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: releng/10.0/sys/kern/kern_descrip.c 260409 2014-01-07 20:36:15Z mjg $");
39
40 #include "opt_capsicum.h"
41 #include "opt_compat.h"
42 #include "opt_ddb.h"
43 #include "opt_ktrace.h"
44 #include "opt_procdesc.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48
49 #include <sys/capability.h>
50 #include <sys/conf.h>
51 #include <sys/domain.h>
52 #include <sys/fcntl.h>
53 #include <sys/file.h>
54 #include <sys/filedesc.h>
55 #include <sys/filio.h>
56 #include <sys/jail.h>
57 #include <sys/kernel.h>
58 #include <sys/ksem.h>
59 #include <sys/limits.h>
60 #include <sys/lock.h>
61 #include <sys/malloc.h>
62 #include <sys/mman.h>
63 #include <sys/mount.h>
64 #include <sys/mqueue.h>
65 #include <sys/mutex.h>
66 #include <sys/namei.h>
67 #include <sys/selinfo.h>
68 #include <sys/pipe.h>
69 #include <sys/priv.h>
70 #include <sys/proc.h>
71 #include <sys/procdesc.h>
72 #include <sys/protosw.h>
73 #include <sys/racct.h>
74 #include <sys/resourcevar.h>
75 #include <sys/sbuf.h>
76 #include <sys/signalvar.h>
77 #include <sys/socketvar.h>
78 #include <sys/stat.h>
79 #include <sys/sx.h>
80 #include <sys/syscallsubr.h>
81 #include <sys/sysctl.h>
82 #include <sys/sysproto.h>
83 #include <sys/tty.h>
84 #include <sys/unistd.h>
85 #include <sys/un.h>
86 #include <sys/unpcb.h>
87 #include <sys/user.h>
88 #include <sys/vnode.h>
89 #ifdef KTRACE
90 #include <sys/ktrace.h>
91 #endif
92
93 #include <net/vnet.h>
94
95 #include <netinet/in.h>
96 #include <netinet/in_pcb.h>
97
98 #include <security/audit/audit.h>
99
100 #include <vm/uma.h>
101 #include <vm/vm.h>
102
103 #include <ddb/ddb.h>
104
105 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table");
106 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader",
107 "file desc to leader structures");
108 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures");
109 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities");
110
111 MALLOC_DECLARE(M_FADVISE);
112
113 static uma_zone_t file_zone;
114
115 void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value);
116
117 static int closefp(struct filedesc *fdp, int fd, struct file *fp,
118 struct thread *td, int holdleaders);
119 static int fd_first_free(struct filedesc *fdp, int low, int size);
120 static int fd_last_used(struct filedesc *fdp, int size);
121 static void fdgrowtable(struct filedesc *fdp, int nfd);
122 static void fdgrowtable_exp(struct filedesc *fdp, int nfd);
123 static void fdunused(struct filedesc *fdp, int fd);
124 static void fdused(struct filedesc *fdp, int fd);
125 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif);
126 static int fill_procdesc_info(struct procdesc *pdp,
127 struct kinfo_file *kif);
128 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif);
129 static int fill_sem_info(struct file *fp, struct kinfo_file *kif);
130 static int fill_shm_info(struct file *fp, struct kinfo_file *kif);
131 static int fill_socket_info(struct socket *so, struct kinfo_file *kif);
132 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif);
133 static 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 */
168 struct 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 */
177 struct 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 */
187 volatile int openfiles; /* actual number of open files */
188 struct mtx sigio_lock; /* mtx to protect pointers to sigio */
189 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp);
190
191 /* A mutex to protect the association between a proc and filedesc. */
192 static 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 */
199 static int
200 fd_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 */
226 static int
227 fd_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
246 static int
247 fdisused(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 */
261 static void
262 fdused(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 */
279 static void
280 fdunused(struct filedesc *fdp, int fd)
281 {
282
283 FILEDESC_XLOCK_ASSERT(fdp);
284
285 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd));
286 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL,
287 ("fd=%d is still in use", fd));
288
289 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd);
290 if (fd < fdp->fd_freefile)
291 fdp->fd_freefile = fd;
292 if (fd == fdp->fd_lastfile)
293 fdp->fd_lastfile = fd_last_used(fdp, fd);
294 }
295
296 /*
297 * Free a file descriptor.
