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/9.0/sys/kern/kern_descrip.c 226407 2011-10-15 22:27:59Z rwatson $");
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/limits.h>
59 #include <sys/lock.h>
60 #include <sys/malloc.h>
61 #include <sys/mount.h>
62 #include <sys/mqueue.h>
63 #include <sys/mutex.h>
64 #include <sys/namei.h>
65 #include <sys/selinfo.h>
66 #include <sys/pipe.h>
67 #include <sys/priv.h>
68 #include <sys/proc.h>
69 #include <sys/procdesc.h>
70 #include <sys/protosw.h>
71 #include <sys/racct.h>
72 #include <sys/resourcevar.h>
73 #include <sys/signalvar.h>
74 #include <sys/socketvar.h>
75 #include <sys/stat.h>
76 #include <sys/sx.h>
77 #include <sys/syscallsubr.h>
78 #include <sys/sysctl.h>
79 #include <sys/sysproto.h>
80 #include <sys/tty.h>
81 #include <sys/unistd.h>
82 #include <sys/un.h>
83 #include <sys/unpcb.h>
84 #include <sys/user.h>
85 #include <sys/vnode.h>
86 #ifdef KTRACE
87 #include <sys/ktrace.h>
88 #endif
89
90 #include <net/vnet.h>
91
92 #include <netinet/in.h>
93 #include <netinet/in_pcb.h>
94
95 #include <security/audit/audit.h>
96
97 #include <vm/uma.h>
98 #include <vm/vm.h>
99
100 #include <ddb/ddb.h>
101
102 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table");
103 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader",
104 "file desc to leader structures");
105 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures");
106
107 static uma_zone_t file_zone;
108
109
110 /* Flags for do_dup() */
111 #define DUP_FIXED 0x1 /* Force fixed allocation */
112 #define DUP_FCNTL 0x2 /* fcntl()-style errors */
113
114 static int do_dup(struct thread *td, int flags, int old, int new,
115 register_t *retval);
116 static int fd_first_free(struct filedesc *, int, int);
117 static int fd_last_used(struct filedesc *, int, int);
118 static void fdgrowtable(struct filedesc *, int);
119 static void fdunused(struct filedesc *fdp, int fd);
120 static void fdused(struct filedesc *fdp, int fd);
121 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif);
122 static int fill_socket_info(struct socket *so, struct kinfo_file *kif);
123 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif);
124 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif);
125 static int fill_procdesc_info(struct procdesc *pdp,
126 struct kinfo_file *kif);
127
128 /*
129 * A process is initially started out with NDFILE descriptors stored within
130 * this structure, selected to be enough for typical applications based on
131 * the historical limit of 20 open files (and the usage of descriptors by
132 * shells). If these descriptors are exhausted, a larger descriptor table
133 * may be allocated, up to a process' resource limit; the internal arrays
134 * are then unused.
135 */
136 #define NDFILE 20
137 #define NDSLOTSIZE sizeof(NDSLOTTYPE)
138 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT)
139 #define NDSLOT(x) ((x) / NDENTRIES)
140 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES))
141 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES)
142
143 /*
144 * Storage required per open file descriptor.
145 */
146 #define OFILESIZE (sizeof(struct file *) + sizeof(char))
147
148 /*
149 * Storage to hold unused ofiles that need to be reclaimed.
150 */
151 struct freetable {
152 struct file **ft_table;
153 SLIST_ENTRY(freetable) ft_next;
154 };
155
156 /*
157 * Basic allocation of descriptors:
158 * one of the above, plus arrays for NDFILE descriptors.
159 */
160 struct filedesc0 {
161 struct filedesc fd_fd;
162 /*
163 * ofiles which need to be reclaimed on free.
164 */
165 SLIST_HEAD(,freetable) fd_free;
166 /*
167 * These arrays are used when the number of open files is
168 * <= NDFILE, and are then pointed to by the pointers above.
169 */
170 struct file *fd_dfiles[NDFILE];
171 char fd_dfileflags[NDFILE];
172 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)];
173 };
174
175 /*
176 * Descriptor management.
177 */
178 volatile int openfiles; /* actual number of open files */
179 struct mtx sigio_lock; /* mtx to protect pointers to sigio */
180 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp);
181
182 /* A mutex to protect the association between a proc and filedesc. */
183 static struct mtx fdesc_mtx;
184
185 /*
186 * Find the first zero bit in the given bitmap, starting at low and not
187 * exceeding size - 1.
188 */
189 static int
190 fd_first_free(struct filedesc *fdp, int low, int size)
191 {
192 NDSLOTTYPE *map = fdp->fd_map;
193 NDSLOTTYPE mask;
194 int off, maxoff;
195
196 if (low >= size)
197 return (low);
198
199 off = NDSLOT(low);
200 if (low % NDENTRIES) {
201 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES)));
202 if ((mask &= ~map[off]) != 0UL)
203 return (off * NDENTRIES + ffsl(mask) - 1);
204 ++off;
205 }
206 for (maxoff = NDSLOTS(size); off < maxoff; ++off)
207 if (map[off] != ~0UL)
208 return (off * NDENTRIES + ffsl(~map[off]) - 1);
209 return (size);
210 }
211
212 /*
213 * Find the highest non-zero bit in the given bitmap, starting at low and
214 * not exceeding size - 1.
215 */
216 static int
217 fd_last_used(struct filedesc *fdp, int low, int size)
218 {
219 NDSLOTTYPE *map = fdp->fd_map;
220 NDSLOTTYPE mask;
221 int off, minoff;
222
223 if (low >= size)
224 return (-1);
225
226 off = NDSLOT(size);
227 if (size % NDENTRIES) {
228 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES));
229 if ((mask &= map[off]) != 0)
230 return (off * NDENTRIES + flsl(mask) - 1);
231 --off;
232 }
233 for (minoff = NDSLOT(low); off >= minoff; --off)
234 if (map[off] != 0)
235 return (off * NDENTRIES + flsl(map[off]) - 1);
236 return (low - 1);
237 }
238
239 static int
240 fdisused(struct filedesc *fdp, int fd)
241 {
242 KASSERT(fd >= 0 && fd < fdp->fd_nfiles,
243 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles));
244 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0);
245 }
246
247 /*
248 * Mark a file descriptor as used.
249 */
250 static void
251 fdused(struct filedesc *fdp, int fd)
252 {
253
254 FILEDESC_XLOCK_ASSERT(fdp);
255 KASSERT(!fdisused(fdp, fd),
256 ("fd already used"));
257
258 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd);
259 if (fd > fdp->fd_lastfile)
260 fdp->fd_lastfile = fd;
261 if (fd == fdp->fd_freefile)
262 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles);
263 }
264
265 /*
266 * Mark a file descriptor as unused.
267 */
268 static void
269 fdunused(struct filedesc *fdp, int fd)
270 {
271
272 FILEDESC_XLOCK_ASSERT(fdp);
273 KASSERT(fdisused(fdp, fd),
274 ("fd is already unused"));
275 KASSERT(fdp->fd_ofiles[fd] == NULL,
276 ("fd is still in use"));
277
278 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd);
279 if (fd < fdp->fd_freefile)
280 fdp->fd_freefile = fd;
281 if (fd == fdp->fd_lastfile)
282 fdp->fd_lastfile = fd_last_used(fdp, 0, fd);
283 }
284
285 /*
286 * System calls on descriptors.
287 */
288 #ifndef _SYS_SYSPROTO_H_
289 struct getdtablesize_args {
290 int dummy;
291 };
292 #endif
293 /* ARGSUSED */
294 int
295 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap)
296 {
297 struct proc *p = td->td_proc;
298 uint64_t lim;
299
300 PROC_LOCK(p);
301 td->td_retval[0] =
302 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc);
303 lim = racct_get_limit(td->td_proc, RACCT_NOFILE);
304 PROC_UNLOCK(p);
305 if (lim < td->td_retval[0])
306 td->td_retval[0] = lim;
307 return (0);
308 }
309
310 /*
311 * Duplicate a file descriptor to a particular value.
312 *
313 * Note: keep in mind that a potential race condition exists when closing
314 * descriptors from a shared descriptor table (via rfork).
315 */
316 #ifndef _SYS_SYSPROTO_H_
317 struct dup2_args {
318 u_int from;
319 u_int to;
320 };
321 #endif
322 /* ARGSUSED */
323 int
324 sys_dup2(struct thread *td, struct dup2_args *uap)
325 {
326
327 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to,
328 td->td_retval));
329 }
330
331 /*
332 * Duplicate a file descriptor.
333 */
334 #ifndef _SYS_SYSPROTO_H_
335 struct dup_args {
336 u_int fd;
337 };
338 #endif
339 /* ARGSUSED */
340 int
341 sys_dup(struct thread *td, struct dup_args *uap)
342 {
343
344 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval));
345 }
346
347 /*
348 * The file control system call.
349 */
350 #ifndef _SYS_SYSPROTO_H_
351 struct fcntl_args {
352 int fd;
353 int cmd;
354 long arg;
355 };
356 #endif
357 /* ARGSUSED */
358 int
359 sys_fcntl(struct thread *td, struct fcntl_args *uap)
360 {
361 struct flock fl;
362 struct oflock ofl;
363 intptr_t arg;
364 int error;
365 int cmd;
366
367 error = 0;
368 cmd = uap->cmd;
369 switch (uap->cmd) {
370 case F_OGETLK:
371 case F_OSETLK:
372 case F_OSETLKW:
373 /*
374 * Convert old flock structure to new.
375 */
376 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl));
377 fl.l_start = ofl.l_start;
378 fl.l_len = ofl.l_len;
379 fl.l_pid = ofl.l_pid;
380 fl.l_type = ofl.l_type;
381 fl.l_whence = ofl.l_whence;
382 fl.l_sysid = 0;
383
384 switch (uap->cmd) {
385 case F_OGETLK:
386 cmd = F_GETLK;
387 break;
388 case F_OSETLK:
389 cmd = F_SETLK;
390 break;
391 case F_OSETLKW:
392 cmd = F_SETLKW;
393 break;
394 }
395 arg = (intptr_t)&fl;
396 break;
397 case F_GETLK:
398 case F_SETLK:
399 case F_SETLKW:
400 case F_SETLK_REMOTE:
401 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl));
402 arg = (intptr_t)&fl;
403 break;
404 default:
405 arg = uap->arg;
406 break;
407 }
408 if (error)
409 return (error);
410 error = kern_fcntl(td, uap->fd, cmd, arg);
411 if (error)
412 return (error);
413 if (uap->cmd == F_OGETLK) {
414 ofl.l_start = fl.l_start;
415 ofl.l_len = fl.l_len;
416 ofl.l_pid = fl.l_pid;
417 ofl.l_type = fl.l_type;
418 ofl.l_whence = fl.l_whence;
419 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl));
420 } else if (uap->cmd == F_GETLK) {
421 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl));
422 }
423 return (error);
424 }
425
426 static inline struct file *
427 fdtofp(int fd, struct filedesc *fdp)
428 {
429 struct file *fp;
430
431 FILEDESC_LOCK_ASSERT(fdp);
432 if ((unsigned)fd >= fdp->fd_nfiles ||
433 (fp = fdp->fd_ofiles[fd]) == NULL)
434 return (NULL);
435 return (fp);
436 }
437
438 static inline int
439 fdunwrap(int fd, cap_rights_t rights, struct filedesc *fdp, struct file **fpp)
440 {
441
442 *fpp = fdtofp(fd, fdp);
443 if (*fpp == NULL)
444 return (EBADF);
445
446 #ifdef CAPABILITIES
447 if ((*fpp)->f_type == DTYPE_CAPABILITY) {
448 int err = cap_funwrap(*fpp, rights, fpp);
449 if (err != 0) {
450 *fpp = NULL;
451 return (err);
452 }
453 }
454 #endif /* CAPABILITIES */
455 return (0);
456 }
457
458 int
459 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg)
460 {
461 struct filedesc *fdp;
462 struct flock *flp;
463 struct file *fp;
464 struct proc *p;
465 char *pop;
466 struct vnode *vp;
467 int error, flg, tmp;
468 int vfslocked;
469 u_int old, new;
470 uint64_t bsize;
471
472 vfslocked = 0;
473 error = 0;
474 flg = F_POSIX;
475 p = td->td_proc;
476 fdp = p->p_fd;
477
478 switch (cmd) {
479 case F_DUPFD:
480 tmp = arg;
481 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval);
482 break;
483
484 case F_DUP2FD:
485 tmp = arg;
486 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval);
487 break;
488
489 case F_GETFD:
490 FILEDESC_SLOCK(fdp);
491 if ((fp = fdtofp(fd, fdp)) == NULL) {
492 FILEDESC_SUNLOCK(fdp);
493 error = EBADF;
494 break;
495 }
496 pop = &fdp->fd_ofileflags[fd];
497 td->td_retval[0] = (*pop & UF_EXCLOSE) ? FD_CLOEXEC : 0;
498 FILEDESC_SUNLOCK(fdp);
499 break;
500
501 case F_SETFD:
502 FILEDESC_XLOCK(fdp);
503 if ((fp = fdtofp(fd, fdp)) == NULL) {
504 FILEDESC_XUNLOCK(fdp);
505 error = EBADF;
506 break;
507 }
508 pop = &fdp->fd_ofileflags[fd];
509 *pop = (*pop &~ UF_EXCLOSE) |
510 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0);
511 FILEDESC_XUNLOCK(fdp);
512 break;
513
514 case F_GETFL:
515 FILEDESC_SLOCK(fdp);
516 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
517 if (error != 0) {
518 FILEDESC_SUNLOCK(fdp);
519 break;
520 }
521 td->td_retval[0] = OFLAGS(fp->f_flag);
522 FILEDESC_SUNLOCK(fdp);
523 break;
524
525 case F_SETFL:
526 FILEDESC_SLOCK(fdp);
527 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
528 if (error != 0) {
529 FILEDESC_SUNLOCK(fdp);
530 break;
531 }
532 fhold(fp);
533 FILEDESC_SUNLOCK(fdp);
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) {
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 FILEDESC_SLOCK(fdp);
559 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
560 if (error != 0) {
561 FILEDESC_SUNLOCK(fdp);
562 break;
563 }
564 fhold(fp);
565 FILEDESC_SUNLOCK(fdp);
566 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td);
567 if (error == 0)
568 td->td_retval[0] = tmp;
569 fdrop(fp, td);
570 break;
571
572 case F_SETOWN:
573 FILEDESC_SLOCK(fdp);
574 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
575 if (error != 0) {
576 FILEDESC_SUNLOCK(fdp);
577 break;
578 }
579 fhold(fp);
580 FILEDESC_SUNLOCK(fdp);
581 tmp = arg;
582 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td);
583 fdrop(fp, td);
584 break;
585
586 case F_SETLK_REMOTE:
587 error = priv_check(td, PRIV_NFS_LOCKD);
588 if (error)
589 return (error);
590 flg = F_REMOTE;
591 goto do_setlk;
592
593 case F_SETLKW:
594 flg |= F_WAIT;
595 /* FALLTHROUGH F_SETLK */
596
597 case F_SETLK:
598 do_setlk:
599 FILEDESC_SLOCK(fdp);
600 error = fdunwrap(fd, CAP_FLOCK, fdp, &fp);
601 if (error != 0) {
602 FILEDESC_SUNLOCK(fdp);
603 break;
604 }
605 if (fp->f_type != DTYPE_VNODE) {
606 FILEDESC_SUNLOCK(fdp);
607 error = EBADF;
608 break;
609 }
610 flp = (struct flock *)arg;
611 if (flp->l_whence == SEEK_CUR) {
612 if (fp->f_offset < 0 ||
613 (flp->l_start > 0 &&
614 fp->f_offset > OFF_MAX - flp->l_start)) {
615 FILEDESC_SUNLOCK(fdp);
616 error = EOVERFLOW;
617 break;
618 }
619 flp->l_start += fp->f_offset;
620 }
621
622 /*
623 * VOP_ADVLOCK() may block.
