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("$FreeBSD$");
39
40 #include "opt_capsicum.h"
41 #include "opt_compat.h"
42 #include "opt_ddb.h"
43 #include "opt_ktrace.h"
44 #include "opt_procdesc.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48
49 #include <sys/capability.h>
50 #include <sys/conf.h>
51 #include <sys/domain.h>
52 #include <sys/fcntl.h>
53 #include <sys/file.h>
54 #include <sys/filedesc.h>
55 #include <sys/filio.h>
56 #include <sys/jail.h>
57 #include <sys/kernel.h>
58 #include <sys/ksem.h>
59 #include <sys/limits.h>
60 #include <sys/lock.h>
61 #include <sys/malloc.h>
62 #include <sys/mman.h>
63 #include <sys/mount.h>
64 #include <sys/mqueue.h>
65 #include <sys/mutex.h>
66 #include <sys/namei.h>
67 #include <sys/selinfo.h>
68 #include <sys/pipe.h>
69 #include <sys/priv.h>
70 #include <sys/proc.h>
71 #include <sys/procdesc.h>
72 #include <sys/protosw.h>
73 #include <sys/racct.h>
74 #include <sys/resourcevar.h>
75 #include <sys/sbuf.h>
76 #include <sys/signalvar.h>
77 #include <sys/socketvar.h>
78 #include <sys/stat.h>
79 #include <sys/sx.h>
80 #include <sys/syscallsubr.h>
81 #include <sys/sysctl.h>
82 #include <sys/sysproto.h>
83 #include <sys/tty.h>
84 #include <sys/unistd.h>
85 #include <sys/un.h>
86 #include <sys/unpcb.h>
87 #include <sys/user.h>
88 #include <sys/vnode.h>
89 #ifdef KTRACE
90 #include <sys/ktrace.h>
91 #endif
92
93 #include <net/vnet.h>
94
95 #include <netinet/in.h>
96 #include <netinet/in_pcb.h>
97
98 #include <security/audit/audit.h>
99
100 #include <vm/uma.h>
101 #include <vm/vm.h>
102
103 #include <ddb/ddb.h>
104
105 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table");
106 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader",
107 "file desc to leader structures");
108 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures");
109
110 MALLOC_DECLARE(M_FADVISE);
111
112 static uma_zone_t file_zone;
113
114 void (*ksem_info)(struct ksem *ks, char *path, size_t size, uint32_t *value);
115
116 /* Flags for do_dup() */
117 #define DUP_FIXED 0x1 /* Force fixed allocation */
118 #define DUP_FCNTL 0x2 /* fcntl()-style errors */
119 #define DUP_CLOEXEC 0x4 /* Atomically set FD_CLOEXEC. */
120
121 static int do_dup(struct thread *td, int flags, int old, int new,
122 register_t *retval);
123 static int fd_first_free(struct filedesc *, int, int);
124 static int fd_last_used(struct filedesc *, int, int);
125 static void fdgrowtable(struct filedesc *, int);
126 static void fdunused(struct filedesc *fdp, int fd);
127 static void fdused(struct filedesc *fdp, int fd);
128 static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif);
129 static int fill_socket_info(struct socket *so, struct kinfo_file *kif);
130 static int fill_pts_info(struct tty *tp, struct kinfo_file *kif);
131 static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif);
132 static int fill_procdesc_info(struct procdesc *pdp,
133 struct kinfo_file *kif);
134 static int fill_sem_info(struct file *fp, struct kinfo_file *kif);
135 static int fill_shm_info(struct file *fp, struct kinfo_file *kif);
136 static int getmaxfd(struct proc *p);
137
138 /*
139 * A process is initially started out with NDFILE descriptors stored within
140 * this structure, selected to be enough for typical applications based on
141 * the historical limit of 20 open files (and the usage of descriptors by
142 * shells). If these descriptors are exhausted, a larger descriptor table
143 * may be allocated, up to a process' resource limit; the internal arrays
144 * are then unused.
145 */
146 #define NDFILE 20
147 #define NDSLOTSIZE sizeof(NDSLOTTYPE)
148 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT)
149 #define NDSLOT(x) ((x) / NDENTRIES)
150 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES))
151 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES)
152
153 /*
154 * Storage required per open file descriptor.
155 */
156 #define OFILESIZE (sizeof(struct file *) + sizeof(char))
157
158 /*
159 * Storage to hold unused ofiles that need to be reclaimed.
160 */
161 struct freetable {
162 struct file **ft_table;
163 SLIST_ENTRY(freetable) ft_next;
164 };
165
166 /*
167 * Basic allocation of descriptors:
168 * one of the above, plus arrays for NDFILE descriptors.
169 */
170 struct filedesc0 {
171 struct filedesc fd_fd;
172 /*
173 * ofiles which need to be reclaimed on free.
174 */
175 SLIST_HEAD(,freetable) fd_free;
176 /*
177 * These arrays are used when the number of open files is
178 * <= NDFILE, and are then pointed to by the pointers above.
179 */
180 struct file *fd_dfiles[NDFILE];
181 char fd_dfileflags[NDFILE];
182 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)];
183 };
184
185 /*
186 * Descriptor management.
187 */
188 volatile int openfiles; /* actual number of open files */
189 struct mtx sigio_lock; /* mtx to protect pointers to sigio */
190 void (*mq_fdclose)(struct thread *td, int fd, struct file *fp);
191
192 /* A mutex to protect the association between a proc and filedesc. */
193 static struct mtx fdesc_mtx;
194
195 /*
196 * Find the first zero bit in the given bitmap, starting at low and not
197 * exceeding size - 1.
198 */
199 static int
200 fd_first_free(struct filedesc *fdp, int low, int size)
201 {
202 NDSLOTTYPE *map = fdp->fd_map;
203 NDSLOTTYPE mask;
204 int off, maxoff;
205
206 if (low >= size)
207 return (low);
208
209 off = NDSLOT(low);
210 if (low % NDENTRIES) {
211 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES)));
212 if ((mask &= ~map[off]) != 0UL)
213 return (off * NDENTRIES + ffsl(mask) - 1);
214 ++off;
215 }
216 for (maxoff = NDSLOTS(size); off < maxoff; ++off)
217 if (map[off] != ~0UL)
218 return (off * NDENTRIES + ffsl(~map[off]) - 1);
219 return (size);
220 }
221
222 /*
223 * Find the highest non-zero bit in the given bitmap, starting at low and
224 * not exceeding size - 1.
225 */
226 static int
227 fd_last_used(struct filedesc *fdp, int low, int size)
228 {
229 NDSLOTTYPE *map = fdp->fd_map;
230 NDSLOTTYPE mask;
231 int off, minoff;
232
233 if (low >= size)
234 return (-1);
235
236 off = NDSLOT(size);
237 if (size % NDENTRIES) {
238 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES));
239 if ((mask &= map[off]) != 0)
240 return (off * NDENTRIES + flsl(mask) - 1);
241 --off;
242 }
243 for (minoff = NDSLOT(low); off >= minoff; --off)
244 if (map[off] != 0)
245 return (off * NDENTRIES + flsl(map[off]) - 1);
246 return (low - 1);
247 }
248
249 static int
250 fdisused(struct filedesc *fdp, int fd)
251 {
252 KASSERT(fd >= 0 && fd < fdp->fd_nfiles,
253 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles));
254 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0);
255 }
256
257 /*
258 * Mark a file descriptor as used.
259 */
260 static void
261 fdused(struct filedesc *fdp, int fd)
262 {
263
264 FILEDESC_XLOCK_ASSERT(fdp);
265 KASSERT(!fdisused(fdp, fd),
266 ("fd already used"));
267
268 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd);
269 if (fd > fdp->fd_lastfile)
270 fdp->fd_lastfile = fd;
271 if (fd == fdp->fd_freefile)
272 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles);
273 }
274
275 /*
276 * Mark a file descriptor as unused.
277 */
278 static void
279 fdunused(struct filedesc *fdp, int fd)
280 {
281
282 FILEDESC_XLOCK_ASSERT(fdp);
283 KASSERT(fdisused(fdp, fd),
284 ("fd is already unused"));
285 KASSERT(fdp->fd_ofiles[fd] == NULL,
286 ("fd is still in use"));
287
288 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd);
289 if (fd < fdp->fd_freefile)
290 fdp->fd_freefile = fd;
291 if (fd == fdp->fd_lastfile)
292 fdp->fd_lastfile = fd_last_used(fdp, 0, fd);
293 }
294
295 /*
296 * System calls on descriptors.
297 */
298 #ifndef _SYS_SYSPROTO_H_
299 struct getdtablesize_args {
300 int dummy;
301 };
302 #endif
303 /* ARGSUSED */
304 int
305 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap)
306 {
307 struct proc *p = td->td_proc;
308 uint64_t lim;
309
310 PROC_LOCK(p);
311 td->td_retval[0] =
312 min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc);
313 lim = racct_get_limit(td->td_proc, RACCT_NOFILE);
314 PROC_UNLOCK(p);
315 if (lim < td->td_retval[0])
316 td->td_retval[0] = lim;
317 return (0);
318 }
319
320 /*
321 * Duplicate a file descriptor to a particular value.
322 *
323 * Note: keep in mind that a potential race condition exists when closing
324 * descriptors from a shared descriptor table (via rfork).
325 */
326 #ifndef _SYS_SYSPROTO_H_
327 struct dup2_args {
328 u_int from;
329 u_int to;
330 };
331 #endif
332 /* ARGSUSED */
333 int
334 sys_dup2(struct thread *td, struct dup2_args *uap)
335 {
336
337 return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to,
338 td->td_retval));
339 }
340
341 /*
342 * Duplicate a file descriptor.
343 */
344 #ifndef _SYS_SYSPROTO_H_
345 struct dup_args {
346 u_int fd;
347 };
348 #endif
349 /* ARGSUSED */
350 int
351 sys_dup(struct thread *td, struct dup_args *uap)
352 {
353
354 return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval));
355 }
356
357 /*
358 * The file control system call.
359 */
360 #ifndef _SYS_SYSPROTO_H_
361 struct fcntl_args {
362 int fd;
363 int cmd;
364 long arg;
365 };
366 #endif
367 /* ARGSUSED */
368 int
369 sys_fcntl(struct thread *td, struct fcntl_args *uap)
370 {
371 struct flock fl;
372 struct __oflock ofl;
373 intptr_t arg;
374 int error;
375 int cmd;
376
377 error = 0;
378 cmd = uap->cmd;
379 switch (uap->cmd) {
380 case F_OGETLK:
381 case F_OSETLK:
382 case F_OSETLKW:
383 /*
384 * Convert old flock structure to new.
385 */
386 error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl));
387 fl.l_start = ofl.l_start;
388 fl.l_len = ofl.l_len;
389 fl.l_pid = ofl.l_pid;
390 fl.l_type = ofl.l_type;
391 fl.l_whence = ofl.l_whence;
392 fl.l_sysid = 0;
393
394 switch (uap->cmd) {
395 case F_OGETLK:
396 cmd = F_GETLK;
397 break;
398 case F_OSETLK:
399 cmd = F_SETLK;
400 break;
401 case F_OSETLKW:
402 cmd = F_SETLKW;
403 break;
404 }
405 arg = (intptr_t)&fl;
406 break;
407 case F_GETLK:
408 case F_SETLK:
409 case F_SETLKW:
410 case F_SETLK_REMOTE:
411 error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl));
412 arg = (intptr_t)&fl;
413 break;
414 default:
415 arg = uap->arg;
416 break;
417 }
418 if (error)
419 return (error);
420 error = kern_fcntl(td, uap->fd, cmd, arg);
421 if (error)
422 return (error);
423 if (uap->cmd == F_OGETLK) {
424 ofl.l_start = fl.l_start;
425 ofl.l_len = fl.l_len;
426 ofl.l_pid = fl.l_pid;
427 ofl.l_type = fl.l_type;
428 ofl.l_whence = fl.l_whence;
429 error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl));
430 } else if (uap->cmd == F_GETLK) {
431 error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl));
432 }
433 return (error);
434 }
435
436 static inline struct file *
437 fdtofp(int fd, struct filedesc *fdp)
438 {
439 struct file *fp;
440
441 FILEDESC_LOCK_ASSERT(fdp);
442 if ((unsigned)fd >= fdp->fd_nfiles ||
443 (fp = fdp->fd_ofiles[fd]) == NULL)
444 return (NULL);
445 return (fp);
446 }
447
448 static inline int
449 fdunwrap(int fd, cap_rights_t rights, struct filedesc *fdp, struct file **fpp)
450 {
451
452 *fpp = fdtofp(fd, fdp);
453 if (*fpp == NULL)
454 return (EBADF);
455
456 #ifdef CAPABILITIES
457 if ((*fpp)->f_type == DTYPE_CAPABILITY) {
458 int err = cap_funwrap(*fpp, rights, fpp);
459 if (err != 0) {
460 *fpp = NULL;
461 return (err);
462 }
463 }
464 #endif /* CAPABILITIES */
465 return (0);
466 }
467
468 int
469 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg)
470 {
471 struct filedesc *fdp;
472 struct flock *flp;
473 struct file *fp;
474 struct proc *p;
475 char *pop;
476 struct vnode *vp;
477 int error, flg, tmp;
478 int vfslocked;
479 u_int old, new;
480 uint64_t bsize;
481 off_t foffset;
482
483 vfslocked = 0;
484 error = 0;
485 flg = F_POSIX;
486 p = td->td_proc;
487 fdp = p->p_fd;
488
489 switch (cmd) {
490 case F_DUPFD:
491 tmp = arg;
492 error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval);
493 break;
494
495 case F_DUPFD_CLOEXEC:
496 tmp = arg;
497 error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp,
498 td->td_retval);
499 break;
500
501 case F_DUP2FD:
502 tmp = arg;
503 error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval);
504 break;
505
506 case F_DUP2FD_CLOEXEC:
507 tmp = arg;
508 error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp,
509 td->td_retval);
510 break;
511
512 case F_GETFD:
513 FILEDESC_SLOCK(fdp);
514 if ((fp = fdtofp(fd, fdp)) == NULL) {
515 FILEDESC_SUNLOCK(fdp);
516 error = EBADF;
517 break;
518 }
519 pop = &fdp->fd_ofileflags[fd];
520 td->td_retval[0] = (*pop & UF_EXCLOSE) ? FD_CLOEXEC : 0;
521 FILEDESC_SUNLOCK(fdp);
522 break;
523
524 case F_SETFD:
525 FILEDESC_XLOCK(fdp);
526 if ((fp = fdtofp(fd, fdp)) == NULL) {
527 FILEDESC_XUNLOCK(fdp);
528 error = EBADF;
529 break;
530 }
531 pop = &fdp->fd_ofileflags[fd];
532 *pop = (*pop &~ UF_EXCLOSE) |
533 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0);
534 FILEDESC_XUNLOCK(fdp);
535 break;
536
537 case F_GETFL:
538 FILEDESC_SLOCK(fdp);
539 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
540 if (error != 0) {
541 FILEDESC_SUNLOCK(fdp);
542 break;
543 }
544 td->td_retval[0] = OFLAGS(fp->f_flag);
545 FILEDESC_SUNLOCK(fdp);
546 break;
547
548 case F_SETFL:
549 FILEDESC_SLOCK(fdp);
550 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
551 if (error != 0) {
552 FILEDESC_SUNLOCK(fdp);
553 break;
554 }
555 fhold(fp);
556 FILEDESC_SUNLOCK(fdp);
557 do {
558 tmp = flg = fp->f_flag;
559 tmp &= ~FCNTLFLAGS;
560 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS;
561 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0);
562 tmp = fp->f_flag & FNONBLOCK;
563 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
564 if (error) {
565 fdrop(fp, td);
566 break;
567 }
568 tmp = fp->f_flag & FASYNC;
569 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td);
570 if (error == 0) {
571 fdrop(fp, td);
572 break;
573 }
574 atomic_clear_int(&fp->f_flag, FNONBLOCK);
575 tmp = 0;
576 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
577 fdrop(fp, td);
578 break;
579
580 case F_GETOWN:
581 FILEDESC_SLOCK(fdp);
582 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
583 if (error != 0) {
584 FILEDESC_SUNLOCK(fdp);
585 break;
586 }
587 fhold(fp);
588 FILEDESC_SUNLOCK(fdp);
589 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td);
590 if (error == 0)
591 td->td_retval[0] = tmp;
592 fdrop(fp, td);
593 break;
594
595 case F_SETOWN:
596 FILEDESC_SLOCK(fdp);
597 error = fdunwrap(fd, CAP_FCNTL, fdp, &fp);
598 if (error != 0) {
599 FILEDESC_SUNLOCK(fdp);
600 break;
601 }
602 fhold(fp);
603 FILEDESC_SUNLOCK(fdp);
604 tmp = arg;
605 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td);
606 fdrop(fp, td);
607 break;
608
609 case F_SETLK_REMOTE:
610 error = priv_check(td, PRIV_NFS_LOCKD);
611 if (error)
612 return (error);
613 flg = F_REMOTE;
614 goto do_setlk;
615
616 case F_SETLKW:
617 flg |= F_WAIT;
618 /* FALLTHROUGH F_SETLK */
619
620 case F_SETLK:
621 do_setlk:
622 FILEDESC_SLOCK(fdp);
623 error = fdunwrap(fd, CAP_FLOCK, fdp, &fp);
624 if (error != 0) {
625 FILEDESC_SUNLOCK(fdp);
626 break;
627 }
628 if (fp->f_type != DTYPE_VNODE) {
629 FILEDESC_SUNLOCK(fdp);
630 error = EBADF;
631 break;
632 }
633 flp = (struct flock *)arg;
634 if (flp->l_whence == SEEK_CUR) {
635 foffset = foffset_get(fp);
636 if (foffset < 0 ||
637 (flp->l_start > 0 &&
638 foffset > OFF_MAX - flp->l_start)) {
639 FILEDESC_SUNLOCK(fdp);
640 error = EOVERFLOW;
641 break;
642 }
643 flp->l_start += foffset;
644 }
645
646 /*
647 * VOP_ADVLOCK() may block.
648 */
649 fhold(fp);
650 FILEDESC_SUNLOCK(fdp);
651 vp = fp->f_vnode;
652 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
653 switch (flp->l_type) {
654 case F_RDLCK:
655 if ((fp->f_flag & FREAD) == 0) {
656 error = EBADF;
657 break;
658 }
659 PROC_LOCK(p->p_leader);
660 p->p_leader->p_flag |= P_ADVLOCK;
661 PROC_UNLOCK(p->p_leader);
662 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
663 flp, flg);
664 break;
665 case F_WRLCK:
666 if ((fp->f_flag & FWRITE) == 0) {
667 error = EBADF;
668 break;
669 }
670 PROC_LOCK(p->p_leader);
671 p->p_leader->p_flag |= P_ADVLOCK;
672 PROC_UNLOCK(p->p_leader);
673 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
674 flp, flg);
675 break;
676 case F_UNLCK:
677 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK,
678 flp, flg);
679 break;
680 case F_UNLCKSYS:
681 /*
682 * Temporary api for testing remote lock
683 * infrastructure.
684 */
685 if (flg != F_REMOTE) {
686 error = EINVAL;
687 break;
688 }
689 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
690 F_UNLCKSYS, flp, flg);
691 break;
692 default:
693 error = EINVAL;
694 break;
695 }
696 VFS_UNLOCK_GIANT(vfslocked);
697 vfslocked = 0;
698 /* Check for race with close */
699 FILEDESC_SLOCK(fdp);
700 if ((unsigned) fd >= fdp->fd_nfiles ||
701 fp != fdp->fd_ofiles[fd]) {
702 FILEDESC_SUNLOCK(fdp);
703 flp->l_whence = SEEK_SET;
704 flp->l_start = 0;
705 flp->l_len = 0;
706 flp->l_type = F_UNLCK;
707 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
708 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
709 F_UNLCK, flp, F_POSIX);
710 VFS_UNLOCK_GIANT(vfslocked);
711 vfslocked = 0;
712 } else
713 FILEDESC_SUNLOCK(fdp);
714 fdrop(fp, td);
715 break;
716
717 case F_GETLK:
718 FILEDESC_SLOCK(fdp);
719 error = fdunwrap(fd, CAP_FLOCK, fdp, &fp);
720 if (error != 0) {
721 FILEDESC_SUNLOCK(fdp);
722 break;
723 }
724 if (fp->f_type != DTYPE_VNODE) {
725 FILEDESC_SUNLOCK(fdp);
726 error = EBADF;
727 break;
728 }
729 flp = (struct flock *)arg;
730 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK &&
731 flp->l_type != F_UNLCK) {
732 FILEDESC_SUNLOCK(fdp);
733 error = EINVAL;
734 break;
735 }
736 if (flp->l_whence == SEEK_CUR) {
737 foffset = foffset_get(fp);
738 if ((flp->l_start > 0 &&
739 foffset > OFF_MAX - flp->l_start) ||
740 (flp->l_start < 0 &&
741 foffset < OFF_MIN - flp->l_start)) {
742 FILEDESC_SUNLOCK(fdp);
743 error = EOVERFLOW;
744 break;
745 }
746 flp->l_start += foffset;
747 }
748 /*
749 * VOP_ADVLOCK() may block.
750 */
751 fhold(fp);
752 FILEDESC_SUNLOCK(fdp);
753 vp = fp->f_vnode;
754 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
755 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp,
756 F_POSIX);
757 VFS_UNLOCK_GIANT(vfslocked);
758 vfslocked = 0;
759 fdrop(fp, td);
760 break;
761
762 case F_RDAHEAD:
763 arg = arg ? 128 * 1024: 0;
764 /* FALLTHROUGH */
765 case F_READAHEAD:
766 FILEDESC_SLOCK(fdp);
767 if ((fp = fdtofp(fd, fdp)) == NULL) {
768 FILEDESC_SUNLOCK(fdp);
769 error = EBADF;
770 break;
771 }
772 if (fp->f_type != DTYPE_VNODE) {
773 FILEDESC_SUNLOCK(fdp);
774 error = EBADF;
775 break;
776 }
777 fhold(fp);
778 FILEDESC_SUNLOCK(fdp);
779 if (arg != 0) {
780 vp = fp->f_vnode;
781 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
782 error = vn_lock(vp, LK_SHARED);
783 if (error != 0)
784 goto readahead_vnlock_fail;
785 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize;
786 VOP_UNLOCK(vp, 0);
787 fp->f_seqcount = (arg + bsize - 1) / bsize;
788 do {
789 new = old = fp->f_flag;
790 new |= FRDAHEAD;
791 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new));
792 readahead_vnlock_fail:
793 VFS_UNLOCK_GIANT(vfslocked);
794 vfslocked = 0;
795 } else {
796 do {
797 new = old = fp->f_flag;
798 new &= ~FRDAHEAD;
799 } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new));
800 }
801 fdrop(fp, td);
802 break;
803
804 default:
805 error = EINVAL;
806 break;
807 }
808 VFS_UNLOCK_GIANT(vfslocked);
809 return (error);
810 }
811
812 static int
813 getmaxfd(struct proc *p)
814 {
815 int maxfd;
816
817 PROC_LOCK(p);
818 maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc);
819 PROC_UNLOCK(p);
820
821 return (maxfd);
822 }
823
824 /*
825 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD).
826 */
827 static int
828 do_dup(struct thread *td, int flags, int old, int new,
829 register_t *retval)
830 {
831 struct filedesc *fdp;
832 struct proc *p;
833 struct file *fp;
834 struct file *delfp;
835 int error, holdleaders, maxfd;
836
837 p = td->td_proc;
838 fdp = p->p_fd;
839
840 /*
841 * Verify we have a valid descriptor to dup from and possibly to
842 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should
843 * return EINVAL when the new descriptor is out of bounds.
844 */
845 if (old < 0)
846 return (EBADF);
847 if (new < 0)
848 return (flags & DUP_FCNTL ? EINVAL : EBADF);
849 maxfd = getmaxfd(p);
850 if (new >= maxfd)
851 return (flags & DUP_FCNTL ? EINVAL : EBADF);
852
853 FILEDESC_XLOCK(fdp);
854 if (old >= fdp->fd_nfiles || fdp->fd_ofiles[old] == NULL) {
855 FILEDESC_XUNLOCK(fdp);
856 return (EBADF);
857 }
858 if (flags & DUP_FIXED && old == new) {
859 *retval = new;
860 if (flags & DUP_CLOEXEC)
861 fdp->fd_ofileflags[new] |= UF_EXCLOSE;
862 FILEDESC_XUNLOCK(fdp);
863 return (0);
864 }
865 fp = fdp->fd_ofiles[old];
866 fhold(fp);
867
868 /*
869 * If the caller specified a file descriptor, make sure the file
870 * table is large enough to hold it, and grab it. Otherwise, just
871 * allocate a new descriptor the usual way. Since the filedesc
872 * lock may be temporarily dropped in the process, we have to look
873 * out for a race.
874 */
875 if (flags & DUP_FIXED) {
876 if (new >= fdp->fd_nfiles) {
877 /*
878 * The resource limits are here instead of e.g.
879 * fdalloc(), because the file descriptor table may be
880 * shared between processes, so we can't really use
881 * racct_add()/racct_sub(). Instead of counting the
882 * number of actually allocated descriptors, just put
883 * the limit on the size of the file descriptor table.
884 */
885 #ifdef RACCT
886 PROC_LOCK(p);
887 error = racct_set(p, RACCT_NOFILE, new + 1);
888 PROC_UNLOCK(p);
889 if (error != 0) {
890 FILEDESC_XUNLOCK(fdp);
891 fdrop(fp, td);
892 return (EMFILE);
893 }
894 #endif
895 fdgrowtable(fdp, new + 1);
896 }
897 if (fdp->fd_ofiles[new] == NULL)
898 fdused(fdp, new);
899 } else {
900 if ((error = fdalloc(td, new, &new)) != 0) {
901 FILEDESC_XUNLOCK(fdp);
902 fdrop(fp, td);
903 return (error);
904 }
905 }
906
907 /*
908 * If the old file changed out from under us then treat it as a
909 * bad file descriptor. Userland should do its own locking to
910 * avoid this case.
911 */
912 if (fdp->fd_ofiles[old] != fp) {
913 /* we've allocated a descriptor which we won't use */
914 if (fdp->fd_ofiles[new] == NULL)
915 fdunused(fdp, new);
916 FILEDESC_XUNLOCK(fdp);
917 fdrop(fp, td);
918 return (EBADF);
919 }
920 KASSERT(old != new,
921 ("new fd is same as old"));
922
923 /*
924 * Save info on the descriptor being overwritten. We cannot close
925 * it without introducing an ownership race for the slot, since we
926 * need to drop the filedesc lock to call closef().
927 *
928 * XXX this duplicates parts of close().
929 */
930 delfp = fdp->fd_ofiles[new];
931 holdleaders = 0;
932 if (delfp != NULL) {
933 if (td->td_proc->p_fdtol != NULL) {
934 /*
935 * Ask fdfree() to sleep to ensure that all relevant
936 * process leaders can be traversed in closef().
937 */
938 fdp->fd_holdleaderscount++;
939 holdleaders = 1;
940 }
941 }
942
943 /*
944 * Duplicate the source descriptor
945 */
946 fdp->fd_ofiles[new] = fp;
947 if ((flags & DUP_CLOEXEC) != 0)
948 fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] | UF_EXCLOSE;
949 else
950 fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] & ~UF_EXCLOSE;
951 if (new > fdp->fd_lastfile)
952 fdp->fd_lastfile = new;
953 *retval = new;
954
955 /*
956 * If we dup'd over a valid file, we now own the reference to it
957 * and must dispose of it using closef() semantics (as if a
958 * close() were performed on it).
959 *
960 * XXX this duplicates parts of close().
961 */
962 if (delfp != NULL) {
963 knote_fdclose(td, new);
964 if (delfp->f_type == DTYPE_MQUEUE)
965 mq_fdclose(td, new, delfp);
966 FILEDESC_XUNLOCK(fdp);
967 (void) closef(delfp, td);
968 if (holdleaders) {
969 FILEDESC_XLOCK(fdp);
970 fdp->fd_holdleaderscount--;
971 if (fdp->fd_holdleaderscount == 0 &&
972 fdp->fd_holdleaderswakeup != 0) {
973 fdp->fd_holdleaderswakeup = 0;
974 wakeup(&fdp->fd_holdleaderscount);
975 }
976 FILEDESC_XUNLOCK(fdp);
977 }
978 } else {
979 FILEDESC_XUNLOCK(fdp);
980 }
981 return (0);
982 }
983
984 /*
985 * If sigio is on the list associated with a process or process group,
986 * disable signalling from the device, remove sigio from the list and
987 * free sigio.
988 */
989 void
990 funsetown(struct sigio **sigiop)
991 {
992 struct sigio *sigio;
993
994 SIGIO_LOCK();
995 sigio = *sigiop;
996 if (sigio == NULL) {
997 SIGIO_UNLOCK();
998 return;
999 }
1000 *(sigio->sio_myref) = NULL;
1001 if ((sigio)->sio_pgid < 0) {
1002 struct pgrp *pg = (sigio)->sio_pgrp;
1003 PGRP_LOCK(pg);
1004 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio,
1005 sigio, sio_pgsigio);
1006 PGRP_UNLOCK(pg);
1007 } else {
1008 struct proc *p = (sigio)->sio_proc;
1009 PROC_LOCK(p);
1010 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio,
1011 sigio, sio_pgsigio);
1012 PROC_UNLOCK(p);
1013 }
1014 SIGIO_UNLOCK();
1015 crfree(sigio->sio_ucred);
1016 free(sigio, M_SIGIO);
1017 }
1018
1019 /*
1020 * Free a list of sigio structures.
1021 * We only need to lock the SIGIO_LOCK because we have made ourselves
1022 * inaccessible to callers of fsetown and therefore do not need to lock
1023 * the proc or pgrp struct for the list manipulation.
1024 */
1025 void
1026 funsetownlst(struct sigiolst *sigiolst)
1027 {
1028 struct proc *p;
1029 struct pgrp *pg;
1030 struct sigio *sigio;
1031
1032 sigio = SLIST_FIRST(sigiolst);
1033 if (sigio == NULL)
1034 return;
1035 p = NULL;
1036 pg = NULL;
1037
1038 /*
1039 * Every entry of the list should belong
1040 * to a single proc or pgrp.
1041 */
1042 if (sigio->sio_pgid < 0) {
1043 pg = sigio->sio_pgrp;
1044 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED);
1045 } else /* if (sigio->sio_pgid > 0) */ {
1046 p = sigio->sio_proc;
1047 PROC_LOCK_ASSERT(p, MA_NOTOWNED);
1048 }
1049
1050 SIGIO_LOCK();
1051 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) {
1052 *(sigio->sio_myref) = NULL;
1053 if (pg != NULL) {
1054 KASSERT(sigio->sio_pgid < 0,
1055 ("Proc sigio in pgrp sigio list"));
1056 KASSERT(sigio->sio_pgrp == pg,
1057 ("Bogus pgrp in sigio list"));
1058 PGRP_LOCK(pg);
1059 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio,
1060 sio_pgsigio);
1061 PGRP_UNLOCK(pg);
1062 } else /* if (p != NULL) */ {
1063 KASSERT(sigio->sio_pgid > 0,
1064 ("Pgrp sigio in proc sigio list"));
1065 KASSERT(sigio->sio_proc == p,
1066 ("Bogus proc in sigio list"));
1067 PROC_LOCK(p);
1068 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio,
1069 sio_pgsigio);
1070 PROC_UNLOCK(p);
1071 }
1072 SIGIO_UNLOCK();
1073 crfree(sigio->sio_ucred);
1074 free(sigio, M_SIGIO);
1075 SIGIO_LOCK();
1076 }
1077 SIGIO_UNLOCK();
1078 }
1079
1080 /*
1081 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg).
1082 *
1083 * After permission checking, add a sigio structure to the sigio list for
1084 * the process or process group.
1085 */
1086 int
1087 fsetown(pid_t pgid, struct sigio **sigiop)
1088 {
1089 struct proc *proc;
1090 struct pgrp *pgrp;
1091 struct sigio *sigio;
1092 int ret;
1093
1094 if (pgid == 0) {
1095 funsetown(sigiop);
1096 return (0);
1097 }
1098
1099 ret = 0;
1100
1101 /* Allocate and fill in the new sigio out of locks. */
1102 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK);
1103 sigio->sio_pgid = pgid;
1104 sigio->sio_ucred = crhold(curthread->td_ucred);
1105 sigio->sio_myref = sigiop;
1106
1107 sx_slock(&proctree_lock);
1108 if (pgid > 0) {
1109 proc = pfind(pgid);
1110 if (proc == NULL) {
1111 ret = ESRCH;
1112 goto fail;
1113 }
1114
1115 /*
1116 * Policy - Don't allow a process to FSETOWN a process
1117 * in another session.
1118 *
1119 * Remove this test to allow maximum flexibility or
1120 * restrict FSETOWN to the current process or process
1121 * group for maximum safety.