298 */
299 static inline void
300 fdfree(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_
314 struct getdtablesize_args {
315 int dummy;
316 };
317 #endif
318 /* ARGSUSED */
319 int
320 sys_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_
342 struct dup2_args {
343 u_int from;
344 u_int to;
345 };
346 #endif
347 /* ARGSUSED */
348 int
349 sys_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_
360 struct dup_args {
361 u_int fd;
362 };
363 #endif
364 /* ARGSUSED */
365 int
366 sys_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_
376 struct fcntl_args {
377 int fd;
378 int cmd;
379 long arg;
380 };
381 #endif
382 /* ARGSUSED */
383 int
384 sys_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
451 int
452 kern_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
776 static int
777 getmaxfd(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 */
791 int
792 do_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 *newfde = *oldfde;
883 filecaps_copy(&oldfde->fde_caps, &newfde->fde_caps);
884 if ((flags & DUP_CLOEXEC) != 0)
885 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE;
886 else
887 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE;
888 if (new > fdp->fd_lastfile)
889 fdp->fd_lastfile = new;
890 *retval = new;
891
892 if (delfp != NULL) {
893 (void) closefp(fdp, new, delfp, td, 1);
894 /* closefp() drops the FILEDESC lock for us. */
895 } else {
896 FILEDESC_XUNLOCK(fdp);
897 }
898
899 return (0);
900 }
901
902 /*
903 * If sigio is on the list associated with a process or process group,
904 * disable signalling from the device, remove sigio from the list and
905 * free sigio.
906 */
907 void
908 funsetown(struct sigio **sigiop)
909 {
910 struct sigio *sigio;
911
912 SIGIO_LOCK();
913 sigio = *sigiop;
914 if (sigio == NULL) {
915 SIGIO_UNLOCK();
916 return;
917 }
918 *(sigio->sio_myref) = NULL;
919 if ((sigio)->sio_pgid < 0) {
920 struct pgrp *pg = (sigio)->sio_pgrp;
921 PGRP_LOCK(pg);
922 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio,
923 sigio, sio_pgsigio);
924 PGRP_UNLOCK(pg);
925 } else {
926 struct proc *p = (sigio)->sio_proc;
927 PROC_LOCK(p);
928 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio,
929 sigio, sio_pgsigio);
930 PROC_UNLOCK(p);
931 }
932 SIGIO_UNLOCK();
933 crfree(sigio->sio_ucred);
934 free(sigio, M_SIGIO);
935 }
936
937 /*
938 * Free a list of sigio structures.
939 * We only need to lock the SIGIO_LOCK because we have made ourselves
940 * inaccessible to callers of fsetown and therefore do not need to lock
941 * the proc or pgrp struct for the list manipulation.
942 */
943 void
944 funsetownlst(struct sigiolst *sigiolst)
945 {
946 struct proc *p;
947 struct pgrp *pg;
948 struct sigio *sigio;
949
950 sigio = SLIST_FIRST(sigiolst);
951 if (sigio == NULL)
952 return;
953 p = NULL;
954 pg = NULL;
955
956 /*
957 * Every entry of the list should belong
958 * to a single proc or pgrp.
