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
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9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
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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)
265 fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles);
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 seq_write_begin(&fde->fde_seq);
309 fde->fde_file = NULL;
311 seq_write_end(&fde->fde_seq);
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)
352 min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc);
354 PROC_LOCK(td->td_proc);
355 lim = racct_get_limit(td->td_proc, RACCT_NOFILE);
356 PROC_UNLOCK(td->td_proc);
357 if (lim < td->td_retval[0])
358 td->td_retval[0] = lim;
364 * Duplicate a file descriptor to a particular value.
366 * Note: keep in mind that a potential race condition exists when closing
367 * descriptors from a shared descriptor table (via rfork).
369 #ifndef _SYS_SYSPROTO_H_
377 sys_dup2(struct thread *td, struct dup2_args *uap)
380 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to));
384 * Duplicate a file descriptor.
386 #ifndef _SYS_SYSPROTO_H_
393 sys_dup(struct thread *td, struct dup_args *uap)
396 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0));
400 * The file control system call.
402 #ifndef _SYS_SYSPROTO_H_
411 sys_fcntl(struct thread *td, struct fcntl_args *uap)
414 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg));
418 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg)
432 * Convert old flock structure to new.
434 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl));
435 fl.l_start = ofl.l_start;
436 fl.l_len = ofl.l_len;
437 fl.l_pid = ofl.l_pid;
438 fl.l_type = ofl.l_type;
439 fl.l_whence = ofl.l_whence;
453 arg1 = (intptr_t)&fl;
459 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl));
460 arg1 = (intptr_t)&fl;
468 error = kern_fcntl(td, fd, newcmd, arg1);
471 if (cmd == F_OGETLK) {
472 ofl.l_start = fl.l_start;
473 ofl.l_len = fl.l_len;
474 ofl.l_pid = fl.l_pid;
475 ofl.l_type = fl.l_type;
476 ofl.l_whence = fl.l_whence;
477 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl));
478 } else if (cmd == F_GETLK) {
479 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl));
485 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg)
487 struct filedesc *fdp;
489 struct file *fp, *fp2;
490 struct filedescent *fde;
508 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp);
511 case F_DUPFD_CLOEXEC:
513 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp);
518 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp);
521 case F_DUP2FD_CLOEXEC:
523 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp);
529 fde = fdeget_locked(fdp, fd);
532 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0;
535 FILEDESC_SUNLOCK(fdp);
541 fde = fdeget_locked(fdp, fd);
543 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) |
544 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0);
547 FILEDESC_XUNLOCK(fdp);
551 error = fget_fcntl(td, fd,
552 cap_rights_init(&rights, CAP_FCNTL), F_GETFL, &fp);
555 td->td_retval[0] = OFLAGS(fp->f_flag);
560 error = fget_fcntl(td, fd,
561 cap_rights_init(&rights, CAP_FCNTL), F_SETFL, &fp);
565 tmp = flg = fp->f_flag;
567 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS;
568 } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0);
569 tmp = fp->f_flag & FNONBLOCK;
570 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
575 tmp = fp->f_flag & FASYNC;
576 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td);
581 atomic_clear_int(&fp->f_flag, FNONBLOCK);
583 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
588 error = fget_fcntl(td, fd,
589 cap_rights_init(&rights, CAP_FCNTL), F_GETOWN, &fp);
592 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td);
594 td->td_retval[0] = tmp;
599 error = fget_fcntl(td, fd,
600 cap_rights_init(&rights, CAP_FCNTL), F_SETOWN, &fp);
604 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td);
609 error = priv_check(td, PRIV_NFS_LOCKD);
617 /* FALLTHROUGH F_SETLK */
621 cap_rights_init(&rights, CAP_FLOCK);
622 error = fget_unlocked(fdp, fd, &rights, &fp, NULL);
625 if (fp->f_type != DTYPE_VNODE) {
631 flp = (struct flock *)arg;
632 if (flp->l_whence == SEEK_CUR) {
633 foffset = foffset_get(fp);
636 foffset > OFF_MAX - flp->l_start)) {
641 flp->l_start += foffset;
645 switch (flp->l_type) {
647 if ((fp->f_flag & FREAD) == 0) {
651 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) {
652 PROC_LOCK(p->p_leader);
653 p->p_leader->p_flag |= P_ADVLOCK;
654 PROC_UNLOCK(p->p_leader);
656 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
660 if ((fp->f_flag & FWRITE) == 0) {
664 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) {
665 PROC_LOCK(p->p_leader);
666 p->p_leader->p_flag |= P_ADVLOCK;
667 PROC_UNLOCK(p->p_leader);
669 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
673 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK,
678 * Temporary api for testing remote lock
681 if (flg != F_REMOTE) {
685 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
686 F_UNLCKSYS, flp, flg);
692 if (error != 0 || flp->l_type == F_UNLCK ||
693 flp->l_type == F_UNLCKSYS) {
699 * Check for a race with close.
701 * The vnode is now advisory locked (or unlocked, but this case
702 * is not really important) as the caller requested.
703 * We had to drop the filedesc lock, so we need to recheck if
704 * the descriptor is still valid, because if it was closed
705 * in the meantime we need to remove advisory lock from the
706 * vnode - close on any descriptor leading to an advisory
707 * locked vnode, removes that lock.
708 * We will return 0 on purpose in that case, as the result of
709 * successful advisory lock might have been externally visible
710 * already. This is fine - effectively we pretend to the caller
711 * that the closing thread was a bit slower and that the
712 * advisory lock succeeded before the close.
714 error = fget_unlocked(fdp, fd, &rights, &fp2, NULL);
720 flp->l_whence = SEEK_SET;
723 flp->l_type = F_UNLCK;
724 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
725 F_UNLCK, flp, F_POSIX);
732 error = fget_unlocked(fdp, fd,
733 cap_rights_init(&rights, CAP_FLOCK), &fp, NULL);
736 if (fp->f_type != DTYPE_VNODE) {
741 flp = (struct flock *)arg;
742 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK &&
743 flp->l_type != F_UNLCK) {
748 if (flp->l_whence == SEEK_CUR) {
749 foffset = foffset_get(fp);
750 if ((flp->l_start > 0 &&
751 foffset > OFF_MAX - flp->l_start) ||
753 foffset < OFF_MIN - flp->l_start)) {
758 flp->l_start += foffset;
761 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp,
767 arg = arg ? 128 * 1024: 0;
770 error = fget_unlocked(fdp, fd,
771 cap_rights_init(&rights), &fp, NULL);
774 if (fp->f_type != DTYPE_VNODE) {
781 * Exclusive lock synchronizes against f_seqcount reads and
782 * writes in sequential_heuristic().
784 error = vn_lock(vp, LK_EXCLUSIVE);
790 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize;
791 fp->f_seqcount = (arg + bsize - 1) / bsize;
792 atomic_set_int(&fp->f_flag, FRDAHEAD);
794 atomic_clear_int(&fp->f_flag, FRDAHEAD);
808 getmaxfd(struct thread *td)
811 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc));
815 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD).
818 kern_dup(struct thread *td, u_int mode, int flags, int old, int new)
820 struct filedesc *fdp;
821 struct filedescent *oldfde, *newfde;
824 u_long *oioctls, *nioctls;
830 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0);
831 MPASS(mode < FDDUP_LASTMODE);
834 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */
837 * Verify we have a valid descriptor to dup from and possibly to
838 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should
839 * return EINVAL when the new descriptor is out of bounds.
844 return (mode == FDDUP_FCNTL ? EINVAL : EBADF);
845 maxfd = getmaxfd(td);
847 return (mode == FDDUP_FCNTL ? EINVAL : EBADF);
851 if (fget_locked(fdp, old) == NULL)
853 if ((mode == FDDUP_FIXED || mode == FDDUP_MUSTREPLACE) && old == new) {
854 td->td_retval[0] = new;
855 if (flags & FDDUP_FLAG_CLOEXEC)
856 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE;
862 * If the caller specified a file descriptor, make sure the file
863 * table is large enough to hold it, and grab it. Otherwise, just
864 * allocate a new descriptor the usual way.
869 if ((error = fdalloc(td, new, &new)) != 0)
872 case FDDUP_MUSTREPLACE:
873 /* Target file descriptor must exist. */
874 if (fget_locked(fdp, new) == NULL)
878 if (new >= fdp->fd_nfiles) {
880 * The resource limits are here instead of e.g.
881 * fdalloc(), because the file descriptor table may be
882 * shared between processes, so we can't really use
883 * racct_add()/racct_sub(). Instead of counting the
884 * number of actually allocated descriptors, just put
885 * the limit on the size of the file descriptor table.
890 error = racct_set(p, RACCT_NOFILE, new + 1);
898 fdgrowtable_exp(fdp, new + 1);
900 if (!fdisused(fdp, new))
904 KASSERT(0, ("%s unsupported mode %d", __func__, mode));
907 KASSERT(old != new, ("new fd is same as old"));
909 oldfde = &fdp->fd_ofiles[old];
910 fhold(oldfde->fde_file);
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 seq_write_begin(&newfde->fde_seq);
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 seq_write_end(&newfde->fde_seq);
933 filecaps_free_finish(oioctls);
934 td->td_retval[0] = new;
939 (void) closefp(fdp, new, delfp, td, 1);
940 FILEDESC_UNLOCK_ASSERT(fdp);
943 FILEDESC_XUNLOCK(fdp);
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).
1160 struct sigio **sigiop;
1165 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0;
1171 * Function drops the filedesc lock on return.
1174 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td,
1179 FILEDESC_XLOCK_ASSERT(fdp);
1182 if (td->td_proc->p_fdtol != NULL) {
1184 * Ask fdfree() to sleep to ensure that all relevant
1185 * process leaders can be traversed in closef().
1187 fdp->fd_holdleaderscount++;
1194 * We now hold the fp reference that used to be owned by the
1195 * descriptor array. We have to unlock the FILEDESC *AFTER*
1196 * knote_fdclose to prevent a race of the fd getting opened, a knote
1197 * added, and deleteing a knote for the new fd.
1199 knote_fdclose(td, fd);
1202 * We need to notify mqueue if the object is of type mqueue.
1204 if (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)
1366 cap_rights_t rights;
1371 error = fget(td, fd, cap_rights_init(&rights, CAP_FSTAT), &fp);
1375 AUDIT_ARG_FILE(td->td_proc, fp);
1377 error = fo_stat(fp, sbp, td->td_ucred, td);
1379 #ifdef __STAT_TIME_T_EXT
1381 sbp->st_atim_ext = 0;
1382 sbp->st_mtim_ext = 0;
1383 sbp->st_ctim_ext = 0;
1384 sbp->st_btim_ext = 0;
1388 if (error == 0 && KTRPOINT(td, KTR_STRUCT))
1394 #if defined(COMPAT_FREEBSD11)
1396 * Return status information about a file descriptor.
1398 #ifndef _SYS_SYSPROTO_H_
1399 struct freebsd11_nfstat_args {
1406 freebsd11_nfstat(struct thread *td, struct freebsd11_nfstat_args *uap)
1412 error = kern_fstat(td, uap->fd, &ub);
1414 freebsd11_cvtnstat(&ub, &nub);
1415 error = copyout(&nub, uap->sb, sizeof(nub));
1419 #endif /* COMPAT_FREEBSD11 */
1422 * Return pathconf information about a file descriptor.
1424 #ifndef _SYS_SYSPROTO_H_
1425 struct fpathconf_args {
1432 sys_fpathconf(struct thread *td, struct fpathconf_args *uap)
1437 error = kern_fpathconf(td, uap->fd, uap->name, &value);
1439 td->td_retval[0] = value;
1444 kern_fpathconf(struct thread *td, int fd, int name, long *valuep)
1448 cap_rights_t rights;
1451 error = fget(td, fd, cap_rights_init(&rights, CAP_FPATHCONF), &fp);
1455 if (name == _PC_ASYNC_IO) {
1456 *valuep = _POSIX_ASYNCHRONOUS_IO;
1461 vn_lock(vp, LK_SHARED | LK_RETRY);
1462 error = VOP_PATHCONF(vp, name, valuep);
1464 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) {
1465 if (name != _PC_PIPE_BUF) {
1480 * Initialize filecaps structure.
1483 filecaps_init(struct filecaps *fcaps)
1486 bzero(fcaps, sizeof(*fcaps));
1487 fcaps->fc_nioctls = -1;
1491 * Copy filecaps structure allocating memory for ioctls array if needed.
1493 * The last parameter indicates whether the fdtable is locked. If it is not and
1494 * ioctls are encountered, copying fails and the caller must lock the table.
1496 * Note that if the table was not locked, the caller has to check the relevant
1497 * sequence counter to determine whether the operation was successful.
1500 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked)
1504 if (src->fc_ioctls != NULL && !locked)
1507 if (src->fc_ioctls == NULL)
1510 KASSERT(src->fc_nioctls > 0,
1511 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1513 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1514 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1515 bcopy(src->fc_ioctls, dst->fc_ioctls, size);
1520 filecaps_copy_prep(const struct filecaps *src)
1525 if (src->fc_ioctls == NULL)
1528 KASSERT(src->fc_nioctls > 0,
1529 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1531 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1532 ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1537 filecaps_copy_finish(const struct filecaps *src, struct filecaps *dst,
1543 if (src->fc_ioctls == NULL) {
1544 MPASS(ioctls == NULL);
1548 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1549 dst->fc_ioctls = ioctls;
1550 bcopy(src->fc_ioctls, dst->fc_ioctls, size);
1554 * Move filecaps structure to the new place and clear the old place.
1557 filecaps_move(struct filecaps *src, struct filecaps *dst)
1561 bzero(src, sizeof(*src));
1565 * Fill the given filecaps structure with full rights.
1568 filecaps_fill(struct filecaps *fcaps)
1571 CAP_ALL(&fcaps->fc_rights);
1572 fcaps->fc_ioctls = NULL;
1573 fcaps->fc_nioctls = -1;
1574 fcaps->fc_fcntls = CAP_FCNTL_ALL;
1578 * Free memory allocated within filecaps structure.
1581 filecaps_free(struct filecaps *fcaps)
1584 free(fcaps->fc_ioctls, M_FILECAPS);
1585 bzero(fcaps, sizeof(*fcaps));
1589 filecaps_free_prep(struct filecaps *fcaps)
1593 ioctls = fcaps->fc_ioctls;
1594 bzero(fcaps, sizeof(*fcaps));
1599 filecaps_free_finish(u_long *ioctls)
1602 free(ioctls, M_FILECAPS);
1606 * Validate the given filecaps structure.
1609 filecaps_validate(const struct filecaps *fcaps, const char *func)
1612 KASSERT(cap_rights_is_valid(&fcaps->fc_rights),
1613 ("%s: invalid rights", func));
1614 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0,
1615 ("%s: invalid fcntls", func));
1616 KASSERT(fcaps->fc_fcntls == 0 ||
1617 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL),
1618 ("%s: fcntls without CAP_FCNTL", func));
1619 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 :
1620 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0),
1621 ("%s: invalid ioctls", func));
1622 KASSERT(fcaps->fc_nioctls == 0 ||
1623 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL),
1624 ("%s: ioctls without CAP_IOCTL", func));
1628 fdgrowtable_exp(struct filedesc *fdp, int nfd)
1632 FILEDESC_XLOCK_ASSERT(fdp);
1634 nfd1 = fdp->fd_nfiles * 2;
1637 fdgrowtable(fdp, nfd1);
1641 * Grow the file table to accommodate (at least) nfd descriptors.
1644 fdgrowtable(struct filedesc *fdp, int nfd)
1646 struct filedesc0 *fdp0;
1647 struct freetable *ft;
1648 struct fdescenttbl *ntable;
1649 struct fdescenttbl *otable;
1650 int nnfiles, onfiles;
1651 NDSLOTTYPE *nmap, *omap;
1654 * If lastfile is -1 this struct filedesc was just allocated and we are
1655 * growing it to accommodate for the one we are going to copy from. There
1656 * is no need to have a lock on this one as it's not visible to anyone.
1658 if (fdp->fd_lastfile != -1)
1659 FILEDESC_XLOCK_ASSERT(fdp);
1661 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table"));
1663 /* save old values */
1664 onfiles = fdp->fd_nfiles;
1665 otable = fdp->fd_files;
1668 /* compute the size of the new table */
1669 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */
1670 if (nnfiles <= onfiles)
1671 /* the table is already large enough */
1675 * Allocate a new table. We need enough space for the number of
1676 * entries, file entries themselves and the struct freetable we will use
1677 * when we decommission the table and place it on the freelist.
1678 * We place the struct freetable in the middle so we don't have
1679 * to worry about padding.
1681 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) +
1682 nnfiles * sizeof(ntable->fdt_ofiles[0]) +
1683 sizeof(struct freetable),
1684 M_FILEDESC, M_ZERO | M_WAITOK);
1685 /* copy the old data */
1686 ntable->fdt_nfiles = nnfiles;
1687 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles,
1688 onfiles * sizeof(ntable->fdt_ofiles[0]));
1691 * Allocate a new map only if the old is not large enough. It will
1692 * grow at a slower rate than the table as it can map more
1693 * entries than the table can hold.
1695 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) {
1696 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC,
1698 /* copy over the old data and update the pointer */
1699 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap));
1704 * Make sure that ntable is correctly initialized before we replace
1705 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent
1708 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable);
1711 * Do not free the old file table, as some threads may still
1712 * reference entries within it. Instead, place it on a freelist
1713 * which will be processed when the struct filedesc is released.
1715 * Note that if onfiles == NDFILE, we're dealing with the original
1716 * static allocation contained within (struct filedesc0 *)fdp,
1717 * which must not be freed.
1719 if (onfiles > NDFILE) {
1720 ft = (struct freetable *)&otable->fdt_ofiles[onfiles];
1721 fdp0 = (struct filedesc0 *)fdp;
1722 ft->ft_table = otable;
1723 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next);
1726 * The map does not have the same possibility of threads still
1727 * holding references to it. So always free it as long as it
1728 * does not reference the original static allocation.
1730 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE))
1731 free(omap, M_FILEDESC);
1735 * Allocate a file descriptor for the process.
1738 fdalloc(struct thread *td, int minfd, int *result)
1740 struct proc *p = td->td_proc;
1741 struct filedesc *fdp = p->p_fd;
1742 int fd, maxfd, allocfd;
1747 FILEDESC_XLOCK_ASSERT(fdp);
1749 if (fdp->fd_freefile > minfd)
1750 minfd = fdp->fd_freefile;
1752 maxfd = getmaxfd(td);
1755 * Search the bitmap for a free descriptor starting at minfd.
1756 * If none is found, grow the file table.
1758 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles);
1761 if (fd >= fdp->fd_nfiles) {
1762 allocfd = min(fd * 2, maxfd);
1766 error = racct_set(p, RACCT_NOFILE, allocfd);
1773 * fd is already equal to first free descriptor >= minfd, so
1774 * we only need to grow the table and we are done.
1776 fdgrowtable_exp(fdp, allocfd);
1780 * Perform some sanity checks, then mark the file descriptor as
1781 * used and return it to the caller.
1783 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles),
1784 ("invalid descriptor %d", fd));
1785 KASSERT(!fdisused(fdp, fd),
1786 ("fd_first_free() returned non-free descriptor"));
1787 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL,
1788 ("file descriptor isn't free"));
1795 * Allocate n file descriptors for the process.
1798 fdallocn(struct thread *td, int minfd, int *fds, int n)
1800 struct proc *p = td->td_proc;
1801 struct filedesc *fdp = p->p_fd;
1804 FILEDESC_XLOCK_ASSERT(fdp);
1806 for (i = 0; i < n; i++)
1807 if (fdalloc(td, 0, &fds[i]) != 0)
1811 for (i--; i >= 0; i--)
1812 fdunused(fdp, fds[i]);
1820 * Create a new open file structure and allocate a file descriptor for the
1821 * process that refers to it. We add one reference to the file for the
1822 * descriptor table and one reference for resultfp. This is to prevent us
1823 * being preempted and the entry in the descriptor table closed after we
1824 * release the FILEDESC lock.
1827 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags,
1828 struct filecaps *fcaps)
1833 error = falloc_noinstall(td, &fp);
1835 return (error); /* no reference held on error */
1837 error = finstall(td, fp, &fd, flags, fcaps);
1839 fdrop(fp, td); /* one reference (fp only) */
1843 if (resultfp != NULL)
1844 *resultfp = fp; /* copy out result */
1846 fdrop(fp, td); /* release local reference */
1848 if (resultfd != NULL)
1855 * Create a new open file structure without allocating a file descriptor.
1858 falloc_noinstall(struct thread *td, struct file **resultfp)
1861 int maxuserfiles = maxfiles - (maxfiles / 20);
1863 static struct timeval lastfail;
1866 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__));
1868 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1;
1869 if ((openfiles_new >= maxuserfiles &&
1870 priv_check(td, PRIV_MAXFILES) != 0) ||
1871 openfiles_new >= maxfiles) {
1872 atomic_subtract_int(&openfiles, 1);
1873 if (ppsratecheck(&lastfail, &curfail, 1)) {
1874 printf("kern.maxfiles limit exceeded by uid %i, (%s) "
1875 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm);
1879 fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO);
1880 refcount_init(&fp->f_count, 1);
1881 fp->f_cred = crhold(td->td_ucred);
1882 fp->f_ops = &badfileops;
1888 * Install a file in a file descriptor table.
1891 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags,
1892 struct filecaps *fcaps)
1894 struct filedescent *fde;
1898 filecaps_validate(fcaps, __func__);
1899 FILEDESC_XLOCK_ASSERT(fdp);
1901 fde = &fdp->fd_ofiles[fd];
1903 seq_write_begin(&fde->fde_seq);
1906 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0;
1908 filecaps_move(fcaps, &fde->fde_caps);
1910 filecaps_fill(&fde->fde_caps);
1912 seq_write_end(&fde->fde_seq);
1917 finstall(struct thread *td, struct file *fp, int *fd, int flags,
1918 struct filecaps *fcaps)
1920 struct filedesc *fdp = td->td_proc->p_fd;
1925 FILEDESC_XLOCK(fdp);
1926 if ((error = fdalloc(td, 0, fd))) {
1927 FILEDESC_XUNLOCK(fdp);
1931 _finstall(fdp, fp, *fd, flags, fcaps);
1932 FILEDESC_XUNLOCK(fdp);
1937 * Build a new filedesc structure from another.
1938 * Copy the current, root, and jail root vnode references.
1940 * If fdp is not NULL, return with it shared locked.
1943 fdinit(struct filedesc *fdp, bool prepfiles)
1945 struct filedesc0 *newfdp0;
1946 struct filedesc *newfdp;
1948 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO);
1949 newfdp = &newfdp0->fd_fd;
1951 /* Create the file descriptor table. */
1952 FILEDESC_LOCK_INIT(newfdp);
1953 refcount_init(&newfdp->fd_refcnt, 1);
1954 refcount_init(&newfdp->fd_holdcnt, 1);
1955 newfdp->fd_cmask = CMASK;
1956 newfdp->fd_map = newfdp0->fd_dmap;
1957 newfdp->fd_lastfile = -1;
1958 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles;
1959 newfdp->fd_files->fdt_nfiles = NDFILE;
1964 if (prepfiles && fdp->fd_lastfile >= newfdp->fd_nfiles)
1965 fdgrowtable(newfdp, fdp->fd_lastfile + 1);
1967 FILEDESC_SLOCK(fdp);
1968 newfdp->fd_cdir = fdp->fd_cdir;
1969 if (newfdp->fd_cdir)
1970 vrefact(newfdp->fd_cdir);
1971 newfdp->fd_rdir = fdp->fd_rdir;
1972 if (newfdp->fd_rdir)
1973 vrefact(newfdp->fd_rdir);
1974 newfdp->fd_jdir = fdp->fd_jdir;
1975 if (newfdp->fd_jdir)
1976 vrefact(newfdp->fd_jdir);
1979 FILEDESC_SUNLOCK(fdp);
1981 while (fdp->fd_lastfile >= newfdp->fd_nfiles) {
1982 FILEDESC_SUNLOCK(fdp);
1983 fdgrowtable(newfdp, fdp->fd_lastfile + 1);
1984 FILEDESC_SLOCK(fdp);
1991 static struct filedesc *
1992 fdhold(struct proc *p)
1994 struct filedesc *fdp;
1996 PROC_LOCK_ASSERT(p, MA_OWNED);
1999 refcount_acquire(&fdp->fd_holdcnt);
2004 fddrop(struct filedesc *fdp)
2007 if (fdp->fd_holdcnt > 1) {
2008 if (refcount_release(&fdp->fd_holdcnt) == 0)
2012 FILEDESC_LOCK_DESTROY(fdp);
2013 uma_zfree(filedesc0_zone, fdp);
2017 * Share a filedesc structure.
2020 fdshare(struct filedesc *fdp)
2023 refcount_acquire(&fdp->fd_refcnt);
2028 * Unshare a filedesc structure, if necessary by making a copy
2031 fdunshare(struct thread *td)
2033 struct filedesc *tmp;
2034 struct proc *p = td->td_proc;
2036 if (p->p_fd->fd_refcnt == 1)
2039 tmp = fdcopy(p->p_fd);
2045 fdinstall_remapped(struct thread *td, struct filedesc *fdp)
2049 td->td_proc->p_fd = fdp;
2053 * Copy a filedesc structure. A NULL pointer in returns a NULL reference,
2054 * this is to ease callers, not catch errors.
2057 fdcopy(struct filedesc *fdp)
2059 struct filedesc *newfdp;
2060 struct filedescent *nfde, *ofde;
2065 newfdp = fdinit(fdp, true);
2066 /* copy all passable descriptors (i.e. not kqueue) */
2067 newfdp->fd_freefile = -1;
2068 for (i = 0; i <= fdp->fd_lastfile; ++i) {
2069 ofde = &fdp->fd_ofiles[i];
2070 if (ofde->fde_file == NULL ||
2071 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) {
2072 if (newfdp->fd_freefile == -1)
2073 newfdp->fd_freefile = i;
2076 nfde = &newfdp->fd_ofiles[i];
2078 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true);
2079 fhold(nfde->fde_file);
2080 fdused_init(newfdp, i);
2081 newfdp->fd_lastfile = i;
2083 if (newfdp->fd_freefile == -1)
2084 newfdp->fd_freefile = i;
2085 newfdp->fd_cmask = fdp->fd_cmask;
2086 FILEDESC_SUNLOCK(fdp);
2091 * Copies a filedesc structure, while remapping all file descriptors
2092 * stored inside using a translation table.
2094 * File descriptors are copied over to the new file descriptor table,
2095 * regardless of whether the close-on-exec flag is set.
2098 fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds,
2099 struct filedesc **ret)
2101 struct filedesc *newfdp;
2102 struct filedescent *nfde, *ofde;
2107 newfdp = fdinit(fdp, true);
2108 if (nfds > fdp->fd_lastfile + 1) {
2109 /* New table cannot be larger than the old one. */
2113 /* Copy all passable descriptors (i.e. not kqueue). */
2114 newfdp->fd_freefile = nfds;
2115 for (i = 0; i < nfds; ++i) {
2116 if (fds[i] < 0 || fds[i] > fdp->fd_lastfile) {
2117 /* File descriptor out of bounds. */
2121 ofde = &fdp->fd_ofiles[fds[i]];
2122 if (ofde->fde_file == NULL) {
2123 /* Unused file descriptor. */
2127 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) {
2128 /* File descriptor cannot be passed. */
2132 nfde = &newfdp->fd_ofiles[i];
2134 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true);
2135 fhold(nfde->fde_file);
2136 fdused_init(newfdp, i);
2137 newfdp->fd_lastfile = i;
2139 newfdp->fd_cmask = fdp->fd_cmask;
2140 FILEDESC_SUNLOCK(fdp);
2144 FILEDESC_SUNLOCK(fdp);
2145 fdescfree_remapped(newfdp);
2150 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e.
2151 * one of processes using it exits) and the table used to be shared.
2154 fdclearlocks(struct thread *td)
2156 struct filedesc *fdp;
2157 struct filedesc_to_leader *fdtol;
2167 MPASS(fdtol != NULL);
2169 FILEDESC_XLOCK(fdp);
2170 KASSERT(fdtol->fdl_refcount > 0,
2171 ("filedesc_to_refcount botch: fdl_refcount=%d",
2172 fdtol->fdl_refcount));
2173 if (fdtol->fdl_refcount == 1 &&
2174 (p->p_leader->p_flag & P_ADVLOCK) != 0) {
2175 for (i = 0; i <= fdp->fd_lastfile; i++) {
2176 fp = fdp->fd_ofiles[i].fde_file;
2177 if (fp == NULL || fp->f_type != DTYPE_VNODE)
2180 FILEDESC_XUNLOCK(fdp);
2181 lf.l_whence = SEEK_SET;
2184 lf.l_type = F_UNLCK;
2186 (void) VOP_ADVLOCK(vp,
2187 (caddr_t)p->p_leader, F_UNLCK,
2189 FILEDESC_XLOCK(fdp);
2194 if (fdtol->fdl_refcount == 1) {
2195 if (fdp->fd_holdleaderscount > 0 &&
2196 (p->p_leader->p_flag & P_ADVLOCK) != 0) {
2198 * close() or kern_dup() has cleared a reference
2199 * in a shared file descriptor table.
2201 fdp->fd_holdleaderswakeup = 1;
2202 sx_sleep(&fdp->fd_holdleaderscount,
2203 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0);
2206 if (fdtol->fdl_holdcount > 0) {
2208 * Ensure that fdtol->fdl_leader remains
2209 * valid in closef().
2211 fdtol->fdl_wakeup = 1;
2212 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK,
2217 fdtol->fdl_refcount--;
2218 if (fdtol->fdl_refcount == 0 &&
2219 fdtol->fdl_holdcount == 0) {
2220 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev;
2221 fdtol->fdl_prev->fdl_next = fdtol->fdl_next;
2225 FILEDESC_XUNLOCK(fdp);
2227 free(fdtol, M_FILEDESC_TO_LEADER);
2231 * Release a filedesc structure.
2234 fdescfree_fds(struct thread *td, struct filedesc *fdp, bool needclose)
2236 struct filedesc0 *fdp0;
2237 struct freetable *ft, *tft;
2238 struct filedescent *fde;
2242 for (i = 0; i <= fdp->fd_lastfile; i++) {
2243 fde = &fdp->fd_ofiles[i];
2248 (void) closef(fp, td);
2254 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE))
2255 free(fdp->fd_map, M_FILEDESC);
2256 if (fdp->fd_nfiles > NDFILE)
2257 free(fdp->fd_files, M_FILEDESC);
2259 fdp0 = (struct filedesc0 *)fdp;
2260 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft)
2261 free(ft->ft_table, M_FILEDESC);
2267 fdescfree(struct thread *td)
2270 struct filedesc *fdp;
2271 struct vnode *cdir, *jdir, *rdir;
2280 racct_set(p, RACCT_NOFILE, 0);
2285 if (p->p_fdtol != NULL)
2292 if (refcount_release(&fdp->fd_refcnt) == 0)
2295 FILEDESC_XLOCK(fdp);
2296 cdir = fdp->fd_cdir;
2297 fdp->fd_cdir = NULL;
2298 rdir = fdp->fd_rdir;
2299 fdp->fd_rdir = NULL;
2300 jdir = fdp->fd_jdir;
2301 fdp->fd_jdir = NULL;
2302 FILEDESC_XUNLOCK(fdp);
2311 fdescfree_fds(td, fdp, 1);
2315 fdescfree_remapped(struct filedesc *fdp)
2318 if (fdp->fd_cdir != NULL)
2319 vrele(fdp->fd_cdir);
2320 if (fdp->fd_rdir != NULL)
2321 vrele(fdp->fd_rdir);
2322 if (fdp->fd_jdir != NULL)
2323 vrele(fdp->fd_jdir);
2325 fdescfree_fds(curthread, fdp, 0);
2329 * For setugid programs, we don't want to people to use that setugidness
2330 * to generate error messages which write to a file which otherwise would
2331 * otherwise be off-limits to the process. We check for filesystems where
2332 * the vnode can change out from under us after execve (like [lin]procfs).
2334 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is
2335 * sufficient. We also don't check for setugidness since we know we are.
2338 is_unsafe(struct file *fp)
2342 if (fp->f_type != DTYPE_VNODE)
2346 return ((vp->v_vflag & VV_PROCDEP) != 0);
2350 * Make this setguid thing safe, if at all possible.
2353 fdsetugidsafety(struct thread *td)
2355 struct filedesc *fdp;
2359 fdp = td->td_proc->p_fd;
2360 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2361 MPASS(fdp->fd_nfiles >= 3);
2362 for (i = 0; i <= 2; i++) {
2363 fp = fdp->fd_ofiles[i].fde_file;
2364 if (fp != NULL && is_unsafe(fp)) {
2365 FILEDESC_XLOCK(fdp);
2366 knote_fdclose(td, i);
2368 * NULL-out descriptor prior to close to avoid
2369 * a race while close blocks.
2372 FILEDESC_XUNLOCK(fdp);
2373 (void) closef(fp, td);
2379 * If a specific file object occupies a specific file descriptor, close the
2380 * file descriptor entry and drop a reference on the file object. This is a
2381 * convenience function to handle a subsequent error in a function that calls
2382 * falloc() that handles the race that another thread might have closed the
2383 * file descriptor out from under the thread creating the file object.
2386 fdclose(struct thread *td, struct file *fp, int idx)
2388 struct filedesc *fdp = td->td_proc->p_fd;
2390 FILEDESC_XLOCK(fdp);
2391 if (fdp->fd_ofiles[idx].fde_file == fp) {
2393 FILEDESC_XUNLOCK(fdp);
2396 FILEDESC_XUNLOCK(fdp);
2400 * Close any files on exec?
2403 fdcloseexec(struct thread *td)
2405 struct filedesc *fdp;
2406 struct filedescent *fde;
2410 fdp = td->td_proc->p_fd;
2411 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2412 for (i = 0; i <= fdp->fd_lastfile; i++) {
2413 fde = &fdp->fd_ofiles[i];
2415 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE ||
2416 (fde->fde_flags & UF_EXCLOSE))) {
2417 FILEDESC_XLOCK(fdp);
2419 (void) closefp(fdp, i, fp, td, 0);
2420 FILEDESC_UNLOCK_ASSERT(fdp);
2426 * It is unsafe for set[ug]id processes to be started with file
2427 * descriptors 0..2 closed, as these descriptors are given implicit
2428 * significance in the Standard C library. fdcheckstd() will create a
2429 * descriptor referencing /dev/null for each of stdin, stdout, and
2430 * stderr that is not already open.
2433 fdcheckstd(struct thread *td)
2435 struct filedesc *fdp;
2437 int i, error, devnull;
2439 fdp = td->td_proc->p_fd;
2440 KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared"));
2441 MPASS(fdp->fd_nfiles >= 3);
2443 for (i = 0; i <= 2; i++) {
2444 if (fdp->fd_ofiles[i].fde_file != NULL)
2447 save = td->td_retval[0];
2448 if (devnull != -1) {
2449 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i);
2451 error = kern_openat(td, AT_FDCWD, "/dev/null",
2452 UIO_SYSSPACE, O_RDWR, 0);
2454 devnull = td->td_retval[0];
2455 KASSERT(devnull == i, ("we didn't get our fd"));
2458 td->td_retval[0] = save;
2466 * Internal form of close. Decrement reference count on file structure.
2467 * Note: td may be NULL when closing a file that was being passed in a
2470 * XXXRW: Giant is not required for the caller, but often will be held; this
2471 * makes it moderately likely the Giant will be recursed in the VFS case.
2474 closef(struct file *fp, struct thread *td)
2478 struct filedesc_to_leader *fdtol;
2479 struct filedesc *fdp;
2482 * POSIX record locking dictates that any close releases ALL
2483 * locks owned by this process. This is handled by setting
2484 * a flag in the unlock to free ONLY locks obeying POSIX
2485 * semantics, and not to free BSD-style file locks.
2486 * If the descriptor was in a message, POSIX-style locks
2487 * aren't passed with the descriptor, and the thread pointer
2488 * will be NULL. Callers should be careful only to pass a
2489 * NULL thread pointer when there really is no owning
2490 * context that might have locks, or the locks will be
2493 if (fp->f_type == DTYPE_VNODE && td != NULL) {
2495 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
2496 lf.l_whence = SEEK_SET;
2499 lf.l_type = F_UNLCK;
2500 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader,
2501 F_UNLCK, &lf, F_POSIX);
2503 fdtol = td->td_proc->p_fdtol;
2504 if (fdtol != NULL) {
2506 * Handle special case where file descriptor table is
2507 * shared between multiple process leaders.
2509 fdp = td->td_proc->p_fd;
2510 FILEDESC_XLOCK(fdp);
2511 for (fdtol = fdtol->fdl_next;
2512 fdtol != td->td_proc->p_fdtol;
2513 fdtol = fdtol->fdl_next) {
2514 if ((fdtol->fdl_leader->p_flag &
2517 fdtol->fdl_holdcount++;
2518 FILEDESC_XUNLOCK(fdp);
2519 lf.l_whence = SEEK_SET;
2522 lf.l_type = F_UNLCK;
2524 (void) VOP_ADVLOCK(vp,
2525 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf,
2527 FILEDESC_XLOCK(fdp);
2528 fdtol->fdl_holdcount--;
2529 if (fdtol->fdl_holdcount == 0 &&
2530 fdtol->fdl_wakeup != 0) {
2531 fdtol->fdl_wakeup = 0;
2535 FILEDESC_XUNLOCK(fdp);
2538 return (fdrop(fp, td));
2542 * Initialize the file pointer with the specified properties.
2544 * The ops are set with release semantics to be certain that the flags, type,
2545 * and data are visible when ops is. This is to prevent ops methods from being
2546 * called with bad data.
2549 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops)
2554 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops);
2558 fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
2559 struct file **fpp, struct filecaps *havecapsp)
2561 struct filedescent *fde;
2564 FILEDESC_LOCK_ASSERT(fdp);
2566 fde = fdeget_locked(fdp, fd);
2573 error = cap_check(cap_rights_fde(fde), needrightsp);
2578 if (havecapsp != NULL)
2579 filecaps_copy(&fde->fde_caps, havecapsp, true);
2581 *fpp = fde->fde_file;
2589 fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp,
2590 struct file **fpp, struct filecaps *havecapsp)
2592 struct filedesc *fdp = td->td_proc->p_fd;
2594 #ifndef CAPABILITIES
2595 error = fget_unlocked(fdp, fd, needrightsp, fpp, NULL);
2596 if (error == 0 && havecapsp != NULL)
2597 filecaps_fill(havecapsp);
2603 error = fget_unlocked(fdp, fd, needrightsp, &fp, &seq);
2607 if (havecapsp != NULL) {
2608 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps,
2609 havecapsp, false)) {
2615 if (!fd_modified(fdp, fd, seq))
2624 FILEDESC_SLOCK(fdp);
2625 error = fget_cap_locked(fdp, fd, needrightsp, fpp, havecapsp);
2628 FILEDESC_SUNLOCK(fdp);
2634 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
2635 struct file **fpp, seq_t *seqp)
2638 struct filedescent *fde;
2640 struct fdescenttbl *fdt;
2645 cap_rights_t haverights;
2649 fdt = fdp->fd_files;
2650 if ((u_int)fd >= fdt->fdt_nfiles)
2653 * Fetch the descriptor locklessly. We avoid fdrop() races by
2654 * never raising a refcount above 0. To accomplish this we have
2655 * to use a cmpset loop rather than an atomic_add. The descriptor
2656 * must be re-verified once we acquire a reference to be certain
2657 * that the identity is still correct and we did not lose a race
2658 * due to preemption.
2662 seq = seq_read(fd_seq(fdt, fd));
2663 fde = &fdt->fdt_ofiles[fd];
2664 haverights = *cap_rights_fde(fde);
2666 if (!seq_consistent(fd_seq(fdt, fd), seq))
2669 fp = fdt->fdt_ofiles[fd].fde_file;
2674 error = cap_check(&haverights, needrightsp);
2678 count = fp->f_count;
2682 * Force a reload. Other thread could reallocate the
2683 * table before this fd was closed, so it possible that
2684 * there is a stale fp pointer in cached version.
2686 fdt = *(struct fdescenttbl * volatile *)&(fdp->fd_files);
2690 * Use an acquire barrier to force re-reading of fdt so it is
2691 * refreshed for verification.
2693 if (atomic_fcmpset_acq_int(&fp->f_count, &count, count + 1) == 0)
2695 fdt = fdp->fd_files;
2697 if (seq_consistent_nomb(fd_seq(fdt, fd), seq))
2699 if (fp == fdt->fdt_ofiles[fd].fde_file)
2702 fdrop(fp, curthread);
2714 * Extract the file pointer associated with the specified descriptor for the
2715 * current user process.
2717 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is
2720 * File's rights will be checked against the capability rights mask.
2722 * If an error occurred the non-zero error is returned and *fpp is set to
2723 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is
2724 * responsible for fdrop().
2727 _fget(struct thread *td, int fd, struct file **fpp, int flags,
2728 cap_rights_t *needrightsp, seq_t *seqp)
2730 struct filedesc *fdp;
2735 fdp = td->td_proc->p_fd;
2736 error = fget_unlocked(fdp, fd, needrightsp, &fp, seqp);
2739 if (fp->f_ops == &badfileops) {
2745 * FREAD and FWRITE failure return EBADF as per POSIX.
2751 if ((fp->f_flag & flags) == 0)
2755 if ((fp->f_flag & (FREAD | FEXEC)) == 0 ||
2756 ((fp->f_flag & FWRITE) != 0))
2762 KASSERT(0, ("wrong flags"));
2775 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
2778 return (_fget(td, fd, fpp, 0, rightsp, NULL));
2782 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, u_char *maxprotp,
2786 #ifndef CAPABILITIES
2787 error = _fget(td, fd, fpp, 0, rightsp, NULL);
2788 if (maxprotp != NULL)
2789 *maxprotp = VM_PROT_ALL;
2791 struct filedesc *fdp = td->td_proc->p_fd;
2794 MPASS(cap_rights_is_set(rightsp, CAP_MMAP));
2796 error = _fget(td, fd, fpp, 0, rightsp, &seq);
2800 * If requested, convert capability rights to access flags.
2802 if (maxprotp != NULL)
2803 *maxprotp = cap_rights_to_vmprot(cap_rights(fdp, fd));
2804 if (!fd_modified(fdp, fd, seq))
2813 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
2816 return (_fget(td, fd, fpp, FREAD, rightsp, NULL));
2820 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
2823 return (_fget(td, fd, fpp, FWRITE, rightsp, NULL));
2827 fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp, int needfcntl,
2830 struct filedesc *fdp = td->td_proc->p_fd;
2831 #ifndef CAPABILITIES
2832 return (fget_unlocked(fdp, fd, rightsp, fpp, NULL));
2837 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL));
2839 error = fget_unlocked(fdp, fd, rightsp, fpp, &seq);
2842 error = cap_fcntl_check(fdp, fd, needfcntl);
2843 if (!fd_modified(fdp, fd, seq))
2856 * Like fget() but loads the underlying vnode, or returns an error if the
2857 * descriptor does not represent a vnode. Note that pipes use vnodes but
2858 * never have VM objects. The returned vnode will be vref()'d.
2860 * XXX: what about the unused flags ?
2863 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp,
2870 error = _fget(td, fd, &fp, flags, needrightsp, NULL);
2873 if (fp->f_vnode == NULL) {
2885 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2888 return (_fgetvp(td, fd, 0, rightsp, vpp));
2892 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp,
2893 struct filecaps *havecaps, struct vnode **vpp)
2895 struct filedesc *fdp;
2896 struct filecaps caps;
2900 fdp = td->td_proc->p_fd;
2901 error = fget_cap_locked(fdp, fd, needrightsp, &fp, &caps);
2904 if (fp->f_ops == &badfileops) {
2908 if (fp->f_vnode == NULL) {
2919 filecaps_free(&caps);
2924 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2927 return (_fgetvp(td, fd, FREAD, rightsp, vpp));
2931 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
2934 return (_fgetvp(td, fd, FEXEC, rightsp, vpp));
2939 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp,
2943 return (_fgetvp(td, fd, FWRITE, rightsp, vpp));
2948 * Handle the last reference to a file being closed.
2951 _fdrop(struct file *fp, struct thread *td)
2955 if (fp->f_count != 0)
2956 panic("fdrop: count %d", fp->f_count);
2957 error = fo_close(fp, td);
2958 atomic_subtract_int(&openfiles, 1);
2960 free(fp->f_advice, M_FADVISE);
2961 uma_zfree(file_zone, fp);
2967 * Apply an advisory lock on a file descriptor.
2969 * Just attempt to get a record lock of the requested type on the entire file
2970 * (l_whence = SEEK_SET, l_start = 0, l_len = 0).
2972 #ifndef _SYS_SYSPROTO_H_
2980 sys_flock(struct thread *td, struct flock_args *uap)
2985 cap_rights_t rights;
2988 error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FLOCK), &fp);
2991 if (fp->f_type != DTYPE_VNODE) {
2993 return (EOPNOTSUPP);
2997 lf.l_whence = SEEK_SET;
3000 if (uap->how & LOCK_UN) {
3001 lf.l_type = F_UNLCK;
3002 atomic_clear_int(&fp->f_flag, FHASLOCK);
3003 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK);
3006 if (uap->how & LOCK_EX)
3007 lf.l_type = F_WRLCK;
3008 else if (uap->how & LOCK_SH)
3009 lf.l_type = F_RDLCK;
3014 atomic_set_int(&fp->f_flag, FHASLOCK);
3015 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
3016 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT);
3022 * Duplicate the specified descriptor to a free descriptor.
3025 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode,
3026 int openerror, int *indxp)
3028 struct filedescent *newfde, *oldfde;
3033 KASSERT(openerror == ENODEV || openerror == ENXIO,
3034 ("unexpected error %d in %s", openerror, __func__));
3037 * If the to-be-dup'd fd number is greater than the allowed number
3038 * of file descriptors, or the fd to be dup'd has already been
3039 * closed, then reject.
3041 FILEDESC_XLOCK(fdp);
3042 if ((fp = fget_locked(fdp, dfd)) == NULL) {
3043 FILEDESC_XUNLOCK(fdp);
3047 error = fdalloc(td, 0, &indx);
3049 FILEDESC_XUNLOCK(fdp);
3054 * There are two cases of interest here.
3056 * For ENODEV simply dup (dfd) to file descriptor (indx) and return.
3058 * For ENXIO steal away the file structure from (dfd) and store it in
3059 * (indx). (dfd) is effectively closed by this operation.
3061 switch (openerror) {
3064 * Check that the mode the file is being opened for is a
3065 * subset of the mode of the existing descriptor.
3067 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) {
3068 fdunused(fdp, indx);
3069 FILEDESC_XUNLOCK(fdp);
3073 newfde = &fdp->fd_ofiles[indx];
3074 oldfde = &fdp->fd_ofiles[dfd];
3075 ioctls = filecaps_copy_prep(&oldfde->fde_caps);
3077 seq_write_begin(&newfde->fde_seq);
3079 memcpy(newfde, oldfde, fde_change_size);
3080 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps,
3083 seq_write_end(&newfde->fde_seq);
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 seq_write_begin(&newfde->fde_seq);
3095 memcpy(newfde, oldfde, fde_change_size);
3096 oldfde->fde_file = NULL;
3099 seq_write_end(&newfde->fde_seq);
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)
3378 xf.xf_data = fp->f_data;
3379 xf.xf_vnode = fp->f_vnode;
3380 xf.xf_type = 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 cap_rights_init(&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);