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
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
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20 * 3. Neither the name of the University nor the names of its contributors
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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>
67 #include <sys/protosw.h>
68 #include <sys/racct.h>
69 #include <sys/resourcevar.h>
71 #include <sys/signalvar.h>
76 #include <sys/syscallsubr.h>
77 #include <sys/sysctl.h>
78 #include <sys/sysproto.h>
79 #include <sys/unistd.h>
81 #include <sys/vnode.h>
82 #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_PWD, "pwd", "Descriptor table vnodes");
95 static MALLOC_DEFINE(M_PWDDESC, "pwddesc", "Pwd descriptors");
96 static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader",
97 "file desc to leader structures");
98 static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures");
99 MALLOC_DEFINE(M_FILECAPS, "filecaps", "descriptor capabilities");
101 MALLOC_DECLARE(M_FADVISE);
103 static __read_mostly uma_zone_t file_zone;
104 static __read_mostly uma_zone_t filedesc0_zone;
105 __read_mostly uma_zone_t pwd_zone;
108 static int closefp(struct filedesc *fdp, int fd, struct file *fp,
109 struct thread *td, bool holdleaders, bool audit);
110 static void export_file_to_kinfo(struct file *fp, int fd,
111 cap_rights_t *rightsp, struct kinfo_file *kif,
112 struct filedesc *fdp, int flags);
113 static int fd_first_free(struct filedesc *fdp, int low, int size);
114 static void fdgrowtable(struct filedesc *fdp, int nfd);
115 static void fdgrowtable_exp(struct filedesc *fdp, int nfd);
116 static void fdunused(struct filedesc *fdp, int fd);
117 static void fdused(struct filedesc *fdp, int fd);
118 static int fget_unlocked_seq(struct filedesc *fdp, int fd,
119 cap_rights_t *needrightsp, struct file **fpp, seqc_t *seqp);
120 static int getmaxfd(struct thread *td);
121 static u_long *filecaps_copy_prep(const struct filecaps *src);
122 static void filecaps_copy_finish(const struct filecaps *src,
123 struct filecaps *dst, u_long *ioctls);
124 static u_long *filecaps_free_prep(struct filecaps *fcaps);
125 static void filecaps_free_finish(u_long *ioctls);
127 static struct pwd *pwd_alloc(void);
132 * - An array of open file descriptors (fd_ofiles)
133 * - An array of file flags (fd_ofileflags)
134 * - A bitmap recording which descriptors are in use (fd_map)
136 * A process starts out with NDFILE descriptors. The value of NDFILE has
137 * been selected based the historical limit of 20 open files, and an
138 * assumption that the majority of processes, especially short-lived
139 * processes like shells, will never need more.
141 * If this initial allocation is exhausted, a larger descriptor table and
142 * map are allocated dynamically, and the pointers in the process's struct
143 * filedesc are updated to point to those. This is repeated every time
144 * the process runs out of file descriptors (provided it hasn't hit its
147 * Since threads may hold references to individual descriptor table
148 * entries, the tables are never freed. Instead, they are placed on a
149 * linked list and freed only when the struct filedesc is released.
152 #define NDSLOTSIZE sizeof(NDSLOTTYPE)
153 #define NDENTRIES (NDSLOTSIZE * __CHAR_BIT)
154 #define NDSLOT(x) ((x) / NDENTRIES)
155 #define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES))
156 #define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES)
159 * SLIST entry used to keep track of ofiles which must be reclaimed when
163 struct fdescenttbl *ft_table;
164 SLIST_ENTRY(freetable) ft_next;
168 * Initial allocation: a filedesc structure + the head of SLIST used to
169 * keep track of old ofiles + enough space for NDFILE descriptors.
172 struct fdescenttbl0 {
174 struct filedescent fdt_ofiles[NDFILE];
178 struct filedesc fd_fd;
179 SLIST_HEAD(, freetable) fd_free;
180 struct fdescenttbl0 fd_dfiles;
181 NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)];
185 * Descriptor management.
187 static int __exclusive_cache_line openfiles; /* actual number of open files */
188 struct mtx sigio_lock; /* mtx to protect pointers to sigio */
189 void __read_mostly (*mq_fdclose)(struct thread *td, int fd, struct file *fp);
192 * If low >= size, just return low. Otherwise find the first zero bit in the
193 * given bitmap, starting at low and not exceeding size - 1. Return size if
197 fd_first_free(struct filedesc *fdp, int low, int size)
199 NDSLOTTYPE *map = fdp->fd_map;
207 if (low % NDENTRIES) {
208 mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES)));
209 if ((mask &= ~map[off]) != 0UL)
210 return (off * NDENTRIES + ffsl(mask) - 1);
213 for (maxoff = NDSLOTS(size); off < maxoff; ++off)
214 if (map[off] != ~0UL)
215 return (off * NDENTRIES + ffsl(~map[off]) - 1);
220 * Find the last used fd.
222 * Call this variant if fdp can't be modified by anyone else (e.g, during exec).
223 * Otherwise use fdlastfile.
226 fdlastfile_single(struct filedesc *fdp)
228 NDSLOTTYPE *map = fdp->fd_map;
231 off = NDSLOT(fdp->fd_nfiles - 1);
232 for (minoff = NDSLOT(0); off >= minoff; --off)
234 return (off * NDENTRIES + flsl(map[off]) - 1);
239 fdlastfile(struct filedesc *fdp)
242 FILEDESC_LOCK_ASSERT(fdp);
243 return (fdlastfile_single(fdp));
247 fdisused(struct filedesc *fdp, int fd)
250 KASSERT(fd >= 0 && fd < fdp->fd_nfiles,
251 ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles));
253 return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0);
257 * Mark a file descriptor as used.
260 fdused_init(struct filedesc *fdp, int fd)
263 KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd));
265 fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd);
269 fdused(struct filedesc *fdp, int fd)
272 FILEDESC_XLOCK_ASSERT(fdp);
274 fdused_init(fdp, fd);
275 if (fd == fdp->fd_freefile)
280 * Mark a file descriptor as unused.
283 fdunused(struct filedesc *fdp, int fd)
286 FILEDESC_XLOCK_ASSERT(fdp);
288 KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd));
289 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL,
290 ("fd=%d is still in use", fd));
292 fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd);
293 if (fd < fdp->fd_freefile)
294 fdp->fd_freefile = fd;
298 * Free a file descriptor.
300 * Avoid some work if fdp is about to be destroyed.
303 fdefree_last(struct filedescent *fde)
306 filecaps_free(&fde->fde_caps);
310 fdfree(struct filedesc *fdp, int fd)
312 struct filedescent *fde;
314 FILEDESC_XLOCK_ASSERT(fdp);
315 fde = &fdp->fd_ofiles[fd];
317 seqc_write_begin(&fde->fde_seqc);
319 fde->fde_file = NULL;
321 seqc_write_end(&fde->fde_seqc);
328 * System calls on descriptors.
330 #ifndef _SYS_SYSPROTO_H_
331 struct getdtablesize_args {
337 sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap)
343 td->td_retval[0] = getmaxfd(td);
345 PROC_LOCK(td->td_proc);
346 lim = racct_get_limit(td->td_proc, RACCT_NOFILE);
347 PROC_UNLOCK(td->td_proc);
348 if (lim < td->td_retval[0])
349 td->td_retval[0] = lim;
355 * Duplicate a file descriptor to a particular value.
357 * Note: keep in mind that a potential race condition exists when closing
358 * descriptors from a shared descriptor table (via rfork).
360 #ifndef _SYS_SYSPROTO_H_
368 sys_dup2(struct thread *td, struct dup2_args *uap)
371 return (kern_dup(td, FDDUP_FIXED, 0, (int)uap->from, (int)uap->to));
375 * Duplicate a file descriptor.
377 #ifndef _SYS_SYSPROTO_H_
384 sys_dup(struct thread *td, struct dup_args *uap)
387 return (kern_dup(td, FDDUP_NORMAL, 0, (int)uap->fd, 0));
391 * The file control system call.
393 #ifndef _SYS_SYSPROTO_H_
402 sys_fcntl(struct thread *td, struct fcntl_args *uap)
405 return (kern_fcntl_freebsd(td, uap->fd, uap->cmd, uap->arg));
409 kern_fcntl_freebsd(struct thread *td, int fd, int cmd, long arg)
423 * Convert old flock structure to new.
425 error = copyin((void *)(intptr_t)arg, &ofl, sizeof(ofl));
426 fl.l_start = ofl.l_start;
427 fl.l_len = ofl.l_len;
428 fl.l_pid = ofl.l_pid;
429 fl.l_type = ofl.l_type;
430 fl.l_whence = ofl.l_whence;
444 arg1 = (intptr_t)&fl;
450 error = copyin((void *)(intptr_t)arg, &fl, sizeof(fl));
451 arg1 = (intptr_t)&fl;
459 error = kern_fcntl(td, fd, newcmd, arg1);
462 if (cmd == F_OGETLK) {
463 ofl.l_start = fl.l_start;
464 ofl.l_len = fl.l_len;
465 ofl.l_pid = fl.l_pid;
466 ofl.l_type = fl.l_type;
467 ofl.l_whence = fl.l_whence;
468 error = copyout(&ofl, (void *)(intptr_t)arg, sizeof(ofl));
469 } else if (cmd == F_GETLK) {
470 error = copyout(&fl, (void *)(intptr_t)arg, sizeof(fl));
476 kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg)
478 struct filedesc *fdp;
480 struct file *fp, *fp2;
481 struct filedescent *fde;
485 struct kinfo_file *kif;
486 int error, flg, kif_sz, seals, tmp;
500 error = kern_dup(td, FDDUP_FCNTL, 0, fd, tmp);
503 case F_DUPFD_CLOEXEC:
505 error = kern_dup(td, FDDUP_FCNTL, FDDUP_FLAG_CLOEXEC, fd, tmp);
510 error = kern_dup(td, FDDUP_FIXED, 0, fd, tmp);
513 case F_DUP2FD_CLOEXEC:
515 error = kern_dup(td, FDDUP_FIXED, FDDUP_FLAG_CLOEXEC, fd, tmp);
521 fde = fdeget_locked(fdp, fd);
524 (fde->fde_flags & UF_EXCLOSE) ? FD_CLOEXEC : 0;
527 FILEDESC_SUNLOCK(fdp);
533 fde = fdeget_locked(fdp, fd);
535 fde->fde_flags = (fde->fde_flags & ~UF_EXCLOSE) |
536 (arg & FD_CLOEXEC ? UF_EXCLOSE : 0);
539 FILEDESC_XUNLOCK(fdp);
543 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETFL, &fp);
546 td->td_retval[0] = OFLAGS(fp->f_flag);
551 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETFL, &fp);
554 if (fp->f_ops == &path_fileops) {
560 tmp = flg = fp->f_flag;
562 tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS;
563 } while (atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0);
564 tmp = fp->f_flag & FNONBLOCK;
565 error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
570 tmp = fp->f_flag & FASYNC;
571 error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td);
576 atomic_clear_int(&fp->f_flag, FNONBLOCK);
578 (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td);
583 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_GETOWN, &fp);
586 error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td);
588 td->td_retval[0] = tmp;
593 error = fget_fcntl(td, fd, &cap_fcntl_rights, F_SETOWN, &fp);
597 error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td);
602 error = priv_check(td, PRIV_NFS_LOCKD);
610 /* FALLTHROUGH F_SETLK */
614 flp = (struct flock *)arg;
615 if ((flg & F_REMOTE) != 0 && flp->l_sysid == 0) {
620 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp);
623 if (fp->f_type != DTYPE_VNODE || fp->f_ops == &path_fileops) {
629 if (flp->l_whence == SEEK_CUR) {
630 foffset = foffset_get(fp);
633 foffset > OFF_MAX - flp->l_start)) {
638 flp->l_start += foffset;
642 switch (flp->l_type) {
644 if ((fp->f_flag & FREAD) == 0) {
648 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) {
649 PROC_LOCK(p->p_leader);
650 p->p_leader->p_flag |= P_ADVLOCK;
651 PROC_UNLOCK(p->p_leader);
653 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
657 if ((fp->f_flag & FWRITE) == 0) {
661 if ((p->p_leader->p_flag & P_ADVLOCK) == 0) {
662 PROC_LOCK(p->p_leader);
663 p->p_leader->p_flag |= P_ADVLOCK;
664 PROC_UNLOCK(p->p_leader);
666 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK,
670 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK,
674 if (flg != F_REMOTE) {
678 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
679 F_UNLCKSYS, flp, flg);
685 if (error != 0 || flp->l_type == F_UNLCK ||
686 flp->l_type == F_UNLCKSYS) {
692 * Check for a race with close.
694 * The vnode is now advisory locked (or unlocked, but this case
695 * is not really important) as the caller requested.
696 * We had to drop the filedesc lock, so we need to recheck if
697 * the descriptor is still valid, because if it was closed
698 * in the meantime we need to remove advisory lock from the
699 * vnode - close on any descriptor leading to an advisory
700 * locked vnode, removes that lock.
701 * We will return 0 on purpose in that case, as the result of
702 * successful advisory lock might have been externally visible
703 * already. This is fine - effectively we pretend to the caller
704 * that the closing thread was a bit slower and that the
705 * advisory lock succeeded before the close.
707 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp2);
713 flp->l_whence = SEEK_SET;
716 flp->l_type = F_UNLCK;
717 (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader,
718 F_UNLCK, flp, F_POSIX);
725 error = fget_unlocked(fdp, fd, &cap_flock_rights, &fp);
728 if (fp->f_type != DTYPE_VNODE || fp->f_ops == &path_fileops) {
733 flp = (struct flock *)arg;
734 if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK &&
735 flp->l_type != F_UNLCK) {
740 if (flp->l_whence == SEEK_CUR) {
741 foffset = foffset_get(fp);
742 if ((flp->l_start > 0 &&
743 foffset > OFF_MAX - flp->l_start) ||
745 foffset < OFF_MIN - flp->l_start)) {
750 flp->l_start += foffset;
753 error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp,
759 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp);
762 error = fo_add_seals(fp, arg);
767 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp);
770 if (fo_get_seals(fp, &seals) == 0)
771 td->td_retval[0] = seals;
778 arg = arg ? 128 * 1024: 0;
781 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp);
784 if (fp->f_type != DTYPE_VNODE || fp->f_ops == &path_fileops) {
790 if (vp->v_type != VREG) {
797 * Exclusive lock synchronizes against f_seqcount reads and
798 * writes in sequential_heuristic().
800 error = vn_lock(vp, LK_EXCLUSIVE);
806 bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize;
807 arg = MIN(arg, INT_MAX - bsize + 1);
808 fp->f_seqcount[UIO_READ] = MIN(IO_SEQMAX,
809 (arg + bsize - 1) / bsize);
810 atomic_set_int(&fp->f_flag, FRDAHEAD);
812 atomic_clear_int(&fp->f_flag, FRDAHEAD);
820 * Check if the vnode is part of a union stack (either the
821 * "union" flag from mount(2) or unionfs).
823 * Prior to introduction of this op libc's readdir would call
824 * fstatfs(2), in effect unnecessarily copying kilobytes of
825 * data just to check fs name and a mount flag.