959 */
960 if (sigio->sio_pgid < 0) {
961 pg = sigio->sio_pgrp;
962 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED);
963 } else /* if (sigio->sio_pgid > 0) */ {
964 p = sigio->sio_proc;
965 PROC_LOCK_ASSERT(p, MA_NOTOWNED);
966 }
967
968 SIGIO_LOCK();
969 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) {
970 *(sigio->sio_myref) = NULL;
971 if (pg != NULL) {
972 KASSERT(sigio->sio_pgid < 0,
973 ("Proc sigio in pgrp sigio list"));
974 KASSERT(sigio->sio_pgrp == pg,
975 ("Bogus pgrp in sigio list"));
976 PGRP_LOCK(pg);
977 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio,
978 sio_pgsigio);
979 PGRP_UNLOCK(pg);
980 } else /* if (p != NULL) */ {
981 KASSERT(sigio->sio_pgid > 0,
982 ("Pgrp sigio in proc sigio list"));
983 KASSERT(sigio->sio_proc == p,
984 ("Bogus proc in sigio list"));
985 PROC_LOCK(p);
986 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio,
987 sio_pgsigio);
988 PROC_UNLOCK(p);
989 }
990 SIGIO_UNLOCK();
991 crfree(sigio->sio_ucred);
992 free(sigio, M_SIGIO);
993 SIGIO_LOCK();
994 }
995 SIGIO_UNLOCK();
996 }
997
998 /*
999 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg).
1000 *
1001 * After permission checking, add a sigio structure to the sigio list for
1002 * the process or process group.
1003 */
1004 int
1005 fsetown(pid_t pgid, struct sigio **sigiop)
1006 {
1007 struct proc *proc;
1008 struct pgrp *pgrp;
1009 struct sigio *sigio;
1010 int ret;
1011
1012 if (pgid == 0) {
1013 funsetown(sigiop);
1014 return (0);
1015 }
1016
1017 ret = 0;
1018
1019 /* Allocate and fill in the new sigio out of locks. */
1020 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK);
1021 sigio->sio_pgid = pgid;
1022 sigio->sio_ucred = crhold(curthread->td_ucred);
1023 sigio->sio_myref = sigiop;
1024
1025 sx_slock(&proctree_lock);
1026 if (pgid > 0) {
1027 proc = pfind(pgid);
1028 if (proc == NULL) {
1029 ret = ESRCH;
1030 goto fail;
1031 }
1032
1033 /*
1034 * Policy - Don't allow a process to FSETOWN a process
1035 * in another session.
1036 *
1037 * Remove this test to allow maximum flexibility or
1038 * restrict FSETOWN to the current process or process
1039 * group for maximum safety.
1040 */
1041 PROC_UNLOCK(proc);
1042 if (proc->p_session != curthread->td_proc->p_session) {
1043 ret = EPERM;
1044 goto fail;
1045 }
1046
1047 pgrp = NULL;
1048 } else /* if (pgid < 0) */ {
1049 pgrp = pgfind(-pgid);
1050 if (pgrp == NULL) {
1051 ret = ESRCH;
1052 goto fail;
1053 }
1054 PGRP_UNLOCK(pgrp);
1055
1056 /*
1057 * Policy - Don't allow a process to FSETOWN a process
1058 * in another session.
1059 *
1060 * Remove this test to allow maximum flexibility or
1061 * restrict FSETOWN to the current process or process
1062 * group for maximum safety.
1063 */
1064 if (pgrp->pg_session != curthread->td_proc->p_session) {
1065 ret = EPERM;
1066 goto fail;
1067 }
1068
1069 proc = NULL;
1070 }
1071 funsetown(sigiop);
1072 if (pgid > 0) {
1073 PROC_LOCK(proc);
1074 /*
1075 * Since funsetownlst() is called without the proctree
1076 * locked, we need to check for P_WEXIT.
1077 * XXX: is ESRCH correct?