624 */
625 fhold(fp);
626 FILEDESC_SUNLOCK(fdp);
627 vp = fp->f_vnode;
628 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
629 switch (flp->l_type) {
630 case F_RDLCK:
631 if ((fp->f_flag & FREAD) == 0) {
632 error = EBADF;
633 break;
634 }
635 PROC_LOCK(p->p_leader);
636 p->p_leader->p_flag |= P_ADVLOCK;
637 PROC_UNLOCK(p->p_leader);
638 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
639 flp, flg);
640 break;
641 case F_WRLCK:
642 if ((fp->f_flag & FWRITE) == 0) {
643 error = EBADF;
644 break;
645 }
646 PROC_LOCK(p->p_leader);
647 p->p_leader->p_flag |= P_ADVLOCK;
648 PROC_UNLOCK(p->p_leader);
649 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
650 flp, flg);
651 break;
652 case F_UNLCK:
653 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK,
654 flp, flg);
655 break;
656 case F_UNLCKSYS:
657 /*
658 * Temporary api for testing remote lock
659 * infrastructure.
660 */
661 if (flg != F_REMOTE) {
662 error = EINVAL;
663 break;
664 }
665 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
666 F_UNLCKSYS, flp, flg);
667 break;
668 default:
669 error = EINVAL;
670 break;
671 }
672 VFS_UNLOCK_GIANT(vfslocked);
673 vfslocked = 0;
674 /* Check for race with close */
675 FILEDESC_SLOCK(fdp);
676 if ((unsigned) fd >= fdp->fd_nfiles ||
677 fp != fdp->fd_ofiles[fd]) {
678 FILEDESC_SUNLOCK(fdp);
679 flp->l_whence = SEEK_SET;
680 flp->l_start = 0;
681 flp->l_len = 0;
682 flp->l_type = F_UNLCK;
683 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
684 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
685 F_UNLCK, flp, F_POSIX);
686 VFS_UNLOCK_GIANT(vfslocked);
687 vfslocked = 0;
688 } else
689 FILEDESC_SUNLOCK(fdp);
690 fdrop(fp, td);
691 break;
692
693 case F_GETLK:
694 FILEDESC_SLOCK(fdp);
695 error = fdunwrap(fd, CAP_FLOCK, fdp, &fp);
696 if (error != 0) {
697 FILEDESC_SUNLOCK(fdp);
698 break;
699 }
700 if (fp->f_type != DTYPE_VNODE) {
701 FILEDESC_SUNLOCK(fdp);
702 error = EBADF;
703 break;
704 }
705 flp = (struct flock *)arg;
706 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK &&
707 flp->l_type != F_UNLCK) {
708 FILEDESC_SUNLOCK(fdp);
709 error = EINVAL;
710 break;
711 }
712 if (flp->l_whence == SEEK_CUR) {
713 if ((flp->l_start > 0 &&
714 fp->f_offset > OFF_MAX - flp->l_start) ||
715 (flp->l_start < 0 &&
716 fp->f_offset < OFF_MIN - flp->l_start)) {
717 FILEDESC_SUNLOCK(fdp);
718 error = EOVERFLOW;
719 break;
720 }
721 flp->l_start += fp->f_offset;
722 }
723 /*
724 * VOP_ADVLOCK() may block.
725 */
726 fhold(fp);
727 FILEDESC_SUNLOCK(fdp);
728 vp = fp->f_vnode;
729 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
730 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp,
731 F_POSIX);
732 VFS_UNLOCK_GIANT(vfslocked);
733 vfslocked = 0;
734 fdrop(fp, td);
735 break;
736
737 case F_RDAHEAD:
738 arg = arg ? 128 * 1024: 0;
739 /* FALLTHROUGH */
740 case F_READAHEAD:
741 FILEDESC_SLOCK(fdp);
742 if ((fp = fdtofp(fd, fdp)) == NULL) {
743 FILEDESC_SUNLOCK(fdp);
744 error = EBADF;
745 break;
746 }
747 if (fp->f_type != DTYPE_VNODE) {
748 FILEDESC_SUNLOCK(fdp);
749 error = EBADF;
750 break;
751 }
752 fhold(fp);
753 FILEDESC_SUNLOCK(fdp);
754 if (arg != 0) {
755 vp = fp->f_vnode;
756 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
757 error = vn_lock(vp, LK_SHARED);
758 if (error != 0)
759 goto readahead_vnlock_fail;
760 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize;
761 VOP_UNLOCK(vp, 0);
762 fp->f_seqcount = (arg + bsize - 1) / bsize;
763 do {
764 new = old = fp->f_flag;
765 new |= FRDAHEAD;
766 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new));
767 readahead_vnlock_fail:
768 VFS_UNLOCK_GIANT(vfslocked);
769 vfslocked = 0;
770 } else {
771 do {
772 new = old = fp->f_flag;
773 new &= ~FRDAHEAD;
774 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new));
775 }
776 fdrop(fp, td);
777 break;
778
779 default:
780 error = EINVAL;
781 break;
782 }
783 VFS_UNLOCK_GIANT(vfslocked);
784 return (error);
785 }
786
787 /*
788 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD).
789 */
790 static int
791 do_dup(struct thread *td, int flags, int old, int new,
792 register_t *retval)
793 {
794 struct filedesc *fdp;
795 struct proc *p;
796 struct file *fp;
797 struct file *delfp;
798 int error, holdleaders, maxfd;
799
800 p = td->td_proc;
801 fdp = p->p_fd;
802
803 /*
804 * Verify we have a valid descriptor to dup from and possibly to
805 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should
806 * return EINVAL when the new descriptor is out of bounds.
807 */
808 if (old < 0)
809 return (EBADF);
810 if (new < 0)
811 return (flags & DUP_FCNTL ? EINVAL : EBADF);
812 PROC_LOCK(p);
813 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc);
814 PROC_UNLOCK(p);
815 if (new >= maxfd)
816 return (flags & DUP_FCNTL ? EINVAL : EMFILE);
817
818 FILEDESC_XLOCK(fdp);
819 if (old >= fdp->fd_nfiles || fdp->fd_ofiles[old] == NULL) {
820 FILEDESC_XUNLOCK(fdp);
821 return (EBADF);
822 }
823 if (flags & DUP_FIXED && old == new) {
824 *retval = new;
825 FILEDESC_XUNLOCK(fdp);
826 return (0);
827 }
828 fp = fdp->fd_ofiles[old];
829 fhold(fp);
830
831 /*
832 * If the caller specified a file descriptor, make sure the file
833 * table is large enough to hold it, and grab it. Otherwise, just
834 * allocate a new descriptor the usual way. Since the filedesc
835 * lock may be temporarily dropped in the process, we have to look
836 * out for a race.
837 */
838 if (flags & DUP_FIXED) {
839 if (new >= fdp->fd_nfiles) {
840 /*
841 * The resource limits are here instead of e.g. fdalloc(),
842 * because the file descriptor table may be shared between
843 * processes, so we can't really use racct_add()/racct_sub().
844 * Instead of counting the number of actually allocated
845 * descriptors, just put the limit on the size of the file
846 * descriptor table.
847 */
848 #ifdef RACCT
849 PROC_LOCK(p);
850 error = racct_set(p, RACCT_NOFILE, new + 1);
851 PROC_UNLOCK(p);
852 if (error != 0) {
853 FILEDESC_XUNLOCK(fdp);
854 fdrop(fp, td);
855 return (EMFILE);
856 }
857 #endif
858 fdgrowtable(fdp, new + 1);
859 }
860 if (fdp->fd_ofiles[new] == NULL)
861 fdused(fdp, new);
862 } else {
863 if ((error = fdalloc(td, new, &new)) != 0) {
864 FILEDESC_XUNLOCK(fdp);
865 fdrop(fp, td);
866 return (error);
867 }
868 }
869
870 /*
871 * If the old file changed out from under us then treat it as a
872 * bad file descriptor. Userland should do its own locking to
873 * avoid this case.
874 */
875 if (fdp->fd_ofiles[old] != fp) {
876 /* we've allocated a descriptor which we won't use */
877 if (fdp->fd_ofiles[new] == NULL)
878 fdunused(fdp, new);
879 FILEDESC_XUNLOCK(fdp);
880 fdrop(fp, td);
881 return (EBADF);
882 }
883 KASSERT(old != new,
884 ("new fd is same as old"));
885
886 /*
887 * Save info on the descriptor being overwritten. We cannot close
888 * it without introducing an ownership race for the slot, since we
889 * need to drop the filedesc lock to call closef().
890 *
891 * XXX this duplicates parts of close().
892 */
893 delfp = fdp->fd_ofiles[new];
894 holdleaders = 0;
895 if (delfp != NULL) {
896 if (td->td_proc->p_fdtol != NULL) {
897 /*
898 * Ask fdfree() to sleep to ensure that all relevant
899 * process leaders can be traversed in closef().
900 */
901 fdp->fd_holdleaderscount++;
902 holdleaders = 1;
903 }
904 }
905
906 /*
907 * Duplicate the source descriptor
908 */
909 fdp->fd_ofiles[new] = fp;
910 fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] &~ UF_EXCLOSE;
911 if (new > fdp->fd_lastfile)
912 fdp->fd_lastfile = new;
913 *retval = new;
914
915 /*
916 * If we dup'd over a valid file, we now own the reference to it
917 * and must dispose of it using closef() semantics (as if a
918 * close() were performed on it).
919 *
920 * XXX this duplicates parts of close().
921 */
922 if (delfp != NULL) {
923 knote_fdclose(td, new);
924 if (delfp->f_type == DTYPE_MQUEUE)
925 mq_fdclose(td, new, delfp);
926 FILEDESC_XUNLOCK(fdp);
927 (void) closef(delfp, td);
928 if (holdleaders) {
929 FILEDESC_XLOCK(fdp);
930 fdp->fd_holdleaderscount--;
931 if (fdp->fd_holdleaderscount == 0 &&
932 fdp->fd_holdleaderswakeup != 0) {
933 fdp->fd_holdleaderswakeup = 0;
934 wakeup(&fdp->fd_holdleaderscount);
935 }
936 FILEDESC_XUNLOCK(fdp);
937 }
938 } else {
939 FILEDESC_XUNLOCK(fdp);
940 }
941 return (0);
942 }
943
944 /*
945 * If sigio is on the list associated with a process or process group,
946 * disable signalling from the device, remove sigio from the list and
947 * free sigio.
948 */
949 void
950 funsetown(struct sigio **sigiop)
951 {
952 struct sigio *sigio;
953
954 SIGIO_LOCK();
955 sigio = *sigiop;
956 if (sigio == NULL) {
957 SIGIO_UNLOCK();
958 return;
959 }
960 *(sigio->sio_myref) = NULL;
961 if ((sigio)->sio_pgid < 0) {
962 struct pgrp *pg = (sigio)->sio_pgrp;
963 PGRP_LOCK(pg);
964 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio,
965 sigio, sio_pgsigio);
966 PGRP_UNLOCK(pg);
967 } else {
968 struct proc *p = (sigio)->sio_proc;
969 PROC_LOCK(p);
970 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio,
971 sigio, sio_pgsigio);
972 PROC_UNLOCK(p);
973 }
974 SIGIO_UNLOCK();
975 crfree(sigio->sio_ucred);
976 free(sigio, M_SIGIO);
977 }
978
979 /*
980 * Free a list of sigio structures.
981 * We only need to lock the SIGIO_LOCK because we have made ourselves
982 * inaccessible to callers of fsetown and therefore do not need to lock
983 * the proc or pgrp struct for the list manipulation.
984 */
985 void
986 funsetownlst(struct sigiolst *sigiolst)
987 {
988 struct proc *p;
989 struct pgrp *pg;
990 struct sigio *sigio;
991
992 sigio = SLIST_FIRST(sigiolst);
993 if (sigio == NULL)
994 return;
995 p = NULL;
996 pg = NULL;
997
998 /*
999 * Every entry of the list should belong
1000 * to a single proc or pgrp.
1001 */
1002 if (sigio->sio_pgid < 0) {
1003 pg = sigio->sio_pgrp;
1004 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED);
1005 } else /* if (sigio->sio_pgid > 0) */ {
1006 p = sigio->sio_proc;
1007 PROC_LOCK_ASSERT(p, MA_NOTOWNED);
1008 }
1009
1010 SIGIO_LOCK();
1011 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) {
1012 *(sigio->sio_myref) = NULL;
1013 if (pg != NULL) {
1014 KASSERT(sigio->sio_pgid < 0,
1015 ("Proc sigio in pgrp sigio list"));
1016 KASSERT(sigio->sio_pgrp == pg,
1017 ("Bogus pgrp in sigio list"));
1018 PGRP_LOCK(pg);
1019 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio,
1020 sio_pgsigio);
1021 PGRP_UNLOCK(pg);
1022 } else /* if (p != NULL) */ {
1023 KASSERT(sigio->sio_pgid > 0,
1024 ("Pgrp sigio in proc sigio list"));
1025 KASSERT(sigio->sio_proc == p,
1026 ("Bogus proc in sigio list"));
1027 PROC_LOCK(p);
1028 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio,
1029 sio_pgsigio);
1030 PROC_UNLOCK(p);
1031 }
1032 SIGIO_UNLOCK();
1033 crfree(sigio->sio_ucred);
1034 free(sigio, M_SIGIO);
1035 SIGIO_LOCK();
1036 }
1037 SIGIO_UNLOCK();
1038 }
1039
1040 /*
1041 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg).
1042 *
1043 * After permission checking, add a sigio structure to the sigio list for
1044 * the process or process group.
1045 */
1046 int
1047 fsetown(pid_t pgid, struct sigio **sigiop)
1048 {
1049 struct proc *proc;
1050 struct pgrp *pgrp;
1051 struct sigio *sigio;
1052 int ret;
1053
1054 if (pgid == 0) {
1055 funsetown(sigiop);
1056 return (0);
1057 }
1058
1059 ret = 0;
1060
1061 /* Allocate and fill in the new sigio out of locks. */
1062 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK);
1063 sigio->sio_pgid = pgid;
1064 sigio->sio_ucred = crhold(curthread->td_ucred);
1065 sigio->sio_myref = sigiop;
1066
1067 sx_slock(&proctree_lock);
1068 if (pgid > 0) {
1069 proc = pfind(pgid);
1070 if (proc == NULL) {
1071 ret = ESRCH;
1072 goto fail;
1073 }
1074
1075 /*
1076 * Policy - Don't allow a process to FSETOWN a process
1077 * in another session.
1078 *
1079 * Remove this test to allow maximum flexibility or
1080 * restrict FSETOWN to the current process or process
1081 * group for maximum safety.
1082 */
1083 PROC_UNLOCK(proc);
1084 if (proc->p_session != curthread->td_proc->p_session) {
1085 ret = EPERM;
1086 goto fail;
1087 }
1088
1089 pgrp = NULL;
1090 } else /* if (pgid < 0) */ {
1091 pgrp = pgfind(-pgid);
1092 if (pgrp == NULL) {
1093 ret = ESRCH;
1094 goto fail;
1095 }
1096 PGRP_UNLOCK(pgrp);
1097
1098 /*
1099 * Policy - Don't allow a process to FSETOWN a process
1100 * in another session.
1101 *
1102 * Remove this test to allow maximum flexibility or
1103 * restrict FSETOWN to the current process or process
1104 * group for maximum safety.
1105 */
1106 if (pgrp->pg_session != curthread->td_proc->p_session) {
1107 ret = EPERM;
1108 goto fail;
1109 }
1110
1111 proc = NULL;
1112 }
1113 funsetown(sigiop);
1114 if (pgid > 0) {
1115 PROC_LOCK(proc);
1116 /*
1117 * Since funsetownlst() is called without the proctree
1118 * locked, we need to check for P_WEXIT.