827 * Fixing the code to handle everything in the kernel instead
828 * is a non-trivial endeavor and has low priority, thus this
829 * horrible kludge facilitates the current behavior in a much
830 * cheaper manner until someone(tm) sorts this out.
832 error = fget_unlocked(fdp, fd, &cap_no_rights, &fp);
835 if (fp->f_type != DTYPE_VNODE) {
842 * Since we don't prevent dooming the vnode even non-null mp
843 * found can become immediately stale. This is tolerable since
844 * mount points are type-stable (providing safe memory access)
845 * and any vfs op on this vnode going forward will return an
846 * error (meaning return value in this case is meaningless).
848 mp = atomic_load_ptr(&vp->v_mount);
849 if (__predict_false(mp == NULL)) {
854 td->td_retval[0] = 0;
855 if (mp->mnt_kern_flag & MNTK_UNIONFS ||
856 mp->mnt_flag & MNT_UNION)
857 td->td_retval[0] = 1;
862 #ifdef CAPABILITY_MODE
863 if (IN_CAPABILITY_MODE(td)) {
868 error = copyin((void *)arg, &kif_sz, sizeof(kif_sz));
871 if (kif_sz != sizeof(*kif)) {
875 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK | M_ZERO);
877 error = fget_cap_locked(fdp, fd, &cap_fcntl_rights, &fp, NULL);
878 if (error == 0 && fhold(fp)) {
879 export_file_to_kinfo(fp, fd, NULL, kif, fdp, 0);
880 FILEDESC_SUNLOCK(fdp);
882 if ((kif->kf_status & KF_ATTR_VALID) != 0) {
883 kif->kf_structsize = sizeof(*kif);
884 error = copyout(kif, (void *)arg, sizeof(*kif));
889 FILEDESC_SUNLOCK(fdp);
904 getmaxfd(struct thread *td)
907 return (min((int)lim_cur(td, RLIMIT_NOFILE), maxfilesperproc));
911 * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD).
914 kern_dup(struct thread *td, u_int mode, int flags, int old, int new)
916 struct filedesc *fdp;
917 struct filedescent *oldfde, *newfde;
919 struct file *delfp, *oldfp;
920 u_long *oioctls, *nioctls;
927 MPASS((flags & ~(FDDUP_FLAG_CLOEXEC)) == 0);
928 MPASS(mode < FDDUP_LASTMODE);
931 /* XXXRW: if (flags & FDDUP_FIXED) AUDIT_ARG_FD2(new); */
934 * Verify we have a valid descriptor to dup from and possibly to
935 * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should
936 * return EINVAL when the new descriptor is out of bounds.
941 return (mode == FDDUP_FCNTL ? EINVAL : EBADF);
942 maxfd = getmaxfd(td);
944 return (mode == FDDUP_FCNTL ? EINVAL : EBADF);
948 if (fget_locked(fdp, old) == NULL)
950 if ((mode == FDDUP_FIXED || mode == FDDUP_MUSTREPLACE) && old == new) {
951 td->td_retval[0] = new;
952 if (flags & FDDUP_FLAG_CLOEXEC)
953 fdp->fd_ofiles[new].fde_flags |= UF_EXCLOSE;
958 oldfde = &fdp->fd_ofiles[old];
959 oldfp = oldfde->fde_file;
964 * If the caller specified a file descriptor, make sure the file
965 * table is large enough to hold it, and grab it. Otherwise, just
966 * allocate a new descriptor the usual way.
971 if ((error = fdalloc(td, new, &new)) != 0) {
976 case FDDUP_MUSTREPLACE:
977 /* Target file descriptor must exist. */
978 if (fget_locked(fdp, new) == NULL) {
984 if (new >= fdp->fd_nfiles) {
986 * The resource limits are here instead of e.g.
987 * fdalloc(), because the file descriptor table may be
988 * shared between processes, so we can't really use
989 * racct_add()/racct_sub(). Instead of counting the
990 * number of actually allocated descriptors, just put
991 * the limit on the size of the file descriptor table.
994 if (RACCT_ENABLED()) {
995 error = racct_set_unlocked(p, RACCT_NOFILE, new + 1);
1003 fdgrowtable_exp(fdp, new + 1);
1005 if (!fdisused(fdp, new))
1009 KASSERT(0, ("%s unsupported mode %d", __func__, mode));
1012 KASSERT(old != new, ("new fd is same as old"));
1014 /* Refetch oldfde because the table may have grown and old one freed. */
1015 oldfde = &fdp->fd_ofiles[old];
1016 KASSERT(oldfp == oldfde->fde_file,
1017 ("fdt_ofiles shift from growth observed at fd %d",
1020 newfde = &fdp->fd_ofiles[new];
1021 delfp = newfde->fde_file;
1023 nioctls = filecaps_copy_prep(&oldfde->fde_caps);
1026 * Duplicate the source descriptor.
1029 seqc_write_begin(&newfde->fde_seqc);
1031 oioctls = filecaps_free_prep(&newfde->fde_caps);
1032 memcpy(newfde, oldfde, fde_change_size);
1033 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps,
1035 if ((flags & FDDUP_FLAG_CLOEXEC) != 0)
1036 newfde->fde_flags = oldfde->fde_flags | UF_EXCLOSE;
1038 newfde->fde_flags = oldfde->fde_flags & ~UF_EXCLOSE;
1040 seqc_write_end(&newfde->fde_seqc);
1042 td->td_retval[0] = new;
1046 if (delfp != NULL) {
1047 (void) closefp(fdp, new, delfp, td, true, false);
1048 FILEDESC_UNLOCK_ASSERT(fdp);
1051 FILEDESC_XUNLOCK(fdp);
1054 filecaps_free_finish(oioctls);
1059 sigiofree(struct sigio *sigio)
1061 crfree(sigio->sio_ucred);
1062 free(sigio, M_SIGIO);
1065 static struct sigio *
1066 funsetown_locked(struct sigio *sigio)
1071 SIGIO_ASSERT_LOCKED();
1075 *sigio->sio_myref = NULL;
1076 if (sigio->sio_pgid < 0) {
1077 pg = sigio->sio_pgrp;
1079 SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, sio_pgsigio);
1082 p = sigio->sio_proc;
1084 SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, sio_pgsigio);
1091 * If sigio is on the list associated with a process or process group,
1092 * disable signalling from the device, remove sigio from the list and
1096 funsetown(struct sigio **sigiop)
1098 struct sigio *sigio;
1100 /* Racy check, consumers must provide synchronization. */
1101 if (*sigiop == NULL)
1105 sigio = funsetown_locked(*sigiop);
1112 * Free a list of sigio structures. The caller must ensure that new sigio
1113 * structures cannot be added after this point. For process groups this is
1114 * guaranteed using the proctree lock; for processes, the P_WEXIT flag serves
1118 funsetownlst(struct sigiolst *sigiolst)
1122 struct sigio *sigio, *tmp;
1125 sigio = SLIST_FIRST(sigiolst);
1133 sigio = SLIST_FIRST(sigiolst);
1134 if (sigio == NULL) {
1140 * Every entry of the list should belong to a single proc or pgrp.
1142 if (sigio->sio_pgid < 0) {
1143 pg = sigio->sio_pgrp;
1144 sx_assert(&proctree_lock, SX_XLOCKED);
1146 } else /* if (sigio->sio_pgid > 0) */ {
1147 p = sigio->sio_proc;
1149 KASSERT((p->p_flag & P_WEXIT) != 0,
1150 ("%s: process %p is not exiting", __func__, p));
1153 SLIST_FOREACH(sigio, sigiolst, sio_pgsigio) {
1154 *sigio->sio_myref = NULL;
1156 KASSERT(sigio->sio_pgid < 0,
1157 ("Proc sigio in pgrp sigio list"));
1158 KASSERT(sigio->sio_pgrp == pg,
1159 ("Bogus pgrp in sigio list"));
1160 } else /* if (p != NULL) */ {
1161 KASSERT(sigio->sio_pgid > 0,
1162 ("Pgrp sigio in proc sigio list"));
1163 KASSERT(sigio->sio_proc == p,
1164 ("Bogus proc in sigio list"));
1174 SLIST_FOREACH_SAFE(sigio, sigiolst, sio_pgsigio, tmp)
1179 * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg).
1181 * After permission checking, add a sigio structure to the sigio list for
1182 * the process or process group.
1185 fsetown(pid_t pgid, struct sigio **sigiop)
1189 struct sigio *osigio, *sigio;
1197 sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK);
1198 sigio->sio_pgid = pgid;
1199 sigio->sio_ucred = crhold(curthread->td_ucred);
1200 sigio->sio_myref = sigiop;
1204 ret = pget(pgid, PGET_NOTWEXIT | PGET_NOTID | PGET_HOLD, &proc);
1206 osigio = funsetown_locked(*sigiop);
1210 if ((proc->p_flag & P_WEXIT) != 0) {
1212 } else if (proc->p_session !=
1213 curthread->td_proc->p_session) {
1215 * Policy - Don't allow a process to FSETOWN a
1216 * process in another session.
1218 * Remove this test to allow maximum flexibility
1219 * or restrict FSETOWN to the current process or
1220 * process group for maximum safety.
1224 sigio->sio_proc = proc;
1225 SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio,
1230 } else /* if (pgid < 0) */ {
1231 sx_slock(&proctree_lock);
1233 osigio = funsetown_locked(*sigiop);
1234 pgrp = pgfind(-pgid);
1238 if (pgrp->pg_session != curthread->td_proc->p_session) {
1240 * Policy - Don't allow a process to FSETOWN a
1241 * process in another session.
1243 * Remove this test to allow maximum flexibility
1244 * or restrict FSETOWN to the current process or
1245 * process group for maximum safety.
1249 sigio->sio_pgrp = pgrp;
1250 SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio,
1255 sx_sunlock(&proctree_lock);
1266 * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg).
1269 fgetown(struct sigio **sigiop)
1274 pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0;
1280 closefp_impl(struct filedesc *fdp, int fd, struct file *fp, struct thread *td,
1285 FILEDESC_XLOCK_ASSERT(fdp);
1288 * We now hold the fp reference that used to be owned by the
1289 * descriptor array. We have to unlock the FILEDESC *AFTER*
1290 * knote_fdclose to prevent a race of the fd getting opened, a knote
1291 * added, and deleteing a knote for the new fd.
1293 if (__predict_false(!TAILQ_EMPTY(&fdp->fd_kqlist)))
1294 knote_fdclose(td, fd);
1297 * We need to notify mqueue if the object is of type mqueue.
1299 if (__predict_false(fp->f_type == DTYPE_MQUEUE))
1300 mq_fdclose(td, fd, fp);
1301 FILEDESC_XUNLOCK(fdp);
1304 if (AUDITING_TD(td) && audit)
1305 audit_sysclose(td, fd, fp);
1307 error = closef(fp, td);
1310 * All paths leading up to closefp() will have already removed or
1311 * replaced the fd in the filedesc table, so a restart would not
1312 * operate on the same file.
1314 if (error == ERESTART)
1321 closefp_hl(struct filedesc *fdp, int fd, struct file *fp, struct thread *td,
1322 bool holdleaders, bool audit)
1326 FILEDESC_XLOCK_ASSERT(fdp);
1329 if (td->td_proc->p_fdtol != NULL) {
1331 * Ask fdfree() to sleep to ensure that all relevant
1332 * process leaders can be traversed in closef().
1334 fdp->fd_holdleaderscount++;
1336 holdleaders = false;
1340 error = closefp_impl(fdp, fd, fp, td, audit);
1342 FILEDESC_XLOCK(fdp);
1343 fdp->fd_holdleaderscount--;
1344 if (fdp->fd_holdleaderscount == 0 &&
1345 fdp->fd_holdleaderswakeup != 0) {
1346 fdp->fd_holdleaderswakeup = 0;
1347 wakeup(&fdp->fd_holdleaderscount);
1349 FILEDESC_XUNLOCK(fdp);
1355 closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td,
1356 bool holdleaders, bool audit)
1359 FILEDESC_XLOCK_ASSERT(fdp);
1361 if (__predict_false(td->td_proc->p_fdtol != NULL)) {
1362 return (closefp_hl(fdp, fd, fp, td, holdleaders, audit));
1364 return (closefp_impl(fdp, fd, fp, td, audit));
1369 * Close a file descriptor.
1371 #ifndef _SYS_SYSPROTO_H_
1378 sys_close(struct thread *td, struct close_args *uap)
1381 return (kern_close(td, uap->fd));
1385 kern_close(struct thread *td, int fd)
1387 struct filedesc *fdp;
1390 fdp = td->td_proc->p_fd;
1392 FILEDESC_XLOCK(fdp);
1393 if ((fp = fget_locked(fdp, fd)) == NULL) {
1394 FILEDESC_XUNLOCK(fdp);
1399 /* closefp() drops the FILEDESC lock for us. */
1400 return (closefp(fdp, fd, fp, td, true, true));
1404 close_range_cloexec(struct thread *td, u_int lowfd, u_int highfd)
1406 struct filedesc *fdp;
1407 struct fdescenttbl *fdt;
1408 struct filedescent *fde;
1411 fdp = td->td_proc->p_fd;
1412 FILEDESC_XLOCK(fdp);
1413 fdt = atomic_load_ptr(&fdp->fd_files);
1414 highfd = MIN(highfd, fdt->fdt_nfiles - 1);
1416 if (__predict_false(fd > highfd)) {
1419 for (; fd <= highfd; fd++) {
1420 fde = &fdt->fdt_ofiles[fd];
1421 if (fde->fde_file != NULL)
1422 fde->fde_flags |= UF_EXCLOSE;
1425 FILEDESC_XUNLOCK(fdp);
1430 close_range_impl(struct thread *td, u_int lowfd, u_int highfd)
1432 struct filedesc *fdp;
1433 const struct fdescenttbl *fdt;
1437 fdp = td->td_proc->p_fd;
1438 FILEDESC_XLOCK(fdp);
1439 fdt = atomic_load_ptr(&fdp->fd_files);
1440 highfd = MIN(highfd, fdt->fdt_nfiles - 1);
1442 if (__predict_false(fd > highfd)) {
1446 fp = fdt->fdt_ofiles[fd].fde_file;
1452 (void) closefp(fdp, fd, fp, td, true, true);
1455 FILEDESC_XLOCK(fdp);
1456 fdt = atomic_load_ptr(&fdp->fd_files);
1461 FILEDESC_XUNLOCK(fdp);
1467 kern_close_range(struct thread *td, int flags, u_int lowfd, u_int highfd)
1471 * Check this prior to clamping; closefrom(3) with only fd 0, 1, and 2
1472 * open should not be a usage error. From a close_range() perspective,
1473 * close_range(3, ~0U, 0) in the same scenario should also likely not
1474 * be a usage error as all fd above 3 are in-fact already closed.
1476 if (highfd < lowfd) {
1480 if ((flags & CLOSE_RANGE_CLOEXEC) != 0)
1481 return (close_range_cloexec(td, lowfd, highfd));
1483 return (close_range_impl(td, lowfd, highfd));
1486 #ifndef _SYS_SYSPROTO_H_
1487 struct close_range_args {
1494 sys_close_range(struct thread *td, struct close_range_args *uap)
1497 AUDIT_ARG_FD(uap->lowfd);
1498 AUDIT_ARG_CMD(uap->highfd);
1499 AUDIT_ARG_FFLAGS(uap->flags);
1501 if ((uap->flags & ~(CLOSE_RANGE_CLOEXEC)) != 0)
1503 return (kern_close_range(td, uap->flags, uap->lowfd, uap->highfd));
1506 #ifdef COMPAT_FREEBSD12
1508 * Close open file descriptors.
1510 #ifndef _SYS_SYSPROTO_H_
1511 struct freebsd12_closefrom_args {
1517 freebsd12_closefrom(struct thread *td, struct freebsd12_closefrom_args *uap)
1521 AUDIT_ARG_FD(uap->lowfd);
1524 * Treat negative starting file descriptor values identical to
1525 * closefrom(0) which closes all files.
1527 lowfd = MAX(0, uap->lowfd);
1528 return (kern_close_range(td, 0, lowfd, ~0U));
1530 #endif /* COMPAT_FREEBSD12 */
1532 #if defined(COMPAT_43)
1534 * Return status information about a file descriptor.
1536 #ifndef _SYS_SYSPROTO_H_
1537 struct ofstat_args {
1544 ofstat(struct thread *td, struct ofstat_args *uap)
1550 error = kern_fstat(td, uap->fd, &ub);
1553 error = copyout(&oub, uap->sb, sizeof(oub));
1557 #endif /* COMPAT_43 */
1559 #if defined(COMPAT_FREEBSD11)
1561 freebsd11_fstat(struct thread *td, struct freebsd11_fstat_args *uap)
1564 struct freebsd11_stat osb;
1567 error = kern_fstat(td, uap->fd, &sb);
1570 error = freebsd11_cvtstat(&sb, &osb);
1572 error = copyout(&osb, uap->sb, sizeof(osb));
1575 #endif /* COMPAT_FREEBSD11 */
1578 * Return status information about a file descriptor.
1580 #ifndef _SYS_SYSPROTO_H_
1588 sys_fstat(struct thread *td, struct fstat_args *uap)
1593 error = kern_fstat(td, uap->fd, &ub);
1595 error = copyout(&ub, uap->sb, sizeof(ub));
1600 kern_fstat(struct thread *td, int fd, struct stat *sbp)
1607 error = fget(td, fd, &cap_fstat_rights, &fp);
1608 if (__predict_false(error != 0))
1611 AUDIT_ARG_FILE(td->td_proc, fp);
1613 error = fo_stat(fp, sbp, td->td_ucred, td);
1615 #ifdef __STAT_TIME_T_EXT
1616 sbp->st_atim_ext = 0;
1617 sbp->st_mtim_ext = 0;
1618 sbp->st_ctim_ext = 0;
1619 sbp->st_btim_ext = 0;
1622 if (KTRPOINT(td, KTR_STRUCT))
1623 ktrstat_error(sbp, error);
1628 #if defined(COMPAT_FREEBSD11)
1630 * Return status information about a file descriptor.
1632 #ifndef _SYS_SYSPROTO_H_
1633 struct freebsd11_nfstat_args {
1640 freebsd11_nfstat(struct thread *td, struct freebsd11_nfstat_args *uap)
1646 error = kern_fstat(td, uap->fd, &ub);
1648 freebsd11_cvtnstat(&ub, &nub);
1649 error = copyout(&nub, uap->sb, sizeof(nub));
1653 #endif /* COMPAT_FREEBSD11 */
1656 * Return pathconf information about a file descriptor.
1658 #ifndef _SYS_SYSPROTO_H_
1659 struct fpathconf_args {
1666 sys_fpathconf(struct thread *td, struct fpathconf_args *uap)
1671 error = kern_fpathconf(td, uap->fd, uap->name, &value);
1673 td->td_retval[0] = value;
1678 kern_fpathconf(struct thread *td, int fd, int name, long *valuep)
1684 error = fget(td, fd, &cap_fpathconf_rights, &fp);
1688 if (name == _PC_ASYNC_IO) {
1689 *valuep = _POSIX_ASYNCHRONOUS_IO;
1694 vn_lock(vp, LK_SHARED | LK_RETRY);
1695 error = VOP_PATHCONF(vp, name, valuep);
1697 } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) {
1698 if (name != _PC_PIPE_BUF) {
1713 * Copy filecaps structure allocating memory for ioctls array if needed.
1715 * The last parameter indicates whether the fdtable is locked. If it is not and
1716 * ioctls are encountered, copying fails and the caller must lock the table.
1718 * Note that if the table was not locked, the caller has to check the relevant
1719 * sequence counter to determine whether the operation was successful.
1722 filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked)
1726 if (src->fc_ioctls != NULL && !locked)
1728 memcpy(dst, src, sizeof(*src));
1729 if (src->fc_ioctls == NULL)
1732 KASSERT(src->fc_nioctls > 0,
1733 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1735 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1736 dst->fc_ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1737 memcpy(dst->fc_ioctls, src->fc_ioctls, size);
1742 filecaps_copy_prep(const struct filecaps *src)
1747 if (__predict_true(src->fc_ioctls == NULL))
1750 KASSERT(src->fc_nioctls > 0,
1751 ("fc_ioctls != NULL, but fc_nioctls=%hd", src->fc_nioctls));
1753 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1754 ioctls = malloc(size, M_FILECAPS, M_WAITOK);
1759 filecaps_copy_finish(const struct filecaps *src, struct filecaps *dst,
1765 if (__predict_true(src->fc_ioctls == NULL)) {
1766 MPASS(ioctls == NULL);
1770 size = sizeof(src->fc_ioctls[0]) * src->fc_nioctls;
1771 dst->fc_ioctls = ioctls;
1772 bcopy(src->fc_ioctls, dst->fc_ioctls, size);
1776 * Move filecaps structure to the new place and clear the old place.
1779 filecaps_move(struct filecaps *src, struct filecaps *dst)
1783 bzero(src, sizeof(*src));
1787 * Fill the given filecaps structure with full rights.
1790 filecaps_fill(struct filecaps *fcaps)
1793 CAP_ALL(&fcaps->fc_rights);
1794 fcaps->fc_ioctls = NULL;
1795 fcaps->fc_nioctls = -1;
1796 fcaps->fc_fcntls = CAP_FCNTL_ALL;
1800 * Free memory allocated within filecaps structure.
1803 filecaps_free_ioctl(struct filecaps *fcaps)
1806 free(fcaps->fc_ioctls, M_FILECAPS);
1807 fcaps->fc_ioctls = NULL;
1811 filecaps_free(struct filecaps *fcaps)
1814 filecaps_free_ioctl(fcaps);
1815 bzero(fcaps, sizeof(*fcaps));
1819 filecaps_free_prep(struct filecaps *fcaps)
1823 ioctls = fcaps->fc_ioctls;
1824 bzero(fcaps, sizeof(*fcaps));
1829 filecaps_free_finish(u_long *ioctls)
1832 free(ioctls, M_FILECAPS);
1836 * Validate the given filecaps structure.
1839 filecaps_validate(const struct filecaps *fcaps, const char *func)
1842 KASSERT(cap_rights_is_valid(&fcaps->fc_rights),
1843 ("%s: invalid rights", func));
1844 KASSERT((fcaps->fc_fcntls & ~CAP_FCNTL_ALL) == 0,
1845 ("%s: invalid fcntls", func));
1846 KASSERT(fcaps->fc_fcntls == 0 ||
1847 cap_rights_is_set(&fcaps->fc_rights, CAP_FCNTL),
1848 ("%s: fcntls without CAP_FCNTL", func));
1850 * open calls without WANTIOCTLCAPS free caps but leave the counter
1853 KASSERT(fcaps->fc_ioctls != NULL ? fcaps->fc_nioctls > 0 :
1854 (fcaps->fc_nioctls == -1 || fcaps->fc_nioctls == 0),
1855 ("%s: invalid ioctls", func));
1857 KASSERT(fcaps->fc_nioctls == 0 ||
1858 cap_rights_is_set(&fcaps->fc_rights, CAP_IOCTL),
1859 ("%s: ioctls without CAP_IOCTL", func));
1863 fdgrowtable_exp(struct filedesc *fdp, int nfd)
1867 FILEDESC_XLOCK_ASSERT(fdp);
1869 nfd1 = fdp->fd_nfiles * 2;
1872 fdgrowtable(fdp, nfd1);
1876 * Grow the file table to accommodate (at least) nfd descriptors.
1879 fdgrowtable(struct filedesc *fdp, int nfd)
1881 struct filedesc0 *fdp0;
1882 struct freetable *ft;
1883 struct fdescenttbl *ntable;
1884 struct fdescenttbl *otable;
1885 int nnfiles, onfiles;
1886 NDSLOTTYPE *nmap, *omap;
1888 KASSERT(fdp->fd_nfiles > 0, ("zero-length file table"));
1890 /* save old values */
1891 onfiles = fdp->fd_nfiles;
1892 otable = fdp->fd_files;
1895 /* compute the size of the new table */
1896 nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */
1897 if (nnfiles <= onfiles)
1898 /* the table is already large enough */
1902 * Allocate a new table. We need enough space for the number of
1903 * entries, file entries themselves and the struct freetable we will use
1904 * when we decommission the table and place it on the freelist.
1905 * We place the struct freetable in the middle so we don't have
1906 * to worry about padding.
1908 ntable = malloc(offsetof(struct fdescenttbl, fdt_ofiles) +
1909 nnfiles * sizeof(ntable->fdt_ofiles[0]) +
1910 sizeof(struct freetable),
1911 M_FILEDESC, M_ZERO | M_WAITOK);
1912 /* copy the old data */
1913 ntable->fdt_nfiles = nnfiles;
1914 memcpy(ntable->fdt_ofiles, otable->fdt_ofiles,
1915 onfiles * sizeof(ntable->fdt_ofiles[0]));
1918 * Allocate a new map only if the old is not large enough. It will
1919 * grow at a slower rate than the table as it can map more
1920 * entries than the table can hold.
1922 if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) {
1923 nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, M_FILEDESC,
1925 /* copy over the old data and update the pointer */
1926 memcpy(nmap, omap, NDSLOTS(onfiles) * sizeof(*omap));
1931 * Make sure that ntable is correctly initialized before we replace
1932 * fd_files poiner. Otherwise fget_unlocked() may see inconsistent
1935 atomic_store_rel_ptr((volatile void *)&fdp->fd_files, (uintptr_t)ntable);
1938 * Free the old file table when not shared by other threads or processes.
1939 * The old file table is considered to be shared when either are true:
1940 * - The process has more than one thread.
1941 * - The file descriptor table has been shared via fdshare().
1943 * When shared, the old file table will be placed on a freelist
1944 * which will be processed when the struct filedesc is released.
1946 * Note that if onfiles == NDFILE, we're dealing with the original
1947 * static allocation contained within (struct filedesc0 *)fdp,
1948 * which must not be freed.
1950 if (onfiles > NDFILE) {
1952 * Note we may be called here from fdinit while allocating a
1953 * table for a new process in which case ->p_fd points
1956 if (curproc->p_fd != fdp || FILEDESC_IS_ONLY_USER(fdp)) {
1957 free(otable, M_FILEDESC);
1959 ft = (struct freetable *)&otable->fdt_ofiles[onfiles];
1960 fdp0 = (struct filedesc0 *)fdp;
1961 ft->ft_table = otable;
1962 SLIST_INSERT_HEAD(&fdp0->fd_free, ft, ft_next);
1966 * The map does not have the same possibility of threads still
1967 * holding references to it. So always free it as long as it
1968 * does not reference the original static allocation.
1970 if (NDSLOTS(onfiles) > NDSLOTS(NDFILE))
1971 free(omap, M_FILEDESC);
1975 * Allocate a file descriptor for the process.
1978 fdalloc(struct thread *td, int minfd, int *result)
1980 struct proc *p = td->td_proc;
1981 struct filedesc *fdp = p->p_fd;
1982 int fd, maxfd, allocfd;
1987 FILEDESC_XLOCK_ASSERT(fdp);
1989 if (fdp->fd_freefile > minfd)
1990 minfd = fdp->fd_freefile;
1992 maxfd = getmaxfd(td);
1995 * Search the bitmap for a free descriptor starting at minfd.
1996 * If none is found, grow the file table.
1998 fd = fd_first_free(fdp, minfd, fdp->fd_nfiles);
1999 if (__predict_false(fd >= maxfd))
2001 if (__predict_false(fd >= fdp->fd_nfiles)) {
2002 allocfd = min(fd * 2, maxfd);
2004 if (RACCT_ENABLED()) {
2005 error = racct_set_unlocked(p, RACCT_NOFILE, allocfd);
2011 * fd is already equal to first free descriptor >= minfd, so
2012 * we only need to grow the table and we are done.
2014 fdgrowtable_exp(fdp, allocfd);
2018 * Perform some sanity checks, then mark the file descriptor as
2019 * used and return it to the caller.
2021 KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles),
2022 ("invalid descriptor %d", fd));
2023 KASSERT(!fdisused(fdp, fd),
2024 ("fd_first_free() returned non-free descriptor"));
2025 KASSERT(fdp->fd_ofiles[fd].fde_file == NULL,
2026 ("file descriptor isn't free"));
2033 * Allocate n file descriptors for the process.
2036 fdallocn(struct thread *td, int minfd, int *fds, int n)
2038 struct proc *p = td->td_proc;
2039 struct filedesc *fdp = p->p_fd;
2042 FILEDESC_XLOCK_ASSERT(fdp);
2044 for (i = 0; i < n; i++)
2045 if (fdalloc(td, 0, &fds[i]) != 0)
2049 for (i--; i >= 0; i--)
2050 fdunused(fdp, fds[i]);
2058 * Create a new open file structure and allocate a file descriptor for the
2059 * process that refers to it. We add one reference to the file for the
2060 * descriptor table and one reference for resultfp. This is to prevent us
2061 * being preempted and the entry in the descriptor table closed after we
2062 * release the FILEDESC lock.
2065 falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags,
2066 struct filecaps *fcaps)
2071 MPASS(resultfp != NULL);
2072 MPASS(resultfd != NULL);
2074 error = _falloc_noinstall(td, &fp, 2);
2075 if (__predict_false(error != 0)) {
2079 error = finstall_refed(td, fp, &fd, flags, fcaps);
2080 if (__predict_false(error != 0)) {
2081 falloc_abort(td, fp);
2092 * Create a new open file structure without allocating a file descriptor.
2095 _falloc_noinstall(struct thread *td, struct file **resultfp, u_int n)
2098 int maxuserfiles = maxfiles - (maxfiles / 20);
2100 static struct timeval lastfail;
2103 KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__));
2106 openfiles_new = atomic_fetchadd_int(&openfiles, 1) + 1;
2107 if ((openfiles_new >= maxuserfiles &&
2108 priv_check(td, PRIV_MAXFILES) != 0) ||
2109 openfiles_new >= maxfiles) {
2110 atomic_subtract_int(&openfiles, 1);
2111 if (ppsratecheck(&lastfail, &curfail, 1)) {
2112 printf("kern.maxfiles limit exceeded by uid %i, (%s) "
2113 "please see tuning(7).\n", td->td_ucred->cr_ruid, td->td_proc->p_comm);
2117 fp = uma_zalloc(file_zone, M_WAITOK);
2118 bzero(fp, sizeof(*fp));
2119 refcount_init(&fp->f_count, n);
2120 fp->f_cred = crhold(td->td_ucred);
2121 fp->f_ops = &badfileops;
2127 falloc_abort(struct thread *td, struct file *fp)
2131 * For assertion purposes.
2133 refcount_init(&fp->f_count, 0);
2138 * Install a file in a file descriptor table.
2141 _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags,
2142 struct filecaps *fcaps)
2144 struct filedescent *fde;
2148 filecaps_validate(fcaps, __func__);
2149 FILEDESC_XLOCK_ASSERT(fdp);
2151 fde = &fdp->fd_ofiles[fd];
2153 seqc_write_begin(&fde->fde_seqc);
2156 fde->fde_flags = (flags & O_CLOEXEC) != 0 ? UF_EXCLOSE : 0;
2158 filecaps_move(fcaps, &fde->fde_caps);
2160 filecaps_fill(&fde->fde_caps);
2162 seqc_write_end(&fde->fde_seqc);
2167 finstall_refed(struct thread *td, struct file *fp, int *fd, int flags,
2168 struct filecaps *fcaps)
2170 struct filedesc *fdp = td->td_proc->p_fd;
2175 FILEDESC_XLOCK(fdp);
2176 error = fdalloc(td, 0, fd);
2177 if (__predict_true(error == 0)) {
2178 _finstall(fdp, fp, *fd, flags, fcaps);
2180 FILEDESC_XUNLOCK(fdp);
2185 finstall(struct thread *td, struct file *fp, int *fd, int flags,
2186 struct filecaps *fcaps)
2194 error = finstall_refed(td, fp, fd, flags, fcaps);
2195 if (__predict_false(error != 0)) {
2202 * Build a new filedesc structure from another.
2204 * If fdp is not NULL, return with it shared locked.
2207 fdinit(struct filedesc *fdp, bool prepfiles, int *lastfile)
2209 struct filedesc0 *newfdp0;
2210 struct filedesc *newfdp;
2213 MPASS(lastfile != NULL);
2215 MPASS(lastfile == NULL);
2217 newfdp0 = uma_zalloc(filedesc0_zone, M_WAITOK | M_ZERO);
2218 newfdp = &newfdp0->fd_fd;
2220 /* Create the file descriptor table. */
2221 FILEDESC_LOCK_INIT(newfdp);
2222 refcount_init(&newfdp->fd_refcnt, 1);
2223 refcount_init(&newfdp->fd_holdcnt, 1);
2224 newfdp->fd_map = newfdp0->fd_dmap;
2225 newfdp->fd_files = (struct fdescenttbl *)&newfdp0->fd_dfiles;
2226 newfdp->fd_files->fdt_nfiles = NDFILE;
2231 FILEDESC_SLOCK(fdp);
2233 FILEDESC_SUNLOCK(fdp);
2238 *lastfile = fdlastfile(fdp);
2239 if (*lastfile < newfdp->fd_nfiles)
2241 FILEDESC_SUNLOCK(fdp);
2242 fdgrowtable(newfdp, *lastfile + 1);
2243 FILEDESC_SLOCK(fdp);
2250 * Build a pwddesc structure from another.
2251 * Copy the current, root, and jail root vnode references.
2253 * If pdp is not NULL, return with it shared locked.
2256 pdinit(struct pwddesc *pdp, bool keeplock)
2258 struct pwddesc *newpdp;
2261 newpdp = malloc(sizeof(*newpdp), M_PWDDESC, M_WAITOK | M_ZERO);
2263 PWDDESC_LOCK_INIT(newpdp);
2264 refcount_init(&newpdp->pd_refcount, 1);
2265 newpdp->pd_cmask = CMASK;
2268 newpwd = pwd_alloc();
2269 smr_serialized_store(&newpdp->pd_pwd, newpwd, true);
2274 newpwd = pwd_hold_pwddesc(pdp);
2275 smr_serialized_store(&newpdp->pd_pwd, newpwd, true);
2277 PWDDESC_XUNLOCK(pdp);
2282 * Hold either filedesc or pwddesc of the passed process.
2284 * The process lock is used to synchronize against the target exiting and
2287 * Clearing can be ilustrated in 3 steps:
2288 * 1. set the pointer to NULL. Either routine can race against it, hence
2290 * 2. observe the process lock as not taken. Until then fdhold/pdhold can
2291 * race to either still see the pointer or find NULL. It is still safe to
2292 * grab a reference as clearing is stalled.
2293 * 3. after the lock is observed as not taken, any fdhold/pdhold calls are
2294 * guaranteed to see NULL, making it safe to finish clearing
2296 static struct filedesc *
2297 fdhold(struct proc *p)
2299 struct filedesc *fdp;
2301 PROC_LOCK_ASSERT(p, MA_OWNED);
2302 fdp = atomic_load_ptr(&p->p_fd);
2304 refcount_acquire(&fdp->fd_holdcnt);
2308 static struct pwddesc *
2309 pdhold(struct proc *p)
2311 struct pwddesc *pdp;
2313 PROC_LOCK_ASSERT(p, MA_OWNED);
2314 pdp = atomic_load_ptr(&p->p_pd);
2316 refcount_acquire(&pdp->pd_refcount);
2321 fddrop(struct filedesc *fdp)
2324 if (refcount_load(&fdp->fd_holdcnt) > 1) {
2325 if (refcount_release(&fdp->fd_holdcnt) == 0)
2329 FILEDESC_LOCK_DESTROY(fdp);
2330 uma_zfree(filedesc0_zone, fdp);
2334 pddrop(struct pwddesc *pdp)
2338 if (refcount_release_if_not_last(&pdp->pd_refcount))
2342 if (refcount_release(&pdp->pd_refcount) == 0) {
2343 PWDDESC_XUNLOCK(pdp);
2346 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
2348 PWDDESC_XUNLOCK(pdp);
2351 PWDDESC_LOCK_DESTROY(pdp);
2352 free(pdp, M_PWDDESC);
2356 * Share a filedesc structure.
2359 fdshare(struct filedesc *fdp)
2362 refcount_acquire(&fdp->fd_refcnt);
2367 * Share a pwddesc structure.
2370 pdshare(struct pwddesc *pdp)
2372 refcount_acquire(&pdp->pd_refcount);
2377 * Unshare a filedesc structure, if necessary by making a copy
2380 fdunshare(struct thread *td)
2382 struct filedesc *tmp;
2383 struct proc *p = td->td_proc;
2385 if (refcount_load(&p->p_fd->fd_refcnt) == 1)
2388 tmp = fdcopy(p->p_fd);
2394 * Unshare a pwddesc structure.
2397 pdunshare(struct thread *td)
2399 struct pwddesc *pdp;
2404 if (p->p_pd->pd_refcount == 1)
2407 pdp = pdcopy(p->p_pd);
2413 fdinstall_remapped(struct thread *td, struct filedesc *fdp)
2417 td->td_proc->p_fd = fdp;
2421 * Copy a filedesc structure. A NULL pointer in returns a NULL reference,
2422 * this is to ease callers, not catch errors.
2425 fdcopy(struct filedesc *fdp)
2427 struct filedesc *newfdp;
2428 struct filedescent *nfde, *ofde;
2433 newfdp = fdinit(fdp, true, &lastfile);
2434 /* copy all passable descriptors (i.e. not kqueue) */
2435 newfdp->fd_freefile = -1;
2436 for (i = 0; i <= lastfile; ++i) {
2437 ofde = &fdp->fd_ofiles[i];
2438 if (ofde->fde_file == NULL ||
2439 (ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0 ||
2440 !fhold(ofde->fde_file)) {
2441 if (newfdp->fd_freefile == -1)
2442 newfdp->fd_freefile = i;
2445 nfde = &newfdp->fd_ofiles[i];
2447 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true);
2448 fdused_init(newfdp, i);
2450 if (newfdp->fd_freefile == -1)
2451 newfdp->fd_freefile = i;
2452 FILEDESC_SUNLOCK(fdp);
2457 * Copy a pwddesc structure.
2460 pdcopy(struct pwddesc *pdp)
2462 struct pwddesc *newpdp;
2466 newpdp = pdinit(pdp, true);
2467 newpdp->pd_cmask = pdp->pd_cmask;
2468 PWDDESC_XUNLOCK(pdp);
2473 * Copies a filedesc structure, while remapping all file descriptors
2474 * stored inside using a translation table.
2476 * File descriptors are copied over to the new file descriptor table,
2477 * regardless of whether the close-on-exec flag is set.
2480 fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds,
2481 struct filedesc **ret)
2483 struct filedesc *newfdp;
2484 struct filedescent *nfde, *ofde;
2485 int error, i, lastfile;
2489 newfdp = fdinit(fdp, true, &lastfile);
2490 if (nfds > lastfile + 1) {
2491 /* New table cannot be larger than the old one. */
2495 /* Copy all passable descriptors (i.e. not kqueue). */
2496 newfdp->fd_freefile = nfds;
2497 for (i = 0; i < nfds; ++i) {
2498 if (fds[i] < 0 || fds[i] > lastfile) {
2499 /* File descriptor out of bounds. */
2503 ofde = &fdp->fd_ofiles[fds[i]];
2504 if (ofde->fde_file == NULL) {
2505 /* Unused file descriptor. */
2509 if ((ofde->fde_file->f_ops->fo_flags & DFLAG_PASSABLE) == 0) {
2510 /* File descriptor cannot be passed. */
2514 if (!fhold(ofde->fde_file)) {
2518 nfde = &newfdp->fd_ofiles[i];
2520 filecaps_copy(&ofde->fde_caps, &nfde->fde_caps, true);
2521 fdused_init(newfdp, i);
2523 FILEDESC_SUNLOCK(fdp);
2527 FILEDESC_SUNLOCK(fdp);
2528 fdescfree_remapped(newfdp);
2533 * Clear POSIX style locks. This is only used when fdp looses a reference (i.e.
2534 * one of processes using it exits) and the table used to be shared.
2537 fdclearlocks(struct thread *td)
2539 struct filedesc *fdp;
2540 struct filedesc_to_leader *fdtol;
2550 MPASS(fdtol != NULL);
2552 FILEDESC_XLOCK(fdp);
2553 KASSERT(fdtol->fdl_refcount > 0,
2554 ("filedesc_to_refcount botch: fdl_refcount=%d",
2555 fdtol->fdl_refcount));
2556 if (fdtol->fdl_refcount == 1 &&
2557 (p->p_leader->p_flag & P_ADVLOCK) != 0) {
2558 lastfile = fdlastfile(fdp);
2559 for (i = 0; i <= lastfile; i++) {
2560 fp = fdp->fd_ofiles[i].fde_file;
2561 if (fp == NULL || fp->f_type != DTYPE_VNODE ||
2564 FILEDESC_XUNLOCK(fdp);
2565 lf.l_whence = SEEK_SET;
2568 lf.l_type = F_UNLCK;
2570 (void) VOP_ADVLOCK(vp,
2571 (caddr_t)p->p_leader, F_UNLCK,
2573 FILEDESC_XLOCK(fdp);
2578 if (fdtol->fdl_refcount == 1) {
2579 if (fdp->fd_holdleaderscount > 0 &&
2580 (p->p_leader->p_flag & P_ADVLOCK) != 0) {
2582 * close() or kern_dup() has cleared a reference
2583 * in a shared file descriptor table.
2585 fdp->fd_holdleaderswakeup = 1;
2586 sx_sleep(&fdp->fd_holdleaderscount,
2587 FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0);
2590 if (fdtol->fdl_holdcount > 0) {
2592 * Ensure that fdtol->fdl_leader remains
2593 * valid in closef().
2595 fdtol->fdl_wakeup = 1;
2596 sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK,
2601 fdtol->fdl_refcount--;
2602 if (fdtol->fdl_refcount == 0 &&
2603 fdtol->fdl_holdcount == 0) {
2604 fdtol->fdl_next->fdl_prev = fdtol->fdl_prev;
2605 fdtol->fdl_prev->fdl_next = fdtol->fdl_next;
2609 FILEDESC_XUNLOCK(fdp);
2611 free(fdtol, M_FILEDESC_TO_LEADER);
2615 * Release a filedesc structure.
2618 fdescfree_fds(struct thread *td, struct filedesc *fdp, bool needclose)
2620 struct filedesc0 *fdp0;
2621 struct freetable *ft, *tft;
2622 struct filedescent *fde;
2626 KASSERT(refcount_load(&fdp->fd_refcnt) == 0,
2627 ("%s: fd table %p carries references", __func__, fdp));
2630 * Serialize with threads iterating over the table, if any.
2632 if (refcount_load(&fdp->fd_holdcnt) > 1) {
2633 FILEDESC_XLOCK(fdp);
2634 FILEDESC_XUNLOCK(fdp);
2637 lastfile = fdlastfile_single(fdp);
2638 for (i = 0; i <= lastfile; i++) {
2639 fde = &fdp->fd_ofiles[i];
2644 (void) closef(fp, td);
2650 if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE))
2651 free(fdp->fd_map, M_FILEDESC);
2652 if (fdp->fd_nfiles > NDFILE)
2653 free(fdp->fd_files, M_FILEDESC);
2655 fdp0 = (struct filedesc0 *)fdp;
2656 SLIST_FOREACH_SAFE(ft, &fdp0->fd_free, ft_next, tft)
2657 free(ft->ft_table, M_FILEDESC);
2663 fdescfree(struct thread *td)
2666 struct filedesc *fdp;
2673 if (RACCT_ENABLED())
2674 racct_set_unlocked(p, RACCT_NOFILE, 0);
2677 if (p->p_fdtol != NULL)
2681 * Check fdhold for an explanation.
2683 atomic_store_ptr(&p->p_fd, NULL);
2684 atomic_thread_fence_seq_cst();
2685 PROC_WAIT_UNLOCKED(p);
2687 if (refcount_release(&fdp->fd_refcnt) == 0)
2690 fdescfree_fds(td, fdp, 1);
2694 pdescfree(struct thread *td)
2697 struct pwddesc *pdp;
2704 * Check pdhold for an explanation.
2706 atomic_store_ptr(&p->p_pd, NULL);
2707 atomic_thread_fence_seq_cst();
2708 PROC_WAIT_UNLOCKED(p);
2714 fdescfree_remapped(struct filedesc *fdp)
2717 /* fdescfree_fds() asserts that fd_refcnt == 0. */
2718 if (!refcount_release(&fdp->fd_refcnt))
2719 panic("%s: fd table %p has extra references", __func__, fdp);
2721 fdescfree_fds(curthread, fdp, 0);
2725 * For setugid programs, we don't want to people to use that setugidness
2726 * to generate error messages which write to a file which otherwise would
2727 * otherwise be off-limits to the process. We check for filesystems where
2728 * the vnode can change out from under us after execve (like [lin]procfs).
2730 * Since fdsetugidsafety calls this only for fd 0, 1 and 2, this check is
2731 * sufficient. We also don't check for setugidness since we know we are.
2734 is_unsafe(struct file *fp)
2738 if (fp->f_type != DTYPE_VNODE)
2742 return ((vp->v_vflag & VV_PROCDEP) != 0);
2746 * Make this setguid thing safe, if at all possible.
2749 fdsetugidsafety(struct thread *td)
2751 struct filedesc *fdp;
2755 fdp = td->td_proc->p_fd;
2756 KASSERT(refcount_load(&fdp->fd_refcnt) == 1,
2757 ("the fdtable should not be shared"));
2758 MPASS(fdp->fd_nfiles >= 3);
2759 for (i = 0; i <= 2; i++) {
2760 fp = fdp->fd_ofiles[i].fde_file;
2761 if (fp != NULL && is_unsafe(fp)) {
2762 FILEDESC_XLOCK(fdp);
2763 knote_fdclose(td, i);
2765 * NULL-out descriptor prior to close to avoid
2766 * a race while close blocks.
2769 FILEDESC_XUNLOCK(fdp);
2770 (void) closef(fp, td);
2776 * If a specific file object occupies a specific file descriptor, close the
2777 * file descriptor entry and drop a reference on the file object. This is a
2778 * convenience function to handle a subsequent error in a function that calls
2779 * falloc() that handles the race that another thread might have closed the
2780 * file descriptor out from under the thread creating the file object.
2783 fdclose(struct thread *td, struct file *fp, int idx)
2785 struct filedesc *fdp = td->td_proc->p_fd;
2787 FILEDESC_XLOCK(fdp);
2788 if (fdp->fd_ofiles[idx].fde_file == fp) {
2790 FILEDESC_XUNLOCK(fdp);
2793 FILEDESC_XUNLOCK(fdp);
2797 * Close any files on exec?
2800 fdcloseexec(struct thread *td)
2802 struct filedesc *fdp;
2803 struct filedescent *fde;
2807 fdp = td->td_proc->p_fd;
2808 KASSERT(refcount_load(&fdp->fd_refcnt) == 1,
2809 ("the fdtable should not be shared"));
2810 lastfile = fdlastfile_single(fdp);
2811 for (i = 0; i <= lastfile; i++) {
2812 fde = &fdp->fd_ofiles[i];
2814 if (fp != NULL && (fp->f_type == DTYPE_MQUEUE ||
2815 (fde->fde_flags & UF_EXCLOSE))) {
2816 FILEDESC_XLOCK(fdp);
2818 (void) closefp(fdp, i, fp, td, false, false);
2819 FILEDESC_UNLOCK_ASSERT(fdp);
2825 * It is unsafe for set[ug]id processes to be started with file
2826 * descriptors 0..2 closed, as these descriptors are given implicit
2827 * significance in the Standard C library. fdcheckstd() will create a
2828 * descriptor referencing /dev/null for each of stdin, stdout, and
2829 * stderr that is not already open.
2832 fdcheckstd(struct thread *td)
2834 struct filedesc *fdp;
2836 int i, error, devnull;
2838 fdp = td->td_proc->p_fd;
2839 KASSERT(refcount_load(&fdp->fd_refcnt) == 1,
2840 ("the fdtable should not be shared"));
2841 MPASS(fdp->fd_nfiles >= 3);
2843 for (i = 0; i <= 2; i++) {
2844 if (fdp->fd_ofiles[i].fde_file != NULL)
2847 save = td->td_retval[0];
2848 if (devnull != -1) {
2849 error = kern_dup(td, FDDUP_FIXED, 0, devnull, i);
2851 error = kern_openat(td, AT_FDCWD, "/dev/null",
2852 UIO_SYSSPACE, O_RDWR, 0);
2854 devnull = td->td_retval[0];
2855 KASSERT(devnull == i, ("we didn't get our fd"));
2858 td->td_retval[0] = save;
2866 * Internal form of close. Decrement reference count on file structure.
2867 * Note: td may be NULL when closing a file that was being passed in a
2871 closef(struct file *fp, struct thread *td)
2875 struct filedesc_to_leader *fdtol;
2876 struct filedesc *fdp;
2881 * POSIX record locking dictates that any close releases ALL
2882 * locks owned by this process. This is handled by setting
2883 * a flag in the unlock to free ONLY locks obeying POSIX
2884 * semantics, and not to free BSD-style file locks.
2885 * If the descriptor was in a message, POSIX-style locks
2886 * aren't passed with the descriptor, and the thread pointer
2887 * will be NULL. Callers should be careful only to pass a
2888 * NULL thread pointer when there really is no owning
2889 * context that might have locks, or the locks will be
2892 if (fp->f_type == DTYPE_VNODE) {
2894 if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) {
2895 lf.l_whence = SEEK_SET;
2898 lf.l_type = F_UNLCK;
2899 (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader,
2900 F_UNLCK, &lf, F_POSIX);
2902 fdtol = td->td_proc->p_fdtol;
2903 if (fdtol != NULL) {
2905 * Handle special case where file descriptor table is
2906 * shared between multiple process leaders.
2908 fdp = td->td_proc->p_fd;
2909 FILEDESC_XLOCK(fdp);
2910 for (fdtol = fdtol->fdl_next;
2911 fdtol != td->td_proc->p_fdtol;
2912 fdtol = fdtol->fdl_next) {
2913 if ((fdtol->fdl_leader->p_flag &
2916 fdtol->fdl_holdcount++;
2917 FILEDESC_XUNLOCK(fdp);
2918 lf.l_whence = SEEK_SET;
2921 lf.l_type = F_UNLCK;
2923 (void) VOP_ADVLOCK(vp,
2924 (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf,
2926 FILEDESC_XLOCK(fdp);
2927 fdtol->fdl_holdcount--;
2928 if (fdtol->fdl_holdcount == 0 &&
2929 fdtol->fdl_wakeup != 0) {
2930 fdtol->fdl_wakeup = 0;
2934 FILEDESC_XUNLOCK(fdp);
2937 return (fdrop_close(fp, td));
2941 * Hack for file descriptor passing code.
2944 closef_nothread(struct file *fp)
2951 * Initialize the file pointer with the specified properties.
2953 * The ops are set with release semantics to be certain that the flags, type,
2954 * and data are visible when ops is. This is to prevent ops methods from being
2955 * called with bad data.
2958 finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops)
2963 atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops);
2967 finit_vnode(struct file *fp, u_int flag, void *data, struct fileops *ops)
2969 fp->f_seqcount[UIO_READ] = 1;
2970 fp->f_seqcount[UIO_WRITE] = 1;
2971 finit(fp, (flag & FMASK) | (fp->f_flag & FHASLOCK), DTYPE_VNODE,
2976 fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
2977 struct file **fpp, struct filecaps *havecapsp)
2979 struct filedescent *fde;
2982 FILEDESC_LOCK_ASSERT(fdp);
2985 fde = fdeget_locked(fdp, fd);
2992 error = cap_check(cap_rights_fde_inline(fde), needrightsp);
2997 if (havecapsp != NULL)
2998 filecaps_copy(&fde->fde_caps, havecapsp, true);
3000 *fpp = fde->fde_file;
3008 fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp,
3009 struct file **fpp, struct filecaps *havecapsp)
3011 struct filedesc *fdp = td->td_proc->p_fd;
3013 #ifndef CAPABILITIES
3014 error = fget_unlocked(fdp, fd, needrightsp, fpp);
3015 if (havecapsp != NULL && error == 0)
3016 filecaps_fill(havecapsp);
3023 error = fget_unlocked_seq(fdp, fd, needrightsp, &fp, &seq);
3027 if (havecapsp != NULL) {
3028 if (!filecaps_copy(&fdp->fd_ofiles[fd].fde_caps,
3029 havecapsp, false)) {
3035 if (!fd_modified(fdp, fd, seq))
3044 FILEDESC_SLOCK(fdp);
3045 error = fget_cap_locked(fdp, fd, needrightsp, fpp, havecapsp);
3046 if (error == 0 && !fhold(*fpp))
3048 FILEDESC_SUNLOCK(fdp);
3055 fgetvp_lookup_smr(int fd, struct nameidata *ndp, struct vnode **vpp, bool *fsearch)
3057 const struct filedescent *fde;
3058 const struct fdescenttbl *fdt;
3059 struct filedesc *fdp;
3062 const cap_rights_t *haverights;
3063 cap_rights_t rights;
3066 VFS_SMR_ASSERT_ENTERED();
3068 rights = *ndp->ni_rightsneeded;
3069 cap_rights_set_one(&rights, CAP_LOOKUP);
3071 fdp = curproc->p_fd;
3072 fdt = fdp->fd_files;
3073 if (__predict_false((u_int)fd >= fdt->fdt_nfiles))
3075 seq = seqc_read_notmodify(fd_seqc(fdt, fd));
3076 fde = &fdt->fdt_ofiles[fd];
3077 haverights = cap_rights_fde_inline(fde);
3079 if (__predict_false(fp == NULL))
3081 if (__predict_false(cap_check_inline_transient(haverights, &rights)))
3083 *fsearch = ((fp->f_flag & FSEARCH) != 0);
3085 if (__predict_false(vp == NULL)) {
3088 if (!filecaps_copy(&fde->fde_caps, &ndp->ni_filecaps, false)) {
3092 * Use an acquire barrier to force re-reading of fdt so it is
3093 * refreshed for verification.
3095 atomic_thread_fence_acq();
3096 fdt = fdp->fd_files;
3097 if (__predict_false(!seqc_consistent_nomb(fd_seqc(fdt, fd), seq)))
3100 * If file descriptor doesn't have all rights,
3101 * all lookups relative to it must also be
3102 * strictly relative.
3104 * Not yet supported by fast path.
3107 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights, &rights) ||
3108 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL ||
3109 ndp->ni_filecaps.fc_nioctls != -1) {
3111 ndp->ni_lcf |= NI_LCF_STRICTRELATIVE;
3121 fgetvp_lookup_smr(int fd, struct nameidata *ndp, struct vnode **vpp, bool *fsearch)
3123 const struct fdescenttbl *fdt;
3124 struct filedesc *fdp;
3128 VFS_SMR_ASSERT_ENTERED();
3130 fdp = curproc->p_fd;
3131 fdt = fdp->fd_files;
3132 if (__predict_false((u_int)fd >= fdt->fdt_nfiles))
3134 fp = fdt->fdt_ofiles[fd].fde_file;
3135 if (__predict_false(fp == NULL))
3137 *fsearch = ((fp->f_flag & FSEARCH) != 0);
3139 if (__predict_false(vp == NULL || vp->v_type != VDIR)) {
3143 * Use an acquire barrier to force re-reading of fdt so it is
3144 * refreshed for verification.
3146 atomic_thread_fence_acq();
3147 fdt = fdp->fd_files;
3148 if (__predict_false(fp != fdt->fdt_ofiles[fd].fde_file))
3150 filecaps_fill(&ndp->ni_filecaps);
3157 fgetvp_lookup(int fd, struct nameidata *ndp, struct vnode **vpp)
3162 struct componentname *cnp;
3163 cap_rights_t rights;
3167 rights = *ndp->ni_rightsneeded;
3168 cap_rights_set_one(&rights, CAP_LOOKUP);
3171 error = fget_cap(td, ndp->ni_dirfd, &rights, &fp, &ndp->ni_filecaps);
3172 if (__predict_false(error != 0))
3174 if (__predict_false(fp->f_ops == &badfileops)) {
3179 if (__predict_false(vp == NULL)) {
3185 * XXX does not check for VDIR, handled by namei_setup
3187 if ((fp->f_flag & FSEARCH) != 0)
3188 cnp->cn_flags |= NOEXECCHECK;
3193 * If file descriptor doesn't have all rights,
3194 * all lookups relative to it must also be
3195 * strictly relative.
3198 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights, &rights) ||
3199 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL ||
3200 ndp->ni_filecaps.fc_nioctls != -1) {
3201 ndp->ni_lcf |= NI_LCF_STRICTRELATIVE;
3202 ndp->ni_resflags |= NIRES_STRICTREL;
3207 * TODO: avoid copying ioctl caps if it can be helped to begin with
3209 if ((cnp->cn_flags & WANTIOCTLCAPS) == 0)
3210 filecaps_free_ioctl(&ndp->ni_filecaps);
3216 filecaps_free(&ndp->ni_filecaps);
3222 fget_unlocked_seq(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
3223 struct file **fpp, seqc_t *seqp)
3226 const struct filedescent *fde;
3228 const struct fdescenttbl *fdt;
3232 cap_rights_t haverights;
3236 fdt = fdp->fd_files;
3237 if (__predict_false((u_int)fd >= fdt->fdt_nfiles))
3240 * Fetch the descriptor locklessly. We avoid fdrop() races by
3241 * never raising a refcount above 0. To accomplish this we have
3242 * to use a cmpset loop rather than an atomic_add. The descriptor
3243 * must be re-verified once we acquire a reference to be certain
3244 * that the identity is still correct and we did not lose a race
3245 * due to preemption.
3249 seq = seqc_read_notmodify(fd_seqc(fdt, fd));
3250 fde = &fdt->fdt_ofiles[fd];
3251 haverights = *cap_rights_fde_inline(fde);
3253 if (!seqc_consistent(fd_seqc(fdt, fd), seq))
3256 fp = fdt->fdt_ofiles[fd].fde_file;
3261 error = cap_check_inline(&haverights, needrightsp);
3265 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count))) {
3267 * Force a reload. Other thread could reallocate the
3268 * table before this fd was closed, so it is possible
3269 * that there is a stale fp pointer in cached version.
3271 fdt = atomic_load_ptr(&fdp->fd_files);
3275 * Use an acquire barrier to force re-reading of fdt so it is
3276 * refreshed for verification.
3278 atomic_thread_fence_acq();
3279 fdt = fdp->fd_files;
3281 if (seqc_consistent_nomb(fd_seqc(fdt, fd), seq))
3283 if (fp == fdt->fdt_ofiles[fd].fde_file)
3286 fdrop(fp, curthread);
3298 * See the comments in fget_unlocked_seq for an explanation of how this works.
3300 * This is a simplified variant which bails out to the aforementioned routine
3301 * if anything goes wrong. In practice this only happens when userspace is
3302 * racing with itself.
3305 fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
3309 const struct filedescent *fde;
3311 const struct fdescenttbl *fdt;
3315 const cap_rights_t *haverights;
3318 fdt = fdp->fd_files;
3319 if (__predict_false((u_int)fd >= fdt->fdt_nfiles)) {
3324 seq = seqc_read_notmodify(fd_seqc(fdt, fd));
3325 fde = &fdt->fdt_ofiles[fd];
3326 haverights = cap_rights_fde_inline(fde);
3329 fp = fdt->fdt_ofiles[fd].fde_file;
3331 if (__predict_false(fp == NULL))
3334 if (__predict_false(cap_check_inline_transient(haverights, needrightsp)))
3337 if (__predict_false(!refcount_acquire_if_not_zero(&fp->f_count)))
3341 * Use an acquire barrier to force re-reading of fdt so it is
3342 * refreshed for verification.
3344 atomic_thread_fence_acq();
3345 fdt = fdp->fd_files;
3347 if (__predict_false(!seqc_consistent_nomb(fd_seqc(fdt, fd), seq)))
3349 if (__predict_false(fp != fdt->fdt_ofiles[fd].fde_file))
3355 fdrop(fp, curthread);
3358 return (fget_unlocked_seq(fdp, fd, needrightsp, fpp, NULL));
3362 * Translate fd -> file when the caller guarantees the file descriptor table
3363 * can't be changed by others.
3365 * Note this does not mean the file object itself is only visible to the caller,
3366 * merely that it wont disappear without having to be referenced.
3368 * Must be paired with fput_only_user.
3372 fget_only_user(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
3375 const struct filedescent *fde;
3376 const struct fdescenttbl *fdt;
3377 const cap_rights_t *haverights;
3381 MPASS(FILEDESC_IS_ONLY_USER(fdp));
3384 if (__predict_false(fd >= fdp->fd_nfiles))
3387 fdt = fdp->fd_files;
3388 fde = &fdt->fdt_ofiles[fd];
3390 if (__predict_false(fp == NULL))
3392 MPASS(refcount_load(&fp->f_count) > 0);
3393 haverights = cap_rights_fde_inline(fde);
3394 error = cap_check_inline(haverights, needrightsp);
3395 if (__predict_false(error != 0))
3402 fget_only_user(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
3407 MPASS(FILEDESC_IS_ONLY_USER(fdp));
3410 if (__predict_false(fd >= fdp->fd_nfiles))
3413 fp = fdp->fd_ofiles[fd].fde_file;
3414 if (__predict_false(fp == NULL))
3417 MPASS(refcount_load(&fp->f_count) > 0);
3424 * Extract the file pointer associated with the specified descriptor for the
3425 * current user process.
3427 * If the descriptor doesn't exist or doesn't match 'flags', EBADF is
3430 * File's rights will be checked against the capability rights mask.
3432 * If an error occurred the non-zero error is returned and *fpp is set to
3433 * NULL. Otherwise *fpp is held and set and zero is returned. Caller is
3434 * responsible for fdrop().
3437 _fget(struct thread *td, int fd, struct file **fpp, int flags,
3438 cap_rights_t *needrightsp)
3440 struct filedesc *fdp;
3445 fdp = td->td_proc->p_fd;
3446 error = fget_unlocked(fdp, fd, needrightsp, &fp);
3447 if (__predict_false(error != 0))
3449 if (__predict_false(fp->f_ops == &badfileops)) {
3455 * FREAD and FWRITE failure return EBADF as per POSIX.
3461 if ((fp->f_flag & flags) == 0)
3465 if (fp->f_ops != &path_fileops &&
3466 ((fp->f_flag & (FREAD | FEXEC)) == 0 ||
3467 (fp->f_flag & FWRITE) != 0))
3473 KASSERT(0, ("wrong flags"));
3486 fget(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
3489 return (_fget(td, fd, fpp, 0, rightsp));
3493 fget_mmap(struct thread *td, int fd, cap_rights_t *rightsp, vm_prot_t *maxprotp,
3497 #ifndef CAPABILITIES
3498 error = _fget(td, fd, fpp, 0, rightsp);
3499 if (maxprotp != NULL)
3500 *maxprotp = VM_PROT_ALL;
3503 cap_rights_t fdrights;
3504 struct filedesc *fdp;
3509 fdp = td->td_proc->p_fd;
3510 MPASS(cap_rights_is_set(rightsp, CAP_MMAP));
3512 error = fget_unlocked_seq(fdp, fd, rightsp, &fp, &seq);
3513 if (__predict_false(error != 0))
3515 if (__predict_false(fp->f_ops == &badfileops)) {
3519 if (maxprotp != NULL)
3520 fdrights = *cap_rights(fdp, fd);
3521 if (!fd_modified(fdp, fd, seq))
3527 * If requested, convert capability rights to access flags.
3529 if (maxprotp != NULL)
3530 *maxprotp = cap_rights_to_vmprot(&fdrights);
3537 fget_read(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
3540 return (_fget(td, fd, fpp, FREAD, rightsp));
3544 fget_write(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
3547 return (_fget(td, fd, fpp, FWRITE, rightsp));
3551 fget_fcntl(struct thread *td, int fd, cap_rights_t *rightsp, int needfcntl,
3554 struct filedesc *fdp = td->td_proc->p_fd;
3555 #ifndef CAPABILITIES
3556 return (fget_unlocked(fdp, fd, rightsp, fpp));
3563 MPASS(cap_rights_is_set(rightsp, CAP_FCNTL));
3565 error = fget_unlocked_seq(fdp, fd, rightsp, &fp, &seq);
3568 error = cap_fcntl_check(fdp, fd, needfcntl);
3569 if (!fd_modified(fdp, fd, seq))
3583 * Like fget() but loads the underlying vnode, or returns an error if the
3584 * descriptor does not represent a vnode. Note that pipes use vnodes but
3585 * never have VM objects. The returned vnode will be vref()'d.
3587 * XXX: what about the unused flags ?
3590 _fgetvp(struct thread *td, int fd, int flags, cap_rights_t *needrightsp,
3597 error = _fget(td, fd, &fp, flags, needrightsp);
3600 if (fp->f_vnode == NULL) {
3612 fgetvp(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
3615 return (_fgetvp(td, fd, 0, rightsp, vpp));
3619 fgetvp_rights(struct thread *td, int fd, cap_rights_t *needrightsp,
3620 struct filecaps *havecaps, struct vnode **vpp)
3622 struct filecaps caps;
3626 error = fget_cap(td, fd, needrightsp, &fp, &caps);
3629 if (fp->f_ops == &badfileops) {
3633 if (fp->f_vnode == NULL) {
3645 filecaps_free(&caps);
3651 fgetvp_read(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
3654 return (_fgetvp(td, fd, FREAD, rightsp, vpp));
3658 fgetvp_exec(struct thread *td, int fd, cap_rights_t *rightsp, struct vnode **vpp)
3661 return (_fgetvp(td, fd, FEXEC, rightsp, vpp));
3666 fgetvp_write(struct thread *td, int fd, cap_rights_t *rightsp,
3670 return (_fgetvp(td, fd, FWRITE, rightsp, vpp));
3675 * Handle the last reference to a file being closed.
3677 * Without the noinline attribute clang keeps inlining the func thorough this
3678 * file when fdrop is used.
3681 _fdrop(struct file *fp, struct thread *td)
3687 count = refcount_load(&fp->f_count);
3689 panic("fdrop: fp %p count %d", fp, count);
3691 error = fo_close(fp, td);
3692 atomic_subtract_int(&openfiles, 1);
3694 free(fp->f_advice, M_FADVISE);
3695 uma_zfree(file_zone, fp);
3701 * Apply an advisory lock on a file descriptor.
3703 * Just attempt to get a record lock of the requested type on the entire file
3704 * (l_whence = SEEK_SET, l_start = 0, l_len = 0).
3706 #ifndef _SYS_SYSPROTO_H_
3714 sys_flock(struct thread *td, struct flock_args *uap)
3721 error = fget(td, uap->fd, &cap_flock_rights, &fp);
3725 if (fp->f_type != DTYPE_VNODE && fp->f_type != DTYPE_FIFO) {
3728 if (fp->f_ops == &path_fileops) {
3734 lf.l_whence = SEEK_SET;
3737 if (uap->how & LOCK_UN) {
3738 lf.l_type = F_UNLCK;
3739 atomic_clear_int(&fp->f_flag, FHASLOCK);
3740 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK);
3743 if (uap->how & LOCK_EX)
3744 lf.l_type = F_WRLCK;
3745 else if (uap->how & LOCK_SH)
3746 lf.l_type = F_RDLCK;
3751 atomic_set_int(&fp->f_flag, FHASLOCK);
3752 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
3753 (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT);
3759 * Duplicate the specified descriptor to a free descriptor.
3762 dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode,
3763 int openerror, int *indxp)
3765 struct filedescent *newfde, *oldfde;
3770 KASSERT(openerror == ENODEV || openerror == ENXIO,
3771 ("unexpected error %d in %s", openerror, __func__));
3774 * If the to-be-dup'd fd number is greater than the allowed number
3775 * of file descriptors, or the fd to be dup'd has already been
3776 * closed, then reject.
3778 FILEDESC_XLOCK(fdp);
3779 if ((fp = fget_locked(fdp, dfd)) == NULL) {
3780 FILEDESC_XUNLOCK(fdp);
3784 error = fdalloc(td, 0, &indx);
3786 FILEDESC_XUNLOCK(fdp);
3791 * There are two cases of interest here.
3793 * For ENODEV simply dup (dfd) to file descriptor (indx) and return.
3795 * For ENXIO steal away the file structure from (dfd) and store it in
3796 * (indx). (dfd) is effectively closed by this operation.
3798 switch (openerror) {
3801 * Check that the mode the file is being opened for is a
3802 * subset of the mode of the existing descriptor.
3804 if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) {
3805 fdunused(fdp, indx);
3806 FILEDESC_XUNLOCK(fdp);
3810 fdunused(fdp, indx);
3811 FILEDESC_XUNLOCK(fdp);
3814 newfde = &fdp->fd_ofiles[indx];
3815 oldfde = &fdp->fd_ofiles[dfd];
3816 ioctls = filecaps_copy_prep(&oldfde->fde_caps);
3818 seqc_write_begin(&newfde->fde_seqc);
3820 memcpy(newfde, oldfde, fde_change_size);
3821 filecaps_copy_finish(&oldfde->fde_caps, &newfde->fde_caps,
3824 seqc_write_end(&newfde->fde_seqc);
3829 * Steal away the file pointer from dfd and stuff it into indx.
3831 newfde = &fdp->fd_ofiles[indx];
3832 oldfde = &fdp->fd_ofiles[dfd];
3834 seqc_write_begin(&newfde->fde_seqc);
3836 memcpy(newfde, oldfde, fde_change_size);
3837 oldfde->fde_file = NULL;
3840 seqc_write_end(&newfde->fde_seqc);
3844 FILEDESC_XUNLOCK(fdp);
3850 * This sysctl determines if we will allow a process to chroot(2) if it
3851 * has a directory open:
3852 * 0: disallowed for all processes.
3853 * 1: allowed for processes that were not already chroot(2)'ed.
3854 * 2: allowed for all processes.
3857 static int chroot_allow_open_directories = 1;
3859 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW,
3860 &chroot_allow_open_directories, 0,
3861 "Allow a process to chroot(2) if it has a directory open");
3864 * Helper function for raised chroot(2) security function: Refuse if
3865 * any filedescriptors are open directories.
3868 chroot_refuse_vdir_fds(struct filedesc *fdp)
3874 FILEDESC_LOCK_ASSERT(fdp);
3876 lastfile = fdlastfile(fdp);
3877 for (fd = 0; fd <= lastfile; fd++) {
3878 fp = fget_locked(fdp, fd);
3881 if (fp->f_type == DTYPE_VNODE) {
3883 if (vp->v_type == VDIR)
3891 pwd_fill(struct pwd *oldpwd, struct pwd *newpwd)
3894 if (newpwd->pwd_cdir == NULL && oldpwd->pwd_cdir != NULL) {
3895 vrefact(oldpwd->pwd_cdir);
3896 newpwd->pwd_cdir = oldpwd->pwd_cdir;
3899 if (newpwd->pwd_rdir == NULL && oldpwd->pwd_rdir != NULL) {
3900 vrefact(oldpwd->pwd_rdir);
3901 newpwd->pwd_rdir = oldpwd->pwd_rdir;
3904 if (newpwd->pwd_jdir == NULL && oldpwd->pwd_jdir != NULL) {
3905 vrefact(oldpwd->pwd_jdir);
3906 newpwd->pwd_jdir = oldpwd->pwd_jdir;
3911 pwd_hold_pwddesc(struct pwddesc *pdp)
3915 PWDDESC_ASSERT_XLOCKED(pdp);
3916 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
3918 refcount_acquire(&pwd->pwd_refcount);
3923 pwd_hold_smr(struct pwd *pwd)
3927 if (__predict_true(refcount_acquire_if_not_zero(&pwd->pwd_refcount))) {
3934 pwd_hold(struct thread *td)
3936 struct pwddesc *pdp;
3939 pdp = td->td_proc->p_pd;
3942 pwd = vfs_smr_entered_load(&pdp->pd_pwd);
3943 if (pwd_hold_smr(pwd)) {
3949 pwd = pwd_hold_pwddesc(pdp);
3951 PWDDESC_XUNLOCK(pdp);
3956 pwd_hold_proc(struct proc *p)
3958 struct pwddesc *pdp;
3961 PROC_ASSERT_HELD(p);
3968 pwd = pwd_hold_pwddesc(pdp);
3970 PWDDESC_XUNLOCK(pdp);
3980 pwd = uma_zalloc_smr(pwd_zone, M_WAITOK);
3981 bzero(pwd, sizeof(*pwd));
3982 refcount_init(&pwd->pwd_refcount, 1);
3987 pwd_drop(struct pwd *pwd)
3990 if (!refcount_release(&pwd->pwd_refcount))
3993 if (pwd->pwd_cdir != NULL)
3994 vrele(pwd->pwd_cdir);
3995 if (pwd->pwd_rdir != NULL)
3996 vrele(pwd->pwd_rdir);
3997 if (pwd->pwd_jdir != NULL)
3998 vrele(pwd->pwd_jdir);
3999 uma_zfree_smr(pwd_zone, pwd);
4003 * The caller is responsible for invoking priv_check() and
4004 * mac_vnode_check_chroot() to authorize this operation.
4007 pwd_chroot(struct thread *td, struct vnode *vp)
4009 struct pwddesc *pdp;
4010 struct filedesc *fdp;
4011 struct pwd *newpwd, *oldpwd;
4014 fdp = td->td_proc->p_fd;
4015 pdp = td->td_proc->p_pd;
4016 newpwd = pwd_alloc();
4017 FILEDESC_SLOCK(fdp);
4019 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4020 if (chroot_allow_open_directories == 0 ||
4021 (chroot_allow_open_directories == 1 &&
4022 oldpwd->pwd_rdir != rootvnode)) {
4023 error = chroot_refuse_vdir_fds(fdp);
4024 FILEDESC_SUNLOCK(fdp);
4026 PWDDESC_XUNLOCK(pdp);
4031 FILEDESC_SUNLOCK(fdp);
4035 newpwd->pwd_rdir = vp;
4036 if (oldpwd->pwd_jdir == NULL) {
4038 newpwd->pwd_jdir = vp;
4040 pwd_fill(oldpwd, newpwd);
4041 pwd_set(pdp, newpwd);
4042 PWDDESC_XUNLOCK(pdp);
4048 pwd_chdir(struct thread *td, struct vnode *vp)
4050 struct pwddesc *pdp;
4051 struct pwd *newpwd, *oldpwd;
4053 VNPASS(vp->v_usecount > 0, vp);
4055 newpwd = pwd_alloc();
4056 pdp = td->td_proc->p_pd;
4058 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4059 newpwd->pwd_cdir = vp;
4060 pwd_fill(oldpwd, newpwd);
4061 pwd_set(pdp, newpwd);
4062 PWDDESC_XUNLOCK(pdp);
4067 * jail_attach(2) changes both root and working directories.
4070 pwd_chroot_chdir(struct thread *td, struct vnode *vp)
4072 struct pwddesc *pdp;
4073 struct filedesc *fdp;
4074 struct pwd *newpwd, *oldpwd;
4077 fdp = td->td_proc->p_fd;
4078 pdp = td->td_proc->p_pd;
4079 newpwd = pwd_alloc();
4080 FILEDESC_SLOCK(fdp);
4082 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4083 error = chroot_refuse_vdir_fds(fdp);
4084 FILEDESC_SUNLOCK(fdp);
4086 PWDDESC_XUNLOCK(pdp);
4092 newpwd->pwd_rdir = vp;
4094 newpwd->pwd_cdir = vp;
4095 if (oldpwd->pwd_jdir == NULL) {
4097 newpwd->pwd_jdir = vp;
4099 pwd_fill(oldpwd, newpwd);
4100 pwd_set(pdp, newpwd);
4101 PWDDESC_XUNLOCK(pdp);
4107 pwd_ensure_dirs(void)
4109 struct pwddesc *pdp;
4110 struct pwd *oldpwd, *newpwd;
4112 pdp = curproc->p_pd;
4114 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4115 if (oldpwd->pwd_cdir != NULL && oldpwd->pwd_rdir != NULL) {
4116 PWDDESC_XUNLOCK(pdp);
4119 PWDDESC_XUNLOCK(pdp);
4121 newpwd = pwd_alloc();
4123 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4124 pwd_fill(oldpwd, newpwd);
4125 if (newpwd->pwd_cdir == NULL) {
4127 newpwd->pwd_cdir = rootvnode;
4129 if (newpwd->pwd_rdir == NULL) {
4131 newpwd->pwd_rdir = rootvnode;
4133 pwd_set(pdp, newpwd);
4134 PWDDESC_XUNLOCK(pdp);
4139 pwd_set_rootvnode(void)
4141 struct pwddesc *pdp;
4142 struct pwd *oldpwd, *newpwd;
4144 pdp = curproc->p_pd;
4146 newpwd = pwd_alloc();
4148 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4150 newpwd->pwd_cdir = rootvnode;
4152 newpwd->pwd_rdir = rootvnode;
4153 pwd_fill(oldpwd, newpwd);
4154 pwd_set(pdp, newpwd);
4155 PWDDESC_XUNLOCK(pdp);
4160 * Scan all active processes and prisons to see if any of them have a current
4161 * or root directory of `olddp'. If so, replace them with the new mount point.
4164 mountcheckdirs(struct vnode *olddp, struct vnode *newdp)
4166 struct pwddesc *pdp;
4167 struct pwd *newpwd, *oldpwd;
4172 if (vrefcnt(olddp) == 1)
4175 newpwd = pwd_alloc();
4176 sx_slock(&allproc_lock);
4177 FOREACH_PROC_IN_SYSTEM(p) {
4184 oldpwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4185 if (oldpwd == NULL ||
4186 (oldpwd->pwd_cdir != olddp &&
4187 oldpwd->pwd_rdir != olddp &&
4188 oldpwd->pwd_jdir != olddp)) {
4189 PWDDESC_XUNLOCK(pdp);
4193 if (oldpwd->pwd_cdir == olddp) {
4195 newpwd->pwd_cdir = newdp;
4197 if (oldpwd->pwd_rdir == olddp) {
4199 newpwd->pwd_rdir = newdp;
4201 if (oldpwd->pwd_jdir == olddp) {
4203 newpwd->pwd_jdir = newdp;
4205 pwd_fill(oldpwd, newpwd);
4206 pwd_set(pdp, newpwd);
4207 PWDDESC_XUNLOCK(pdp);
4210 newpwd = pwd_alloc();
4212 sx_sunlock(&allproc_lock);
4214 if (rootvnode == olddp) {
4219 mtx_lock(&prison0.pr_mtx);
4220 if (prison0.pr_root == olddp) {
4222 prison0.pr_root = newdp;
4225 mtx_unlock(&prison0.pr_mtx);
4226 sx_slock(&allprison_lock);
4227 TAILQ_FOREACH(pr, &allprison, pr_list) {
4228 mtx_lock(&pr->pr_mtx);
4229 if (pr->pr_root == olddp) {
4231 pr->pr_root = newdp;
4234 mtx_unlock(&pr->pr_mtx);
4236 sx_sunlock(&allprison_lock);
4241 struct filedesc_to_leader *
4242 filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader)
4244 struct filedesc_to_leader *fdtol;
4246 fdtol = malloc(sizeof(struct filedesc_to_leader),
4247 M_FILEDESC_TO_LEADER, M_WAITOK);
4248 fdtol->fdl_refcount = 1;
4249 fdtol->fdl_holdcount = 0;
4250 fdtol->fdl_wakeup = 0;
4251 fdtol->fdl_leader = leader;
4253 FILEDESC_XLOCK(fdp);
4254 fdtol->fdl_next = old->fdl_next;
4255 fdtol->fdl_prev = old;
4256 old->fdl_next = fdtol;
4257 fdtol->fdl_next->fdl_prev = fdtol;
4258 FILEDESC_XUNLOCK(fdp);
4260 fdtol->fdl_next = fdtol;
4261 fdtol->fdl_prev = fdtol;
4267 sysctl_kern_proc_nfds(SYSCTL_HANDLER_ARGS)
4270 struct filedesc *fdp;
4272 int count, off, minoff;
4278 if (*(int *)arg1 != 0)
4281 fdp = curproc->p_fd;
4283 FILEDESC_SLOCK(fdp);
4285 off = NDSLOT(fdp->fd_nfiles - 1);
4286 for (minoff = NDSLOT(0); off >= minoff; --off)
4287 count += bitcountl(map[off]);
4288 FILEDESC_SUNLOCK(fdp);
4290 return (SYSCTL_OUT(req, &count, sizeof(count)));
4293 static SYSCTL_NODE(_kern_proc, KERN_PROC_NFDS, nfds,
4294 CTLFLAG_RD|CTLFLAG_CAPRD|CTLFLAG_MPSAFE, sysctl_kern_proc_nfds,
4295 "Number of open file descriptors");
4298 * Get file structures globally.
4301 sysctl_kern_file(SYSCTL_HANDLER_ARGS)
4304 struct filedesc *fdp;
4307 int error, n, lastfile;
4309 error = sysctl_wire_old_buffer(req, 0);
4312 if (req->oldptr == NULL) {
4314 sx_slock(&allproc_lock);
4315 FOREACH_PROC_IN_SYSTEM(p) {
4317 if (p->p_state == PRS_NEW) {
4325 /* overestimates sparse tables. */
4326 n += fdp->fd_nfiles;
4329 sx_sunlock(&allproc_lock);
4330 return (SYSCTL_OUT(req, 0, n * sizeof(xf)));
4333 bzero(&xf, sizeof(xf));
4334 xf.xf_size = sizeof(xf);
4335 sx_slock(&allproc_lock);
4336 FOREACH_PROC_IN_SYSTEM(p) {
4338 if (p->p_state == PRS_NEW) {
4342 if (p_cansee(req->td, p) != 0) {
4346 xf.xf_pid = p->p_pid;
4347 xf.xf_uid = p->p_ucred->cr_uid;
4352 FILEDESC_SLOCK(fdp);
4353 if (refcount_load(&fdp->fd_refcnt) == 0)
4355 lastfile = fdlastfile(fdp);
4356 for (n = 0; refcount_load(&fdp->fd_refcnt) > 0 && n <= lastfile;
4358 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL)
4361 xf.xf_file = (uintptr_t)fp;
4362 xf.xf_data = (uintptr_t)fp->f_data;
4363 xf.xf_vnode = (uintptr_t)fp->f_vnode;
4364 xf.xf_type = (uintptr_t)fp->f_type;
4365 xf.xf_count = refcount_load(&fp->f_count);
4367 xf.xf_offset = foffset_get(fp);
4368 xf.xf_flag = fp->f_flag;
4369 error = SYSCTL_OUT(req, &xf, sizeof(xf));
4372 * There is no need to re-check the fdtable refcount
4373 * here since the filedesc lock is not dropped in the
4380 FILEDESC_SUNLOCK(fdp);
4385 sx_sunlock(&allproc_lock);
4389 SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
4390 0, 0, sysctl_kern_file, "S,xfile", "Entire file table");
4392 #ifdef KINFO_FILE_SIZE
4393 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE);
4397 xlate_fflags(int fflags)
4399 static const struct {
4402 } fflags_table[] = {
4403 { FAPPEND, KF_FLAG_APPEND },
4404 { FASYNC, KF_FLAG_ASYNC },
4405 { FFSYNC, KF_FLAG_FSYNC },
4406 { FHASLOCK, KF_FLAG_HASLOCK },
4407 { FNONBLOCK, KF_FLAG_NONBLOCK },
4408 { FREAD, KF_FLAG_READ },
4409 { FWRITE, KF_FLAG_WRITE },
4410 { O_CREAT, KF_FLAG_CREAT },
4411 { O_DIRECT, KF_FLAG_DIRECT },
4412 { O_EXCL, KF_FLAG_EXCL },
4413 { O_EXEC, KF_FLAG_EXEC },
4414 { O_EXLOCK, KF_FLAG_EXLOCK },
4415 { O_NOFOLLOW, KF_FLAG_NOFOLLOW },
4416 { O_SHLOCK, KF_FLAG_SHLOCK },
4417 { O_TRUNC, KF_FLAG_TRUNC }
4423 for (i = 0; i < nitems(fflags_table); i++)
4424 if (fflags & fflags_table[i].fflag)
4425 kflags |= fflags_table[i].kf_fflag;
4429 /* Trim unused data from kf_path by truncating the structure size. */
4431 pack_kinfo(struct kinfo_file *kif)
4434 kif->kf_structsize = offsetof(struct kinfo_file, kf_path) +
4435 strlen(kif->kf_path) + 1;
4436 kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t));
4440 export_file_to_kinfo(struct file *fp, int fd, cap_rights_t *rightsp,
4441 struct kinfo_file *kif, struct filedesc *fdp, int flags)
4445 bzero(kif, sizeof(*kif));
4447 /* Set a default type to allow for empty fill_kinfo() methods. */
4448 kif->kf_type = KF_TYPE_UNKNOWN;
4449 kif->kf_flags = xlate_fflags(fp->f_flag);
4450 if (rightsp != NULL)
4451 kif->kf_cap_rights = *rightsp;
4453 cap_rights_init_zero(&kif->kf_cap_rights);
4455 kif->kf_ref_count = refcount_load(&fp->f_count);
4456 kif->kf_offset = foffset_get(fp);
4459 * This may drop the filedesc lock, so the 'fp' cannot be
4460 * accessed after this call.
4462 error = fo_fill_kinfo(fp, kif, fdp);
4464 kif->kf_status |= KF_ATTR_VALID;
4465 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0)
4468 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t));
4472 export_vnode_to_kinfo(struct vnode *vp, int fd, int fflags,
4473 struct kinfo_file *kif, int flags)
4477 bzero(kif, sizeof(*kif));
4479 kif->kf_type = KF_TYPE_VNODE;
4480 error = vn_fill_kinfo_vnode(vp, kif);
4482 kif->kf_status |= KF_ATTR_VALID;
4483 kif->kf_flags = xlate_fflags(fflags);
4484 cap_rights_init_zero(&kif->kf_cap_rights);
4486 kif->kf_ref_count = -1;
4487 kif->kf_offset = -1;
4488 if ((flags & KERN_FILEDESC_PACK_KINFO) != 0)
4491 kif->kf_structsize = roundup2(sizeof(*kif), sizeof(uint64_t));
4495 struct export_fd_buf {
4496 struct filedesc *fdp;
4497 struct pwddesc *pdp;
4500 struct kinfo_file kif;
4505 export_kinfo_to_sb(struct export_fd_buf *efbuf)
4507 struct kinfo_file *kif;
4510 if (efbuf->remainder != -1) {
4511 if (efbuf->remainder < kif->kf_structsize)
4513 efbuf->remainder -= kif->kf_structsize;
4515 if (sbuf_bcat(efbuf->sb, kif, kif->kf_structsize) != 0)
4516 return (sbuf_error(efbuf->sb));
4521 export_file_to_sb(struct file *fp, int fd, cap_rights_t *rightsp,
4522 struct export_fd_buf *efbuf)
4526 if (efbuf->remainder == 0)
4528 export_file_to_kinfo(fp, fd, rightsp, &efbuf->kif, efbuf->fdp,
4530 FILEDESC_SUNLOCK(efbuf->fdp);
4531 error = export_kinfo_to_sb(efbuf);
4532 FILEDESC_SLOCK(efbuf->fdp);
4537 export_vnode_to_sb(struct vnode *vp, int fd, int fflags,
4538 struct export_fd_buf *efbuf)
4542 if (efbuf->remainder == 0)
4544 if (efbuf->pdp != NULL)
4545 PWDDESC_XUNLOCK(efbuf->pdp);
4546 export_vnode_to_kinfo(vp, fd, fflags, &efbuf->kif, efbuf->flags);
4547 error = export_kinfo_to_sb(efbuf);
4548 if (efbuf->pdp != NULL)
4549 PWDDESC_XLOCK(efbuf->pdp);
4554 * Store a process file descriptor information to sbuf.
4556 * Takes a locked proc as argument, and returns with the proc unlocked.
4559 kern_proc_filedesc_out(struct proc *p, struct sbuf *sb, ssize_t maxlen,
4563 struct filedesc *fdp;
4564 struct pwddesc *pdp;
4565 struct export_fd_buf *efbuf;
4566 struct vnode *cttyvp, *textvp, *tracevp;
4568 int error, i, lastfile;
4569 cap_rights_t rights;
4571 PROC_LOCK_ASSERT(p, MA_OWNED);
4574 tracevp = ktr_get_tracevp(p, true);
4576 textvp = p->p_textvp;
4579 /* Controlling tty. */
4581 if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) {
4582 cttyvp = p->p_pgrp->pg_session->s_ttyvp;
4590 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK);
4594 efbuf->remainder = maxlen;
4595 efbuf->flags = flags;
4598 if (tracevp != NULL)
4599 error = export_vnode_to_sb(tracevp, KF_FD_TYPE_TRACE,
4600 FREAD | FWRITE, efbuf);
4601 if (error == 0 && textvp != NULL)
4602 error = export_vnode_to_sb(textvp, KF_FD_TYPE_TEXT, FREAD,
4604 if (error == 0 && cttyvp != NULL)
4605 error = export_vnode_to_sb(cttyvp, KF_FD_TYPE_CTTY,
4606 FREAD | FWRITE, efbuf);
4607 if (error != 0 || pdp == NULL || fdp == NULL)
4612 pwd = pwd_hold_pwddesc(pdp);
4614 /* working directory */
4615 if (pwd->pwd_cdir != NULL) {
4616 vrefact(pwd->pwd_cdir);
4617 error = export_vnode_to_sb(pwd->pwd_cdir,
4618 KF_FD_TYPE_CWD, FREAD, efbuf);
4620 /* root directory */
4621 if (error == 0 && pwd->pwd_rdir != NULL) {
4622 vrefact(pwd->pwd_rdir);
4623 error = export_vnode_to_sb(pwd->pwd_rdir,
4624 KF_FD_TYPE_ROOT, FREAD, efbuf);
4626 /* jail directory */
4627 if (error == 0 && pwd->pwd_jdir != NULL) {
4628 vrefact(pwd->pwd_jdir);
4629 error = export_vnode_to_sb(pwd->pwd_jdir,
4630 KF_FD_TYPE_JAIL, FREAD, efbuf);
4633 PWDDESC_XUNLOCK(pdp);
4638 FILEDESC_SLOCK(fdp);
4639 if (refcount_load(&fdp->fd_refcnt) == 0)
4641 lastfile = fdlastfile(fdp);
4642 for (i = 0; i <= lastfile; i++) {
4643 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL)
4646 rights = *cap_rights(fdp, i);
4647 #else /* !CAPABILITIES */
4648 rights = cap_no_rights;
4651 * Create sysctl entry. It is OK to drop the filedesc
4652 * lock inside of export_file_to_sb() as we will
4653 * re-validate and re-evaluate its properties when the
4656 error = export_file_to_sb(fp, i, &rights, efbuf);
4657 if (error != 0 || refcount_load(&fdp->fd_refcnt) == 0)
4661 FILEDESC_SUNLOCK(fdp);
4667 free(efbuf, M_TEMP);
4671 #define FILEDESC_SBUF_SIZE (sizeof(struct kinfo_file) * 5)
4674 * Get per-process file descriptors for use by procstat(1), et al.
4677 sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS)
4683 int error, error2, *name;
4691 sbuf_new_for_sysctl(&sb, NULL, FILEDESC_SBUF_SIZE, req);
4692 sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
4693 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p);
4698 maxlen = req->oldptr != NULL ? req->oldlen : -1;
4699 error = kern_proc_filedesc_out(p, &sb, maxlen,
4700 KERN_FILEDESC_PACK_KINFO);
4701 error2 = sbuf_finish(&sb);
4703 return (error != 0 ? error : error2);
4706 #ifdef COMPAT_FREEBSD7
4707 #ifdef KINFO_OFILE_SIZE
4708 CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE);
4712 kinfo_to_okinfo(struct kinfo_file *kif, struct kinfo_ofile *okif)
4715 okif->kf_structsize = sizeof(*okif);
4716 okif->kf_type = kif->kf_type;
4717 okif->kf_fd = kif->kf_fd;
4718 okif->kf_ref_count = kif->kf_ref_count;
4719 okif->kf_flags = kif->kf_flags & (KF_FLAG_READ | KF_FLAG_WRITE |
4720 KF_FLAG_APPEND | KF_FLAG_ASYNC | KF_FLAG_FSYNC | KF_FLAG_NONBLOCK |
4721 KF_FLAG_DIRECT | KF_FLAG_HASLOCK);
4722 okif->kf_offset = kif->kf_offset;
4723 if (kif->kf_type == KF_TYPE_VNODE)
4724 okif->kf_vnode_type = kif->kf_un.kf_file.kf_file_type;
4726 okif->kf_vnode_type = KF_VTYPE_VNON;
4727 strlcpy(okif->kf_path, kif->kf_path, sizeof(okif->kf_path));
4728 if (kif->kf_type == KF_TYPE_SOCKET) {
4729 okif->kf_sock_domain = kif->kf_un.kf_sock.kf_sock_domain0;
4730 okif->kf_sock_type = kif->kf_un.kf_sock.kf_sock_type0;
4731 okif->kf_sock_protocol = kif->kf_un.kf_sock.kf_sock_protocol0;
4732 okif->kf_sa_local = kif->kf_un.kf_sock.kf_sa_local;
4733 okif->kf_sa_peer = kif->kf_un.kf_sock.kf_sa_peer;
4735 okif->kf_sa_local.ss_family = AF_UNSPEC;
4736 okif->kf_sa_peer.ss_family = AF_UNSPEC;
4741 export_vnode_for_osysctl(struct vnode *vp, int type, struct kinfo_file *kif,
4742 struct kinfo_ofile *okif, struct pwddesc *pdp, struct sysctl_req *req)
4747 PWDDESC_XUNLOCK(pdp);
4748 export_vnode_to_kinfo(vp, type, 0, kif, KERN_FILEDESC_PACK_KINFO);
4749 kinfo_to_okinfo(kif, okif);
4750 error = SYSCTL_OUT(req, okif, sizeof(*okif));
4756 * Get per-process file descriptors for use by procstat(1), et al.
4759 sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS)
4761 struct kinfo_ofile *okif;
4762 struct kinfo_file *kif;
4763 struct filedesc *fdp;
4764 struct pwddesc *pdp;
4767 int error, i, lastfile, *name;
4776 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p);
4783 if (fdp == NULL || pdp == NULL) {
4788 kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK);
4789 okif = malloc(sizeof(*okif), M_TEMP, M_WAITOK);
4791 pwd = pwd_hold_pwddesc(pdp);
4793 if (pwd->pwd_cdir != NULL)
4794 export_vnode_for_osysctl(pwd->pwd_cdir, KF_FD_TYPE_CWD, kif,
4796 if (pwd->pwd_rdir != NULL)
4797 export_vnode_for_osysctl(pwd->pwd_rdir, KF_FD_TYPE_ROOT, kif,
4799 if (pwd->pwd_jdir != NULL)
4800 export_vnode_for_osysctl(pwd->pwd_jdir, KF_FD_TYPE_JAIL, kif,
4803 PWDDESC_XUNLOCK(pdp);
4806 FILEDESC_SLOCK(fdp);
4807 if (refcount_load(&fdp->fd_refcnt) == 0)
4809 lastfile = fdlastfile(fdp);
4810 for (i = 0; i <= lastfile; i++) {
4811 if ((fp = fdp->fd_ofiles[i].fde_file) == NULL)
4813 export_file_to_kinfo(fp, i, NULL, kif, fdp,
4814 KERN_FILEDESC_PACK_KINFO);
4815 FILEDESC_SUNLOCK(fdp);
4816 kinfo_to_okinfo(kif, okif);
4817 error = SYSCTL_OUT(req, okif, sizeof(*okif));
4818 FILEDESC_SLOCK(fdp);
4819 if (error != 0 || refcount_load(&fdp->fd_refcnt) == 0)
4823 FILEDESC_SUNLOCK(fdp);
4831 static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc,
4832 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_ofiledesc,
4833 "Process ofiledesc entries");
4834 #endif /* COMPAT_FREEBSD7 */
4837 vntype_to_kinfo(int vtype)
4842 } vtypes_table[] = {
4843 { VBAD, KF_VTYPE_VBAD },
4844 { VBLK, KF_VTYPE_VBLK },
4845 { VCHR, KF_VTYPE_VCHR },
4846 { VDIR, KF_VTYPE_VDIR },
4847 { VFIFO, KF_VTYPE_VFIFO },
4848 { VLNK, KF_VTYPE_VLNK },
4849 { VNON, KF_VTYPE_VNON },
4850 { VREG, KF_VTYPE_VREG },
4851 { VSOCK, KF_VTYPE_VSOCK }
4856 * Perform vtype translation.
4858 for (i = 0; i < nitems(vtypes_table); i++)
4859 if (vtypes_table[i].vtype == vtype)
4860 return (vtypes_table[i].kf_vtype);
4862 return (KF_VTYPE_UNKNOWN);
4865 static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc,
4866 CTLFLAG_RD|CTLFLAG_MPSAFE, sysctl_kern_proc_filedesc,
4867 "Process filedesc entries");
4870 * Store a process current working directory information to sbuf.
4872 * Takes a locked proc as argument, and returns with the proc unlocked.
4875 kern_proc_cwd_out(struct proc *p, struct sbuf *sb, ssize_t maxlen)
4877 struct pwddesc *pdp;
4879 struct export_fd_buf *efbuf;
4883 PROC_LOCK_ASSERT(p, MA_OWNED);
4890 efbuf = malloc(sizeof(*efbuf), M_TEMP, M_WAITOK);
4894 efbuf->remainder = maxlen;
4898 pwd = PWDDESC_XLOCKED_LOAD_PWD(pdp);
4899 cdir = pwd->pwd_cdir;
4904 error = export_vnode_to_sb(cdir, KF_FD_TYPE_CWD, FREAD, efbuf);
4906 PWDDESC_XUNLOCK(pdp);
4908 free(efbuf, M_TEMP);
4913 * Get per-process current working directory.
4916 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS)
4922 int error, error2, *name;
4930 sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file), req);
4931 sbuf_clear_flags(&sb, SBUF_INCLUDENUL);
4932 error = pget((pid_t)name[0], PGET_CANDEBUG | PGET_NOTWEXIT, &p);
4937 maxlen = req->oldptr != NULL ? req->oldlen : -1;
4938 error = kern_proc_cwd_out(p, &sb, maxlen);
4939 error2 = sbuf_finish(&sb);
4941 return (error != 0 ? error : error2);
4944 static SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD|CTLFLAG_MPSAFE,
4945 sysctl_kern_proc_cwd, "Process current working directory");
4949 * For the purposes of debugging, generate a human-readable string for the
4953 file_type_to_name(short type)
4981 case DTYPE_PROCDESC:
4985 case DTYPE_LINUXTFD:
4993 * For the purposes of debugging, identify a process (if any, perhaps one of
4994 * many) that references the passed file in its file descriptor array. Return
4997 static struct proc *
4998 file_to_first_proc(struct file *fp)
5000 struct filedesc *fdp;
5004 FOREACH_PROC_IN_SYSTEM(p) {
5005 if (p->p_state == PRS_NEW)
5010 for (n = 0; n < fdp->fd_nfiles; n++) {
5011 if (fp == fdp->fd_ofiles[n].fde_file)
5019 db_print_file(struct file *fp, int header)
5021 #define XPTRWIDTH ((int)howmany(sizeof(void *) * NBBY, 4))
5025 db_printf("%*s %6s %*s %8s %4s %5s %6s %*s %5s %s\n",
5026 XPTRWIDTH, "File", "Type", XPTRWIDTH, "Data", "Flag",
5027 "GCFl", "Count", "MCount", XPTRWIDTH, "Vnode", "FPID",
5029 p = file_to_first_proc(fp);
5030 db_printf("%*p %6s %*p %08x %04x %5d %6d %*p %5d %s\n", XPTRWIDTH,
5031 fp, file_type_to_name(fp->f_type), XPTRWIDTH, fp->f_data,
5032 fp->f_flag, 0, refcount_load(&fp->f_count), 0, XPTRWIDTH, fp->f_vnode,
5033 p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-");
5038 DB_SHOW_COMMAND(file, db_show_file)
5043 db_printf("usage: show file <addr>\n");
5046 fp = (struct file *)addr;
5047 db_print_file(fp, 1);
5050 DB_SHOW_COMMAND(files, db_show_files)
5052 struct filedesc *fdp;
5059 FOREACH_PROC_IN_SYSTEM(p) {
5060 if (p->p_state == PRS_NEW)
5062 if ((fdp = p->p_fd) == NULL)
5064 for (n = 0; n < fdp->fd_nfiles; ++n) {
5065 if ((fp = fdp->fd_ofiles[n].fde_file) == NULL)
5067 db_print_file(fp, header);
5074 SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW,
5075 &maxfilesperproc, 0, "Maximum files allowed open per process");
5077 SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW,
5078 &maxfiles, 0, "Maximum number of files");
5080 SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD,
5081 &openfiles, 0, "System-wide number of open files");
5085 filelistinit(void *dummy)
5088 file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL,
5089 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
5090 filedesc0_zone = uma_zcreate("filedesc0", sizeof(struct filedesc0),
5091 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
5092 pwd_zone = uma_zcreate("PWD", sizeof(struct pwd), NULL, NULL,
5093 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_SMR);
5095 * XXXMJG this is a temporary hack due to boot ordering issues against
5098 vfs_smr = uma_zone_get_smr(pwd_zone);
5099 mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF);
5101 SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL);
5103 /*-------------------------------------------------------------------*/
5106 badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred,
5107 int flags, struct thread *td)
5114 badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
5122 badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
5130 badfo_poll(struct file *fp, int events, struct ucred *active_cred,
5138 badfo_kqfilter(struct file *fp, struct knote *kn)
5145 badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred,
5153 badfo_close(struct file *fp, struct thread *td)
5160 badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
5168 badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
5176 badfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
5177 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
5185 badfo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
5191 struct fileops badfileops = {
5192 .fo_read = badfo_readwrite,
5193 .fo_write = badfo_readwrite,
5194 .fo_truncate = badfo_truncate,
5195 .fo_ioctl = badfo_ioctl,
5196 .fo_poll = badfo_poll,
5197 .fo_kqfilter = badfo_kqfilter,
5198 .fo_stat = badfo_stat,
5199 .fo_close = badfo_close,
5200 .fo_chmod = badfo_chmod,
5201 .fo_chown = badfo_chown,
5202 .fo_sendfile = badfo_sendfile,
5203 .fo_fill_kinfo = badfo_fill_kinfo,
5207 path_poll(struct file *fp, int events, struct ucred *active_cred,
5214 path_close(struct file *fp, struct thread *td)
5216 MPASS(fp->f_type == DTYPE_VNODE);
5217 fp->f_ops = &badfileops;
5222 struct fileops path_fileops = {
5223 .fo_read = badfo_readwrite,
5224 .fo_write = badfo_readwrite,
5225 .fo_truncate = badfo_truncate,
5226 .fo_ioctl = badfo_ioctl,
5227 .fo_poll = path_poll,
5228 .fo_kqfilter = vn_kqfilter_opath,
5229 .fo_stat = vn_statfile,
5230 .fo_close = path_close,
5231 .fo_chmod = badfo_chmod,
5232 .fo_chown = badfo_chown,
5233 .fo_sendfile = badfo_sendfile,
5234 .fo_fill_kinfo = vn_fill_kinfo,
5235 .fo_flags = DFLAG_PASSABLE,
5239 invfo_rdwr(struct file *fp, struct uio *uio, struct ucred *active_cred,
5240 int flags, struct thread *td)
5243 return (EOPNOTSUPP);
5247 invfo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
5255 invfo_ioctl(struct file *fp, u_long com, void *data,
5256 struct ucred *active_cred, struct thread *td)
5263 invfo_poll(struct file *fp, int events, struct ucred *active_cred,
5267 return (poll_no_poll(events));
5271 invfo_kqfilter(struct file *fp, struct knote *kn)
5278 invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
5286 invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
5294 invfo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
5295 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
5302 /*-------------------------------------------------------------------*/
5305 * File Descriptor pseudo-device driver (/dev/fd/).
5307 * Opening minor device N dup()s the file (if any) connected to file
5308 * descriptor N belonging to the calling process. Note that this driver
5309 * consists of only the ``open()'' routine, because all subsequent
5310 * references to this file will be direct to the other driver.
5312 * XXX: we could give this one a cloning event handler if necessary.
5317 fdopen(struct cdev *dev, int mode, int type, struct thread *td)
5321 * XXX Kludge: set curthread->td_dupfd to contain the value of the
5322 * the file descriptor being sought for duplication. The error
5323 * return ensures that the vnode for this device will be released
5324 * by vn_open. Open will detect this special error and take the
5325 * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN
5326 * will simply report the error.
5328 td->td_dupfd = dev2unit(dev);
5332 static struct cdevsw fildesc_cdevsw = {
5333 .d_version = D_VERSION,
5339 fildesc_drvinit(void *unused)
5343 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL,
5344 UID_ROOT, GID_WHEEL, 0666, "fd/0");
5345 make_dev_alias(dev, "stdin");
5346 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL,
5347 UID_ROOT, GID_WHEEL, 0666, "fd/1");
5348 make_dev_alias(dev, "stdout");
5349 dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL,
5350 UID_ROOT, GID_WHEEL, 0666, "fd/2");
5351 make_dev_alias(dev, "stderr");
5354 SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL);