 1545 * In order to have a valid pattern for fget_unlocked() 1546 * fdp->fd_nfiles must be the last member to be updated, otherwise 1547 * fget_unlocked() consumers may reference a new, higher value for 1548 * fdp->fd_nfiles before to access the fdp->fd_ofiles array, 1549 * resulting in OOB accesses. 1550 */ 1551 atomic_store_rel_int(&fdp->fd_nfiles, nnfiles); 1552 1553 /* 1554 * Do not free the old file table, as some threads may still 1555 * reference entries within it. Instead, place it on a freelist 1556 * which will be processed when the struct filedesc is released. 1557 * 1558 * Do, however, free the old map. 1559 * 1560 * Note that if onfiles == NDFILE, we're dealing with the original 1561 * static allocation contained within (struct filedesc0 *)fdp, 1562 * which must not be freed. 1563 */ 1564 if (onfiles > NDFILE) { 1565 ft = (struct freetable *)&otable[onfiles]; 1566 fdp0 = (struct filedesc0 *)fdp; 1567 ft->ft_table = otable; 1568 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next); 1569 free(omap, M_FILEDESC); 1570 } 1571} 1572 1573/* 1574 * Allocate a file descriptor for the process. 1575 */ 1576int 1577fdalloc(struct thread *td, int minfd, int *result) 1578{ 1579 struct proc *p = td->td_proc; 1580 struct filedesc *fdp = p->p_fd; 1581 int fd = -1, maxfd, allocfd; 1582#ifdef RACCT 1583 int error; 1584#endif 1585 1586 FILEDESC_XLOCK_ASSERT(fdp); 1587 1588 if (fdp->fd_freefile > minfd) 1589 minfd = fdp->fd_freefile; 1590 1591 maxfd = getmaxfd(p); 1592 1593 /* 1594 * Search the bitmap for a free descriptor starting at minfd. 1595 * If none is found, grow the file table. 1596 */ 1597 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); 1598 if (fd >= maxfd) 1599 return (EMFILE); 1600 if (fd >= fdp->fd_nfiles) { 1601 allocfd = min(fd * 2, maxfd); 1602#ifdef RACCT 1603 PROC_LOCK(p); 1604 error = racct_set(p, RACCT_NOFILE, allocfd); 1605 PROC_UNLOCK(p); 1606 if (error != 0) 1607 return (EMFILE); 1608#endif 1609 /* 1610 * fd is already equal to first free descriptor >= minfd, so 1611 * we only need to grow the table and we are done. 1612 */ 1613 fdgrowtable_exp(fdp, allocfd); 1614 } 1615 1616 /* 1617 * Perform some sanity checks, then mark the file descriptor as 1618 * used and return it to the caller. 1619 */ 1620 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), 1621 ("invalid descriptor %d", fd)); 1622 KASSERT(!fdisused(fdp, fd), 1623 ("fd_first_free() returned non-free descriptor")); 1624 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL, 1625 ("file descriptor isn't free")); 1626 KASSERT(fdp->fd_ofiles[fd].fde_flags == 0, ("file flags are set")); 1627 fdused(fdp, fd); 1628 *result = fd; 1629 return (0); 1630} 1631 1632/* 1633 * Allocate n file descriptors for the process. 1634 */ 1635int 1636fdallocn(struct thread *td, int minfd, int *fds, int n) 1637{ 1638 struct proc *p = td->td_proc; 1639 struct filedesc *fdp = p->p_fd; 1640 int i; 1641 1642 FILEDESC_XLOCK_ASSERT(fdp); 1643 1644 if (!fdavail(td, n)) 1645 return (EMFILE); 1646 1647 for (i = 0; i < n; i++) 1648 if (fdalloc(td, 0, &fds[i]) != 0) 1649 break; 1650 1651 if (i < n) { 1652 for (i--; i >= 0; i--) 1653 fdunused(fdp, fds[i]); 1654 return (EMFILE); 1655 } 1656 1657 return (0); 1658} 1659 1660/* 1661 * Check to see whether n user file descriptors are available to the process 1662 * p. 1663 */ 1664int 1665fdavail(struct thread *td, int n) 1666{ 1667 struct proc *p = td->td_proc; 1668 struct filedesc *fdp = td->td_proc->p_fd; 1669 int i, lim, last; 1670 1671 FILEDESC_LOCK_ASSERT(fdp); 1672 1673 /* 1674 * XXX: This is only called from uipc_usrreq.c:unp_externalize(); 1675 * call racct_add() from there instead of dealing with containers 1676 * here. 1677 */ 1678 lim = getmaxfd(p); 1679 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) 1680 return (1); 1681 last = min(fdp->fd_nfiles, lim); 1682 for (i = fdp->fd_freefile; i < last; i++) { 1683 if (fdp->fd_ofiles[i].fde_file == NULL && --n <= 0) 1684 return (1); 1685 } 1686 return (0); 1687} 1688 1689/* 1690 * Create a new open file structure and allocate a file decriptor for the 1691 * process that refers to it. We add one reference to the file for the 1692 * descriptor table and one reference for resultfp. This is to prevent us 1693 * being preempted and the entry in the descriptor table closed after we 1694 * release the FILEDESC lock. 1695 */ 1696int 1697falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) 1698{ 1699 struct file *fp; 1700 int error, fd; 1701 1702 error = falloc_noinstall(td, &fp); 1703 if (error) 1704 return (error); /* no reference held on error */ 1705 1706 error = finstall(td, fp, &fd, flags, NULL); 1707 if (error) { 1708 fdrop(fp, td); /* one reference (fp only) */ 1709 return (error); 1710 } 1711 1712 if (resultfp != NULL) 1713 *resultfp = fp; /* copy out result */ 1714 else 1715 fdrop(fp, td); /* release local reference */ 1716 1717 if (resultfd != NULL) 1718 *resultfd = fd; 1719 1720 return (0); 1721} 1722 1723/* 1724 * Create a new open file structure without allocating a file descriptor. 1725 */ 1726int 1727falloc_noinstall(struct thread *td, struct file **resultfp) 1728{ 1729 struct file *fp; 1730 int maxuserfiles = maxfiles - (maxfiles / 20); 1731 static struct timeval lastfail; 1732 static int curfail; 1733 1734 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); 1735 1736 if ((openfiles >= maxuserfiles && 1737 priv_check(td, PRIV_MAXFILES) != 0) || 1738 openfiles >= maxfiles) { 1739 if (ppsratecheck(&lastfail, &curfail, 1)) { 1740 printf("kern.maxfiles limit exceeded by uid %i, " 1741 "please see tuning(7).\n", td->td_ucred->cr_ruid); 1742 } 1743 return (ENFILE); 1744 } 1745 atomic_add_int(&openfiles, 1); 1746 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); 1747 refcount_init(&fp->f_count, 1); 1748 fp->f_cred = crhold(td->td_ucred); 1749 fp->f_ops = &badfileops; 1750 fp->f_data = NULL; 1751 fp->f_vnode = NULL; 1752 *resultfp = fp; 1753 return (0); 1754} 1755 1756/* 1757 * Install a file in a file descriptor table. 1758 */ 1759int 1760finstall(struct thread *td, struct file *fp, int *fd, int flags, 1761 struct filecaps *fcaps) 1762{ 1763 struct filedesc *fdp = td->td_proc->p_fd; 1764 struct filedescent *fde; 1765 int error; 1766 1767 KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); 1768 KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); 1769 if (fcaps != NULL) 1770 filecaps_validate(fcaps, __func__); 1771 1772 FILEDESC_XLOCK(fdp); 1773 if ((error = fdalloc(td, 0, fd))) { 1774 FILEDESC_XUNLOCK(fdp); 1775 return (error); 1776 } 1777 fhold(fp); 1778 fde = &fdp->fd_ofiles[*fd]; 1779 fde->fde_file = fp; 1780 if ((flags & O_CLOEXEC) != 0) 1781 fde->fde_flags |= UF_EXCLOSE; 1782 if (fcaps != NULL) 1783 filecaps_move(fcaps, &fde->fde_caps); 1784 else 1785 filecaps_fill(&fde->fde_caps); 1786 FILEDESC_XUNLOCK(fdp); 1787 return (0); 1788} 1789 1790/* 1791 * Build a new filedesc structure from another. 1792 * Copy the current, root, and jail root vnode references. 1793 */ 1794struct filedesc * 1795fdinit(struct filedesc *fdp) 1796{ 1797 struct filedesc0 *newfdp; 1798 1799 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); 1800 FILEDESC_LOCK_INIT(&newfdp->fd_fd); 1801 if (fdp != NULL) { 1802 FILEDESC_XLOCK(fdp); 1803 newfdp->fd_fd.fd_cdir = fdp->fd_cdir; 1804 if (newfdp->fd_fd.fd_cdir) 1805 VREF(newfdp->fd_fd.fd_cdir); 1806 newfdp->fd_fd.fd_rdir = fdp->fd_rdir; 1807 if (newfdp->fd_fd.fd_rdir) 1808 VREF(newfdp->fd_fd.fd_rdir); 1809 newfdp->fd_fd.fd_jdir = fdp->fd_jdir; 1810 if (newfdp->fd_fd.fd_jdir) 1811 VREF(newfdp->fd_fd.fd_jdir); 1812 FILEDESC_XUNLOCK(fdp); 1813 } 1814 1815 /* Create the file descriptor table. */ 1816 newfdp->fd_fd.fd_refcnt = 1; 1817 newfdp->fd_fd.fd_holdcnt = 1; 1818 newfdp->fd_fd.fd_cmask = CMASK; 1819 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; 1820 newfdp->fd_fd.fd_nfiles = NDFILE; 1821 newfdp->fd_fd.fd_map = newfdp->fd_dmap; 1822 newfdp->fd_fd.fd_lastfile = -1; 1823 return (&newfdp->fd_fd); 1824} 1825 1826static struct filedesc * 1827fdhold(struct proc *p) 1828{ 1829 struct filedesc *fdp; 1830 1831 mtx_lock(&fdesc_mtx); 1832 fdp = p->p_fd; 1833 if (fdp != NULL) 1834 fdp->fd_holdcnt++; 1835 mtx_unlock(&fdesc_mtx); 1836 return (fdp); 1837} 1838 1839static void 1840fddrop(struct filedesc *fdp) 1841{ 1842 struct filedesc0 *fdp0; 1843 struct freetable *ft; 1844 int i; 1845 1846 mtx_lock(&fdesc_mtx); 1847 i = --fdp->fd_holdcnt; 1848 mtx_unlock(&fdesc_mtx); 1849 if (i > 0) 1850 return; 1851 1852 FILEDESC_LOCK_DESTROY(fdp); 1853 fdp0 = (struct filedesc0 *)fdp; 1854 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { 1855 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); 1856 free(ft->ft_table, M_FILEDESC); 1857 } 1858 free(fdp, M_FILEDESC); 1859} 1860 1861/* 1862 * Share a filedesc structure. 1863 */ 1864struct filedesc * 1865fdshare(struct filedesc *fdp) 1866{ 1867 1868 FILEDESC_XLOCK(fdp); 1869 fdp->fd_refcnt++; 1870 FILEDESC_XUNLOCK(fdp); 1871 return (fdp); 1872} 1873 1874/* 1875 * Unshare a filedesc structure, if necessary by making a copy 1876 */ 1877void 1878fdunshare(struct proc *p, struct thread *td) 1879{ 1880 1881 FILEDESC_XLOCK(p->p_fd); 1882 if (p->p_fd->fd_refcnt > 1) { 1883 struct filedesc *tmp; 1884 1885 FILEDESC_XUNLOCK(p->p_fd); 1886 tmp = fdcopy(p->p_fd); 1887 fdescfree(td); 1888 p->p_fd = tmp; 1889 } else 1890 FILEDESC_XUNLOCK(p->p_fd); 1891} 1892 1893/* 1894 * Copy a filedesc structure. A NULL pointer in returns a NULL reference, 1895 * this is to ease callers, not catch errors. 1896 */ 1897struct filedesc * 1898fdcopy(struct filedesc *fdp) 1899{ 1900 struct filedesc *newfdp; 1901 struct filedescent *nfde, *ofde; 1902 int i; 1903 1904 /* Certain daemons might not have file descriptors. */ 1905 if (fdp == NULL) 1906 return (NULL); 1907 1908 newfdp = fdinit(fdp); 1909 FILEDESC_SLOCK(fdp); 1910 while (fdp->fd_lastfile >= newfdp->fd_nfiles) { 1911 FILEDESC_SUNLOCK(fdp); 1912 FILEDESC_XLOCK(newfdp); 1913 fdgrowtable(newfdp, fdp->fd_lastfile + 1); 1914 FILEDESC_XUNLOCK(newfdp); 1915 FILEDESC_SLOCK(fdp); 1916 } 1917 /* copy all passable descriptors (i.e. not kqueue) */ 1918 newfdp->fd_freefile = -1; 1919 for (i = 0; i <= fdp->fd_lastfile; ++i) { 1920 ofde = &fdp->fd_ofiles[i]; 1921 if (fdisused(fdp, i) && 1922 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) && 1923 ofde->fde_file->f_ops != &badfileops) { 1924 nfde = &newfdp->fd_ofiles[i]; 1925 *nfde = *ofde; 1926 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps); 1927 fhold(nfde->fde_file); 1928 newfdp->fd_lastfile = i; 1929 } else { 1930 if (newfdp->fd_freefile == -1) 1931 newfdp->fd_freefile = i; 1932 } 1933 } 1934 newfdp->fd_cmask = fdp->fd_cmask; 1935 FILEDESC_SUNLOCK(fdp); 1936 FILEDESC_XLOCK(newfdp); 1937 for (i = 0; i <= newfdp->fd_lastfile; ++i) { 1938 if (newfdp->fd_ofiles[i].fde_file != NULL) 1939 fdused(newfdp, i); 1940 } 1941 if (newfdp->fd_freefile == -1) 1942 newfdp->fd_freefile = i; 1943 FILEDESC_XUNLOCK(newfdp); 1944 return (newfdp); 1945} 1946 1947/* 1948 * Release a filedesc structure. 1949 */ 1950void 1951fdescfree(struct thread *td) 1952{ 1953 struct filedesc *fdp; 1954 int i; 1955 struct filedesc_to_leader *fdtol; 1956 struct file *fp; 1957 struct vnode *cdir, *jdir, *rdir, *vp; 1958 struct flock lf; 1959 1960 /* Certain daemons might not have file descriptors. */ 1961 fdp = td->td_proc->p_fd; 1962 if (fdp == NULL) 1963 return; 1964 1965#ifdef RACCT 1966 PROC_LOCK(td->td_proc); 1967 racct_set(td->td_proc, RACCT_NOFILE, 0); 1968 PROC_UNLOCK(td->td_proc); 1969#endif 1970 1971 /* Check for special need to clear POSIX style locks */ 1972 fdtol = td->td_proc->p_fdtol; 1973 if (fdtol != NULL) { 1974 FILEDESC_XLOCK(fdp); 1975 KASSERT(fdtol->fdl_refcount > 0, 1976 ("filedesc_to_refcount botch: fdl_refcount=%d", 1977 fdtol->fdl_refcount)); 1978 if (fdtol->fdl_refcount == 1 && 1979 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 1980 for (i = 0; i <= fdp->fd_lastfile; i++) { 1981 fp = fdp->fd_ofiles[i].fde_file; 1982 if (fp == NULL || fp->f_type != DTYPE_VNODE) 1983 continue; 1984 fhold(fp); 1985 FILEDESC_XUNLOCK(fdp); 1986 lf.l_whence = SEEK_SET; 1987 lf.l_start = 0; 1988 lf.l_len = 0; 1989 lf.l_type = F_UNLCK; 1990 vp = fp->f_vnode; 1991 (void) VOP_ADVLOCK(vp, 1992 (caddr_t)td->td_proc->p_leader, F_UNLCK, 1993 &lf, F_POSIX); 1994 FILEDESC_XLOCK(fdp); 1995 fdrop(fp, td); 1996 } 1997 } 1998 retry: 1999 if (fdtol->fdl_refcount == 1) { 2000 if (fdp->fd_holdleaderscount > 0 && 2001 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2002 /* 2003 * close() or do_dup() has cleared a reference 2004 * in a shared file descriptor table. 2005 */ 2006 fdp->fd_holdleaderswakeup = 1; 2007 sx_sleep(&fdp->fd_holdleaderscount, 2008 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); 2009 goto retry; 2010 } 2011 if (fdtol->fdl_holdcount > 0) { 2012 /* 2013 * Ensure that fdtol->fdl_leader remains 2014 * valid in closef(). 2015 */ 2016 fdtol->fdl_wakeup = 1; 2017 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, 2018 "fdlhold", 0); 2019 goto retry; 2020 } 2021 } 2022 fdtol->fdl_refcount--; 2023 if (fdtol->fdl_refcount == 0 && 2024 fdtol->fdl_holdcount == 0) { 2025 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; 2026 fdtol->fdl_prev->fdl_next = fdtol->fdl_next; 2027 } else 2028 fdtol = NULL; 2029 td->td_proc->p_fdtol = NULL; 2030 FILEDESC_XUNLOCK(fdp); 2031 if (fdtol != NULL) 2032 free(fdtol, M_FILEDESC_TO_LEADER); 2033 } 2034 FILEDESC_XLOCK(fdp); 2035 i = --fdp->fd_refcnt; 2036 FILEDESC_XUNLOCK(fdp); 2037 if (i > 0) 2038 return; 2039 2040 for (i = 0; i <= fdp->fd_lastfile; i++) { 2041 fp = fdp->fd_ofiles[i].fde_file; 2042 if (fp != NULL) { 2043 FILEDESC_XLOCK(fdp); 2044 fdfree(fdp, i); 2045 FILEDESC_XUNLOCK(fdp); 2046 (void) closef(fp, td); 2047 } 2048 } 2049 FILEDESC_XLOCK(fdp); 2050 2051 /* XXX This should happen earlier. */ 2052 mtx_lock(&fdesc_mtx); 2053 td->td_proc->p_fd = NULL; 2054 mtx_unlock(&fdesc_mtx); 2055 2056 if (fdp->fd_nfiles > NDFILE) 2057 free(fdp->fd_ofiles, M_FILEDESC); 2058 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) 2059 free(fdp->fd_map, M_FILEDESC); 2060 2061 fdp->fd_nfiles = 0; 2062 2063 cdir = fdp->fd_cdir; 2064 fdp->fd_cdir = NULL; 2065 rdir = fdp->fd_rdir; 2066 fdp->fd_rdir = NULL; 2067 jdir = fdp->fd_jdir; 2068 fdp->fd_jdir = NULL; 2069 FILEDESC_XUNLOCK(fdp); 2070 2071 if (cdir != NULL) 2072 vrele(cdir); 2073 if (rdir != NULL) 2074 vrele(rdir); 2075 if (jdir != NULL) 2076 vrele(jdir); 2077 2078 fddrop(fdp); 2079} 2080 2081/* 2082 * For setugid programs, we don't want to people to use that setugidness 2083 * to generate error messages which write to a file which otherwise would 2084 * otherwise be off-limits to the process. We check for filesystems where 2085 * the vnode can change out from under us after execve (like [lin]procfs). 2086 * 2087 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is 2088 * sufficient. We also don't check for setugidness since we know we are. 2089 */ 2090static int 2091is_unsafe(struct file *fp) 2092{ 2093 if (fp->f_type == DTYPE_VNODE) { 2094 struct vnode *vp = fp->f_vnode; 2095 2096 if ((vp->v_vflag & VV_PROCDEP) != 0) 2097 return (1); 2098 } 2099 return (0); 2100} 2101 2102/* 2103 * Make this setguid thing safe, if at all possible. 2104 */ 2105void 2106setugidsafety(struct thread *td) 2107{ 2108 struct filedesc *fdp; 2109 struct file *fp; 2110 int i; 2111 2112 /* Certain daemons might not have file descriptors. */ 2113 fdp = td->td_proc->p_fd; 2114 if (fdp == NULL) 2115 return; 2116 2117 /* 2118 * Note: fdp->fd_ofiles may be reallocated out from under us while 2119 * we are blocked in a close. Be careful! 2120 */ 2121 FILEDESC_XLOCK(fdp); 2122 for (i = 0; i <= fdp->fd_lastfile; i++) { 2123 if (i > 2) 2124 break; 2125 fp = fdp->fd_ofiles[i].fde_file; 2126 if (fp != NULL && is_unsafe(fp)) { 2127 knote_fdclose(td, i); 2128 /* 2129 * NULL-out descriptor prior to close to avoid 2130 * a race while close blocks. 2131 */ 2132 fdfree(fdp, i); 2133 FILEDESC_XUNLOCK(fdp); 2134 (void) closef(fp, td); 2135 FILEDESC_XLOCK(fdp); 2136 } 2137 } 2138 FILEDESC_XUNLOCK(fdp); 2139} 2140 2141/* 2142 * If a specific file object occupies a specific file descriptor, close the 2143 * file descriptor entry and drop a reference on the file object. This is a 2144 * convenience function to handle a subsequent error in a function that calls 2145 * falloc() that handles the race that another thread might have closed the 2146 * file descriptor out from under the thread creating the file object. 2147 */ 2148void 2149fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) 2150{ 2151 2152 FILEDESC_XLOCK(fdp); 2153 if (fdp->fd_ofiles[idx].fde_file == fp) { 2154 fdfree(fdp, idx); 2155 FILEDESC_XUNLOCK(fdp); 2156 fdrop(fp, td); 2157 } else 2158 FILEDESC_XUNLOCK(fdp); 2159} 2160 2161/* 2162 * Close any files on exec? 2163 */ 2164void 2165fdcloseexec(struct thread *td) 2166{ 2167 struct filedesc *fdp; 2168 struct filedescent *fde; 2169 struct file *fp; 2170 int i; 2171 2172 /* Certain daemons might not have file descriptors. */ 2173 fdp = td->td_proc->p_fd; 2174 if (fdp == NULL) 2175 return; 2176 2177 /* 2178 * We cannot cache fd_ofiles since operations 2179 * may block and rip them out from under us. 2180 */ 2181 FILEDESC_XLOCK(fdp); 2182 for (i = 0; i <= fdp->fd_lastfile; i++) { 2183 fde = &fdp->fd_ofiles[i]; 2184 fp = fde->fde_file; 2185 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || 2186 (fde->fde_flags & UF_EXCLOSE))) { 2187 fdfree(fdp, i); 2188 (void) closefp(fdp, i, fp, td, 0); 2189 /* closefp() drops the FILEDESC lock. */ 2190 FILEDESC_XLOCK(fdp); 2191 } 2192 } 2193 FILEDESC_XUNLOCK(fdp); 2194} 2195 2196/* 2197 * It is unsafe for set[ug]id processes to be started with file 2198 * descriptors 0..2 closed, as these descriptors are given implicit 2199 * significance in the Standard C library. fdcheckstd() will create a 2200 * descriptor referencing /dev/null for each of stdin, stdout, and 2201 * stderr that is not already open. 2202 */ 2203int 2204fdcheckstd(struct thread *td) 2205{ 2206 struct filedesc *fdp; 2207 register_t retval, save; 2208 int i, error, devnull; 2209 2210 fdp = td->td_proc->p_fd; 2211 if (fdp == NULL) 2212 return (0); 2213 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); 2214 devnull = -1; 2215 error = 0; 2216 for (i = 0; i < 3; i++) { 2217 if (fdp->fd_ofiles[i].fde_file != NULL) 2218 continue; 2219 if (devnull < 0) { 2220 save = td->td_retval[0]; 2221 error = kern_open(td, "/dev/null", UIO_SYSSPACE, 2222 O_RDWR, 0); 2223 devnull = td->td_retval[0]; 2224 td->td_retval[0] = save; 2225 if (error) 2226 break; 2227 KASSERT(devnull == i, ("oof, we didn't get our fd")); 2228 } else { 2229 error = do_dup(td, DUP_FIXED, devnull, i, &retval); 2230 if (error != 0) 2231 break; 2232 } 2233 } 2234 return (error); 2235} 2236 2237/* 2238 * Internal form of close. Decrement reference count on file structure. 2239 * Note: td may be NULL when closing a file that was being passed in a 2240 * message. 2241 * 2242 * XXXRW: Giant is not required for the caller, but often will be held; this 2243 * makes it moderately likely the Giant will be recursed in the VFS case. 2244 */ 2245int 2246closef(struct file *fp, struct thread *td) 2247{ 2248 struct vnode *vp; 2249 struct flock lf; 2250 struct filedesc_to_leader *fdtol; 2251 struct filedesc *fdp; 2252 2253 /* 2254 * POSIX record locking dictates that any close releases ALL 2255 * locks owned by this process. This is handled by setting 2256 * a flag in the unlock to free ONLY locks obeying POSIX 2257 * semantics, and not to free BSD-style file locks. 2258 * If the descriptor was in a message, POSIX-style locks 2259 * aren't passed with the descriptor, and the thread pointer 2260 * will be NULL. Callers should be careful only to pass a 2261 * NULL thread pointer when there really is no owning 2262 * context that might have locks, or the locks will be 2263 * leaked. 2264 */ 2265 if (fp->f_type == DTYPE_VNODE && td != NULL) { 2266 vp = fp->f_vnode; 2267 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { 2268 lf.l_whence = SEEK_SET; 2269 lf.l_start = 0; 2270 lf.l_len = 0; 2271 lf.l_type = F_UNLCK; 2272 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, 2273 F_UNLCK, &lf, F_POSIX); 2274 } 2275 fdtol = td->td_proc->p_fdtol; 2276 if (fdtol != NULL) { 2277 /* 2278 * Handle special case where file descriptor table is 2279 * shared between multiple process leaders. 2280 */ 2281 fdp = td->td_proc->p_fd; 2282 FILEDESC_XLOCK(fdp); 2283 for (fdtol = fdtol->fdl_next; 2284 fdtol != td->td_proc->p_fdtol; 2285 fdtol = fdtol->fdl_next) { 2286 if ((fdtol->fdl_leader->p_flag & 2287 P_ADVLOCK) == 0) 2288 continue; 2289 fdtol->fdl_holdcount++; 2290 FILEDESC_XUNLOCK(fdp); 2291 lf.l_whence = SEEK_SET; 2292 lf.l_start = 0; 2293 lf.l_len = 0; 2294 lf.l_type = F_UNLCK; 2295 vp = fp->f_vnode; 2296 (void) VOP_ADVLOCK(vp, 2297 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, 2298 F_POSIX); 2299 FILEDESC_XLOCK(fdp); 2300 fdtol->fdl_holdcount--; 2301 if (fdtol->fdl_holdcount == 0 && 2302 fdtol->fdl_wakeup != 0) { 2303 fdtol->fdl_wakeup = 0; 2304 wakeup(fdtol); 2305 } 2306 } 2307 FILEDESC_XUNLOCK(fdp); 2308 } 2309 } 2310 return (fdrop(fp, td)); 2311} 2312 2313/* 2314 * Initialize the file pointer with the specified properties. 2315 * 2316 * The ops are set with release semantics to be certain that the flags, type, 2317 * and data are visible when ops is. This is to prevent ops methods from being 2318 * called with bad data. 2319 */ 2320void 2321finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) 2322{ 2323 fp->f_data = data; 2324 fp->f_flag = flag; 2325 fp->f_type = type; 2326 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); 2327} 2328 2329int 2330fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 2331 int needfcntl, struct file **fpp, cap_rights_t *haverightsp) 2332{ 2333 struct file *fp; 2334 u_int count; 2335#ifdef CAPABILITIES 2336 cap_rights_t haverights; 2337 int error; 2338#endif 2339 2340 /* 2341 * Avoid reads reordering and then a first access to the 2342 * fdp->fd_ofiles table which could result in OOB operation. 2343 */ 2344 if (fd < 0 || fd >= atomic_load_acq_int(&fdp->fd_nfiles)) 2345 return (EBADF); 2346 /* 2347 * Fetch the descriptor locklessly. We avoid fdrop() races by 2348 * never raising a refcount above 0. To accomplish this we have 2349 * to use a cmpset loop rather than an atomic_add. The descriptor 2350 * must be re-verified once we acquire a reference to be certain 2351 * that the identity is still correct and we did not lose a race 2352 * due to preemption. 2353 */ 2354 for (;;) { 2355 fp = fdp->fd_ofiles[fd].fde_file; 2356 if (fp == NULL) 2357 return (EBADF); 2358#ifdef CAPABILITIES 2359 haverights = *cap_rights(fdp, fd); 2360 if (needrightsp != NULL) { 2361 error = cap_check(&haverights, needrightsp); 2362 if (error != 0) 2363 return (error); 2364 if (cap_rights_is_set(needrightsp, CAP_FCNTL)) { 2365 error = cap_fcntl_check(fdp, fd, needfcntl); 2366 if (error != 0) 2367 return (error); 2368 } 2369 } 2370#endif 2371 count = fp->f_count; 2372 if (count == 0) 2373 continue; 2374 /* 2375 * Use an acquire barrier to prevent caching of fd_ofiles 2376 * so it is refreshed for verification. 2377 */ 2378 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) 2379 continue; 2380 if (fp == fdp->fd_ofiles[fd].fde_file) 2381 break; 2382 fdrop(fp, curthread); 2383 } 2384 *fpp = fp; 2385 if (haverightsp != NULL) { 2386#ifdef CAPABILITIES 2387 *haverightsp = haverights; 2388#else 2389 CAP_ALL(haverightsp); 2390#endif 2391 } 2392 return (0); 2393} 2394 2395/* 2396 * Extract the file pointer associated with the specified descriptor for the 2397 * current user process. 2398 * 2399 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is 2400 * returned. 2401 * 2402 * File's rights will be checked against the capability rights mask. 2403 * 2404 * If an error occured the non-zero error is returned and *fpp is set to 2405 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is 2406 * responsible for fdrop(). 2407 */ 2408static __inline int 2409_fget(struct thread *td, int fd, struct file **fpp, int flags, 2410 cap_rights_t *needrightsp, u_char *maxprotp) 2411{ 2412 struct filedesc *fdp; 2413 struct file *fp; 2414 cap_rights_t haverights, needrights; 2415 int error; 2416 2417 *fpp = NULL; 2418 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2419 return (EBADF); 2420 if (needrightsp != NULL) 2421 needrights = *needrightsp; 2422 else 2423 cap_rights_init(&needrights); 2424 if (maxprotp != NULL) 2425 cap_rights_set(&needrights, CAP_MMAP); 2426 error = fget_unlocked(fdp, fd, &needrights, 0, &fp, &haverights); 2427 if (error != 0) 2428 return (error); 2429 if (fp->f_ops == &badfileops) { 2430 fdrop(fp, td); 2431 return (EBADF); 2432 } 2433 2434#ifdef CAPABILITIES 2435 /* 2436 * If requested, convert capability rights to access flags. 2437 */ 2438 if (maxprotp != NULL) 2439 *maxprotp = cap_rights_to_vmprot(&haverights); 2440#else /* !CAPABILITIES */ 2441 if (maxprotp != NULL) 2442 *maxprotp = VM_PROT_ALL; 2443#endif /* CAPABILITIES */ 2444 2445 /* 2446 * FREAD and FWRITE failure return EBADF as per POSIX. 2447 */ 2448 error = 0; 2449 switch (flags) { 2450 case FREAD: 2451 case FWRITE: 2452 if ((fp->f_flag & flags) == 0) 2453 error = EBADF; 2454 break; 2455 case FEXEC: 2456 if ((fp->f_flag & (FREAD | FEXEC)) == 0 || 2457 ((fp->f_flag & FWRITE) != 0)) 2458 error = EBADF; 2459 break; 2460 case 0: 2461 break; 2462 default: 2463 KASSERT(0, ("wrong flags")); 2464 } 2465 2466 if (error != 0) { 2467 fdrop(fp, td); 2468 return (error); 2469 } 2470 2471 *fpp = fp; 2472 return (0); 2473} 2474 2475int 2476fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2477{ 2478 2479 return(_fget(td, fd, fpp, 0, rightsp, NULL)); 2480} 2481 2482int 2483fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp, 2484 struct file **fpp) 2485{ 2486 2487 return (_fget(td, fd, fpp, 0, rightsp, maxprotp)); 2488} 2489 2490int 2491fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2492{ 2493 2494 return(_fget(td, fd, fpp, FREAD, rightsp, NULL)); 2495} 2496 2497int 2498fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp) 2499{ 2500 2501 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL)); 2502} 2503 2504/* 2505 * Like fget() but loads the underlying vnode, or returns an error if the 2506 * descriptor does not represent a vnode. Note that pipes use vnodes but 2507 * never have VM objects. The returned vnode will be vref()'d. 2508 * 2509 * XXX: what about the unused flags ? 2510 */ 2511static __inline int 2512_fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp, 2513 struct vnode **vpp) 2514{ 2515 struct file *fp; 2516 int error; 2517 2518 *vpp = NULL; 2519 error = _fget(td, fd, &fp, flags, needrightsp, NULL); 2520 if (error != 0) 2521 return (error); 2522 if (fp->f_vnode == NULL) { 2523 error = EINVAL; 2524 } else { 2525 *vpp = fp->f_vnode; 2526 vref(*vpp); 2527 } 2528 fdrop(fp, td); 2529 2530 return (error); 2531} 2532 2533int 2534fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2535{ 2536 2537 return (_fgetvp(td, fd, 0, rightsp, vpp)); 2538} 2539 2540int 2541fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp, 2542 struct filecaps *havecaps, struct vnode **vpp) 2543{ 2544 struct filedesc *fdp; 2545 struct file *fp; 2546#ifdef CAPABILITIES 2547 int error; 2548#endif 2549 2550 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) 2551 return (EBADF); 2552 2553 fp = fget_locked(fdp, fd); 2554 if (fp == NULL || fp->f_ops == &badfileops) 2555 return (EBADF); 2556 2557#ifdef CAPABILITIES 2558 if (needrightsp != NULL) { 2559 error = cap_check(cap_rights(fdp, fd), needrightsp); 2560 if (error != 0) 2561 return (error); 2562 } 2563#endif 2564 2565 if (fp->f_vnode == NULL) 2566 return (EINVAL); 2567 2568 *vpp = fp->f_vnode; 2569 vref(*vpp); 2570 filecaps_copy(&fdp->fd_ofiles[fd].fde_caps, havecaps); 2571 2572 return (0); 2573} 2574 2575int 2576fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2577{ 2578 2579 return (_fgetvp(td, fd, FREAD, rightsp, vpp)); 2580} 2581 2582int 2583fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp) 2584{ 2585 2586 return (_fgetvp(td, fd, FEXEC, rightsp, vpp)); 2587} 2588 2589#ifdef notyet 2590int 2591fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp, 2592 struct vnode **vpp) 2593{ 2594 2595 return (_fgetvp(td, fd, FWRITE, rightsp, vpp)); 2596} 2597#endif 2598 2599/* 2600 * Like fget() but loads the underlying socket, or returns an error if the 2601 * descriptor does not represent a socket. 2602 * 2603 * We bump the ref count on the returned socket. XXX Also obtain the SX lock 2604 * in the future. 2605 * 2606 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely 2607 * on their file descriptor reference to prevent the socket from being free'd 2608 * during use. 2609 */ 2610int 2611fgetsock(struct thread *td, int fd, cap_rights_t *rightsp, struct socket **spp, 2612 u_int *fflagp) 2613{ 2614 struct file *fp; 2615 int error; 2616 2617 *spp = NULL; 2618 if (fflagp != NULL) 2619 *fflagp = 0; 2620 if ((error = _fget(td, fd, &fp, 0, rightsp, NULL)) != 0) 2621 return (error); 2622 if (fp->f_type != DTYPE_SOCKET) { 2623 error = ENOTSOCK; 2624 } else { 2625 *spp = fp->f_data; 2626 if (fflagp) 2627 *fflagp = fp->f_flag; 2628 SOCK_LOCK(*spp); 2629 soref(*spp); 2630 SOCK_UNLOCK(*spp); 2631 } 2632 fdrop(fp, td); 2633 2634 return (error); 2635} 2636 2637/* 2638 * Drop the reference count on the socket and XXX release the SX lock in the 2639 * future. The last reference closes the socket. 2640 * 2641 * Note: fputsock() is deprecated, see comment for fgetsock(). 2642 */ 2643void 2644fputsock(struct socket *so) 2645{ 2646 2647 ACCEPT_LOCK(); 2648 SOCK_LOCK(so); 2649 CURVNET_SET(so->so_vnet); 2650 sorele(so); 2651 CURVNET_RESTORE(); 2652} 2653 2654/* 2655 * Handle the last reference to a file being closed. 2656 */ 2657int 2658_fdrop(struct file *fp, struct thread *td) 2659{ 2660 int error; 2661 2662 error = 0; 2663 if (fp->f_count != 0) 2664 panic("fdrop: count %d", fp->f_count); 2665 if (fp->f_ops != &badfileops) 2666 error = fo_close(fp, td); 2667 atomic_subtract_int(&openfiles, 1); 2668 crfree(fp->f_cred); 2669 free(fp->f_advice, M_FADVISE); 2670 uma_zfree(file_zone, fp); 2671 2672 return (error); 2673} 2674 2675/* 2676 * Apply an advisory lock on a file descriptor. 2677 * 2678 * Just attempt to get a record lock of the requested type on the entire file 2679 * (l_whence = SEEK_SET, l_start = 0, l_len = 0). 2680 */ 2681#ifndef _SYS_SYSPROTO_H_ 2682struct flock_args { 2683 int fd; 2684 int how; 2685}; 2686#endif 2687/* ARGSUSED */ 2688int 2689sys_flock(struct thread *td, struct flock_args *uap) 2690{ 2691 struct file *fp; 2692 struct vnode *vp; 2693 struct flock lf; 2694 cap_rights_t rights; 2695 int error; 2696 2697 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp); 2698 if (error != 0) 2699 return (error); 2700 if (fp->f_type != DTYPE_VNODE) { 2701 fdrop(fp, td); 2702 return (EOPNOTSUPP); 2703 } 2704 2705 vp = fp->f_vnode; 2706 lf.l_whence = SEEK_SET; 2707 lf.l_start = 0; 2708 lf.l_len = 0; 2709 if (uap->how & LOCK_UN) { 2710 lf.l_type = F_UNLCK; 2711 atomic_clear_int(&fp->f_flag, FHASLOCK); 2712 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); 2713 goto done2; 2714 } 2715 if (uap->how & LOCK_EX) 2716 lf.l_type = F_WRLCK; 2717 else if (uap->how & LOCK_SH) 2718 lf.l_type = F_RDLCK; 2719 else { 2720 error = EBADF; 2721 goto done2; 2722 } 2723 atomic_set_int(&fp->f_flag, FHASLOCK); 2724 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, 2725 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); 2726done2: 2727 fdrop(fp, td); 2728 return (error); 2729} 2730/* 2731 * Duplicate the specified descriptor to a free descriptor. 2732 */ 2733int 2734dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 2735 int openerror, int *indxp) 2736{ 2737 struct file *fp; 2738 int error, indx; 2739 2740 KASSERT(openerror == ENODEV || openerror == ENXIO, 2741 ("unexpected error %d in %s", openerror, __func__)); 2742 2743 /* 2744 * If the to-be-dup'd fd number is greater than the allowed number 2745 * of file descriptors, or the fd to be dup'd has already been 2746 * closed, then reject. 2747 */ 2748 FILEDESC_XLOCK(fdp); 2749 if ((fp = fget_locked(fdp, dfd)) == NULL) { 2750 FILEDESC_XUNLOCK(fdp); 2751 return (EBADF); 2752 } 2753 2754 error = fdalloc(td, 0, &indx); 2755 if (error != 0) { 2756 FILEDESC_XUNLOCK(fdp); 2757 return (error); 2758 } 2759 2760 /* 2761 * There are two cases of interest here. 2762 * 2763 * For ENODEV simply dup (dfd) to file descriptor (indx) and return. 2764 * 2765 * For ENXIO steal away the file structure from (dfd) and store it in 2766 * (indx). (dfd) is effectively closed by this operation. 2767 */ 2768 switch (openerror) { 2769 case ENODEV: 2770 /* 2771 * Check that the mode the file is being opened for is a 2772 * subset of the mode of the existing descriptor. 2773 */ 2774 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { 2775 fdunused(fdp, indx); 2776 FILEDESC_XUNLOCK(fdp); 2777 return (EACCES); 2778 } 2779 fhold(fp); 2780 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2781 filecaps_copy(&fdp->fd_ofiles[dfd].fde_caps, 2782 &fdp->fd_ofiles[indx].fde_caps); 2783 break; 2784 case ENXIO: 2785 /* 2786 * Steal away the file pointer from dfd and stuff it into indx. 2787 */ 2788 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd]; 2789 bzero(&fdp->fd_ofiles[dfd], sizeof(fdp->fd_ofiles[dfd])); 2790 fdunused(fdp, dfd); 2791 break; 2792 } 2793 FILEDESC_XUNLOCK(fdp); 2794 *indxp = indx; 2795 return (0); 2796} 2797 2798/* 2799 * Scan all active processes and prisons to see if any of them have a current 2800 * or root directory of `olddp'. If so, replace them with the new mount point. 2801 */ 2802void 2803mountcheckdirs(struct vnode *olddp, struct vnode *newdp) 2804{ 2805 struct filedesc *fdp; 2806 struct prison *pr; 2807 struct proc *p; 2808 int nrele; 2809 2810 if (vrefcnt(olddp) == 1) 2811 return; 2812 nrele = 0; 2813 sx_slock(&allproc_lock); 2814 FOREACH_PROC_IN_SYSTEM(p) { 2815 fdp = fdhold(p); 2816 if (fdp == NULL) 2817 continue; 2818 FILEDESC_XLOCK(fdp); 2819 if (fdp->fd_cdir == olddp) { 2820 vref(newdp); 2821 fdp->fd_cdir = newdp; 2822 nrele++; 2823 } 2824 if (fdp->fd_rdir == olddp) { 2825 vref(newdp); 2826 fdp->fd_rdir = newdp; 2827 nrele++; 2828 } 2829 if (fdp->fd_jdir == olddp) { 2830 vref(newdp); 2831 fdp->fd_jdir = newdp; 2832 nrele++; 2833 } 2834 FILEDESC_XUNLOCK(fdp); 2835 fddrop(fdp); 2836 } 2837 sx_sunlock(&allproc_lock); 2838 if (rootvnode == olddp) { 2839 vref(newdp); 2840 rootvnode = newdp; 2841 nrele++; 2842 } 2843 mtx_lock(&prison0.pr_mtx); 2844 if (prison0.pr_root == olddp) { 2845 vref(newdp); 2846 prison0.pr_root = newdp; 2847 nrele++; 2848 } 2849 mtx_unlock(&prison0.pr_mtx); 2850 sx_slock(&allprison_lock); 2851 TAILQ_FOREACH(pr, &allprison, pr_list) { 2852 mtx_lock(&pr->pr_mtx); 2853 if (pr->pr_root == olddp) { 2854 vref(newdp); 2855 pr->pr_root = newdp; 2856 nrele++; 2857 } 2858 mtx_unlock(&pr->pr_mtx); 2859 } 2860 sx_sunlock(&allprison_lock); 2861 while (nrele--) 2862 vrele(olddp); 2863} 2864 2865struct filedesc_to_leader * 2866filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) 2867{ 2868 struct filedesc_to_leader *fdtol; 2869 2870 fdtol = malloc(sizeof(struct filedesc_to_leader), 2871 M_FILEDESC_TO_LEADER, 2872 M_WAITOK); 2873 fdtol->fdl_refcount = 1; 2874 fdtol->fdl_holdcount = 0; 2875 fdtol->fdl_wakeup = 0; 2876 fdtol->fdl_leader = leader; 2877 if (old != NULL) { 2878 FILEDESC_XLOCK(fdp); 2879 fdtol->fdl_next = old->fdl_next; 2880 fdtol->fdl_prev = old; 2881 old->fdl_next = fdtol; 2882 fdtol->fdl_next->fdl_prev = fdtol; 2883 FILEDESC_XUNLOCK(fdp); 2884 } else { 2885 fdtol->fdl_next = fdtol; 2886 fdtol->fdl_prev = fdtol; 2887 } 2888 return (fdtol); 2889} 2890 2891/* 2892 * Get file structures globally. 2893 */ 2894static int 2895sysctl_kern_file(SYSCTL_HANDLER_ARGS) 2896{ 2897 struct xfile xf; 2898 struct filedesc *fdp; 2899 struct file *fp; 2900 struct proc *p; 2901 int error, n; 2902 2903 error = sysctl_wire_old_buffer(req, 0); 2904 if (error != 0) 2905 return (error); 2906 if (req->oldptr == NULL) { 2907 n = 0; 2908 sx_slock(&allproc_lock); 2909 FOREACH_PROC_IN_SYSTEM(p) { 2910 if (p->p_state == PRS_NEW) 2911 continue; 2912 fdp = fdhold(p); 2913 if (fdp == NULL) 2914 continue; 2915 /* overestimates sparse tables. */ 2916 if (fdp->fd_lastfile > 0) 2917 n += fdp->fd_lastfile; 2918 fddrop(fdp); 2919 } 2920 sx_sunlock(&allproc_lock); 2921 return (SYSCTL_OUT(req, 0, n * sizeof(xf))); 2922 } 2923 error = 0; 2924 bzero(&xf, sizeof(xf)); 2925 xf.xf_size = sizeof(xf); 2926 sx_slock(&allproc_lock); 2927 FOREACH_PROC_IN_SYSTEM(p) { 2928 PROC_LOCK(p); 2929 if (p->p_state == PRS_NEW) { 2930 PROC_UNLOCK(p); 2931 continue; 2932 } 2933 if (p_cansee(req->td, p) != 0) { 2934 PROC_UNLOCK(p); 2935 continue; 2936 } 2937 xf.xf_pid = p->p_pid; 2938 xf.xf_uid = p->p_ucred->cr_uid; 2939 PROC_UNLOCK(p); 2940 fdp = fdhold(p); 2941 if (fdp == NULL) 2942 continue; 2943 FILEDESC_SLOCK(fdp); 2944 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) { 2945 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 2946 continue; 2947 xf.xf_fd = n; 2948 xf.xf_file = fp; 2949 xf.xf_data = fp->f_data; 2950 xf.xf_vnode = fp->f_vnode; 2951 xf.xf_type = fp->f_type; 2952 xf.xf_count = fp->f_count; 2953 xf.xf_msgcount = 0; 2954 xf.xf_offset = foffset_get(fp); 2955 xf.xf_flag = fp->f_flag; 2956 error = SYSCTL_OUT(req, &xf, sizeof(xf)); 2957 if (error) 2958 break; 2959 } 2960 FILEDESC_SUNLOCK(fdp); 2961 fddrop(fdp); 2962 if (error) 2963 break; 2964 } 2965 sx_sunlock(&allproc_lock); 2966 return (error); 2967} 2968 2969SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD, 2970 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); 2971 2972#ifdef KINFO_OFILE_SIZE 2973CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); 2974#endif 2975 2976#ifdef COMPAT_FREEBSD7 2977static int 2978export_vnode_for_osysctl(struct vnode *vp, int type, 2979 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) 2980{ 2981 int error; 2982 char *fullpath, *freepath; 2983 2984 bzero(kif, sizeof(*kif)); 2985 kif->kf_structsize = sizeof(*kif); 2986 2987 vref(vp); 2988 kif->kf_fd = type; 2989 kif->kf_type = KF_TYPE_VNODE; 2990 /* This function only handles directories. */ 2991 if (vp->v_type != VDIR) { 2992 vrele(vp); 2993 return (ENOTDIR); 2994 } 2995 kif->kf_vnode_type = KF_VTYPE_VDIR; 2996 2997 /* 2998 * This is not a true file descriptor, so we set a bogus refcount 2999 * and offset to indicate these fields should be ignored. 3000 */ 3001 kif->kf_ref_count = -1; 3002 kif->kf_offset = -1; 3003 3004 freepath = NULL; 3005 fullpath = "-"; 3006 FILEDESC_SUNLOCK(fdp); 3007 vn_fullpath(curthread, vp, &fullpath, &freepath); 3008 vrele(vp); 3009 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3010 if (freepath != NULL) 3011 free(freepath, M_TEMP); 3012 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3013 FILEDESC_SLOCK(fdp); 3014 return (error); 3015} 3016 3017/* 3018 * Get per-process file descriptors for use by procstat(1), et al. 3019 */ 3020static int 3021sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) 3022{ 3023 char *fullpath, *freepath; 3024 struct kinfo_ofile *kif; 3025 struct filedesc *fdp; 3026 int error, i, *name; 3027 struct shmfd *shmfd; 3028 struct socket *so; 3029 struct vnode *vp; 3030 struct ksem *ks; 3031 struct file *fp; 3032 struct proc *p; 3033 struct tty *tp; 3034 3035 name = (int *)arg1; 3036 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3037 if (error != 0) 3038 return (error); 3039 fdp = fdhold(p); 3040 PROC_UNLOCK(p); 3041 if (fdp == NULL) 3042 return (ENOENT); 3043 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); 3044 FILEDESC_SLOCK(fdp); 3045 if (fdp->fd_cdir != NULL) 3046 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, 3047 fdp, req); 3048 if (fdp->fd_rdir != NULL) 3049 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, 3050 fdp, req); 3051 if (fdp->fd_jdir != NULL) 3052 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, 3053 fdp, req); 3054 for (i = 0; fdp->fd_refcnt > 0 && i < fdp->fd_nfiles; i++) { 3055 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3056 continue; 3057 bzero(kif, sizeof(*kif)); 3058 kif->kf_structsize = sizeof(*kif); 3059 ks = NULL; 3060 vp = NULL; 3061 so = NULL; 3062 tp = NULL; 3063 shmfd = NULL; 3064 kif->kf_fd = i; 3065 3066 switch (fp->f_type) { 3067 case DTYPE_VNODE: 3068 kif->kf_type = KF_TYPE_VNODE; 3069 vp = fp->f_vnode; 3070 break; 3071 3072 case DTYPE_SOCKET: 3073 kif->kf_type = KF_TYPE_SOCKET; 3074 so = fp->f_data; 3075 break; 3076 3077 case DTYPE_PIPE: 3078 kif->kf_type = KF_TYPE_PIPE; 3079 break; 3080 3081 case DTYPE_FIFO: 3082 kif->kf_type = KF_TYPE_FIFO; 3083 vp = fp->f_vnode; 3084 break; 3085 3086 case DTYPE_KQUEUE: 3087 kif->kf_type = KF_TYPE_KQUEUE; 3088 break; 3089 3090 case DTYPE_CRYPTO: 3091 kif->kf_type = KF_TYPE_CRYPTO; 3092 break; 3093 3094 case DTYPE_MQUEUE: 3095 kif->kf_type = KF_TYPE_MQUEUE; 3096 break; 3097 3098 case DTYPE_SHM: 3099 kif->kf_type = KF_TYPE_SHM; 3100 shmfd = fp->f_data; 3101 break; 3102 3103 case DTYPE_SEM: 3104 kif->kf_type = KF_TYPE_SEM; 3105 ks = fp->f_data; 3106 break; 3107 3108 case DTYPE_PTS: 3109 kif->kf_type = KF_TYPE_PTS; 3110 tp = fp->f_data; 3111 break; 3112 3113#ifdef PROCDESC 3114 case DTYPE_PROCDESC: 3115 kif->kf_type = KF_TYPE_PROCDESC; 3116 break; 3117#endif 3118 3119 default: 3120 kif->kf_type = KF_TYPE_UNKNOWN; 3121 break; 3122 } 3123 kif->kf_ref_count = fp->f_count; 3124 if (fp->f_flag & FREAD) 3125 kif->kf_flags |= KF_FLAG_READ; 3126 if (fp->f_flag & FWRITE) 3127 kif->kf_flags |= KF_FLAG_WRITE; 3128 if (fp->f_flag & FAPPEND) 3129 kif->kf_flags |= KF_FLAG_APPEND; 3130 if (fp->f_flag & FASYNC) 3131 kif->kf_flags |= KF_FLAG_ASYNC; 3132 if (fp->f_flag & FFSYNC) 3133 kif->kf_flags |= KF_FLAG_FSYNC; 3134 if (fp->f_flag & FNONBLOCK) 3135 kif->kf_flags |= KF_FLAG_NONBLOCK; 3136 if (fp->f_flag & O_DIRECT) 3137 kif->kf_flags |= KF_FLAG_DIRECT; 3138 if (fp->f_flag & FHASLOCK) 3139 kif->kf_flags |= KF_FLAG_HASLOCK; 3140 kif->kf_offset = foffset_get(fp); 3141 if (vp != NULL) { 3142 vref(vp); 3143 switch (vp->v_type) { 3144 case VNON: 3145 kif->kf_vnode_type = KF_VTYPE_VNON; 3146 break; 3147 case VREG: 3148 kif->kf_vnode_type = KF_VTYPE_VREG; 3149 break; 3150 case VDIR: 3151 kif->kf_vnode_type = KF_VTYPE_VDIR; 3152 break; 3153 case VBLK: 3154 kif->kf_vnode_type = KF_VTYPE_VBLK; 3155 break; 3156 case VCHR: 3157 kif->kf_vnode_type = KF_VTYPE_VCHR; 3158 break; 3159 case VLNK: 3160 kif->kf_vnode_type = KF_VTYPE_VLNK; 3161 break; 3162 case VSOCK: 3163 kif->kf_vnode_type = KF_VTYPE_VSOCK; 3164 break; 3165 case VFIFO: 3166 kif->kf_vnode_type = KF_VTYPE_VFIFO; 3167 break; 3168 case VBAD: 3169 kif->kf_vnode_type = KF_VTYPE_VBAD; 3170 break; 3171 default: 3172 kif->kf_vnode_type = KF_VTYPE_UNKNOWN; 3173 break; 3174 } 3175 /* 3176 * It is OK to drop the filedesc lock here as we will 3177 * re-validate and re-evaluate its properties when 3178 * the loop continues. 3179 */ 3180 freepath = NULL; 3181 fullpath = "-"; 3182 FILEDESC_SUNLOCK(fdp); 3183 vn_fullpath(curthread, vp, &fullpath, &freepath); 3184 vrele(vp); 3185 strlcpy(kif->kf_path, fullpath, 3186 sizeof(kif->kf_path)); 3187 if (freepath != NULL) 3188 free(freepath, M_TEMP); 3189 FILEDESC_SLOCK(fdp); 3190 } 3191 if (so != NULL) { 3192 struct sockaddr *sa; 3193 3194 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) 3195 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3196 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3197 free(sa, M_SONAME); 3198 } 3199 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) 3200 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3201 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3202 free(sa, M_SONAME); 3203 } 3204 kif->kf_sock_domain = 3205 so->so_proto->pr_domain->dom_family; 3206 kif->kf_sock_type = so->so_type; 3207 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3208 } 3209 if (tp != NULL) { 3210 strlcpy(kif->kf_path, tty_devname(tp), 3211 sizeof(kif->kf_path)); 3212 } 3213 if (shmfd != NULL) 3214 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); 3215 if (ks != NULL && ksem_info != NULL) 3216 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL); 3217 error = SYSCTL_OUT(req, kif, sizeof(*kif)); 3218 if (error) 3219 break; 3220 } 3221 FILEDESC_SUNLOCK(fdp); 3222 fddrop(fdp); 3223 free(kif, M_TEMP); 3224 return (0); 3225} 3226 3227static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD, 3228 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries"); 3229#endif /* COMPAT_FREEBSD7 */ 3230 3231#ifdef KINFO_FILE_SIZE 3232CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 3233#endif 3234 3235struct export_fd_buf { 3236 struct filedesc *fdp; 3237 struct sbuf *sb; 3238 ssize_t remainder; 3239 struct kinfo_file kif; 3240}; 3241 3242static int 3243export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt, 3244 int64_t offset, cap_rights_t *rightsp, struct export_fd_buf *efbuf) 3245{ 3246 struct { 3247 int fflag; 3248 int kf_fflag; 3249 } fflags_table[] = { 3250 { FAPPEND, KF_FLAG_APPEND }, 3251 { FASYNC, KF_FLAG_ASYNC }, 3252 { FFSYNC, KF_FLAG_FSYNC }, 3253 { FHASLOCK, KF_FLAG_HASLOCK }, 3254 { FNONBLOCK, KF_FLAG_NONBLOCK }, 3255 { FREAD, KF_FLAG_READ }, 3256 { FWRITE, KF_FLAG_WRITE }, 3257 { O_CREAT, KF_FLAG_CREAT }, 3258 { O_DIRECT, KF_FLAG_DIRECT }, 3259 { O_EXCL, KF_FLAG_EXCL }, 3260 { O_EXEC, KF_FLAG_EXEC }, 3261 { O_EXLOCK, KF_FLAG_EXLOCK }, 3262 { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, 3263 { O_SHLOCK, KF_FLAG_SHLOCK }, 3264 { O_TRUNC, KF_FLAG_TRUNC } 3265 }; 3266#define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) 3267 struct kinfo_file *kif; 3268 struct vnode *vp; 3269 int error, locked; 3270 unsigned int i; 3271 3272 if (efbuf->remainder == 0) 3273 return (0); 3274 kif = &efbuf->kif; 3275 bzero(kif, sizeof(*kif)); 3276 locked = efbuf->fdp != NULL; 3277 switch (type) { 3278 case KF_TYPE_FIFO: 3279 case KF_TYPE_VNODE: 3280 if (locked) { 3281 FILEDESC_SUNLOCK(efbuf->fdp); 3282 locked = 0; 3283 } 3284 vp = (struct vnode *)data; 3285 error = fill_vnode_info(vp, kif); 3286 vrele(vp); 3287 break; 3288 case KF_TYPE_SOCKET: 3289 error = fill_socket_info((struct socket *)data, kif); 3290 break; 3291 case KF_TYPE_PIPE: 3292 error = fill_pipe_info((struct pipe *)data, kif); 3293 break; 3294 case KF_TYPE_PTS: 3295 error = fill_pts_info((struct tty *)data, kif); 3296 break; 3297 case KF_TYPE_PROCDESC: 3298 error = fill_procdesc_info((struct procdesc *)data, kif); 3299 break; 3300 case KF_TYPE_SEM: 3301 error = fill_sem_info((struct file *)data, kif); 3302 break; 3303 case KF_TYPE_SHM: 3304 error = fill_shm_info((struct file *)data, kif); 3305 break; 3306 default: 3307 error = 0; 3308 } 3309 if (error == 0) 3310 kif->kf_status |= KF_ATTR_VALID; 3311 3312 /* 3313 * Translate file access flags. 3314 */ 3315 for (i = 0; i < NFFLAGS; i++) 3316 if (fflags & fflags_table[i].fflag) 3317 kif->kf_flags |= fflags_table[i].kf_fflag; 3318 if (rightsp != NULL) 3319 kif->kf_cap_rights = *rightsp; 3320 else 3321 cap_rights_init(&kif->kf_cap_rights); 3322 kif->kf_fd = fd; 3323 kif->kf_type = type; 3324 kif->kf_ref_count = refcnt; 3325 kif->kf_offset = offset; 3326 /* Pack record size down */ 3327 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + 3328 strlen(kif->kf_path) + 1; 3329 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); 3330 if (efbuf->remainder != -1) { 3331 if (efbuf->remainder < kif->kf_structsize) { 3332 /* Terminate export. */ 3333 efbuf->remainder = 0; 3334 if (efbuf->fdp != NULL && !locked) 3335 FILEDESC_SLOCK(efbuf->fdp); 3336 return (0); 3337 } 3338 efbuf->remainder -= kif->kf_structsize; 3339 } 3340 if (locked) 3341 FILEDESC_SUNLOCK(efbuf->fdp); 3342 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize); 3343 if (efbuf->fdp != NULL) 3344 FILEDESC_SLOCK(efbuf->fdp); 3345 return (error); 3346} 3347 3348/* 3349 * Store a process file descriptor information to sbuf. 3350 * 3351 * Takes a locked proc as argument, and returns with the proc unlocked. 3352 */ 3353int 3354kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen) 3355{ 3356 struct file *fp; 3357 struct filedesc *fdp; 3358 struct export_fd_buf *efbuf; 3359 struct vnode *cttyvp, *textvp, *tracevp; 3360 int64_t offset; 3361 void *data; 3362 int error, i; 3363 int type, refcnt, fflags; 3364 cap_rights_t rights; 3365 3366 PROC_LOCK_ASSERT(p, MA_OWNED); 3367 3368 /* ktrace vnode */ 3369 tracevp = p->p_tracevp; 3370 if (tracevp != NULL) 3371 vref(tracevp); 3372 /* text vnode */ 3373 textvp = p->p_textvp; 3374 if (textvp != NULL) 3375 vref(textvp); 3376 /* Controlling tty. */ 3377 cttyvp = NULL; 3378 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { 3379 cttyvp = p->p_pgrp->pg_session->s_ttyvp; 3380 if (cttyvp != NULL) 3381 vref(cttyvp); 3382 } 3383 fdp = fdhold(p); 3384 PROC_UNLOCK(p); 3385 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK); 3386 efbuf->fdp = NULL; 3387 efbuf->sb = sb; 3388 efbuf->remainder = maxlen; 3389 if (tracevp != NULL) 3390 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, 3391 FREAD | FWRITE, -1, -1, NULL, efbuf); 3392 if (textvp != NULL) 3393 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, 3394 FREAD, -1, -1, NULL, efbuf); 3395 if (cttyvp != NULL) 3396 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, 3397 FREAD | FWRITE, -1, -1, NULL, efbuf); 3398 error = 0; 3399 if (fdp == NULL) 3400 goto fail; 3401 efbuf->fdp = fdp; 3402 FILEDESC_SLOCK(fdp); 3403 /* working directory */ 3404 if (fdp->fd_cdir != NULL) { 3405 vref(fdp->fd_cdir); 3406 data = fdp->fd_cdir; 3407 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, 3408 FREAD, -1, -1, NULL, efbuf); 3409 } 3410 /* root directory */ 3411 if (fdp->fd_rdir != NULL) { 3412 vref(fdp->fd_rdir); 3413 data = fdp->fd_rdir; 3414 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, 3415 FREAD, -1, -1, NULL, efbuf); 3416 } 3417 /* jail directory */ 3418 if (fdp->fd_jdir != NULL) { 3419 vref(fdp->fd_jdir); 3420 data = fdp->fd_jdir; 3421 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, 3422 FREAD, -1, -1, NULL, efbuf); 3423 } 3424 for (i = 0; fdp->fd_refcnt > 0 && i < fdp->fd_nfiles; i++) { 3425 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL) 3426 continue; 3427 data = NULL; 3428#ifdef CAPABILITIES 3429 rights = *cap_rights(fdp, i); 3430#else /* !CAPABILITIES */ 3431 cap_rights_init(&rights); 3432#endif 3433 switch (fp->f_type) { 3434 case DTYPE_VNODE: 3435 type = KF_TYPE_VNODE; 3436 vref(fp->f_vnode); 3437 data = fp->f_vnode; 3438 break; 3439 3440 case DTYPE_SOCKET: 3441 type = KF_TYPE_SOCKET; 3442 data = fp->f_data; 3443 break; 3444 3445 case DTYPE_PIPE: 3446 type = KF_TYPE_PIPE; 3447 data = fp->f_data; 3448 break; 3449 3450 case DTYPE_FIFO: 3451 type = KF_TYPE_FIFO; 3452 vref(fp->f_vnode); 3453 data = fp->f_vnode; 3454 break; 3455 3456 case DTYPE_KQUEUE: 3457 type = KF_TYPE_KQUEUE; 3458 break; 3459 3460 case DTYPE_CRYPTO: 3461 type = KF_TYPE_CRYPTO; 3462 break; 3463 3464 case DTYPE_MQUEUE: 3465 type = KF_TYPE_MQUEUE; 3466 break; 3467 3468 case DTYPE_SHM: 3469 type = KF_TYPE_SHM; 3470 data = fp; 3471 break; 3472 3473 case DTYPE_SEM: 3474 type = KF_TYPE_SEM; 3475 data = fp; 3476 break; 3477 3478 case DTYPE_PTS: 3479 type = KF_TYPE_PTS; 3480 data = fp->f_data; 3481 break; 3482 3483#ifdef PROCDESC 3484 case DTYPE_PROCDESC: 3485 type = KF_TYPE_PROCDESC; 3486 data = fp->f_data; 3487 break; 3488#endif 3489 3490 default: 3491 type = KF_TYPE_UNKNOWN; 3492 break; 3493 } 3494 refcnt = fp->f_count; 3495 fflags = fp->f_flag; 3496 offset = foffset_get(fp); 3497 3498 /* 3499 * Create sysctl entry. 3500 * It is OK to drop the filedesc lock here as we will 3501 * re-validate and re-evaluate its properties when 3502 * the loop continues. 3503 */ 3504 error = export_fd_to_sb(data, type, i, fflags, refcnt, 3505 offset, &rights, efbuf); 3506 if (error != 0) 3507 break; 3508 } 3509 FILEDESC_SUNLOCK(fdp); 3510 fddrop(fdp); 3511fail: 3512 free(efbuf, M_TEMP); 3513 return (error); 3514} 3515 3516#define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5) 3517 3518/* 3519 * Get per-process file descriptors for use by procstat(1), et al. 3520 */ 3521static int 3522sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) 3523{ 3524 struct sbuf sb; 3525 struct proc *p; 3526 ssize_t maxlen; 3527 int error, error2, *name; 3528 3529 name = (int *)arg1; 3530 3531 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req); 3532 error = pget((pid_t)name[0], PGET_CANDEBUG, &p); 3533 if (error != 0) { 3534 sbuf_delete(&sb); 3535 return (error); 3536 } 3537 maxlen = req->oldptr != NULL ? req->oldlen : -1; 3538 error = kern_proc_filedesc_out(p, &sb, maxlen); 3539 error2 = sbuf_finish(&sb); 3540 sbuf_delete(&sb); 3541 return (error != 0 ? error : error2); 3542} 3543 3544int 3545vntype_to_kinfo(int vtype) 3546{ 3547 struct { 3548 int vtype; 3549 int kf_vtype; 3550 } vtypes_table[] = { 3551 { VBAD, KF_VTYPE_VBAD }, 3552 { VBLK, KF_VTYPE_VBLK }, 3553 { VCHR, KF_VTYPE_VCHR }, 3554 { VDIR, KF_VTYPE_VDIR }, 3555 { VFIFO, KF_VTYPE_VFIFO }, 3556 { VLNK, KF_VTYPE_VLNK }, 3557 { VNON, KF_VTYPE_VNON }, 3558 { VREG, KF_VTYPE_VREG }, 3559 { VSOCK, KF_VTYPE_VSOCK } 3560 }; 3561#define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) 3562 unsigned int i; 3563 3564 /* 3565 * Perform vtype translation. 3566 */ 3567 for (i = 0; i < NVTYPES; i++) 3568 if (vtypes_table[i].vtype == vtype) 3569 break; 3570 if (i < NVTYPES) 3571 return (vtypes_table[i].kf_vtype); 3572 3573 return (KF_VTYPE_UNKNOWN); 3574} 3575 3576static int 3577fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) 3578{ 3579 struct vattr va; 3580 char *fullpath, *freepath; 3581 int error; 3582 3583 if (vp == NULL) 3584 return (1); 3585 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); 3586 freepath = NULL; 3587 fullpath = "-"; 3588 error = vn_fullpath(curthread, vp, &fullpath, &freepath); 3589 if (error == 0) { 3590 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); 3591 } 3592 if (freepath != NULL) 3593 free(freepath, M_TEMP); 3594 3595 /* 3596 * Retrieve vnode attributes. 3597 */ 3598 va.va_fsid = VNOVAL; 3599 va.va_rdev = NODEV; 3600 vn_lock(vp, LK_SHARED | LK_RETRY); 3601 error = VOP_GETATTR(vp, &va, curthread->td_ucred); 3602 VOP_UNLOCK(vp, 0); 3603 if (error != 0) 3604 return (error); 3605 if (va.va_fsid != VNOVAL) 3606 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; 3607 else 3608 kif->kf_un.kf_file.kf_file_fsid = 3609 vp->v_mount->mnt_stat.f_fsid.val[0]; 3610 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; 3611 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); 3612 kif->kf_un.kf_file.kf_file_size = va.va_size; 3613 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; 3614 return (0); 3615} 3616 3617static int 3618fill_socket_info(struct socket *so, struct kinfo_file *kif) 3619{ 3620 struct sockaddr *sa; 3621 struct inpcb *inpcb; 3622 struct unpcb *unpcb; 3623 int error; 3624 3625 if (so == NULL) 3626 return (1); 3627 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; 3628 kif->kf_sock_type = so->so_type; 3629 kif->kf_sock_protocol = so->so_proto->pr_protocol; 3630 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; 3631 switch(kif->kf_sock_domain) { 3632 case AF_INET: 3633 case AF_INET6: 3634 if (kif->kf_sock_protocol == IPPROTO_TCP) { 3635 if (so->so_pcb != NULL) { 3636 inpcb = (struct inpcb *)(so->so_pcb); 3637 kif->kf_un.kf_sock.kf_sock_inpcb = 3638 (uintptr_t)inpcb->inp_ppcb; 3639 } 3640 } 3641 break; 3642 case AF_UNIX: 3643 if (so->so_pcb != NULL) { 3644 unpcb = (struct unpcb *)(so->so_pcb); 3645 if (unpcb->unp_conn) { 3646 kif->kf_un.kf_sock.kf_sock_unpconn = 3647 (uintptr_t)unpcb->unp_conn; 3648 kif->kf_un.kf_sock.kf_sock_rcv_sb_state = 3649 so->so_rcv.sb_state; 3650 kif->kf_un.kf_sock.kf_sock_snd_sb_state = 3651 so->so_snd.sb_state; 3652 } 3653 } 3654 break; 3655 } 3656 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); 3657 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { 3658 bcopy(sa, &kif->kf_sa_local, sa->sa_len); 3659 free(sa, M_SONAME); 3660 } 3661 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); 3662 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { 3663 bcopy(sa, &kif->kf_sa_peer, sa->sa_len); 3664 free(sa, M_SONAME); 3665 } 3666 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, 3667 sizeof(kif->kf_path)); 3668 return (0); 3669} 3670 3671static int 3672fill_pts_info(struct tty *tp, struct kinfo_file *kif) 3673{ 3674 3675 if (tp == NULL) 3676 return (1); 3677 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); 3678 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); 3679 return (0); 3680} 3681 3682static int 3683fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) 3684{ 3685 3686 if (pi == NULL) 3687 return (1); 3688 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; 3689 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; 3690 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; 3691 return (0); 3692} 3693 3694static int 3695fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) 3696{ 3697 3698 if (pdp == NULL) 3699 return (1); 3700 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; 3701 return (0); 3702} 3703 3704static int 3705fill_sem_info(struct file *fp, struct kinfo_file *kif) 3706{ 3707 struct thread *td; 3708 struct stat sb; 3709 3710 td = curthread; 3711 if (fp->f_data == NULL) 3712 return (1); 3713 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3714 return (1); 3715 if (ksem_info == NULL) 3716 return (1); 3717 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path), 3718 &kif->kf_un.kf_sem.kf_sem_value); 3719 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode; 3720 return (0); 3721} 3722 3723static int 3724fill_shm_info(struct file *fp, struct kinfo_file *kif) 3725{ 3726 struct thread *td; 3727 struct stat sb; 3728 3729 td = curthread; 3730 if (fp->f_data == NULL) 3731 return (1); 3732 if (fo_stat(fp, &sb, td->td_ucred, td) != 0) 3733 return (1); 3734 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); 3735 kif->kf_un.kf_file.kf_file_mode = sb.st_mode; 3736 kif->kf_un.kf_file.kf_file_size = sb.st_size; 3737 return (0); 3738} 3739 3740static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD, 3741 sysctl_kern_proc_filedesc, "Process filedesc entries"); 3742 3743#ifdef DDB 3744/* 3745 * For the purposes of debugging, generate a human-readable string for the 3746 * file type. 3747 */ 3748static const char * 3749file_type_to_name(short type) 3750{ 3751 3752 switch (type) { 3753 case 0: 3754 return ("zero"); 3755 case DTYPE_VNODE: 3756 return ("vnod"); 3757 case DTYPE_SOCKET: 3758 return ("sock"); 3759 case DTYPE_PIPE: 3760 return ("pipe"); 3761 case DTYPE_FIFO: 3762 return ("fifo"); 3763 case DTYPE_KQUEUE: 3764 return ("kque"); 3765 case DTYPE_CRYPTO: 3766 return ("crpt"); 3767 case DTYPE_MQUEUE: 3768 return ("mque"); 3769 case DTYPE_SHM: 3770 return ("shm"); 3771 case DTYPE_SEM: 3772 return ("ksem"); 3773 default: 3774 return ("unkn"); 3775 } 3776} 3777 3778/* 3779 * For the purposes of debugging, identify a process (if any, perhaps one of 3780 * many) that references the passed file in its file descriptor array. Return 3781 * NULL if none. 3782 */ 3783static struct proc * 3784file_to_first_proc(struct file *fp) 3785{ 3786 struct filedesc *fdp; 3787 struct proc *p; 3788 int n; 3789 3790 FOREACH_PROC_IN_SYSTEM(p) { 3791 if (p->p_state == PRS_NEW) 3792 continue; 3793 fdp = p->p_fd; 3794 if (fdp == NULL) 3795 continue; 3796 for (n = 0; n < fdp->fd_nfiles; n++) { 3797 if (fp == fdp->fd_ofiles[n].fde_file) 3798 return (p); 3799 } 3800 } 3801 return (NULL); 3802} 3803 3804static void 3805db_print_file(struct file *fp, int header) 3806{ 3807 struct proc *p; 3808 3809 if (header) 3810 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", 3811 "File", "Type", "Data", "Flag", "GCFl", "Count", 3812 "MCount", "Vnode", "FPID", "FCmd"); 3813 p = file_to_first_proc(fp); 3814 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, 3815 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, 3816 0, fp->f_count, 0, fp->f_vnode, 3817 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); 3818} 3819 3820DB_SHOW_COMMAND(file, db_show_file) 3821{ 3822 struct file *fp; 3823 3824 if (!have_addr) { 3825 db_printf("usage: show file <addr>\n"); 3826 return; 3827 } 3828 fp = (struct file *)addr; 3829 db_print_file(fp, 1); 3830} 3831 3832DB_SHOW_COMMAND(files, db_show_files) 3833{ 3834 struct filedesc *fdp; 3835 struct file *fp; 3836 struct proc *p; 3837 int header; 3838 int n; 3839 3840 header = 1; 3841 FOREACH_PROC_IN_SYSTEM(p) { 3842 if (p->p_state == PRS_NEW) 3843 continue; 3844 if ((fdp = p->p_fd) == NULL) 3845 continue; 3846 for (n = 0; n < fdp->fd_nfiles; ++n) { 3847 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL) 3848 continue; 3849 db_print_file(fp, header); 3850 header = 0; 3851 } 3852 } 3853} 3854#endif 3855 3856SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, 3857 &maxfilesperproc, 0, "Maximum files allowed open per process"); 3858 3859SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, 3860 &maxfiles, 0, "Maximum number of files"); 3861 3862SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, 3863 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); 3864 3865/* ARGSUSED*/ 3866static void 3867filelistinit(void *dummy) 3868{ 3869 3870 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, 3871 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 3872 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); 3873 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); 3874} 3875SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); 3876 3877/*-------------------------------------------------------------------*/ 3878 3879static int 3880badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, 3881 int flags, struct thread *td) 3882{ 3883 3884 return (EBADF); 3885} 3886 3887static int 3888badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, 3889 struct thread *td) 3890{ 3891 3892 return (EINVAL); 3893} 3894 3895static int 3896badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, 3897 struct thread *td) 3898{ 3899 3900 return (EBADF); 3901} 3902 3903static int 3904badfo_poll(struct file *fp, int events, struct ucred *active_cred, 3905 struct thread *td) 3906{ 3907 3908 return (0); 3909} 3910 3911static int 3912badfo_kqfilter(struct file *fp, struct knote *kn) 3913{ 3914 3915 return (EBADF); 3916} 3917 3918static int 3919badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, 3920 struct thread *td) 3921{ 3922 3923 return (EBADF); 3924} 3925 3926static int 3927badfo_close(struct file *fp, struct thread *td) 3928{ 3929 3930 return (EBADF); 3931} 3932 3933static int 3934badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3935 struct thread *td) 3936{ 3937 3938 return (EBADF); 3939} 3940 3941static int 3942badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3943 struct thread *td) 3944{ 3945 3946 return (EBADF); 3947} 3948 3949static int 3950badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3951 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3952 int kflags, struct thread *td) 3953{ 3954 3955 return (EBADF); 3956} 3957 3958struct fileops badfileops = { 3959 .fo_read = badfo_readwrite, 3960 .fo_write = badfo_readwrite, 3961 .fo_truncate = badfo_truncate, 3962 .fo_ioctl = badfo_ioctl, 3963 .fo_poll = badfo_poll, 3964 .fo_kqfilter = badfo_kqfilter, 3965 .fo_stat = badfo_stat, 3966 .fo_close = badfo_close, 3967 .fo_chmod = badfo_chmod, 3968 .fo_chown = badfo_chown, 3969 .fo_sendfile = badfo_sendfile, 3970}; 3971 3972int 3973invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, 3974 struct thread *td) 3975{ 3976 3977 return (EINVAL); 3978} 3979 3980int 3981invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, 3982 struct thread *td) 3983{ 3984 3985 return (EINVAL); 3986} 3987 3988int 3989invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, 3990 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, 3991 int kflags, struct thread *td) 3992{ 3993 3994 return (EINVAL); 3995} 3996 3997/*-------------------------------------------------------------------*/ 3998 3999/* 4000 * File Descriptor pseudo-device driver (/dev/fd/). 4001 * 4002 * Opening minor device N dup()s the file (if any) connected to file 4003 * descriptor N belonging to the calling process. Note that this driver 4004 * consists of only the ``open()'' routine, because all subsequent 4005 * references to this file will be direct to the other driver. 4006 * 4007 * XXX: we could give this one a cloning event handler if necessary. 4008 */ 4009 4010/* ARGSUSED */ 4011static int 4012fdopen(struct cdev *dev, int mode, int type, struct thread *td) 4013{ 4014 4015 /* 4016 * XXX Kludge: set curthread->td_dupfd to contain the value of the 4017 * the file descriptor being sought for duplication. The error 4018 * return ensures that the vnode for this device will be released 4019 * by vn_open. Open will detect this special error and take the 4020 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN 4021 * will simply report the error. 4022 */ 4023 td->td_dupfd = dev2unit(dev); 4024 return (ENODEV); 4025} 4026 4027static struct cdevsw fildesc_cdevsw = { 4028 .d_version = D_VERSION, 4029 .d_open = fdopen, 4030 .d_name = "FD", 4031}; 4032 4033static void 4034fildesc_drvinit(void *unused) 4035{ 4036 struct cdev *dev; 4037 4038 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, 4039 UID_ROOT, GID_WHEEL, 0666, "fd/0"); 4040 make_dev_alias(dev, "stdin"); 4041 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, 4042 UID_ROOT, GID_WHEEL, 0666, "fd/1"); 4043 make_dev_alias(dev, "stdout"); 4044 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, 4045 UID_ROOT, GID_WHEEL, 0666, "fd/2"); 4046 make_dev_alias(dev, "stderr"); 4047} 4048 4049SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); 4050