1119 * XXX: is ESRCH correct?
1120 */
1121 if ((proc->p_flag & P_WEXIT) != 0) {
1122 PROC_UNLOCK(proc);
1123 ret = ESRCH;
1124 goto fail;
1125 }
1126 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio);
1127 sigio->sio_proc = proc;
1128 PROC_UNLOCK(proc);
1129 } else {
1130 PGRP_LOCK(pgrp);
1131 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio);
1132 sigio->sio_pgrp = pgrp;
1133 PGRP_UNLOCK(pgrp);
1134 }
1135 sx_sunlock(&proctree_lock);
1136 SIGIO_LOCK();
1137 *sigiop = sigio;
1138 SIGIO_UNLOCK();
1139 return (0);
1140
1141 fail:
1142 sx_sunlock(&proctree_lock);
1143 crfree(sigio->sio_ucred);
1144 free(sigio, M_SIGIO);
1145 return (ret);
1146 }
1147
1148 /*
1149 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg).
1150 */
1151 pid_t
1152 fgetown(sigiop)
1153 struct sigio **sigiop;
1154 {
1155 pid_t pgid;
1156
1157 SIGIO_LOCK();
1158 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0;
1159 SIGIO_UNLOCK();
1160 return (pgid);
1161 }
1162
1163 /*
1164 * Close a file descriptor.
1165 */
1166 #ifndef _SYS_SYSPROTO_H_
1167 struct close_args {
1168 int fd;
1169 };
1170 #endif
1171 /* ARGSUSED */
1172 int
1173 sys_close(td, uap)
1174 struct thread *td;
1175 struct close_args *uap;
1176 {
1177
1178 return (kern_close(td, uap->fd));
1179 }
1180
1181 int
1182 kern_close(td, fd)
1183 struct thread *td;
1184 int fd;
1185 {
1186 struct filedesc *fdp;
1187 struct file *fp, *fp_object;
1188 int error;
1189 int holdleaders;
1190
1191 error = 0;
1192 holdleaders = 0;
1193 fdp = td->td_proc->p_fd;
1194
1195 AUDIT_SYSCLOSE(td, fd);
1196
1197 FILEDESC_XLOCK(fdp);
1198 if ((unsigned)fd >= fdp->fd_nfiles ||
1199 (fp = fdp->fd_ofiles[fd]) == NULL) {
1200 FILEDESC_XUNLOCK(fdp);
1201 return (EBADF);
1202 }
1203 fdp->fd_ofiles[fd] = NULL;
1204 fdp->fd_ofileflags[fd] = 0;
1205 fdunused(fdp, fd);
1206 if (td->td_proc->p_fdtol != NULL) {
1207 /*
1208 * Ask fdfree() to sleep to ensure that all relevant
1209 * process leaders can be traversed in closef().
1210 */
1211 fdp->fd_holdleaderscount++;
1212 holdleaders = 1;
1213 }
1214
1215 /*
1216 * We now hold the fp reference that used to be owned by the
1217 * descriptor array. We have to unlock the FILEDESC *AFTER*
1218 * knote_fdclose to prevent a race of the fd getting opened, a knote
1219 * added, and deleteing a knote for the new fd.
1220 */
1221 knote_fdclose(td, fd);
1222
1223 /*
1224 * When we're closing an fd with a capability, we need to notify
1225 * mqueue if the underlying object is of type mqueue.
1226 */
1227 (void)cap_funwrap(fp, 0, &fp_object);
1228 if (fp_object->f_type == DTYPE_MQUEUE)
1229 mq_fdclose(td, fd, fp_object);
1230 FILEDESC_XUNLOCK(fdp);
1231
1232 error = closef(fp, td);
1233 if (holdleaders) {
1234 FILEDESC_XLOCK(fdp);
1235 fdp->fd_holdleaderscount--;
1236 if (fdp->fd_holdleaderscount == 0 &&
1237 fdp->fd_holdleaderswakeup != 0) {
1238 fdp->fd_holdleaderswakeup = 0;
1239 wakeup(&fdp->fd_holdleaderscount);
1240 }
1241 FILEDESC_XUNLOCK(fdp);
1242 }
1243 return (error);
1244 }
1245
1246 /*
1247 * Close open file descriptors.
1248 */
1249 #ifndef _SYS_SYSPROTO_H_
1250 struct closefrom_args {
1251 int lowfd;
1252 };
1253 #endif
1254 /* ARGSUSED */
1255 int
1256 sys_closefrom(struct thread *td, struct closefrom_args *uap)
1257 {
1258 struct filedesc *fdp;
1259 int fd;
1260
1261 fdp = td->td_proc->p_fd;
1262 AUDIT_ARG_FD(uap->lowfd);
1263
1264 /*
1265 * Treat negative starting file descriptor values identical to
1266 * closefrom(0) which closes all files.
1267 */
1268 if (uap->lowfd < 0)
1269 uap->lowfd = 0;
1270 FILEDESC_SLOCK(fdp);
1271 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) {
1272 if (fdp->fd_ofiles[fd] != NULL) {
1273 FILEDESC_SUNLOCK(fdp);
1274 (void)kern_close(td, fd);
1275 FILEDESC_SLOCK(fdp);
1276 }
1277 }
1278 FILEDESC_SUNLOCK(fdp);
1279 return (0);
1280 }
1281
1282 #if defined(COMPAT_43)
1283 /*
1284 * Return status information about a file descriptor.
1285 */
1286 #ifndef _SYS_SYSPROTO_H_
1287 struct ofstat_args {
1288 int fd;
1289 struct ostat *sb;
1290 };
1291 #endif
1292 /* ARGSUSED */
1293 int
1294 ofstat(struct thread *td, struct ofstat_args *uap)
1295 {
1296 struct ostat oub;
1297 struct stat ub;
1298 int error;
1299
1300 error = kern_fstat(td, uap->fd, &ub);
1301 if (error == 0) {
1302 cvtstat(&ub, &oub);
1303 error = copyout(&oub, uap->sb, sizeof(oub));
1304 }
1305 return (error);
1306 }
1307 #endif /* COMPAT_43 */
1308
1309 /*
1310 * Return status information about a file descriptor.
1311 */
1312 #ifndef _SYS_SYSPROTO_H_
1313 struct fstat_args {
1314 int fd;
1315 struct stat *sb;
1316 };
1317 #endif
1318 /* ARGSUSED */
1319 int
1320 sys_fstat(struct thread *td, struct fstat_args *uap)
1321 {
1322 struct stat ub;
1323 int error;
1324
1325 error = kern_fstat(td, uap->fd, &ub);
1326 if (error == 0)
1327 error = copyout(&ub, uap->sb, sizeof(ub));
1328 return (error);
1329 }
1330
1331 int
1332 kern_fstat(struct thread *td, int fd, struct stat *sbp)
1333 {
1334 struct file *fp;
1335 int error;
1336
1337 AUDIT_ARG_FD(fd);
1338
1339 if ((error = fget(td, fd, CAP_FSTAT, &fp)) != 0)
1340 return (error);
1341
1342 AUDIT_ARG_FILE(td->td_proc, fp);
1343
1344 error = fo_stat(fp, sbp, td->td_ucred, td);
1345 fdrop(fp, td);
1346 #ifdef KTRACE
1347 if (error == 0 && KTRPOINT(td, KTR_STRUCT))
1348 ktrstat(sbp);
1349 #endif
1350 return (error);
1351 }
1352
1353 /*
1354 * Return status information about a file descriptor.
1355 */
1356 #ifndef _SYS_SYSPROTO_H_
1357 struct nfstat_args {
1358 int fd;
1359 struct nstat *sb;
1360 };
1361 #endif
1362 /* ARGSUSED */
1363 int
1364 sys_nfstat(struct thread *td, struct nfstat_args *uap)
1365 {
1366 struct nstat nub;
1367 struct stat ub;
1368 int error;
1369
1370 error = kern_fstat(td, uap->fd, &ub);
1371 if (error == 0) {
1372 cvtnstat(&ub, &nub);
1373 error = copyout(&nub, uap->sb, sizeof(nub));
1374 }
1375 return (error);
1376 }
1377
1378 /*
1379 * Return pathconf information about a file descriptor.
1380 */
1381 #ifndef _SYS_SYSPROTO_H_
1382 struct fpathconf_args {
1383 int fd;
1384 int name;
1385 };
1386 #endif
1387 /* ARGSUSED */
1388 int
1389 sys_fpathconf(struct thread *td, struct fpathconf_args *uap)
1390 {
1391 struct file *fp;
1392 struct vnode *vp;
1393 int error;
1394
1395 if ((error = fget(td, uap->fd, CAP_FPATHCONF, &fp)) != 0)
1396 return (error);
1397
1398 /* If asynchronous I/O is available, it works for all descriptors. */
1399 if (uap->name == _PC_ASYNC_IO) {
1400 td->td_retval[0] = async_io_version;
1401 goto out;
1402 }
1403 vp = fp->f_vnode;
1404 if (vp != NULL) {
1405 int vfslocked;
1406 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
1407 vn_lock(vp, LK_SHARED | LK_RETRY);
1408 error = VOP_PATHCONF(vp, uap->name, td->td_retval);
1409 VOP_UNLOCK(vp, 0);
1410 VFS_UNLOCK_GIANT(vfslocked);
1411 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) {
1412 if (uap->name != _PC_PIPE_BUF) {
1413 error = EINVAL;
1414 } else {
1415 td->td_retval[0] = PIPE_BUF;
1416 error = 0;
1417 }
1418 } else {
1419 error = EOPNOTSUPP;
1420 }
1421 out:
1422 fdrop(fp, td);
1423 return (error);
1424 }
1425
1426 /*
1427 * Grow the file table to accomodate (at least) nfd descriptors. This may
1428 * block and drop the filedesc lock, but it will reacquire it before
1429 * returning.
1430 */
1431 static void
1432 fdgrowtable(struct filedesc *fdp, int nfd)
1433 {
1434 struct filedesc0 *fdp0;
1435 struct freetable *fo;
1436 struct file **ntable;
1437 struct file **otable;
1438 char *nfileflags;
1439 int nnfiles, onfiles;
1440 NDSLOTTYPE *nmap;
1441
1442 FILEDESC_XLOCK_ASSERT(fdp);
1443
1444 KASSERT(fdp->fd_nfiles > 0,
1445 ("zero-length file table"));
1446
1447 /* compute the size of the new table */
1448 onfiles = fdp->fd_nfiles;
1449 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */
1450 if (nnfiles <= onfiles)
1451 /* the table is already large enough */
1452 return;
1453
1454 /* allocate a new table and (if required) new bitmaps */
1455 FILEDESC_XUNLOCK(fdp);
1456 ntable = malloc((nnfiles * OFILESIZE) + sizeof(struct freetable),
1457 M_FILEDESC, M_ZERO | M_WAITOK);
1458 nfileflags = (char *)&ntable[nnfiles];
1459 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles))
1460 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE,
1461 M_FILEDESC, M_ZERO | M_WAITOK);
1462 else
1463 nmap = NULL;
1464 FILEDESC_XLOCK(fdp);
1465
1466 /*
1467 * We now have new tables ready to go. Since we dropped the
1468 * filedesc lock to call malloc(), watch out for a race.
1469 */
1470 onfiles = fdp->fd_nfiles;
1471 if (onfiles >= nnfiles) {
1472 /* we lost the race, but that's OK */
1473 free(ntable, M_FILEDESC);
1474 if (nmap != NULL)
1475 free(nmap, M_FILEDESC);
1476 return;
1477 }
1478 bcopy(fdp->fd_ofiles, ntable, onfiles * sizeof(*ntable));
1479 bcopy(fdp->fd_ofileflags, nfileflags, onfiles);
1480 otable = fdp->fd_ofiles;
1481 fdp->fd_ofileflags = nfileflags;
1482 fdp->fd_ofiles = ntable;
1483 /*
1484 * We must preserve ofiles until the process exits because we can't
1485 * be certain that no threads have references to the old table via
1486 * _fget().
1487 */
1488 if (onfiles > NDFILE) {
1489 fo = (struct freetable *)&otable[onfiles];
1490 fdp0 = (struct filedesc0 *)fdp;
1491 fo->ft_table = otable;
1492 SLIST_INSERT_HEAD(&fdp0->fd_free, fo, ft_next);
1493 }
1494 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) {
1495 bcopy(fdp->fd_map, nmap, NDSLOTS(onfiles) * sizeof(*nmap));
1496 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE))
1497 free(fdp->fd_map, M_FILEDESC);
1498 fdp->fd_map = nmap;
1499 }
1500 fdp->fd_nfiles = nnfiles;
1501 }
1502
1503 /*
1504 * Allocate a file descriptor for the process.
1505 */
1506 int
1507 fdalloc(struct thread *td, int minfd, int *result)
1508 {
1509 struct proc *p = td->td_proc;
1510 struct filedesc *fdp = p->p_fd;
1511 int fd = -1, maxfd;
1512 #ifdef RACCT
1513 int error;
1514 #endif
1515
1516 FILEDESC_XLOCK_ASSERT(fdp);
1517
1518 if (fdp->fd_freefile > minfd)
1519 minfd = fdp->fd_freefile;
1520
1521 PROC_LOCK(p);
1522 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc);
1523 PROC_UNLOCK(p);
1524
1525 /*
1526 * Search the bitmap for a free descriptor. If none is found, try
1527 * to grow the file table. Keep at it until we either get a file
1528 * descriptor or run into process or system limits; fdgrowtable()
1529 * may drop the filedesc lock, so we're in a race.
1530 */
1531 for (;;) {
1532 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles);
1533 if (fd >= maxfd)
1534 return (EMFILE);
1535 if (fd < fdp->fd_nfiles)
1536 break;
1537 #ifdef RACCT
1538 PROC_LOCK(p);
1539 error = racct_set(p, RACCT_NOFILE, min(fdp->fd_nfiles * 2, maxfd));
1540 PROC_UNLOCK(p);
1541 if (error != 0)
1542 return (EMFILE);
1543 #endif
1544 fdgrowtable(fdp, min(fdp->fd_nfiles * 2, maxfd));
1545 }
1546
1547 /*
1548 * Perform some sanity checks, then mark the file descriptor as
1549 * used and return it to the caller.
1550 */
1551 KASSERT(!fdisused(fdp, fd),
1552 ("fd_first_free() returned non-free descriptor"));
1553 KASSERT(fdp->fd_ofiles[fd] == NULL,
1554 ("free descriptor isn't"));
1555 fdp->fd_ofileflags[fd] = 0; /* XXX needed? */
1556 fdused(fdp, fd);
1557 *result = fd;
1558 return (0);
1559 }
1560
1561 /*
1562 * Check to see whether n user file descriptors are available to the process
1563 * p.
1564 */
1565 int
1566 fdavail(struct thread *td, int n)
1567 {
1568 struct proc *p = td->td_proc;
1569 struct filedesc *fdp = td->td_proc->p_fd;
1570 struct file **fpp;
1571 int i, lim, last;
1572
1573 FILEDESC_LOCK_ASSERT(fdp);
1574
1575 /*
1576 * XXX: This is only called from uipc_usrreq.c:unp_externalize();
1577 * call racct_add() from there instead of dealing with containers
1578 * here.
1579 */
1580 PROC_LOCK(p);
1581 lim = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc);
1582 PROC_UNLOCK(p);
1583 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0)
1584 return (1);
1585 last = min(fdp->fd_nfiles, lim);
1586 fpp = &fdp->fd_ofiles[fdp->fd_freefile];
1587 for (i = last - fdp->fd_freefile; --i >= 0; fpp++) {
1588 if (*fpp == NULL && --n <= 0)
1589 return (1);
1590 }
1591 return (0);
1592 }
1593
1594 /*
1595 * Create a new open file structure and allocate a file decriptor for the
1596 * process that refers to it. We add one reference to the file for the
1597 * descriptor table and one reference for resultfp. This is to prevent us
1598 * being preempted and the entry in the descriptor table closed after we
1599 * release the FILEDESC lock.
1600 */
1601 int
1602 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags)
1603 {
1604 struct file *fp;
1605 int error, fd;
1606
1607 error = falloc_noinstall(td, &fp);
1608 if (error)
1609 return (error); /* no reference held on error */
1610
1611 error = finstall(td, fp, &fd, flags);
1612 if (error) {
1613 fdrop(fp, td); /* one reference (fp only) */
1614 return (error);
1615 }
1616
1617 if (resultfp != NULL)
1618 *resultfp = fp; /* copy out result */
1619 else
1620 fdrop(fp, td); /* release local reference */
1621
1622 if (resultfd != NULL)
1623 *resultfd = fd;
1624
1625 return (0);
1626 }
1627
1628 /*
1629 * Create a new open file structure without allocating a file descriptor.
1630 */
1631 int
1632 falloc_noinstall(struct thread *td, struct file **resultfp)
1633 {
1634 struct file *fp;
1635 int maxuserfiles = maxfiles - (maxfiles / 20);
1636 static struct timeval lastfail;
1637 static int curfail;
1638
1639 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__));
1640
1641 if ((openfiles >= maxuserfiles &&
1642 priv_check(td, PRIV_MAXFILES) != 0) ||
1643 openfiles >= maxfiles) {
1644 if (ppsratecheck(&lastfail, &curfail, 1)) {
1645 printf("kern.maxfiles limit exceeded by uid %i, "
1646 "please see tuning(7).\n", td->td_ucred->cr_ruid);
1647 }
1648 return (ENFILE);
1649 }
1650 atomic_add_int(&openfiles, 1);
1651 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO);
1652 refcount_init(&fp->f_count, 1);
1653 fp->f_cred = crhold(td->td_ucred);
1654 fp->f_ops = &badfileops;
1655 fp->f_data = NULL;
1656 fp->f_vnode = NULL;
1657 *resultfp = fp;
1658 return (0);
1659 }
1660
1661 /*
1662 * Install a file in a file descriptor table.
1663 */
1664 int
1665 finstall(struct thread *td, struct file *fp, int *fd, int flags)
1666 {
1667 struct filedesc *fdp = td->td_proc->p_fd;
1668 int error;
1669
1670 KASSERT(fd != NULL, ("%s: fd == NULL", __func__));
1671 KASSERT(fp != NULL, ("%s: fp == NULL", __func__));
1672
1673 FILEDESC_XLOCK(fdp);
1674 if ((error = fdalloc(td, 0, fd))) {
1675 FILEDESC_XUNLOCK(fdp);
1676 return (error);
1677 }
1678 fhold(fp);
1679 fdp->fd_ofiles[*fd] = fp;
1680 if ((flags & O_CLOEXEC) != 0)
1681 fdp->fd_ofileflags[*fd] |= UF_EXCLOSE;
1682 FILEDESC_XUNLOCK(fdp);
1683 return (0);
1684 }
1685
1686 /*
1687 * Build a new filedesc structure from another.
1688 * Copy the current, root, and jail root vnode references.
1689 */
1690 struct filedesc *
1691 fdinit(struct filedesc *fdp)
1692 {
1693 struct filedesc0 *newfdp;
1694
1695 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO);
1696 FILEDESC_LOCK_INIT(&newfdp->fd_fd);
1697 if (fdp != NULL) {
1698 FILEDESC_XLOCK(fdp);
1699 newfdp->fd_fd.fd_cdir = fdp->fd_cdir;
1700 if (newfdp->fd_fd.fd_cdir)
1701 VREF(newfdp->fd_fd.fd_cdir);
1702 newfdp->fd_fd.fd_rdir = fdp->fd_rdir;
1703 if (newfdp->fd_fd.fd_rdir)
1704 VREF(newfdp->fd_fd.fd_rdir);
1705 newfdp->fd_fd.fd_jdir = fdp->fd_jdir;
1706 if (newfdp->fd_fd.fd_jdir)
1707 VREF(newfdp->fd_fd.fd_jdir);
1708 FILEDESC_XUNLOCK(fdp);
1709 }
1710
1711 /* Create the file descriptor table. */
1712 newfdp->fd_fd.fd_refcnt = 1;
1713 newfdp->fd_fd.fd_holdcnt = 1;
1714 newfdp->fd_fd.fd_cmask = CMASK;
1715 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles;
1716 newfdp->fd_fd.fd_ofileflags = newfdp->fd_dfileflags;
1717 newfdp->fd_fd.fd_nfiles = NDFILE;
1718 newfdp->fd_fd.fd_map = newfdp->fd_dmap;
1719 newfdp->fd_fd.fd_lastfile = -1;
1720 return (&newfdp->fd_fd);
1721 }
1722
1723 static struct filedesc *
1724 fdhold(struct proc *p)
1725 {
1726 struct filedesc *fdp;
1727
1728 mtx_lock(&fdesc_mtx);
1729 fdp = p->p_fd;
1730 if (fdp != NULL)
1731 fdp->fd_holdcnt++;
1732 mtx_unlock(&fdesc_mtx);
1733 return (fdp);
1734 }
1735
1736 static void
1737 fddrop(struct filedesc *fdp)
1738 {
1739 struct filedesc0 *fdp0;
1740 struct freetable *ft;
1741 int i;
1742
1743 mtx_lock(&fdesc_mtx);
1744 i = --fdp->fd_holdcnt;
1745 mtx_unlock(&fdesc_mtx);
1746 if (i > 0)
1747 return;
1748
1749 FILEDESC_LOCK_DESTROY(fdp);
1750 fdp0 = (struct filedesc0 *)fdp;
1751 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) {
1752 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next);
1753 free(ft->ft_table, M_FILEDESC);
1754 }
1755 free(fdp, M_FILEDESC);
1756 }
1757
1758 /*
1759 * Share a filedesc structure.
1760 */
1761 struct filedesc *
1762 fdshare(struct filedesc *fdp)
1763 {
1764
1765 FILEDESC_XLOCK(fdp);
1766 fdp->fd_refcnt++;
1767 FILEDESC_XUNLOCK(fdp);
1768 return (fdp);
1769 }
1770
1771 /*
1772 * Unshare a filedesc structure, if necessary by making a copy
1773 */
1774 void
1775 fdunshare(struct proc *p, struct thread *td)
1776 {
1777
1778 FILEDESC_XLOCK(p->p_fd);
1779 if (p->p_fd->fd_refcnt > 1) {
1780 struct filedesc *tmp;
1781
1782 FILEDESC_XUNLOCK(p->p_fd);
1783 tmp = fdcopy(p->p_fd);
1784 fdfree(td);
1785 p->p_fd = tmp;
1786 } else
1787 FILEDESC_XUNLOCK(p->p_fd);
1788 }
1789
1790 /*
1791 * Copy a filedesc structure. A NULL pointer in returns a NULL reference,
1792 * this is to ease callers, not catch errors.
1793 */
1794 struct filedesc *
1795 fdcopy(struct filedesc *fdp)
1796 {
1797 struct filedesc *newfdp;
1798 int i;
1799
1800 /* Certain daemons might not have file descriptors. */
1801 if (fdp == NULL)
1802 return (NULL);
1803
1804 newfdp = fdinit(fdp);
1805 FILEDESC_SLOCK(fdp);
1806 while (fdp->fd_lastfile >= newfdp->fd_nfiles) {
1807 FILEDESC_SUNLOCK(fdp);
1808 FILEDESC_XLOCK(newfdp);
1809 fdgrowtable(newfdp, fdp->fd_lastfile + 1);
1810 FILEDESC_XUNLOCK(newfdp);
1811 FILEDESC_SLOCK(fdp);
1812 }
1813 /* copy all passable descriptors (i.e. not kqueue) */
1814 newfdp->fd_freefile = -1;
1815 for (i = 0; i <= fdp->fd_lastfile; ++i) {
1816 if (fdisused(fdp, i) &&
1817 (fdp->fd_ofiles[i]->f_ops->fo_flags & DFLAG_PASSABLE) &&
1818 fdp->fd_ofiles[i]->f_ops != &badfileops) {
1819 newfdp->fd_ofiles[i] = fdp->fd_ofiles[i];
1820 newfdp->fd_ofileflags[i] = fdp->fd_ofileflags[i];
1821 fhold(newfdp->fd_ofiles[i]);
1822 newfdp->fd_lastfile = i;
1823 } else {
1824 if (newfdp->fd_freefile == -1)
1825 newfdp->fd_freefile = i;
1826 }
1827 }
1828 newfdp->fd_cmask = fdp->fd_cmask;
1829 FILEDESC_SUNLOCK(fdp);
1830 FILEDESC_XLOCK(newfdp);
1831 for (i = 0; i <= newfdp->fd_lastfile; ++i)
1832 if (newfdp->fd_ofiles[i] != NULL)
1833 fdused(newfdp, i);
1834 if (newfdp->fd_freefile == -1)
1835 newfdp->fd_freefile = i;
1836 FILEDESC_XUNLOCK(newfdp);
1837 return (newfdp);
1838 }
1839
1840 /*
1841 * Release a filedesc structure.
1842 */
1843 void
1844 fdfree(struct thread *td)
1845 {
1846 struct filedesc *fdp;
1847 struct file **fpp;
1848 int i, locked;
1849 struct filedesc_to_leader *fdtol;
1850 struct file *fp;
1851 struct vnode *cdir, *jdir, *rdir, *vp;
1852 struct flock lf;
1853
1854 /* Certain daemons might not have file descriptors. */
1855 fdp = td->td_proc->p_fd;
1856 if (fdp == NULL)
1857 return;
1858
1859 #ifdef RACCT
1860 PROC_LOCK(td->td_proc);
1861 racct_set(td->td_proc, RACCT_NOFILE, 0);
1862 PROC_UNLOCK(td->td_proc);
1863 #endif
1864
1865 /* Check for special need to clear POSIX style locks */
1866 fdtol = td->td_proc->p_fdtol;
1867 if (fdtol != NULL) {
1868 FILEDESC_XLOCK(fdp);
1869 KASSERT(fdtol->fdl_refcount > 0,
1870 ("filedesc_to_refcount botch: fdl_refcount=%d",
1871 fdtol->fdl_refcount));
1872 if (fdtol->fdl_refcount == 1 &&
1873 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
1874 for (i = 0, fpp = fdp->fd_ofiles;
1875 i <= fdp->fd_lastfile;
1876 i++, fpp++) {
1877 if (*fpp == NULL ||
1878 (*fpp)->f_type != DTYPE_VNODE)
1879 continue;
1880 fp = *fpp;
1881 fhold(fp);
1882 FILEDESC_XUNLOCK(fdp);
1883 lf.l_whence = SEEK_SET;
1884 lf.l_start = 0;
1885 lf.l_len = 0;
1886 lf.l_type = F_UNLCK;
1887 vp = fp->f_vnode;
1888 locked = VFS_LOCK_GIANT(vp->v_mount);
1889 (void) VOP_ADVLOCK(vp,
1890 (caddr_t)td->td_proc->
1891 p_leader,
1892 F_UNLCK,
1893 &lf,
1894 F_POSIX);
1895 VFS_UNLOCK_GIANT(locked);
1896 FILEDESC_XLOCK(fdp);
1897 fdrop(fp, td);
1898 fpp = fdp->fd_ofiles + i;
1899 }
1900 }
1901 retry:
1902 if (fdtol->fdl_refcount == 1) {
1903 if (fdp->fd_holdleaderscount > 0 &&
1904 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
1905 /*
1906 * close() or do_dup() has cleared a reference
1907 * in a shared file descriptor table.
1908 */
1909 fdp->fd_holdleaderswakeup = 1;
1910 sx_sleep(&fdp->fd_holdleaderscount,
1911 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0);
1912 goto retry;
1913 }
1914 if (fdtol->fdl_holdcount > 0) {
1915 /*
1916 * Ensure that fdtol->fdl_leader remains
1917 * valid in closef().
1918 */
1919 fdtol->fdl_wakeup = 1;
1920 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK,
1921 "fdlhold", 0);
1922 goto retry;
1923 }
1924 }
1925 fdtol->fdl_refcount--;
1926 if (fdtol->fdl_refcount == 0 &&
1927 fdtol->fdl_holdcount == 0) {
1928 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev;
1929 fdtol->fdl_prev->fdl_next = fdtol->fdl_next;
1930 } else
1931 fdtol = NULL;
1932 td->td_proc->p_fdtol = NULL;
1933 FILEDESC_XUNLOCK(fdp);
1934 if (fdtol != NULL)
1935 free(fdtol, M_FILEDESC_TO_LEADER);
1936 }
1937 FILEDESC_XLOCK(fdp);
1938 i = --fdp->fd_refcnt;
1939 FILEDESC_XUNLOCK(fdp);
1940 if (i > 0)
1941 return;
1942
1943 fpp = fdp->fd_ofiles;
1944 for (i = fdp->fd_lastfile; i-- >= 0; fpp++) {
1945 if (*fpp) {
1946 FILEDESC_XLOCK(fdp);
1947 fp = *fpp;
1948 *fpp = NULL;
1949 FILEDESC_XUNLOCK(fdp);
1950 (void) closef(fp, td);
1951 }
1952 }
1953 FILEDESC_XLOCK(fdp);
1954
1955 /* XXX This should happen earlier. */
1956 mtx_lock(&fdesc_mtx);
1957 td->td_proc->p_fd = NULL;
1958 mtx_unlock(&fdesc_mtx);
1959
1960 if (fdp->fd_nfiles > NDFILE)
1961 free(fdp->fd_ofiles, M_FILEDESC);
1962 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE))
1963 free(fdp->fd_map, M_FILEDESC);
1964
1965 fdp->fd_nfiles = 0;
1966
1967 cdir = fdp->fd_cdir;
1968 fdp->fd_cdir = NULL;
1969 rdir = fdp->fd_rdir;
1970 fdp->fd_rdir = NULL;
1971 jdir = fdp->fd_jdir;
1972 fdp->fd_jdir = NULL;
1973 FILEDESC_XUNLOCK(fdp);
1974
1975 if (cdir) {
1976 locked = VFS_LOCK_GIANT(cdir->v_mount);
1977 vrele(cdir);
1978 VFS_UNLOCK_GIANT(locked);
1979 }
1980 if (rdir) {
1981 locked = VFS_LOCK_GIANT(rdir->v_mount);
1982 vrele(rdir);
1983 VFS_UNLOCK_GIANT(locked);
1984 }
1985 if (jdir) {
1986 locked = VFS_LOCK_GIANT(jdir->v_mount);
1987 vrele(jdir);
1988 VFS_UNLOCK_GIANT(locked);
1989 }
1990
1991 fddrop(fdp);
1992 }
1993
1994 /*
1995 * For setugid programs, we don't want to people to use that setugidness
1996 * to generate error messages which write to a file which otherwise would
1997 * otherwise be off-limits to the process. We check for filesystems where
1998 * the vnode can change out from under us after execve (like [lin]procfs).
1999 *
2000 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is
2001 * sufficient. We also don't check for setugidness since we know we are.
2002 */
2003 static int
2004 is_unsafe(struct file *fp)
2005 {
2006 if (fp->f_type == DTYPE_VNODE) {
2007 struct vnode *vp = fp->f_vnode;
2008
2009 if ((vp->v_vflag & VV_PROCDEP) != 0)
2010 return (1);
2011 }
2012 return (0);
2013 }
2014
2015 /*
2016 * Make this setguid thing safe, if at all possible.
2017 */
2018 void
2019 setugidsafety(struct thread *td)
2020 {
2021 struct filedesc *fdp;
2022 int i;
2023
2024 /* Certain daemons might not have file descriptors. */
2025 fdp = td->td_proc->p_fd;
2026 if (fdp == NULL)
2027 return;
2028
2029 /*
2030 * Note: fdp->fd_ofiles may be reallocated out from under us while
2031 * we are blocked in a close. Be careful!
2032 */
2033 FILEDESC_XLOCK(fdp);
2034 for (i = 0; i <= fdp->fd_lastfile; i++) {
2035 if (i > 2)
2036 break;
2037 if (fdp->fd_ofiles[i] && is_unsafe(fdp->fd_ofiles[i])) {
2038 struct file *fp;
2039
2040 knote_fdclose(td, i);
2041 /*
2042 * NULL-out descriptor prior to close to avoid
2043 * a race while close blocks.
2044 */
2045 fp = fdp->fd_ofiles[i];
2046 fdp->fd_ofiles[i] = NULL;
2047 fdp->fd_ofileflags[i] = 0;
2048 fdunused(fdp, i);
2049 FILEDESC_XUNLOCK(fdp);
2050 (void) closef(fp, td);
2051 FILEDESC_XLOCK(fdp);
2052 }
2053 }
2054 FILEDESC_XUNLOCK(fdp);
2055 }
2056
2057 /*
2058 * If a specific file object occupies a specific file descriptor, close the
2059 * file descriptor entry and drop a reference on the file object. This is a
2060 * convenience function to handle a subsequent error in a function that calls
2061 * falloc() that handles the race that another thread might have closed the
2062 * file descriptor out from under the thread creating the file object.
2063 */
2064 void
2065 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td)
2066 {
2067
2068 FILEDESC_XLOCK(fdp);
2069 if (fdp->fd_ofiles[idx] == fp) {
2070 fdp->fd_ofiles[idx] = NULL;
2071 fdunused(fdp, idx);
2072 FILEDESC_XUNLOCK(fdp);
2073 fdrop(fp, td);
2074 } else
2075 FILEDESC_XUNLOCK(fdp);
2076 }
2077
2078 /*
2079 * Close any files on exec?
2080 */
2081 void
2082 fdcloseexec(struct thread *td)
2083 {
2084 struct filedesc *fdp;
2085 int i;
2086
2087 /* Certain daemons might not have file descriptors. */
2088 fdp = td->td_proc->p_fd;
2089 if (fdp == NULL)
2090 return;
2091
2092 FILEDESC_XLOCK(fdp);
2093
2094 /*
2095 * We cannot cache fd_ofiles or fd_ofileflags since operations
2096 * may block and rip them out from under us.
2097 */
2098 for (i = 0; i <= fdp->fd_lastfile; i++) {
2099 if (fdp->fd_ofiles[i] != NULL &&
2100 (fdp->fd_ofiles[i]->f_type == DTYPE_MQUEUE ||
2101 (fdp->fd_ofileflags[i] & UF_EXCLOSE))) {
2102 struct file *fp;
2103
2104 knote_fdclose(td, i);
2105 /*
2106 * NULL-out descriptor prior to close to avoid
2107 * a race while close blocks.
2108 */
2109 fp = fdp->fd_ofiles[i];
2110 fdp->fd_ofiles[i] = NULL;
2111 fdp->fd_ofileflags[i] = 0;
2112 fdunused(fdp, i);
2113 if (fp->f_type == DTYPE_MQUEUE)
2114 mq_fdclose(td, i, fp);
2115 FILEDESC_XUNLOCK(fdp);
2116 (void) closef(fp, td);
2117 FILEDESC_XLOCK(fdp);
2118 }
2119 }
2120 FILEDESC_XUNLOCK(fdp);
2121 }
2122
2123 /*
2124 * It is unsafe for set[ug]id processes to be started with file
2125 * descriptors 0..2 closed, as these descriptors are given implicit
2126 * significance in the Standard C library. fdcheckstd() will create a
2127 * descriptor referencing /dev/null for each of stdin, stdout, and
2128 * stderr that is not already open.
2129 */
2130 int
2131 fdcheckstd(struct thread *td)
2132 {
2133 struct filedesc *fdp;
2134 register_t retval, save;
2135 int i, error, devnull;
2136
2137 fdp = td->td_proc->p_fd;
2138 if (fdp == NULL)
2139 return (0);
2140 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2141 devnull = -1;
2142 error = 0;
2143 for (i = 0; i < 3; i++) {
2144 if (fdp->fd_ofiles[i] != NULL)
2145 continue;
2146 if (devnull < 0) {
2147 save = td->td_retval[0];
2148 error = kern_open(td, "/dev/null", UIO_SYSSPACE,
2149 O_RDWR, 0);
2150 devnull = td->td_retval[0];
2151 td->td_retval[0] = save;
2152 if (error)
2153 break;
2154 KASSERT(devnull == i, ("oof, we didn't get our fd"));
2155 } else {
2156 error = do_dup(td, DUP_FIXED, devnull, i, &retval);
2157 if (error != 0)
2158 break;
2159 }
2160 }
2161 return (error);
2162 }
2163
2164 /*
2165 * Internal form of close. Decrement reference count on file structure.
2166 * Note: td may be NULL when closing a file that was being passed in a
2167 * message.
2168 *
2169 * XXXRW: Giant is not required for the caller, but often will be held; this
2170 * makes it moderately likely the Giant will be recursed in the VFS case.
2171 */
2172 int
2173 closef(struct file *fp, struct thread *td)
2174 {
2175 struct vnode *vp;
2176 struct flock lf;
2177 struct filedesc_to_leader *fdtol;
2178 struct filedesc *fdp;
2179 struct file *fp_object;
2180
2181 /*
2182 * POSIX record locking dictates that any close releases ALL
2183 * locks owned by this process. This is handled by setting
2184 * a flag in the unlock to free ONLY locks obeying POSIX
2185 * semantics, and not to free BSD-style file locks.
2186 * If the descriptor was in a message, POSIX-style locks
2187 * aren't passed with the descriptor, and the thread pointer
2188 * will be NULL. Callers should be careful only to pass a
2189 * NULL thread pointer when there really is no owning
2190 * context that might have locks, or the locks will be
2191 * leaked.
2192 *
2193 * If this is a capability, we do lock processing under the underlying
2194 * node, not the capability itself.
2195 */
2196 (void)cap_funwrap(fp, 0, &fp_object);
2197 if ((fp_object->f_type == DTYPE_VNODE) && (td != NULL)) {
2198 int vfslocked;
2199
2200 vp = fp_object->f_vnode;
2201 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
2202 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
2203 lf.l_whence = SEEK_SET;
2204 lf.l_start = 0;
2205 lf.l_len = 0;
2206 lf.l_type = F_UNLCK;
2207 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader,
2208 F_UNLCK, &lf, F_POSIX);
2209 }
2210 fdtol = td->td_proc->p_fdtol;
2211 if (fdtol != NULL) {
2212 /*
2213 * Handle special case where file descriptor table is
2214 * shared between multiple process leaders.
2215 */
2216 fdp = td->td_proc->p_fd;
2217 FILEDESC_XLOCK(fdp);
2218 for (fdtol = fdtol->fdl_next;
2219 fdtol != td->td_proc->p_fdtol;
2220 fdtol = fdtol->fdl_next) {
2221 if ((fdtol->fdl_leader->p_flag &
2222 P_ADVLOCK) == 0)
2223 continue;
2224 fdtol->fdl_holdcount++;
2225 FILEDESC_XUNLOCK(fdp);
2226 lf.l_whence = SEEK_SET;
2227 lf.l_start = 0;
2228 lf.l_len = 0;
2229 lf.l_type = F_UNLCK;
2230 vp = fp_object->f_vnode;
2231 (void) VOP_ADVLOCK(vp,
2232 (caddr_t)fdtol->fdl_leader,
2233 F_UNLCK, &lf, F_POSIX);
2234 FILEDESC_XLOCK(fdp);
2235 fdtol->fdl_holdcount--;
2236 if (fdtol->fdl_holdcount == 0 &&
2237 fdtol->fdl_wakeup != 0) {
2238 fdtol->fdl_wakeup = 0;
2239 wakeup(fdtol);
2240 }
2241 }
2242 FILEDESC_XUNLOCK(fdp);
2243 }
2244 VFS_UNLOCK_GIANT(vfslocked);
2245 }
2246 return (fdrop(fp, td));
2247 }
2248
2249 /*
2250 * Initialize the file pointer with the specified properties.
2251 *
2252 * The ops are set with release semantics to be certain that the flags, type,
2253 * and data are visible when ops is. This is to prevent ops methods from being
2254 * called with bad data.
2255 */
2256 void
2257 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops)
2258 {
2259 fp->f_data = data;
2260 fp->f_flag = flag;
2261 fp->f_type = type;
2262 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops);
2263 }
2264
2265 struct file *
2266 fget_unlocked(struct filedesc *fdp, int fd)
2267 {
2268 struct file *fp;
2269 u_int count;
2270
2271 if (fd < 0 || fd >= fdp->fd_nfiles)
2272 return (NULL);
2273 /*
2274 * Fetch the descriptor locklessly. We avoid fdrop() races by
2275 * never raising a refcount above 0. To accomplish this we have
2276 * to use a cmpset loop rather than an atomic_add. The descriptor
2277 * must be re-verified once we acquire a reference to be certain
2278 * that the identity is still correct and we did not lose a race
2279 * due to preemption.
2280 */
2281 for (;;) {
2282 fp = fdp->fd_ofiles[fd];
2283 if (fp == NULL)
2284 break;
2285 count = fp->f_count;
2286 if (count == 0)
2287 continue;
2288 /*
2289 * Use an acquire barrier to prevent caching of fd_ofiles
2290 * so it is refreshed for verification.
2291 */
2292 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1)
2293 continue;
2294 if (fp == fdp->fd_ofiles[fd])
2295 break;
2296 fdrop(fp, curthread);
2297 }
2298
2299 return (fp);
2300 }
2301
2302 /*
2303 * Extract the file pointer associated with the specified descriptor for the
2304 * current user process.
2305 *
2306 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is
2307 * returned.
2308 *
2309 * If the FGET_GETCAP flag is set, the capability itself will be returned.
2310 * Calling _fget() with FGET_GETCAP on a non-capability will return EINVAL.
2311 * Otherwise, if the file is a capability, its rights will be checked against
2312 * the capability rights mask, and if successful, the object will be unwrapped.
2313 *
2314 * If an error occured the non-zero error is returned and *fpp is set to
2315 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is
2316 * responsible for fdrop().
2317 */
2318 #define FGET_GETCAP 0x00000001
2319 static __inline int
2320 _fget(struct thread *td, int fd, struct file **fpp, int flags,
2321 cap_rights_t needrights, cap_rights_t *haverightsp, u_char *maxprotp,
2322 int fget_flags)
2323 {
2324 struct filedesc *fdp;
2325 struct file *fp;
2326 #ifdef CAPABILITIES
2327 struct file *fp_fromcap;
2328 int error;
2329 #endif
2330
2331 *fpp = NULL;
2332 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL)
2333 return (EBADF);
2334 if ((fp = fget_unlocked(fdp, fd)) == NULL)
2335 return (EBADF);
2336 if (fp->f_ops == &badfileops) {
2337 fdrop(fp, td);
2338 return (EBADF);
2339 }
2340
2341 #ifdef CAPABILITIES
2342 /*
2343 * If this is a capability, what rights does it have?
2344 */
2345 if (haverightsp != NULL) {
2346 if (fp->f_type == DTYPE_CAPABILITY)
2347 *haverightsp = cap_rights(fp);
2348 else
2349 *haverightsp = CAP_MASK_VALID;
2350 }
2351
2352 /*
2353 * If a capability has been requested, return the capability directly.
2354 * Otherwise, check capability rights, extract the underlying object,
2355 * and check its access flags.
2356 */
2357 if (fget_flags & FGET_GETCAP) {
2358 if (fp->f_type != DTYPE_CAPABILITY) {
2359 fdrop(fp, td);
2360 return (EINVAL);
2361 }
2362 } else {
2363 if (maxprotp == NULL)
2364 error = cap_funwrap(fp, needrights, &fp_fromcap);
2365 else
2366 error = cap_funwrap_mmap(fp, needrights, maxprotp,
2367 &fp_fromcap);
2368 if (error) {
2369 fdrop(fp, td);
2370 return (error);
2371 }
2372
2373 /*
2374 * If we've unwrapped a file, drop the original capability
2375 * and hold the new descriptor. fp after this point refers to
2376 * the actual (unwrapped) object, not the capability.
2377 */
2378 if (fp != fp_fromcap) {
2379 fhold(fp_fromcap);
2380 fdrop(fp, td);
2381 fp = fp_fromcap;
2382 }
2383 }
2384 #else /* !CAPABILITIES */
2385 KASSERT(fp->f_type != DTYPE_CAPABILITY,
2386 ("%s: saw capability", __func__));
2387 if (maxprotp != NULL)
2388 *maxprotp = VM_PROT_ALL;
2389 #endif /* CAPABILITIES */
2390
2391 /*
2392 * FREAD and FWRITE failure return EBADF as per POSIX.
2393 *
2394 * Only one flag, or 0, may be specified.
2395 */
2396 if ((flags == FREAD && (fp->f_flag & FREAD) == 0) ||
2397 (flags == FWRITE && (fp->f_flag & FWRITE) == 0)) {
2398 fdrop(fp, td);
2399 return (EBADF);
2400 }
2401 *fpp = fp;
2402 return (0);
2403 }
2404
2405 int
2406 fget(struct thread *td, int fd, cap_rights_t rights, struct file **fpp)
2407 {
2408
2409 return(_fget(td, fd, fpp, 0, rights, NULL, NULL, 0));
2410 }
2411
2412 int
2413 fget_mmap(struct thread *td, int fd, cap_rights_t rights, u_char *maxprotp,
2414 struct file **fpp)
2415 {
2416
2417 return (_fget(td, fd, fpp, 0, rights, NULL, maxprotp, 0));
2418 }
2419
2420 int
2421 fget_read(struct thread *td, int fd, cap_rights_t rights, struct file **fpp)
2422 {
2423
2424 return(_fget(td, fd, fpp, FREAD, rights, NULL, NULL, 0));
2425 }
2426
2427 int
2428 fget_write(struct thread *td, int fd, cap_rights_t rights, struct file **fpp)
2429 {
2430
2431 return (_fget(td, fd, fpp, FWRITE, rights, NULL, NULL, 0));
2432 }
2433
2434 /*
2435 * Unlike the other fget() calls, which accept and check capability rights
2436 * but never return capabilities, fgetcap() returns the capability but doesn't
2437 * check capability rights.
2438 */
2439 int
2440 fgetcap(struct thread *td, int fd, struct file **fpp)
2441 {
2442
2443 return (_fget(td, fd, fpp, 0, 0, NULL, NULL, FGET_GETCAP));
2444 }
2445
2446
2447 /*
2448 * Like fget() but loads the underlying vnode, or returns an error if the
2449 * descriptor does not represent a vnode. Note that pipes use vnodes but
2450 * never have VM objects. The returned vnode will be vref()'d.
2451 *
2452 * XXX: what about the unused flags ?
2453 */
2454 static __inline int
2455 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t needrights,
2456 cap_rights_t *haverightsp, struct vnode **vpp)
2457 {
2458 struct file *fp;
2459 int error;
2460
2461 *vpp = NULL;
2462 if ((error = _fget(td, fd, &fp, flags, needrights, haverightsp,
2463 NULL, 0)) != 0)
2464 return (error);
2465 if (fp->f_vnode == NULL) {
2466 error = EINVAL;
2467 } else {
2468 *vpp = fp->f_vnode;
2469 vref(*vpp);
2470 }
2471 fdrop(fp, td);
2472
2473 return (error);
2474 }
2475
2476 int
2477 fgetvp(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp)
2478 {
2479
2480 return (_fgetvp(td, fd, 0, rights, NULL, vpp));
2481 }
2482
2483 int
2484 fgetvp_rights(struct thread *td, int fd, cap_rights_t need, cap_rights_t *have,
2485 struct vnode **vpp)
2486 {
2487 return (_fgetvp(td, fd, 0, need, have, vpp));
2488 }
2489
2490 int
2491 fgetvp_read(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp)
2492 {
2493
2494 return (_fgetvp(td, fd, FREAD, rights, NULL, vpp));
2495 }
2496
2497 #ifdef notyet
2498 int
2499 fgetvp_write(struct thread *td, int fd, cap_rights_t rights,
2500 struct vnode **vpp)
2501 {
2502
2503 return (_fgetvp(td, fd, FWRITE, rights, NULL, vpp));
2504 }
2505 #endif
2506
2507 /*
2508 * Like fget() but loads the underlying socket, or returns an error if the
2509 * descriptor does not represent a socket.
2510 *
2511 * We bump the ref count on the returned socket. XXX Also obtain the SX lock
2512 * in the future.
2513 *
2514 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely
2515 * on their file descriptor reference to prevent the socket from being free'd
2516 * during use.
2517 */
2518 int
2519 fgetsock(struct thread *td, int fd, cap_rights_t rights, struct socket **spp,
2520 u_int *fflagp)
2521 {
2522 struct file *fp;
2523 int error;
2524
2525 *spp = NULL;
2526 if (fflagp != NULL)
2527 *fflagp = 0;
2528 if ((error = _fget(td, fd, &fp, 0, rights, NULL, NULL, 0)) != 0)
2529 return (error);
2530 if (fp->f_type != DTYPE_SOCKET) {
2531 error = ENOTSOCK;
2532 } else {
2533 *spp = fp->f_data;
2534 if (fflagp)
2535 *fflagp = fp->f_flag;
2536 SOCK_LOCK(*spp);
2537 soref(*spp);
2538 SOCK_UNLOCK(*spp);
2539 }
2540 fdrop(fp, td);
2541
2542 return (error);
2543 }
2544
2545 /*
2546 * Drop the reference count on the socket and XXX release the SX lock in the
2547 * future. The last reference closes the socket.
2548 *
2549 * Note: fputsock() is deprecated, see comment for fgetsock().
2550 */
2551 void
2552 fputsock(struct socket *so)
2553 {
2554
2555 ACCEPT_LOCK();
2556 SOCK_LOCK(so);
2557 CURVNET_SET(so->so_vnet);
2558 sorele(so);
2559 CURVNET_RESTORE();
2560 }
2561
2562 /*
2563 * Handle the last reference to a file being closed.
2564 *
2565 * No special capability handling here, as the capability's fo_close will run
2566 * instead of the object here, and perform any necessary drop on the object.
2567 */
2568 int
2569 _fdrop(struct file *fp, struct thread *td)
2570 {
2571 int error;
2572
2573 error = 0;
2574 if (fp->f_count != 0)
2575 panic("fdrop: count %d", fp->f_count);
2576 if (fp->f_ops != &badfileops)
2577 error = fo_close(fp, td);
2578 /*
2579 * The f_cdevpriv cannot be assigned non-NULL value while we
2580 * are destroying the file.
2581 */
2582 if (fp->f_cdevpriv != NULL)
2583 devfs_fpdrop(fp);
2584 atomic_subtract_int(&openfiles, 1);
2585 crfree(fp->f_cred);
2586 uma_zfree(file_zone, fp);
2587
2588 return (error);
2589 }
2590
2591 /*
2592 * Apply an advisory lock on a file descriptor.
2593 *
2594 * Just attempt to get a record lock of the requested type on the entire file
2595 * (l_whence = SEEK_SET, l_start = 0, l_len = 0).
2596 */
2597 #ifndef _SYS_SYSPROTO_H_
2598 struct flock_args {
2599 int fd;
2600 int how;
2601 };
2602 #endif
2603 /* ARGSUSED */
2604 int
2605 sys_flock(struct thread *td, struct flock_args *uap)
2606 {
2607 struct file *fp;
2608 struct vnode *vp;
2609 struct flock lf;
2610 int vfslocked;
2611 int error;
2612
2613 if ((error = fget(td, uap->fd, CAP_FLOCK, &fp)) != 0)
2614 return (error);
2615 if (fp->f_type != DTYPE_VNODE) {
2616 fdrop(fp, td);
2617 return (EOPNOTSUPP);
2618 }
2619
2620 vp = fp->f_vnode;
2621 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
2622 lf.l_whence = SEEK_SET;
2623 lf.l_start = 0;
2624 lf.l_len = 0;
2625 if (uap->how & LOCK_UN) {
2626 lf.l_type = F_UNLCK;
2627 atomic_clear_int(&fp->f_flag, FHASLOCK);
2628 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK);
2629 goto done2;
2630 }
2631 if (uap->how & LOCK_EX)
2632 lf.l_type = F_WRLCK;
2633 else if (uap->how & LOCK_SH)
2634 lf.l_type = F_RDLCK;
2635 else {
2636 error = EBADF;
2637 goto done2;
2638 }
2639 atomic_set_int(&fp->f_flag, FHASLOCK);
2640 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
2641 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT);
2642 done2:
2643 fdrop(fp, td);
2644 VFS_UNLOCK_GIANT(vfslocked);
2645 return (error);
2646 }
2647 /*
2648 * Duplicate the specified descriptor to a free descriptor.
2649 */
2650 int
2651 dupfdopen(struct thread *td, struct filedesc *fdp, int indx, int dfd, int mode, int error)
2652 {
2653 struct file *wfp;
2654 struct file *fp;
2655
2656 /*
2657 * If the to-be-dup'd fd number is greater than the allowed number
2658 * of file descriptors, or the fd to be dup'd has already been
2659 * closed, then reject.
2660 */
2661 FILEDESC_XLOCK(fdp);
2662 if (dfd < 0 || dfd >= fdp->fd_nfiles ||
2663 (wfp = fdp->fd_ofiles[dfd]) == NULL) {
2664 FILEDESC_XUNLOCK(fdp);
2665 return (EBADF);
2666 }
2667
2668 /*
2669 * There are two cases of interest here.
2670 *
2671 * For ENODEV simply dup (dfd) to file descriptor (indx) and return.
2672 *
2673 * For ENXIO steal away the file structure from (dfd) and store it in
2674 * (indx). (dfd) is effectively closed by this operation.
2675 *
2676 * Any other error code is just returned.
2677 */
2678 switch (error) {
2679 case ENODEV:
2680 /*
2681 * Check that the mode the file is being opened for is a
2682 * subset of the mode of the existing descriptor.
2683 */
2684 if (((mode & (FREAD|FWRITE)) | wfp->f_flag) != wfp->f_flag) {
2685 FILEDESC_XUNLOCK(fdp);
2686 return (EACCES);
2687 }
2688 fp = fdp->fd_ofiles[indx];
2689 fdp->fd_ofiles[indx] = wfp;
2690 fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd];
2691 if (fp == NULL)
2692 fdused(fdp, indx);
2693 fhold(wfp);
2694 FILEDESC_XUNLOCK(fdp);
2695 if (fp != NULL)
2696 /*
2697 * We now own the reference to fp that the ofiles[]
2698 * array used to own. Release it.
2699 */
2700 fdrop(fp, td);
2701 return (0);
2702
2703 case ENXIO:
2704 /*
2705 * Steal away the file pointer from dfd and stuff it into indx.
2706 */
2707 fp = fdp->fd_ofiles[indx];
2708 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd];
2709 fdp->fd_ofiles[dfd] = NULL;
2710 fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd];
2711 fdp->fd_ofileflags[dfd] = 0;
2712 fdunused(fdp, dfd);
2713 if (fp == NULL)
2714 fdused(fdp, indx);
2715 FILEDESC_XUNLOCK(fdp);
2716
2717 /*
2718 * We now own the reference to fp that the ofiles[] array
2719 * used to own. Release it.
2720 */
2721 if (fp != NULL)
2722 fdrop(fp, td);
2723 return (0);
2724
2725 default:
2726 FILEDESC_XUNLOCK(fdp);
2727 return (error);
2728 }
2729 /* NOTREACHED */
2730 }
2731
2732 /*
2733 * Scan all active processes and prisons to see if any of them have a current
2734 * or root directory of `olddp'. If so, replace them with the new mount point.
2735 */
2736 void
2737 mountcheckdirs(struct vnode *olddp, struct vnode *newdp)
2738 {
2739 struct filedesc *fdp;
2740 struct prison *pr;
2741 struct proc *p;
2742 int nrele;
2743
2744 if (vrefcnt(olddp) == 1)
2745 return;
2746 nrele = 0;
2747 sx_slock(&allproc_lock);
2748 FOREACH_PROC_IN_SYSTEM(p) {
2749 fdp = fdhold(p);
2750 if (fdp == NULL)
2751 continue;
2752 FILEDESC_XLOCK(fdp);
2753 if (fdp->fd_cdir == olddp) {
2754 vref(newdp);
2755 fdp->fd_cdir = newdp;
2756 nrele++;
2757 }
2758 if (fdp->fd_rdir == olddp) {
2759 vref(newdp);
2760 fdp->fd_rdir = newdp;
2761 nrele++;
2762 }
2763 if (fdp->fd_jdir == olddp) {
2764 vref(newdp);
2765 fdp->fd_jdir = newdp;
2766 nrele++;
2767 }
2768 FILEDESC_XUNLOCK(fdp);
2769 fddrop(fdp);
2770 }
2771 sx_sunlock(&allproc_lock);
2772 if (rootvnode == olddp) {
2773 vref(newdp);
2774 rootvnode = newdp;
2775 nrele++;
2776 }
2777 mtx_lock(&prison0.pr_mtx);
2778 if (prison0.pr_root == olddp) {
2779 vref(newdp);
2780 prison0.pr_root = newdp;
2781 nrele++;
2782 }
2783 mtx_unlock(&prison0.pr_mtx);
2784 sx_slock(&allprison_lock);
2785 TAILQ_FOREACH(pr, &allprison, pr_list) {
2786 mtx_lock(&pr->pr_mtx);
2787 if (pr->pr_root == olddp) {
2788 vref(newdp);
2789 pr->pr_root = newdp;
2790 nrele++;
2791 }
2792 mtx_unlock(&pr->pr_mtx);
2793 }
2794 sx_sunlock(&allprison_lock);
2795 while (nrele--)
2796 vrele(olddp);
2797 }
2798
2799 struct filedesc_to_leader *
2800 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader)
2801 {
2802 struct filedesc_to_leader *fdtol;
2803
2804 fdtol = malloc(sizeof(struct filedesc_to_leader),
2805 M_FILEDESC_TO_LEADER,
2806 M_WAITOK);
2807 fdtol->fdl_refcount = 1;
2808 fdtol->fdl_holdcount = 0;
2809 fdtol->fdl_wakeup = 0;
2810 fdtol->fdl_leader = leader;
2811 if (old != NULL) {
2812 FILEDESC_XLOCK(fdp);
2813 fdtol->fdl_next = old->fdl_next;
2814 fdtol->fdl_prev = old;
2815 old->fdl_next = fdtol;
2816 fdtol->fdl_next->fdl_prev = fdtol;
2817 FILEDESC_XUNLOCK(fdp);
2818 } else {
2819 fdtol->fdl_next = fdtol;
2820 fdtol->fdl_prev = fdtol;
2821 }
2822 return (fdtol);
2823 }
2824
2825 /*
2826 * Get file structures globally.
2827 */
2828 static int
2829 sysctl_kern_file(SYSCTL_HANDLER_ARGS)
2830 {
2831 struct xfile xf;
2832 struct filedesc *fdp;
2833 struct file *fp;
2834 struct proc *p;
2835 int error, n;
2836
2837 error = sysctl_wire_old_buffer(req, 0);
2838 if (error != 0)
2839 return (error);
2840 if (req->oldptr == NULL) {
2841 n = 0;
2842 sx_slock(&allproc_lock);
2843 FOREACH_PROC_IN_SYSTEM(p) {
2844 if (p->p_state == PRS_NEW)
2845 continue;
2846 fdp = fdhold(p);
2847 if (fdp == NULL)
2848 continue;
2849 /* overestimates sparse tables. */
2850 if (fdp->fd_lastfile > 0)
2851 n += fdp->fd_lastfile;
2852 fddrop(fdp);
2853 }
2854 sx_sunlock(&allproc_lock);
2855 return (SYSCTL_OUT(req, 0, n * sizeof(xf)));
2856 }
2857 error = 0;
2858 bzero(&xf, sizeof(xf));
2859 xf.xf_size = sizeof(xf);
2860 sx_slock(&allproc_lock);
2861 FOREACH_PROC_IN_SYSTEM(p) {
2862 PROC_LOCK(p);
2863 if (p->p_state == PRS_NEW) {
2864 PROC_UNLOCK(p);
2865 continue;
2866 }
2867 if (p_cansee(req->td, p) != 0) {
2868 PROC_UNLOCK(p);
2869 continue;
2870 }
2871 xf.xf_pid = p->p_pid;
2872 xf.xf_uid = p->p_ucred->cr_uid;
2873 PROC_UNLOCK(p);
2874 fdp = fdhold(p);
2875 if (fdp == NULL)
2876 continue;
2877 FILEDESC_SLOCK(fdp);
2878 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) {
2879 if ((fp = fdp->fd_ofiles[n]) == NULL)
2880 continue;
2881 xf.xf_fd = n;
2882 xf.xf_file = fp;
2883 xf.xf_data = fp->f_data;
2884 xf.xf_vnode = fp->f_vnode;
2885 xf.xf_type = fp->f_type;
2886 xf.xf_count = fp->f_count;
2887 xf.xf_msgcount = 0;
2888 xf.xf_offset = fp->f_offset;
2889 xf.xf_flag = fp->f_flag;
2890 error = SYSCTL_OUT(req, &xf, sizeof(xf));
2891 if (error)
2892 break;
2893 }
2894 FILEDESC_SUNLOCK(fdp);
2895 fddrop(fdp);
2896 if (error)
2897 break;
2898 }
2899 sx_sunlock(&allproc_lock);
2900 return (error);
2901 }
2902
2903 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD,
2904 0, 0, sysctl_kern_file, "S,xfile", "Entire file table");
2905
2906 #ifdef KINFO_OFILE_SIZE
2907 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE);
2908 #endif
2909
2910 #ifdef COMPAT_FREEBSD7
2911 static int
2912 export_vnode_for_osysctl(struct vnode *vp, int type,
2913 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req)
2914 {
2915 int error;
2916 char *fullpath, *freepath;
2917 int vfslocked;
2918
2919 bzero(kif, sizeof(*kif));
2920 kif->kf_structsize = sizeof(*kif);
2921
2922 vref(vp);
2923 kif->kf_fd = type;
2924 kif->kf_type = KF_TYPE_VNODE;
2925 /* This function only handles directories. */
2926 if (vp->v_type != VDIR) {
2927 vrele(vp);
2928 return (ENOTDIR);
2929 }
2930 kif->kf_vnode_type = KF_VTYPE_VDIR;
2931
2932 /*
2933 * This is not a true file descriptor, so we set a bogus refcount
2934 * and offset to indicate these fields should be ignored.
2935 */
2936 kif->kf_ref_count = -1;
2937 kif->kf_offset = -1;
2938
2939 freepath = NULL;
2940 fullpath = "-";
2941 FILEDESC_SUNLOCK(fdp);
2942 vn_fullpath(curthread, vp, &fullpath, &freepath);
2943 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
2944 vrele(vp);
2945 VFS_UNLOCK_GIANT(vfslocked);
2946 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
2947 if (freepath != NULL)
2948 free(freepath, M_TEMP);
2949 error = SYSCTL_OUT(req, kif, sizeof(*kif));
2950 FILEDESC_SLOCK(fdp);
2951 return (error);
2952 }
2953
2954 /*
2955 * Get per-process file descriptors for use by procstat(1), et al.
2956 */
2957 static int
2958 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS)
2959 {
2960 char *fullpath, *freepath;
2961 struct kinfo_ofile *kif;
2962 struct filedesc *fdp;
2963 int error, i, *name;
2964 struct socket *so;
2965 struct vnode *vp;
2966 struct file *fp;
2967 struct proc *p;
2968 struct tty *tp;
2969 int vfslocked;
2970
2971 name = (int *)arg1;
2972 if ((p = pfind((pid_t)name[0])) == NULL)
2973 return (ESRCH);
2974 if ((error = p_candebug(curthread, p))) {
2975 PROC_UNLOCK(p);
2976 return (error);
2977 }
2978 fdp = fdhold(p);
2979 PROC_UNLOCK(p);
2980 if (fdp == NULL)
2981 return (ENOENT);
2982 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK);
2983 FILEDESC_SLOCK(fdp);
2984 if (fdp->fd_cdir != NULL)
2985 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif,
2986 fdp, req);
2987 if (fdp->fd_rdir != NULL)
2988 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif,
2989 fdp, req);
2990 if (fdp->fd_jdir != NULL)
2991 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif,
2992 fdp, req);
2993 for (i = 0; i < fdp->fd_nfiles; i++) {
2994 if ((fp = fdp->fd_ofiles[i]) == NULL)
2995 continue;
2996 bzero(kif, sizeof(*kif));
2997 kif->kf_structsize = sizeof(*kif);
2998 vp = NULL;
2999 so = NULL;
3000 tp = NULL;
3001 kif->kf_fd = i;
3002
3003 #ifdef CAPABILITIES
3004 /*
3005 * When reporting a capability, most fields will be from the
3006 * underlying object, but do mark as a capability. With
3007 * ofiledesc, we don't have a field to export the cap_rights_t,
3008 * but we do with the new filedesc.
3009 */
3010 if (fp->f_type == DTYPE_CAPABILITY) {
3011 kif->kf_flags |= KF_FLAG_CAPABILITY;
3012 (void)cap_funwrap(fp, 0, &fp);
3013 }
3014 #else
3015 KASSERT(fp->f_type != DTYPE_CAPABILITY,
3016 ("sysctl_kern_proc_ofiledesc: saw capability"));
3017 #endif
3018 switch (fp->f_type) {
3019 case DTYPE_VNODE:
3020 kif->kf_type = KF_TYPE_VNODE;
3021 vp = fp->f_vnode;
3022 break;
3023
3024 case DTYPE_SOCKET:
3025 kif->kf_type = KF_TYPE_SOCKET;
3026 so = fp->f_data;
3027 break;
3028
3029 case DTYPE_PIPE:
3030 kif->kf_type = KF_TYPE_PIPE;
3031 break;
3032
3033 case DTYPE_FIFO:
3034 kif->kf_type = KF_TYPE_FIFO;
3035 vp = fp->f_vnode;
3036 break;
3037
3038 case DTYPE_KQUEUE:
3039 kif->kf_type = KF_TYPE_KQUEUE;
3040 break;
3041
3042 case DTYPE_CRYPTO:
3043 kif->kf_type = KF_TYPE_CRYPTO;
3044 break;
3045
3046 case DTYPE_MQUEUE:
3047 kif->kf_type = KF_TYPE_MQUEUE;
3048 break;
3049
3050 case DTYPE_SHM:
3051 kif->kf_type = KF_TYPE_SHM;
3052 break;
3053
3054 case DTYPE_SEM:
3055 kif->kf_type = KF_TYPE_SEM;
3056 break;
3057
3058 case DTYPE_PTS:
3059 kif->kf_type = KF_TYPE_PTS;
3060 tp = fp->f_data;
3061 break;
3062
3063 #ifdef PROCDESC
3064 case DTYPE_PROCDESC:
3065 kif->kf_type = KF_TYPE_PROCDESC;
3066 break;
3067 #endif
3068
3069 default:
3070 kif->kf_type = KF_TYPE_UNKNOWN;
3071 break;
3072 }
3073 kif->kf_ref_count = fp->f_count;
3074 if (fp->f_flag & FREAD)
3075 kif->kf_flags |= KF_FLAG_READ;
3076 if (fp->f_flag & FWRITE)
3077 kif->kf_flags |= KF_FLAG_WRITE;
3078 if (fp->f_flag & FAPPEND)
3079 kif->kf_flags |= KF_FLAG_APPEND;
3080 if (fp->f_flag & FASYNC)
3081 kif->kf_flags |= KF_FLAG_ASYNC;
3082 if (fp->f_flag & FFSYNC)
3083 kif->kf_flags |= KF_FLAG_FSYNC;
3084 if (fp->f_flag & FNONBLOCK)
3085 kif->kf_flags |= KF_FLAG_NONBLOCK;
3086 if (fp->f_flag & O_DIRECT)
3087 kif->kf_flags |= KF_FLAG_DIRECT;
3088 if (fp->f_flag & FHASLOCK)
3089 kif->kf_flags |= KF_FLAG_HASLOCK;
3090 kif->kf_offset = fp->f_offset;
3091 if (vp != NULL) {
3092 vref(vp);
3093 switch (vp->v_type) {
3094 case VNON:
3095 kif->kf_vnode_type = KF_VTYPE_VNON;
3096 break;
3097 case VREG:
3098 kif->kf_vnode_type = KF_VTYPE_VREG;
3099 break;
3100 case VDIR:
3101 kif->kf_vnode_type = KF_VTYPE_VDIR;
3102 break;
3103 case VBLK:
3104 kif->kf_vnode_type = KF_VTYPE_VBLK;
3105 break;
3106 case VCHR:
3107 kif->kf_vnode_type = KF_VTYPE_VCHR;
3108 break;
3109 case VLNK:
3110 kif->kf_vnode_type = KF_VTYPE_VLNK;
3111 break;
3112 case VSOCK:
3113 kif->kf_vnode_type = KF_VTYPE_VSOCK;
3114 break;
3115 case VFIFO:
3116 kif->kf_vnode_type = KF_VTYPE_VFIFO;
3117 break;
3118 case VBAD:
3119 kif->kf_vnode_type = KF_VTYPE_VBAD;
3120 break;
3121 default:
3122 kif->kf_vnode_type = KF_VTYPE_UNKNOWN;
3123 break;
3124 }
3125 /*
3126 * It is OK to drop the filedesc lock here as we will
3127 * re-validate and re-evaluate its properties when
3128 * the loop continues.
3129 */
3130 freepath = NULL;
3131 fullpath = "-";
3132 FILEDESC_SUNLOCK(fdp);
3133 vn_fullpath(curthread, vp, &fullpath, &freepath);
3134 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3135 vrele(vp);
3136 VFS_UNLOCK_GIANT(vfslocked);
3137 strlcpy(kif->kf_path, fullpath,
3138 sizeof(kif->kf_path));
3139 if (freepath != NULL)
3140 free(freepath, M_TEMP);
3141 FILEDESC_SLOCK(fdp);
3142 }
3143 if (so != NULL) {
3144 struct sockaddr *sa;
3145
3146 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa)
3147 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) {
3148 bcopy(sa, &kif->kf_sa_local, sa->sa_len);
3149 free(sa, M_SONAME);
3150 }
3151 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa)
3152 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) {
3153 bcopy(sa, &kif->kf_sa_peer, sa->sa_len);
3154 free(sa, M_SONAME);
3155 }
3156 kif->kf_sock_domain =
3157 so->so_proto->pr_domain->dom_family;
3158 kif->kf_sock_type = so->so_type;
3159 kif->kf_sock_protocol = so->so_proto->pr_protocol;
3160 }
3161 if (tp != NULL) {
3162 strlcpy(kif->kf_path, tty_devname(tp),
3163 sizeof(kif->kf_path));
3164 }
3165 error = SYSCTL_OUT(req, kif, sizeof(*kif));
3166 if (error)
3167 break;
3168 }
3169 FILEDESC_SUNLOCK(fdp);
3170 fddrop(fdp);
3171 free(kif, M_TEMP);
3172 return (0);
3173 }
3174
3175 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD,
3176 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries");
3177 #endif /* COMPAT_FREEBSD7 */
3178
3179 #ifdef KINFO_FILE_SIZE
3180 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
3181 #endif
3182
3183 static int
3184 export_fd_for_sysctl(void *data, int type, int fd, int fflags, int refcnt,
3185 int64_t offset, int fd_is_cap, cap_rights_t fd_cap_rights,
3186 struct kinfo_file *kif, struct sysctl_req *req)
3187 {
3188 struct {
3189 int fflag;
3190 int kf_fflag;
3191 } fflags_table[] = {
3192 { FAPPEND, KF_FLAG_APPEND },
3193 { FASYNC, KF_FLAG_ASYNC },
3194 { FFSYNC, KF_FLAG_FSYNC },
3195 { FHASLOCK, KF_FLAG_HASLOCK },
3196 { FNONBLOCK, KF_FLAG_NONBLOCK },
3197 { FREAD, KF_FLAG_READ },
3198 { FWRITE, KF_FLAG_WRITE },
3199 { O_CREAT, KF_FLAG_CREAT },
3200 { O_DIRECT, KF_FLAG_DIRECT },
3201 { O_EXCL, KF_FLAG_EXCL },
3202 { O_EXEC, KF_FLAG_EXEC },
3203 { O_EXLOCK, KF_FLAG_EXLOCK },
3204 { O_NOFOLLOW, KF_FLAG_NOFOLLOW },
3205 { O_SHLOCK, KF_FLAG_SHLOCK },
3206 { O_TRUNC, KF_FLAG_TRUNC }
3207 };
3208 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table))
3209 struct vnode *vp;
3210 int error, vfslocked;
3211 unsigned int i;
3212
3213 bzero(kif, sizeof(*kif));
3214 switch (type) {
3215 case KF_TYPE_FIFO:
3216 case KF_TYPE_VNODE:
3217 vp = (struct vnode *)data;
3218 error = fill_vnode_info(vp, kif);
3219 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3220 vrele(vp);
3221 VFS_UNLOCK_GIANT(vfslocked);
3222 break;
3223 case KF_TYPE_SOCKET:
3224 error = fill_socket_info((struct socket *)data, kif);
3225 break;
3226 case KF_TYPE_PIPE:
3227 error = fill_pipe_info((struct pipe *)data, kif);
3228 break;
3229 case KF_TYPE_PTS:
3230 error = fill_pts_info((struct tty *)data, kif);
3231 break;
3232 case KF_TYPE_PROCDESC:
3233 error = fill_procdesc_info((struct procdesc *)data, kif);
3234 break;
3235 default:
3236 error = 0;
3237 }
3238 if (error == 0)
3239 kif->kf_status |= KF_ATTR_VALID;
3240
3241 /*
3242 * Translate file access flags.
3243 */
3244 for (i = 0; i < NFFLAGS; i++)
3245 if (fflags & fflags_table[i].fflag)
3246 kif->kf_flags |= fflags_table[i].kf_fflag;
3247 if (fd_is_cap)
3248 kif->kf_flags |= KF_FLAG_CAPABILITY;
3249 if (fd_is_cap)
3250 kif->kf_cap_rights = fd_cap_rights;
3251 kif->kf_fd = fd;
3252 kif->kf_type = type;
3253 kif->kf_ref_count = refcnt;
3254 kif->kf_offset = offset;
3255 /* Pack record size down */
3256 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) +
3257 strlen(kif->kf_path) + 1;
3258 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t));
3259 error = SYSCTL_OUT(req, kif, kif->kf_structsize);
3260 return (error);
3261 }
3262
3263 /*
3264 * Get per-process file descriptors for use by procstat(1), et al.
3265 */
3266 static int
3267 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS)
3268 {
3269 struct file *fp;
3270 struct filedesc *fdp;
3271 struct kinfo_file *kif;
3272 struct proc *p;
3273 struct vnode *cttyvp, *textvp, *tracevp;
3274 size_t oldidx;
3275 int64_t offset;
3276 void *data;
3277 int error, i, *name;
3278 int fd_is_cap, type, refcnt, fflags;
3279 cap_rights_t fd_cap_rights;
3280
3281 name = (int *)arg1;
3282 if ((p = pfind((pid_t)name[0])) == NULL)
3283 return (ESRCH);
3284 if ((error = p_candebug(curthread, p))) {
3285 PROC_UNLOCK(p);
3286 return (error);
3287 }
3288 /* ktrace vnode */
3289 tracevp = p->p_tracevp;
3290 if (tracevp != NULL)
3291 vref(tracevp);
3292 /* text vnode */
3293 textvp = p->p_textvp;
3294 if (textvp != NULL)
3295 vref(textvp);
3296 /* Controlling tty. */
3297 cttyvp = NULL;
3298 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) {
3299 cttyvp = p->p_pgrp->pg_session->s_ttyvp;
3300 if (cttyvp != NULL)
3301 vref(cttyvp);
3302 }
3303 fdp = fdhold(p);
3304 PROC_UNLOCK(p);
3305 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK);
3306 if (tracevp != NULL)
3307 export_fd_for_sysctl(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE,
3308 FREAD | FWRITE, -1, -1, 0, 0, kif, req);
3309 if (textvp != NULL)
3310 export_fd_for_sysctl(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT,
3311 FREAD, -1, -1, 0, 0, kif, req);
3312 if (cttyvp != NULL)
3313 export_fd_for_sysctl(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY,
3314 FREAD | FWRITE, -1, -1, 0, 0, kif, req);
3315 if (fdp == NULL)
3316 goto fail;
3317 FILEDESC_SLOCK(fdp);
3318 /* working directory */
3319 if (fdp->fd_cdir != NULL) {
3320 vref(fdp->fd_cdir);
3321 data = fdp->fd_cdir;
3322 FILEDESC_SUNLOCK(fdp);
3323 export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD,
3324 FREAD, -1, -1, 0, 0, kif, req);
3325 FILEDESC_SLOCK(fdp);
3326 }
3327 /* root directory */
3328 if (fdp->fd_rdir != NULL) {
3329 vref(fdp->fd_rdir);
3330 data = fdp->fd_rdir;
3331 FILEDESC_SUNLOCK(fdp);
3332 export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT,
3333 FREAD, -1, -1, 0, 0, kif, req);
3334 FILEDESC_SLOCK(fdp);
3335 }
3336 /* jail directory */
3337 if (fdp->fd_jdir != NULL) {
3338 vref(fdp->fd_jdir);
3339 data = fdp->fd_jdir;
3340 FILEDESC_SUNLOCK(fdp);
3341 export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL,
3342 FREAD, -1, -1, 0, 0, kif, req);
3343 FILEDESC_SLOCK(fdp);
3344 }
3345 for (i = 0; i < fdp->fd_nfiles; i++) {
3346 if ((fp = fdp->fd_ofiles[i]) == NULL)
3347 continue;
3348 data = NULL;
3349 fd_is_cap = 0;
3350 fd_cap_rights = 0;
3351
3352 #ifdef CAPABILITIES
3353 /*
3354 * When reporting a capability, most fields will be from the
3355 * underlying object, but do mark as a capability and export
3356 * the capability rights mask.
3357 */
3358 if (fp->f_type == DTYPE_CAPABILITY) {
3359 fd_is_cap = 1;
3360 fd_cap_rights = cap_rights(fp);
3361 (void)cap_funwrap(fp, 0, &fp);
3362 }
3363 #else /* !CAPABILITIES */
3364 KASSERT(fp->f_type != DTYPE_CAPABILITY,
3365 ("sysctl_kern_proc_filedesc: saw capability"));
3366 #endif
3367 switch (fp->f_type) {
3368 case DTYPE_VNODE:
3369 type = KF_TYPE_VNODE;
3370 vref(fp->f_vnode);
3371 data = fp->f_vnode;
3372 break;
3373
3374 case DTYPE_SOCKET:
3375 type = KF_TYPE_SOCKET;
3376 data = fp->f_data;
3377 break;
3378
3379 case DTYPE_PIPE:
3380 type = KF_TYPE_PIPE;
3381 data = fp->f_data;
3382 break;
3383
3384 case DTYPE_FIFO:
3385 type = KF_TYPE_FIFO;
3386 vref(fp->f_vnode);
3387 data = fp->f_vnode;
3388 break;
3389
3390 case DTYPE_KQUEUE:
3391 type = KF_TYPE_KQUEUE;
3392 break;
3393
3394 case DTYPE_CRYPTO:
3395 type = KF_TYPE_CRYPTO;
3396 break;
3397
3398 case DTYPE_MQUEUE:
3399 type = KF_TYPE_MQUEUE;
3400 break;
3401
3402 case DTYPE_SHM:
3403 type = KF_TYPE_SHM;
3404 break;
3405
3406 case DTYPE_SEM:
3407 type = KF_TYPE_SEM;
3408 break;
3409
3410 case DTYPE_PTS:
3411 type = KF_TYPE_PTS;
3412 data = fp->f_data;
3413 break;
3414
3415 #ifdef PROCDESC
3416 case DTYPE_PROCDESC:
3417 type = KF_TYPE_PROCDESC;
3418 data = fp->f_data;
3419 break;
3420 #endif
3421
3422 default:
3423 type = KF_TYPE_UNKNOWN;
3424 break;
3425 }
3426 refcnt = fp->f_count;
3427 fflags = fp->f_flag;
3428 offset = fp->f_offset;
3429
3430 /*
3431 * Create sysctl entry.
3432 * It is OK to drop the filedesc lock here as we will
3433 * re-validate and re-evaluate its properties when
3434 * the loop continues.
3435 */
3436 oldidx = req->oldidx;
3437 if (type == KF_TYPE_VNODE || type == KF_TYPE_FIFO)
3438 FILEDESC_SUNLOCK(fdp);
3439 error = export_fd_for_sysctl(data, type, i, fflags, refcnt,
3440 offset, fd_is_cap, fd_cap_rights, kif, req);
3441 if (type == KF_TYPE_VNODE || type == KF_TYPE_FIFO)
3442 FILEDESC_SLOCK(fdp);
3443 if (error) {
3444 if (error == ENOMEM) {
3445 /*
3446 * The hack to keep the ABI of sysctl
3447 * kern.proc.filedesc intact, but not
3448 * to account a partially copied
3449 * kinfo_file into the oldidx.
3450 */
3451 req->oldidx = oldidx;
3452 error = 0;
3453 }
3454 break;
3455 }
3456 }
3457 FILEDESC_SUNLOCK(fdp);
3458 fail:
3459 if (fdp != NULL)
3460 fddrop(fdp);
3461 free(kif, M_TEMP);
3462 return (error);
3463 }
3464
3465 int
3466 vntype_to_kinfo(int vtype)
3467 {
3468 struct {
3469 int vtype;
3470 int kf_vtype;
3471 } vtypes_table[] = {
3472 { VBAD, KF_VTYPE_VBAD },
3473 { VBLK, KF_VTYPE_VBLK },
3474 { VCHR, KF_VTYPE_VCHR },
3475 { VDIR, KF_VTYPE_VDIR },
3476 { VFIFO, KF_VTYPE_VFIFO },
3477 { VLNK, KF_VTYPE_VLNK },
3478 { VNON, KF_VTYPE_VNON },
3479 { VREG, KF_VTYPE_VREG },
3480 { VSOCK, KF_VTYPE_VSOCK }
3481 };
3482 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table))
3483 unsigned int i;
3484
3485 /*
3486 * Perform vtype translation.
3487 */
3488 for (i = 0; i < NVTYPES; i++)
3489 if (vtypes_table[i].vtype == vtype)
3490 break;
3491 if (i < NVTYPES)
3492 return (vtypes_table[i].kf_vtype);
3493
3494 return (KF_VTYPE_UNKNOWN);
3495 }
3496
3497 static int
3498 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif)
3499 {
3500 struct vattr va;
3501 char *fullpath, *freepath;
3502 int error, vfslocked;
3503
3504 if (vp == NULL)
3505 return (1);
3506 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type);
3507 freepath = NULL;
3508 fullpath = "-";
3509 error = vn_fullpath(curthread, vp, &fullpath, &freepath);
3510 if (error == 0) {
3511 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
3512 }
3513 if (freepath != NULL)
3514 free(freepath, M_TEMP);
3515
3516 /*
3517 * Retrieve vnode attributes.
3518 */
3519 va.va_fsid = VNOVAL;
3520 va.va_rdev = NODEV;
3521 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3522 vn_lock(vp, LK_SHARED | LK_RETRY);
3523 error = VOP_GETATTR(vp, &va, curthread->td_ucred);
3524 VOP_UNLOCK(vp, 0);
3525 VFS_UNLOCK_GIANT(vfslocked);
3526 if (error != 0)
3527 return (error);
3528 if (va.va_fsid != VNOVAL)
3529 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid;
3530 else
3531 kif->kf_un.kf_file.kf_file_fsid =
3532 vp->v_mount->mnt_stat.f_fsid.val[0];
3533 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid;
3534 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode);
3535 kif->kf_un.kf_file.kf_file_size = va.va_size;
3536 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev;
3537 return (0);
3538 }
3539
3540 static int
3541 fill_socket_info(struct socket *so, struct kinfo_file *kif)
3542 {
3543 struct sockaddr *sa;
3544 struct inpcb *inpcb;
3545 struct unpcb *unpcb;
3546 int error;
3547
3548 if (so == NULL)
3549 return (1);
3550 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family;
3551 kif->kf_sock_type = so->so_type;
3552 kif->kf_sock_protocol = so->so_proto->pr_protocol;
3553 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb;
3554 switch(kif->kf_sock_domain) {
3555 case AF_INET:
3556 case AF_INET6:
3557 if (kif->kf_sock_protocol == IPPROTO_TCP) {
3558 if (so->so_pcb != NULL) {
3559 inpcb = (struct inpcb *)(so->so_pcb);
3560 kif->kf_un.kf_sock.kf_sock_inpcb =
3561 (uintptr_t)inpcb->inp_ppcb;
3562 }
3563 }
3564 break;
3565 case AF_UNIX:
3566 if (so->so_pcb != NULL) {
3567 unpcb = (struct unpcb *)(so->so_pcb);
3568 if (unpcb->unp_conn) {
3569 kif->kf_un.kf_sock.kf_sock_unpconn =
3570 (uintptr_t)unpcb->unp_conn;
3571 kif->kf_un.kf_sock.kf_sock_rcv_sb_state =
3572 so->so_rcv.sb_state;
3573 kif->kf_un.kf_sock.kf_sock_snd_sb_state =
3574 so->so_snd.sb_state;
3575 }
3576 }
3577 break;
3578 }
3579 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
3580 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) {
3581 bcopy(sa, &kif->kf_sa_local, sa->sa_len);
3582 free(sa, M_SONAME);
3583 }
3584 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa);
3585 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) {
3586 bcopy(sa, &kif->kf_sa_peer, sa->sa_len);
3587 free(sa, M_SONAME);
3588 }
3589 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name,
3590 sizeof(kif->kf_path));
3591 return (0);
3592 }
3593
3594 static int
3595 fill_pts_info(struct tty *tp, struct kinfo_file *kif)
3596 {
3597
3598 if (tp == NULL)
3599 return (1);
3600 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp);
3601 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path));
3602 return (0);
3603 }
3604
3605 static int
3606 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif)
3607 {
3608
3609 if (pi == NULL)
3610 return (1);
3611 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi;
3612 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer;
3613 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt;
3614 return (0);
3615 }
3616
3617 static int
3618 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif)
3619 {
3620
3621 if (pdp == NULL)
3622 return (1);
3623 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid;
3624 return (0);
3625 }
3626
3627 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD,
3628 sysctl_kern_proc_filedesc, "Process filedesc entries");
3629
3630 #ifdef DDB
3631 /*
3632 * For the purposes of debugging, generate a human-readable string for the
3633 * file type.
3634 */
3635 static const char *
3636 file_type_to_name(short type)
3637 {
3638
3639 switch (type) {
3640 case 0:
3641 return ("zero");
3642 case DTYPE_VNODE:
3643 return ("vnod");
3644 case DTYPE_SOCKET:
3645 return ("sock");
3646 case DTYPE_PIPE:
3647 return ("pipe");
3648 case DTYPE_FIFO:
3649 return ("fifo");
3650 case DTYPE_KQUEUE:
3651 return ("kque");
3652 case DTYPE_CRYPTO:
3653 return ("crpt");
3654 case DTYPE_MQUEUE:
3655 return ("mque");
3656 case DTYPE_SHM:
3657 return ("shm");
3658 case DTYPE_SEM:
3659 return ("ksem");
3660 default:
3661 return ("unkn");
3662 }
3663 }
3664
3665 /*
3666 * For the purposes of debugging, identify a process (if any, perhaps one of
3667 * many) that references the passed file in its file descriptor array. Return
3668 * NULL if none.
3669 */
3670 static struct proc *
3671 file_to_first_proc(struct file *fp)
3672 {
3673 struct filedesc *fdp;
3674 struct proc *p;
3675 int n;
3676
3677 FOREACH_PROC_IN_SYSTEM(p) {
3678 if (p->p_state == PRS_NEW)
3679 continue;
3680 fdp = p->p_fd;
3681 if (fdp == NULL)
3682 continue;
3683 for (n = 0; n < fdp->fd_nfiles; n++) {
3684 if (fp == fdp->fd_ofiles[n])
3685 return (p);
3686 }
3687 }
3688 return (NULL);
3689 }
3690
3691 static void
3692 db_print_file(struct file *fp, int header)
3693 {
3694 struct proc *p;
3695
3696 if (header)
3697 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n",
3698 "File", "Type", "Data", "Flag", "GCFl", "Count",
3699 "MCount", "Vnode", "FPID", "FCmd");
3700 p = file_to_first_proc(fp);
3701 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp,
3702 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag,
3703 0, fp->f_count, 0, fp->f_vnode,
3704 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-");
3705 }
3706
3707 DB_SHOW_COMMAND(file, db_show_file)
3708 {
3709 struct file *fp;
3710
3711 if (!have_addr) {
3712 db_printf("usage: show file <addr>\n");
3713 return;
3714 }
3715 fp = (struct file *)addr;
3716 db_print_file(fp, 1);
3717 }
3718
3719 DB_SHOW_COMMAND(files, db_show_files)
3720 {
3721 struct filedesc *fdp;
3722 struct file *fp;
3723 struct proc *p;
3724 int header;
3725 int n;
3726
3727 header = 1;
3728 FOREACH_PROC_IN_SYSTEM(p) {
3729 if (p->p_state == PRS_NEW)
3730 continue;
3731 if ((fdp = p->p_fd) == NULL)
3732 continue;
3733 for (n = 0; n < fdp->fd_nfiles; ++n) {
3734 if ((fp = fdp->fd_ofiles[n]) == NULL)
3735 continue;
3736 db_print_file(fp, header);
3737 header = 0;
3738 }
3739 }
3740 }
3741 #endif
3742
3743 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW,
3744 &maxfilesperproc, 0, "Maximum files allowed open per process");
3745
3746 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW,
3747 &maxfiles, 0, "Maximum number of files");
3748
3749 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD,
3750 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files");
3751
3752 /* ARGSUSED*/
3753 static void
3754 filelistinit(void *dummy)
3755 {
3756
3757 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL,
3758 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
3759 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF);
3760 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF);
3761 }
3762 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL);
3763
3764 /*-------------------------------------------------------------------*/
3765
3766 static int
3767 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags, struct thread *td)
3768 {
3769
3770 return (EBADF);
3771 }
3772
3773 static int
3774 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, struct thread *td)
3775 {
3776
3777 return (EINVAL);
3778 }
3779
3780 static int
3781 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, struct thread *td)
3782 {
3783
3784 return (EBADF);
3785 }
3786
3787 static int
3788 badfo_poll(struct file *fp, int events, struct ucred *active_cred, struct thread *td)
3789 {
3790
3791 return (0);
3792 }
3793
3794 static int
3795 badfo_kqfilter(struct file *fp, struct knote *kn)
3796 {
3797
3798 return (EBADF);
3799 }
3800
3801 static int
3802 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, struct thread *td)
3803 {
3804
3805 return (EBADF);
3806 }
3807
3808 static int
3809 badfo_close(struct file *fp, struct thread *td)
3810 {
3811
3812 return (EBADF);
3813 }
3814
3815 static int
3816 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
3817 struct thread *td)
3818 {
3819
3820 return (EBADF);
3821 }
3822
3823 static int
3824 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
3825 struct thread *td)
3826 {
3827
3828 return (EBADF);
3829 }
3830
3831 struct fileops badfileops = {
3832 .fo_read = badfo_readwrite,
3833 .fo_write = badfo_readwrite,
3834 .fo_truncate = badfo_truncate,
3835 .fo_ioctl = badfo_ioctl,
3836 .fo_poll = badfo_poll,
3837 .fo_kqfilter = badfo_kqfilter,
3838 .fo_stat = badfo_stat,
3839 .fo_close = badfo_close,
3840 .fo_chmod = badfo_chmod,
3841 .fo_chown = badfo_chown,
3842 };
3843
3844 int
3845 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
3846 struct thread *td)
3847 {
3848
3849 return (EINVAL);
3850 }
3851
3852 int
3853 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
3854 struct thread *td)
3855 {
3856
3857 return (EINVAL);
3858 }
3859
3860 /*-------------------------------------------------------------------*/
3861
3862 /*
3863 * File Descriptor pseudo-device driver (/dev/fd/).
3864 *
3865 * Opening minor device N dup()s the file (if any) connected to file
3866 * descriptor N belonging to the calling process. Note that this driver
3867 * consists of only the ``open()'' routine, because all subsequent
3868 * references to this file will be direct to the other driver.
3869 *
3870 * XXX: we could give this one a cloning event handler if necessary.
3871 */
3872
3873 /* ARGSUSED */
3874 static int
3875 fdopen(struct cdev *dev, int mode, int type, struct thread *td)
3876 {
3877
3878 /*
3879 * XXX Kludge: set curthread->td_dupfd to contain the value of the
3880 * the file descriptor being sought for duplication. The error
3881 * return ensures that the vnode for this device will be released
3882 * by vn_open. Open will detect this special error and take the
3883 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN
3884 * will simply report the error.
3885 */
3886 td->td_dupfd = dev2unit(dev);
3887 return (ENODEV);
3888 }
3889
3890 static struct cdevsw fildesc_cdevsw = {
3891 .d_version = D_VERSION,
3892 .d_open = fdopen,
3893 .d_name = "FD",
3894 };
3895
3896 static void
3897 fildesc_drvinit(void *unused)
3898 {
3899 struct cdev *dev;
3900
3901 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL,
3902 UID_ROOT, GID_WHEEL, 0666, "fd/0");
3903 make_dev_alias(dev, "stdin");
3904 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL,
3905 UID_ROOT, GID_WHEEL, 0666, "fd/1");
3906 make_dev_alias(dev, "stdout");
3907 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL,
3908 UID_ROOT, GID_WHEEL, 0666, "fd/2");
3909 make_dev_alias(dev, "stderr");
3910 }
3911
3912 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL);
Cache object: d084beb6815fd765977b77c1d99fab9c
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