2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
42 #include "opt_capsicum.h"
44 #include "opt_ktrace.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
49 #include <sys/capsicum.h>
51 #include <sys/fcntl.h>
53 #include <sys/filedesc.h>
54 #include <sys/filio.h>
56 #include <sys/kernel.h>
57 #include <sys/limits.h>
59 #include <sys/malloc.h>
60 #include <sys/mount.h>
61 #include <sys/mutex.h>
62 #include <sys/namei.h>
63 #include <sys/selinfo.h>
66 #include <sys/protosw.h>
67 #include <sys/racct.h>
68 #include <sys/resourcevar.h>
70 #include <sys/signalvar.h>
74 #include <sys/syscallsubr.h>
75 #include <sys/sysctl.h>
76 #include <sys/sysproto.h>
77 #include <sys/unistd.h>
79 #include <sys/vnode.h>
81 #include <sys/ktrace.h>
86 #include <security/audit/audit.h>
93 static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table");
94 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader",
95 "file desc to leader structures");
96 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures");
97 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities");
99 MALLOC_DECLARE(M_FADVISE);
101 static __read_mostly uma_zone_t file_zone;
102 static __read_mostly uma_zone_t filedesc0_zone;
104 static int closefp(struct filedesc *fdp, int fd, struct file *fp,
105 struct thread *td, int holdleaders);
106 static int fd_first_free(struct filedesc *fdp, int low, int size);
107 static int fd_last_used(struct filedesc *fdp, int size);
108 static void fdgrowtable(struct filedesc *fdp, int nfd);
109 static void fdgrowtable_exp(struct filedesc *fdp, int nfd);
110 static void fdunused(struct filedesc *fdp, int fd);
111 static void fdused(struct filedesc *fdp, int fd);
112 static int getmaxfd(struct thread *td);
113 static u_long *filecaps_copy_prep(const struct filecaps *src);
114 static void filecaps_copy_finish(const struct filecaps *src,
115 struct filecaps *dst, u_long *ioctls);
116 static u_long *filecaps_free_prep(struct filecaps *fcaps);
117 static void filecaps_free_finish(u_long *ioctls);
122 * - An array of open file descriptors (fd_ofiles)
123 * - An array of file flags (fd_ofileflags)
124 * - A bitmap recording which descriptors are in use (fd_map)
126 * A process starts out with NDFILE descriptors. The value of NDFILE has
127 * been selected based the historical limit of 20 open files, and an
128 * assumption that the majority of processes, especially short-lived
129 * processes like shells, will never need more.
131 * If this initial allocation is exhausted, a larger descriptor table and
132 * map are allocated dynamically, and the pointers in the process's struct
133 * filedesc are updated to point to those. This is repeated every time
134 * the process runs out of file descriptors (provided it hasn't hit its
137 * Since threads may hold references to individual descriptor table
138 * entries, the tables are never freed. Instead, they are placed on a
139 * linked list and freed only when the struct filedesc is released.
142 #define NDSLOTSIZE sizeof(NDSLOTTYPE)
143 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT)
144 #define NDSLOT(x) ((x) / NDENTRIES)
145 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES))
146 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES)
149 * SLIST entry used to keep track of ofiles which must be reclaimed when
153 struct fdescenttbl *ft_table;
154 SLIST_ENTRY(freetable) ft_next;
158 * Initial allocation: a filedesc structure + the head of SLIST used to
159 * keep track of old ofiles + enough space for NDFILE descriptors.
162 struct fdescenttbl0 {
164 struct filedescent fdt_ofiles[NDFILE];
168 struct filedesc fd_fd;
169 SLIST_HEAD(, freetable) fd_free;
170 struct fdescenttbl0 fd_dfiles;
171 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)];
175 * Descriptor management.
177 volatile int __exclusive_cache_line openfiles; /* actual number of open files */
178 struct mtx sigio_lock; /* mtx to protect pointers to sigio */
179 void __read_mostly (*mq_fdclose)(struct thread *td, int fd, struct file *fp);
182 * If low >= size, just return low. Otherwise find the first zero bit in the
183 * given bitmap, starting at low and not exceeding size - 1. Return size if
187 fd_first_free(struct filedesc *fdp, int low, int size)
189 NDSLOTTYPE *map = fdp->fd_map;
197 if (low % NDENTRIES) {
198 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES)));
199 if ((mask &= ~map[off]) != 0UL)
200 return (off * NDENTRIES + ffsl(mask) - 1);
203 for (maxoff = NDSLOTS(size); off < maxoff; ++off)
204 if (map[off] != ~0UL)
205 return (off * NDENTRIES + ffsl(~map[off]) - 1);
210 * Find the highest non-zero bit in the given bitmap, starting at 0 and
211 * not exceeding size - 1. Return -1 if not found.
214 fd_last_used(struct filedesc *fdp, int size)
216 NDSLOTTYPE *map = fdp->fd_map;
221 if (size % NDENTRIES) {
222 mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES));
223 if ((mask &= map[off]) != 0)
224 return (off * NDENTRIES + flsl(mask) - 1);
227 for (minoff = NDSLOT(0); off >= minoff; --off)
229 return (off * NDENTRIES + flsl(map[off]) - 1);
234 fdisused(struct filedesc *fdp, int fd)
237 KASSERT(fd >= 0 && fd < fdp->fd_nfiles,
238 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles));
240 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0);
244 * Mark a file descriptor as used.
247 fdused_init(struct filedesc *fdp, int fd)
250 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd));
252 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd);
256 fdused(struct filedesc *fdp, int fd)
259 FILEDESC_XLOCK_ASSERT(fdp);
261 fdused_init(fdp, fd);
262 if (fd > fdp->fd_lastfile)
263 fdp->fd_lastfile = fd;
264 if (fd == fdp->fd_freefile)
269 * Mark a file descriptor as unused.
272 fdunused(struct filedesc *fdp, int fd)
275 FILEDESC_XLOCK_ASSERT(fdp);
277 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd));
278 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL,
279 ("fd=%d is still in use", fd));
281 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd);
282 if (fd < fdp->fd_freefile)
283 fdp->fd_freefile = fd;
284 if (fd == fdp->fd_lastfile)
285 fdp->fd_lastfile = fd_last_used(fdp, fd);
289 * Free a file descriptor.
291 * Avoid some work if fdp is about to be destroyed.
294 fdefree_last(struct filedescent *fde)
297 filecaps_free(&fde->fde_caps);
301 fdfree(struct filedesc *fdp, int fd)
303 struct filedescent *fde;
305 fde = &fdp->fd_ofiles[fd];
307 seqc_write_begin(&fde->fde_seqc);
309 fde->fde_file = NULL;
311 seqc_write_end(&fde->fde_seqc);
318 pwd_ensure_dirs(void)
320 struct filedesc *fdp;
324 if (fdp->fd_cdir == NULL) {
325 fdp->fd_cdir = rootvnode;
328 if (fdp->fd_rdir == NULL) {
329 fdp->fd_rdir = rootvnode;
332 FILEDESC_XUNLOCK(fdp);
336 * System calls on descriptors.
338 #ifndef _SYS_SYSPROTO_H_
339 struct getdtablesize_args {
345 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap)
351 td->td_retval[0] = getmaxfd(td);
353 PROC_LOCK(td->td_proc);
354 lim = racct_get_limit(td->td_proc, RACCT_NOFILE);
355 PROC_UNLOCK(td->td_proc);
356 if (lim < td->td_retval[0])
357 td->td_retval[0] = lim;
363 * Duplicate a file descriptor to a particular value.
365 * Note: keep in mind that a potential race condition exists when closing
366 * descriptors from a shared descriptor table (via rfork).
368 #ifndef _SYS_SYSPROTO_H_
376 sys_dup2(struct thread *td, struct dup2_args *uap)
379 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to));
383 * Duplicate a file descriptor.
385 #ifndef _SYS_SYSPROTO_H_
392 sys_dup(struct thread *td, struct dup_args *uap)
395 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0));
399 * The file control system call.
401 #ifndef _SYS_SYSPROTO_H_
410 sys_fcntl(struct thread *td, struct fcntl_args *uap)
413 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg));
417 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg)
431 * Convert old flock structure to new.
433 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl));
434 fl.l_start = ofl.l_start;
435 fl.l_len = ofl.l_len;
436 fl.l_pid = ofl.l_pid;
437 fl.l_type = ofl.l_type;
438 fl.l_whence = ofl.l_whence;
452 arg1 = (intptr_t)&fl;
458 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl));
459 arg1 = (intptr_t)&fl;
467 error = kern_fcntl(td, fd, newcmd, arg1);
470 if (cmd == F_OGETLK) {
471 ofl.l_start = fl.l_start;
472 ofl.l_len = fl.l_len;
473 ofl.l_pid = fl.l_pid;
474 ofl.l_type = fl.l_type;
475 ofl.l_whence = fl.l_whence;
476 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl));
477 } else if (cmd == F_GETLK) {
478 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl));
484 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg)
486 struct filedesc *fdp;
488 struct file *fp, *fp2;
489 struct filedescent *fde;
506 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp);
509 case F_DUPFD_CLOEXEC:
511 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp);
516 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp);
519 case F_DUP2FD_CLOEXEC:
521 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp);
527 fde = fdeget_locked(fdp, fd);
530 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0;
533 FILEDESC_SUNLOCK(fdp);
539 fde = fdeget_locked(fdp, fd);
541 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) |
542 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0);
545 FILEDESC_XUNLOCK(fdp);
549 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETFL, &fp);
552 td->td_retval[0] = OFLAGS(fp->f_flag);
557 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETFL, &fp);
561 tmp = flg = fp->f_flag;
563 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS;
564 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0);
565 tmp = fp->f_flag & FNONBLOCK;
566 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
571 tmp = fp->f_flag & FASYNC;
572 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td);
577 atomic_clear_int(&fp->f_flag, FNONBLOCK);
579 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
584 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETOWN, &fp);
587 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td);
589 td->td_retval[0] = tmp;
594 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETOWN, &fp);
598 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td);
603 error = priv_check(td, PRIV_NFS_LOCKD);
611 /* FALLTHROUGH F_SETLK */
615 flp = (struct flock *)arg;
616 if ((flg & F_REMOTE) != 0 && flp->l_sysid == 0) {
621 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp, NULL);
624 if (fp->f_type != DTYPE_VNODE) {
630 if (flp->l_whence == SEEK_CUR) {
631 foffset = foffset_get(fp);
634 foffset > OFF_MAX - flp->l_start)) {
639 flp->l_start += foffset;
643 switch (flp->l_type) {
645 if ((fp->f_flag & FREAD) == 0) {
649 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) {
650 PROC_LOCK(p->p_leader);
651 p->p_leader->p_flag |= P_ADVLOCK;
652 PROC_UNLOCK(p->p_leader);
654 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
658 if ((fp->f_flag & FWRITE) == 0) {
662 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) {
663 PROC_LOCK(p->p_leader);
664 p->p_leader->p_flag |= P_ADVLOCK;
665 PROC_UNLOCK(p->p_leader);
667 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
671 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK,
675 if (flg != F_REMOTE) {
679 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
680 F_UNLCKSYS, flp, flg);
686 if (error != 0 || flp->l_type == F_UNLCK ||
687 flp->l_type == F_UNLCKSYS) {
693 * Check for a race with close.