1078 */
1079 if ((proc->p_flag & P_WEXIT) != 0) {
1080 PROC_UNLOCK(proc);
1081 ret = ESRCH;
1082 goto fail;
1083 }
1084 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio);
1085 sigio->sio_proc = proc;
1086 PROC_UNLOCK(proc);
1087 } else {
1088 PGRP_LOCK(pgrp);
1089 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio);
1090 sigio->sio_pgrp = pgrp;
1091 PGRP_UNLOCK(pgrp);
1092 }
1093 sx_sunlock(&proctree_lock);
1094 SIGIO_LOCK();
1095 *sigiop = sigio;
1096 SIGIO_UNLOCK();
1097 return (0);
1098
1099 fail:
1100 sx_sunlock(&proctree_lock);
1101 crfree(sigio->sio_ucred);
1102 free(sigio, M_SIGIO);
1103 return (ret);
1104 }
1105
1106 /*
1107 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg).
1108 */
1109 pid_t
1110 fgetown(sigiop)
1111 struct sigio **sigiop;
1112 {
1113 pid_t pgid;
1114
1115 SIGIO_LOCK();
1116 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0;
1117 SIGIO_UNLOCK();
1118 return (pgid);
1119 }
1120
1121 /*
1122 * Function drops the filedesc lock on return.
1123 */
1124 static int
1125 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td,
1126 int holdleaders)
1127 {
1128 int error;
1129
1130 FILEDESC_XLOCK_ASSERT(fdp);
1131
1132 if (holdleaders) {
1133 if (td->td_proc->p_fdtol != NULL) {
1134 /*
1135 * Ask fdfree() to sleep to ensure that all relevant
1136 * process leaders can be traversed in closef().
1137 */
1138 fdp->fd_holdleaderscount++;
1139 } else {
1140 holdleaders = 0;
1141 }
1142 }
1143
1144 /*
1145 * We now hold the fp reference that used to be owned by the
1146 * descriptor array. We have to unlock the FILEDESC *AFTER*
1147 * knote_fdclose to prevent a race of the fd getting opened, a knote
1148 * added, and deleteing a knote for the new fd.
1149 */
1150 knote_fdclose(td, fd);
1151
1152 /*
1153 * We need to notify mqueue if the object is of type mqueue.
1154 */
1155 if (fp->f_type == DTYPE_MQUEUE)
1156 mq_fdclose(td, fd, fp);
1157 FILEDESC_XUNLOCK(fdp);
1158
1159 error = closef(fp, td);
1160 if (holdleaders) {
1161 FILEDESC_XLOCK(fdp);
1162 fdp->fd_holdleaderscount--;
1163 if (fdp->fd_holdleaderscount == 0 &&
1164 fdp->fd_holdleaderswakeup != 0) {
1165 fdp->fd_holdleaderswakeup = 0;
1166 wakeup(&fdp->fd_holdleaderscount);
1167 }
1168 FILEDESC_XUNLOCK(fdp);
1169 }
1170 return (error);
1171 }
1172
1173 /*
1174 * Close a file descriptor.
1175 */
1176 #ifndef _SYS_SYSPROTO_H_
1177 struct close_args {
1178 int fd;
1179 };
1180 #endif
1181 /* ARGSUSED */
1182 int
1183 sys_close(td, uap)
1184 struct thread *td;
1185 struct close_args *uap;
1186 {
1187
1188 return (kern_close(td, uap->fd));
1189 }
1190
1191 int
1192 kern_close(td, fd)
1193 struct thread *td;
1194 int fd;
1195 {
1196 struct filedesc *fdp;
1197 struct file *fp;
1198
1199 fdp = td->td_proc->p_fd;
1200
1201 AUDIT_SYSCLOSE(td, fd);
1202
1203 FILEDESC_XLOCK(fdp);
1204 if ((fp = fget_locked(fdp, fd)) == NULL) {
1205 FILEDESC_XUNLOCK(fdp);
1206 return (EBADF);
1207 }
1208 fdfree(fdp, fd);
1209
1210 /* closefp() drops the FILEDESC lock for us. */
1211 return (closefp(fdp, fd, fp, td, 1));
1212 }
1213
1214 /*
1215 * Close open file descriptors.
1216 */
1217 #ifndef _SYS_SYSPROTO_H_
1218 struct closefrom_args {
1219 int lowfd;
1220 };
1221 #endif
1222 /* ARGSUSED */
1223 int
1224 sys_closefrom(struct thread *td, struct closefrom_args *uap)
1225 {
1226 struct filedesc *fdp;
1227 int fd;
1228
1229 fdp = td->td_proc->p_fd;
1230 AUDIT_ARG_FD(uap->lowfd);
1231
1232 /*
1233 * Treat negative starting file descriptor values identical to
1234 * closefrom(0) which closes all files.
1235 */
1236 if (uap->lowfd < 0)
1237 uap->lowfd = 0;
1238 FILEDESC_SLOCK(fdp);
1239 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) {
1240 if (fdp->fd_ofiles[fd].fde_file != NULL) {
1241 FILEDESC_SUNLOCK(fdp);
1242 (void)kern_close(td, fd);
1243 FILEDESC_SLOCK(fdp);
1244 }
1245 }
1246 FILEDESC_SUNLOCK(fdp);
1247 return (0);
1248 }
1249
1250 #if defined(COMPAT_43)
1251 /*
1252 * Return status information about a file descriptor.
1253 */
1254 #ifndef _SYS_SYSPROTO_H_
1255 struct ofstat_args {
1256 int fd;
1257 struct ostat *sb;
1258 };
1259 #endif
1260 /* ARGSUSED */
1261 int
1262 ofstat(struct thread *td, struct ofstat_args *uap)
1263 {
1264 struct ostat oub;
1265 struct stat ub;
1266 int error;
1267
1268 error = kern_fstat(td, uap->fd, &ub);
1269 if (error == 0) {
1270 cvtstat(&ub, &oub);
1271 error = copyout(&oub, uap->sb, sizeof(oub));
1272 }
1273 return (error);
1274 }
1275 #endif /* COMPAT_43 */
1276
1277 /*
1278 * Return status information about a file descriptor.
1279 */
1280 #ifndef _SYS_SYSPROTO_H_
1281 struct fstat_args {
1282 int fd;
1283 struct stat *sb;
1284 };
1285 #endif
1286 /* ARGSUSED */
1287 int
1288 sys_fstat(struct thread *td, struct fstat_args *uap)
1289 {
1290 struct stat ub;
1291 int error;
1292
1293 error = kern_fstat(td, uap->fd, &ub);
1294 if (error == 0)
1295 error = copyout(&ub, uap->sb, sizeof(ub));
1296 return (error);
1297 }
1298
1299 int
1300 kern_fstat(struct thread *td, int fd, struct stat *sbp)
1301 {
1302 struct file *fp;
1303 cap_rights_t rights;
1304 int error;
1305
1306 AUDIT_ARG_FD(fd);
1307
1308 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp);
1309 if (error != 0)
1310 return (error);
1311
1312 AUDIT_ARG_FILE(td->td_proc, fp);
1313
1314 error = fo_stat(fp, sbp, td->td_ucred, td);
1315 fdrop(fp, td);
1316 #ifdef KTRACE
1317 if (error == 0 && KTRPOINT(td, KTR_STRUCT))
1318 ktrstat(sbp);
1319 #endif
1320 return (error);
1321 }
1322
1323 /*
1324 * Return status information about a file descriptor.
1325 */
1326 #ifndef _SYS_SYSPROTO_H_
1327 struct nfstat_args {
1328 int fd;
1329 struct nstat *sb;
1330 };
1331 #endif
1332 /* ARGSUSED */
1333 int
1334 sys_nfstat(struct thread *td, struct nfstat_args *uap)
1335 {
1336 struct nstat nub;
1337 struct stat ub;
1338 int error;
1339
1340 error = kern_fstat(td, uap->fd, &ub);
1341 if (error == 0) {
1342 cvtnstat(&ub, &nub);
1343 error = copyout(&nub, uap->sb, sizeof(nub));
1344 }
1345 return (error);
1346 }
1347
1348 /*
1349 * Return pathconf information about a file descriptor.
1350 */
1351 #ifndef _SYS_SYSPROTO_H_
1352 struct fpathconf_args {
1353 int fd;
1354 int name;
1355 };
1356 #endif
1357 /* ARGSUSED */
1358 int
1359 sys_fpathconf(struct thread *td, struct fpathconf_args *uap)
1360 {
1361 struct file *fp;
1362 struct vnode *vp;
1363 cap_rights_t rights;
1364 int error;
1365
1366 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp);
1367 if (error != 0)
1368 return (error);
1369
1370 /* If asynchronous I/O is available, it works for all descriptors. */
1371 if (uap->name == _PC_ASYNC_IO) {
1372 td->td_retval[0] = async_io_version;
1373 goto out;
1374 }
1375 vp = fp->f_vnode;
1376 if (vp != NULL) {
1377 vn_lock(vp, LK_SHARED | LK_RETRY);
1378 error = VOP_PATHCONF(vp, uap->name, td->td_retval);
1379 VOP_UNLOCK(vp, 0);
1380 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) {
1381 if (uap->name != _PC_PIPE_BUF) {
1382 error = EINVAL;
1383 } else {
1384 td->td_retval[0] = PIPE_BUF;
1385 error = 0;
1386 }
1387 } else {
1388 error = EOPNOTSUPP;
1389 }
1390 out:
1391 fdrop(fp, td);
1392 return (error);
1393 }
1394
1395 /*
1396 * Initialize filecaps structure.
1397 */
1398 void
1399 filecaps_init(struct filecaps *fcaps)
1400 {
1401
1402 bzero(fcaps, sizeof(*fcaps));
1403 fcaps->fc_nioctls = -1;
1404 }
1405
1406 /*
1407 * Copy filecaps structure allocating memory for ioctls array if needed.
1408 */
1409 void
1410 filecaps_copy(const struct filecaps *src, struct filecaps *dst)
1411 {
1412 size_t size;
1413
1414 *dst = *src;
1415 if (src->fc_ioctls != NULL) {
1416 KASSERT(src->fc_nioctls > 0,
1417 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1418
1419 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1420 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1421 bcopy(src->fc_ioctls, dst->fc_ioctls, size);
1422 }
1423 }
1424
1425 /*
1426 * Move filecaps structure to the new place and clear the old place.
1427 */
1428 void
1429 filecaps_move(struct filecaps *src, struct filecaps *dst)
1430 {
1431
1432 *dst = *src;
1433 bzero(src, sizeof(*src));
1434 }
1435
1436 /*
1437 * Fill the given filecaps structure with full rights.
1438 */
1439 static void
1440 filecaps_fill(struct filecaps *fcaps)
1441 {
1442
1443 CAP_ALL(&fcaps->fc_rights);
1444 fcaps->fc_ioctls = NULL;
1445 fcaps->fc_nioctls = -1;
1446 fcaps->fc_fcntls = CAP_FCNTL_ALL;
1447 }
1448
1449 /*
1450 * Free memory allocated within filecaps structure.
1451 */
1452 void
1453 filecaps_free(struct filecaps *fcaps)
1454 {
1455
1456 free(fcaps->fc_ioctls, M_FILECAPS);
1457 bzero(fcaps, sizeof(*fcaps));
1458 }
1459
1460 /*
1461 * Validate the given filecaps structure.
1462 */
1463 static void
1464 filecaps_validate(const struct filecaps *fcaps, const char *func)
1465 {
1466
1467 KASSERT(cap_rights_is_valid(&fcaps->fc_rights),
1468 ("%s: invalid rights", func));
1469 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0,
1470 ("%s: invalid fcntls", func));
1471 KASSERT(fcaps->fc_fcntls == 0 ||
1472 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL),
1473 ("%s: fcntls without CAP_FCNTL", func));
1474 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 :
1475 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0),
1476 ("%s: invalid ioctls", func));
1477 KASSERT(fcaps->fc_nioctls == 0 ||
1478 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL),
1479 ("%s: ioctls without CAP_IOCTL", func));
1480 }
1481
1482 static void
1483 fdgrowtable_exp(struct filedesc *fdp, int nfd)
1484 {
1485 int nfd1;
1486
1487 FILEDESC_XLOCK_ASSERT(fdp);
1488
1489 nfd1 = fdp->fd_nfiles * 2;
1490 if (nfd1 < nfd)
1491 nfd1 = nfd;
1492 fdgrowtable(fdp, nfd1);
1493 }
1494
1495 /*
1496 * Grow the file table to accomodate (at least) nfd descriptors.
1497 */
1498 static void
1499 fdgrowtable(struct filedesc *fdp, int nfd)
1500 {
1501 struct filedesc0 *fdp0;
1502 struct freetable *ft;
1503 struct filedescent *ntable;
1504 struct filedescent *otable;
1505 int nnfiles, onfiles;
1506 NDSLOTTYPE *nmap, *omap;
1507
1508 FILEDESC_XLOCK_ASSERT(fdp);
1509
1510 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table"));
1511
1512 /* save old values */
1513 onfiles = fdp->fd_nfiles;
1514 otable = fdp->fd_ofiles;
1515 omap = fdp->fd_map;
1516
1517 /* compute the size of the new table */
1518 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */
1519 if (nnfiles <= onfiles)
1520 /* the table is already large enough */
1521 return;
1522
1523 /*
1524 * Allocate a new table and map. We need enough space for the
1525 * file entries themselves and the struct freetable we will use
1526 * when we decommission the table and place it on the freelist.
1527 * We place the struct freetable in the middle so we don't have
1528 * to worry about padding.
1529 */
1530 ntable = malloc(nnfiles * sizeof(ntable[0]) + sizeof(struct freetable),
1531 M_FILEDESC, M_ZERO | M_WAITOK);
1532 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC,
1533 M_ZERO | M_WAITOK);
1534
1535 /* copy the old data over and point at the new tables */
1536 memcpy(ntable, otable, onfiles * sizeof(*otable));
1537 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap));
1538
1539 /* update the pointers and counters */
1540 memcpy(ntable, otable, onfiles * sizeof(ntable[0]));
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 */
1576 int
1577 fdalloc(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 */
1635 int
1636 fdallocn(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 */
1664 int
1665 fdavail(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 */
1696 int
1697 falloc(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 */
1726 int
1727 falloc_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 */
1759 int
1760 finstall(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 */
1794 struct filedesc *
1795 fdinit(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
1826 static struct filedesc *
1827 fdhold(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
1839 static void
1840 fddrop(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 */
1864 struct filedesc *
1865 fdshare(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 */
1877 void
1878 fdunshare(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 */
1897 struct filedesc *
1898 fdcopy(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 */
1950 void
1951 fdescfree(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 */
2090 static int
2091 is_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 */
2105 void
2106 setugidsafety(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 */
2148 void
2149 fdclose(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 */
2164 void
2165 fdcloseexec(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 */
2203 int
2204 fdcheckstd(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 */
2245 int
2246 closef(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 */
2320 void
2321 finit(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
2329 int
2330 fget_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 */
2408 static __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
2475 int
2476 fget(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
2482 int
2483 fget_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
2490 int
2491 fget_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
2497 int
2498 fget_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 */
2511 static __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
2533 int
2534 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2535 {
2536
2537 return (_fgetvp(td, fd, 0, rightsp, vpp));
2538 }
2539
2540 int
2541 fgetvp_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
2575 int
2576 fgetvp_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
2582 int
2583 fgetvp_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
2590 int
2591 fgetvp_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 */
2610 int
2611 fgetsock(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 */
2643 void
2644 fputsock(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 */
2657 int
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_
2682 struct flock_args {
2683 int fd;
2684 int how;
2685 };
2686 #endif
2687 /* ARGSUSED */
2688 int
2689 sys_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);
2726 done2:
2727 fdrop(fp, td);
2728 return (error);
2729 }
2730 /*
2731 * Duplicate the specified descriptor to a free descriptor.
2732 */
2733 int
2734 dupfdopen(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 */
2802 void
2803 mountcheckdirs(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
2865 struct filedesc_to_leader *
2866 filedesc_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 */
2894 static int
2895 sysctl_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
2969 SYSCTL_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
2973 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE);
2974 #endif
2975
2976 #ifdef COMPAT_FREEBSD7
2977 static int
2978 export_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 */
3020 static int
3021 sysctl_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; 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
3227 static 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
3232 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
3233 #endif
3234
3235 struct export_fd_buf {
3236 struct filedesc *fdp;
3237 struct sbuf *sb;
3238 ssize_t remainder;
3239 struct kinfo_file kif;
3240 };
3241
3242 static int
3243 export_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 */
3353 int
3354 kern_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; 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);
3511 fail:
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 */
3521 static int
3522 sysctl_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
3544 int
3545 vntype_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
3576 static int
3577 fill_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
3617 static int
3618 fill_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
3671 static int
3672 fill_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
3682 static int
3683 fill_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
3694 static int
3695 fill_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
3704 static int
3705 fill_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
3723 static int
3724 fill_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
3740 static 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 */
3748 static const char *
3749 file_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 */
3783 static struct proc *
3784 file_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
3804 static void
3805 db_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
3820 DB_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
3832 DB_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
3856 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW,
3857 &maxfilesperproc, 0, "Maximum files allowed open per process");
3858
3859 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW,
3860 &maxfiles, 0, "Maximum number of files");
3861
3862 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD,
3863 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files");
3864
3865 /* ARGSUSED*/
3866 static void
3867 filelistinit(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 }
3875 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL);
3876
3877 /*-------------------------------------------------------------------*/
3878
3879 static int
3880 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred,
3881 int flags, struct thread *td)
3882 {
3883
3884 return (EBADF);
3885 }
3886
3887 static int
3888 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
3889 struct thread *td)
3890 {
3891
3892 return (EINVAL);
3893 }
3894
3895 static int
3896 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
3897 struct thread *td)
3898 {
3899
3900 return (EBADF);
3901 }
3902
3903 static int
3904 badfo_poll(struct file *fp, int events, struct ucred *active_cred,
3905 struct thread *td)
3906 {
3907
3908 return (0);
3909 }
3910
3911 static int
3912 badfo_kqfilter(struct file *fp, struct knote *kn)
3913 {
3914
3915 return (EBADF);
3916 }
3917
3918 static int
3919 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
3920 struct thread *td)
3921 {
3922
3923 return (EBADF);
3924 }
3925
3926 static int
3927 badfo_close(struct file *fp, struct thread *td)
3928 {
3929
3930 return (EBADF);
3931 }
3932
3933 static int
3934 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
3935 struct thread *td)
3936 {
3937
3938 return (EBADF);
3939 }
3940
3941 static int
3942 badfo_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
3949 static int
3950 badfo_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
3958 struct 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
3972 int
3973 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
3974 struct thread *td)
3975 {
3976
3977 return (EINVAL);
3978 }
3979
3980 int
3981 invfo_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
3988 int
3989 invfo_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 */
4011 static int
4012 fdopen(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
4027 static struct cdevsw fildesc_cdevsw = {
4028 .d_version = D_VERSION,
4029 .d_open = fdopen,
4030 .d_name = "FD",
4031 };
4032
4033 static void
4034 fildesc_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
4049 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL);
Cache object: e00f8390a250930724252dc573123154
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