1122 */
1123 PROC_UNLOCK(proc);
1124 if (proc->p_session != curthread->td_proc->p_session) {
1125 ret = EPERM;
1126 goto fail;
1127 }
1128
1129 pgrp = NULL;
1130 } else /* if (pgid < 0) */ {
1131 pgrp = pgfind(-pgid);
1132 if (pgrp == NULL) {
1133 ret = ESRCH;
1134 goto fail;
1135 }
1136 PGRP_UNLOCK(pgrp);
1137
1138 /*
1139 * Policy - Don't allow a process to FSETOWN a process
1140 * in another session.
1141 *
1142 * Remove this test to allow maximum flexibility or
1143 * restrict FSETOWN to the current process or process
1144 * group for maximum safety.
1145 */
1146 if (pgrp->pg_session != curthread->td_proc->p_session) {
1147 ret = EPERM;
1148 goto fail;
1149 }
1150
1151 proc = NULL;
1152 }
1153 funsetown(sigiop);
1154 if (pgid > 0) {
1155 PROC_LOCK(proc);
1156 /*
1157 * Since funsetownlst() is called without the proctree
1158 * locked, we need to check for P_WEXIT.
1159 * XXX: is ESRCH correct?
1160 */
1161 if ((proc->p_flag & P_WEXIT) != 0) {
1162 PROC_UNLOCK(proc);
1163 ret = ESRCH;
1164 goto fail;
1165 }
1166 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio);
1167 sigio->sio_proc = proc;
1168 PROC_UNLOCK(proc);
1169 } else {
1170 PGRP_LOCK(pgrp);
1171 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio);
1172 sigio->sio_pgrp = pgrp;
1173 PGRP_UNLOCK(pgrp);
1174 }
1175 sx_sunlock(&proctree_lock);
1176 SIGIO_LOCK();
1177 *sigiop = sigio;
1178 SIGIO_UNLOCK();
1179 return (0);
1180
1181 fail:
1182 sx_sunlock(&proctree_lock);
1183 crfree(sigio->sio_ucred);
1184 free(sigio, M_SIGIO);
1185 return (ret);
1186 }
1187
1188 /*
1189 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg).
1190 */
1191 pid_t
1192 fgetown(sigiop)
1193 struct sigio **sigiop;
1194 {
1195 pid_t pgid;
1196
1197 SIGIO_LOCK();
1198 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0;
1199 SIGIO_UNLOCK();
1200 return (pgid);
1201 }
1202
1203 /*
1204 * Close a file descriptor.
1205 */
1206 #ifndef _SYS_SYSPROTO_H_
1207 struct close_args {
1208 int fd;
1209 };
1210 #endif
1211 /* ARGSUSED */
1212 int
1213 sys_close(td, uap)
1214 struct thread *td;
1215 struct close_args *uap;
1216 {
1217
1218 return (kern_close(td, uap->fd));
1219 }
1220
1221 int
1222 kern_close(td, fd)
1223 struct thread *td;
1224 int fd;
1225 {
1226 struct filedesc *fdp;
1227 struct file *fp, *fp_object;
1228 int error;
1229 int holdleaders;
1230
1231 error = 0;
1232 holdleaders = 0;
1233 fdp = td->td_proc->p_fd;
1234
1235 AUDIT_SYSCLOSE(td, fd);
1236
1237 FILEDESC_XLOCK(fdp);
1238 if ((unsigned)fd >= fdp->fd_nfiles ||
1239 (fp = fdp->fd_ofiles[fd]) == NULL) {
1240 FILEDESC_XUNLOCK(fdp);
1241 return (EBADF);
1242 }
1243 fdp->fd_ofiles[fd] = NULL;
1244 fdp->fd_ofileflags[fd] = 0;
1245 fdunused(fdp, fd);
1246 if (td->td_proc->p_fdtol != NULL) {
1247 /*
1248 * Ask fdfree() to sleep to ensure that all relevant
1249 * process leaders can be traversed in closef().
1250 */
1251 fdp->fd_holdleaderscount++;
1252 holdleaders = 1;
1253 }
1254
1255 /*
1256 * We now hold the fp reference that used to be owned by the
1257 * descriptor array. We have to unlock the FILEDESC *AFTER*
1258 * knote_fdclose to prevent a race of the fd getting opened, a knote
1259 * added, and deleteing a knote for the new fd.
1260 */
1261 knote_fdclose(td, fd);
1262
1263 /*
1264 * When we're closing an fd with a capability, we need to notify
1265 * mqueue if the underlying object is of type mqueue.
1266 */
1267 (void)cap_funwrap(fp, 0, &fp_object);
1268 if (fp_object->f_type == DTYPE_MQUEUE)
1269 mq_fdclose(td, fd, fp_object);
1270 FILEDESC_XUNLOCK(fdp);
1271
1272 error = closef(fp, td);
1273 if (holdleaders) {
1274 FILEDESC_XLOCK(fdp);
1275 fdp->fd_holdleaderscount--;
1276 if (fdp->fd_holdleaderscount == 0 &&
1277 fdp->fd_holdleaderswakeup != 0) {
1278 fdp->fd_holdleaderswakeup = 0;
1279 wakeup(&fdp->fd_holdleaderscount);
1280 }
1281 FILEDESC_XUNLOCK(fdp);
1282 }
1283 return (error);
1284 }
1285
1286 /*
1287 * Close open file descriptors.
1288 */
1289 #ifndef _SYS_SYSPROTO_H_
1290 struct closefrom_args {
1291 int lowfd;
1292 };
1293 #endif
1294 /* ARGSUSED */
1295 int
1296 sys_closefrom(struct thread *td, struct closefrom_args *uap)
1297 {
1298 struct filedesc *fdp;
1299 int fd;
1300
1301 fdp = td->td_proc->p_fd;
1302 AUDIT_ARG_FD(uap->lowfd);
1303
1304 /*
1305 * Treat negative starting file descriptor values identical to
1306 * closefrom(0) which closes all files.
1307 */
1308 if (uap->lowfd < 0)
1309 uap->lowfd = 0;
1310 FILEDESC_SLOCK(fdp);
1311 for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) {
1312 if (fdp->fd_ofiles[fd] != NULL) {
1313 FILEDESC_SUNLOCK(fdp);
1314 (void)kern_close(td, fd);
1315 FILEDESC_SLOCK(fdp);
1316 }
1317 }
1318 FILEDESC_SUNLOCK(fdp);
1319 return (0);
1320 }
1321
1322 #if defined(COMPAT_43)
1323 /*
1324 * Return status information about a file descriptor.
1325 */
1326 #ifndef _SYS_SYSPROTO_H_
1327 struct ofstat_args {
1328 int fd;
1329 struct ostat *sb;
1330 };
1331 #endif
1332 /* ARGSUSED */
1333 int
1334 ofstat(struct thread *td, struct ofstat_args *uap)
1335 {
1336 struct ostat oub;
1337 struct stat ub;
1338 int error;
1339
1340 error = kern_fstat(td, uap->fd, &ub);
1341 if (error == 0) {
1342 cvtstat(&ub, &oub);
1343 error = copyout(&oub, uap->sb, sizeof(oub));
1344 }
1345 return (error);
1346 }
1347 #endif /* COMPAT_43 */
1348
1349 /*
1350 * Return status information about a file descriptor.
1351 */
1352 #ifndef _SYS_SYSPROTO_H_
1353 struct fstat_args {
1354 int fd;
1355 struct stat *sb;
1356 };
1357 #endif
1358 /* ARGSUSED */
1359 int
1360 sys_fstat(struct thread *td, struct fstat_args *uap)
1361 {
1362 struct stat ub;
1363 int error;
1364
1365 error = kern_fstat(td, uap->fd, &ub);
1366 if (error == 0)
1367 error = copyout(&ub, uap->sb, sizeof(ub));
1368 return (error);
1369 }
1370
1371 int
1372 kern_fstat(struct thread *td, int fd, struct stat *sbp)
1373 {
1374 struct file *fp;
1375 int error;
1376
1377 AUDIT_ARG_FD(fd);
1378
1379 if ((error = fget(td, fd, CAP_FSTAT, &fp)) != 0)
1380 return (error);
1381
1382 AUDIT_ARG_FILE(td->td_proc, fp);
1383
1384 error = fo_stat(fp, sbp, td->td_ucred, td);
1385 fdrop(fp, td);
1386 #ifdef KTRACE
1387 if (error == 0 && KTRPOINT(td, KTR_STRUCT))
1388 ktrstat(sbp);
1389 #endif
1390 return (error);
1391 }
1392
1393 /*
1394 * Return status information about a file descriptor.
1395 */
1396 #ifndef _SYS_SYSPROTO_H_
1397 struct nfstat_args {
1398 int fd;
1399 struct nstat *sb;
1400 };
1401 #endif
1402 /* ARGSUSED */
1403 int
1404 sys_nfstat(struct thread *td, struct nfstat_args *uap)
1405 {
1406 struct nstat nub;
1407 struct stat ub;
1408 int error;
1409
1410 error = kern_fstat(td, uap->fd, &ub);
1411 if (error == 0) {
1412 cvtnstat(&ub, &nub);
1413 error = copyout(&nub, uap->sb, sizeof(nub));
1414 }
1415 return (error);
1416 }
1417
1418 /*
1419 * Return pathconf information about a file descriptor.
1420 */
1421 #ifndef _SYS_SYSPROTO_H_
1422 struct fpathconf_args {
1423 int fd;
1424 int name;
1425 };
1426 #endif
1427 /* ARGSUSED */
1428 int
1429 sys_fpathconf(struct thread *td, struct fpathconf_args *uap)
1430 {
1431 struct file *fp;
1432 struct vnode *vp;
1433 int error;
1434
1435 if ((error = fget(td, uap->fd, CAP_FPATHCONF, &fp)) != 0)
1436 return (error);
1437
1438 /* If asynchronous I/O is available, it works for all descriptors. */
1439 if (uap->name == _PC_ASYNC_IO) {
1440 td->td_retval[0] = async_io_version;
1441 goto out;
1442 }
1443 vp = fp->f_vnode;
1444 if (vp != NULL) {
1445 int vfslocked;
1446 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
1447 vn_lock(vp, LK_SHARED | LK_RETRY);
1448 error = VOP_PATHCONF(vp, uap->name, td->td_retval);
1449 VOP_UNLOCK(vp, 0);
1450 VFS_UNLOCK_GIANT(vfslocked);
1451 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) {
1452 if (uap->name != _PC_PIPE_BUF) {
1453 error = EINVAL;
1454 } else {
1455 td->td_retval[0] = PIPE_BUF;
1456 error = 0;
1457 }
1458 } else {
1459 error = EOPNOTSUPP;
1460 }
1461 out:
1462 fdrop(fp, td);
1463 return (error);
1464 }
1465
1466 /*
1467 * Grow the file table to accomodate (at least) nfd descriptors. This may
1468 * block and drop the filedesc lock, but it will reacquire it before
1469 * returning.
1470 */
1471 static void
1472 fdgrowtable(struct filedesc *fdp, int nfd)
1473 {
1474 struct filedesc0 *fdp0;
1475 struct freetable *fo;
1476 struct file **ntable;
1477 struct file **otable;
1478 char *nfileflags;
1479 int nnfiles, onfiles;
1480 NDSLOTTYPE *nmap;
1481
1482 FILEDESC_XLOCK_ASSERT(fdp);
1483
1484 KASSERT(fdp->fd_nfiles > 0,
1485 ("zero-length file table"));
1486
1487 /* compute the size of the new table */
1488 onfiles = fdp->fd_nfiles;
1489 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */
1490 if (nnfiles <= onfiles)
1491 /* the table is already large enough */
1492 return;
1493
1494 /* allocate a new table and (if required) new bitmaps */
1495 FILEDESC_XUNLOCK(fdp);
1496 ntable = malloc((nnfiles * OFILESIZE) + sizeof(struct freetable),
1497 M_FILEDESC, M_ZERO | M_WAITOK);
1498 nfileflags = (char *)&ntable[nnfiles];
1499 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles))
1500 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE,
1501 M_FILEDESC, M_ZERO | M_WAITOK);
1502 else
1503 nmap = NULL;
1504 FILEDESC_XLOCK(fdp);
1505
1506 /*
1507 * We now have new tables ready to go. Since we dropped the
1508 * filedesc lock to call malloc(), watch out for a race.
1509 */
1510 onfiles = fdp->fd_nfiles;
1511 if (onfiles >= nnfiles) {
1512 /* we lost the race, but that's OK */
1513 free(ntable, M_FILEDESC);
1514 if (nmap != NULL)
1515 free(nmap, M_FILEDESC);
1516 return;
1517 }
1518 bcopy(fdp->fd_ofiles, ntable, onfiles * sizeof(*ntable));
1519 bcopy(fdp->fd_ofileflags, nfileflags, onfiles);
1520 otable = fdp->fd_ofiles;
1521 fdp->fd_ofileflags = nfileflags;
1522 fdp->fd_ofiles = ntable;
1523 /*
1524 * We must preserve ofiles until the process exits because we can't
1525 * be certain that no threads have references to the old table via
1526 * _fget().
1527 */
1528 if (onfiles > NDFILE) {
1529 fo = (struct freetable *)&otable[onfiles];
1530 fdp0 = (struct filedesc0 *)fdp;
1531 fo->ft_table = otable;
1532 SLIST_INSERT_HEAD(&fdp0->fd_free, fo, ft_next);
1533 }
1534 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) {
1535 bcopy(fdp->fd_map, nmap, NDSLOTS(onfiles) * sizeof(*nmap));
1536 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE))
1537 free(fdp->fd_map, M_FILEDESC);
1538 fdp->fd_map = nmap;
1539 }
1540 fdp->fd_nfiles = nnfiles;
1541 }
1542
1543 /*
1544 * Allocate a file descriptor for the process.
1545 */
1546 int
1547 fdalloc(struct thread *td, int minfd, int *result)
1548 {
1549 struct proc *p = td->td_proc;
1550 struct filedesc *fdp = p->p_fd;
1551 int fd = -1, maxfd;
1552 #ifdef RACCT
1553 int error;
1554 #endif
1555
1556 FILEDESC_XLOCK_ASSERT(fdp);
1557
1558 if (fdp->fd_freefile > minfd)
1559 minfd = fdp->fd_freefile;
1560
1561 maxfd = getmaxfd(p);
1562
1563 /*
1564 * Search the bitmap for a free descriptor. If none is found, try
1565 * to grow the file table. Keep at it until we either get a file
1566 * descriptor or run into process or system limits; fdgrowtable()
1567 * may drop the filedesc lock, so we're in a race.
1568 */
1569 for (;;) {
1570 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles);
1571 if (fd >= maxfd)
1572 return (EMFILE);
1573 if (fd < fdp->fd_nfiles)
1574 break;
1575 #ifdef RACCT
1576 PROC_LOCK(p);
1577 error = racct_set(p, RACCT_NOFILE, min(fdp->fd_nfiles * 2, maxfd));
1578 PROC_UNLOCK(p);
1579 if (error != 0)
1580 return (EMFILE);
1581 #endif
1582 fdgrowtable(fdp, min(fdp->fd_nfiles * 2, maxfd));
1583 }
1584
1585 /*
1586 * Perform some sanity checks, then mark the file descriptor as
1587 * used and return it to the caller.
1588 */
1589 KASSERT(!fdisused(fdp, fd),
1590 ("fd_first_free() returned non-free descriptor"));
1591 KASSERT(fdp->fd_ofiles[fd] == NULL,
1592 ("free descriptor isn't"));
1593 fdp->fd_ofileflags[fd] = 0; /* XXX needed? */
1594 fdused(fdp, fd);
1595 *result = fd;
1596 return (0);
1597 }
1598
1599 /*
1600 * Allocate n file descriptors for the process.
1601 */
1602 int
1603 fdallocn(struct thread *td, int minfd, int *fds, int n)
1604 {
1605 struct proc *p = td->td_proc;
1606 struct filedesc *fdp = p->p_fd;
1607 int i;
1608
1609 FILEDESC_XLOCK_ASSERT(fdp);
1610
1611 if (!fdavail(td, n))
1612 return (EMFILE);
1613
1614 for (i = 0; i < n; i++)
1615 if (fdalloc(td, 0, &fds[i]) != 0)
1616 break;
1617
1618 if (i < n) {
1619 for (i--; i >= 0; i--)
1620 fdunused(fdp, fds[i]);
1621 return (EMFILE);
1622 }
1623
1624 return (0);
1625 }
1626
1627 /*
1628 * Check to see whether n user file descriptors are available to the process
1629 * p.
1630 */
1631 int
1632 fdavail(struct thread *td, int n)
1633 {
1634 struct proc *p = td->td_proc;
1635 struct filedesc *fdp = td->td_proc->p_fd;
1636 struct file **fpp;
1637 int i, lim, last;
1638
1639 FILEDESC_LOCK_ASSERT(fdp);
1640
1641 /*
1642 * XXX: This is only called from uipc_usrreq.c:unp_externalize();
1643 * call racct_add() from there instead of dealing with containers
1644 * here.
1645 */
1646 lim = getmaxfd(p);
1647 if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0)
1648 return (1);
1649 last = min(fdp->fd_nfiles, lim);
1650 fpp = &fdp->fd_ofiles[fdp->fd_freefile];
1651 for (i = last - fdp->fd_freefile; --i >= 0; fpp++) {
1652 if (*fpp == NULL && --n <= 0)
1653 return (1);
1654 }
1655 return (0);
1656 }
1657
1658 /*
1659 * Create a new open file structure and allocate a file decriptor for the
1660 * process that refers to it. We add one reference to the file for the
1661 * descriptor table and one reference for resultfp. This is to prevent us
1662 * being preempted and the entry in the descriptor table closed after we
1663 * release the FILEDESC lock.
1664 */
1665 int
1666 falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags)
1667 {
1668 struct file *fp;
1669 int error, fd;
1670
1671 error = falloc_noinstall(td, &fp);
1672 if (error)
1673 return (error); /* no reference held on error */
1674
1675 error = finstall(td, fp, &fd, flags);
1676 if (error) {
1677 fdrop(fp, td); /* one reference (fp only) */
1678 return (error);
1679 }
1680
1681 if (resultfp != NULL)
1682 *resultfp = fp; /* copy out result */
1683 else
1684 fdrop(fp, td); /* release local reference */
1685
1686 if (resultfd != NULL)
1687 *resultfd = fd;
1688
1689 return (0);
1690 }
1691
1692 /*
1693 * Create a new open file structure without allocating a file descriptor.
1694 */
1695 int
1696 falloc_noinstall(struct thread *td, struct file **resultfp)
1697 {
1698 struct file *fp;
1699 int maxuserfiles = maxfiles - (maxfiles / 20);
1700 static struct timeval lastfail;
1701 static int curfail;
1702
1703 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__));
1704
1705 if ((openfiles >= maxuserfiles &&
1706 priv_check(td, PRIV_MAXFILES) != 0) ||
1707 openfiles >= maxfiles) {
1708 if (ppsratecheck(&lastfail, &curfail, 1)) {
1709 printf("kern.maxfiles limit exceeded by uid %i, "
1710 "please see tuning(7).\n", td->td_ucred->cr_ruid);
1711 }
1712 return (ENFILE);
1713 }
1714 atomic_add_int(&openfiles, 1);
1715 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO);
1716 refcount_init(&fp->f_count, 1);
1717 fp->f_cred = crhold(td->td_ucred);
1718 fp->f_ops = &badfileops;
1719 fp->f_data = NULL;
1720 fp->f_vnode = NULL;
1721 *resultfp = fp;
1722 return (0);
1723 }
1724
1725 /*
1726 * Install a file in a file descriptor table.
1727 */
1728 int
1729 finstall(struct thread *td, struct file *fp, int *fd, int flags)
1730 {
1731 struct filedesc *fdp = td->td_proc->p_fd;
1732 int error;
1733
1734 KASSERT(fd != NULL, ("%s: fd == NULL", __func__));
1735 KASSERT(fp != NULL, ("%s: fp == NULL", __func__));
1736
1737 FILEDESC_XLOCK(fdp);
1738 if ((error = fdalloc(td, 0, fd))) {
1739 FILEDESC_XUNLOCK(fdp);
1740 return (error);
1741 }
1742 fhold(fp);
1743 fdp->fd_ofiles[*fd] = fp;
1744 if ((flags & O_CLOEXEC) != 0)
1745 fdp->fd_ofileflags[*fd] |= UF_EXCLOSE;
1746 FILEDESC_XUNLOCK(fdp);
1747 return (0);
1748 }
1749
1750 /*
1751 * Build a new filedesc structure from another.
1752 * Copy the current, root, and jail root vnode references.
1753 */
1754 struct filedesc *
1755 fdinit(struct filedesc *fdp)
1756 {
1757 struct filedesc0 *newfdp;
1758
1759 newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO);
1760 FILEDESC_LOCK_INIT(&newfdp->fd_fd);
1761 if (fdp != NULL) {
1762 FILEDESC_XLOCK(fdp);
1763 newfdp->fd_fd.fd_cdir = fdp->fd_cdir;
1764 if (newfdp->fd_fd.fd_cdir)
1765 VREF(newfdp->fd_fd.fd_cdir);
1766 newfdp->fd_fd.fd_rdir = fdp->fd_rdir;
1767 if (newfdp->fd_fd.fd_rdir)
1768 VREF(newfdp->fd_fd.fd_rdir);
1769 newfdp->fd_fd.fd_jdir = fdp->fd_jdir;
1770 if (newfdp->fd_fd.fd_jdir)
1771 VREF(newfdp->fd_fd.fd_jdir);
1772 FILEDESC_XUNLOCK(fdp);
1773 }
1774
1775 /* Create the file descriptor table. */
1776 newfdp->fd_fd.fd_refcnt = 1;
1777 newfdp->fd_fd.fd_holdcnt = 1;
1778 newfdp->fd_fd.fd_cmask = CMASK;
1779 newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles;
1780 newfdp->fd_fd.fd_ofileflags = newfdp->fd_dfileflags;
1781 newfdp->fd_fd.fd_nfiles = NDFILE;
1782 newfdp->fd_fd.fd_map = newfdp->fd_dmap;
1783 newfdp->fd_fd.fd_lastfile = -1;
1784 return (&newfdp->fd_fd);
1785 }
1786
1787 static struct filedesc *
1788 fdhold(struct proc *p)
1789 {
1790 struct filedesc *fdp;
1791
1792 mtx_lock(&fdesc_mtx);
1793 fdp = p->p_fd;
1794 if (fdp != NULL)
1795 fdp->fd_holdcnt++;
1796 mtx_unlock(&fdesc_mtx);
1797 return (fdp);
1798 }
1799
1800 static void
1801 fddrop(struct filedesc *fdp)
1802 {
1803 struct filedesc0 *fdp0;
1804 struct freetable *ft;
1805 int i;
1806
1807 mtx_lock(&fdesc_mtx);
1808 i = --fdp->fd_holdcnt;
1809 mtx_unlock(&fdesc_mtx);
1810 if (i > 0)
1811 return;
1812
1813 FILEDESC_LOCK_DESTROY(fdp);
1814 fdp0 = (struct filedesc0 *)fdp;
1815 while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) {
1816 SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next);
1817 free(ft->ft_table, M_FILEDESC);
1818 }
1819 free(fdp, M_FILEDESC);
1820 }
1821
1822 /*
1823 * Share a filedesc structure.
1824 */
1825 struct filedesc *
1826 fdshare(struct filedesc *fdp)
1827 {
1828
1829 FILEDESC_XLOCK(fdp);
1830 fdp->fd_refcnt++;
1831 FILEDESC_XUNLOCK(fdp);
1832 return (fdp);
1833 }
1834
1835 /*
1836 * Unshare a filedesc structure, if necessary by making a copy
1837 */
1838 void
1839 fdunshare(struct proc *p, struct thread *td)
1840 {
1841
1842 FILEDESC_XLOCK(p->p_fd);
1843 if (p->p_fd->fd_refcnt > 1) {
1844 struct filedesc *tmp;
1845
1846 FILEDESC_XUNLOCK(p->p_fd);
1847 tmp = fdcopy(p->p_fd);
1848 fdfree(td);
1849 p->p_fd = tmp;
1850 } else
1851 FILEDESC_XUNLOCK(p->p_fd);
1852 }
1853
1854 /*
1855 * Copy a filedesc structure. A NULL pointer in returns a NULL reference,
1856 * this is to ease callers, not catch errors.
1857 */
1858 struct filedesc *
1859 fdcopy(struct filedesc *fdp)
1860 {
1861 struct filedesc *newfdp;
1862 int i;
1863
1864 /* Certain daemons might not have file descriptors. */
1865 if (fdp == NULL)
1866 return (NULL);
1867
1868 newfdp = fdinit(fdp);
1869 FILEDESC_SLOCK(fdp);
1870 while (fdp->fd_lastfile >= newfdp->fd_nfiles) {
1871 FILEDESC_SUNLOCK(fdp);
1872 FILEDESC_XLOCK(newfdp);
1873 fdgrowtable(newfdp, fdp->fd_lastfile + 1);
1874 FILEDESC_XUNLOCK(newfdp);
1875 FILEDESC_SLOCK(fdp);
1876 }
1877 /* copy all passable descriptors (i.e. not kqueue) */
1878 newfdp->fd_freefile = -1;
1879 for (i = 0; i <= fdp->fd_lastfile; ++i) {
1880 if (fdisused(fdp, i) &&
1881 (fdp->fd_ofiles[i]->f_ops->fo_flags & DFLAG_PASSABLE) &&
1882 fdp->fd_ofiles[i]->f_ops != &badfileops) {
1883 newfdp->fd_ofiles[i] = fdp->fd_ofiles[i];
1884 newfdp->fd_ofileflags[i] = fdp->fd_ofileflags[i];
1885 fhold(newfdp->fd_ofiles[i]);
1886 newfdp->fd_lastfile = i;
1887 } else {
1888 if (newfdp->fd_freefile == -1)
1889 newfdp->fd_freefile = i;
1890 }
1891 }
1892 newfdp->fd_cmask = fdp->fd_cmask;
1893 FILEDESC_SUNLOCK(fdp);
1894 FILEDESC_XLOCK(newfdp);
1895 for (i = 0; i <= newfdp->fd_lastfile; ++i)
1896 if (newfdp->fd_ofiles[i] != NULL)
1897 fdused(newfdp, i);
1898 if (newfdp->fd_freefile == -1)
1899 newfdp->fd_freefile = i;
1900 FILEDESC_XUNLOCK(newfdp);
1901 return (newfdp);
1902 }
1903
1904 /*
1905 * Release a filedesc structure.
1906 */
1907 void
1908 fdfree(struct thread *td)
1909 {
1910 struct filedesc *fdp;
1911 struct file **fpp;
1912 int i, locked;
1913 struct filedesc_to_leader *fdtol;
1914 struct file *fp;
1915 struct vnode *cdir, *jdir, *rdir, *vp;
1916 struct flock lf;
1917
1918 /* Certain daemons might not have file descriptors. */
1919 fdp = td->td_proc->p_fd;
1920 if (fdp == NULL)
1921 return;
1922
1923 #ifdef RACCT
1924 PROC_LOCK(td->td_proc);
1925 racct_set(td->td_proc, RACCT_NOFILE, 0);
1926 PROC_UNLOCK(td->td_proc);
1927 #endif
1928
1929 /* Check for special need to clear POSIX style locks */
1930 fdtol = td->td_proc->p_fdtol;
1931 if (fdtol != NULL) {
1932 FILEDESC_XLOCK(fdp);
1933 KASSERT(fdtol->fdl_refcount > 0,
1934 ("filedesc_to_refcount botch: fdl_refcount=%d",
1935 fdtol->fdl_refcount));
1936 if (fdtol->fdl_refcount == 1 &&
1937 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
1938 for (i = 0, fpp = fdp->fd_ofiles;
1939 i <= fdp->fd_lastfile;
1940 i++, fpp++) {
1941 if (*fpp == NULL ||
1942 (*fpp)->f_type != DTYPE_VNODE)
1943 continue;
1944 fp = *fpp;
1945 fhold(fp);
1946 FILEDESC_XUNLOCK(fdp);
1947 lf.l_whence = SEEK_SET;
1948 lf.l_start = 0;
1949 lf.l_len = 0;
1950 lf.l_type = F_UNLCK;
1951 vp = fp->f_vnode;
1952 locked = VFS_LOCK_GIANT(vp->v_mount);
1953 (void) VOP_ADVLOCK(vp,
1954 (caddr_t)td->td_proc->
1955 p_leader,
1956 F_UNLCK,
1957 &lf,
1958 F_POSIX);
1959 VFS_UNLOCK_GIANT(locked);
1960 FILEDESC_XLOCK(fdp);
1961 fdrop(fp, td);
1962 fpp = fdp->fd_ofiles + i;
1963 }
1964 }
1965 retry:
1966 if (fdtol->fdl_refcount == 1) {
1967 if (fdp->fd_holdleaderscount > 0 &&
1968 (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
1969 /*
1970 * close() or do_dup() has cleared a reference
1971 * in a shared file descriptor table.
1972 */
1973 fdp->fd_holdleaderswakeup = 1;
1974 sx_sleep(&fdp->fd_holdleaderscount,
1975 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0);
1976 goto retry;
1977 }
1978 if (fdtol->fdl_holdcount > 0) {
1979 /*
1980 * Ensure that fdtol->fdl_leader remains
1981 * valid in closef().
1982 */
1983 fdtol->fdl_wakeup = 1;
1984 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK,
1985 "fdlhold", 0);
1986 goto retry;
1987 }
1988 }
1989 fdtol->fdl_refcount--;
1990 if (fdtol->fdl_refcount == 0 &&
1991 fdtol->fdl_holdcount == 0) {
1992 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev;
1993 fdtol->fdl_prev->fdl_next = fdtol->fdl_next;
1994 } else
1995 fdtol = NULL;
1996 td->td_proc->p_fdtol = NULL;
1997 FILEDESC_XUNLOCK(fdp);
1998 if (fdtol != NULL)
1999 free(fdtol, M_FILEDESC_TO_LEADER);
2000 }
2001 FILEDESC_XLOCK(fdp);
2002 i = --fdp->fd_refcnt;
2003 FILEDESC_XUNLOCK(fdp);
2004 if (i > 0)
2005 return;
2006
2007 fpp = fdp->fd_ofiles;
2008 for (i = fdp->fd_lastfile; i-- >= 0; fpp++) {
2009 if (*fpp) {
2010 FILEDESC_XLOCK(fdp);
2011 fp = *fpp;
2012 *fpp = NULL;
2013 FILEDESC_XUNLOCK(fdp);
2014 (void) closef(fp, td);
2015 }
2016 }
2017 FILEDESC_XLOCK(fdp);
2018
2019 /* XXX This should happen earlier. */
2020 mtx_lock(&fdesc_mtx);
2021 td->td_proc->p_fd = NULL;
2022 mtx_unlock(&fdesc_mtx);
2023
2024 if (fdp->fd_nfiles > NDFILE)
2025 free(fdp->fd_ofiles, M_FILEDESC);
2026 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE))
2027 free(fdp->fd_map, M_FILEDESC);
2028
2029 fdp->fd_nfiles = 0;
2030
2031 cdir = fdp->fd_cdir;
2032 fdp->fd_cdir = NULL;
2033 rdir = fdp->fd_rdir;
2034 fdp->fd_rdir = NULL;
2035 jdir = fdp->fd_jdir;
2036 fdp->fd_jdir = NULL;
2037 FILEDESC_XUNLOCK(fdp);
2038
2039 if (cdir) {
2040 locked = VFS_LOCK_GIANT(cdir->v_mount);
2041 vrele(cdir);
2042 VFS_UNLOCK_GIANT(locked);
2043 }
2044 if (rdir) {
2045 locked = VFS_LOCK_GIANT(rdir->v_mount);
2046 vrele(rdir);
2047 VFS_UNLOCK_GIANT(locked);
2048 }
2049 if (jdir) {
2050 locked = VFS_LOCK_GIANT(jdir->v_mount);
2051 vrele(jdir);
2052 VFS_UNLOCK_GIANT(locked);
2053 }
2054
2055 fddrop(fdp);
2056 }
2057
2058 /*
2059 * For setugid programs, we don't want to people to use that setugidness
2060 * to generate error messages which write to a file which otherwise would
2061 * otherwise be off-limits to the process. We check for filesystems where
2062 * the vnode can change out from under us after execve (like [lin]procfs).
2063 *
2064 * Since setugidsafety calls this only for fd 0, 1 and 2, this check is
2065 * sufficient. We also don't check for setugidness since we know we are.
2066 */
2067 static int
2068 is_unsafe(struct file *fp)
2069 {
2070 if (fp->f_type == DTYPE_VNODE) {
2071 struct vnode *vp = fp->f_vnode;
2072
2073 if ((vp->v_vflag & VV_PROCDEP) != 0)
2074 return (1);
2075 }
2076 return (0);
2077 }
2078
2079 /*
2080 * Make this setguid thing safe, if at all possible.
2081 */
2082 void
2083 setugidsafety(struct thread *td)
2084 {
2085 struct filedesc *fdp;
2086 int i;
2087
2088 /* Certain daemons might not have file descriptors. */
2089 fdp = td->td_proc->p_fd;
2090 if (fdp == NULL)
2091 return;
2092
2093 /*
2094 * Note: fdp->fd_ofiles may be reallocated out from under us while
2095 * we are blocked in a close. Be careful!
2096 */
2097 FILEDESC_XLOCK(fdp);
2098 for (i = 0; i <= fdp->fd_lastfile; i++) {
2099 if (i > 2)
2100 break;
2101 if (fdp->fd_ofiles[i] && is_unsafe(fdp->fd_ofiles[i])) {
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 FILEDESC_XUNLOCK(fdp);
2114 (void) closef(fp, td);
2115 FILEDESC_XLOCK(fdp);
2116 }
2117 }
2118 FILEDESC_XUNLOCK(fdp);
2119 }
2120
2121 /*
2122 * If a specific file object occupies a specific file descriptor, close the
2123 * file descriptor entry and drop a reference on the file object. This is a
2124 * convenience function to handle a subsequent error in a function that calls
2125 * falloc() that handles the race that another thread might have closed the
2126 * file descriptor out from under the thread creating the file object.
2127 */
2128 void
2129 fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td)
2130 {
2131
2132 FILEDESC_XLOCK(fdp);
2133 if (fdp->fd_ofiles[idx] == fp) {
2134 fdp->fd_ofiles[idx] = NULL;
2135 fdunused(fdp, idx);
2136 FILEDESC_XUNLOCK(fdp);
2137 fdrop(fp, td);
2138 } else
2139 FILEDESC_XUNLOCK(fdp);
2140 }
2141
2142 /*
2143 * Close any files on exec?
2144 */
2145 void
2146 fdcloseexec(struct thread *td)
2147 {
2148 struct filedesc *fdp;
2149 int i;
2150
2151 /* Certain daemons might not have file descriptors. */
2152 fdp = td->td_proc->p_fd;
2153 if (fdp == NULL)
2154 return;
2155
2156 FILEDESC_XLOCK(fdp);
2157
2158 /*
2159 * We cannot cache fd_ofiles or fd_ofileflags since operations
2160 * may block and rip them out from under us.
2161 */
2162 for (i = 0; i <= fdp->fd_lastfile; i++) {
2163 if (fdp->fd_ofiles[i] != NULL &&
2164 (fdp->fd_ofiles[i]->f_type == DTYPE_MQUEUE ||
2165 (fdp->fd_ofileflags[i] & UF_EXCLOSE))) {
2166 struct file *fp;
2167
2168 knote_fdclose(td, i);
2169 /*
2170 * NULL-out descriptor prior to close to avoid
2171 * a race while close blocks.
2172 */
2173 fp = fdp->fd_ofiles[i];
2174 fdp->fd_ofiles[i] = NULL;
2175 fdp->fd_ofileflags[i] = 0;
2176 fdunused(fdp, i);
2177 if (fp->f_type == DTYPE_MQUEUE)
2178 mq_fdclose(td, i, fp);
2179 FILEDESC_XUNLOCK(fdp);
2180 (void) closef(fp, td);
2181 FILEDESC_XLOCK(fdp);
2182 }
2183 }
2184 FILEDESC_XUNLOCK(fdp);
2185 }
2186
2187 /*
2188 * It is unsafe for set[ug]id processes to be started with file
2189 * descriptors 0..2 closed, as these descriptors are given implicit
2190 * significance in the Standard C library. fdcheckstd() will create a
2191 * descriptor referencing /dev/null for each of stdin, stdout, and
2192 * stderr that is not already open.
2193 */
2194 int
2195 fdcheckstd(struct thread *td)
2196 {
2197 struct filedesc *fdp;
2198 register_t retval, save;
2199 int i, error, devnull;
2200
2201 fdp = td->td_proc->p_fd;
2202 if (fdp == NULL)
2203 return (0);
2204 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2205 devnull = -1;
2206 error = 0;
2207 for (i = 0; i < 3; i++) {
2208 if (fdp->fd_ofiles[i] != NULL)
2209 continue;
2210 if (devnull < 0) {
2211 save = td->td_retval[0];
2212 error = kern_open(td, "/dev/null", UIO_SYSSPACE,
2213 O_RDWR, 0);
2214 devnull = td->td_retval[0];
2215 td->td_retval[0] = save;
2216 if (error)
2217 break;
2218 KASSERT(devnull == i, ("oof, we didn't get our fd"));
2219 } else {
2220 error = do_dup(td, DUP_FIXED, devnull, i, &retval);
2221 if (error != 0)
2222 break;
2223 }
2224 }
2225 return (error);
2226 }
2227
2228 /*
2229 * Internal form of close. Decrement reference count on file structure.
2230 * Note: td may be NULL when closing a file that was being passed in a
2231 * message.
2232 *
2233 * XXXRW: Giant is not required for the caller, but often will be held; this
2234 * makes it moderately likely the Giant will be recursed in the VFS case.
2235 */
2236 int
2237 closef(struct file *fp, struct thread *td)
2238 {
2239 struct vnode *vp;
2240 struct flock lf;
2241 struct filedesc_to_leader *fdtol;
2242 struct filedesc *fdp;
2243 struct file *fp_object;
2244
2245 /*
2246 * POSIX record locking dictates that any close releases ALL
2247 * locks owned by this process. This is handled by setting
2248 * a flag in the unlock to free ONLY locks obeying POSIX
2249 * semantics, and not to free BSD-style file locks.
2250 * If the descriptor was in a message, POSIX-style locks
2251 * aren't passed with the descriptor, and the thread pointer
2252 * will be NULL. Callers should be careful only to pass a
2253 * NULL thread pointer when there really is no owning
2254 * context that might have locks, or the locks will be
2255 * leaked.
2256 *
2257 * If this is a capability, we do lock processing under the underlying
2258 * node, not the capability itself.
2259 */
2260 (void)cap_funwrap(fp, 0, &fp_object);
2261 if ((fp_object->f_type == DTYPE_VNODE) && (td != NULL)) {
2262 int vfslocked;
2263
2264 vp = fp_object->f_vnode;
2265 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
2266 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
2267 lf.l_whence = SEEK_SET;
2268 lf.l_start = 0;
2269 lf.l_len = 0;
2270 lf.l_type = F_UNLCK;
2271 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader,
2272 F_UNLCK, &lf, F_POSIX);
2273 }
2274 fdtol = td->td_proc->p_fdtol;
2275 if (fdtol != NULL) {
2276 /*
2277 * Handle special case where file descriptor table is
2278 * shared between multiple process leaders.
2279 */
2280 fdp = td->td_proc->p_fd;
2281 FILEDESC_XLOCK(fdp);
2282 for (fdtol = fdtol->fdl_next;
2283 fdtol != td->td_proc->p_fdtol;
2284 fdtol = fdtol->fdl_next) {
2285 if ((fdtol->fdl_leader->p_flag &
2286 P_ADVLOCK) == 0)
2287 continue;
2288 fdtol->fdl_holdcount++;
2289 FILEDESC_XUNLOCK(fdp);
2290 lf.l_whence = SEEK_SET;
2291 lf.l_start = 0;
2292 lf.l_len = 0;
2293 lf.l_type = F_UNLCK;
2294 vp = fp_object->f_vnode;
2295 (void) VOP_ADVLOCK(vp,
2296 (caddr_t)fdtol->fdl_leader,
2297 F_UNLCK, &lf, F_POSIX);
2298 FILEDESC_XLOCK(fdp);
2299 fdtol->fdl_holdcount--;
2300 if (fdtol->fdl_holdcount == 0 &&
2301 fdtol->fdl_wakeup != 0) {
2302 fdtol->fdl_wakeup = 0;
2303 wakeup(fdtol);
2304 }
2305 }
2306 FILEDESC_XUNLOCK(fdp);
2307 }
2308 VFS_UNLOCK_GIANT(vfslocked);
2309 }
2310 return (fdrop(fp, td));
2311 }
2312
2313 /*
2314 * Initialize the file pointer with the specified properties.
2315 *
2316 * The ops are set with release semantics to be certain that the flags, type,
2317 * and data are visible when ops is. This is to prevent ops methods from being
2318 * called with bad data.
2319 */
2320 void
2321 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops)
2322 {
2323 fp->f_data = data;
2324 fp->f_flag = flag;
2325 fp->f_type = type;
2326 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops);
2327 }
2328
2329 struct file *
2330 fget_unlocked(struct filedesc *fdp, int fd)
2331 {
2332 struct file *fp;
2333 u_int count;
2334
2335 if (fd < 0 || fd >= fdp->fd_nfiles)
2336 return (NULL);
2337 /*
2338 * Fetch the descriptor locklessly. We avoid fdrop() races by
2339 * never raising a refcount above 0. To accomplish this we have
2340 * to use a cmpset loop rather than an atomic_add. The descriptor
2341 * must be re-verified once we acquire a reference to be certain
2342 * that the identity is still correct and we did not lose a race
2343 * due to preemption.
2344 */
2345 for (;;) {
2346 fp = fdp->fd_ofiles[fd];
2347 if (fp == NULL)
2348 break;
2349 count = fp->f_count;
2350 if (count == 0)
2351 continue;
2352 /*
2353 * Use an acquire barrier to prevent caching of fd_ofiles
2354 * so it is refreshed for verification.
2355 */
2356 if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1)
2357 continue;
2358 if (fp == fdp->fd_ofiles[fd])
2359 break;
2360 fdrop(fp, curthread);
2361 }
2362
2363 return (fp);
2364 }
2365
2366 /*
2367 * Extract the file pointer associated with the specified descriptor for the
2368 * current user process.
2369 *
2370 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is
2371 * returned.
2372 *
2373 * If the FGET_GETCAP flag is set, the capability itself will be returned.
2374 * Calling _fget() with FGET_GETCAP on a non-capability will return EINVAL.
2375 * Otherwise, if the file is a capability, its rights will be checked against
2376 * the capability rights mask, and if successful, the object will be unwrapped.
2377 *
2378 * If an error occured the non-zero error is returned and *fpp is set to
2379 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is
2380 * responsible for fdrop().
2381 */
2382 #define FGET_GETCAP 0x00000001
2383 static __inline int
2384 _fget(struct thread *td, int fd, struct file **fpp, int flags,
2385 cap_rights_t needrights, cap_rights_t *haverightsp, u_char *maxprotp,
2386 int fget_flags)
2387 {
2388 struct filedesc *fdp;
2389 struct file *fp;
2390 #ifdef CAPABILITIES
2391 struct file *fp_fromcap;
2392 #endif
2393 int error;
2394
2395 *fpp = NULL;
2396 if (td == NULL || (fdp = td->td_proc->p_fd) == NULL)
2397 return (EBADF);
2398 if ((fp = fget_unlocked(fdp, fd)) == NULL)
2399 return (EBADF);
2400 if (fp->f_ops == &badfileops) {
2401 fdrop(fp, td);
2402 return (EBADF);
2403 }
2404
2405 #ifdef CAPABILITIES
2406 /*
2407 * If this is a capability, what rights does it have?
2408 */
2409 if (haverightsp != NULL) {
2410 if (fp->f_type == DTYPE_CAPABILITY)
2411 *haverightsp = cap_rights(fp);
2412 else
2413 *haverightsp = CAP_MASK_VALID;
2414 }
2415
2416 /*
2417 * If a capability has been requested, return the capability directly.
2418 * Otherwise, check capability rights, extract the underlying object,
2419 * and check its access flags.
2420 */
2421 if (fget_flags & FGET_GETCAP) {
2422 if (fp->f_type != DTYPE_CAPABILITY) {
2423 fdrop(fp, td);
2424 return (EINVAL);
2425 }
2426 } else {
2427 if (maxprotp == NULL)
2428 error = cap_funwrap(fp, needrights, &fp_fromcap);
2429 else
2430 error = cap_funwrap_mmap(fp, needrights, maxprotp,
2431 &fp_fromcap);
2432 if (error != 0) {
2433 fdrop(fp, td);
2434 return (error);
2435 }
2436
2437 /*
2438 * If we've unwrapped a file, drop the original capability
2439 * and hold the new descriptor. fp after this point refers to
2440 * the actual (unwrapped) object, not the capability.
2441 */
2442 if (fp != fp_fromcap) {
2443 fhold(fp_fromcap);
2444 fdrop(fp, td);
2445 fp = fp_fromcap;
2446 }
2447 }
2448 #else /* !CAPABILITIES */
2449 KASSERT(fp->f_type != DTYPE_CAPABILITY,
2450 ("%s: saw capability", __func__));
2451 if (maxprotp != NULL)
2452 *maxprotp = VM_PROT_ALL;
2453 #endif /* CAPABILITIES */
2454
2455 /*
2456 * FREAD and FWRITE failure return EBADF as per POSIX.
2457 */
2458 error = 0;
2459 switch (flags) {
2460 case FREAD:
2461 case FWRITE:
2462 if ((fp->f_flag & flags) == 0)
2463 error = EBADF;
2464 break;
2465 case FEXEC:
2466 if ((fp->f_flag & (FREAD | FEXEC)) == 0 ||
2467 ((fp->f_flag & FWRITE) != 0))
2468 error = EBADF;
2469 break;
2470 case 0:
2471 break;
2472 default:
2473 KASSERT(0, ("wrong flags"));
2474 }
2475
2476 if (error != 0) {
2477 fdrop(fp, td);
2478 return (error);
2479 }
2480
2481 *fpp = fp;
2482 return (0);
2483 }
2484
2485 int
2486 fget(struct thread *td, int fd, cap_rights_t rights, struct file **fpp)
2487 {
2488
2489 return(_fget(td, fd, fpp, 0, rights, NULL, NULL, 0));
2490 }
2491
2492 int
2493 fget_mmap(struct thread *td, int fd, cap_rights_t rights, u_char *maxprotp,
2494 struct file **fpp)
2495 {
2496
2497 return (_fget(td, fd, fpp, 0, rights, NULL, maxprotp, 0));
2498 }
2499
2500 int
2501 fget_read(struct thread *td, int fd, cap_rights_t rights, struct file **fpp)
2502 {
2503
2504 return(_fget(td, fd, fpp, FREAD, rights, NULL, NULL, 0));
2505 }
2506
2507 int
2508 fget_write(struct thread *td, int fd, cap_rights_t rights, struct file **fpp)
2509 {
2510
2511 return (_fget(td, fd, fpp, FWRITE, rights, NULL, NULL, 0));
2512 }
2513
2514 /*
2515 * Unlike the other fget() calls, which accept and check capability rights
2516 * but never return capabilities, fgetcap() returns the capability but doesn't
2517 * check capability rights.
2518 */
2519 int
2520 fgetcap(struct thread *td, int fd, struct file **fpp)
2521 {
2522
2523 return (_fget(td, fd, fpp, 0, 0, NULL, NULL, FGET_GETCAP));
2524 }
2525
2526
2527 /*
2528 * Like fget() but loads the underlying vnode, or returns an error if the
2529 * descriptor does not represent a vnode. Note that pipes use vnodes but
2530 * never have VM objects. The returned vnode will be vref()'d.
2531 *
2532 * XXX: what about the unused flags ?
2533 */
2534 static __inline int
2535 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t needrights,
2536 cap_rights_t *haverightsp, struct vnode **vpp)
2537 {
2538 struct file *fp;
2539 int error;
2540
2541 *vpp = NULL;
2542 if ((error = _fget(td, fd, &fp, flags, needrights, haverightsp,
2543 NULL, 0)) != 0)
2544 return (error);
2545 if (fp->f_vnode == NULL) {
2546 error = EINVAL;
2547 } else {
2548 *vpp = fp->f_vnode;
2549 vref(*vpp);
2550 }
2551 fdrop(fp, td);
2552
2553 return (error);
2554 }
2555
2556 int
2557 fgetvp(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp)
2558 {
2559
2560 return (_fgetvp(td, fd, 0, rights, NULL, vpp));
2561 }
2562
2563 int
2564 fgetvp_rights(struct thread *td, int fd, cap_rights_t need, cap_rights_t *have,
2565 struct vnode **vpp)
2566 {
2567 return (_fgetvp(td, fd, 0, need, have, vpp));
2568 }
2569
2570 int
2571 fgetvp_read(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp)
2572 {
2573
2574 return (_fgetvp(td, fd, FREAD, rights, NULL, vpp));
2575 }
2576
2577 int
2578 fgetvp_exec(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp)
2579 {
2580
2581 return (_fgetvp(td, fd, FEXEC, rights, NULL, vpp));
2582 }
2583
2584 #ifdef notyet
2585 int
2586 fgetvp_write(struct thread *td, int fd, cap_rights_t rights,
2587 struct vnode **vpp)
2588 {
2589
2590 return (_fgetvp(td, fd, FWRITE, rights, NULL, vpp));
2591 }
2592 #endif
2593
2594 /*
2595 * Like fget() but loads the underlying socket, or returns an error if the
2596 * descriptor does not represent a socket.
2597 *
2598 * We bump the ref count on the returned socket. XXX Also obtain the SX lock
2599 * in the future.
2600 *
2601 * Note: fgetsock() and fputsock() are deprecated, as consumers should rely
2602 * on their file descriptor reference to prevent the socket from being free'd
2603 * during use.
2604 */
2605 int
2606 fgetsock(struct thread *td, int fd, cap_rights_t rights, struct socket **spp,
2607 u_int *fflagp)
2608 {
2609 struct file *fp;
2610 int error;
2611
2612 *spp = NULL;
2613 if (fflagp != NULL)
2614 *fflagp = 0;
2615 if ((error = _fget(td, fd, &fp, 0, rights, NULL, NULL, 0)) != 0)
2616 return (error);
2617 if (fp->f_type != DTYPE_SOCKET) {
2618 error = ENOTSOCK;
2619 } else {
2620 *spp = fp->f_data;
2621 if (fflagp)
2622 *fflagp = fp->f_flag;
2623 SOCK_LOCK(*spp);
2624 soref(*spp);
2625 SOCK_UNLOCK(*spp);
2626 }
2627 fdrop(fp, td);
2628
2629 return (error);
2630 }
2631
2632 /*
2633 * Drop the reference count on the socket and XXX release the SX lock in the
2634 * future. The last reference closes the socket.
2635 *
2636 * Note: fputsock() is deprecated, see comment for fgetsock().
2637 */
2638 void
2639 fputsock(struct socket *so)
2640 {
2641
2642 ACCEPT_LOCK();
2643 SOCK_LOCK(so);
2644 CURVNET_SET(so->so_vnet);
2645 sorele(so);
2646 CURVNET_RESTORE();
2647 }
2648
2649 /*
2650 * Handle the last reference to a file being closed.
2651 *
2652 * No special capability handling here, as the capability's fo_close will run
2653 * instead of the object here, and perform any necessary drop on the object.
2654 */
2655 int
2656 _fdrop(struct file *fp, struct thread *td)
2657 {
2658 int error;
2659
2660 error = 0;
2661 if (fp->f_count != 0)
2662 panic("fdrop: count %d", fp->f_count);
2663 if (fp->f_ops != &badfileops)
2664 error = fo_close(fp, td);
2665 atomic_subtract_int(&openfiles, 1);
2666 crfree(fp->f_cred);
2667 free(fp->f_advice, M_FADVISE);
2668 uma_zfree(file_zone, fp);
2669
2670 return (error);
2671 }
2672
2673 /*
2674 * Apply an advisory lock on a file descriptor.
2675 *
2676 * Just attempt to get a record lock of the requested type on the entire file
2677 * (l_whence = SEEK_SET, l_start = 0, l_len = 0).
2678 */
2679 #ifndef _SYS_SYSPROTO_H_
2680 struct flock_args {
2681 int fd;
2682 int how;
2683 };
2684 #endif
2685 /* ARGSUSED */
2686 int
2687 sys_flock(struct thread *td, struct flock_args *uap)
2688 {
2689 struct file *fp;
2690 struct vnode *vp;
2691 struct flock lf;
2692 int vfslocked;
2693 int error;
2694
2695 if ((error = fget(td, uap->fd, CAP_FLOCK, &fp)) != 0)
2696 return (error);
2697 if (fp->f_type != DTYPE_VNODE) {
2698 fdrop(fp, td);
2699 return (EOPNOTSUPP);
2700 }
2701
2702 vp = fp->f_vnode;
2703 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
2704 lf.l_whence = SEEK_SET;
2705 lf.l_start = 0;
2706 lf.l_len = 0;
2707 if (uap->how & LOCK_UN) {
2708 lf.l_type = F_UNLCK;
2709 atomic_clear_int(&fp->f_flag, FHASLOCK);
2710 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK);
2711 goto done2;
2712 }
2713 if (uap->how & LOCK_EX)
2714 lf.l_type = F_WRLCK;
2715 else if (uap->how & LOCK_SH)
2716 lf.l_type = F_RDLCK;
2717 else {
2718 error = EBADF;
2719 goto done2;
2720 }
2721 atomic_set_int(&fp->f_flag, FHASLOCK);
2722 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
2723 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT);
2724 done2:
2725 fdrop(fp, td);
2726 VFS_UNLOCK_GIANT(vfslocked);
2727 return (error);
2728 }
2729 /*
2730 * Duplicate the specified descriptor to a free descriptor.
2731 */
2732 int
2733 dupfdopen(struct thread *td, struct filedesc *fdp, int indx, int dfd, int mode, int error)
2734 {
2735 struct file *wfp;
2736 struct file *fp;
2737
2738 /*
2739 * If the to-be-dup'd fd number is greater than the allowed number
2740 * of file descriptors, or the fd to be dup'd has already been
2741 * closed, then reject.
2742 */
2743 FILEDESC_XLOCK(fdp);
2744 if (dfd < 0 || dfd >= fdp->fd_nfiles ||
2745 (wfp = fdp->fd_ofiles[dfd]) == NULL) {
2746 FILEDESC_XUNLOCK(fdp);
2747 return (EBADF);
2748 }
2749
2750 /*
2751 * There are two cases of interest here.
2752 *
2753 * For ENODEV simply dup (dfd) to file descriptor (indx) and return.
2754 *
2755 * For ENXIO steal away the file structure from (dfd) and store it in
2756 * (indx). (dfd) is effectively closed by this operation.
2757 *
2758 * Any other error code is just returned.
2759 */
2760 switch (error) {
2761 case ENODEV:
2762 /*
2763 * Check that the mode the file is being opened for is a
2764 * subset of the mode of the existing descriptor.
2765 */
2766 if (((mode & (FREAD|FWRITE)) | wfp->f_flag) != wfp->f_flag) {
2767 FILEDESC_XUNLOCK(fdp);
2768 return (EACCES);
2769 }
2770 fp = fdp->fd_ofiles[indx];
2771 fdp->fd_ofiles[indx] = wfp;
2772 fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd];
2773 if (fp == NULL)
2774 fdused(fdp, indx);
2775 fhold(wfp);
2776 FILEDESC_XUNLOCK(fdp);
2777 if (fp != NULL)
2778 /*
2779 * We now own the reference to fp that the ofiles[]
2780 * array used to own. Release it.
2781 */
2782 fdrop(fp, td);
2783 return (0);
2784
2785 case ENXIO:
2786 /*
2787 * Steal away the file pointer from dfd and stuff it into indx.
2788 */
2789 fp = fdp->fd_ofiles[indx];
2790 fdp->fd_ofiles[indx] = fdp->fd_ofiles[dfd];
2791 fdp->fd_ofiles[dfd] = NULL;
2792 fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd];
2793 fdp->fd_ofileflags[dfd] = 0;
2794 fdunused(fdp, dfd);
2795 if (fp == NULL)
2796 fdused(fdp, indx);
2797 FILEDESC_XUNLOCK(fdp);
2798
2799 /*
2800 * We now own the reference to fp that the ofiles[] array
2801 * used to own. Release it.
2802 */
2803 if (fp != NULL)
2804 fdrop(fp, td);
2805 return (0);
2806
2807 default:
2808 FILEDESC_XUNLOCK(fdp);
2809 return (error);
2810 }
2811 /* NOTREACHED */
2812 }
2813
2814 /*
2815 * Scan all active processes and prisons to see if any of them have a current
2816 * or root directory of `olddp'. If so, replace them with the new mount point.
2817 */
2818 void
2819 mountcheckdirs(struct vnode *olddp, struct vnode *newdp)
2820 {
2821 struct filedesc *fdp;
2822 struct prison *pr;
2823 struct proc *p;
2824 int nrele;
2825
2826 if (vrefcnt(olddp) == 1)
2827 return;
2828 nrele = 0;
2829 sx_slock(&allproc_lock);
2830 FOREACH_PROC_IN_SYSTEM(p) {
2831 fdp = fdhold(p);
2832 if (fdp == NULL)
2833 continue;
2834 FILEDESC_XLOCK(fdp);
2835 if (fdp->fd_cdir == olddp) {
2836 vref(newdp);
2837 fdp->fd_cdir = newdp;
2838 nrele++;
2839 }
2840 if (fdp->fd_rdir == olddp) {
2841 vref(newdp);
2842 fdp->fd_rdir = newdp;
2843 nrele++;
2844 }
2845 if (fdp->fd_jdir == olddp) {
2846 vref(newdp);
2847 fdp->fd_jdir = newdp;
2848 nrele++;
2849 }
2850 FILEDESC_XUNLOCK(fdp);
2851 fddrop(fdp);
2852 }
2853 sx_sunlock(&allproc_lock);
2854 if (rootvnode == olddp) {
2855 vref(newdp);
2856 rootvnode = newdp;
2857 nrele++;
2858 }
2859 mtx_lock(&prison0.pr_mtx);
2860 if (prison0.pr_root == olddp) {
2861 vref(newdp);
2862 prison0.pr_root = newdp;
2863 nrele++;
2864 }
2865 mtx_unlock(&prison0.pr_mtx);
2866 sx_slock(&allprison_lock);
2867 TAILQ_FOREACH(pr, &allprison, pr_list) {
2868 mtx_lock(&pr->pr_mtx);
2869 if (pr->pr_root == olddp) {
2870 vref(newdp);
2871 pr->pr_root = newdp;
2872 nrele++;
2873 }
2874 mtx_unlock(&pr->pr_mtx);
2875 }
2876 sx_sunlock(&allprison_lock);
2877 while (nrele--)
2878 vrele(olddp);
2879 }
2880
2881 struct filedesc_to_leader *
2882 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader)
2883 {
2884 struct filedesc_to_leader *fdtol;
2885
2886 fdtol = malloc(sizeof(struct filedesc_to_leader),
2887 M_FILEDESC_TO_LEADER,
2888 M_WAITOK);
2889 fdtol->fdl_refcount = 1;
2890 fdtol->fdl_holdcount = 0;
2891 fdtol->fdl_wakeup = 0;
2892 fdtol->fdl_leader = leader;
2893 if (old != NULL) {
2894 FILEDESC_XLOCK(fdp);
2895 fdtol->fdl_next = old->fdl_next;
2896 fdtol->fdl_prev = old;
2897 old->fdl_next = fdtol;
2898 fdtol->fdl_next->fdl_prev = fdtol;
2899 FILEDESC_XUNLOCK(fdp);
2900 } else {
2901 fdtol->fdl_next = fdtol;
2902 fdtol->fdl_prev = fdtol;
2903 }
2904 return (fdtol);
2905 }
2906
2907 /*
2908 * Get file structures globally.
2909 */
2910 static int
2911 sysctl_kern_file(SYSCTL_HANDLER_ARGS)
2912 {
2913 struct xfile xf;
2914 struct filedesc *fdp;
2915 struct file *fp;
2916 struct proc *p;
2917 int error, n;
2918
2919 error = sysctl_wire_old_buffer(req, 0);
2920 if (error != 0)
2921 return (error);
2922 if (req->oldptr == NULL) {
2923 n = 0;
2924 sx_slock(&allproc_lock);
2925 FOREACH_PROC_IN_SYSTEM(p) {
2926 if (p->p_state == PRS_NEW)
2927 continue;
2928 fdp = fdhold(p);
2929 if (fdp == NULL)
2930 continue;
2931 /* overestimates sparse tables. */
2932 if (fdp->fd_lastfile > 0)
2933 n += fdp->fd_lastfile;
2934 fddrop(fdp);
2935 }
2936 sx_sunlock(&allproc_lock);
2937 return (SYSCTL_OUT(req, 0, n * sizeof(xf)));
2938 }
2939 error = 0;
2940 bzero(&xf, sizeof(xf));
2941 xf.xf_size = sizeof(xf);
2942 sx_slock(&allproc_lock);
2943 FOREACH_PROC_IN_SYSTEM(p) {
2944 PROC_LOCK(p);
2945 if (p->p_state == PRS_NEW) {
2946 PROC_UNLOCK(p);
2947 continue;
2948 }
2949 if (p_cansee(req->td, p) != 0) {
2950 PROC_UNLOCK(p);
2951 continue;
2952 }
2953 xf.xf_pid = p->p_pid;
2954 xf.xf_uid = p->p_ucred->cr_uid;
2955 PROC_UNLOCK(p);
2956 fdp = fdhold(p);
2957 if (fdp == NULL)
2958 continue;
2959 FILEDESC_SLOCK(fdp);
2960 for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) {
2961 if ((fp = fdp->fd_ofiles[n]) == NULL)
2962 continue;
2963 xf.xf_fd = n;
2964 xf.xf_file = fp;
2965 xf.xf_data = fp->f_data;
2966 xf.xf_vnode = fp->f_vnode;
2967 xf.xf_type = fp->f_type;
2968 xf.xf_count = fp->f_count;
2969 xf.xf_msgcount = 0;
2970 xf.xf_offset = foffset_get(fp);
2971 xf.xf_flag = fp->f_flag;
2972 error = SYSCTL_OUT(req, &xf, sizeof(xf));
2973 if (error)
2974 break;
2975 }
2976 FILEDESC_SUNLOCK(fdp);
2977 fddrop(fdp);
2978 if (error)
2979 break;
2980 }
2981 sx_sunlock(&allproc_lock);
2982 return (error);
2983 }
2984
2985 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD,
2986 0, 0, sysctl_kern_file, "S,xfile", "Entire file table");
2987
2988 #ifdef KINFO_OFILE_SIZE
2989 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE);
2990 #endif
2991
2992 #ifdef COMPAT_FREEBSD7
2993 static int
2994 export_vnode_for_osysctl(struct vnode *vp, int type,
2995 struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req)
2996 {
2997 int error;
2998 char *fullpath, *freepath;
2999 int vfslocked;
3000
3001 bzero(kif, sizeof(*kif));
3002 kif->kf_structsize = sizeof(*kif);
3003
3004 vref(vp);
3005 kif->kf_fd = type;
3006 kif->kf_type = KF_TYPE_VNODE;
3007 /* This function only handles directories. */
3008 if (vp->v_type != VDIR) {
3009 vrele(vp);
3010 return (ENOTDIR);
3011 }
3012 kif->kf_vnode_type = KF_VTYPE_VDIR;
3013
3014 /*
3015 * This is not a true file descriptor, so we set a bogus refcount
3016 * and offset to indicate these fields should be ignored.
3017 */
3018 kif->kf_ref_count = -1;
3019 kif->kf_offset = -1;
3020
3021 freepath = NULL;
3022 fullpath = "-";
3023 FILEDESC_SUNLOCK(fdp);
3024 vn_fullpath(curthread, vp, &fullpath, &freepath);
3025 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3026 vrele(vp);
3027 VFS_UNLOCK_GIANT(vfslocked);
3028 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
3029 if (freepath != NULL)
3030 free(freepath, M_TEMP);
3031 error = SYSCTL_OUT(req, kif, sizeof(*kif));
3032 FILEDESC_SLOCK(fdp);
3033 return (error);
3034 }
3035
3036 /*
3037 * Get per-process file descriptors for use by procstat(1), et al.
3038 */
3039 static int
3040 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS)
3041 {
3042 char *fullpath, *freepath;
3043 struct kinfo_ofile *kif;
3044 struct filedesc *fdp;
3045 int error, i, *name;
3046 struct shmfd *shmfd;
3047 struct socket *so;
3048 struct vnode *vp;
3049 struct ksem *ks;
3050 struct file *fp;
3051 struct proc *p;
3052 struct tty *tp;
3053 int vfslocked;
3054
3055 name = (int *)arg1;
3056 error = pget((pid_t)name[0], PGET_CANDEBUG, &p);
3057 if (error != 0)
3058 return (error);
3059 fdp = fdhold(p);
3060 PROC_UNLOCK(p);
3061 if (fdp == NULL)
3062 return (ENOENT);
3063 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK);
3064 FILEDESC_SLOCK(fdp);
3065 if (fdp->fd_cdir != NULL)
3066 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif,
3067 fdp, req);
3068 if (fdp->fd_rdir != NULL)
3069 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif,
3070 fdp, req);
3071 if (fdp->fd_jdir != NULL)
3072 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif,
3073 fdp, req);
3074 for (i = 0; i < fdp->fd_nfiles; i++) {
3075 if ((fp = fdp->fd_ofiles[i]) == NULL)
3076 continue;
3077 bzero(kif, sizeof(*kif));
3078 kif->kf_structsize = sizeof(*kif);
3079 ks = NULL;
3080 vp = NULL;
3081 so = NULL;
3082 tp = NULL;
3083 shmfd = NULL;
3084 kif->kf_fd = i;
3085
3086 #ifdef CAPABILITIES
3087 /*
3088 * When reporting a capability, most fields will be from the
3089 * underlying object, but do mark as a capability. With
3090 * ofiledesc, we don't have a field to export the cap_rights_t,
3091 * but we do with the new filedesc.
3092 */
3093 if (fp->f_type == DTYPE_CAPABILITY) {
3094 kif->kf_flags |= KF_FLAG_CAPABILITY;
3095 (void)cap_funwrap(fp, 0, &fp);
3096 }
3097 #else
3098 KASSERT(fp->f_type != DTYPE_CAPABILITY,
3099 ("sysctl_kern_proc_ofiledesc: saw capability"));
3100 #endif
3101 switch (fp->f_type) {
3102 case DTYPE_VNODE:
3103 kif->kf_type = KF_TYPE_VNODE;
3104 vp = fp->f_vnode;
3105 break;
3106
3107 case DTYPE_SOCKET:
3108 kif->kf_type = KF_TYPE_SOCKET;
3109 so = fp->f_data;
3110 break;
3111
3112 case DTYPE_PIPE:
3113 kif->kf_type = KF_TYPE_PIPE;
3114 break;
3115
3116 case DTYPE_FIFO:
3117 kif->kf_type = KF_TYPE_FIFO;
3118 vp = fp->f_vnode;
3119 break;
3120
3121 case DTYPE_KQUEUE:
3122 kif->kf_type = KF_TYPE_KQUEUE;
3123 break;
3124
3125 case DTYPE_CRYPTO:
3126 kif->kf_type = KF_TYPE_CRYPTO;
3127 break;
3128
3129 case DTYPE_MQUEUE:
3130 kif->kf_type = KF_TYPE_MQUEUE;
3131 break;
3132
3133 case DTYPE_SHM:
3134 kif->kf_type = KF_TYPE_SHM;
3135 shmfd = fp->f_data;
3136 break;
3137
3138 case DTYPE_SEM:
3139 kif->kf_type = KF_TYPE_SEM;
3140 ks = fp->f_data;
3141 break;
3142
3143 case DTYPE_PTS:
3144 kif->kf_type = KF_TYPE_PTS;
3145 tp = fp->f_data;
3146 break;
3147
3148 #ifdef PROCDESC
3149 case DTYPE_PROCDESC:
3150 kif->kf_type = KF_TYPE_PROCDESC;
3151 break;
3152 #endif
3153
3154 default:
3155 kif->kf_type = KF_TYPE_UNKNOWN;
3156 break;
3157 }
3158 kif->kf_ref_count = fp->f_count;
3159 if (fp->f_flag & FREAD)
3160 kif->kf_flags |= KF_FLAG_READ;
3161 if (fp->f_flag & FWRITE)
3162 kif->kf_flags |= KF_FLAG_WRITE;
3163 if (fp->f_flag & FAPPEND)
3164 kif->kf_flags |= KF_FLAG_APPEND;
3165 if (fp->f_flag & FASYNC)
3166 kif->kf_flags |= KF_FLAG_ASYNC;
3167 if (fp->f_flag & FFSYNC)
3168 kif->kf_flags |= KF_FLAG_FSYNC;
3169 if (fp->f_flag & FNONBLOCK)
3170 kif->kf_flags |= KF_FLAG_NONBLOCK;
3171 if (fp->f_flag & O_DIRECT)
3172 kif->kf_flags |= KF_FLAG_DIRECT;
3173 if (fp->f_flag & FHASLOCK)
3174 kif->kf_flags |= KF_FLAG_HASLOCK;
3175 kif->kf_offset = foffset_get(fp);
3176 if (vp != NULL) {
3177 vref(vp);
3178 switch (vp->v_type) {
3179 case VNON:
3180 kif->kf_vnode_type = KF_VTYPE_VNON;
3181 break;
3182 case VREG:
3183 kif->kf_vnode_type = KF_VTYPE_VREG;
3184 break;
3185 case VDIR:
3186 kif->kf_vnode_type = KF_VTYPE_VDIR;
3187 break;
3188 case VBLK:
3189 kif->kf_vnode_type = KF_VTYPE_VBLK;
3190 break;
3191 case VCHR:
3192 kif->kf_vnode_type = KF_VTYPE_VCHR;
3193 break;
3194 case VLNK:
3195 kif->kf_vnode_type = KF_VTYPE_VLNK;
3196 break;
3197 case VSOCK:
3198 kif->kf_vnode_type = KF_VTYPE_VSOCK;
3199 break;
3200 case VFIFO:
3201 kif->kf_vnode_type = KF_VTYPE_VFIFO;
3202 break;
3203 case VBAD:
3204 kif->kf_vnode_type = KF_VTYPE_VBAD;
3205 break;
3206 default:
3207 kif->kf_vnode_type = KF_VTYPE_UNKNOWN;
3208 break;
3209 }
3210 /*
3211 * It is OK to drop the filedesc lock here as we will
3212 * re-validate and re-evaluate its properties when
3213 * the loop continues.
3214 */
3215 freepath = NULL;
3216 fullpath = "-";
3217 FILEDESC_SUNLOCK(fdp);
3218 vn_fullpath(curthread, vp, &fullpath, &freepath);
3219 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3220 vrele(vp);
3221 VFS_UNLOCK_GIANT(vfslocked);
3222 strlcpy(kif->kf_path, fullpath,
3223 sizeof(kif->kf_path));
3224 if (freepath != NULL)
3225 free(freepath, M_TEMP);
3226 FILEDESC_SLOCK(fdp);
3227 }
3228 if (so != NULL) {
3229 struct sockaddr *sa;
3230
3231 if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa)
3232 == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) {
3233 bcopy(sa, &kif->kf_sa_local, sa->sa_len);
3234 free(sa, M_SONAME);
3235 }
3236 if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa)
3237 == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) {
3238 bcopy(sa, &kif->kf_sa_peer, sa->sa_len);
3239 free(sa, M_SONAME);
3240 }
3241 kif->kf_sock_domain =
3242 so->so_proto->pr_domain->dom_family;
3243 kif->kf_sock_type = so->so_type;
3244 kif->kf_sock_protocol = so->so_proto->pr_protocol;
3245 }
3246 if (tp != NULL) {
3247 strlcpy(kif->kf_path, tty_devname(tp),
3248 sizeof(kif->kf_path));
3249 }
3250 if (shmfd != NULL)
3251 shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path));
3252 if (ks != NULL && ksem_info != NULL)
3253 ksem_info(ks, kif->kf_path, sizeof(kif->kf_path), NULL);
3254 error = SYSCTL_OUT(req, kif, sizeof(*kif));
3255 if (error)
3256 break;
3257 }
3258 FILEDESC_SUNLOCK(fdp);
3259 fddrop(fdp);
3260 free(kif, M_TEMP);
3261 return (0);
3262 }
3263
3264 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD,
3265 sysctl_kern_proc_ofiledesc, "Process ofiledesc entries");
3266 #endif /* COMPAT_FREEBSD7 */
3267
3268 #ifdef KINFO_FILE_SIZE
3269 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
3270 #endif
3271
3272 struct export_fd_buf {
3273 struct filedesc *fdp;
3274 struct sbuf *sb;
3275 ssize_t remainder;
3276 struct kinfo_file kif;
3277 };
3278
3279 static int
3280 export_fd_to_sb(void *data, int type, int fd, int fflags, int refcnt,
3281 int64_t offset, int fd_is_cap, cap_rights_t fd_cap_rights,
3282 struct export_fd_buf *efbuf)
3283 {
3284 struct {
3285 int fflag;
3286 int kf_fflag;
3287 } fflags_table[] = {
3288 { FAPPEND, KF_FLAG_APPEND },
3289 { FASYNC, KF_FLAG_ASYNC },
3290 { FFSYNC, KF_FLAG_FSYNC },
3291 { FHASLOCK, KF_FLAG_HASLOCK },
3292 { FNONBLOCK, KF_FLAG_NONBLOCK },
3293 { FREAD, KF_FLAG_READ },
3294 { FWRITE, KF_FLAG_WRITE },
3295 { O_CREAT, KF_FLAG_CREAT },
3296 { O_DIRECT, KF_FLAG_DIRECT },
3297 { O_EXCL, KF_FLAG_EXCL },
3298 { O_EXEC, KF_FLAG_EXEC },
3299 { O_EXLOCK, KF_FLAG_EXLOCK },
3300 { O_NOFOLLOW, KF_FLAG_NOFOLLOW },
3301 { O_SHLOCK, KF_FLAG_SHLOCK },
3302 { O_TRUNC, KF_FLAG_TRUNC }
3303 };
3304 #define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table))
3305 struct kinfo_file *kif;
3306 struct vnode *vp;
3307 int error, locked, vfslocked;
3308 unsigned int i;
3309
3310 if (efbuf->remainder == 0)
3311 return (0);
3312 kif = &efbuf->kif;
3313 bzero(kif, sizeof(*kif));
3314 locked = efbuf->fdp != NULL;
3315 switch (type) {
3316 case KF_TYPE_FIFO:
3317 case KF_TYPE_VNODE:
3318 if (locked) {
3319 FILEDESC_SUNLOCK(efbuf->fdp);
3320 locked = 0;
3321 }
3322 vp = (struct vnode *)data;
3323 error = fill_vnode_info(vp, kif);
3324 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3325 vrele(vp);
3326 VFS_UNLOCK_GIANT(vfslocked);
3327 break;
3328 case KF_TYPE_SOCKET:
3329 error = fill_socket_info((struct socket *)data, kif);
3330 break;
3331 case KF_TYPE_PIPE:
3332 error = fill_pipe_info((struct pipe *)data, kif);
3333 break;
3334 case KF_TYPE_PTS:
3335 error = fill_pts_info((struct tty *)data, kif);
3336 break;
3337 case KF_TYPE_PROCDESC:
3338 error = fill_procdesc_info((struct procdesc *)data, kif);
3339 break;
3340 case KF_TYPE_SEM:
3341 error = fill_sem_info((struct file *)data, kif);
3342 break;
3343 case KF_TYPE_SHM:
3344 error = fill_shm_info((struct file *)data, kif);
3345 break;
3346 default:
3347 error = 0;
3348 }
3349 if (error == 0)
3350 kif->kf_status |= KF_ATTR_VALID;
3351
3352 /*
3353 * Translate file access flags.
3354 */
3355 for (i = 0; i < NFFLAGS; i++)
3356 if (fflags & fflags_table[i].fflag)
3357 kif->kf_flags |= fflags_table[i].kf_fflag;
3358 if (fd_is_cap)
3359 kif->kf_flags |= KF_FLAG_CAPABILITY;
3360 if (fd_is_cap)
3361 kif->kf_cap_rights = fd_cap_rights;
3362 kif->kf_fd = fd;
3363 kif->kf_type = type;
3364 kif->kf_ref_count = refcnt;
3365 kif->kf_offset = offset;
3366 /* Pack record size down */
3367 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) +
3368 strlen(kif->kf_path) + 1;
3369 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t));
3370 if (efbuf->remainder != -1) {
3371 if (efbuf->remainder < kif->kf_structsize) {
3372 /* Terminate export. */
3373 efbuf->remainder = 0;
3374 if (efbuf->fdp != NULL && !locked)
3375 FILEDESC_SLOCK(efbuf->fdp);
3376 return (0);
3377 }
3378 efbuf->remainder -= kif->kf_structsize;
3379 }
3380 if (locked)
3381 FILEDESC_SUNLOCK(efbuf->fdp);
3382 error = sbuf_bcat(efbuf->sb, kif, kif->kf_structsize);
3383 if (efbuf->fdp != NULL)
3384 FILEDESC_SLOCK(efbuf->fdp);
3385 return (error);
3386 }
3387
3388 /*
3389 * Store a process file descriptor information to sbuf.
3390 *
3391 * Takes a locked proc as argument, and returns with the proc unlocked.
3392 */
3393 int
3394 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen)
3395 {
3396 struct file *fp;
3397 struct filedesc *fdp;
3398 struct export_fd_buf *efbuf;
3399 struct vnode *cttyvp, *textvp, *tracevp;
3400 int64_t offset;
3401 void *data;
3402 int error, i;
3403 int fd_is_cap, type, refcnt, fflags;
3404 cap_rights_t fd_cap_rights;
3405
3406 PROC_LOCK_ASSERT(p, MA_OWNED);
3407
3408 /* ktrace vnode */
3409 tracevp = p->p_tracevp;
3410 if (tracevp != NULL)
3411 vref(tracevp);
3412 /* text vnode */
3413 textvp = p->p_textvp;
3414 if (textvp != NULL)
3415 vref(textvp);
3416 /* Controlling tty. */
3417 cttyvp = NULL;
3418 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) {
3419 cttyvp = p->p_pgrp->pg_session->s_ttyvp;
3420 if (cttyvp != NULL)
3421 vref(cttyvp);
3422 }
3423 fdp = fdhold(p);
3424 PROC_UNLOCK(p);
3425 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK);
3426 efbuf->fdp = NULL;
3427 efbuf->sb = sb;
3428 efbuf->remainder = maxlen;
3429 if (tracevp != NULL)
3430 export_fd_to_sb(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE,
3431 FREAD | FWRITE, -1, -1, 0, 0, efbuf);
3432 if (textvp != NULL)
3433 export_fd_to_sb(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT,
3434 FREAD, -1, -1, 0, 0, efbuf);
3435 if (cttyvp != NULL)
3436 export_fd_to_sb(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY,
3437 FREAD | FWRITE, -1, -1, 0, 0, efbuf);
3438 error = 0;
3439 if (fdp == NULL)
3440 goto fail;
3441 efbuf->fdp = fdp;
3442 FILEDESC_SLOCK(fdp);
3443 /* working directory */
3444 if (fdp->fd_cdir != NULL) {
3445 vref(fdp->fd_cdir);
3446 data = fdp->fd_cdir;
3447 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD,
3448 FREAD, -1, -1, 0, 0, efbuf);
3449 }
3450 /* root directory */
3451 if (fdp->fd_rdir != NULL) {
3452 vref(fdp->fd_rdir);
3453 data = fdp->fd_rdir;
3454 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT,
3455 FREAD, -1, -1, 0, 0, efbuf);
3456 }
3457 /* jail directory */
3458 if (fdp->fd_jdir != NULL) {
3459 vref(fdp->fd_jdir);
3460 data = fdp->fd_jdir;
3461 export_fd_to_sb(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL,
3462 FREAD, -1, -1, 0, 0, efbuf);
3463 }
3464 for (i = 0; i < fdp->fd_nfiles; i++) {
3465 if ((fp = fdp->fd_ofiles[i]) == NULL)
3466 continue;
3467 data = NULL;
3468 fd_is_cap = 0;
3469 fd_cap_rights = 0;
3470
3471 #ifdef CAPABILITIES
3472 /*
3473 * When reporting a capability, most fields will be from the
3474 * underlying object, but do mark as a capability and export
3475 * the capability rights mask.
3476 */
3477 if (fp->f_type == DTYPE_CAPABILITY) {
3478 fd_is_cap = 1;
3479 fd_cap_rights = cap_rights(fp);
3480 (void)cap_funwrap(fp, 0, &fp);
3481 }
3482 #else /* !CAPABILITIES */
3483 KASSERT(fp->f_type != DTYPE_CAPABILITY,
3484 ("sysctl_kern_proc_filedesc: saw capability"));
3485 #endif
3486 switch (fp->f_type) {
3487 case DTYPE_VNODE:
3488 type = KF_TYPE_VNODE;
3489 vref(fp->f_vnode);
3490 data = fp->f_vnode;
3491 break;
3492
3493 case DTYPE_SOCKET:
3494 type = KF_TYPE_SOCKET;
3495 data = fp->f_data;
3496 break;
3497
3498 case DTYPE_PIPE:
3499 type = KF_TYPE_PIPE;
3500 data = fp->f_data;
3501 break;
3502
3503 case DTYPE_FIFO:
3504 type = KF_TYPE_FIFO;
3505 vref(fp->f_vnode);
3506 data = fp->f_vnode;
3507 break;
3508
3509 case DTYPE_KQUEUE:
3510 type = KF_TYPE_KQUEUE;
3511 break;
3512
3513 case DTYPE_CRYPTO:
3514 type = KF_TYPE_CRYPTO;
3515 break;
3516
3517 case DTYPE_MQUEUE:
3518 type = KF_TYPE_MQUEUE;
3519 break;
3520
3521 case DTYPE_SHM:
3522 type = KF_TYPE_SHM;
3523 data = fp;
3524 break;
3525
3526 case DTYPE_SEM:
3527 type = KF_TYPE_SEM;
3528 data = fp;
3529 break;
3530
3531 case DTYPE_PTS:
3532 type = KF_TYPE_PTS;
3533 data = fp->f_data;
3534 break;
3535
3536 #ifdef PROCDESC
3537 case DTYPE_PROCDESC:
3538 type = KF_TYPE_PROCDESC;
3539 data = fp->f_data;
3540 break;
3541 #endif
3542
3543 default:
3544 type = KF_TYPE_UNKNOWN;
3545 break;
3546 }
3547 refcnt = fp->f_count;
3548 fflags = fp->f_flag;
3549 offset = foffset_get(fp);
3550
3551 /*
3552 * Create sysctl entry.
3553 * It is OK to drop the filedesc lock here as we will
3554 * re-validate and re-evaluate its properties when
3555 * the loop continues.
3556 */
3557 error = export_fd_to_sb(data, type, i, fflags, refcnt,
3558 offset, fd_is_cap, fd_cap_rights, efbuf);
3559 if (error)
3560 break;
3561 }
3562 FILEDESC_SUNLOCK(fdp);
3563 fddrop(fdp);
3564 fail:
3565 free(efbuf, M_TEMP);
3566 return (error);
3567 }
3568
3569 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5)
3570
3571 /*
3572 * Get per-process file descriptors for use by procstat(1), et al.
3573 */
3574 static int
3575 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS)
3576 {
3577 struct sbuf sb;
3578 struct proc *p;
3579 ssize_t maxlen;
3580 int error, error2, *name;
3581
3582 name = (int *)arg1;
3583
3584 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req);
3585 error = pget((pid_t)name[0], PGET_CANDEBUG, &p);
3586 if (error != 0) {
3587 sbuf_delete(&sb);
3588 return (error);
3589 }
3590 maxlen = req->oldptr != NULL ? req->oldlen : -1;
3591 error = kern_proc_filedesc_out(p, &sb, maxlen);
3592 error2 = sbuf_finish(&sb);
3593 sbuf_delete(&sb);
3594 return (error != 0 ? error : error2);
3595 }
3596
3597 int
3598 vntype_to_kinfo(int vtype)
3599 {
3600 struct {
3601 int vtype;
3602 int kf_vtype;
3603 } vtypes_table[] = {
3604 { VBAD, KF_VTYPE_VBAD },
3605 { VBLK, KF_VTYPE_VBLK },
3606 { VCHR, KF_VTYPE_VCHR },
3607 { VDIR, KF_VTYPE_VDIR },
3608 { VFIFO, KF_VTYPE_VFIFO },
3609 { VLNK, KF_VTYPE_VLNK },
3610 { VNON, KF_VTYPE_VNON },
3611 { VREG, KF_VTYPE_VREG },
3612 { VSOCK, KF_VTYPE_VSOCK }
3613 };
3614 #define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table))
3615 unsigned int i;
3616
3617 /*
3618 * Perform vtype translation.
3619 */
3620 for (i = 0; i < NVTYPES; i++)
3621 if (vtypes_table[i].vtype == vtype)
3622 break;
3623 if (i < NVTYPES)
3624 return (vtypes_table[i].kf_vtype);
3625
3626 return (KF_VTYPE_UNKNOWN);
3627 }
3628
3629 static int
3630 fill_vnode_info(struct vnode *vp, struct kinfo_file *kif)
3631 {
3632 struct vattr va;
3633 char *fullpath, *freepath;
3634 int error, vfslocked;
3635
3636 if (vp == NULL)
3637 return (1);
3638 kif->kf_vnode_type = vntype_to_kinfo(vp->v_type);
3639 freepath = NULL;
3640 fullpath = "-";
3641 error = vn_fullpath(curthread, vp, &fullpath, &freepath);
3642 if (error == 0) {
3643 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
3644 }
3645 if (freepath != NULL)
3646 free(freepath, M_TEMP);
3647
3648 /*
3649 * Retrieve vnode attributes.
3650 */
3651 va.va_fsid = VNOVAL;
3652 va.va_rdev = NODEV;
3653 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
3654 vn_lock(vp, LK_SHARED | LK_RETRY);
3655 error = VOP_GETATTR(vp, &va, curthread->td_ucred);
3656 VOP_UNLOCK(vp, 0);
3657 VFS_UNLOCK_GIANT(vfslocked);
3658 if (error != 0)
3659 return (error);
3660 if (va.va_fsid != VNOVAL)
3661 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid;
3662 else
3663 kif->kf_un.kf_file.kf_file_fsid =
3664 vp->v_mount->mnt_stat.f_fsid.val[0];
3665 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid;
3666 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode);
3667 kif->kf_un.kf_file.kf_file_size = va.va_size;
3668 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev;
3669 return (0);
3670 }
3671
3672 static int
3673 fill_socket_info(struct socket *so, struct kinfo_file *kif)
3674 {
3675 struct sockaddr *sa;
3676 struct inpcb *inpcb;
3677 struct unpcb *unpcb;
3678 int error;
3679
3680 if (so == NULL)
3681 return (1);
3682 kif->kf_sock_domain = so->so_proto->pr_domain->dom_family;
3683 kif->kf_sock_type = so->so_type;
3684 kif->kf_sock_protocol = so->so_proto->pr_protocol;
3685 kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb;
3686 switch(kif->kf_sock_domain) {
3687 case AF_INET:
3688 case AF_INET6:
3689 if (kif->kf_sock_protocol == IPPROTO_TCP) {
3690 if (so->so_pcb != NULL) {
3691 inpcb = (struct inpcb *)(so->so_pcb);
3692 kif->kf_un.kf_sock.kf_sock_inpcb =
3693 (uintptr_t)inpcb->inp_ppcb;
3694 }
3695 }
3696 break;
3697 case AF_UNIX:
3698 if (so->so_pcb != NULL) {
3699 unpcb = (struct unpcb *)(so->so_pcb);
3700 if (unpcb->unp_conn) {
3701 kif->kf_un.kf_sock.kf_sock_unpconn =
3702 (uintptr_t)unpcb->unp_conn;
3703 kif->kf_un.kf_sock.kf_sock_rcv_sb_state =
3704 so->so_rcv.sb_state;
3705 kif->kf_un.kf_sock.kf_sock_snd_sb_state =
3706 so->so_snd.sb_state;
3707 }
3708 }
3709 break;
3710 }
3711 error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
3712 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) {
3713 bcopy(sa, &kif->kf_sa_local, sa->sa_len);
3714 free(sa, M_SONAME);
3715 }
3716 error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa);
3717 if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) {
3718 bcopy(sa, &kif->kf_sa_peer, sa->sa_len);
3719 free(sa, M_SONAME);
3720 }
3721 strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name,
3722 sizeof(kif->kf_path));
3723 return (0);
3724 }
3725
3726 static int
3727 fill_pts_info(struct tty *tp, struct kinfo_file *kif)
3728 {
3729
3730 if (tp == NULL)
3731 return (1);
3732 kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp);
3733 strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path));
3734 return (0);
3735 }
3736
3737 static int
3738 fill_pipe_info(struct pipe *pi, struct kinfo_file *kif)
3739 {
3740
3741 if (pi == NULL)
3742 return (1);
3743 kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi;
3744 kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer;
3745 kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt;
3746 return (0);
3747 }
3748
3749 static int
3750 fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif)
3751 {
3752
3753 if (pdp == NULL)
3754 return (1);
3755 kif->kf_un.kf_proc.kf_pid = pdp->pd_pid;
3756 return (0);
3757 }
3758
3759 static int
3760 fill_sem_info(struct file *fp, struct kinfo_file *kif)
3761 {
3762 struct thread *td;
3763 struct stat sb;
3764
3765 td = curthread;
3766 if (fp->f_data == NULL)
3767 return (1);
3768 if (fo_stat(fp, &sb, td->td_ucred, td) != 0)
3769 return (1);
3770 if (ksem_info == NULL)
3771 return (1);
3772 ksem_info(fp->f_data, kif->kf_path, sizeof(kif->kf_path),
3773 &kif->kf_un.kf_sem.kf_sem_value);
3774 kif->kf_un.kf_sem.kf_sem_mode = sb.st_mode;
3775 return (0);
3776 }
3777
3778 static int
3779 fill_shm_info(struct file *fp, struct kinfo_file *kif)
3780 {
3781 struct thread *td;
3782 struct stat sb;
3783
3784 td = curthread;
3785 if (fp->f_data == NULL)
3786 return (1);
3787 if (fo_stat(fp, &sb, td->td_ucred, td) != 0)
3788 return (1);
3789 shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path));
3790 kif->kf_un.kf_file.kf_file_mode = sb.st_mode;
3791 kif->kf_un.kf_file.kf_file_size = sb.st_size;
3792 return (0);
3793 }
3794
3795 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD,
3796 sysctl_kern_proc_filedesc, "Process filedesc entries");
3797
3798 #ifdef DDB
3799 /*
3800 * For the purposes of debugging, generate a human-readable string for the
3801 * file type.
3802 */
3803 static const char *
3804 file_type_to_name(short type)
3805 {
3806
3807 switch (type) {
3808 case 0:
3809 return ("zero");
3810 case DTYPE_VNODE:
3811 return ("vnod");
3812 case DTYPE_SOCKET:
3813 return ("sock");
3814 case DTYPE_PIPE:
3815 return ("pipe");
3816 case DTYPE_FIFO:
3817 return ("fifo");
3818 case DTYPE_KQUEUE:
3819 return ("kque");
3820 case DTYPE_CRYPTO:
3821 return ("crpt");
3822 case DTYPE_MQUEUE:
3823 return ("mque");
3824 case DTYPE_SHM:
3825 return ("shm");
3826 case DTYPE_SEM:
3827 return ("ksem");
3828 default:
3829 return ("unkn");
3830 }
3831 }
3832
3833 /*
3834 * For the purposes of debugging, identify a process (if any, perhaps one of
3835 * many) that references the passed file in its file descriptor array. Return
3836 * NULL if none.
3837 */
3838 static struct proc *
3839 file_to_first_proc(struct file *fp)
3840 {
3841 struct filedesc *fdp;
3842 struct proc *p;
3843 int n;
3844
3845 FOREACH_PROC_IN_SYSTEM(p) {
3846 if (p->p_state == PRS_NEW)
3847 continue;
3848 fdp = p->p_fd;
3849 if (fdp == NULL)
3850 continue;
3851 for (n = 0; n < fdp->fd_nfiles; n++) {
3852 if (fp == fdp->fd_ofiles[n])
3853 return (p);
3854 }
3855 }
3856 return (NULL);
3857 }
3858
3859 static void
3860 db_print_file(struct file *fp, int header)
3861 {
3862 struct proc *p;
3863
3864 if (header)
3865 db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n",
3866 "File", "Type", "Data", "Flag", "GCFl", "Count",
3867 "MCount", "Vnode", "FPID", "FCmd");
3868 p = file_to_first_proc(fp);
3869 db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp,
3870 file_type_to_name(fp->f_type), fp->f_data, fp->f_flag,
3871 0, fp->f_count, 0, fp->f_vnode,
3872 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-");
3873 }
3874
3875 DB_SHOW_COMMAND(file, db_show_file)
3876 {
3877 struct file *fp;
3878
3879 if (!have_addr) {
3880 db_printf("usage: show file <addr>\n");
3881 return;
3882 }
3883 fp = (struct file *)addr;
3884 db_print_file(fp, 1);
3885 }
3886
3887 DB_SHOW_COMMAND(files, db_show_files)
3888 {
3889 struct filedesc *fdp;
3890 struct file *fp;
3891 struct proc *p;
3892 int header;
3893 int n;
3894
3895 header = 1;
3896 FOREACH_PROC_IN_SYSTEM(p) {
3897 if (p->p_state == PRS_NEW)
3898 continue;
3899 if ((fdp = p->p_fd) == NULL)
3900 continue;
3901 for (n = 0; n < fdp->fd_nfiles; ++n) {
3902 if ((fp = fdp->fd_ofiles[n]) == NULL)
3903 continue;
3904 db_print_file(fp, header);
3905 header = 0;
3906 }
3907 }
3908 }
3909 #endif
3910
3911 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW,
3912 &maxfilesperproc, 0, "Maximum files allowed open per process");
3913
3914 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW,
3915 &maxfiles, 0, "Maximum number of files");
3916
3917 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD,
3918 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files");
3919
3920 /* ARGSUSED*/
3921 static void
3922 filelistinit(void *dummy)
3923 {
3924
3925 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL,
3926 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
3927 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF);
3928 mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF);
3929 }
3930 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL);
3931
3932 /*-------------------------------------------------------------------*/
3933
3934 static int
3935 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred,
3936 int flags, struct thread *td)
3937 {
3938
3939 return (EBADF);
3940 }
3941
3942 static int
3943 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
3944 struct thread *td)
3945 {
3946
3947 return (EINVAL);
3948 }
3949
3950 static int
3951 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
3952 struct thread *td)
3953 {
3954
3955 return (EBADF);
3956 }
3957
3958 static int
3959 badfo_poll(struct file *fp, int events, struct ucred *active_cred,
3960 struct thread *td)
3961 {
3962
3963 return (0);
3964 }
3965
3966 static int
3967 badfo_kqfilter(struct file *fp, struct knote *kn)
3968 {
3969
3970 return (EBADF);
3971 }
3972
3973 static int
3974 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
3975 struct thread *td)
3976 {
3977
3978 return (EBADF);
3979 }
3980
3981 static int
3982 badfo_close(struct file *fp, struct thread *td)
3983 {
3984
3985 return (EBADF);
3986 }
3987
3988 static int
3989 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
3990 struct thread *td)
3991 {
3992
3993 return (EBADF);
3994 }
3995
3996 static int
3997 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
3998 struct thread *td)
3999 {
4000
4001 return (EBADF);
4002 }
4003
4004 struct fileops badfileops = {
4005 .fo_read = badfo_readwrite,
4006 .fo_write = badfo_readwrite,
4007 .fo_truncate = badfo_truncate,
4008 .fo_ioctl = badfo_ioctl,
4009 .fo_poll = badfo_poll,
4010 .fo_kqfilter = badfo_kqfilter,
4011 .fo_stat = badfo_stat,
4012 .fo_close = badfo_close,
4013 .fo_chmod = badfo_chmod,
4014 .fo_chown = badfo_chown,
4015 };
4016
4017 int
4018 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
4019 struct thread *td)
4020 {
4021
4022 return (EINVAL);
4023 }
4024
4025 int
4026 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
4027 struct thread *td)
4028 {
4029
4030 return (EINVAL);
4031 }
4032
4033 /*-------------------------------------------------------------------*/
4034
4035 /*
4036 * File Descriptor pseudo-device driver (/dev/fd/).
4037 *
4038 * Opening minor device N dup()s the file (if any) connected to file
4039 * descriptor N belonging to the calling process. Note that this driver
4040 * consists of only the ``open()'' routine, because all subsequent
4041 * references to this file will be direct to the other driver.
4042 *
4043 * XXX: we could give this one a cloning event handler if necessary.
4044 */
4045
4046 /* ARGSUSED */
4047 static int
4048 fdopen(struct cdev *dev, int mode, int type, struct thread *td)
4049 {
4050
4051 /*
4052 * XXX Kludge: set curthread->td_dupfd to contain the value of the
4053 * the file descriptor being sought for duplication. The error
4054 * return ensures that the vnode for this device will be released
4055 * by vn_open. Open will detect this special error and take the
4056 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN
4057 * will simply report the error.
4058 */
4059 td->td_dupfd = dev2unit(dev);
4060 return (ENODEV);
4061 }
4062
4063 static struct cdevsw fildesc_cdevsw = {
4064 .d_version = D_VERSION,
4065 .d_open = fdopen,
4066 .d_name = "FD",
4067 };
4068
4069 static void
4070 fildesc_drvinit(void *unused)
4071 {
4072 struct cdev *dev;
4073
4074 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL,
4075 UID_ROOT, GID_WHEEL, 0666, "fd/0");
4076 make_dev_alias(dev, "stdin");
4077 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL,
4078 UID_ROOT, GID_WHEEL, 0666, "fd/1");
4079 make_dev_alias(dev, "stdout");
4080 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL,
4081 UID_ROOT, GID_WHEEL, 0666, "fd/2");
4082 make_dev_alias(dev, "stderr");
4083 }
4084
4085 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL);
Cache object: c65ade3f52d3e0ef259da4bd128077f8
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