695 * The vnode is now advisory locked (or unlocked, but this case
696 * is not really important) as the caller requested.
697 * We had to drop the filedesc lock, so we need to recheck if
698 * the descriptor is still valid, because if it was closed
699 * in the meantime we need to remove advisory lock from the
700 * vnode - close on any descriptor leading to an advisory
701 * locked vnode, removes that lock.
702 * We will return 0 on purpose in that case, as the result of
703 * successful advisory lock might have been externally visible
704 * already. This is fine - effectively we pretend to the caller
705 * that the closing thread was a bit slower and that the
706 * advisory lock succeeded before the close.
708 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp2, NULL);
714 flp->l_whence = SEEK_SET;
717 flp->l_type = F_UNLCK;
718 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
719 F_UNLCK, flp, F_POSIX);
726 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp, NULL);
729 if (fp->f_type != DTYPE_VNODE) {
734 flp = (struct flock *)arg;
735 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK &&
736 flp->l_type != F_UNLCK) {
741 if (flp->l_whence == SEEK_CUR) {
742 foffset = foffset_get(fp);
743 if ((flp->l_start > 0 &&
744 foffset > OFF_MAX - flp->l_start) ||
746 foffset < OFF_MIN - flp->l_start)) {
751 flp->l_start += foffset;
754 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp,
760 arg = arg ? 128 * 1024: 0;
763 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp, NULL);
766 if (fp->f_type != DTYPE_VNODE) {
773 * Exclusive lock synchronizes against f_seqcount reads and
774 * writes in sequential_heuristic().
776 error = vn_lock(vp, LK_EXCLUSIVE);
782 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize;
783 arg = MIN(arg, INT_MAX - bsize + 1);
784 fp->f_seqcount = MIN(IO_SEQMAX,
785 (arg + bsize - 1) / bsize);
786 atomic_set_int(&fp->f_flag, FRDAHEAD);
788 atomic_clear_int(&fp->f_flag, FRDAHEAD);
802 getmaxfd(struct thread *td)
805 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc));
809 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD).
812 kern_dup(struct thread *td, u_int mode, int flags, int old, int new)
814 struct filedesc *fdp;
815 struct filedescent *oldfde, *newfde;
818 u_long *oioctls, *nioctls;
825 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0);
826 MPASS(mode < FDDUP_LASTMODE);
829 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */
832 * Verify we have a valid descriptor to dup from and possibly to
833 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should
834 * return EINVAL when the new descriptor is out of bounds.
839 return (mode == FDDUP_FCNTL ? EINVAL : EBADF);
840 maxfd = getmaxfd(td);
842 return (mode == FDDUP_FCNTL ? EINVAL : EBADF);
846 if (fget_locked(fdp, old) == NULL)
848 if ((mode == FDDUP_FIXED || mode == FDDUP_MUSTREPLACE) && old == new) {
849 td->td_retval[0] = new;
850 if (flags & FDDUP_FLAG_CLOEXEC)
851 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE;
856 oldfde = &fdp->fd_ofiles[old];
857 if (!fhold(oldfde->fde_file))
861 * If the caller specified a file descriptor, make sure the file
862 * table is large enough to hold it, and grab it. Otherwise, just
863 * allocate a new descriptor the usual way.
868 if ((error = fdalloc(td, new, &new)) != 0) {
869 fdrop(oldfde->fde_file, td);
873 case FDDUP_MUSTREPLACE:
874 /* Target file descriptor must exist. */
875 if (fget_locked(fdp, new) == NULL) {
876 fdrop(oldfde->fde_file, td);
881 if (new >= fdp->fd_nfiles) {
883 * The resource limits are here instead of e.g.
884 * fdalloc(), because the file descriptor table may be
885 * shared between processes, so we can't really use
886 * racct_add()/racct_sub(). Instead of counting the
887 * number of actually allocated descriptors, just put
888 * the limit on the size of the file descriptor table.
891 if (RACCT_ENABLED()) {
892 error = racct_set_unlocked(p, RACCT_NOFILE, new + 1);
895 fdrop(oldfde->fde_file, td);
900 fdgrowtable_exp(fdp, new + 1);
902 if (!fdisused(fdp, new))
906 KASSERT(0, ("%s unsupported mode %d", __func__, mode));
909 KASSERT(old != new, ("new fd is same as old"));
911 newfde = &fdp->fd_ofiles[new];
912 delfp = newfde->fde_file;
914 oioctls = filecaps_free_prep(&newfde->fde_caps);
915 nioctls = filecaps_copy_prep(&oldfde->fde_caps);
918 * Duplicate the source descriptor.
921 seqc_write_begin(&newfde->fde_seqc);
923 memcpy(newfde, oldfde, fde_change_size);
924 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps,
926 if ((flags & FDDUP_FLAG_CLOEXEC) != 0)
927 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE;
929 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE;
931 seqc_write_end(&newfde->fde_seqc);
933 td->td_retval[0] = new;
938 (void) closefp(fdp, new, delfp, td, 1);
939 FILEDESC_UNLOCK_ASSERT(fdp);
942 FILEDESC_XUNLOCK(fdp);
945 filecaps_free_finish(oioctls);
950 * If sigio is on the list associated with a process or process group,
951 * disable signalling from the device, remove sigio from the list and
955 funsetown(struct sigio **sigiop)
967 *(sigio->sio_myref) = NULL;
968 if ((sigio)->sio_pgid < 0) {
969 struct pgrp *pg = (sigio)->sio_pgrp;
971 SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio,
975 struct proc *p = (sigio)->sio_proc;
977 SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio,
982 crfree(sigio->sio_ucred);
983 free(sigio, M_SIGIO);
987 * Free a list of sigio structures.
988 * We only need to lock the SIGIO_LOCK because we have made ourselves
989 * inaccessible to callers of fsetown and therefore do not need to lock
990 * the proc or pgrp struct for the list manipulation.
993 funsetownlst(struct sigiolst *sigiolst)
999 sigio = SLIST_FIRST(sigiolst);
1006 * Every entry of the list should belong
1007 * to a single proc or pgrp.
1009 if (sigio->sio_pgid < 0) {
1010 pg = sigio->sio_pgrp;
1011 PGRP_LOCK_ASSERT(pg, MA_NOTOWNED);
1012 } else /* if (sigio->sio_pgid > 0) */ {
1013 p = sigio->sio_proc;
1014 PROC_LOCK_ASSERT(p, MA_NOTOWNED);
1018 while ((sigio = SLIST_FIRST(sigiolst)) != NULL) {
1019 *(sigio->sio_myref) = NULL;
1021 KASSERT(sigio->sio_pgid < 0,
1022 ("Proc sigio in pgrp sigio list"));
1023 KASSERT(sigio->sio_pgrp == pg,
1024 ("Bogus pgrp in sigio list"));
1026 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio,
1029 } else /* if (p != NULL) */ {
1030 KASSERT(sigio->sio_pgid > 0,
1031 ("Pgrp sigio in proc sigio list"));
1032 KASSERT(sigio->sio_proc == p,
1033 ("Bogus proc in sigio list"));
1035 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio,
1040 crfree(sigio->sio_ucred);
1041 free(sigio, M_SIGIO);
1048 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg).
1050 * After permission checking, add a sigio structure to the sigio list for
1051 * the process or process group.
1054 fsetown(pid_t pgid, struct sigio **sigiop)
1058 struct sigio *sigio;
1068 /* Allocate and fill in the new sigio out of locks. */
1069 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK);
1070 sigio->sio_pgid = pgid;
1071 sigio->sio_ucred = crhold(curthread->td_ucred);
1072 sigio->sio_myref = sigiop;
1074 sx_slock(&proctree_lock);
1083 * Policy - Don't allow a process to FSETOWN a process
1084 * in another session.
1086 * Remove this test to allow maximum flexibility or
1087 * restrict FSETOWN to the current process or process
1088 * group for maximum safety.
1091 if (proc->p_session != curthread->td_proc->p_session) {
1097 } else /* if (pgid < 0) */ {
1098 pgrp = pgfind(-pgid);
1106 * Policy - Don't allow a process to FSETOWN a process
1107 * in another session.
1109 * Remove this test to allow maximum flexibility or
1110 * restrict FSETOWN to the current process or process
1111 * group for maximum safety.
1113 if (pgrp->pg_session != curthread->td_proc->p_session) {
1124 * Since funsetownlst() is called without the proctree
1125 * locked, we need to check for P_WEXIT.
1126 * XXX: is ESRCH correct?
1128 if ((proc->p_flag & P_WEXIT) != 0) {
1133 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio);
1134 sigio->sio_proc = proc;
1138 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio);
1139 sigio->sio_pgrp = pgrp;
1142 sx_sunlock(&proctree_lock);
1149 sx_sunlock(&proctree_lock);
1150 crfree(sigio->sio_ucred);
1151 free(sigio, M_SIGIO);
1156 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg).
1159 fgetown(struct sigio **sigiop)
1164 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0;
1170 * Function drops the filedesc lock on return.
1173 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td,
1178 FILEDESC_XLOCK_ASSERT(fdp);
1181 if (td->td_proc->p_fdtol != NULL) {
1183 * Ask fdfree() to sleep to ensure that all relevant
1184 * process leaders can be traversed in closef().
1186 fdp->fd_holdleaderscount++;
1193 * We now hold the fp reference that used to be owned by the
1194 * descriptor array. We have to unlock the FILEDESC *AFTER*
1195 * knote_fdclose to prevent a race of the fd getting opened, a knote
1196 * added, and deleteing a knote for the new fd.
1198 if (__predict_false(!TAILQ_EMPTY(&fdp->fd_kqlist)))
1199 knote_fdclose(td, fd);
1202 * We need to notify mqueue if the object is of type mqueue.
1204 if (__predict_false(fp->f_type == DTYPE_MQUEUE))
1205 mq_fdclose(td, fd, fp);
1206 FILEDESC_XUNLOCK(fdp);
1208 error = closef(fp, td);
1210 FILEDESC_XLOCK(fdp);
1211 fdp->fd_holdleaderscount--;
1212 if (fdp->fd_holdleaderscount == 0 &&
1213 fdp->fd_holdleaderswakeup != 0) {
1214 fdp->fd_holdleaderswakeup = 0;
1215 wakeup(&fdp->fd_holdleaderscount);
1217 FILEDESC_XUNLOCK(fdp);
1223 * Close a file descriptor.
1225 #ifndef _SYS_SYSPROTO_H_
1232 sys_close(struct thread *td, struct close_args *uap)
1235 return (kern_close(td, uap->fd));
1239 kern_close(struct thread *td, int fd)
1241 struct filedesc *fdp;
1244 fdp = td->td_proc->p_fd;
1246 AUDIT_SYSCLOSE(td, fd);
1248 FILEDESC_XLOCK(fdp);
1249 if ((fp = fget_locked(fdp, fd)) == NULL) {
1250 FILEDESC_XUNLOCK(fdp);
1255 /* closefp() drops the FILEDESC lock for us. */
1256 return (closefp(fdp, fd, fp, td, 1));
1260 * Close open file descriptors.
1262 #ifndef _SYS_SYSPROTO_H_
1263 struct closefrom_args {
1269 sys_closefrom(struct thread *td, struct closefrom_args *uap)
1271 struct filedesc *fdp;
1274 fdp = td->td_proc->p_fd;
1275 AUDIT_ARG_FD(uap->lowfd);
1278 * Treat negative starting file descriptor values identical to
1279 * closefrom(0) which closes all files.
1283 FILEDESC_SLOCK(fdp);
1284 for (fd = uap->lowfd; fd <= fdp->fd_lastfile; fd++) {
1285 if (fdp->fd_ofiles[fd].fde_file != NULL) {
1286 FILEDESC_SUNLOCK(fdp);
1287 (void)kern_close(td, fd);
1288 FILEDESC_SLOCK(fdp);
1291 FILEDESC_SUNLOCK(fdp);
1295 #if defined(COMPAT_43)
1297 * Return status information about a file descriptor.
1299 #ifndef _SYS_SYSPROTO_H_
1300 struct ofstat_args {
1307 ofstat(struct thread *td, struct ofstat_args *uap)
1313 error = kern_fstat(td, uap->fd, &ub);
1316 error = copyout(&oub, uap->sb, sizeof(oub));
1320 #endif /* COMPAT_43 */
1322 #if defined(COMPAT_FREEBSD11)
1324 freebsd11_fstat(struct thread *td, struct freebsd11_fstat_args *uap)
1327 struct freebsd11_stat osb;
1330 error = kern_fstat(td, uap->fd, &sb);
1333 error = freebsd11_cvtstat(&sb, &osb);
1335 error = copyout(&osb, uap->sb, sizeof(osb));
1338 #endif /* COMPAT_FREEBSD11 */
1341 * Return status information about a file descriptor.
1343 #ifndef _SYS_SYSPROTO_H_
1351 sys_fstat(struct thread *td, struct fstat_args *uap)
1356 error = kern_fstat(td, uap->fd, &ub);
1358 error = copyout(&ub, uap->sb, sizeof(ub));
1363 kern_fstat(struct thread *td, int fd, struct stat *sbp)
1370 error = fget(td, fd, &cap_fstat_rights, &fp);
1374 AUDIT_ARG_FILE(td->td_proc, fp);
1376 error = fo_stat(fp, sbp, td->td_ucred, td);
1378 #ifdef __STAT_TIME_T_EXT
1380 sbp->st_atim_ext = 0;
1381 sbp->st_mtim_ext = 0;
1382 sbp->st_ctim_ext = 0;
1383 sbp->st_btim_ext = 0;
1387 if (error == 0 && KTRPOINT(td, KTR_STRUCT))
1393 #if defined(COMPAT_FREEBSD11)
1395 * Return status information about a file descriptor.
1397 #ifndef _SYS_SYSPROTO_H_
1398 struct freebsd11_nfstat_args {
1405 freebsd11_nfstat(struct thread *td, struct freebsd11_nfstat_args *uap)
1411 error = kern_fstat(td, uap->fd, &ub);
1413 freebsd11_cvtnstat(&ub, &nub);
1414 error = copyout(&nub, uap->sb, sizeof(nub));
1418 #endif /* COMPAT_FREEBSD11 */
1421 * Return pathconf information about a file descriptor.
1423 #ifndef _SYS_SYSPROTO_H_
1424 struct fpathconf_args {
1431 sys_fpathconf(struct thread *td, struct fpathconf_args *uap)
1436 error = kern_fpathconf(td, uap->fd, uap->name, &value);
1438 td->td_retval[0] = value;
1443 kern_fpathconf(struct thread *td, int fd, int name, long *valuep)
1449 error = fget(td, fd, &cap_fpathconf_rights, &fp);
1453 if (name == _PC_ASYNC_IO) {
1454 *valuep = _POSIX_ASYNCHRONOUS_IO;
1459 vn_lock(vp, LK_SHARED | LK_RETRY);
1460 error = VOP_PATHCONF(vp, name, valuep);
1462 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) {
1463 if (name != _PC_PIPE_BUF) {
1478 * Copy filecaps structure allocating memory for ioctls array if needed.
1480 * The last parameter indicates whether the fdtable is locked. If it is not and
1481 * ioctls are encountered, copying fails and the caller must lock the table.
1483 * Note that if the table was not locked, the caller has to check the relevant
1484 * sequence counter to determine whether the operation was successful.
1487 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked)
1491 if (src->fc_ioctls != NULL && !locked)
1493 memcpy(dst, src, sizeof(*src));
1494 if (src->fc_ioctls == NULL)
1497 KASSERT(src->fc_nioctls > 0,
1498 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1500 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1501 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1502 memcpy(dst->fc_ioctls, src->fc_ioctls, size);
1507 filecaps_copy_prep(const struct filecaps *src)
1512 if (__predict_true(src->fc_ioctls == NULL))
1515 KASSERT(src->fc_nioctls > 0,
1516 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1518 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1519 ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1524 filecaps_copy_finish(const struct filecaps *src, struct filecaps *dst,
1530 if (__predict_true(src->fc_ioctls == NULL)) {
1531 MPASS(ioctls == NULL);
1535 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1536 dst->fc_ioctls = ioctls;
1537 bcopy(src->fc_ioctls, dst->fc_ioctls, size);
1541 * Move filecaps structure to the new place and clear the old place.
1544 filecaps_move(struct filecaps *src, struct filecaps *dst)
1548 bzero(src, sizeof(*src));
1552 * Fill the given filecaps structure with full rights.
1555 filecaps_fill(struct filecaps *fcaps)
1558 CAP_ALL(&fcaps->fc_rights);
1559 fcaps->fc_ioctls = NULL;
1560 fcaps->fc_nioctls = -1;
1561 fcaps->fc_fcntls = CAP_FCNTL_ALL;
1565 * Free memory allocated within filecaps structure.
1568 filecaps_free(struct filecaps *fcaps)
1571 free(fcaps->fc_ioctls, M_FILECAPS);
1572 bzero(fcaps, sizeof(*fcaps));
1576 filecaps_free_prep(struct filecaps *fcaps)
1580 ioctls = fcaps->fc_ioctls;
1581 bzero(fcaps, sizeof(*fcaps));
1586 filecaps_free_finish(u_long *ioctls)
1589 free(ioctls, M_FILECAPS);
1593 * Validate the given filecaps structure.
1596 filecaps_validate(const struct filecaps *fcaps, const char *func)
1599 KASSERT(cap_rights_is_valid(&fcaps->fc_rights),
1600 ("%s: invalid rights", func));
1601 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0,
1602 ("%s: invalid fcntls", func));
1603 KASSERT(fcaps->fc_fcntls == 0 ||
1604 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL),
1605 ("%s: fcntls without CAP_FCNTL", func));
1606 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 :
1607 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0),
1608 ("%s: invalid ioctls", func));
1609 KASSERT(fcaps->fc_nioctls == 0 ||
1610 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL),
1611 ("%s: ioctls without CAP_IOCTL", func));
1615 fdgrowtable_exp(struct filedesc *fdp, int nfd)
1619 FILEDESC_XLOCK_ASSERT(fdp);
1621 nfd1 = fdp->fd_nfiles * 2;
1624 fdgrowtable(fdp, nfd1);
1628 * Grow the file table to accommodate (at least) nfd descriptors.
1631 fdgrowtable(struct filedesc *fdp, int nfd)
1633 struct filedesc0 *fdp0;
1634 struct freetable *ft;
1635 struct fdescenttbl *ntable;
1636 struct fdescenttbl *otable;
1637 int nnfiles, onfiles;
1638 NDSLOTTYPE *nmap, *omap;
1641 * If lastfile is -1 this struct filedesc was just allocated and we are
1642 * growing it to accommodate for the one we are going to copy from. There
1643 * is no need to have a lock on this one as it's not visible to anyone.
1645 if (fdp->fd_lastfile != -1)
1646 FILEDESC_XLOCK_ASSERT(fdp);
1648 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table"));
1650 /* save old values */
1651 onfiles = fdp->fd_nfiles;
1652 otable = fdp->fd_files;
1655 /* compute the size of the new table */
1656 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */
1657 if (nnfiles <= onfiles)
1658 /* the table is already large enough */
1662 * Allocate a new table. We need enough space for the number of
1663 * entries, file entries themselves and the struct freetable we will use
1664 * when we decommission the table and place it on the freelist.
1665 * We place the struct freetable in the middle so we don't have
1666 * to worry about padding.
1668 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) +
1669 nnfiles * sizeof(ntable->fdt_ofiles[0]) +
1670 sizeof(struct freetable),
1671 M_FILEDESC, M_ZERO | M_WAITOK);
1672 /* copy the old data */
1673 ntable->fdt_nfiles = nnfiles;
1674 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles,
1675 onfiles * sizeof(ntable->fdt_ofiles[0]));
1678 * Allocate a new map only if the old is not large enough. It will
1679 * grow at a slower rate than the table as it can map more
1680 * entries than the table can hold.
1682 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) {
1683 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC,
1685 /* copy over the old data and update the pointer */
1686 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap));
1691 * Make sure that ntable is correctly initialized before we replace
1692 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent
1695 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable);
1698 * Do not free the old file table, as some threads may still
1699 * reference entries within it. Instead, place it on a freelist
1700 * which will be processed when the struct filedesc is released.
1702 * Note that if onfiles == NDFILE, we're dealing with the original
1703 * static allocation contained within (struct filedesc0 *)fdp,
1704 * which must not be freed.
1706 if (onfiles > NDFILE) {
1707 ft = (struct freetable *)&otable->fdt_ofiles[onfiles];
1708 fdp0 = (struct filedesc0 *)fdp;
1709 ft->ft_table = otable;
1710 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next);
1713 * The map does not have the same possibility of threads still
1714 * holding references to it. So always free it as long as it
1715 * does not reference the original static allocation.
1717 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE))
1718 free(omap, M_FILEDESC);
1722 * Allocate a file descriptor for the process.
1725 fdalloc(struct thread *td, int minfd, int *result)
1727 struct proc *p = td->td_proc;
1728 struct filedesc *fdp = p->p_fd;
1729 int fd, maxfd, allocfd;
1734 FILEDESC_XLOCK_ASSERT(fdp);
1736 if (fdp->fd_freefile > minfd)
1737 minfd = fdp->fd_freefile;
1739 maxfd = getmaxfd(td);
1742 * Search the bitmap for a free descriptor starting at minfd.
1743 * If none is found, grow the file table.
1745 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles);
1748 if (fd >= fdp->fd_nfiles) {
1749 allocfd = min(fd * 2, maxfd);
1751 if (RACCT_ENABLED()) {
1752 error = racct_set_unlocked(p, RACCT_NOFILE, allocfd);
1758 * fd is already equal to first free descriptor >= minfd, so
1759 * we only need to grow the table and we are done.
1761 fdgrowtable_exp(fdp, allocfd);
1765 * Perform some sanity checks, then mark the file descriptor as
1766 * used and return it to the caller.
1768 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles),
1769 ("invalid descriptor %d", fd));
1770 KASSERT(!fdisused(fdp, fd),
1771 ("fd_first_free() returned non-free descriptor"));
1772 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL,
1773 ("file descriptor isn't free"));
1780 * Allocate n file descriptors for the process.
1783 fdallocn(struct thread *td, int minfd, int *fds, int n)
1785 struct proc *p = td->td_proc;
1786 struct filedesc *fdp = p->p_fd;
1789 FILEDESC_XLOCK_ASSERT(fdp);
1791 for (i = 0; i < n; i++)
1792 if (fdalloc(td, 0, &fds[i]) != 0)
1796 for (i--; i >= 0; i--)
1797 fdunused(fdp, fds[i]);
1805 * Create a new open file structure and allocate a file descriptor for the
1806 * process that refers to it. We add one reference to the file for the
1807 * descriptor table and one reference for resultfp. This is to prevent us
1808 * being preempted and the entry in the descriptor table closed after we
1809 * release the FILEDESC lock.
1812 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags,
1813 struct filecaps *fcaps)
1818 error = falloc_noinstall(td, &fp);
1820 return (error); /* no reference held on error */
1822 error = finstall(td, fp, &fd, flags, fcaps);
1824 fdrop(fp, td); /* one reference (fp only) */
1828 if (resultfp != NULL)
1829 *resultfp = fp; /* copy out result */
1831 fdrop(fp, td); /* release local reference */
1833 if (resultfd != NULL)
1840 * Create a new open file structure without allocating a file descriptor.
1843 falloc_noinstall(struct thread *td, struct file **resultfp)
1846 int maxuserfiles = maxfiles - (maxfiles / 20);
1848 static struct timeval lastfail;
1851 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__));
1853 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1;
1854 if ((openfiles_new >= maxuserfiles &&
1855 priv_check(td, PRIV_MAXFILES) != 0) ||
1856 openfiles_new >= maxfiles) {
1857 atomic_subtract_int(&openfiles, 1);
1858 if (ppsratecheck(&lastfail, &curfail, 1)) {
1859 printf("kern.maxfiles limit exceeded by uid %i, (%s) "
1860 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm);
1864 fp = uma_zalloc(file_zone, M_WAITOK);
1865 bzero(fp, sizeof(*fp));
1866 refcount_init(&fp->f_count, 1);
1867 fp->f_cred = crhold(td->td_ucred);
1868 fp->f_ops = &badfileops;
1874 * Install a file in a file descriptor table.
1877 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags,
1878 struct filecaps *fcaps)
1880 struct filedescent *fde;
1884 filecaps_validate(fcaps, __func__);
1885 FILEDESC_XLOCK_ASSERT(fdp);
1887 fde = &fdp->fd_ofiles[fd];
1889 seqc_write_begin(&fde->fde_seqc);
1892 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0;
1894 filecaps_move(fcaps, &fde->fde_caps);
1896 filecaps_fill(&fde->fde_caps);
1898 seqc_write_end(&fde->fde_seqc);
1903 finstall(struct thread *td, struct file *fp, int *fd, int flags,
1904 struct filecaps *fcaps)
1906 struct filedesc *fdp = td->td_proc->p_fd;
1913 FILEDESC_XLOCK(fdp);
1914 if ((error = fdalloc(td, 0, fd))) {
1915 FILEDESC_XUNLOCK(fdp);
1919 _finstall(fdp, fp, *fd, flags, fcaps);
1920 FILEDESC_XUNLOCK(fdp);
1925 * Build a new filedesc structure from another.
1926 * Copy the current, root, and jail root vnode references.
1928 * If fdp is not NULL, return with it shared locked.
1931 fdinit(struct filedesc *fdp, bool prepfiles)
1933 struct filedesc0 *newfdp0;
1934 struct filedesc *newfdp;
1936 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO);
1937 newfdp = &newfdp0->fd_fd;
1939 /* Create the file descriptor table. */
1940 FILEDESC_LOCK_INIT(newfdp);
1941 refcount_init(&newfdp->fd_refcnt, 1);
1942 refcount_init(&newfdp->fd_holdcnt, 1);
1943 newfdp->fd_cmask = CMASK;
1944 newfdp->fd_map = newfdp0->fd_dmap;
1945 newfdp->fd_lastfile = -1;
1946 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles;
1947 newfdp->fd_files->fdt_nfiles = NDFILE;
1952 if (prepfiles && fdp->fd_lastfile >= newfdp->fd_nfiles)
1953 fdgrowtable(newfdp, fdp->fd_lastfile + 1);
1955 FILEDESC_SLOCK(fdp);
1956 newfdp->fd_cdir = fdp->fd_cdir;
1957 if (newfdp->fd_cdir)
1958 vrefact(newfdp->fd_cdir);
1959 newfdp->fd_rdir = fdp->fd_rdir;
1960 if (newfdp->fd_rdir)
1961 vrefact(newfdp->fd_rdir);
1962 newfdp->fd_jdir = fdp->fd_jdir;
1963 if (newfdp->fd_jdir)
1964 vrefact(newfdp->fd_jdir);
1967 FILEDESC_SUNLOCK(fdp);
1969 while (fdp->fd_lastfile >= newfdp->fd_nfiles) {
1970 FILEDESC_SUNLOCK(fdp);
1971 fdgrowtable(newfdp, fdp->fd_lastfile + 1);
1972 FILEDESC_SLOCK(fdp);
1979 static struct filedesc *
1980 fdhold(struct proc *p)
1982 struct filedesc *fdp;
1984 PROC_LOCK_ASSERT(p, MA_OWNED);
1987 refcount_acquire(&fdp->fd_holdcnt);
1992 fddrop(struct filedesc *fdp)
1995 if (fdp->fd_holdcnt > 1) {
1996 if (refcount_release(&fdp->fd_holdcnt) == 0)
2000 FILEDESC_LOCK_DESTROY(fdp);
2001 uma_zfree(filedesc0_zone, fdp);
2005 * Share a filedesc structure.
2008 fdshare(struct filedesc *fdp)
2011 refcount_acquire(&fdp->fd_refcnt);
2016 * Unshare a filedesc structure, if necessary by making a copy
2019 fdunshare(struct thread *td)
2021 struct filedesc *tmp;
2022 struct proc *p = td->td_proc;
2024 if (p->p_fd->fd_refcnt == 1)
2027 tmp = fdcopy(p->p_fd);
2033 fdinstall_remapped(struct thread *td, struct filedesc *fdp)
2037 td->td_proc->p_fd = fdp;
2041 * Copy a filedesc structure. A NULL pointer in returns a NULL reference,
2042 * this is to ease callers, not catch errors.
2045 fdcopy(struct filedesc *fdp)
2047 struct filedesc *newfdp;
2048 struct filedescent *nfde, *ofde;
2053 newfdp = fdinit(fdp, true);
2054 /* copy all passable descriptors (i.e. not kqueue) */
2055 newfdp->fd_freefile = -1;
2056 for (i = 0; i <= fdp->fd_lastfile; ++i) {
2057 ofde = &fdp->fd_ofiles[i];
2058 if (ofde->fde_file == NULL ||
2059 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0 ||
2060 !fhold(ofde->fde_file)) {
2061 if (newfdp->fd_freefile == -1)
2062 newfdp->fd_freefile = i;
2065 nfde = &newfdp->fd_ofiles[i];
2067 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true);
2068 fdused_init(newfdp, i);
2069 newfdp->fd_lastfile = i;
2071 if (newfdp->fd_freefile == -1)
2072 newfdp->fd_freefile = i;
2073 newfdp->fd_cmask = fdp->fd_cmask;
2074 FILEDESC_SUNLOCK(fdp);
2079 * Copies a filedesc structure, while remapping all file descriptors
2080 * stored inside using a translation table.
2082 * File descriptors are copied over to the new file descriptor table,
2083 * regardless of whether the close-on-exec flag is set.
2086 fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds,
2087 struct filedesc **ret)
2089 struct filedesc *newfdp;
2090 struct filedescent *nfde, *ofde;
2095 newfdp = fdinit(fdp, true);
2096 if (nfds > fdp->fd_lastfile + 1) {
2097 /* New table cannot be larger than the old one. */
2101 /* Copy all passable descriptors (i.e. not kqueue). */
2102 newfdp->fd_freefile = nfds;
2103 for (i = 0; i < nfds; ++i) {
2104 if (fds[i] < 0 || fds[i] > fdp->fd_lastfile) {
2105 /* File descriptor out of bounds. */
2109 ofde = &fdp->fd_ofiles[fds[i]];
2110 if (ofde->fde_file == NULL) {
2111 /* Unused file descriptor. */
2115 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) {
2116 /* File descriptor cannot be passed. */
2120 if (!fhold(nfde->fde_file)) {
2124 nfde = &newfdp->fd_ofiles[i];
2126 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true);
2127 fdused_init(newfdp, i);
2128 newfdp->fd_lastfile = i;
2130 newfdp->fd_cmask = fdp->fd_cmask;
2131 FILEDESC_SUNLOCK(fdp);
2135 FILEDESC_SUNLOCK(fdp);
2136 fdescfree_remapped(newfdp);
2141 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e.
2142 * one of processes using it exits) and the table used to be shared.
2145 fdclearlocks(struct thread *td)
2147 struct filedesc *fdp;
2148 struct filedesc_to_leader *fdtol;
2158 MPASS(fdtol != NULL);
2160 FILEDESC_XLOCK(fdp);
2161 KASSERT(fdtol->fdl_refcount > 0,
2162 ("filedesc_to_refcount botch: fdl_refcount=%d",
2163 fdtol->fdl_refcount));
2164 if (fdtol->fdl_refcount == 1 &&
2165 (p->p_leader->p_flag & P_ADVLOCK) != 0) {
2166 for (i = 0; i <= fdp->fd_lastfile; i++) {
2167 fp = fdp->fd_ofiles[i].fde_file;
2168 if (fp == NULL || fp->f_type != DTYPE_VNODE ||
2171 FILEDESC_XUNLOCK(fdp);
2172 lf.l_whence = SEEK_SET;
2175 lf.l_type = F_UNLCK;
2177 (void) VOP_ADVLOCK(vp,
2178 (caddr_t)p->p_leader, F_UNLCK,
2180 FILEDESC_XLOCK(fdp);
2185 if (fdtol->fdl_refcount == 1) {
2186 if (fdp->fd_holdleaderscount > 0 &&
2187 (p->p_leader->p_flag & P_ADVLOCK) != 0) {
2189 * close() or kern_dup() has cleared a reference
2190 * in a shared file descriptor table.
2192 fdp->fd_holdleaderswakeup = 1;
2193 sx_sleep(&fdp->fd_holdleaderscount,
2194 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0);
2197 if (fdtol->fdl_holdcount > 0) {
2199 * Ensure that fdtol->fdl_leader remains
2200 * valid in closef().
2202 fdtol->fdl_wakeup = 1;
2203 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK,
2208 fdtol->fdl_refcount--;
2209 if (fdtol->fdl_refcount == 0 &&
2210 fdtol->fdl_holdcount == 0) {
2211 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev;
2212 fdtol->fdl_prev->fdl_next = fdtol->fdl_next;
2216 FILEDESC_XUNLOCK(fdp);
2218 free(fdtol, M_FILEDESC_TO_LEADER);
2222 * Release a filedesc structure.
2225 fdescfree_fds(struct thread *td, struct filedesc *fdp, bool needclose)
2227 struct filedesc0 *fdp0;
2228 struct freetable *ft, *tft;
2229 struct filedescent *fde;
2233 for (i = 0; i <= fdp->fd_lastfile; i++) {
2234 fde = &fdp->fd_ofiles[i];
2239 (void) closef(fp, td);
2245 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE))
2246 free(fdp->fd_map, M_FILEDESC);
2247 if (fdp->fd_nfiles > NDFILE)
2248 free(fdp->fd_files, M_FILEDESC);
2250 fdp0 = (struct filedesc0 *)fdp;
2251 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft)
2252 free(ft->ft_table, M_FILEDESC);
2258 fdescfree(struct thread *td)
2261 struct filedesc *fdp;
2262 struct vnode *cdir, *jdir, *rdir;
2269 if (RACCT_ENABLED())
2270 racct_set_unlocked(p, RACCT_NOFILE, 0);
2273 if (p->p_fdtol != NULL)
2280 if (refcount_release(&fdp->fd_refcnt) == 0)
2283 FILEDESC_XLOCK(fdp);
2284 cdir = fdp->fd_cdir;
2285 fdp->fd_cdir = NULL;
2286 rdir = fdp->fd_rdir;
2287 fdp->fd_rdir = NULL;
2288 jdir = fdp->fd_jdir;
2289 fdp->fd_jdir = NULL;
2290 FILEDESC_XUNLOCK(fdp);
2299 fdescfree_fds(td, fdp, 1);
2303 fdescfree_remapped(struct filedesc *fdp)
2306 if (fdp->fd_cdir != NULL)
2307 vrele(fdp->fd_cdir);
2308 if (fdp->fd_rdir != NULL)
2309 vrele(fdp->fd_rdir);
2310 if (fdp->fd_jdir != NULL)
2311 vrele(fdp->fd_jdir);
2313 fdescfree_fds(curthread, fdp, 0);
2317 * For setugid programs, we don't want to people to use that setugidness
2318 * to generate error messages which write to a file which otherwise would
2319 * otherwise be off-limits to the process. We check for filesystems where
2320 * the vnode can change out from under us after execve (like [lin]procfs).
2322 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is
2323 * sufficient. We also don't check for setugidness since we know we are.
2326 is_unsafe(struct file *fp)
2330 if (fp->f_type != DTYPE_VNODE)
2334 return ((vp->v_vflag & VV_PROCDEP) != 0);
2338 * Make this setguid thing safe, if at all possible.
2341 fdsetugidsafety(struct thread *td)
2343 struct filedesc *fdp;
2347 fdp = td->td_proc->p_fd;
2348 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2349 MPASS(fdp->fd_nfiles >= 3);
2350 for (i = 0; i <= 2; i++) {
2351 fp = fdp->fd_ofiles[i].fde_file;
2352 if (fp != NULL && is_unsafe(fp)) {
2353 FILEDESC_XLOCK(fdp);
2354 knote_fdclose(td, i);
2356 * NULL-out descriptor prior to close to avoid
2357 * a race while close blocks.
2360 FILEDESC_XUNLOCK(fdp);
2361 (void) closef(fp, td);
2367 * If a specific file object occupies a specific file descriptor, close the
2368 * file descriptor entry and drop a reference on the file object. This is a
2369 * convenience function to handle a subsequent error in a function that calls
2370 * falloc() that handles the race that another thread might have closed the
2371 * file descriptor out from under the thread creating the file object.
2374 fdclose(struct thread *td, struct file *fp, int idx)
2376 struct filedesc *fdp = td->td_proc->p_fd;
2378 FILEDESC_XLOCK(fdp);
2379 if (fdp->fd_ofiles[idx].fde_file == fp) {
2381 FILEDESC_XUNLOCK(fdp);
2384 FILEDESC_XUNLOCK(fdp);
2388 * Close any files on exec?
2391 fdcloseexec(struct thread *td)
2393 struct filedesc *fdp;
2394 struct filedescent *fde;
2398 fdp = td->td_proc->p_fd;
2399 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2400 for (i = 0; i <= fdp->fd_lastfile; i++) {
2401 fde = &fdp->fd_ofiles[i];
2403 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE ||
2404 (fde->fde_flags & UF_EXCLOSE))) {
2405 FILEDESC_XLOCK(fdp);
2407 (void) closefp(fdp, i, fp, td, 0);
2408 FILEDESC_UNLOCK_ASSERT(fdp);
2414 * It is unsafe for set[ug]id processes to be started with file
2415 * descriptors 0..2 closed, as these descriptors are given implicit
2416 * significance in the Standard C library. fdcheckstd() will create a
2417 * descriptor referencing /dev/null for each of stdin, stdout, and
2418 * stderr that is not already open.
2421 fdcheckstd(struct thread *td)
2423 struct filedesc *fdp;
2425 int i, error, devnull;
2427 fdp = td->td_proc->p_fd;
2428 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2429 MPASS(fdp->fd_nfiles >= 3);
2431 for (i = 0; i <= 2; i++) {
2432 if (fdp->fd_ofiles[i].fde_file != NULL)
2435 save = td->td_retval[0];
2436 if (devnull != -1) {
2437 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i);
2439 error = kern_openat(td, AT_FDCWD, "/dev/null",
2440 UIO_SYSSPACE, O_RDWR, 0);
2442 devnull = td->td_retval[0];
2443 KASSERT(devnull == i, ("we didn't get our fd"));
2446 td->td_retval[0] = save;
2454 * Internal form of close. Decrement reference count on file structure.
2455 * Note: td may be NULL when closing a file that was being passed in a
2459 closef(struct file *fp, struct thread *td)
2463 struct filedesc_to_leader *fdtol;
2464 struct filedesc *fdp;
2467 * POSIX record locking dictates that any close releases ALL
2468 * locks owned by this process. This is handled by setting
2469 * a flag in the unlock to free ONLY locks obeying POSIX
2470 * semantics, and not to free BSD-style file locks.
2471 * If the descriptor was in a message, POSIX-style locks
2472 * aren't passed with the descriptor, and the thread pointer
2473 * will be NULL. Callers should be careful only to pass a
2474 * NULL thread pointer when there really is no owning
2475 * context that might have locks, or the locks will be
2478 if (fp->f_type == DTYPE_VNODE && td != NULL) {
2480 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
2481 lf.l_whence = SEEK_SET;
2484 lf.l_type = F_UNLCK;
2485 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader,
2486 F_UNLCK, &lf, F_POSIX);
2488 fdtol = td->td_proc->p_fdtol;
2489 if (fdtol != NULL) {
2491 * Handle special case where file descriptor table is
2492 * shared between multiple process leaders.
2494 fdp = td->td_proc->p_fd;
2495 FILEDESC_XLOCK(fdp);
2496 for (fdtol = fdtol->fdl_next;
2497 fdtol != td->td_proc->p_fdtol;
2498 fdtol = fdtol->fdl_next) {
2499 if ((fdtol->fdl_leader->p_flag &
2502 fdtol->fdl_holdcount++;
2503 FILEDESC_XUNLOCK(fdp);
2504 lf.l_whence = SEEK_SET;
2507 lf.l_type = F_UNLCK;
2509 (void) VOP_ADVLOCK(vp,
2510 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf,
2512 FILEDESC_XLOCK(fdp);
2513 fdtol->fdl_holdcount--;
2514 if (fdtol->fdl_holdcount == 0 &&
2515 fdtol->fdl_wakeup != 0) {
2516 fdtol->fdl_wakeup = 0;
2520 FILEDESC_XUNLOCK(fdp);
2523 return (fdrop(fp, td));
2527 * Initialize the file pointer with the specified properties.
2529 * The ops are set with release semantics to be certain that the flags, type,
2530 * and data are visible when ops is. This is to prevent ops methods from being
2531 * called with bad data.
2534 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops)
2539 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops);
2543 fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
2544 struct file **fpp, struct filecaps *havecapsp)
2546 struct filedescent *fde;
2549 FILEDESC_LOCK_ASSERT(fdp);
2551 fde = fdeget_locked(fdp, fd);
2558 error = cap_check(cap_rights_fde_inline(fde), needrightsp);
2563 if (havecapsp != NULL)
2564 filecaps_copy(&fde->fde_caps, havecapsp, true);
2566 *fpp = fde->fde_file;
2574 fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp,
2575 struct file **fpp, struct filecaps *havecapsp)
2577 struct filedesc *fdp = td->td_proc->p_fd;
2579 #ifndef CAPABILITIES
2580 error = fget_unlocked(fdp, fd, needrightsp, fpp, NULL);
2581 if (error == 0 && havecapsp != NULL)
2582 filecaps_fill(havecapsp);
2588 error = fget_unlocked(fdp, fd, needrightsp, &fp, &seq);
2592 if (havecapsp != NULL) {
2593 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps,
2594 havecapsp, false)) {
2600 if (!fd_modified(fdp, fd, seq))
2609 FILEDESC_SLOCK(fdp);
2610 error = fget_cap_locked(fdp, fd, needrightsp, fpp, havecapsp);
2611 if (error == 0 && !fhold(*fpp))
2613 FILEDESC_SUNLOCK(fdp);
2619 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
2620 struct file **fpp, seqc_t *seqp)
2623 const struct filedescent *fde;
2625 const struct fdescenttbl *fdt;
2630 cap_rights_t haverights;
2634 fdt = fdp->fd_files;
2635 if (__predict_false((u_int)fd >= fdt->fdt_nfiles))
2638 * Fetch the descriptor locklessly. We avoid fdrop() races by
2639 * never raising a refcount above 0. To accomplish this we have
2640 * to use a cmpset loop rather than an atomic_add. The descriptor
2641 * must be re-verified once we acquire a reference to be certain
2642 * that the identity is still correct and we did not lose a race
2643 * due to preemption.
2647 seq = seqc_read(fd_seqc(fdt, fd));
2648 fde = &fdt->fdt_ofiles[fd];
2649 haverights = *cap_rights_fde_inline(fde);
2651 if (!seqc_consistent(fd_seqc(fdt, fd), seq))
2654 fp = fdt->fdt_ofiles[fd].fde_file;
2659 error = cap_check(&haverights, needrightsp);
2663 count = fp->f_count;
2667 * Force a reload. Other thread could reallocate the
2668 * table before this fd was closed, so it possible that
2669 * there is a stale fp pointer in cached version.
2671 fdt = *(const struct fdescenttbl * const volatile *)
2675 if (__predict_false(count + 1 < count))
2679 * Use an acquire barrier to force re-reading of fdt so it is
2680 * refreshed for verification.
2682 if (__predict_false(atomic_fcmpset_acq_int(&fp->f_count,
2683 &count, count + 1) == 0))
2685 fdt = fdp->fd_files;
2687 if (seqc_consistent_nomb(fd_seqc(fdt, fd), seq))
2689 if (fp == fdt->fdt_ofiles[fd].fde_file)
2692 fdrop(fp, curthread);
2704 * Extract the file pointer associated with the specified descriptor for the
2705 * current user process.
2707 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is
2710 * File's rights will be checked against the capability rights mask.
2712 * If an error occurred the non-zero error is returned and *fpp is set to
2713 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is
2714 * responsible for fdrop().
2717 _fget(struct thread *td, int fd, struct file **fpp, int flags,
2718 cap_rights_t *needrightsp, seqc_t *seqp)
2720 struct filedesc *fdp;
2725 fdp = td->td_proc->p_fd;
2726 error = fget_unlocked(fdp, fd, needrightsp, &fp, seqp);
2729 if (fp->f_ops == &badfileops) {
2735 * FREAD and FWRITE failure return EBADF as per POSIX.
2741 if ((fp->f_flag & flags) == 0)
2745 if ((fp->f_flag & (FREAD | FEXEC)) == 0 ||
2746 ((fp->f_flag & FWRITE) != 0))
2752 KASSERT(0, ("wrong flags"));
2765 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
2768 return (_fget(td, fd, fpp, 0, rightsp, NULL));
2772 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp,
2776 #ifndef CAPABILITIES
2777 error = _fget(td, fd, fpp, 0, rightsp, NULL);
2778 if (maxprotp != NULL)
2779 *maxprotp = VM_PROT_ALL;
2781 cap_rights_t fdrights;
2782 struct filedesc *fdp = td->td_proc->p_fd;
2785 MPASS(cap_rights_is_set(rightsp, CAP_MMAP));
2787 error = _fget(td, fd, fpp, 0, rightsp, &seq);
2790 if (maxprotp != NULL)
2791 fdrights = *cap_rights(fdp, fd);
2792 if (!fd_modified(fdp, fd, seq))
2798 * If requested, convert capability rights to access flags.
2800 if (maxprotp != NULL)
2801 *maxprotp = cap_rights_to_vmprot(&fdrights);
2807 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
2810 return (_fget(td, fd, fpp, FREAD, rightsp, NULL));
2814 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
2817 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL));
2821 fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp, int needfcntl,
2824 struct filedesc *fdp = td->td_proc->p_fd;
2825 #ifndef CAPABILITIES
2826 return (fget_unlocked(fdp, fd, rightsp, fpp, NULL));
2831 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL));
2833 error = fget_unlocked(fdp, fd, rightsp, fpp, &seq);
2836 error = cap_fcntl_check(fdp, fd, needfcntl);
2837 if (!fd_modified(fdp, fd, seq))
2850 * Like fget() but loads the underlying vnode, or returns an error if the
2851 * descriptor does not represent a vnode. Note that pipes use vnodes but
2852 * never have VM objects. The returned vnode will be vref()'d.
2854 * XXX: what about the unused flags ?
2857 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp,
2864 error = _fget(td, fd, &fp, flags, needrightsp, NULL);
2867 if (fp->f_vnode == NULL) {
2879 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2882 return (_fgetvp(td, fd, 0, rightsp, vpp));
2886 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp,
2887 struct filecaps *havecaps, struct vnode **vpp)
2889 struct filedesc *fdp;
2890 struct filecaps caps;
2894 fdp = td->td_proc->p_fd;
2895 error = fget_cap_locked(fdp, fd, needrightsp, &fp, &caps);
2898 if (fp->f_ops == &badfileops) {
2902 if (fp->f_vnode == NULL) {
2913 filecaps_free(&caps);
2918 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2921 return (_fgetvp(td, fd, FREAD, rightsp, vpp));
2925 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2928 return (_fgetvp(td, fd, FEXEC, rightsp, vpp));
2933 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp,
2937 return (_fgetvp(td, fd, FWRITE, rightsp, vpp));
2942 * Handle the last reference to a file being closed.
2944 * Without the noinline attribute clang keeps inlining the func thorough this
2945 * file when fdrop is used.
2948 _fdrop(struct file *fp, struct thread *td)
2952 if (fp->f_count != 0)
2953 panic("fdrop: count %d", fp->f_count);
2954 error = fo_close(fp, td);
2955 atomic_subtract_int(&openfiles, 1);
2957 free(fp->f_advice, M_FADVISE);
2958 uma_zfree(file_zone, fp);
2964 * Apply an advisory lock on a file descriptor.
2966 * Just attempt to get a record lock of the requested type on the entire file
2967 * (l_whence = SEEK_SET, l_start = 0, l_len = 0).
2969 #ifndef _SYS_SYSPROTO_H_
2977 sys_flock(struct thread *td, struct flock_args *uap)
2984 error = fget(td, uap->fd, &cap_flock_rights, &fp);
2987 if (fp->f_type != DTYPE_VNODE) {
2989 return (EOPNOTSUPP);
2993 lf.l_whence = SEEK_SET;
2996 if (uap->how & LOCK_UN) {
2997 lf.l_type = F_UNLCK;
2998 atomic_clear_int(&fp->f_flag, FHASLOCK);
2999 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK);
3002 if (uap->how & LOCK_EX)
3003 lf.l_type = F_WRLCK;
3004 else if (uap->how & LOCK_SH)
3005 lf.l_type = F_RDLCK;
3010 atomic_set_int(&fp->f_flag, FHASLOCK);
3011 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
3012 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT);
3018 * Duplicate the specified descriptor to a free descriptor.
3021 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode,
3022 int openerror, int *indxp)
3024 struct filedescent *newfde, *oldfde;
3029 KASSERT(openerror == ENODEV || openerror == ENXIO,
3030 ("unexpected error %d in %s", openerror, __func__));
3033 * If the to-be-dup'd fd number is greater than the allowed number
3034 * of file descriptors, or the fd to be dup'd has already been
3035 * closed, then reject.
3037 FILEDESC_XLOCK(fdp);
3038 if ((fp = fget_locked(fdp, dfd)) == NULL) {
3039 FILEDESC_XUNLOCK(fdp);
3043 error = fdalloc(td, 0, &indx);
3045 FILEDESC_XUNLOCK(fdp);
3050 * There are two cases of interest here.
3052 * For ENODEV simply dup (dfd) to file descriptor (indx) and return.
3054 * For ENXIO steal away the file structure from (dfd) and store it in
3055 * (indx). (dfd) is effectively closed by this operation.
3057 switch (openerror) {
3060 * Check that the mode the file is being opened for is a
3061 * subset of the mode of the existing descriptor.
3063 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) {
3064 fdunused(fdp, indx);
3065 FILEDESC_XUNLOCK(fdp);
3069 fdunused(fdp, indx);
3070 FILEDESC_XUNLOCK(fdp);
3073 newfde = &fdp->fd_ofiles[indx];
3074 oldfde = &fdp->fd_ofiles[dfd];
3075 ioctls = filecaps_copy_prep(&oldfde->fde_caps);
3077 seqc_write_begin(&newfde->fde_seqc);
3079 memcpy(newfde, oldfde, fde_change_size);
3080 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps,
3083 seqc_write_end(&newfde->fde_seqc);
3088 * Steal away the file pointer from dfd and stuff it into indx.
3090 newfde = &fdp->fd_ofiles[indx];
3091 oldfde = &fdp->fd_ofiles[dfd];
3093 seqc_write_begin(&newfde->fde_seqc);
3095 memcpy(newfde, oldfde, fde_change_size);
3096 oldfde->fde_file = NULL;
3099 seqc_write_end(&newfde->fde_seqc);
3103 FILEDESC_XUNLOCK(fdp);
3109 * This sysctl determines if we will allow a process to chroot(2) if it
3110 * has a directory open:
3111 * 0: disallowed for all processes.
3112 * 1: allowed for processes that were not already chroot(2)'ed.
3113 * 2: allowed for all processes.
3116 static int chroot_allow_open_directories = 1;
3118 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW,
3119 &chroot_allow_open_directories, 0,
3120 "Allow a process to chroot(2) if it has a directory open");
3123 * Helper function for raised chroot(2) security function: Refuse if
3124 * any filedescriptors are open directories.
3127 chroot_refuse_vdir_fds(struct filedesc *fdp)
3133 FILEDESC_LOCK_ASSERT(fdp);
3135 for (fd = 0; fd <= fdp->fd_lastfile; fd++) {
3136 fp = fget_locked(fdp, fd);
3139 if (fp->f_type == DTYPE_VNODE) {
3141 if (vp->v_type == VDIR)
3149 * Common routine for kern_chroot() and jail_attach(). The caller is
3150 * responsible for invoking priv_check() and mac_vnode_check_chroot() to
3151 * authorize this operation.
3154 pwd_chroot(struct thread *td, struct vnode *vp)
3156 struct filedesc *fdp;
3157 struct vnode *oldvp;
3160 fdp = td->td_proc->p_fd;
3161 FILEDESC_XLOCK(fdp);
3162 if (chroot_allow_open_directories == 0 ||
3163 (chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) {
3164 error = chroot_refuse_vdir_fds(fdp);
3166 FILEDESC_XUNLOCK(fdp);
3170 oldvp = fdp->fd_rdir;
3173 if (fdp->fd_jdir == NULL) {
3177 FILEDESC_XUNLOCK(fdp);
3183 pwd_chdir(struct thread *td, struct vnode *vp)
3185 struct filedesc *fdp;
3186 struct vnode *oldvp;
3188 fdp = td->td_proc->p_fd;
3189 FILEDESC_XLOCK(fdp);
3190 VNASSERT(vp->v_usecount > 0, vp,
3191 ("chdir to a vnode with zero usecount"));
3192 oldvp = fdp->fd_cdir;
3194 FILEDESC_XUNLOCK(fdp);
3199 * Scan all active processes and prisons to see if any of them have a current
3200 * or root directory of `olddp'. If so, replace them with the new mount point.
3203 mountcheckdirs(struct vnode *olddp, struct vnode *newdp)
3205 struct filedesc *fdp;
3210 if (vrefcnt(olddp) == 1)
3213 sx_slock(&allproc_lock);
3214 FOREACH_PROC_IN_SYSTEM(p) {
3220 FILEDESC_XLOCK(fdp);
3221 if (fdp->fd_cdir == olddp) {
3223 fdp->fd_cdir = newdp;
3226 if (fdp->fd_rdir == olddp) {
3228 fdp->fd_rdir = newdp;
3231 if (fdp->fd_jdir == olddp) {
3233 fdp->fd_jdir = newdp;
3236 FILEDESC_XUNLOCK(fdp);
3239 sx_sunlock(&allproc_lock);
3240 if (rootvnode == olddp) {
3245 mtx_lock(&prison0.pr_mtx);
3246 if (prison0.pr_root == olddp) {
3248 prison0.pr_root = newdp;
3251 mtx_unlock(&prison0.pr_mtx);
3252 sx_slock(&allprison_lock);
3253 TAILQ_FOREACH(pr, &allprison, pr_list) {
3254 mtx_lock(&pr->pr_mtx);
3255 if (pr->pr_root == olddp) {
3257 pr->pr_root = newdp;
3260 mtx_unlock(&pr->pr_mtx);
3262 sx_sunlock(&allprison_lock);
3267 struct filedesc_to_leader *
3268 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader)
3270 struct filedesc_to_leader *fdtol;
3272 fdtol = malloc(sizeof(struct filedesc_to_leader),
3273 M_FILEDESC_TO_LEADER, M_WAITOK);
3274 fdtol->fdl_refcount = 1;
3275 fdtol->fdl_holdcount = 0;
3276 fdtol->fdl_wakeup = 0;
3277 fdtol->fdl_leader = leader;
3279 FILEDESC_XLOCK(fdp);
3280 fdtol->fdl_next = old->fdl_next;
3281 fdtol->fdl_prev = old;
3282 old->fdl_next = fdtol;
3283 fdtol->fdl_next->fdl_prev = fdtol;
3284 FILEDESC_XUNLOCK(fdp);
3286 fdtol->fdl_next = fdtol;
3287 fdtol->fdl_prev = fdtol;
3293 sysctl_kern_proc_nfds(SYSCTL_HANDLER_ARGS)
3295 struct filedesc *fdp;
3296 int i, count, slots;
3298 if (*(int *)arg1 != 0)
3301 fdp = curproc->p_fd;
3303 FILEDESC_SLOCK(fdp);
3304 slots = NDSLOTS(fdp->fd_lastfile + 1);
3305 for (i = 0; i < slots; i++)
3306 count += bitcountl(fdp->fd_map[i]);
3307 FILEDESC_SUNLOCK(fdp);
3309 return (SYSCTL_OUT(req, &count, sizeof(count)));
3312 static SYSCTL_NODE(_kern_proc, KERN_PROC_NFDS, nfds,
3313 CTLFLAG_RD|CTLFLAG_CAPRD|CTLFLAG_MPSAFE, sysctl_kern_proc_nfds,
3314 "Number of open file descriptors");
3317 * Get file structures globally.
3320 sysctl_kern_file(SYSCTL_HANDLER_ARGS)
3323 struct filedesc *fdp;
3328 error = sysctl_wire_old_buffer(req, 0);
3331 if (req->oldptr == NULL) {
3333 sx_slock(&allproc_lock);
3334 FOREACH_PROC_IN_SYSTEM(p) {
3336 if (p->p_state == PRS_NEW) {
3344 /* overestimates sparse tables. */
3345 if (fdp->fd_lastfile > 0)
3346 n += fdp->fd_lastfile;
3349 sx_sunlock(&allproc_lock);
3350 return (SYSCTL_OUT(req, 0, n * sizeof(xf)));
3353 bzero(&xf, sizeof(xf));
3354 xf.xf_size = sizeof(xf);
3355 sx_slock(&allproc_lock);
3356 FOREACH_PROC_IN_SYSTEM(p) {
3358 if (p->p_state == PRS_NEW) {
3362 if (p_cansee(req->td, p) != 0) {
3366 xf.xf_pid = p->p_pid;
3367 xf.xf_uid = p->p_ucred->cr_uid;
3372 FILEDESC_SLOCK(fdp);
3373 for (n = 0; fdp->fd_refcnt > 0 && n <= fdp->fd_lastfile; ++n) {
3374 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL)
3377 xf.xf_file = (uintptr_t)fp;
3378 xf.xf_data = (uintptr_t)fp->f_data;
3379 xf.xf_vnode = (uintptr_t)fp->f_vnode;
3380 xf.xf_type = (uintptr_t)fp->f_type;
3381 xf.xf_count = fp->f_count;
3383 xf.xf_offset = foffset_get(fp);
3384 xf.xf_flag = fp->f_flag;
3385 error = SYSCTL_OUT(req, &xf, sizeof(xf));
3389 FILEDESC_SUNLOCK(fdp);
3394 sx_sunlock(&allproc_lock);
3398 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
3399 0, 0, sysctl_kern_file, "S,xfile", "Entire file table");
3401 #ifdef KINFO_FILE_SIZE
3402 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
3406 xlate_fflags(int fflags)
3408 static const struct {
3411 } fflags_table[] = {
3412 { FAPPEND, KF_FLAG_APPEND },
3413 { FASYNC, KF_FLAG_ASYNC },
3414 { FFSYNC, KF_FLAG_FSYNC },
3415 { FHASLOCK, KF_FLAG_HASLOCK },
3416 { FNONBLOCK, KF_FLAG_NONBLOCK },
3417 { FREAD, KF_FLAG_READ },
3418 { FWRITE, KF_FLAG_WRITE },
3419 { O_CREAT, KF_FLAG_CREAT },
3420 { O_DIRECT, KF_FLAG_DIRECT },
3421 { O_EXCL, KF_FLAG_EXCL },
3422 { O_EXEC, KF_FLAG_EXEC },
3423 { O_EXLOCK, KF_FLAG_EXLOCK },
3424 { O_NOFOLLOW, KF_FLAG_NOFOLLOW },
3425 { O_SHLOCK, KF_FLAG_SHLOCK },
3426 { O_TRUNC, KF_FLAG_TRUNC }
3432 for (i = 0; i < nitems(fflags_table); i++)
3433 if (fflags & fflags_table[i].fflag)
3434 kflags |= fflags_table[i].kf_fflag;
3438 /* Trim unused data from kf_path by truncating the structure size. */
3440 pack_kinfo(struct kinfo_file *kif)
3443 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) +
3444 strlen(kif->kf_path) + 1;
3445 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t));
3449 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp,
3450 struct kinfo_file *kif, struct filedesc *fdp, int flags)
3454 bzero(kif, sizeof(*kif));
3456 /* Set a default type to allow for empty fill_kinfo() methods. */
3457 kif->kf_type = KF_TYPE_UNKNOWN;
3458 kif->kf_flags = xlate_fflags(fp->f_flag);
3459 if (rightsp != NULL)
3460 kif->kf_cap_rights = *rightsp;
3462 cap_rights_init(&kif->kf_cap_rights);
3464 kif->kf_ref_count = fp->f_count;
3465 kif->kf_offset = foffset_get(fp);
3468 * This may drop the filedesc lock, so the 'fp' cannot be
3469 * accessed after this call.
3471 error = fo_fill_kinfo(fp, kif, fdp);
3473 kif->kf_status |= KF_ATTR_VALID;
3474 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0)
3477 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t));
3481 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags,
3482 struct kinfo_file *kif, int flags)
3486 bzero(kif, sizeof(*kif));
3488 kif->kf_type = KF_TYPE_VNODE;
3489 error = vn_fill_kinfo_vnode(vp, kif);
3491 kif->kf_status |= KF_ATTR_VALID;
3492 kif->kf_flags = xlate_fflags(fflags);
3493 cap_rights_init(&kif->kf_cap_rights);
3495 kif->kf_ref_count = -1;
3496 kif->kf_offset = -1;
3497 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0)
3500 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t));
3504 struct export_fd_buf {
3505 struct filedesc *fdp;
3508 struct kinfo_file kif;
3513 export_kinfo_to_sb(struct export_fd_buf *efbuf)
3515 struct kinfo_file *kif;
3518 if (efbuf->remainder != -1) {
3519 if (efbuf->remainder < kif->kf_structsize) {
3520 /* Terminate export. */
3521 efbuf->remainder = 0;
3524 efbuf->remainder -= kif->kf_structsize;
3526 return (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) == 0 ? 0 : ENOMEM);
3530 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp,
3531 struct export_fd_buf *efbuf)
3535 if (efbuf->remainder == 0)
3537 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp,
3539 FILEDESC_SUNLOCK(efbuf->fdp);
3540 error = export_kinfo_to_sb(efbuf);
3541 FILEDESC_SLOCK(efbuf->fdp);
3546 export_vnode_to_sb(struct vnode *vp, int fd, int fflags,
3547 struct export_fd_buf *efbuf)
3551 if (efbuf->remainder == 0)
3553 if (efbuf->fdp != NULL)
3554 FILEDESC_SUNLOCK(efbuf->fdp);
3555 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif, efbuf->flags);
3556 error = export_kinfo_to_sb(efbuf);
3557 if (efbuf->fdp != NULL)
3558 FILEDESC_SLOCK(efbuf->fdp);
3563 * Store a process file descriptor information to sbuf.
3565 * Takes a locked proc as argument, and returns with the proc unlocked.
3568 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen,
3572 struct filedesc *fdp;
3573 struct export_fd_buf *efbuf;
3574 struct vnode *cttyvp, *textvp, *tracevp;
3576 cap_rights_t rights;
3578 PROC_LOCK_ASSERT(p, MA_OWNED);
3581 tracevp = p->p_tracevp;
3582 if (tracevp != NULL)
3585 textvp = p->p_textvp;
3588 /* Controlling tty. */
3590 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) {
3591 cttyvp = p->p_pgrp->pg_session->s_ttyvp;
3597 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK);
3600 efbuf->remainder = maxlen;
3601 efbuf->flags = flags;
3602 if (tracevp != NULL)
3603 export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE, FREAD | FWRITE,
3606 export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD, efbuf);
3608 export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY, FREAD | FWRITE,
3614 FILEDESC_SLOCK(fdp);
3615 /* working directory */
3616 if (fdp->fd_cdir != NULL) {
3617 vrefact(fdp->fd_cdir);
3618 export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD, FREAD, efbuf);
3620 /* root directory */
3621 if (fdp->fd_rdir != NULL) {
3622 vrefact(fdp->fd_rdir);
3623 export_vnode_to_sb(fdp->fd_rdir, KF_FD_TYPE_ROOT, FREAD, efbuf);
3625 /* jail directory */
3626 if (fdp->fd_jdir != NULL) {
3627 vrefact(fdp->fd_jdir);
3628 export_vnode_to_sb(fdp->fd_jdir, KF_FD_TYPE_JAIL, FREAD, efbuf);
3630 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) {
3631 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL)
3634 rights = *cap_rights(fdp, i);
3635 #else /* !CAPABILITIES */
3636 rights = cap_no_rights;
3639 * Create sysctl entry. It is OK to drop the filedesc
3640 * lock inside of export_file_to_sb() as we will
3641 * re-validate and re-evaluate its properties when the
3644 error = export_file_to_sb(fp, i, &rights, efbuf);
3645 if (error != 0 || efbuf->remainder == 0)
3648 FILEDESC_SUNLOCK(fdp);
3651 free(efbuf, M_TEMP);
3655 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5)
3658 * Get per-process file descriptors for use by procstat(1), et al.
3661 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS)
3666 int error, error2, *name;
3670 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req);
3671 sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
3672 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p);
3677 maxlen = req->oldptr != NULL ? req->oldlen : -1;
3678 error = kern_proc_filedesc_out(p, &sb, maxlen,
3679 KERN_FILEDESC_PACK_KINFO);
3680 error2 = sbuf_finish(&sb);
3682 return (error != 0 ? error : error2);
3685 #ifdef COMPAT_FREEBSD7
3686 #ifdef KINFO_OFILE_SIZE
3687 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE);
3691 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif)
3694 okif->kf_structsize = sizeof(*okif);
3695 okif->kf_type = kif->kf_type;
3696 okif->kf_fd = kif->kf_fd;
3697 okif->kf_ref_count = kif->kf_ref_count;
3698 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE |
3699 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK |
3700 KF_FLAG_DIRECT | KF_FLAG_HASLOCK);
3701 okif->kf_offset = kif->kf_offset;
3702 if (kif->kf_type == KF_TYPE_VNODE)
3703 okif->kf_vnode_type = kif->kf_un.kf_file.kf_file_type;
3705 okif->kf_vnode_type = KF_VTYPE_VNON;
3706 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path));
3707 if (kif->kf_type == KF_TYPE_SOCKET) {
3708 okif->kf_sock_domain = kif->kf_un.kf_sock.kf_sock_domain0;
3709 okif->kf_sock_type = kif->kf_un.kf_sock.kf_sock_type0;
3710 okif->kf_sock_protocol = kif->kf_un.kf_sock.kf_sock_protocol0;
3711 okif->kf_sa_local = kif->kf_un.kf_sock.kf_sa_local;
3712 okif->kf_sa_peer = kif->kf_un.kf_sock.kf_sa_peer;
3714 okif->kf_sa_local.ss_family = AF_UNSPEC;
3715 okif->kf_sa_peer.ss_family = AF_UNSPEC;
3720 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif,
3721 struct kinfo_ofile *okif, struct filedesc *fdp, struct sysctl_req *req)
3726 FILEDESC_SUNLOCK(fdp);
3727 export_vnode_to_kinfo(vp, type, 0, kif, KERN_FILEDESC_PACK_KINFO);
3728 kinfo_to_okinfo(kif, okif);
3729 error = SYSCTL_OUT(req, okif, sizeof(*okif));
3730 FILEDESC_SLOCK(fdp);
3735 * Get per-process file descriptors for use by procstat(1), et al.
3738 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS)
3740 struct kinfo_ofile *okif;
3741 struct kinfo_file *kif;
3742 struct filedesc *fdp;
3743 int error, i, *name;
3748 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p);
3755 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK);
3756 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK);
3757 FILEDESC_SLOCK(fdp);
3758 if (fdp->fd_cdir != NULL)
3759 export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif,
3761 if (fdp->fd_rdir != NULL)
3762 export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif,
3764 if (fdp->fd_jdir != NULL)
3765 export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif,
3767 for (i = 0; fdp->fd_refcnt > 0 && i <= fdp->fd_lastfile; i++) {
3768 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL)
3770 export_file_to_kinfo(fp, i, NULL, kif, fdp,
3771 KERN_FILEDESC_PACK_KINFO);
3772 FILEDESC_SUNLOCK(fdp);
3773 kinfo_to_okinfo(kif, okif);
3774 error = SYSCTL_OUT(req, okif, sizeof(*okif));
3775 FILEDESC_SLOCK(fdp);
3779 FILEDESC_SUNLOCK(fdp);
3786 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc,
3787 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc,
3788 "Process ofiledesc entries");
3789 #endif /* COMPAT_FREEBSD7 */
3792 vntype_to_kinfo(int vtype)
3797 } vtypes_table[] = {
3798 { VBAD, KF_VTYPE_VBAD },
3799 { VBLK, KF_VTYPE_VBLK },
3800 { VCHR, KF_VTYPE_VCHR },
3801 { VDIR, KF_VTYPE_VDIR },
3802 { VFIFO, KF_VTYPE_VFIFO },
3803 { VLNK, KF_VTYPE_VLNK },
3804 { VNON, KF_VTYPE_VNON },
3805 { VREG, KF_VTYPE_VREG },
3806 { VSOCK, KF_VTYPE_VSOCK }
3811 * Perform vtype translation.
3813 for (i = 0; i < nitems(vtypes_table); i++)
3814 if (vtypes_table[i].vtype == vtype)
3815 return (vtypes_table[i].kf_vtype);
3817 return (KF_VTYPE_UNKNOWN);
3820 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc,
3821 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc,
3822 "Process filedesc entries");
3825 * Store a process current working directory information to sbuf.
3827 * Takes a locked proc as argument, and returns with the proc unlocked.
3830 kern_proc_cwd_out(struct proc *p, struct sbuf *sb, ssize_t maxlen)
3832 struct filedesc *fdp;
3833 struct export_fd_buf *efbuf;
3836 PROC_LOCK_ASSERT(p, MA_OWNED);
3843 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK);
3846 efbuf->remainder = maxlen;
3848 FILEDESC_SLOCK(fdp);
3849 if (fdp->fd_cdir == NULL)
3852 vrefact(fdp->fd_cdir);
3853 error = export_vnode_to_sb(fdp->fd_cdir, KF_FD_TYPE_CWD,
3856 FILEDESC_SUNLOCK(fdp);
3858 free(efbuf, M_TEMP);
3863 * Get per-process current working directory.
3866 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS)
3871 int error, error2, *name;
3875 sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file), req);
3876 sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
3877 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p);
3882 maxlen = req->oldptr != NULL ? req->oldlen : -1;
3883 error = kern_proc_cwd_out(p, &sb, maxlen);
3884 error2 = sbuf_finish(&sb);
3886 return (error != 0 ? error : error2);
3889 static SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD|CTLFLAG_MPSAFE,
3890 sysctl_kern_proc_cwd, "Process current working directory");
3894 * For the purposes of debugging, generate a human-readable string for the
3898 file_type_to_name(short type)
3926 case DTYPE_PROCDESC:
3928 case DTYPE_LINUXEFD:
3930 case DTYPE_LINUXTFD:
3938 * For the purposes of debugging, identify a process (if any, perhaps one of
3939 * many) that references the passed file in its file descriptor array. Return
3942 static struct proc *
3943 file_to_first_proc(struct file *fp)
3945 struct filedesc *fdp;
3949 FOREACH_PROC_IN_SYSTEM(p) {
3950 if (p->p_state == PRS_NEW)
3955 for (n = 0; n <= fdp->fd_lastfile; n++) {
3956 if (fp == fdp->fd_ofiles[n].fde_file)
3964 db_print_file(struct file *fp, int header)
3966 #define XPTRWIDTH ((int)howmany(sizeof(void *) * NBBY, 4))
3970 db_printf("%*s %6s %*s %8s %4s %5s %6s %*s %5s %s\n",
3971 XPTRWIDTH, "File", "Type", XPTRWIDTH, "Data", "Flag",
3972 "GCFl", "Count", "MCount", XPTRWIDTH, "Vnode", "FPID",
3974 p = file_to_first_proc(fp);
3975 db_printf("%*p %6s %*p %08x %04x %5d %6d %*p %5d %s\n", XPTRWIDTH,
3976 fp, file_type_to_name(fp->f_type), XPTRWIDTH, fp->f_data,
3977 fp->f_flag, 0, fp->f_count, 0, XPTRWIDTH, fp->f_vnode,
3978 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-");
3983 DB_SHOW_COMMAND(file, db_show_file)
3988 db_printf("usage: show file <addr>\n");
3991 fp = (struct file *)addr;
3992 db_print_file(fp, 1);
3995 DB_SHOW_COMMAND(files, db_show_files)
3997 struct filedesc *fdp;
4004 FOREACH_PROC_IN_SYSTEM(p) {
4005 if (p->p_state == PRS_NEW)
4007 if ((fdp = p->p_fd) == NULL)
4009 for (n = 0; n <= fdp->fd_lastfile; ++n) {
4010 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL)
4012 db_print_file(fp, header);
4019 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW,
4020 &maxfilesperproc, 0, "Maximum files allowed open per process");
4022 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW,
4023 &maxfiles, 0, "Maximum number of files");
4025 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD,
4026 __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files");
4030 filelistinit(void *dummy)
4033 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL,
4034 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
4035 filedesc0_zone = uma_zcreate("filedesc0", sizeof(struct filedesc0),
4036 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
4037 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF);
4039 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL);
4041 /*-------------------------------------------------------------------*/
4044 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred,
4045 int flags, struct thread *td)
4052 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
4060 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
4068 badfo_poll(struct file *fp, int events, struct ucred *active_cred,
4076 badfo_kqfilter(struct file *fp, struct knote *kn)
4083 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
4091 badfo_close(struct file *fp, struct thread *td)
4098 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
4106 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
4114 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
4115 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
4123 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
4129 struct fileops badfileops = {
4130 .fo_read = badfo_readwrite,
4131 .fo_write = badfo_readwrite,
4132 .fo_truncate = badfo_truncate,
4133 .fo_ioctl = badfo_ioctl,
4134 .fo_poll = badfo_poll,
4135 .fo_kqfilter = badfo_kqfilter,
4136 .fo_stat = badfo_stat,
4137 .fo_close = badfo_close,
4138 .fo_chmod = badfo_chmod,
4139 .fo_chown = badfo_chown,
4140 .fo_sendfile = badfo_sendfile,
4141 .fo_fill_kinfo = badfo_fill_kinfo,
4145 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred,
4146 int flags, struct thread *td)
4149 return (EOPNOTSUPP);
4153 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
4161 invfo_ioctl(struct file *fp, u_long com, void *data,
4162 struct ucred *active_cred, struct thread *td)
4169 invfo_poll(struct file *fp, int events, struct ucred *active_cred,
4173 return (poll_no_poll(events));
4177 invfo_kqfilter(struct file *fp, struct knote *kn)
4184 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
4192 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
4200 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
4201 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
4208 /*-------------------------------------------------------------------*/
4211 * File Descriptor pseudo-device driver (/dev/fd/).
4213 * Opening minor device N dup()s the file (if any) connected to file
4214 * descriptor N belonging to the calling process. Note that this driver
4215 * consists of only the ``open()'' routine, because all subsequent
4216 * references to this file will be direct to the other driver.
4218 * XXX: we could give this one a cloning event handler if necessary.
4223 fdopen(struct cdev *dev, int mode, int type, struct thread *td)
4227 * XXX Kludge: set curthread->td_dupfd to contain the value of the
4228 * the file descriptor being sought for duplication. The error
4229 * return ensures that the vnode for this device will be released
4230 * by vn_open. Open will detect this special error and take the
4231 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN
4232 * will simply report the error.
4234 td->td_dupfd = dev2unit(dev);
4238 static struct cdevsw fildesc_cdevsw = {
4239 .d_version = D_VERSION,
4245 fildesc_drvinit(void *unused)
4249 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL,
4250 UID_ROOT, GID_WHEEL, 0666, "fd/0");
4251 make_dev_alias(dev, "stdin");
4252 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL,
4253 UID_ROOT, GID_WHEEL, 0666, "fd/1");
4254 make_dev_alias(dev, "stdout");
4255 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL,
4256 UID_ROOT, GID_WHEEL, 0666, "fd/2");
4257 make_dev_alias(dev, "stderr");
4260 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL);