xref: /freebsd-12.1/sys/kern/vfs_syscalls.c (revision 4bd91f6e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)vfs_syscalls.c	8.13 (Berkeley) 4/15/94
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include "opt_capsicum.h"
43 #include "opt_ktrace.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/bio.h>
48 #include <sys/buf.h>
49 #include <sys/capsicum.h>
50 #include <sys/disk.h>
51 #include <sys/sysent.h>
52 #include <sys/malloc.h>
53 #include <sys/mount.h>
54 #include <sys/mutex.h>
55 #include <sys/sysproto.h>
56 #include <sys/namei.h>
57 #include <sys/filedesc.h>
58 #include <sys/kernel.h>
59 #include <sys/fcntl.h>
60 #include <sys/file.h>
61 #include <sys/filio.h>
62 #include <sys/limits.h>
63 #include <sys/linker.h>
64 #include <sys/rwlock.h>
65 #include <sys/sdt.h>
66 #include <sys/stat.h>
67 #include <sys/sx.h>
68 #include <sys/unistd.h>
69 #include <sys/vnode.h>
70 #include <sys/priv.h>
71 #include <sys/proc.h>
72 #include <sys/dirent.h>
73 #include <sys/jail.h>
74 #include <sys/syscallsubr.h>
75 #include <sys/sysctl.h>
76 #ifdef KTRACE
77 #include <sys/ktrace.h>
78 #endif
79 
80 #include <machine/stdarg.h>
81 
82 #include <security/audit/audit.h>
83 #include <security/mac/mac_framework.h>
84 
85 #include <vm/vm.h>
86 #include <vm/vm_object.h>
87 #include <vm/vm_page.h>
88 #include <vm/uma.h>
89 
90 #include <ufs/ufs/quota.h>
91 
92 MALLOC_DEFINE(M_FADVISE, "fadvise", "posix_fadvise(2) information");
93 
94 SDT_PROVIDER_DEFINE(vfs);
95 SDT_PROBE_DEFINE2(vfs, , stat, mode, "char *", "int");
96 SDT_PROBE_DEFINE2(vfs, , stat, reg, "char *", "int");
97 
98 static int kern_chflagsat(struct thread *td, int fd, const char *path,
99     enum uio_seg pathseg, u_long flags, int atflag);
100 static int setfflags(struct thread *td, struct vnode *, u_long);
101 static int getutimes(const struct timeval *, enum uio_seg, struct timespec *);
102 static int getutimens(const struct timespec *, enum uio_seg,
103     struct timespec *, int *);
104 static int setutimes(struct thread *td, struct vnode *,
105     const struct timespec *, int, int);
106 static int vn_access(struct vnode *vp, int user_flags, struct ucred *cred,
107     struct thread *td);
108 static int kern_fhlinkat(struct thread *td, int fd, const char *path,
109     enum uio_seg pathseg, fhandle_t *fhp);
110 static int kern_getfhat(struct thread *td, int flags, int fd,
111     const char *path, enum uio_seg pathseg, fhandle_t *fhp);
112 static int kern_readlink_vp(struct vnode *vp, char *buf, enum uio_seg bufseg,
113     size_t count, struct thread *td);
114 static int kern_linkat_vp(struct thread *td, struct vnode *vp, int fd,
115     const char *path, enum uio_seg segflag);
116 
117 /*
118  * Sync each mounted filesystem.
119  */
120 #ifndef _SYS_SYSPROTO_H_
121 struct sync_args {
122 	int     dummy;
123 };
124 #endif
125 /* ARGSUSED */
126 int
sys_sync(struct thread * td,struct sync_args * uap)127 sys_sync(struct thread *td, struct sync_args *uap)
128 {
129 	struct mount *mp, *nmp;
130 	int save;
131 
132 	mtx_lock(&mountlist_mtx);
133 	for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
134 		if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) {
135 			nmp = TAILQ_NEXT(mp, mnt_list);
136 			continue;
137 		}
138 		if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
139 		    vn_start_write(NULL, &mp, V_NOWAIT) == 0) {
140 			save = curthread_pflags_set(TDP_SYNCIO);
141 			vfs_msync(mp, MNT_NOWAIT);
142 			VFS_SYNC(mp, MNT_NOWAIT);
143 			curthread_pflags_restore(save);
144 			vn_finished_write(mp);
145 		}
146 		mtx_lock(&mountlist_mtx);
147 		nmp = TAILQ_NEXT(mp, mnt_list);
148 		vfs_unbusy(mp);
149 	}
150 	mtx_unlock(&mountlist_mtx);
151 	return (0);
152 }
153 
154 /*
155  * Change filesystem quotas.
156  */
157 #ifndef _SYS_SYSPROTO_H_
158 struct quotactl_args {
159 	char *path;
160 	int cmd;
161 	int uid;
162 	caddr_t arg;
163 };
164 #endif
165 int
sys_quotactl(struct thread * td,struct quotactl_args * uap)166 sys_quotactl(struct thread *td, struct quotactl_args *uap)
167 {
168 	struct mount *mp;
169 	struct nameidata nd;
170 	int error;
171 
172 	AUDIT_ARG_CMD(uap->cmd);
173 	AUDIT_ARG_UID(uap->uid);
174 	if (!prison_allow(td->td_ucred, PR_ALLOW_QUOTAS))
175 		return (EPERM);
176 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
177 	    uap->path, td);
178 	if ((error = namei(&nd)) != 0)
179 		return (error);
180 	NDFREE(&nd, NDF_ONLY_PNBUF);
181 	mp = nd.ni_vp->v_mount;
182 	vfs_ref(mp);
183 	vput(nd.ni_vp);
184 	error = vfs_busy(mp, 0);
185 	vfs_rel(mp);
186 	if (error != 0)
187 		return (error);
188 	error = VFS_QUOTACTL(mp, uap->cmd, uap->uid, uap->arg);
189 
190 	/*
191 	 * Since quota on operation typically needs to open quota
192 	 * file, the Q_QUOTAON handler needs to unbusy the mount point
193 	 * before calling into namei.  Otherwise, unmount might be
194 	 * started between two vfs_busy() invocations (first is our,
195 	 * second is from mount point cross-walk code in lookup()),
196 	 * causing deadlock.
197 	 *
198 	 * Require that Q_QUOTAON handles the vfs_busy() reference on
199 	 * its own, always returning with ubusied mount point.
200 	 */
201 	if ((uap->cmd >> SUBCMDSHIFT) != Q_QUOTAON &&
202 	    (uap->cmd >> SUBCMDSHIFT) != Q_QUOTAOFF)
203 		vfs_unbusy(mp);
204 	return (error);
205 }
206 
207 /*
208  * Used by statfs conversion routines to scale the block size up if
209  * necessary so that all of the block counts are <= 'max_size'.  Note
210  * that 'max_size' should be a bitmask, i.e. 2^n - 1 for some non-zero
211  * value of 'n'.
212  */
213 void
statfs_scale_blocks(struct statfs * sf,long max_size)214 statfs_scale_blocks(struct statfs *sf, long max_size)
215 {
216 	uint64_t count;
217 	int shift;
218 
219 	KASSERT(powerof2(max_size + 1), ("%s: invalid max_size", __func__));
220 
221 	/*
222 	 * Attempt to scale the block counts to give a more accurate
223 	 * overview to userland of the ratio of free space to used
224 	 * space.  To do this, find the largest block count and compute
225 	 * a divisor that lets it fit into a signed integer <= max_size.
226 	 */
227 	if (sf->f_bavail < 0)
228 		count = -sf->f_bavail;
229 	else
230 		count = sf->f_bavail;
231 	count = MAX(sf->f_blocks, MAX(sf->f_bfree, count));
232 	if (count <= max_size)
233 		return;
234 
235 	count >>= flsl(max_size);
236 	shift = 0;
237 	while (count > 0) {
238 		shift++;
239 		count >>=1;
240 	}
241 
242 	sf->f_bsize <<= shift;
243 	sf->f_blocks >>= shift;
244 	sf->f_bfree >>= shift;
245 	sf->f_bavail >>= shift;
246 }
247 
248 static int
kern_do_statfs(struct thread * td,struct mount * mp,struct statfs * buf)249 kern_do_statfs(struct thread *td, struct mount *mp, struct statfs *buf)
250 {
251 	struct statfs *sp;
252 	int error;
253 
254 	if (mp == NULL)
255 		return (EBADF);
256 	error = vfs_busy(mp, 0);
257 	vfs_rel(mp);
258 	if (error != 0)
259 		return (error);
260 #ifdef MAC
261 	error = mac_mount_check_stat(td->td_ucred, mp);
262 	if (error != 0)
263 		goto out;
264 #endif
265 	/*
266 	 * Set these in case the underlying filesystem fails to do so.
267 	 */
268 	sp = &mp->mnt_stat;
269 	sp->f_version = STATFS_VERSION;
270 	sp->f_namemax = NAME_MAX;
271 	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
272 	error = VFS_STATFS(mp, sp);
273 	if (error != 0)
274 		goto out;
275 	*buf = *sp;
276 	if (priv_check(td, PRIV_VFS_GENERATION)) {
277 		buf->f_fsid.val[0] = buf->f_fsid.val[1] = 0;
278 		prison_enforce_statfs(td->td_ucred, mp, buf);
279 	}
280 out:
281 	vfs_unbusy(mp);
282 	return (error);
283 }
284 
285 /*
286  * Get filesystem statistics.
287  */
288 #ifndef _SYS_SYSPROTO_H_
289 struct statfs_args {
290 	char *path;
291 	struct statfs *buf;
292 };
293 #endif
294 int
sys_statfs(struct thread * td,struct statfs_args * uap)295 sys_statfs(struct thread *td, struct statfs_args *uap)
296 {
297 	struct statfs *sfp;
298 	int error;
299 
300 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
301 	error = kern_statfs(td, uap->path, UIO_USERSPACE, sfp);
302 	if (error == 0)
303 		error = copyout(sfp, uap->buf, sizeof(struct statfs));
304 	free(sfp, M_STATFS);
305 	return (error);
306 }
307 
308 int
kern_statfs(struct thread * td,char * path,enum uio_seg pathseg,struct statfs * buf)309 kern_statfs(struct thread *td, char *path, enum uio_seg pathseg,
310     struct statfs *buf)
311 {
312 	struct mount *mp;
313 	struct nameidata nd;
314 	int error;
315 
316 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
317 	    pathseg, path, td);
318 	error = namei(&nd);
319 	if (error != 0)
320 		return (error);
321 	mp = nd.ni_vp->v_mount;
322 	vfs_ref(mp);
323 	NDFREE(&nd, NDF_ONLY_PNBUF);
324 	vput(nd.ni_vp);
325 	return (kern_do_statfs(td, mp, buf));
326 }
327 
328 /*
329  * Get filesystem statistics.
330  */
331 #ifndef _SYS_SYSPROTO_H_
332 struct fstatfs_args {
333 	int fd;
334 	struct statfs *buf;
335 };
336 #endif
337 int
sys_fstatfs(struct thread * td,struct fstatfs_args * uap)338 sys_fstatfs(struct thread *td, struct fstatfs_args *uap)
339 {
340 	struct statfs *sfp;
341 	int error;
342 
343 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
344 	error = kern_fstatfs(td, uap->fd, sfp);
345 	if (error == 0)
346 		error = copyout(sfp, uap->buf, sizeof(struct statfs));
347 	free(sfp, M_STATFS);
348 	return (error);
349 }
350 
351 int
kern_fstatfs(struct thread * td,int fd,struct statfs * buf)352 kern_fstatfs(struct thread *td, int fd, struct statfs *buf)
353 {
354 	struct file *fp;
355 	struct mount *mp;
356 	struct vnode *vp;
357 	int error;
358 
359 	AUDIT_ARG_FD(fd);
360 	error = getvnode(td, fd, &cap_fstatfs_rights, &fp);
361 	if (error != 0)
362 		return (error);
363 	vp = fp->f_vnode;
364 	vn_lock(vp, LK_SHARED | LK_RETRY);
365 #ifdef AUDIT
366 	AUDIT_ARG_VNODE1(vp);
367 #endif
368 	mp = vp->v_mount;
369 	if (mp != NULL)
370 		vfs_ref(mp);
371 	VOP_UNLOCK(vp, 0);
372 	fdrop(fp, td);
373 	return (kern_do_statfs(td, mp, buf));
374 }
375 
376 /*
377  * Get statistics on all filesystems.
378  */
379 #ifndef _SYS_SYSPROTO_H_
380 struct getfsstat_args {
381 	struct statfs *buf;
382 	long bufsize;
383 	int mode;
384 };
385 #endif
386 int
sys_getfsstat(struct thread * td,struct getfsstat_args * uap)387 sys_getfsstat(struct thread *td, struct getfsstat_args *uap)
388 {
389 	size_t count;
390 	int error;
391 
392 	if (uap->bufsize < 0 || uap->bufsize > SIZE_MAX)
393 		return (EINVAL);
394 	error = kern_getfsstat(td, &uap->buf, uap->bufsize, &count,
395 	    UIO_USERSPACE, uap->mode);
396 	if (error == 0)
397 		td->td_retval[0] = count;
398 	return (error);
399 }
400 
401 /*
402  * If (bufsize > 0 && bufseg == UIO_SYSSPACE)
403  *	The caller is responsible for freeing memory which will be allocated
404  *	in '*buf'.
405  */
406 int
kern_getfsstat(struct thread * td,struct statfs ** buf,size_t bufsize,size_t * countp,enum uio_seg bufseg,int mode)407 kern_getfsstat(struct thread *td, struct statfs **buf, size_t bufsize,
408     size_t *countp, enum uio_seg bufseg, int mode)
409 {
410 	struct mount *mp, *nmp;
411 	struct statfs *sfsp, *sp, *sptmp, *tofree;
412 	size_t count, maxcount;
413 	int error;
414 
415 	switch (mode) {
416 	case MNT_WAIT:
417 	case MNT_NOWAIT:
418 		break;
419 	default:
420 		if (bufseg == UIO_SYSSPACE)
421 			*buf = NULL;
422 		return (EINVAL);
423 	}
424 restart:
425 	maxcount = bufsize / sizeof(struct statfs);
426 	if (bufsize == 0) {
427 		sfsp = NULL;
428 		tofree = NULL;
429 	} else if (bufseg == UIO_USERSPACE) {
430 		sfsp = *buf;
431 		tofree = NULL;
432 	} else /* if (bufseg == UIO_SYSSPACE) */ {
433 		count = 0;
434 		mtx_lock(&mountlist_mtx);
435 		TAILQ_FOREACH(mp, &mountlist, mnt_list) {
436 			count++;
437 		}
438 		mtx_unlock(&mountlist_mtx);
439 		if (maxcount > count)
440 			maxcount = count;
441 		tofree = sfsp = *buf = malloc(maxcount * sizeof(struct statfs),
442 		    M_STATFS, M_WAITOK);
443 	}
444 	count = 0;
445 	mtx_lock(&mountlist_mtx);
446 	for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
447 		if (prison_canseemount(td->td_ucred, mp) != 0) {
448 			nmp = TAILQ_NEXT(mp, mnt_list);
449 			continue;
450 		}
451 #ifdef MAC
452 		if (mac_mount_check_stat(td->td_ucred, mp) != 0) {
453 			nmp = TAILQ_NEXT(mp, mnt_list);
454 			continue;
455 		}
456 #endif
457 		if (mode == MNT_WAIT) {
458 			if (vfs_busy(mp, MBF_MNTLSTLOCK) != 0) {
459 				/*
460 				 * If vfs_busy() failed, and MBF_NOWAIT
461 				 * wasn't passed, then the mp is gone.
462 				 * Furthermore, because of MBF_MNTLSTLOCK,
463 				 * the mountlist_mtx was dropped.  We have
464 				 * no other choice than to start over.
465 				 */
466 				mtx_unlock(&mountlist_mtx);
467 				free(tofree, M_STATFS);
468 				goto restart;
469 			}
470 		} else {
471 			if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) {
472 				nmp = TAILQ_NEXT(mp, mnt_list);
473 				continue;
474 			}
475 		}
476 		if (sfsp != NULL && count < maxcount) {
477 			sp = &mp->mnt_stat;
478 			/*
479 			 * Set these in case the underlying filesystem
480 			 * fails to do so.
481 			 */
482 			sp->f_version = STATFS_VERSION;
483 			sp->f_namemax = NAME_MAX;
484 			sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
485 			/*
486 			 * If MNT_NOWAIT is specified, do not refresh
487 			 * the fsstat cache.
488 			 */
489 			if (mode != MNT_NOWAIT) {
490 				error = VFS_STATFS(mp, sp);
491 				if (error != 0) {
492 					mtx_lock(&mountlist_mtx);
493 					nmp = TAILQ_NEXT(mp, mnt_list);
494 					vfs_unbusy(mp);
495 					continue;
496 				}
497 			}
498 			if (priv_check(td, PRIV_VFS_GENERATION)) {
499 				sptmp = malloc(sizeof(struct statfs), M_STATFS,
500 				    M_WAITOK);
501 				*sptmp = *sp;
502 				sptmp->f_fsid.val[0] = sptmp->f_fsid.val[1] = 0;
503 				prison_enforce_statfs(td->td_ucred, mp, sptmp);
504 				sp = sptmp;
505 			} else
506 				sptmp = NULL;
507 			if (bufseg == UIO_SYSSPACE) {
508 				bcopy(sp, sfsp, sizeof(*sp));
509 				free(sptmp, M_STATFS);
510 			} else /* if (bufseg == UIO_USERSPACE) */ {
511 				error = copyout(sp, sfsp, sizeof(*sp));
512 				free(sptmp, M_STATFS);
513 				if (error != 0) {
514 					vfs_unbusy(mp);
515 					return (error);
516 				}
517 			}
518 			sfsp++;
519 		}
520 		count++;
521 		mtx_lock(&mountlist_mtx);
522 		nmp = TAILQ_NEXT(mp, mnt_list);
523 		vfs_unbusy(mp);
524 	}
525 	mtx_unlock(&mountlist_mtx);
526 	if (sfsp != NULL && count > maxcount)
527 		*countp = maxcount;
528 	else
529 		*countp = count;
530 	return (0);
531 }
532 
533 #ifdef COMPAT_FREEBSD4
534 /*
535  * Get old format filesystem statistics.
536  */
537 static void freebsd4_cvtstatfs(struct statfs *, struct ostatfs *);
538 
539 #ifndef _SYS_SYSPROTO_H_
540 struct freebsd4_statfs_args {
541 	char *path;
542 	struct ostatfs *buf;
543 };
544 #endif
545 int
freebsd4_statfs(struct thread * td,struct freebsd4_statfs_args * uap)546 freebsd4_statfs(struct thread *td, struct freebsd4_statfs_args *uap)
547 {
548 	struct ostatfs osb;
549 	struct statfs *sfp;
550 	int error;
551 
552 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
553 	error = kern_statfs(td, uap->path, UIO_USERSPACE, sfp);
554 	if (error == 0) {
555 		freebsd4_cvtstatfs(sfp, &osb);
556 		error = copyout(&osb, uap->buf, sizeof(osb));
557 	}
558 	free(sfp, M_STATFS);
559 	return (error);
560 }
561 
562 /*
563  * Get filesystem statistics.
564  */
565 #ifndef _SYS_SYSPROTO_H_
566 struct freebsd4_fstatfs_args {
567 	int fd;
568 	struct ostatfs *buf;
569 };
570 #endif
571 int
freebsd4_fstatfs(struct thread * td,struct freebsd4_fstatfs_args * uap)572 freebsd4_fstatfs(struct thread *td, struct freebsd4_fstatfs_args *uap)
573 {
574 	struct ostatfs osb;
575 	struct statfs *sfp;
576 	int error;
577 
578 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
579 	error = kern_fstatfs(td, uap->fd, sfp);
580 	if (error == 0) {
581 		freebsd4_cvtstatfs(sfp, &osb);
582 		error = copyout(&osb, uap->buf, sizeof(osb));
583 	}
584 	free(sfp, M_STATFS);
585 	return (error);
586 }
587 
588 /*
589  * Get statistics on all filesystems.
590  */
591 #ifndef _SYS_SYSPROTO_H_
592 struct freebsd4_getfsstat_args {
593 	struct ostatfs *buf;
594 	long bufsize;
595 	int mode;
596 };
597 #endif
598 int
freebsd4_getfsstat(struct thread * td,struct freebsd4_getfsstat_args * uap)599 freebsd4_getfsstat(struct thread *td, struct freebsd4_getfsstat_args *uap)
600 {
601 	struct statfs *buf, *sp;
602 	struct ostatfs osb;
603 	size_t count, size;
604 	int error;
605 
606 	if (uap->bufsize < 0)
607 		return (EINVAL);
608 	count = uap->bufsize / sizeof(struct ostatfs);
609 	if (count > SIZE_MAX / sizeof(struct statfs))
610 		return (EINVAL);
611 	size = count * sizeof(struct statfs);
612 	error = kern_getfsstat(td, &buf, size, &count, UIO_SYSSPACE,
613 	    uap->mode);
614 	if (error == 0)
615 		td->td_retval[0] = count;
616 	if (size != 0) {
617 		sp = buf;
618 		while (count != 0 && error == 0) {
619 			freebsd4_cvtstatfs(sp, &osb);
620 			error = copyout(&osb, uap->buf, sizeof(osb));
621 			sp++;
622 			uap->buf++;
623 			count--;
624 		}
625 		free(buf, M_STATFS);
626 	}
627 	return (error);
628 }
629 
630 /*
631  * Implement fstatfs() for (NFS) file handles.
632  */
633 #ifndef _SYS_SYSPROTO_H_
634 struct freebsd4_fhstatfs_args {
635 	struct fhandle *u_fhp;
636 	struct ostatfs *buf;
637 };
638 #endif
639 int
freebsd4_fhstatfs(struct thread * td,struct freebsd4_fhstatfs_args * uap)640 freebsd4_fhstatfs(struct thread *td, struct freebsd4_fhstatfs_args *uap)
641 {
642 	struct ostatfs osb;
643 	struct statfs *sfp;
644 	fhandle_t fh;
645 	int error;
646 
647 	error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
648 	if (error != 0)
649 		return (error);
650 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
651 	error = kern_fhstatfs(td, fh, sfp);
652 	if (error == 0) {
653 		freebsd4_cvtstatfs(sfp, &osb);
654 		error = copyout(&osb, uap->buf, sizeof(osb));
655 	}
656 	free(sfp, M_STATFS);
657 	return (error);
658 }
659 
660 /*
661  * Convert a new format statfs structure to an old format statfs structure.
662  */
663 static void
freebsd4_cvtstatfs(struct statfs * nsp,struct ostatfs * osp)664 freebsd4_cvtstatfs(struct statfs *nsp, struct ostatfs *osp)
665 {
666 
667 	statfs_scale_blocks(nsp, LONG_MAX);
668 	bzero(osp, sizeof(*osp));
669 	osp->f_bsize = nsp->f_bsize;
670 	osp->f_iosize = MIN(nsp->f_iosize, LONG_MAX);
671 	osp->f_blocks = nsp->f_blocks;
672 	osp->f_bfree = nsp->f_bfree;
673 	osp->f_bavail = nsp->f_bavail;
674 	osp->f_files = MIN(nsp->f_files, LONG_MAX);
675 	osp->f_ffree = MIN(nsp->f_ffree, LONG_MAX);
676 	osp->f_owner = nsp->f_owner;
677 	osp->f_type = nsp->f_type;
678 	osp->f_flags = nsp->f_flags;
679 	osp->f_syncwrites = MIN(nsp->f_syncwrites, LONG_MAX);
680 	osp->f_asyncwrites = MIN(nsp->f_asyncwrites, LONG_MAX);
681 	osp->f_syncreads = MIN(nsp->f_syncreads, LONG_MAX);
682 	osp->f_asyncreads = MIN(nsp->f_asyncreads, LONG_MAX);
683 	strlcpy(osp->f_fstypename, nsp->f_fstypename,
684 	    MIN(MFSNAMELEN, OMFSNAMELEN));
685 	strlcpy(osp->f_mntonname, nsp->f_mntonname,
686 	    MIN(MNAMELEN, OMNAMELEN));
687 	strlcpy(osp->f_mntfromname, nsp->f_mntfromname,
688 	    MIN(MNAMELEN, OMNAMELEN));
689 	osp->f_fsid = nsp->f_fsid;
690 }
691 #endif /* COMPAT_FREEBSD4 */
692 
693 #if defined(COMPAT_FREEBSD11)
694 /*
695  * Get old format filesystem statistics.
696  */
697 static void freebsd11_cvtstatfs(struct statfs *, struct freebsd11_statfs *);
698 
699 int
freebsd11_statfs(struct thread * td,struct freebsd11_statfs_args * uap)700 freebsd11_statfs(struct thread *td, struct freebsd11_statfs_args *uap)
701 {
702 	struct freebsd11_statfs osb;
703 	struct statfs *sfp;
704 	int error;
705 
706 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
707 	error = kern_statfs(td, uap->path, UIO_USERSPACE, sfp);
708 	if (error == 0) {
709 		freebsd11_cvtstatfs(sfp, &osb);
710 		error = copyout(&osb, uap->buf, sizeof(osb));
711 	}
712 	free(sfp, M_STATFS);
713 	return (error);
714 }
715 
716 /*
717  * Get filesystem statistics.
718  */
719 int
freebsd11_fstatfs(struct thread * td,struct freebsd11_fstatfs_args * uap)720 freebsd11_fstatfs(struct thread *td, struct freebsd11_fstatfs_args *uap)
721 {
722 	struct freebsd11_statfs osb;
723 	struct statfs *sfp;
724 	int error;
725 
726 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
727 	error = kern_fstatfs(td, uap->fd, sfp);
728 	if (error == 0) {
729 		freebsd11_cvtstatfs(sfp, &osb);
730 		error = copyout(&osb, uap->buf, sizeof(osb));
731 	}
732 	free(sfp, M_STATFS);
733 	return (error);
734 }
735 
736 /*
737  * Get statistics on all filesystems.
738  */
739 int
freebsd11_getfsstat(struct thread * td,struct freebsd11_getfsstat_args * uap)740 freebsd11_getfsstat(struct thread *td, struct freebsd11_getfsstat_args *uap)
741 {
742 	struct freebsd11_statfs osb;
743 	struct statfs *buf, *sp;
744 	size_t count, size;
745 	int error;
746 
747 	count = uap->bufsize / sizeof(struct ostatfs);
748 	size = count * sizeof(struct statfs);
749 	error = kern_getfsstat(td, &buf, size, &count, UIO_SYSSPACE,
750 	    uap->mode);
751 	if (error == 0)
752 		td->td_retval[0] = count;
753 	if (size > 0) {
754 		sp = buf;
755 		while (count > 0 && error == 0) {
756 			freebsd11_cvtstatfs(sp, &osb);
757 			error = copyout(&osb, uap->buf, sizeof(osb));
758 			sp++;
759 			uap->buf++;
760 			count--;
761 		}
762 		free(buf, M_STATFS);
763 	}
764 	return (error);
765 }
766 
767 /*
768  * Implement fstatfs() for (NFS) file handles.
769  */
770 int
freebsd11_fhstatfs(struct thread * td,struct freebsd11_fhstatfs_args * uap)771 freebsd11_fhstatfs(struct thread *td, struct freebsd11_fhstatfs_args *uap)
772 {
773 	struct freebsd11_statfs osb;
774 	struct statfs *sfp;
775 	fhandle_t fh;
776 	int error;
777 
778 	error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
779 	if (error)
780 		return (error);
781 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
782 	error = kern_fhstatfs(td, fh, sfp);
783 	if (error == 0) {
784 		freebsd11_cvtstatfs(sfp, &osb);
785 		error = copyout(&osb, uap->buf, sizeof(osb));
786 	}
787 	free(sfp, M_STATFS);
788 	return (error);
789 }
790 
791 /*
792  * Convert a new format statfs structure to an old format statfs structure.
793  */
794 static void
freebsd11_cvtstatfs(struct statfs * nsp,struct freebsd11_statfs * osp)795 freebsd11_cvtstatfs(struct statfs *nsp, struct freebsd11_statfs *osp)
796 {
797 
798 	bzero(osp, sizeof(*osp));
799 	osp->f_version = FREEBSD11_STATFS_VERSION;
800 	osp->f_type = nsp->f_type;
801 	osp->f_flags = nsp->f_flags;
802 	osp->f_bsize = nsp->f_bsize;
803 	osp->f_iosize = nsp->f_iosize;
804 	osp->f_blocks = nsp->f_blocks;
805 	osp->f_bfree = nsp->f_bfree;
806 	osp->f_bavail = nsp->f_bavail;
807 	osp->f_files = nsp->f_files;
808 	osp->f_ffree = nsp->f_ffree;
809 	osp->f_syncwrites = nsp->f_syncwrites;
810 	osp->f_asyncwrites = nsp->f_asyncwrites;
811 	osp->f_syncreads = nsp->f_syncreads;
812 	osp->f_asyncreads = nsp->f_asyncreads;
813 	osp->f_namemax = nsp->f_namemax;
814 	osp->f_owner = nsp->f_owner;
815 	osp->f_fsid = nsp->f_fsid;
816 	strlcpy(osp->f_fstypename, nsp->f_fstypename,
817 	    MIN(MFSNAMELEN, sizeof(osp->f_fstypename)));
818 	strlcpy(osp->f_mntonname, nsp->f_mntonname,
819 	    MIN(MNAMELEN, sizeof(osp->f_mntonname)));
820 	strlcpy(osp->f_mntfromname, nsp->f_mntfromname,
821 	    MIN(MNAMELEN, sizeof(osp->f_mntfromname)));
822 }
823 #endif /* COMPAT_FREEBSD11 */
824 
825 /*
826  * Change current working directory to a given file descriptor.
827  */
828 #ifndef _SYS_SYSPROTO_H_
829 struct fchdir_args {
830 	int	fd;
831 };
832 #endif
833 int
sys_fchdir(struct thread * td,struct fchdir_args * uap)834 sys_fchdir(struct thread *td, struct fchdir_args *uap)
835 {
836 	struct vnode *vp, *tdp;
837 	struct mount *mp;
838 	struct file *fp;
839 	int error;
840 
841 	AUDIT_ARG_FD(uap->fd);
842 	error = getvnode(td, uap->fd, &cap_fchdir_rights,
843 	    &fp);
844 	if (error != 0)
845 		return (error);
846 	vp = fp->f_vnode;
847 	vrefact(vp);
848 	fdrop(fp, td);
849 	vn_lock(vp, LK_SHARED | LK_RETRY);
850 	AUDIT_ARG_VNODE1(vp);
851 	error = change_dir(vp, td);
852 	while (!error && (mp = vp->v_mountedhere) != NULL) {
853 		if (vfs_busy(mp, 0))
854 			continue;
855 		error = VFS_ROOT(mp, LK_SHARED, &tdp);
856 		vfs_unbusy(mp);
857 		if (error != 0)
858 			break;
859 		vput(vp);
860 		vp = tdp;
861 	}
862 	if (error != 0) {
863 		vput(vp);
864 		return (error);
865 	}
866 	VOP_UNLOCK(vp, 0);
867 	pwd_chdir(td, vp);
868 	return (0);
869 }
870 
871 /*
872  * Change current working directory (``.'').
873  */
874 #ifndef _SYS_SYSPROTO_H_
875 struct chdir_args {
876 	char	*path;
877 };
878 #endif
879 int
sys_chdir(struct thread * td,struct chdir_args * uap)880 sys_chdir(struct thread *td, struct chdir_args *uap)
881 {
882 
883 	return (kern_chdir(td, uap->path, UIO_USERSPACE));
884 }
885 
886 int
kern_chdir(struct thread * td,char * path,enum uio_seg pathseg)887 kern_chdir(struct thread *td, char *path, enum uio_seg pathseg)
888 {
889 	struct nameidata nd;
890 	int error;
891 
892 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
893 	    pathseg, path, td);
894 	if ((error = namei(&nd)) != 0)
895 		return (error);
896 	if ((error = change_dir(nd.ni_vp, td)) != 0) {
897 		vput(nd.ni_vp);
898 		NDFREE(&nd, NDF_ONLY_PNBUF);
899 		return (error);
900 	}
901 	VOP_UNLOCK(nd.ni_vp, 0);
902 	NDFREE(&nd, NDF_ONLY_PNBUF);
903 	pwd_chdir(td, nd.ni_vp);
904 	return (0);
905 }
906 
907 /*
908  * Change notion of root (``/'') directory.
909  */
910 #ifndef _SYS_SYSPROTO_H_
911 struct chroot_args {
912 	char	*path;
913 };
914 #endif
915 int
sys_chroot(struct thread * td,struct chroot_args * uap)916 sys_chroot(struct thread *td, struct chroot_args *uap)
917 {
918 	struct nameidata nd;
919 	int error;
920 
921 	error = priv_check(td, PRIV_VFS_CHROOT);
922 	if (error != 0)
923 		return (error);
924 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
925 	    UIO_USERSPACE, uap->path, td);
926 	error = namei(&nd);
927 	if (error != 0)
928 		goto error;
929 	error = change_dir(nd.ni_vp, td);
930 	if (error != 0)
931 		goto e_vunlock;
932 #ifdef MAC
933 	error = mac_vnode_check_chroot(td->td_ucred, nd.ni_vp);
934 	if (error != 0)
935 		goto e_vunlock;
936 #endif
937 	VOP_UNLOCK(nd.ni_vp, 0);
938 	error = pwd_chroot(td, nd.ni_vp);
939 	vrele(nd.ni_vp);
940 	NDFREE(&nd, NDF_ONLY_PNBUF);
941 	return (error);
942 e_vunlock:
943 	vput(nd.ni_vp);
944 error:
945 	NDFREE(&nd, NDF_ONLY_PNBUF);
946 	return (error);
947 }
948 
949 /*
950  * Common routine for chroot and chdir.  Callers must provide a locked vnode
951  * instance.
952  */
953 int
change_dir(struct vnode * vp,struct thread * td)954 change_dir(struct vnode *vp, struct thread *td)
955 {
956 #ifdef MAC
957 	int error;
958 #endif
959 
960 	ASSERT_VOP_LOCKED(vp, "change_dir(): vp not locked");
961 	if (vp->v_type != VDIR)
962 		return (ENOTDIR);
963 #ifdef MAC
964 	error = mac_vnode_check_chdir(td->td_ucred, vp);
965 	if (error != 0)
966 		return (error);
967 #endif
968 	return (VOP_ACCESS(vp, VEXEC, td->td_ucred, td));
969 }
970 
971 static __inline void
flags_to_rights(int flags,cap_rights_t * rightsp)972 flags_to_rights(int flags, cap_rights_t *rightsp)
973 {
974 
975 	if (flags & O_EXEC) {
976 		cap_rights_set(rightsp, CAP_FEXECVE);
977 	} else {
978 		switch ((flags & O_ACCMODE)) {
979 		case O_RDONLY:
980 			cap_rights_set(rightsp, CAP_READ);
981 			break;
982 		case O_RDWR:
983 			cap_rights_set(rightsp, CAP_READ);
984 			/* FALLTHROUGH */
985 		case O_WRONLY:
986 			cap_rights_set(rightsp, CAP_WRITE);
987 			if (!(flags & (O_APPEND | O_TRUNC)))
988 				cap_rights_set(rightsp, CAP_SEEK);
989 			break;
990 		}
991 	}
992 
993 	if (flags & O_CREAT)
994 		cap_rights_set(rightsp, CAP_CREATE);
995 
996 	if (flags & O_TRUNC)
997 		cap_rights_set(rightsp, CAP_FTRUNCATE);
998 
999 	if (flags & (O_SYNC | O_FSYNC))
1000 		cap_rights_set(rightsp, CAP_FSYNC);
1001 
1002 	if (flags & (O_EXLOCK | O_SHLOCK))
1003 		cap_rights_set(rightsp, CAP_FLOCK);
1004 }
1005 
1006 /*
1007  * Check permissions, allocate an open file structure, and call the device
1008  * open routine if any.
1009  */
1010 #ifndef _SYS_SYSPROTO_H_
1011 struct open_args {
1012 	char	*path;
1013 	int	flags;
1014 	int	mode;
1015 };
1016 #endif
1017 int
sys_open(struct thread * td,struct open_args * uap)1018 sys_open(struct thread *td, struct open_args *uap)
1019 {
1020 
1021 	return (kern_openat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
1022 	    uap->flags, uap->mode));
1023 }
1024 
1025 #ifndef _SYS_SYSPROTO_H_
1026 struct openat_args {
1027 	int	fd;
1028 	char	*path;
1029 	int	flag;
1030 	int	mode;
1031 };
1032 #endif
1033 int
sys_openat(struct thread * td,struct openat_args * uap)1034 sys_openat(struct thread *td, struct openat_args *uap)
1035 {
1036 
1037 	AUDIT_ARG_FD(uap->fd);
1038 	return (kern_openat(td, uap->fd, uap->path, UIO_USERSPACE, uap->flag,
1039 	    uap->mode));
1040 }
1041 
1042 int
kern_openat(struct thread * td,int fd,char * path,enum uio_seg pathseg,int flags,int mode)1043 kern_openat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1044     int flags, int mode)
1045 {
1046 	struct proc *p = td->td_proc;
1047 	struct filedesc *fdp = p->p_fd;
1048 	struct file *fp;
1049 	struct vnode *vp;
1050 	struct nameidata nd;
1051 	cap_rights_t rights;
1052 	int cmode, error, indx;
1053 
1054 	indx = -1;
1055 
1056 	AUDIT_ARG_FFLAGS(flags);
1057 	AUDIT_ARG_MODE(mode);
1058 	cap_rights_init(&rights, CAP_LOOKUP);
1059 	flags_to_rights(flags, &rights);
1060 	/*
1061 	 * Only one of the O_EXEC, O_RDONLY, O_WRONLY and O_RDWR flags
1062 	 * may be specified.
1063 	 */
1064 	if (flags & O_EXEC) {
1065 		if (flags & O_ACCMODE)
1066 			return (EINVAL);
1067 	} else if ((flags & O_ACCMODE) == O_ACCMODE) {
1068 		return (EINVAL);
1069 	} else {
1070 		flags = FFLAGS(flags);
1071 	}
1072 
1073 	/*
1074 	 * Allocate a file structure. The descriptor to reference it
1075 	 * is allocated and set by finstall() below.
1076 	 */
1077 	error = falloc_noinstall(td, &fp);
1078 	if (error != 0)
1079 		return (error);
1080 	/*
1081 	 * An extra reference on `fp' has been held for us by
1082 	 * falloc_noinstall().
1083 	 */
1084 	/* Set the flags early so the finit in devfs can pick them up. */
1085 	fp->f_flag = flags & FMASK;
1086 	cmode = ((mode & ~fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT;
1087 	NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, fd,
1088 	    &rights, td);
1089 	td->td_dupfd = -1;		/* XXX check for fdopen */
1090 	error = vn_open(&nd, &flags, cmode, fp);
1091 	if (error != 0) {
1092 		/*
1093 		 * If the vn_open replaced the method vector, something
1094 		 * wonderous happened deep below and we just pass it up
1095 		 * pretending we know what we do.
1096 		 */
1097 		if (error == ENXIO && fp->f_ops != &badfileops)
1098 			goto success;
1099 
1100 		/*
1101 		 * Handle special fdopen() case. bleh.
1102 		 *
1103 		 * Don't do this for relative (capability) lookups; we don't
1104 		 * understand exactly what would happen, and we don't think
1105 		 * that it ever should.
1106 		 */
1107 		if ((nd.ni_lcf & NI_LCF_STRICTRELATIVE) == 0 &&
1108 		    (error == ENODEV || error == ENXIO) &&
1109 		    td->td_dupfd >= 0) {
1110 			error = dupfdopen(td, fdp, td->td_dupfd, flags, error,
1111 			    &indx);
1112 			if (error == 0)
1113 				goto success;
1114 		}
1115 
1116 		goto bad;
1117 	}
1118 	td->td_dupfd = 0;
1119 	NDFREE(&nd, NDF_ONLY_PNBUF);
1120 	vp = nd.ni_vp;
1121 
1122 	/*
1123 	 * Store the vnode, for any f_type. Typically, the vnode use
1124 	 * count is decremented by direct call to vn_closefile() for
1125 	 * files that switched type in the cdevsw fdopen() method.
1126 	 */
1127 	fp->f_vnode = vp;
1128 	/*
1129 	 * If the file wasn't claimed by devfs bind it to the normal
1130 	 * vnode operations here.
1131 	 */
1132 	if (fp->f_ops == &badfileops) {
1133 		KASSERT(vp->v_type != VFIFO, ("Unexpected fifo."));
1134 		fp->f_seqcount = 1;
1135 		finit(fp, (flags & FMASK) | (fp->f_flag & FHASLOCK),
1136 		    DTYPE_VNODE, vp, &vnops);
1137 	}
1138 
1139 	VOP_UNLOCK(vp, 0);
1140 	if (flags & O_TRUNC) {
1141 		error = fo_truncate(fp, 0, td->td_ucred, td);
1142 		if (error != 0)
1143 			goto bad;
1144 	}
1145 success:
1146 	/*
1147 	 * If we haven't already installed the FD (for dupfdopen), do so now.
1148 	 */
1149 	if (indx == -1) {
1150 		struct filecaps *fcaps;
1151 
1152 #ifdef CAPABILITIES
1153 		if ((nd.ni_lcf & NI_LCF_STRICTRELATIVE) != 0)
1154 			fcaps = &nd.ni_filecaps;
1155 		else
1156 #endif
1157 			fcaps = NULL;
1158 		error = finstall(td, fp, &indx, flags, fcaps);
1159 		/* On success finstall() consumes fcaps. */
1160 		if (error != 0) {
1161 			filecaps_free(&nd.ni_filecaps);
1162 			goto bad;
1163 		}
1164 	} else {
1165 		filecaps_free(&nd.ni_filecaps);
1166 	}
1167 
1168 	/*
1169 	 * Release our private reference, leaving the one associated with
1170 	 * the descriptor table intact.
1171 	 */
1172 	fdrop(fp, td);
1173 	td->td_retval[0] = indx;
1174 	return (0);
1175 bad:
1176 	KASSERT(indx == -1, ("indx=%d, should be -1", indx));
1177 	fdrop(fp, td);
1178 	return (error);
1179 }
1180 
1181 #ifdef COMPAT_43
1182 /*
1183  * Create a file.
1184  */
1185 #ifndef _SYS_SYSPROTO_H_
1186 struct ocreat_args {
1187 	char	*path;
1188 	int	mode;
1189 };
1190 #endif
1191 int
ocreat(struct thread * td,struct ocreat_args * uap)1192 ocreat(struct thread *td, struct ocreat_args *uap)
1193 {
1194 
1195 	return (kern_openat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
1196 	    O_WRONLY | O_CREAT | O_TRUNC, uap->mode));
1197 }
1198 #endif /* COMPAT_43 */
1199 
1200 /*
1201  * Create a special file.
1202  */
1203 #ifndef _SYS_SYSPROTO_H_
1204 struct mknodat_args {
1205 	int	fd;
1206 	char	*path;
1207 	mode_t	mode;
1208 	dev_t	dev;
1209 };
1210 #endif
1211 int
sys_mknodat(struct thread * td,struct mknodat_args * uap)1212 sys_mknodat(struct thread *td, struct mknodat_args *uap)
1213 {
1214 
1215 	return (kern_mknodat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode,
1216 	    uap->dev));
1217 }
1218 
1219 #if defined(COMPAT_FREEBSD11)
1220 int
freebsd11_mknod(struct thread * td,struct freebsd11_mknod_args * uap)1221 freebsd11_mknod(struct thread *td,
1222     struct freebsd11_mknod_args *uap)
1223 {
1224 
1225 	return (kern_mknodat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
1226 	    uap->mode, uap->dev));
1227 }
1228 
1229 int
freebsd11_mknodat(struct thread * td,struct freebsd11_mknodat_args * uap)1230 freebsd11_mknodat(struct thread *td,
1231     struct freebsd11_mknodat_args *uap)
1232 {
1233 
1234 	return (kern_mknodat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode,
1235 	    uap->dev));
1236 }
1237 #endif /* COMPAT_FREEBSD11 */
1238 
1239 int
kern_mknodat(struct thread * td,int fd,char * path,enum uio_seg pathseg,int mode,dev_t dev)1240 kern_mknodat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1241     int mode, dev_t dev)
1242 {
1243 	struct vnode *vp;
1244 	struct mount *mp;
1245 	struct vattr vattr;
1246 	struct nameidata nd;
1247 	int error, whiteout = 0;
1248 
1249 	AUDIT_ARG_MODE(mode);
1250 	AUDIT_ARG_DEV(dev);
1251 	switch (mode & S_IFMT) {
1252 	case S_IFCHR:
1253 	case S_IFBLK:
1254 		error = priv_check(td, PRIV_VFS_MKNOD_DEV);
1255 		if (error == 0 && dev == VNOVAL)
1256 			error = EINVAL;
1257 		break;
1258 	case S_IFWHT:
1259 		error = priv_check(td, PRIV_VFS_MKNOD_WHT);
1260 		break;
1261 	case S_IFIFO:
1262 		if (dev == 0)
1263 			return (kern_mkfifoat(td, fd, path, pathseg, mode));
1264 		/* FALLTHROUGH */
1265 	default:
1266 		error = EINVAL;
1267 		break;
1268 	}
1269 	if (error != 0)
1270 		return (error);
1271 restart:
1272 	bwillwrite();
1273 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1 |
1274 	    NOCACHE, pathseg, path, fd, &cap_mknodat_rights,
1275 	    td);
1276 	if ((error = namei(&nd)) != 0)
1277 		return (error);
1278 	vp = nd.ni_vp;
1279 	if (vp != NULL) {
1280 		NDFREE(&nd, NDF_ONLY_PNBUF);
1281 		if (vp == nd.ni_dvp)
1282 			vrele(nd.ni_dvp);
1283 		else
1284 			vput(nd.ni_dvp);
1285 		vrele(vp);
1286 		return (EEXIST);
1287 	} else {
1288 		VATTR_NULL(&vattr);
1289 		vattr.va_mode = (mode & ALLPERMS) &
1290 		    ~td->td_proc->p_fd->fd_cmask;
1291 		vattr.va_rdev = dev;
1292 		whiteout = 0;
1293 
1294 		switch (mode & S_IFMT) {
1295 		case S_IFCHR:
1296 			vattr.va_type = VCHR;
1297 			break;
1298 		case S_IFBLK:
1299 			vattr.va_type = VBLK;
1300 			break;
1301 		case S_IFWHT:
1302 			whiteout = 1;
1303 			break;
1304 		default:
1305 			panic("kern_mknod: invalid mode");
1306 		}
1307 	}
1308 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1309 		NDFREE(&nd, NDF_ONLY_PNBUF);
1310 		vput(nd.ni_dvp);
1311 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1312 			return (error);
1313 		goto restart;
1314 	}
1315 #ifdef MAC
1316 	if (error == 0 && !whiteout)
1317 		error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp,
1318 		    &nd.ni_cnd, &vattr);
1319 #endif
1320 	if (error == 0) {
1321 		if (whiteout)
1322 			error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, CREATE);
1323 		else {
1324 			error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp,
1325 						&nd.ni_cnd, &vattr);
1326 			if (error == 0)
1327 				vput(nd.ni_vp);
1328 		}
1329 	}
1330 	NDFREE(&nd, NDF_ONLY_PNBUF);
1331 	vput(nd.ni_dvp);
1332 	vn_finished_write(mp);
1333 	return (error);
1334 }
1335 
1336 /*
1337  * Create a named pipe.
1338  */
1339 #ifndef _SYS_SYSPROTO_H_
1340 struct mkfifo_args {
1341 	char	*path;
1342 	int	mode;
1343 };
1344 #endif
1345 int
sys_mkfifo(struct thread * td,struct mkfifo_args * uap)1346 sys_mkfifo(struct thread *td, struct mkfifo_args *uap)
1347 {
1348 
1349 	return (kern_mkfifoat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
1350 	    uap->mode));
1351 }
1352 
1353 #ifndef _SYS_SYSPROTO_H_
1354 struct mkfifoat_args {
1355 	int	fd;
1356 	char	*path;
1357 	mode_t	mode;
1358 };
1359 #endif
1360 int
sys_mkfifoat(struct thread * td,struct mkfifoat_args * uap)1361 sys_mkfifoat(struct thread *td, struct mkfifoat_args *uap)
1362 {
1363 
1364 	return (kern_mkfifoat(td, uap->fd, uap->path, UIO_USERSPACE,
1365 	    uap->mode));
1366 }
1367 
1368 int
kern_mkfifoat(struct thread * td,int fd,char * path,enum uio_seg pathseg,int mode)1369 kern_mkfifoat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1370     int mode)
1371 {
1372 	struct mount *mp;
1373 	struct vattr vattr;
1374 	struct nameidata nd;
1375 	int error;
1376 
1377 	AUDIT_ARG_MODE(mode);
1378 restart:
1379 	bwillwrite();
1380 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1 |
1381 	    NOCACHE, pathseg, path, fd, &cap_mkfifoat_rights,
1382 	    td);
1383 	if ((error = namei(&nd)) != 0)
1384 		return (error);
1385 	if (nd.ni_vp != NULL) {
1386 		NDFREE(&nd, NDF_ONLY_PNBUF);
1387 		if (nd.ni_vp == nd.ni_dvp)
1388 			vrele(nd.ni_dvp);
1389 		else
1390 			vput(nd.ni_dvp);
1391 		vrele(nd.ni_vp);
1392 		return (EEXIST);
1393 	}
1394 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1395 		NDFREE(&nd, NDF_ONLY_PNBUF);
1396 		vput(nd.ni_dvp);
1397 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1398 			return (error);
1399 		goto restart;
1400 	}
1401 	VATTR_NULL(&vattr);
1402 	vattr.va_type = VFIFO;
1403 	vattr.va_mode = (mode & ALLPERMS) & ~td->td_proc->p_fd->fd_cmask;
1404 #ifdef MAC
1405 	error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
1406 	    &vattr);
1407 	if (error != 0)
1408 		goto out;
1409 #endif
1410 	error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
1411 	if (error == 0)
1412 		vput(nd.ni_vp);
1413 #ifdef MAC
1414 out:
1415 #endif
1416 	vput(nd.ni_dvp);
1417 	vn_finished_write(mp);
1418 	NDFREE(&nd, NDF_ONLY_PNBUF);
1419 	return (error);
1420 }
1421 
1422 /*
1423  * Make a hard file link.
1424  */
1425 #ifndef _SYS_SYSPROTO_H_
1426 struct link_args {
1427 	char	*path;
1428 	char	*link;
1429 };
1430 #endif
1431 int
sys_link(struct thread * td,struct link_args * uap)1432 sys_link(struct thread *td, struct link_args *uap)
1433 {
1434 
1435 	return (kern_linkat(td, AT_FDCWD, AT_FDCWD, uap->path, uap->link,
1436 	    UIO_USERSPACE, FOLLOW));
1437 }
1438 
1439 #ifndef _SYS_SYSPROTO_H_
1440 struct linkat_args {
1441 	int	fd1;
1442 	char	*path1;
1443 	int	fd2;
1444 	char	*path2;
1445 	int	flag;
1446 };
1447 #endif
1448 int
sys_linkat(struct thread * td,struct linkat_args * uap)1449 sys_linkat(struct thread *td, struct linkat_args *uap)
1450 {
1451 	int flag;
1452 
1453 	flag = uap->flag;
1454 	if (flag & ~AT_SYMLINK_FOLLOW)
1455 		return (EINVAL);
1456 
1457 	return (kern_linkat(td, uap->fd1, uap->fd2, uap->path1, uap->path2,
1458 	    UIO_USERSPACE, (flag & AT_SYMLINK_FOLLOW) ? FOLLOW : NOFOLLOW));
1459 }
1460 
1461 int hardlink_check_uid = 0;
1462 SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_uid, CTLFLAG_RW,
1463     &hardlink_check_uid, 0,
1464     "Unprivileged processes cannot create hard links to files owned by other "
1465     "users");
1466 static int hardlink_check_gid = 0;
1467 SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_gid, CTLFLAG_RW,
1468     &hardlink_check_gid, 0,
1469     "Unprivileged processes cannot create hard links to files owned by other "
1470     "groups");
1471 
1472 static int
can_hardlink(struct vnode * vp,struct ucred * cred)1473 can_hardlink(struct vnode *vp, struct ucred *cred)
1474 {
1475 	struct vattr va;
1476 	int error;
1477 
1478 	if (!hardlink_check_uid && !hardlink_check_gid)
1479 		return (0);
1480 
1481 	error = VOP_GETATTR(vp, &va, cred);
1482 	if (error != 0)
1483 		return (error);
1484 
1485 	if (hardlink_check_uid && cred->cr_uid != va.va_uid) {
1486 		error = priv_check_cred(cred, PRIV_VFS_LINK, 0);
1487 		if (error != 0)
1488 			return (error);
1489 	}
1490 
1491 	if (hardlink_check_gid && !groupmember(va.va_gid, cred)) {
1492 		error = priv_check_cred(cred, PRIV_VFS_LINK, 0);
1493 		if (error != 0)
1494 			return (error);
1495 	}
1496 
1497 	return (0);
1498 }
1499 
1500 int
kern_linkat(struct thread * td,int fd1,int fd2,char * path1,char * path2,enum uio_seg segflag,int follow)1501 kern_linkat(struct thread *td, int fd1, int fd2, char *path1, char *path2,
1502     enum uio_seg segflag, int follow)
1503 {
1504 	struct nameidata nd;
1505 	int error;
1506 
1507 	do {
1508 		bwillwrite();
1509 		NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, segflag,
1510 		    path1, fd1, &cap_linkat_source_rights, td);
1511 		if ((error = namei(&nd)) != 0)
1512 			return (error);
1513 		NDFREE(&nd, NDF_ONLY_PNBUF);
1514 		error = kern_linkat_vp(td, nd.ni_vp, fd2, path2, segflag);
1515 	} while (error ==  EAGAIN);
1516 	return (error);
1517 }
1518 
1519 static int
kern_linkat_vp(struct thread * td,struct vnode * vp,int fd,const char * path,enum uio_seg segflag)1520 kern_linkat_vp(struct thread *td, struct vnode *vp, int fd, const char *path,
1521     enum uio_seg segflag)
1522 {
1523 	struct nameidata nd;
1524 	struct mount *mp;
1525 	int error;
1526 
1527 	if (vp->v_type == VDIR) {
1528 		vrele(vp);
1529 		return (EPERM);		/* POSIX */
1530 	}
1531 	NDINIT_ATRIGHTS(&nd, CREATE,
1532 	    LOCKPARENT | SAVENAME | AUDITVNODE2 | NOCACHE, segflag, path, fd,
1533 	    &cap_linkat_target_rights, td);
1534 	if ((error = namei(&nd)) == 0) {
1535 		if (nd.ni_vp != NULL) {
1536 			NDFREE(&nd, NDF_ONLY_PNBUF);
1537 			if (nd.ni_dvp == nd.ni_vp)
1538 				vrele(nd.ni_dvp);
1539 			else
1540 				vput(nd.ni_dvp);
1541 			vrele(nd.ni_vp);
1542 			vrele(vp);
1543 			return (EEXIST);
1544 		} else if (nd.ni_dvp->v_mount != vp->v_mount) {
1545 			/*
1546 			 * Cross-device link.  No need to recheck
1547 			 * vp->v_type, since it cannot change, except
1548 			 * to VBAD.
1549 			 */
1550 			NDFREE(&nd, NDF_ONLY_PNBUF);
1551 			vput(nd.ni_dvp);
1552 			vrele(vp);
1553 			return (EXDEV);
1554 		} else if ((error = vn_lock(vp, LK_EXCLUSIVE)) == 0) {
1555 			error = can_hardlink(vp, td->td_ucred);
1556 #ifdef MAC
1557 			if (error == 0)
1558 				error = mac_vnode_check_link(td->td_ucred,
1559 				    nd.ni_dvp, vp, &nd.ni_cnd);
1560 #endif
1561 			if (error != 0) {
1562 				vput(vp);
1563 				vput(nd.ni_dvp);
1564 				NDFREE(&nd, NDF_ONLY_PNBUF);
1565 				return (error);
1566 			}
1567 			error = vn_start_write(vp, &mp, V_NOWAIT);
1568 			if (error != 0) {
1569 				vput(vp);
1570 				vput(nd.ni_dvp);
1571 				NDFREE(&nd, NDF_ONLY_PNBUF);
1572 				error = vn_start_write(NULL, &mp,
1573 				    V_XSLEEP | PCATCH);
1574 				if (error != 0)
1575 					return (error);
1576 				return (EAGAIN);
1577 			}
1578 			error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd);
1579 			VOP_UNLOCK(vp, 0);
1580 			vput(nd.ni_dvp);
1581 			vn_finished_write(mp);
1582 			NDFREE(&nd, NDF_ONLY_PNBUF);
1583 		} else {
1584 			vput(nd.ni_dvp);
1585 			NDFREE(&nd, NDF_ONLY_PNBUF);
1586 			vrele(vp);
1587 			return (EAGAIN);
1588 		}
1589 	}
1590 	vrele(vp);
1591 	return (error);
1592 }
1593 
1594 /*
1595  * Make a symbolic link.
1596  */
1597 #ifndef _SYS_SYSPROTO_H_
1598 struct symlink_args {
1599 	char	*path;
1600 	char	*link;
1601 };
1602 #endif
1603 int
sys_symlink(struct thread * td,struct symlink_args * uap)1604 sys_symlink(struct thread *td, struct symlink_args *uap)
1605 {
1606 
1607 	return (kern_symlinkat(td, uap->path, AT_FDCWD, uap->link,
1608 	    UIO_USERSPACE));
1609 }
1610 
1611 #ifndef _SYS_SYSPROTO_H_
1612 struct symlinkat_args {
1613 	char	*path;
1614 	int	fd;
1615 	char	*path2;
1616 };
1617 #endif
1618 int
sys_symlinkat(struct thread * td,struct symlinkat_args * uap)1619 sys_symlinkat(struct thread *td, struct symlinkat_args *uap)
1620 {
1621 
1622 	return (kern_symlinkat(td, uap->path1, uap->fd, uap->path2,
1623 	    UIO_USERSPACE));
1624 }
1625 
1626 int
kern_symlinkat(struct thread * td,char * path1,int fd,char * path2,enum uio_seg segflg)1627 kern_symlinkat(struct thread *td, char *path1, int fd, char *path2,
1628     enum uio_seg segflg)
1629 {
1630 	struct mount *mp;
1631 	struct vattr vattr;
1632 	char *syspath;
1633 	struct nameidata nd;
1634 	int error;
1635 
1636 	if (segflg == UIO_SYSSPACE) {
1637 		syspath = path1;
1638 	} else {
1639 		syspath = uma_zalloc(namei_zone, M_WAITOK);
1640 		if ((error = copyinstr(path1, syspath, MAXPATHLEN, NULL)) != 0)
1641 			goto out;
1642 	}
1643 	AUDIT_ARG_TEXT(syspath);
1644 restart:
1645 	bwillwrite();
1646 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1 |
1647 	    NOCACHE, segflg, path2, fd, &cap_symlinkat_rights,
1648 	    td);
1649 	if ((error = namei(&nd)) != 0)
1650 		goto out;
1651 	if (nd.ni_vp) {
1652 		NDFREE(&nd, NDF_ONLY_PNBUF);
1653 		if (nd.ni_vp == nd.ni_dvp)
1654 			vrele(nd.ni_dvp);
1655 		else
1656 			vput(nd.ni_dvp);
1657 		vrele(nd.ni_vp);
1658 		error = EEXIST;
1659 		goto out;
1660 	}
1661 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1662 		NDFREE(&nd, NDF_ONLY_PNBUF);
1663 		vput(nd.ni_dvp);
1664 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1665 			goto out;
1666 		goto restart;
1667 	}
1668 	VATTR_NULL(&vattr);
1669 	vattr.va_mode = ACCESSPERMS &~ td->td_proc->p_fd->fd_cmask;
1670 #ifdef MAC
1671 	vattr.va_type = VLNK;
1672 	error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
1673 	    &vattr);
1674 	if (error != 0)
1675 		goto out2;
1676 #endif
1677 	error = VOP_SYMLINK(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr, syspath);
1678 	if (error == 0)
1679 		vput(nd.ni_vp);
1680 #ifdef MAC
1681 out2:
1682 #endif
1683 	NDFREE(&nd, NDF_ONLY_PNBUF);
1684 	vput(nd.ni_dvp);
1685 	vn_finished_write(mp);
1686 out:
1687 	if (segflg != UIO_SYSSPACE)
1688 		uma_zfree(namei_zone, syspath);
1689 	return (error);
1690 }
1691 
1692 /*
1693  * Delete a whiteout from the filesystem.
1694  */
1695 #ifndef _SYS_SYSPROTO_H_
1696 struct undelete_args {
1697 	char *path;
1698 };
1699 #endif
1700 int
sys_undelete(struct thread * td,struct undelete_args * uap)1701 sys_undelete(struct thread *td, struct undelete_args *uap)
1702 {
1703 	struct mount *mp;
1704 	struct nameidata nd;
1705 	int error;
1706 
1707 restart:
1708 	bwillwrite();
1709 	NDINIT(&nd, DELETE, LOCKPARENT | DOWHITEOUT | AUDITVNODE1,
1710 	    UIO_USERSPACE, uap->path, td);
1711 	error = namei(&nd);
1712 	if (error != 0)
1713 		return (error);
1714 
1715 	if (nd.ni_vp != NULLVP || !(nd.ni_cnd.cn_flags & ISWHITEOUT)) {
1716 		NDFREE(&nd, NDF_ONLY_PNBUF);
1717 		if (nd.ni_vp == nd.ni_dvp)
1718 			vrele(nd.ni_dvp);
1719 		else
1720 			vput(nd.ni_dvp);
1721 		if (nd.ni_vp)
1722 			vrele(nd.ni_vp);
1723 		return (EEXIST);
1724 	}
1725 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1726 		NDFREE(&nd, NDF_ONLY_PNBUF);
1727 		vput(nd.ni_dvp);
1728 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
1729 			return (error);
1730 		goto restart;
1731 	}
1732 	error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, DELETE);
1733 	NDFREE(&nd, NDF_ONLY_PNBUF);
1734 	vput(nd.ni_dvp);
1735 	vn_finished_write(mp);
1736 	return (error);
1737 }
1738 
1739 /*
1740  * Delete a name from the filesystem.
1741  */
1742 #ifndef _SYS_SYSPROTO_H_
1743 struct unlink_args {
1744 	char	*path;
1745 };
1746 #endif
1747 int
sys_unlink(struct thread * td,struct unlink_args * uap)1748 sys_unlink(struct thread *td, struct unlink_args *uap)
1749 {
1750 
1751 	return (kern_unlinkat(td, AT_FDCWD, uap->path, UIO_USERSPACE, 0));
1752 }
1753 
1754 #ifndef _SYS_SYSPROTO_H_
1755 struct unlinkat_args {
1756 	int	fd;
1757 	char	*path;
1758 	int	flag;
1759 };
1760 #endif
1761 int
sys_unlinkat(struct thread * td,struct unlinkat_args * uap)1762 sys_unlinkat(struct thread *td, struct unlinkat_args *uap)
1763 {
1764 	int flag = uap->flag;
1765 	int fd = uap->fd;
1766 	char *path = uap->path;
1767 
1768 	if (flag & ~AT_REMOVEDIR)
1769 		return (EINVAL);
1770 
1771 	if (flag & AT_REMOVEDIR)
1772 		return (kern_rmdirat(td, fd, path, UIO_USERSPACE));
1773 	else
1774 		return (kern_unlinkat(td, fd, path, UIO_USERSPACE, 0));
1775 }
1776 
1777 int
kern_unlinkat(struct thread * td,int fd,char * path,enum uio_seg pathseg,ino_t oldinum)1778 kern_unlinkat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1779     ino_t oldinum)
1780 {
1781 	struct mount *mp;
1782 	struct vnode *vp;
1783 	struct nameidata nd;
1784 	struct stat sb;
1785 	int error;
1786 
1787 restart:
1788 	bwillwrite();
1789 	NDINIT_ATRIGHTS(&nd, DELETE, LOCKPARENT | LOCKLEAF | AUDITVNODE1,
1790 	    pathseg, path, fd, &cap_unlinkat_rights, td);
1791 	if ((error = namei(&nd)) != 0)
1792 		return (error == EINVAL ? EPERM : error);
1793 	vp = nd.ni_vp;
1794 	if (vp->v_type == VDIR && oldinum == 0) {
1795 		error = EPERM;		/* POSIX */
1796 	} else if (oldinum != 0 &&
1797 		  ((error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td)) == 0) &&
1798 		  sb.st_ino != oldinum) {
1799 			error = EIDRM;	/* Identifier removed */
1800 	} else {
1801 		/*
1802 		 * The root of a mounted filesystem cannot be deleted.
1803 		 *
1804 		 * XXX: can this only be a VDIR case?
1805 		 */
1806 		if (vp->v_vflag & VV_ROOT)
1807 			error = EBUSY;
1808 	}
1809 	if (error == 0) {
1810 		if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1811 			NDFREE(&nd, NDF_ONLY_PNBUF);
1812 			vput(nd.ni_dvp);
1813 			if (vp == nd.ni_dvp)
1814 				vrele(vp);
1815 			else
1816 				vput(vp);
1817 			if ((error = vn_start_write(NULL, &mp,
1818 			    V_XSLEEP | PCATCH)) != 0)
1819 				return (error);
1820 			goto restart;
1821 		}
1822 #ifdef MAC
1823 		error = mac_vnode_check_unlink(td->td_ucred, nd.ni_dvp, vp,
1824 		    &nd.ni_cnd);
1825 		if (error != 0)
1826 			goto out;
1827 #endif
1828 		vfs_notify_upper(vp, VFS_NOTIFY_UPPER_UNLINK);
1829 		error = VOP_REMOVE(nd.ni_dvp, vp, &nd.ni_cnd);
1830 #ifdef MAC
1831 out:
1832 #endif
1833 		vn_finished_write(mp);
1834 	}
1835 	NDFREE(&nd, NDF_ONLY_PNBUF);
1836 	vput(nd.ni_dvp);
1837 	if (vp == nd.ni_dvp)
1838 		vrele(vp);
1839 	else
1840 		vput(vp);
1841 	return (error);
1842 }
1843 
1844 /*
1845  * Reposition read/write file offset.
1846  */
1847 #ifndef _SYS_SYSPROTO_H_
1848 struct lseek_args {
1849 	int	fd;
1850 	int	pad;
1851 	off_t	offset;
1852 	int	whence;
1853 };
1854 #endif
1855 int
sys_lseek(struct thread * td,struct lseek_args * uap)1856 sys_lseek(struct thread *td, struct lseek_args *uap)
1857 {
1858 
1859 	return (kern_lseek(td, uap->fd, uap->offset, uap->whence));
1860 }
1861 
1862 int
kern_lseek(struct thread * td,int fd,off_t offset,int whence)1863 kern_lseek(struct thread *td, int fd, off_t offset, int whence)
1864 {
1865 	struct file *fp;
1866 	int error;
1867 
1868 	AUDIT_ARG_FD(fd);
1869 	error = fget(td, fd, &cap_seek_rights, &fp);
1870 	if (error != 0)
1871 		return (error);
1872 	error = (fp->f_ops->fo_flags & DFLAG_SEEKABLE) != 0 ?
1873 	    fo_seek(fp, offset, whence, td) : ESPIPE;
1874 	fdrop(fp, td);
1875 	return (error);
1876 }
1877 
1878 #if defined(COMPAT_43)
1879 /*
1880  * Reposition read/write file offset.
1881  */
1882 #ifndef _SYS_SYSPROTO_H_
1883 struct olseek_args {
1884 	int	fd;
1885 	long	offset;
1886 	int	whence;
1887 };
1888 #endif
1889 int
olseek(struct thread * td,struct olseek_args * uap)1890 olseek(struct thread *td, struct olseek_args *uap)
1891 {
1892 
1893 	return (kern_lseek(td, uap->fd, uap->offset, uap->whence));
1894 }
1895 #endif /* COMPAT_43 */
1896 
1897 #if defined(COMPAT_FREEBSD6)
1898 /* Version with the 'pad' argument */
1899 int
freebsd6_lseek(struct thread * td,struct freebsd6_lseek_args * uap)1900 freebsd6_lseek(struct thread *td, struct freebsd6_lseek_args *uap)
1901 {
1902 
1903 	return (kern_lseek(td, uap->fd, uap->offset, uap->whence));
1904 }
1905 #endif
1906 
1907 /*
1908  * Check access permissions using passed credentials.
1909  */
1910 static int
vn_access(struct vnode * vp,int user_flags,struct ucred * cred,struct thread * td)1911 vn_access(struct vnode *vp, int user_flags, struct ucred *cred,
1912      struct thread *td)
1913 {
1914 	accmode_t accmode;
1915 	int error;
1916 
1917 	/* Flags == 0 means only check for existence. */
1918 	if (user_flags == 0)
1919 		return (0);
1920 
1921 	accmode = 0;
1922 	if (user_flags & R_OK)
1923 		accmode |= VREAD;
1924 	if (user_flags & W_OK)
1925 		accmode |= VWRITE;
1926 	if (user_flags & X_OK)
1927 		accmode |= VEXEC;
1928 #ifdef MAC
1929 	error = mac_vnode_check_access(cred, vp, accmode);
1930 	if (error != 0)
1931 		return (error);
1932 #endif
1933 	if ((accmode & VWRITE) == 0 || (error = vn_writechk(vp)) == 0)
1934 		error = VOP_ACCESS(vp, accmode, cred, td);
1935 	return (error);
1936 }
1937 
1938 /*
1939  * Check access permissions using "real" credentials.
1940  */
1941 #ifndef _SYS_SYSPROTO_H_
1942 struct access_args {
1943 	char	*path;
1944 	int	amode;
1945 };
1946 #endif
1947 int
sys_access(struct thread * td,struct access_args * uap)1948 sys_access(struct thread *td, struct access_args *uap)
1949 {
1950 
1951 	return (kern_accessat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
1952 	    0, uap->amode));
1953 }
1954 
1955 #ifndef _SYS_SYSPROTO_H_
1956 struct faccessat_args {
1957 	int	dirfd;
1958 	char	*path;
1959 	int	amode;
1960 	int	flag;
1961 }
1962 #endif
1963 int
sys_faccessat(struct thread * td,struct faccessat_args * uap)1964 sys_faccessat(struct thread *td, struct faccessat_args *uap)
1965 {
1966 
1967 	return (kern_accessat(td, uap->fd, uap->path, UIO_USERSPACE, uap->flag,
1968 	    uap->amode));
1969 }
1970 
1971 int
kern_accessat(struct thread * td,int fd,char * path,enum uio_seg pathseg,int flag,int amode)1972 kern_accessat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
1973     int flag, int amode)
1974 {
1975 	struct ucred *cred, *usecred;
1976 	struct vnode *vp;
1977 	struct nameidata nd;
1978 	int error;
1979 
1980 	if (flag & ~AT_EACCESS)
1981 		return (EINVAL);
1982 	if (amode != F_OK && (amode & ~(R_OK | W_OK | X_OK)) != 0)
1983 		return (EINVAL);
1984 
1985 	/*
1986 	 * Create and modify a temporary credential instead of one that
1987 	 * is potentially shared (if we need one).
1988 	 */
1989 	cred = td->td_ucred;
1990 	if ((flag & AT_EACCESS) == 0 &&
1991 	    ((cred->cr_uid != cred->cr_ruid ||
1992 	    cred->cr_rgid != cred->cr_groups[0]))) {
1993 		usecred = crdup(cred);
1994 		usecred->cr_uid = cred->cr_ruid;
1995 		usecred->cr_groups[0] = cred->cr_rgid;
1996 		td->td_ucred = usecred;
1997 	} else
1998 		usecred = cred;
1999 	AUDIT_ARG_VALUE(amode);
2000 	NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF |
2001 	    AUDITVNODE1, pathseg, path, fd, &cap_fstat_rights,
2002 	    td);
2003 	if ((error = namei(&nd)) != 0)
2004 		goto out;
2005 	vp = nd.ni_vp;
2006 
2007 	error = vn_access(vp, amode, usecred, td);
2008 	NDFREE(&nd, NDF_ONLY_PNBUF);
2009 	vput(vp);
2010 out:
2011 	if (usecred != cred) {
2012 		td->td_ucred = cred;
2013 		crfree(usecred);
2014 	}
2015 	return (error);
2016 }
2017 
2018 /*
2019  * Check access permissions using "effective" credentials.
2020  */
2021 #ifndef _SYS_SYSPROTO_H_
2022 struct eaccess_args {
2023 	char	*path;
2024 	int	amode;
2025 };
2026 #endif
2027 int
sys_eaccess(struct thread * td,struct eaccess_args * uap)2028 sys_eaccess(struct thread *td, struct eaccess_args *uap)
2029 {
2030 
2031 	return (kern_accessat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2032 	    AT_EACCESS, uap->amode));
2033 }
2034 
2035 #if defined(COMPAT_43)
2036 /*
2037  * Get file status; this version follows links.
2038  */
2039 #ifndef _SYS_SYSPROTO_H_
2040 struct ostat_args {
2041 	char	*path;
2042 	struct ostat *ub;
2043 };
2044 #endif
2045 int
ostat(struct thread * td,struct ostat_args * uap)2046 ostat(struct thread *td, struct ostat_args *uap)
2047 {
2048 	struct stat sb;
2049 	struct ostat osb;
2050 	int error;
2051 
2052 	error = kern_statat(td, 0, AT_FDCWD, uap->path, UIO_USERSPACE,
2053 	    &sb, NULL);
2054 	if (error != 0)
2055 		return (error);
2056 	cvtstat(&sb, &osb);
2057 	return (copyout(&osb, uap->ub, sizeof (osb)));
2058 }
2059 
2060 /*
2061  * Get file status; this version does not follow links.
2062  */
2063 #ifndef _SYS_SYSPROTO_H_
2064 struct olstat_args {
2065 	char	*path;
2066 	struct ostat *ub;
2067 };
2068 #endif
2069 int
olstat(struct thread * td,struct olstat_args * uap)2070 olstat(struct thread *td, struct olstat_args *uap)
2071 {
2072 	struct stat sb;
2073 	struct ostat osb;
2074 	int error;
2075 
2076 	error = kern_statat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, uap->path,
2077 	    UIO_USERSPACE, &sb, NULL);
2078 	if (error != 0)
2079 		return (error);
2080 	cvtstat(&sb, &osb);
2081 	return (copyout(&osb, uap->ub, sizeof (osb)));
2082 }
2083 
2084 /*
2085  * Convert from an old to a new stat structure.
2086  * XXX: many values are blindly truncated.
2087  */
2088 void
cvtstat(struct stat * st,struct ostat * ost)2089 cvtstat(struct stat *st, struct ostat *ost)
2090 {
2091 
2092 	bzero(ost, sizeof(*ost));
2093 	ost->st_dev = st->st_dev;
2094 	ost->st_ino = st->st_ino;
2095 	ost->st_mode = st->st_mode;
2096 	ost->st_nlink = st->st_nlink;
2097 	ost->st_uid = st->st_uid;
2098 	ost->st_gid = st->st_gid;
2099 	ost->st_rdev = st->st_rdev;
2100 	ost->st_size = MIN(st->st_size, INT32_MAX);
2101 	ost->st_atim = st->st_atim;
2102 	ost->st_mtim = st->st_mtim;
2103 	ost->st_ctim = st->st_ctim;
2104 	ost->st_blksize = st->st_blksize;
2105 	ost->st_blocks = st->st_blocks;
2106 	ost->st_flags = st->st_flags;
2107 	ost->st_gen = st->st_gen;
2108 }
2109 #endif /* COMPAT_43 */
2110 
2111 #if defined(COMPAT_43) || defined(COMPAT_FREEBSD11)
2112 int ino64_trunc_error;
2113 SYSCTL_INT(_vfs, OID_AUTO, ino64_trunc_error, CTLFLAG_RW,
2114     &ino64_trunc_error, 0,
2115     "Error on truncation of device, file or inode number, or link count");
2116 
2117 int
freebsd11_cvtstat(struct stat * st,struct freebsd11_stat * ost)2118 freebsd11_cvtstat(struct stat *st, struct freebsd11_stat *ost)
2119 {
2120 
2121 	ost->st_dev = st->st_dev;
2122 	if (ost->st_dev != st->st_dev) {
2123 		switch (ino64_trunc_error) {
2124 		default:
2125 			/*
2126 			 * Since dev_t is almost raw, don't clamp to the
2127 			 * maximum for case 2, but ignore the error.
2128 			 */
2129 			break;
2130 		case 1:
2131 			return (EOVERFLOW);
2132 		}
2133 	}
2134 	ost->st_ino = st->st_ino;
2135 	if (ost->st_ino != st->st_ino) {
2136 		switch (ino64_trunc_error) {
2137 		default:
2138 		case 0:
2139 			break;
2140 		case 1:
2141 			return (EOVERFLOW);
2142 		case 2:
2143 			ost->st_ino = UINT32_MAX;
2144 			break;
2145 		}
2146 	}
2147 	ost->st_mode = st->st_mode;
2148 	ost->st_nlink = st->st_nlink;
2149 	if (ost->st_nlink != st->st_nlink) {
2150 		switch (ino64_trunc_error) {
2151 		default:
2152 		case 0:
2153 			break;
2154 		case 1:
2155 			return (EOVERFLOW);
2156 		case 2:
2157 			ost->st_nlink = UINT16_MAX;
2158 			break;
2159 		}
2160 	}
2161 	ost->st_uid = st->st_uid;
2162 	ost->st_gid = st->st_gid;
2163 	ost->st_rdev = st->st_rdev;
2164 	if (ost->st_rdev != st->st_rdev) {
2165 		switch (ino64_trunc_error) {
2166 		default:
2167 			break;
2168 		case 1:
2169 			return (EOVERFLOW);
2170 		}
2171 	}
2172 	ost->st_atim = st->st_atim;
2173 	ost->st_mtim = st->st_mtim;
2174 	ost->st_ctim = st->st_ctim;
2175 	ost->st_size = st->st_size;
2176 	ost->st_blocks = st->st_blocks;
2177 	ost->st_blksize = st->st_blksize;
2178 	ost->st_flags = st->st_flags;
2179 	ost->st_gen = st->st_gen;
2180 	ost->st_lspare = 0;
2181 	ost->st_birthtim = st->st_birthtim;
2182 	bzero((char *)&ost->st_birthtim + sizeof(ost->st_birthtim),
2183 	    sizeof(*ost) - offsetof(struct freebsd11_stat,
2184 	    st_birthtim) - sizeof(ost->st_birthtim));
2185 	return (0);
2186 }
2187 
2188 int
freebsd11_stat(struct thread * td,struct freebsd11_stat_args * uap)2189 freebsd11_stat(struct thread *td, struct freebsd11_stat_args* uap)
2190 {
2191 	struct stat sb;
2192 	struct freebsd11_stat osb;
2193 	int error;
2194 
2195 	error = kern_statat(td, 0, AT_FDCWD, uap->path, UIO_USERSPACE,
2196 	    &sb, NULL);
2197 	if (error != 0)
2198 		return (error);
2199 	error = freebsd11_cvtstat(&sb, &osb);
2200 	if (error == 0)
2201 		error = copyout(&osb, uap->ub, sizeof(osb));
2202 	return (error);
2203 }
2204 
2205 int
freebsd11_lstat(struct thread * td,struct freebsd11_lstat_args * uap)2206 freebsd11_lstat(struct thread *td, struct freebsd11_lstat_args* uap)
2207 {
2208 	struct stat sb;
2209 	struct freebsd11_stat osb;
2210 	int error;
2211 
2212 	error = kern_statat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, uap->path,
2213 	    UIO_USERSPACE, &sb, NULL);
2214 	if (error != 0)
2215 		return (error);
2216 	error = freebsd11_cvtstat(&sb, &osb);
2217 	if (error == 0)
2218 		error = copyout(&osb, uap->ub, sizeof(osb));
2219 	return (error);
2220 }
2221 
2222 int
freebsd11_fhstat(struct thread * td,struct freebsd11_fhstat_args * uap)2223 freebsd11_fhstat(struct thread *td, struct freebsd11_fhstat_args* uap)
2224 {
2225 	struct fhandle fh;
2226 	struct stat sb;
2227 	struct freebsd11_stat osb;
2228 	int error;
2229 
2230 	error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
2231 	if (error != 0)
2232 		return (error);
2233 	error = kern_fhstat(td, fh, &sb);
2234 	if (error != 0)
2235 		return (error);
2236 	error = freebsd11_cvtstat(&sb, &osb);
2237 	if (error == 0)
2238 		error = copyout(&osb, uap->sb, sizeof(osb));
2239 	return (error);
2240 }
2241 
2242 int
freebsd11_fstatat(struct thread * td,struct freebsd11_fstatat_args * uap)2243 freebsd11_fstatat(struct thread *td, struct freebsd11_fstatat_args* uap)
2244 {
2245 	struct stat sb;
2246 	struct freebsd11_stat osb;
2247 	int error;
2248 
2249 	error = kern_statat(td, uap->flag, uap->fd, uap->path,
2250 	    UIO_USERSPACE, &sb, NULL);
2251 	if (error != 0)
2252 		return (error);
2253 	error = freebsd11_cvtstat(&sb, &osb);
2254 	if (error == 0)
2255 		error = copyout(&osb, uap->buf, sizeof(osb));
2256 	return (error);
2257 }
2258 #endif	/* COMPAT_FREEBSD11 */
2259 
2260 /*
2261  * Get file status
2262  */
2263 #ifndef _SYS_SYSPROTO_H_
2264 struct fstatat_args {
2265 	int	fd;
2266 	char	*path;
2267 	struct stat	*buf;
2268 	int	flag;
2269 }
2270 #endif
2271 int
sys_fstatat(struct thread * td,struct fstatat_args * uap)2272 sys_fstatat(struct thread *td, struct fstatat_args *uap)
2273 {
2274 	struct stat sb;
2275 	int error;
2276 
2277 	error = kern_statat(td, uap->flag, uap->fd, uap->path,
2278 	    UIO_USERSPACE, &sb, NULL);
2279 	if (error == 0)
2280 		error = copyout(&sb, uap->buf, sizeof (sb));
2281 	return (error);
2282 }
2283 
2284 int
kern_statat(struct thread * td,int flag,int fd,char * path,enum uio_seg pathseg,struct stat * sbp,void (* hook)(struct vnode * vp,struct stat * sbp))2285 kern_statat(struct thread *td, int flag, int fd, char *path,
2286     enum uio_seg pathseg, struct stat *sbp,
2287     void (*hook)(struct vnode *vp, struct stat *sbp))
2288 {
2289 	struct nameidata nd;
2290 	struct stat sb;
2291 	int error;
2292 
2293 	if (flag & ~AT_SYMLINK_NOFOLLOW)
2294 		return (EINVAL);
2295 
2296 	NDINIT_ATRIGHTS(&nd, LOOKUP, ((flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW :
2297 	    FOLLOW) | LOCKSHARED | LOCKLEAF | AUDITVNODE1, pathseg, path, fd,
2298 	    &cap_fstat_rights, td);
2299 
2300 	if ((error = namei(&nd)) != 0)
2301 		return (error);
2302 	error = vn_stat(nd.ni_vp, &sb, td->td_ucred, NOCRED, td);
2303 	if (error == 0) {
2304 		SDT_PROBE2(vfs, , stat, mode, path, sb.st_mode);
2305 		if (S_ISREG(sb.st_mode))
2306 			SDT_PROBE2(vfs, , stat, reg, path, pathseg);
2307 		if (__predict_false(hook != NULL))
2308 			hook(nd.ni_vp, &sb);
2309 	}
2310 	NDFREE(&nd, NDF_ONLY_PNBUF);
2311 	vput(nd.ni_vp);
2312 	if (error != 0)
2313 		return (error);
2314 #ifdef __STAT_TIME_T_EXT
2315 	sb.st_atim_ext = 0;
2316 	sb.st_mtim_ext = 0;
2317 	sb.st_ctim_ext = 0;
2318 	sb.st_btim_ext = 0;
2319 #endif
2320 	*sbp = sb;
2321 #ifdef KTRACE
2322 	if (KTRPOINT(td, KTR_STRUCT))
2323 		ktrstat(&sb);
2324 #endif
2325 	return (0);
2326 }
2327 
2328 #if defined(COMPAT_FREEBSD11)
2329 /*
2330  * Implementation of the NetBSD [l]stat() functions.
2331  */
2332 void
freebsd11_cvtnstat(struct stat * sb,struct nstat * nsb)2333 freebsd11_cvtnstat(struct stat *sb, struct nstat *nsb)
2334 {
2335 
2336 	bzero(nsb, sizeof(*nsb));
2337 	nsb->st_dev = sb->st_dev;
2338 	nsb->st_ino = sb->st_ino;
2339 	nsb->st_mode = sb->st_mode;
2340 	nsb->st_nlink = sb->st_nlink;
2341 	nsb->st_uid = sb->st_uid;
2342 	nsb->st_gid = sb->st_gid;
2343 	nsb->st_rdev = sb->st_rdev;
2344 	nsb->st_atim = sb->st_atim;
2345 	nsb->st_mtim = sb->st_mtim;
2346 	nsb->st_ctim = sb->st_ctim;
2347 	nsb->st_size = sb->st_size;
2348 	nsb->st_blocks = sb->st_blocks;
2349 	nsb->st_blksize = sb->st_blksize;
2350 	nsb->st_flags = sb->st_flags;
2351 	nsb->st_gen = sb->st_gen;
2352 	nsb->st_birthtim = sb->st_birthtim;
2353 }
2354 
2355 #ifndef _SYS_SYSPROTO_H_
2356 struct freebsd11_nstat_args {
2357 	char	*path;
2358 	struct nstat *ub;
2359 };
2360 #endif
2361 int
freebsd11_nstat(struct thread * td,struct freebsd11_nstat_args * uap)2362 freebsd11_nstat(struct thread *td, struct freebsd11_nstat_args *uap)
2363 {
2364 	struct stat sb;
2365 	struct nstat nsb;
2366 	int error;
2367 
2368 	error = kern_statat(td, 0, AT_FDCWD, uap->path, UIO_USERSPACE,
2369 	    &sb, NULL);
2370 	if (error != 0)
2371 		return (error);
2372 	freebsd11_cvtnstat(&sb, &nsb);
2373 	return (copyout(&nsb, uap->ub, sizeof (nsb)));
2374 }
2375 
2376 /*
2377  * NetBSD lstat.  Get file status; this version does not follow links.
2378  */
2379 #ifndef _SYS_SYSPROTO_H_
2380 struct freebsd11_nlstat_args {
2381 	char	*path;
2382 	struct nstat *ub;
2383 };
2384 #endif
2385 int
freebsd11_nlstat(struct thread * td,struct freebsd11_nlstat_args * uap)2386 freebsd11_nlstat(struct thread *td, struct freebsd11_nlstat_args *uap)
2387 {
2388 	struct stat sb;
2389 	struct nstat nsb;
2390 	int error;
2391 
2392 	error = kern_statat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, uap->path,
2393 	    UIO_USERSPACE, &sb, NULL);
2394 	if (error != 0)
2395 		return (error);
2396 	freebsd11_cvtnstat(&sb, &nsb);
2397 	return (copyout(&nsb, uap->ub, sizeof (nsb)));
2398 }
2399 #endif /* COMPAT_FREEBSD11 */
2400 
2401 /*
2402  * Get configurable pathname variables.
2403  */
2404 #ifndef _SYS_SYSPROTO_H_
2405 struct pathconf_args {
2406 	char	*path;
2407 	int	name;
2408 };
2409 #endif
2410 int
sys_pathconf(struct thread * td,struct pathconf_args * uap)2411 sys_pathconf(struct thread *td, struct pathconf_args *uap)
2412 {
2413 	long value;
2414 	int error;
2415 
2416 	error = kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name, FOLLOW,
2417 	    &value);
2418 	if (error == 0)
2419 		td->td_retval[0] = value;
2420 	return (error);
2421 }
2422 
2423 #ifndef _SYS_SYSPROTO_H_
2424 struct lpathconf_args {
2425 	char	*path;
2426 	int	name;
2427 };
2428 #endif
2429 int
sys_lpathconf(struct thread * td,struct lpathconf_args * uap)2430 sys_lpathconf(struct thread *td, struct lpathconf_args *uap)
2431 {
2432 	long value;
2433 	int error;
2434 
2435 	error = kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name,
2436 	    NOFOLLOW, &value);
2437 	if (error == 0)
2438 		td->td_retval[0] = value;
2439 	return (error);
2440 }
2441 
2442 int
kern_pathconf(struct thread * td,char * path,enum uio_seg pathseg,int name,u_long flags,long * valuep)2443 kern_pathconf(struct thread *td, char *path, enum uio_seg pathseg, int name,
2444     u_long flags, long *valuep)
2445 {
2446 	struct nameidata nd;
2447 	int error;
2448 
2449 	NDINIT(&nd, LOOKUP, LOCKSHARED | LOCKLEAF | AUDITVNODE1 | flags,
2450 	    pathseg, path, td);
2451 	if ((error = namei(&nd)) != 0)
2452 		return (error);
2453 	NDFREE(&nd, NDF_ONLY_PNBUF);
2454 
2455 	error = VOP_PATHCONF(nd.ni_vp, name, valuep);
2456 	vput(nd.ni_vp);
2457 	return (error);
2458 }
2459 
2460 /*
2461  * Return target name of a symbolic link.
2462  */
2463 #ifndef _SYS_SYSPROTO_H_
2464 struct readlink_args {
2465 	char	*path;
2466 	char	*buf;
2467 	size_t	count;
2468 };
2469 #endif
2470 int
sys_readlink(struct thread * td,struct readlink_args * uap)2471 sys_readlink(struct thread *td, struct readlink_args *uap)
2472 {
2473 
2474 	return (kern_readlinkat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2475 	    uap->buf, UIO_USERSPACE, uap->count));
2476 }
2477 #ifndef _SYS_SYSPROTO_H_
2478 struct readlinkat_args {
2479 	int	fd;
2480 	char	*path;
2481 	char	*buf;
2482 	size_t	bufsize;
2483 };
2484 #endif
2485 int
sys_readlinkat(struct thread * td,struct readlinkat_args * uap)2486 sys_readlinkat(struct thread *td, struct readlinkat_args *uap)
2487 {
2488 
2489 	return (kern_readlinkat(td, uap->fd, uap->path, UIO_USERSPACE,
2490 	    uap->buf, UIO_USERSPACE, uap->bufsize));
2491 }
2492 
2493 int
kern_readlinkat(struct thread * td,int fd,char * path,enum uio_seg pathseg,char * buf,enum uio_seg bufseg,size_t count)2494 kern_readlinkat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2495     char *buf, enum uio_seg bufseg, size_t count)
2496 {
2497 	struct vnode *vp;
2498 	struct nameidata nd;
2499 	int error;
2500 
2501 	if (count > IOSIZE_MAX)
2502 		return (EINVAL);
2503 
2504 	NDINIT_AT(&nd, LOOKUP, NOFOLLOW | LOCKSHARED | LOCKLEAF | AUDITVNODE1,
2505 	    pathseg, path, fd, td);
2506 
2507 	if ((error = namei(&nd)) != 0)
2508 		return (error);
2509 	NDFREE(&nd, NDF_ONLY_PNBUF);
2510 	vp = nd.ni_vp;
2511 
2512 	error = kern_readlink_vp(vp, buf, bufseg, count, td);
2513 	vput(vp);
2514 
2515 	return (error);
2516 }
2517 
2518 /*
2519  * Helper function to readlink from a vnode
2520  */
2521 static int
kern_readlink_vp(struct vnode * vp,char * buf,enum uio_seg bufseg,size_t count,struct thread * td)2522 kern_readlink_vp(struct vnode *vp, char *buf, enum uio_seg bufseg, size_t count,
2523     struct thread *td)
2524 {
2525 	struct iovec aiov;
2526 	struct uio auio;
2527 	int error;
2528 
2529 	ASSERT_VOP_LOCKED(vp, "kern_readlink_vp(): vp not locked");
2530 #ifdef MAC
2531 	error = mac_vnode_check_readlink(td->td_ucred, vp);
2532 	if (error != 0)
2533 		return (error);
2534 #endif
2535 	if (vp->v_type != VLNK && (vp->v_vflag & VV_READLINK) == 0)
2536 		return (EINVAL);
2537 
2538 	aiov.iov_base = buf;
2539 	aiov.iov_len = count;
2540 	auio.uio_iov = &aiov;
2541 	auio.uio_iovcnt = 1;
2542 	auio.uio_offset = 0;
2543 	auio.uio_rw = UIO_READ;
2544 	auio.uio_segflg = bufseg;
2545 	auio.uio_td = td;
2546 	auio.uio_resid = count;
2547 	error = VOP_READLINK(vp, &auio, td->td_ucred);
2548 	td->td_retval[0] = count - auio.uio_resid;
2549 	return (error);
2550 }
2551 
2552 /*
2553  * Common implementation code for chflags() and fchflags().
2554  */
2555 static int
setfflags(struct thread * td,struct vnode * vp,u_long flags)2556 setfflags(struct thread *td, struct vnode *vp, u_long flags)
2557 {
2558 	struct mount *mp;
2559 	struct vattr vattr;
2560 	int error;
2561 
2562 	/* We can't support the value matching VNOVAL. */
2563 	if (flags == VNOVAL)
2564 		return (EOPNOTSUPP);
2565 
2566 	/*
2567 	 * Prevent non-root users from setting flags on devices.  When
2568 	 * a device is reused, users can retain ownership of the device
2569 	 * if they are allowed to set flags and programs assume that
2570 	 * chown can't fail when done as root.
2571 	 */
2572 	if (vp->v_type == VCHR || vp->v_type == VBLK) {
2573 		error = priv_check(td, PRIV_VFS_CHFLAGS_DEV);
2574 		if (error != 0)
2575 			return (error);
2576 	}
2577 
2578 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
2579 		return (error);
2580 	VATTR_NULL(&vattr);
2581 	vattr.va_flags = flags;
2582 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2583 #ifdef MAC
2584 	error = mac_vnode_check_setflags(td->td_ucred, vp, vattr.va_flags);
2585 	if (error == 0)
2586 #endif
2587 		error = VOP_SETATTR(vp, &vattr, td->td_ucred);
2588 	VOP_UNLOCK(vp, 0);
2589 	vn_finished_write(mp);
2590 	return (error);
2591 }
2592 
2593 /*
2594  * Change flags of a file given a path name.
2595  */
2596 #ifndef _SYS_SYSPROTO_H_
2597 struct chflags_args {
2598 	const char *path;
2599 	u_long	flags;
2600 };
2601 #endif
2602 int
sys_chflags(struct thread * td,struct chflags_args * uap)2603 sys_chflags(struct thread *td, struct chflags_args *uap)
2604 {
2605 
2606 	return (kern_chflagsat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2607 	    uap->flags, 0));
2608 }
2609 
2610 #ifndef _SYS_SYSPROTO_H_
2611 struct chflagsat_args {
2612 	int	fd;
2613 	const char *path;
2614 	u_long	flags;
2615 	int	atflag;
2616 }
2617 #endif
2618 int
sys_chflagsat(struct thread * td,struct chflagsat_args * uap)2619 sys_chflagsat(struct thread *td, struct chflagsat_args *uap)
2620 {
2621 	int fd = uap->fd;
2622 	const char *path = uap->path;
2623 	u_long flags = uap->flags;
2624 	int atflag = uap->atflag;
2625 
2626 	if (atflag & ~AT_SYMLINK_NOFOLLOW)
2627 		return (EINVAL);
2628 
2629 	return (kern_chflagsat(td, fd, path, UIO_USERSPACE, flags, atflag));
2630 }
2631 
2632 /*
2633  * Same as chflags() but doesn't follow symlinks.
2634  */
2635 #ifndef _SYS_SYSPROTO_H_
2636 struct lchflags_args {
2637 	const char *path;
2638 	u_long flags;
2639 };
2640 #endif
2641 int
sys_lchflags(struct thread * td,struct lchflags_args * uap)2642 sys_lchflags(struct thread *td, struct lchflags_args *uap)
2643 {
2644 
2645 	return (kern_chflagsat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2646 	    uap->flags, AT_SYMLINK_NOFOLLOW));
2647 }
2648 
2649 static int
kern_chflagsat(struct thread * td,int fd,const char * path,enum uio_seg pathseg,u_long flags,int atflag)2650 kern_chflagsat(struct thread *td, int fd, const char *path,
2651     enum uio_seg pathseg, u_long flags, int atflag)
2652 {
2653 	struct nameidata nd;
2654 	int error, follow;
2655 
2656 	AUDIT_ARG_FFLAGS(flags);
2657 	follow = (atflag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
2658 	NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, pathseg, path, fd,
2659 	    &cap_fchflags_rights, td);
2660 	if ((error = namei(&nd)) != 0)
2661 		return (error);
2662 	NDFREE(&nd, NDF_ONLY_PNBUF);
2663 	error = setfflags(td, nd.ni_vp, flags);
2664 	vrele(nd.ni_vp);
2665 	return (error);
2666 }
2667 
2668 /*
2669  * Change flags of a file given a file descriptor.
2670  */
2671 #ifndef _SYS_SYSPROTO_H_
2672 struct fchflags_args {
2673 	int	fd;
2674 	u_long	flags;
2675 };
2676 #endif
2677 int
sys_fchflags(struct thread * td,struct fchflags_args * uap)2678 sys_fchflags(struct thread *td, struct fchflags_args *uap)
2679 {
2680 	struct file *fp;
2681 	int error;
2682 
2683 	AUDIT_ARG_FD(uap->fd);
2684 	AUDIT_ARG_FFLAGS(uap->flags);
2685 	error = getvnode(td, uap->fd, &cap_fchflags_rights,
2686 	    &fp);
2687 	if (error != 0)
2688 		return (error);
2689 #ifdef AUDIT
2690 	vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
2691 	AUDIT_ARG_VNODE1(fp->f_vnode);
2692 	VOP_UNLOCK(fp->f_vnode, 0);
2693 #endif
2694 	error = setfflags(td, fp->f_vnode, uap->flags);
2695 	fdrop(fp, td);
2696 	return (error);
2697 }
2698 
2699 /*
2700  * Common implementation code for chmod(), lchmod() and fchmod().
2701  */
2702 int
setfmode(struct thread * td,struct ucred * cred,struct vnode * vp,int mode)2703 setfmode(struct thread *td, struct ucred *cred, struct vnode *vp, int mode)
2704 {
2705 	struct mount *mp;
2706 	struct vattr vattr;
2707 	int error;
2708 
2709 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
2710 		return (error);
2711 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2712 	VATTR_NULL(&vattr);
2713 	vattr.va_mode = mode & ALLPERMS;
2714 #ifdef MAC
2715 	error = mac_vnode_check_setmode(cred, vp, vattr.va_mode);
2716 	if (error == 0)
2717 #endif
2718 		error = VOP_SETATTR(vp, &vattr, cred);
2719 	VOP_UNLOCK(vp, 0);
2720 	vn_finished_write(mp);
2721 	return (error);
2722 }
2723 
2724 /*
2725  * Change mode of a file given path name.
2726  */
2727 #ifndef _SYS_SYSPROTO_H_
2728 struct chmod_args {
2729 	char	*path;
2730 	int	mode;
2731 };
2732 #endif
2733 int
sys_chmod(struct thread * td,struct chmod_args * uap)2734 sys_chmod(struct thread *td, struct chmod_args *uap)
2735 {
2736 
2737 	return (kern_fchmodat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2738 	    uap->mode, 0));
2739 }
2740 
2741 #ifndef _SYS_SYSPROTO_H_
2742 struct fchmodat_args {
2743 	int	dirfd;
2744 	char	*path;
2745 	mode_t	mode;
2746 	int	flag;
2747 }
2748 #endif
2749 int
sys_fchmodat(struct thread * td,struct fchmodat_args * uap)2750 sys_fchmodat(struct thread *td, struct fchmodat_args *uap)
2751 {
2752 	int flag = uap->flag;
2753 	int fd = uap->fd;
2754 	char *path = uap->path;
2755 	mode_t mode = uap->mode;
2756 
2757 	if (flag & ~AT_SYMLINK_NOFOLLOW)
2758 		return (EINVAL);
2759 
2760 	return (kern_fchmodat(td, fd, path, UIO_USERSPACE, mode, flag));
2761 }
2762 
2763 /*
2764  * Change mode of a file given path name (don't follow links.)
2765  */
2766 #ifndef _SYS_SYSPROTO_H_
2767 struct lchmod_args {
2768 	char	*path;
2769 	int	mode;
2770 };
2771 #endif
2772 int
sys_lchmod(struct thread * td,struct lchmod_args * uap)2773 sys_lchmod(struct thread *td, struct lchmod_args *uap)
2774 {
2775 
2776 	return (kern_fchmodat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2777 	    uap->mode, AT_SYMLINK_NOFOLLOW));
2778 }
2779 
2780 int
kern_fchmodat(struct thread * td,int fd,char * path,enum uio_seg pathseg,mode_t mode,int flag)2781 kern_fchmodat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2782     mode_t mode, int flag)
2783 {
2784 	struct nameidata nd;
2785 	int error, follow;
2786 
2787 	AUDIT_ARG_MODE(mode);
2788 	follow = (flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
2789 	NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, pathseg, path, fd,
2790 	    &cap_fchmod_rights, td);
2791 	if ((error = namei(&nd)) != 0)
2792 		return (error);
2793 	NDFREE(&nd, NDF_ONLY_PNBUF);
2794 	error = setfmode(td, td->td_ucred, nd.ni_vp, mode);
2795 	vrele(nd.ni_vp);
2796 	return (error);
2797 }
2798 
2799 /*
2800  * Change mode of a file given a file descriptor.
2801  */
2802 #ifndef _SYS_SYSPROTO_H_
2803 struct fchmod_args {
2804 	int	fd;
2805 	int	mode;
2806 };
2807 #endif
2808 int
sys_fchmod(struct thread * td,struct fchmod_args * uap)2809 sys_fchmod(struct thread *td, struct fchmod_args *uap)
2810 {
2811 	struct file *fp;
2812 	int error;
2813 
2814 	AUDIT_ARG_FD(uap->fd);
2815 	AUDIT_ARG_MODE(uap->mode);
2816 
2817 	error = fget(td, uap->fd, &cap_fchmod_rights, &fp);
2818 	if (error != 0)
2819 		return (error);
2820 	error = fo_chmod(fp, uap->mode, td->td_ucred, td);
2821 	fdrop(fp, td);
2822 	return (error);
2823 }
2824 
2825 /*
2826  * Common implementation for chown(), lchown(), and fchown()
2827  */
2828 int
setfown(struct thread * td,struct ucred * cred,struct vnode * vp,uid_t uid,gid_t gid)2829 setfown(struct thread *td, struct ucred *cred, struct vnode *vp, uid_t uid,
2830     gid_t gid)
2831 {
2832 	struct mount *mp;
2833 	struct vattr vattr;
2834 	int error;
2835 
2836 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
2837 		return (error);
2838 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2839 	VATTR_NULL(&vattr);
2840 	vattr.va_uid = uid;
2841 	vattr.va_gid = gid;
2842 #ifdef MAC
2843 	error = mac_vnode_check_setowner(cred, vp, vattr.va_uid,
2844 	    vattr.va_gid);
2845 	if (error == 0)
2846 #endif
2847 		error = VOP_SETATTR(vp, &vattr, cred);
2848 	VOP_UNLOCK(vp, 0);
2849 	vn_finished_write(mp);
2850 	return (error);
2851 }
2852 
2853 /*
2854  * Set ownership given a path name.
2855  */
2856 #ifndef _SYS_SYSPROTO_H_
2857 struct chown_args {
2858 	char	*path;
2859 	int	uid;
2860 	int	gid;
2861 };
2862 #endif
2863 int
sys_chown(struct thread * td,struct chown_args * uap)2864 sys_chown(struct thread *td, struct chown_args *uap)
2865 {
2866 
2867 	return (kern_fchownat(td, AT_FDCWD, uap->path, UIO_USERSPACE, uap->uid,
2868 	    uap->gid, 0));
2869 }
2870 
2871 #ifndef _SYS_SYSPROTO_H_
2872 struct fchownat_args {
2873 	int fd;
2874 	const char * path;
2875 	uid_t uid;
2876 	gid_t gid;
2877 	int flag;
2878 };
2879 #endif
2880 int
sys_fchownat(struct thread * td,struct fchownat_args * uap)2881 sys_fchownat(struct thread *td, struct fchownat_args *uap)
2882 {
2883 	int flag;
2884 
2885 	flag = uap->flag;
2886 	if (flag & ~AT_SYMLINK_NOFOLLOW)
2887 		return (EINVAL);
2888 
2889 	return (kern_fchownat(td, uap->fd, uap->path, UIO_USERSPACE, uap->uid,
2890 	    uap->gid, uap->flag));
2891 }
2892 
2893 int
kern_fchownat(struct thread * td,int fd,char * path,enum uio_seg pathseg,int uid,int gid,int flag)2894 kern_fchownat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
2895     int uid, int gid, int flag)
2896 {
2897 	struct nameidata nd;
2898 	int error, follow;
2899 
2900 	AUDIT_ARG_OWNER(uid, gid);
2901 	follow = (flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW : FOLLOW;
2902 	NDINIT_ATRIGHTS(&nd, LOOKUP, follow | AUDITVNODE1, pathseg, path, fd,
2903 	    &cap_fchown_rights, td);
2904 
2905 	if ((error = namei(&nd)) != 0)
2906 		return (error);
2907 	NDFREE(&nd, NDF_ONLY_PNBUF);
2908 	error = setfown(td, td->td_ucred, nd.ni_vp, uid, gid);
2909 	vrele(nd.ni_vp);
2910 	return (error);
2911 }
2912 
2913 /*
2914  * Set ownership given a path name, do not cross symlinks.
2915  */
2916 #ifndef _SYS_SYSPROTO_H_
2917 struct lchown_args {
2918 	char	*path;
2919 	int	uid;
2920 	int	gid;
2921 };
2922 #endif
2923 int
sys_lchown(struct thread * td,struct lchown_args * uap)2924 sys_lchown(struct thread *td, struct lchown_args *uap)
2925 {
2926 
2927 	return (kern_fchownat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
2928 	    uap->uid, uap->gid, AT_SYMLINK_NOFOLLOW));
2929 }
2930 
2931 /*
2932  * Set ownership given a file descriptor.
2933  */
2934 #ifndef _SYS_SYSPROTO_H_
2935 struct fchown_args {
2936 	int	fd;
2937 	int	uid;
2938 	int	gid;
2939 };
2940 #endif
2941 int
sys_fchown(struct thread * td,struct fchown_args * uap)2942 sys_fchown(struct thread *td, struct fchown_args *uap)
2943 {
2944 	struct file *fp;
2945 	int error;
2946 
2947 	AUDIT_ARG_FD(uap->fd);
2948 	AUDIT_ARG_OWNER(uap->uid, uap->gid);
2949 	error = fget(td, uap->fd, &cap_fchown_rights, &fp);
2950 	if (error != 0)
2951 		return (error);
2952 	error = fo_chown(fp, uap->uid, uap->gid, td->td_ucred, td);
2953 	fdrop(fp, td);
2954 	return (error);
2955 }
2956 
2957 /*
2958  * Common implementation code for utimes(), lutimes(), and futimes().
2959  */
2960 static int
getutimes(const struct timeval * usrtvp,enum uio_seg tvpseg,struct timespec * tsp)2961 getutimes(const struct timeval *usrtvp, enum uio_seg tvpseg,
2962     struct timespec *tsp)
2963 {
2964 	struct timeval tv[2];
2965 	const struct timeval *tvp;
2966 	int error;
2967 
2968 	if (usrtvp == NULL) {
2969 		vfs_timestamp(&tsp[0]);
2970 		tsp[1] = tsp[0];
2971 	} else {
2972 		if (tvpseg == UIO_SYSSPACE) {
2973 			tvp = usrtvp;
2974 		} else {
2975 			if ((error = copyin(usrtvp, tv, sizeof(tv))) != 0)
2976 				return (error);
2977 			tvp = tv;
2978 		}
2979 
2980 		if (tvp[0].tv_usec < 0 || tvp[0].tv_usec >= 1000000 ||
2981 		    tvp[1].tv_usec < 0 || tvp[1].tv_usec >= 1000000)
2982 			return (EINVAL);
2983 		TIMEVAL_TO_TIMESPEC(&tvp[0], &tsp[0]);
2984 		TIMEVAL_TO_TIMESPEC(&tvp[1], &tsp[1]);
2985 	}
2986 	return (0);
2987 }
2988 
2989 /*
2990  * Common implementation code for futimens(), utimensat().
2991  */
2992 #define	UTIMENS_NULL	0x1
2993 #define	UTIMENS_EXIT	0x2
2994 static int
getutimens(const struct timespec * usrtsp,enum uio_seg tspseg,struct timespec * tsp,int * retflags)2995 getutimens(const struct timespec *usrtsp, enum uio_seg tspseg,
2996     struct timespec *tsp, int *retflags)
2997 {
2998 	struct timespec tsnow;
2999 	int error;
3000 
3001 	vfs_timestamp(&tsnow);
3002 	*retflags = 0;
3003 	if (usrtsp == NULL) {
3004 		tsp[0] = tsnow;
3005 		tsp[1] = tsnow;
3006 		*retflags |= UTIMENS_NULL;
3007 		return (0);
3008 	}
3009 	if (tspseg == UIO_SYSSPACE) {
3010 		tsp[0] = usrtsp[0];
3011 		tsp[1] = usrtsp[1];
3012 	} else if ((error = copyin(usrtsp, tsp, sizeof(*tsp) * 2)) != 0)
3013 		return (error);
3014 	if (tsp[0].tv_nsec == UTIME_OMIT && tsp[1].tv_nsec == UTIME_OMIT)
3015 		*retflags |= UTIMENS_EXIT;
3016 	if (tsp[0].tv_nsec == UTIME_NOW && tsp[1].tv_nsec == UTIME_NOW)
3017 		*retflags |= UTIMENS_NULL;
3018 	if (tsp[0].tv_nsec == UTIME_OMIT)
3019 		tsp[0].tv_sec = VNOVAL;
3020 	else if (tsp[0].tv_nsec == UTIME_NOW)
3021 		tsp[0] = tsnow;
3022 	else if (tsp[0].tv_nsec < 0 || tsp[0].tv_nsec >= 1000000000L)
3023 		return (EINVAL);
3024 	if (tsp[1].tv_nsec == UTIME_OMIT)
3025 		tsp[1].tv_sec = VNOVAL;
3026 	else if (tsp[1].tv_nsec == UTIME_NOW)
3027 		tsp[1] = tsnow;
3028 	else if (tsp[1].tv_nsec < 0 || tsp[1].tv_nsec >= 1000000000L)
3029 		return (EINVAL);
3030 
3031 	return (0);
3032 }
3033 
3034 /*
3035  * Common implementation code for utimes(), lutimes(), futimes(), futimens(),
3036  * and utimensat().
3037  */
3038 static int
setutimes(struct thread * td,struct vnode * vp,const struct timespec * ts,int numtimes,int nullflag)3039 setutimes(struct thread *td, struct vnode *vp, const struct timespec *ts,
3040     int numtimes, int nullflag)
3041 {
3042 	struct mount *mp;
3043 	struct vattr vattr;
3044 	int error, setbirthtime;
3045 
3046 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
3047 		return (error);
3048 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3049 	setbirthtime = 0;
3050 	if (numtimes < 3 && !VOP_GETATTR(vp, &vattr, td->td_ucred) &&
3051 	    timespeccmp(&ts[1], &vattr.va_birthtime, < ))
3052 		setbirthtime = 1;
3053 	VATTR_NULL(&vattr);
3054 	vattr.va_atime = ts[0];
3055 	vattr.va_mtime = ts[1];
3056 	if (setbirthtime)
3057 		vattr.va_birthtime = ts[1];
3058 	if (numtimes > 2)
3059 		vattr.va_birthtime = ts[2];
3060 	if (nullflag)
3061 		vattr.va_vaflags |= VA_UTIMES_NULL;
3062 #ifdef MAC
3063 	error = mac_vnode_check_setutimes(td->td_ucred, vp, vattr.va_atime,
3064 	    vattr.va_mtime);
3065 #endif
3066 	if (error == 0)
3067 		error = VOP_SETATTR(vp, &vattr, td->td_ucred);
3068 	VOP_UNLOCK(vp, 0);
3069 	vn_finished_write(mp);
3070 	return (error);
3071 }
3072 
3073 /*
3074  * Set the access and modification times of a file.
3075  */
3076 #ifndef _SYS_SYSPROTO_H_
3077 struct utimes_args {
3078 	char	*path;
3079 	struct	timeval *tptr;
3080 };
3081 #endif
3082 int
sys_utimes(struct thread * td,struct utimes_args * uap)3083 sys_utimes(struct thread *td, struct utimes_args *uap)
3084 {
3085 
3086 	return (kern_utimesat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
3087 	    uap->tptr, UIO_USERSPACE));
3088 }
3089 
3090 #ifndef _SYS_SYSPROTO_H_
3091 struct futimesat_args {
3092 	int fd;
3093 	const char * path;
3094 	const struct timeval * times;
3095 };
3096 #endif
3097 int
sys_futimesat(struct thread * td,struct futimesat_args * uap)3098 sys_futimesat(struct thread *td, struct futimesat_args *uap)
3099 {
3100 
3101 	return (kern_utimesat(td, uap->fd, uap->path, UIO_USERSPACE,
3102 	    uap->times, UIO_USERSPACE));
3103 }
3104 
3105 int
kern_utimesat(struct thread * td,int fd,char * path,enum uio_seg pathseg,struct timeval * tptr,enum uio_seg tptrseg)3106 kern_utimesat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
3107     struct timeval *tptr, enum uio_seg tptrseg)
3108 {
3109 	struct nameidata nd;
3110 	struct timespec ts[2];
3111 	int error;
3112 
3113 	if ((error = getutimes(tptr, tptrseg, ts)) != 0)
3114 		return (error);
3115 	NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, fd,
3116 	    &cap_futimes_rights, td);
3117 
3118 	if ((error = namei(&nd)) != 0)
3119 		return (error);
3120 	NDFREE(&nd, NDF_ONLY_PNBUF);
3121 	error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
3122 	vrele(nd.ni_vp);
3123 	return (error);
3124 }
3125 
3126 /*
3127  * Set the access and modification times of a file.
3128  */
3129 #ifndef _SYS_SYSPROTO_H_
3130 struct lutimes_args {
3131 	char	*path;
3132 	struct	timeval *tptr;
3133 };
3134 #endif
3135 int
sys_lutimes(struct thread * td,struct lutimes_args * uap)3136 sys_lutimes(struct thread *td, struct lutimes_args *uap)
3137 {
3138 
3139 	return (kern_lutimes(td, uap->path, UIO_USERSPACE, uap->tptr,
3140 	    UIO_USERSPACE));
3141 }
3142 
3143 int
kern_lutimes(struct thread * td,char * path,enum uio_seg pathseg,struct timeval * tptr,enum uio_seg tptrseg)3144 kern_lutimes(struct thread *td, char *path, enum uio_seg pathseg,
3145     struct timeval *tptr, enum uio_seg tptrseg)
3146 {
3147 	struct timespec ts[2];
3148 	struct nameidata nd;
3149 	int error;
3150 
3151 	if ((error = getutimes(tptr, tptrseg, ts)) != 0)
3152 		return (error);
3153 	NDINIT(&nd, LOOKUP, NOFOLLOW | AUDITVNODE1, pathseg, path, td);
3154 	if ((error = namei(&nd)) != 0)
3155 		return (error);
3156 	NDFREE(&nd, NDF_ONLY_PNBUF);
3157 	error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
3158 	vrele(nd.ni_vp);
3159 	return (error);
3160 }
3161 
3162 /*
3163  * Set the access and modification times of a file.
3164  */
3165 #ifndef _SYS_SYSPROTO_H_
3166 struct futimes_args {
3167 	int	fd;
3168 	struct	timeval *tptr;
3169 };
3170 #endif
3171 int
sys_futimes(struct thread * td,struct futimes_args * uap)3172 sys_futimes(struct thread *td, struct futimes_args *uap)
3173 {
3174 
3175 	return (kern_futimes(td, uap->fd, uap->tptr, UIO_USERSPACE));
3176 }
3177 
3178 int
kern_futimes(struct thread * td,int fd,struct timeval * tptr,enum uio_seg tptrseg)3179 kern_futimes(struct thread *td, int fd, struct timeval *tptr,
3180     enum uio_seg tptrseg)
3181 {
3182 	struct timespec ts[2];
3183 	struct file *fp;
3184 	int error;
3185 
3186 	AUDIT_ARG_FD(fd);
3187 	error = getutimes(tptr, tptrseg, ts);
3188 	if (error != 0)
3189 		return (error);
3190 	error = getvnode(td, fd, &cap_futimes_rights, &fp);
3191 	if (error != 0)
3192 		return (error);
3193 #ifdef AUDIT
3194 	vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
3195 	AUDIT_ARG_VNODE1(fp->f_vnode);
3196 	VOP_UNLOCK(fp->f_vnode, 0);
3197 #endif
3198 	error = setutimes(td, fp->f_vnode, ts, 2, tptr == NULL);
3199 	fdrop(fp, td);
3200 	return (error);
3201 }
3202 
3203 int
sys_futimens(struct thread * td,struct futimens_args * uap)3204 sys_futimens(struct thread *td, struct futimens_args *uap)
3205 {
3206 
3207 	return (kern_futimens(td, uap->fd, uap->times, UIO_USERSPACE));
3208 }
3209 
3210 int
kern_futimens(struct thread * td,int fd,struct timespec * tptr,enum uio_seg tptrseg)3211 kern_futimens(struct thread *td, int fd, struct timespec *tptr,
3212     enum uio_seg tptrseg)
3213 {
3214 	struct timespec ts[2];
3215 	struct file *fp;
3216 	int error, flags;
3217 
3218 	AUDIT_ARG_FD(fd);
3219 	error = getutimens(tptr, tptrseg, ts, &flags);
3220 	if (error != 0)
3221 		return (error);
3222 	if (flags & UTIMENS_EXIT)
3223 		return (0);
3224 	error = getvnode(td, fd, &cap_futimes_rights, &fp);
3225 	if (error != 0)
3226 		return (error);
3227 #ifdef AUDIT
3228 	vn_lock(fp->f_vnode, LK_SHARED | LK_RETRY);
3229 	AUDIT_ARG_VNODE1(fp->f_vnode);
3230 	VOP_UNLOCK(fp->f_vnode, 0);
3231 #endif
3232 	error = setutimes(td, fp->f_vnode, ts, 2, flags & UTIMENS_NULL);
3233 	fdrop(fp, td);
3234 	return (error);
3235 }
3236 
3237 int
sys_utimensat(struct thread * td,struct utimensat_args * uap)3238 sys_utimensat(struct thread *td, struct utimensat_args *uap)
3239 {
3240 
3241 	return (kern_utimensat(td, uap->fd, uap->path, UIO_USERSPACE,
3242 	    uap->times, UIO_USERSPACE, uap->flag));
3243 }
3244 
3245 int
kern_utimensat(struct thread * td,int fd,char * path,enum uio_seg pathseg,struct timespec * tptr,enum uio_seg tptrseg,int flag)3246 kern_utimensat(struct thread *td, int fd, char *path, enum uio_seg pathseg,
3247     struct timespec *tptr, enum uio_seg tptrseg, int flag)
3248 {
3249 	struct nameidata nd;
3250 	struct timespec ts[2];
3251 	int error, flags;
3252 
3253 	if (flag & ~AT_SYMLINK_NOFOLLOW)
3254 		return (EINVAL);
3255 
3256 	if ((error = getutimens(tptr, tptrseg, ts, &flags)) != 0)
3257 		return (error);
3258 	NDINIT_ATRIGHTS(&nd, LOOKUP, ((flag & AT_SYMLINK_NOFOLLOW) ? NOFOLLOW :
3259 	    FOLLOW) | AUDITVNODE1, pathseg, path, fd,
3260 	    &cap_futimes_rights, td);
3261 	if ((error = namei(&nd)) != 0)
3262 		return (error);
3263 	/*
3264 	 * We are allowed to call namei() regardless of 2xUTIME_OMIT.
3265 	 * POSIX states:
3266 	 * "If both tv_nsec fields are UTIME_OMIT... EACCESS may be detected."
3267 	 * "Search permission is denied by a component of the path prefix."
3268 	 */
3269 	NDFREE(&nd, NDF_ONLY_PNBUF);
3270 	if ((flags & UTIMENS_EXIT) == 0)
3271 		error = setutimes(td, nd.ni_vp, ts, 2, flags & UTIMENS_NULL);
3272 	vrele(nd.ni_vp);
3273 	return (error);
3274 }
3275 
3276 /*
3277  * Truncate a file given its path name.
3278  */
3279 #ifndef _SYS_SYSPROTO_H_
3280 struct truncate_args {
3281 	char	*path;
3282 	int	pad;
3283 	off_t	length;
3284 };
3285 #endif
3286 int
sys_truncate(struct thread * td,struct truncate_args * uap)3287 sys_truncate(struct thread *td, struct truncate_args *uap)
3288 {
3289 
3290 	return (kern_truncate(td, uap->path, UIO_USERSPACE, uap->length));
3291 }
3292 
3293 int
kern_truncate(struct thread * td,char * path,enum uio_seg pathseg,off_t length)3294 kern_truncate(struct thread *td, char *path, enum uio_seg pathseg, off_t length)
3295 {
3296 	struct mount *mp;
3297 	struct vnode *vp;
3298 	void *rl_cookie;
3299 	struct vattr vattr;
3300 	struct nameidata nd;
3301 	int error;
3302 
3303 	if (length < 0)
3304 		return(EINVAL);
3305 	NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, td);
3306 	if ((error = namei(&nd)) != 0)
3307 		return (error);
3308 	vp = nd.ni_vp;
3309 	rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3310 	if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
3311 		vn_rangelock_unlock(vp, rl_cookie);
3312 		vrele(vp);
3313 		return (error);
3314 	}
3315 	NDFREE(&nd, NDF_ONLY_PNBUF);
3316 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3317 	if (vp->v_type == VDIR)
3318 		error = EISDIR;
3319 #ifdef MAC
3320 	else if ((error = mac_vnode_check_write(td->td_ucred, NOCRED, vp))) {
3321 	}
3322 #endif
3323 	else if ((error = vn_writechk(vp)) == 0 &&
3324 	    (error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td)) == 0) {
3325 		VATTR_NULL(&vattr);
3326 		vattr.va_size = length;
3327 		error = VOP_SETATTR(vp, &vattr, td->td_ucred);
3328 	}
3329 	VOP_UNLOCK(vp, 0);
3330 	vn_finished_write(mp);
3331 	vn_rangelock_unlock(vp, rl_cookie);
3332 	vrele(vp);
3333 	return (error);
3334 }
3335 
3336 #if defined(COMPAT_43)
3337 /*
3338  * Truncate a file given its path name.
3339  */
3340 #ifndef _SYS_SYSPROTO_H_
3341 struct otruncate_args {
3342 	char	*path;
3343 	long	length;
3344 };
3345 #endif
3346 int
otruncate(struct thread * td,struct otruncate_args * uap)3347 otruncate(struct thread *td, struct otruncate_args *uap)
3348 {
3349 
3350 	return (kern_truncate(td, uap->path, UIO_USERSPACE, uap->length));
3351 }
3352 #endif /* COMPAT_43 */
3353 
3354 #if defined(COMPAT_FREEBSD6)
3355 /* Versions with the pad argument */
3356 int
freebsd6_truncate(struct thread * td,struct freebsd6_truncate_args * uap)3357 freebsd6_truncate(struct thread *td, struct freebsd6_truncate_args *uap)
3358 {
3359 
3360 	return (kern_truncate(td, uap->path, UIO_USERSPACE, uap->length));
3361 }
3362 
3363 int
freebsd6_ftruncate(struct thread * td,struct freebsd6_ftruncate_args * uap)3364 freebsd6_ftruncate(struct thread *td, struct freebsd6_ftruncate_args *uap)
3365 {
3366 
3367 	return (kern_ftruncate(td, uap->fd, uap->length));
3368 }
3369 #endif
3370 
3371 int
kern_fsync(struct thread * td,int fd,bool fullsync)3372 kern_fsync(struct thread *td, int fd, bool fullsync)
3373 {
3374 	struct vnode *vp;
3375 	struct mount *mp;
3376 	struct file *fp;
3377 	int error, lock_flags;
3378 
3379 	AUDIT_ARG_FD(fd);
3380 	error = getvnode(td, fd, &cap_fsync_rights, &fp);
3381 	if (error != 0)
3382 		return (error);
3383 	vp = fp->f_vnode;
3384 #if 0
3385 	if (!fullsync)
3386 		/* XXXKIB: compete outstanding aio writes */;
3387 #endif
3388 	error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
3389 	if (error != 0)
3390 		goto drop;
3391 	if (MNT_SHARED_WRITES(mp) ||
3392 	    ((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount))) {
3393 		lock_flags = LK_SHARED;
3394 	} else {
3395 		lock_flags = LK_EXCLUSIVE;
3396 	}
3397 	vn_lock(vp, lock_flags | LK_RETRY);
3398 	AUDIT_ARG_VNODE1(vp);
3399 	if (vp->v_object != NULL) {
3400 		VM_OBJECT_WLOCK(vp->v_object);
3401 		vm_object_page_clean(vp->v_object, 0, 0, 0);
3402 		VM_OBJECT_WUNLOCK(vp->v_object);
3403 	}
3404 	error = fullsync ? VOP_FSYNC(vp, MNT_WAIT, td) : VOP_FDATASYNC(vp, td);
3405 	VOP_UNLOCK(vp, 0);
3406 	vn_finished_write(mp);
3407 drop:
3408 	fdrop(fp, td);
3409 	return (error);
3410 }
3411 
3412 /*
3413  * Sync an open file.
3414  */
3415 #ifndef _SYS_SYSPROTO_H_
3416 struct fsync_args {
3417 	int	fd;
3418 };
3419 #endif
3420 int
sys_fsync(struct thread * td,struct fsync_args * uap)3421 sys_fsync(struct thread *td, struct fsync_args *uap)
3422 {
3423 
3424 	return (kern_fsync(td, uap->fd, true));
3425 }
3426 
3427 int
sys_fdatasync(struct thread * td,struct fdatasync_args * uap)3428 sys_fdatasync(struct thread *td, struct fdatasync_args *uap)
3429 {
3430 
3431 	return (kern_fsync(td, uap->fd, false));
3432 }
3433 
3434 /*
3435  * Rename files.  Source and destination must either both be directories, or
3436  * both not be directories.  If target is a directory, it must be empty.
3437  */
3438 #ifndef _SYS_SYSPROTO_H_
3439 struct rename_args {
3440 	char	*from;
3441 	char	*to;
3442 };
3443 #endif
3444 int
sys_rename(struct thread * td,struct rename_args * uap)3445 sys_rename(struct thread *td, struct rename_args *uap)
3446 {
3447 
3448 	return (kern_renameat(td, AT_FDCWD, uap->from, AT_FDCWD,
3449 	    uap->to, UIO_USERSPACE));
3450 }
3451 
3452 #ifndef _SYS_SYSPROTO_H_
3453 struct renameat_args {
3454 	int	oldfd;
3455 	char	*old;
3456 	int	newfd;
3457 	char	*new;
3458 };
3459 #endif
3460 int
sys_renameat(struct thread * td,struct renameat_args * uap)3461 sys_renameat(struct thread *td, struct renameat_args *uap)
3462 {
3463 
3464 	return (kern_renameat(td, uap->oldfd, uap->old, uap->newfd, uap->new,
3465 	    UIO_USERSPACE));
3466 }
3467 
3468 int
kern_renameat(struct thread * td,int oldfd,char * old,int newfd,char * new,enum uio_seg pathseg)3469 kern_renameat(struct thread *td, int oldfd, char *old, int newfd, char *new,
3470     enum uio_seg pathseg)
3471 {
3472 	struct mount *mp = NULL;
3473 	struct vnode *tvp, *fvp, *tdvp;
3474 	struct nameidata fromnd, tond;
3475 	int error;
3476 
3477 again:
3478 	bwillwrite();
3479 #ifdef MAC
3480 	NDINIT_ATRIGHTS(&fromnd, DELETE, LOCKPARENT | LOCKLEAF | SAVESTART |
3481 	    AUDITVNODE1, pathseg, old, oldfd,
3482 	    &cap_renameat_source_rights, td);
3483 #else
3484 	NDINIT_ATRIGHTS(&fromnd, DELETE, WANTPARENT | SAVESTART | AUDITVNODE1,
3485 	    pathseg, old, oldfd,
3486 	    &cap_renameat_source_rights, td);
3487 #endif
3488 
3489 	if ((error = namei(&fromnd)) != 0)
3490 		return (error);
3491 #ifdef MAC
3492 	error = mac_vnode_check_rename_from(td->td_ucred, fromnd.ni_dvp,
3493 	    fromnd.ni_vp, &fromnd.ni_cnd);
3494 	VOP_UNLOCK(fromnd.ni_dvp, 0);
3495 	if (fromnd.ni_dvp != fromnd.ni_vp)
3496 		VOP_UNLOCK(fromnd.ni_vp, 0);
3497 #endif
3498 	fvp = fromnd.ni_vp;
3499 	NDINIT_ATRIGHTS(&tond, RENAME, LOCKPARENT | LOCKLEAF | NOCACHE |
3500 	    SAVESTART | AUDITVNODE2, pathseg, new, newfd,
3501 	    &cap_renameat_target_rights, td);
3502 	if (fromnd.ni_vp->v_type == VDIR)
3503 		tond.ni_cnd.cn_flags |= WILLBEDIR;
3504 	if ((error = namei(&tond)) != 0) {
3505 		/* Translate error code for rename("dir1", "dir2/."). */
3506 		if (error == EISDIR && fvp->v_type == VDIR)
3507 			error = EINVAL;
3508 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3509 		vrele(fromnd.ni_dvp);
3510 		vrele(fvp);
3511 		goto out1;
3512 	}
3513 	tdvp = tond.ni_dvp;
3514 	tvp = tond.ni_vp;
3515 	error = vn_start_write(fvp, &mp, V_NOWAIT);
3516 	if (error != 0) {
3517 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3518 		NDFREE(&tond, NDF_ONLY_PNBUF);
3519 		if (tvp != NULL)
3520 			vput(tvp);
3521 		if (tdvp == tvp)
3522 			vrele(tdvp);
3523 		else
3524 			vput(tdvp);
3525 		vrele(fromnd.ni_dvp);
3526 		vrele(fvp);
3527 		vrele(tond.ni_startdir);
3528 		if (fromnd.ni_startdir != NULL)
3529 			vrele(fromnd.ni_startdir);
3530 		error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH);
3531 		if (error != 0)
3532 			return (error);
3533 		goto again;
3534 	}
3535 	if (tvp != NULL) {
3536 		if (fvp->v_type == VDIR && tvp->v_type != VDIR) {
3537 			error = ENOTDIR;
3538 			goto out;
3539 		} else if (fvp->v_type != VDIR && tvp->v_type == VDIR) {
3540 			error = EISDIR;
3541 			goto out;
3542 		}
3543 #ifdef CAPABILITIES
3544 		if (newfd != AT_FDCWD && (tond.ni_resflags & NIRES_ABS) == 0) {
3545 			/*
3546 			 * If the target already exists we require CAP_UNLINKAT
3547 			 * from 'newfd', when newfd was used for the lookup.
3548 			 */
3549 			error = cap_check(&tond.ni_filecaps.fc_rights,
3550 			    &cap_unlinkat_rights);
3551 			if (error != 0)
3552 				goto out;
3553 		}
3554 #endif
3555 	}
3556 	if (fvp == tdvp) {
3557 		error = EINVAL;
3558 		goto out;
3559 	}
3560 	/*
3561 	 * If the source is the same as the destination (that is, if they
3562 	 * are links to the same vnode), then there is nothing to do.
3563 	 */
3564 	if (fvp == tvp)
3565 		error = -1;
3566 #ifdef MAC
3567 	else
3568 		error = mac_vnode_check_rename_to(td->td_ucred, tdvp,
3569 		    tond.ni_vp, fromnd.ni_dvp == tdvp, &tond.ni_cnd);
3570 #endif
3571 out:
3572 	if (error == 0) {
3573 		error = VOP_RENAME(fromnd.ni_dvp, fromnd.ni_vp, &fromnd.ni_cnd,
3574 		    tond.ni_dvp, tond.ni_vp, &tond.ni_cnd);
3575 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3576 		NDFREE(&tond, NDF_ONLY_PNBUF);
3577 	} else {
3578 		NDFREE(&fromnd, NDF_ONLY_PNBUF);
3579 		NDFREE(&tond, NDF_ONLY_PNBUF);
3580 		if (tvp != NULL)
3581 			vput(tvp);
3582 		if (tdvp == tvp)
3583 			vrele(tdvp);
3584 		else
3585 			vput(tdvp);
3586 		vrele(fromnd.ni_dvp);
3587 		vrele(fvp);
3588 	}
3589 	vrele(tond.ni_startdir);
3590 	vn_finished_write(mp);
3591 out1:
3592 	if (fromnd.ni_startdir)
3593 		vrele(fromnd.ni_startdir);
3594 	if (error == -1)
3595 		return (0);
3596 	return (error);
3597 }
3598 
3599 /*
3600  * Make a directory file.
3601  */
3602 #ifndef _SYS_SYSPROTO_H_
3603 struct mkdir_args {
3604 	char	*path;
3605 	int	mode;
3606 };
3607 #endif
3608 int
sys_mkdir(struct thread * td,struct mkdir_args * uap)3609 sys_mkdir(struct thread *td, struct mkdir_args *uap)
3610 {
3611 
3612 	return (kern_mkdirat(td, AT_FDCWD, uap->path, UIO_USERSPACE,
3613 	    uap->mode));
3614 }
3615 
3616 #ifndef _SYS_SYSPROTO_H_
3617 struct mkdirat_args {
3618 	int	fd;
3619 	char	*path;
3620 	mode_t	mode;
3621 };
3622 #endif
3623 int
sys_mkdirat(struct thread * td,struct mkdirat_args * uap)3624 sys_mkdirat(struct thread *td, struct mkdirat_args *uap)
3625 {
3626 
3627 	return (kern_mkdirat(td, uap->fd, uap->path, UIO_USERSPACE, uap->mode));
3628 }
3629 
3630 int
kern_mkdirat(struct thread * td,int fd,char * path,enum uio_seg segflg,int mode)3631 kern_mkdirat(struct thread *td, int fd, char *path, enum uio_seg segflg,
3632     int mode)
3633 {
3634 	struct mount *mp;
3635 	struct vnode *vp;
3636 	struct vattr vattr;
3637 	struct nameidata nd;
3638 	int error;
3639 
3640 	AUDIT_ARG_MODE(mode);
3641 restart:
3642 	bwillwrite();
3643 	NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE1 |
3644 	    NOCACHE, segflg, path, fd, &cap_mkdirat_rights,
3645 	    td);
3646 	nd.ni_cnd.cn_flags |= WILLBEDIR;
3647 	if ((error = namei(&nd)) != 0)
3648 		return (error);
3649 	vp = nd.ni_vp;
3650 	if (vp != NULL) {
3651 		NDFREE(&nd, NDF_ONLY_PNBUF);
3652 		/*
3653 		 * XXX namei called with LOCKPARENT but not LOCKLEAF has
3654 		 * the strange behaviour of leaving the vnode unlocked
3655 		 * if the target is the same vnode as the parent.
3656 		 */
3657 		if (vp == nd.ni_dvp)
3658 			vrele(nd.ni_dvp);
3659 		else
3660 			vput(nd.ni_dvp);
3661 		vrele(vp);
3662 		return (EEXIST);
3663 	}
3664 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
3665 		NDFREE(&nd, NDF_ONLY_PNBUF);
3666 		vput(nd.ni_dvp);
3667 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3668 			return (error);
3669 		goto restart;
3670 	}
3671 	VATTR_NULL(&vattr);
3672 	vattr.va_type = VDIR;
3673 	vattr.va_mode = (mode & ACCESSPERMS) &~ td->td_proc->p_fd->fd_cmask;
3674 #ifdef MAC
3675 	error = mac_vnode_check_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
3676 	    &vattr);
3677 	if (error != 0)
3678 		goto out;
3679 #endif
3680 	error = VOP_MKDIR(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
3681 #ifdef MAC
3682 out:
3683 #endif
3684 	NDFREE(&nd, NDF_ONLY_PNBUF);
3685 	vput(nd.ni_dvp);
3686 	if (error == 0)
3687 		vput(nd.ni_vp);
3688 	vn_finished_write(mp);
3689 	return (error);
3690 }
3691 
3692 /*
3693  * Remove a directory file.
3694  */
3695 #ifndef _SYS_SYSPROTO_H_
3696 struct rmdir_args {
3697 	char	*path;
3698 };
3699 #endif
3700 int
sys_rmdir(struct thread * td,struct rmdir_args * uap)3701 sys_rmdir(struct thread *td, struct rmdir_args *uap)
3702 {
3703 
3704 	return (kern_rmdirat(td, AT_FDCWD, uap->path, UIO_USERSPACE));
3705 }
3706 
3707 int
kern_rmdirat(struct thread * td,int fd,char * path,enum uio_seg pathseg)3708 kern_rmdirat(struct thread *td, int fd, char *path, enum uio_seg pathseg)
3709 {
3710 	struct mount *mp;
3711 	struct vnode *vp;
3712 	struct nameidata nd;
3713 	int error;
3714 
3715 restart:
3716 	bwillwrite();
3717 	NDINIT_ATRIGHTS(&nd, DELETE, LOCKPARENT | LOCKLEAF | AUDITVNODE1,
3718 	    pathseg, path, fd, &cap_unlinkat_rights, td);
3719 	if ((error = namei(&nd)) != 0)
3720 		return (error);
3721 	vp = nd.ni_vp;
3722 	if (vp->v_type != VDIR) {
3723 		error = ENOTDIR;
3724 		goto out;
3725 	}
3726 	/*
3727 	 * No rmdir "." please.
3728 	 */
3729 	if (nd.ni_dvp == vp) {
3730 		error = EINVAL;
3731 		goto out;
3732 	}
3733 	/*
3734 	 * The root of a mounted filesystem cannot be deleted.
3735 	 */
3736 	if (vp->v_vflag & VV_ROOT) {
3737 		error = EBUSY;
3738 		goto out;
3739 	}
3740 #ifdef MAC
3741 	error = mac_vnode_check_unlink(td->td_ucred, nd.ni_dvp, vp,
3742 	    &nd.ni_cnd);
3743 	if (error != 0)
3744 		goto out;
3745 #endif
3746 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
3747 		NDFREE(&nd, NDF_ONLY_PNBUF);
3748 		vput(vp);
3749 		if (nd.ni_dvp == vp)
3750 			vrele(nd.ni_dvp);
3751 		else
3752 			vput(nd.ni_dvp);
3753 		if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3754 			return (error);
3755 		goto restart;
3756 	}
3757 	vfs_notify_upper(vp, VFS_NOTIFY_UPPER_UNLINK);
3758 	error = VOP_RMDIR(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
3759 	vn_finished_write(mp);
3760 out:
3761 	NDFREE(&nd, NDF_ONLY_PNBUF);
3762 	vput(vp);
3763 	if (nd.ni_dvp == vp)
3764 		vrele(nd.ni_dvp);
3765 	else
3766 		vput(nd.ni_dvp);
3767 	return (error);
3768 }
3769 
3770 #if defined(COMPAT_43) || defined(COMPAT_FREEBSD11)
3771 int
freebsd11_kern_getdirentries(struct thread * td,int fd,char * ubuf,u_int count,long * basep,void (* func)(struct freebsd11_dirent *))3772 freebsd11_kern_getdirentries(struct thread *td, int fd, char *ubuf, u_int count,
3773     long *basep, void (*func)(struct freebsd11_dirent *))
3774 {
3775 	struct freebsd11_dirent dstdp;
3776 	struct dirent *dp, *edp;
3777 	char *dirbuf;
3778 	off_t base;
3779 	ssize_t resid, ucount;
3780 	int error;
3781 
3782 	/* XXX arbitrary sanity limit on `count'. */
3783 	count = min(count, 64 * 1024);
3784 
3785 	dirbuf = malloc(count, M_TEMP, M_WAITOK);
3786 
3787 	error = kern_getdirentries(td, fd, dirbuf, count, &base, &resid,
3788 	    UIO_SYSSPACE);
3789 	if (error != 0)
3790 		goto done;
3791 	if (basep != NULL)
3792 		*basep = base;
3793 
3794 	ucount = 0;
3795 	for (dp = (struct dirent *)dirbuf,
3796 	    edp = (struct dirent *)&dirbuf[count - resid];
3797 	    ucount < count && dp < edp; ) {
3798 		if (dp->d_reclen == 0)
3799 			break;
3800 		MPASS(dp->d_reclen >= _GENERIC_DIRLEN(0));
3801 		if (dp->d_namlen >= sizeof(dstdp.d_name))
3802 			continue;
3803 		dstdp.d_type = dp->d_type;
3804 		dstdp.d_namlen = dp->d_namlen;
3805 		dstdp.d_fileno = dp->d_fileno;		/* truncate */
3806 		if (dstdp.d_fileno != dp->d_fileno) {
3807 			switch (ino64_trunc_error) {
3808 			default:
3809 			case 0:
3810 				break;
3811 			case 1:
3812 				error = EOVERFLOW;
3813 				goto done;
3814 			case 2:
3815 				dstdp.d_fileno = UINT32_MAX;
3816 				break;
3817 			}
3818 		}
3819 		dstdp.d_reclen = sizeof(dstdp) - sizeof(dstdp.d_name) +
3820 		    ((dp->d_namlen + 1 + 3) &~ 3);
3821 		bcopy(dp->d_name, dstdp.d_name, dstdp.d_namlen);
3822 		bzero(dstdp.d_name + dstdp.d_namlen,
3823 		    dstdp.d_reclen - offsetof(struct freebsd11_dirent, d_name) -
3824 		    dstdp.d_namlen);
3825 		MPASS(dstdp.d_reclen <= dp->d_reclen);
3826 		MPASS(ucount + dstdp.d_reclen <= count);
3827 		if (func != NULL)
3828 			func(&dstdp);
3829 		error = copyout(&dstdp, ubuf + ucount, dstdp.d_reclen);
3830 		if (error != 0)
3831 			break;
3832 		dp = (struct dirent *)((char *)dp + dp->d_reclen);
3833 		ucount += dstdp.d_reclen;
3834 	}
3835 
3836 done:
3837 	free(dirbuf, M_TEMP);
3838 	if (error == 0)
3839 		td->td_retval[0] = ucount;
3840 	return (error);
3841 }
3842 #endif /* COMPAT */
3843 
3844 #ifdef COMPAT_43
3845 static void
ogetdirentries_cvt(struct freebsd11_dirent * dp)3846 ogetdirentries_cvt(struct freebsd11_dirent *dp)
3847 {
3848 #if (BYTE_ORDER == LITTLE_ENDIAN)
3849 	/*
3850 	 * The expected low byte of dp->d_namlen is our dp->d_type.
3851 	 * The high MBZ byte of dp->d_namlen is our dp->d_namlen.
3852 	 */
3853 	dp->d_type = dp->d_namlen;
3854 	dp->d_namlen = 0;
3855 #else
3856 	/*
3857 	 * The dp->d_type is the high byte of the expected dp->d_namlen,
3858 	 * so must be zero'ed.
3859 	 */
3860 	dp->d_type = 0;
3861 #endif
3862 }
3863 
3864 /*
3865  * Read a block of directory entries in a filesystem independent format.
3866  */
3867 #ifndef _SYS_SYSPROTO_H_
3868 struct ogetdirentries_args {
3869 	int	fd;
3870 	char	*buf;
3871 	u_int	count;
3872 	long	*basep;
3873 };
3874 #endif
3875 int
ogetdirentries(struct thread * td,struct ogetdirentries_args * uap)3876 ogetdirentries(struct thread *td, struct ogetdirentries_args *uap)
3877 {
3878 	long loff;
3879 	int error;
3880 
3881 	error = kern_ogetdirentries(td, uap, &loff);
3882 	if (error == 0)
3883 		error = copyout(&loff, uap->basep, sizeof(long));
3884 	return (error);
3885 }
3886 
3887 int
kern_ogetdirentries(struct thread * td,struct ogetdirentries_args * uap,long * ploff)3888 kern_ogetdirentries(struct thread *td, struct ogetdirentries_args *uap,
3889     long *ploff)
3890 {
3891 	long base;
3892 	int error;
3893 
3894 	/* XXX arbitrary sanity limit on `count'. */
3895 	if (uap->count > 64 * 1024)
3896 		return (EINVAL);
3897 
3898 	error = freebsd11_kern_getdirentries(td, uap->fd, uap->buf, uap->count,
3899 	    &base, ogetdirentries_cvt);
3900 
3901 	if (error == 0 && uap->basep != NULL)
3902 		error = copyout(&base, uap->basep, sizeof(long));
3903 
3904 	return (error);
3905 }
3906 #endif /* COMPAT_43 */
3907 
3908 #if defined(COMPAT_FREEBSD11)
3909 #ifndef _SYS_SYSPROTO_H_
3910 struct freebsd11_getdirentries_args {
3911 	int	fd;
3912 	char	*buf;
3913 	u_int	count;
3914 	long	*basep;
3915 };
3916 #endif
3917 int
freebsd11_getdirentries(struct thread * td,struct freebsd11_getdirentries_args * uap)3918 freebsd11_getdirentries(struct thread *td,
3919     struct freebsd11_getdirentries_args *uap)
3920 {
3921 	long base;
3922 	int error;
3923 
3924 	error = freebsd11_kern_getdirentries(td, uap->fd, uap->buf, uap->count,
3925 	    &base, NULL);
3926 
3927 	if (error == 0 && uap->basep != NULL)
3928 		error = copyout(&base, uap->basep, sizeof(long));
3929 	return (error);
3930 }
3931 
3932 int
freebsd11_getdents(struct thread * td,struct freebsd11_getdents_args * uap)3933 freebsd11_getdents(struct thread *td, struct freebsd11_getdents_args *uap)
3934 {
3935 	struct freebsd11_getdirentries_args ap;
3936 
3937 	ap.fd = uap->fd;
3938 	ap.buf = uap->buf;
3939 	ap.count = uap->count;
3940 	ap.basep = NULL;
3941 	return (freebsd11_getdirentries(td, &ap));
3942 }
3943 #endif /* COMPAT_FREEBSD11 */
3944 
3945 /*
3946  * Read a block of directory entries in a filesystem independent format.
3947  */
3948 int
sys_getdirentries(struct thread * td,struct getdirentries_args * uap)3949 sys_getdirentries(struct thread *td, struct getdirentries_args *uap)
3950 {
3951 	off_t base;
3952 	int error;
3953 
3954 	error = kern_getdirentries(td, uap->fd, uap->buf, uap->count, &base,
3955 	    NULL, UIO_USERSPACE);
3956 	if (error != 0)
3957 		return (error);
3958 	if (uap->basep != NULL)
3959 		error = copyout(&base, uap->basep, sizeof(off_t));
3960 	return (error);
3961 }
3962 
3963 int
kern_getdirentries(struct thread * td,int fd,char * buf,size_t count,off_t * basep,ssize_t * residp,enum uio_seg bufseg)3964 kern_getdirentries(struct thread *td, int fd, char *buf, size_t count,
3965     off_t *basep, ssize_t *residp, enum uio_seg bufseg)
3966 {
3967 	struct vnode *vp;
3968 	struct file *fp;
3969 	struct uio auio;
3970 	struct iovec aiov;
3971 	off_t loff;
3972 	int error, eofflag;
3973 	off_t foffset;
3974 
3975 	AUDIT_ARG_FD(fd);
3976 	if (count > IOSIZE_MAX)
3977 		return (EINVAL);
3978 	auio.uio_resid = count;
3979 	error = getvnode(td, fd, &cap_read_rights, &fp);
3980 	if (error != 0)
3981 		return (error);
3982 	if ((fp->f_flag & FREAD) == 0) {
3983 		fdrop(fp, td);
3984 		return (EBADF);
3985 	}
3986 	vp = fp->f_vnode;
3987 	foffset = foffset_lock(fp, 0);
3988 unionread:
3989 	if (vp->v_type != VDIR) {
3990 		error = EINVAL;
3991 		goto fail;
3992 	}
3993 	aiov.iov_base = buf;
3994 	aiov.iov_len = count;
3995 	auio.uio_iov = &aiov;
3996 	auio.uio_iovcnt = 1;
3997 	auio.uio_rw = UIO_READ;
3998 	auio.uio_segflg = bufseg;
3999 	auio.uio_td = td;
4000 	vn_lock(vp, LK_SHARED | LK_RETRY);
4001 	AUDIT_ARG_VNODE1(vp);
4002 	loff = auio.uio_offset = foffset;
4003 #ifdef MAC
4004 	error = mac_vnode_check_readdir(td->td_ucred, vp);
4005 	if (error == 0)
4006 #endif
4007 		error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, NULL,
4008 		    NULL);
4009 	foffset = auio.uio_offset;
4010 	if (error != 0) {
4011 		VOP_UNLOCK(vp, 0);
4012 		goto fail;
4013 	}
4014 	if (count == auio.uio_resid &&
4015 	    (vp->v_vflag & VV_ROOT) &&
4016 	    (vp->v_mount->mnt_flag & MNT_UNION)) {
4017 		struct vnode *tvp = vp;
4018 
4019 		vp = vp->v_mount->mnt_vnodecovered;
4020 		VREF(vp);
4021 		fp->f_vnode = vp;
4022 		fp->f_data = vp;
4023 		foffset = 0;
4024 		vput(tvp);
4025 		goto unionread;
4026 	}
4027 	VOP_UNLOCK(vp, 0);
4028 	*basep = loff;
4029 	if (residp != NULL)
4030 		*residp = auio.uio_resid;
4031 	td->td_retval[0] = count - auio.uio_resid;
4032 fail:
4033 	foffset_unlock(fp, foffset, 0);
4034 	fdrop(fp, td);
4035 	return (error);
4036 }
4037 
4038 /*
4039  * Set the mode mask for creation of filesystem nodes.
4040  */
4041 #ifndef _SYS_SYSPROTO_H_
4042 struct umask_args {
4043 	int	newmask;
4044 };
4045 #endif
4046 int
sys_umask(struct thread * td,struct umask_args * uap)4047 sys_umask(struct thread *td, struct umask_args *uap)
4048 {
4049 	struct filedesc *fdp;
4050 
4051 	fdp = td->td_proc->p_fd;
4052 	FILEDESC_XLOCK(fdp);
4053 	td->td_retval[0] = fdp->fd_cmask;
4054 	fdp->fd_cmask = uap->newmask & ALLPERMS;
4055 	FILEDESC_XUNLOCK(fdp);
4056 	return (0);
4057 }
4058 
4059 /*
4060  * Void all references to file by ripping underlying filesystem away from
4061  * vnode.
4062  */
4063 #ifndef _SYS_SYSPROTO_H_
4064 struct revoke_args {
4065 	char	*path;
4066 };
4067 #endif
4068 int
sys_revoke(struct thread * td,struct revoke_args * uap)4069 sys_revoke(struct thread *td, struct revoke_args *uap)
4070 {
4071 	struct vnode *vp;
4072 	struct vattr vattr;
4073 	struct nameidata nd;
4074 	int error;
4075 
4076 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
4077 	    uap->path, td);
4078 	if ((error = namei(&nd)) != 0)
4079 		return (error);
4080 	vp = nd.ni_vp;
4081 	NDFREE(&nd, NDF_ONLY_PNBUF);
4082 	if (vp->v_type != VCHR || vp->v_rdev == NULL) {
4083 		error = EINVAL;
4084 		goto out;
4085 	}
4086 #ifdef MAC
4087 	error = mac_vnode_check_revoke(td->td_ucred, vp);
4088 	if (error != 0)
4089 		goto out;
4090 #endif
4091 	error = VOP_GETATTR(vp, &vattr, td->td_ucred);
4092 	if (error != 0)
4093 		goto out;
4094 	if (td->td_ucred->cr_uid != vattr.va_uid) {
4095 		error = priv_check(td, PRIV_VFS_ADMIN);
4096 		if (error != 0)
4097 			goto out;
4098 	}
4099 	if (vcount(vp) > 1)
4100 		VOP_REVOKE(vp, REVOKEALL);
4101 out:
4102 	vput(vp);
4103 	return (error);
4104 }
4105 
4106 /*
4107  * Convert a user file descriptor to a kernel file entry and check that, if it
4108  * is a capability, the correct rights are present. A reference on the file
4109  * entry is held upon returning.
4110  */
4111 int
getvnode(struct thread * td,int fd,cap_rights_t * rightsp,struct file ** fpp)4112 getvnode(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp)
4113 {
4114 	struct file *fp;
4115 	int error;
4116 
4117 	error = fget_unlocked(td->td_proc->p_fd, fd, rightsp, &fp, NULL);
4118 	if (error != 0)
4119 		return (error);
4120 
4121 	/*
4122 	 * The file could be not of the vnode type, or it may be not
4123 	 * yet fully initialized, in which case the f_vnode pointer
4124 	 * may be set, but f_ops is still badfileops.  E.g.,
4125 	 * devfs_open() transiently create such situation to
4126 	 * facilitate csw d_fdopen().
4127 	 *
4128 	 * Dupfdopen() handling in kern_openat() installs the
4129 	 * half-baked file into the process descriptor table, allowing
4130 	 * other thread to dereference it. Guard against the race by
4131 	 * checking f_ops.
4132 	 */
4133 	if (fp->f_vnode == NULL || fp->f_ops == &badfileops) {
4134 		fdrop(fp, td);
4135 		return (EINVAL);
4136 	}
4137 	*fpp = fp;
4138 	return (0);
4139 }
4140 
4141 
4142 /*
4143  * Get an (NFS) file handle.
4144  */
4145 #ifndef _SYS_SYSPROTO_H_
4146 struct lgetfh_args {
4147 	char *fname;
4148 	fhandle_t *fhp;
4149 };
4150 #endif
4151 int
sys_lgetfh(struct thread * td,struct lgetfh_args * uap)4152 sys_lgetfh(struct thread *td, struct lgetfh_args *uap)
4153 {
4154 
4155 	return (kern_getfhat(td, AT_SYMLINK_NOFOLLOW, AT_FDCWD, uap->fname,
4156 	    UIO_USERSPACE, uap->fhp));
4157 }
4158 
4159 #ifndef _SYS_SYSPROTO_H_
4160 struct getfh_args {
4161 	char *fname;
4162 	fhandle_t *fhp;
4163 };
4164 #endif
4165 int
sys_getfh(struct thread * td,struct getfh_args * uap)4166 sys_getfh(struct thread *td, struct getfh_args *uap)
4167 {
4168 
4169 	return (kern_getfhat(td, 0, AT_FDCWD, uap->fname, UIO_USERSPACE,
4170 	    uap->fhp));
4171 }
4172 
4173 /*
4174  * syscall for the rpc.lockd to use to translate an open descriptor into
4175  * a NFS file handle.
4176  *
4177  * warning: do not remove the priv_check() call or this becomes one giant
4178  * security hole.
4179  */
4180 #ifndef _SYS_SYSPROTO_H_
4181 struct getfhat_args {
4182 	int fd;
4183 	char *path;
4184 	fhandle_t *fhp;
4185 	int flags;
4186 };
4187 #endif
4188 int
sys_getfhat(struct thread * td,struct getfhat_args * uap)4189 sys_getfhat(struct thread *td, struct getfhat_args *uap)
4190 {
4191 
4192 	if ((uap->flags & ~(AT_SYMLINK_NOFOLLOW)) != 0)
4193 	    return (EINVAL);
4194 	return (kern_getfhat(td, uap->flags, uap->fd, uap->path, UIO_USERSPACE,
4195 	    uap->fhp));
4196 }
4197 
4198 static int
kern_getfhat(struct thread * td,int flags,int fd,const char * path,enum uio_seg pathseg,fhandle_t * fhp)4199 kern_getfhat(struct thread *td, int flags, int fd, const char *path,
4200     enum uio_seg pathseg, fhandle_t *fhp)
4201 {
4202 	struct nameidata nd;
4203 	fhandle_t fh;
4204 	struct vnode *vp;
4205 	int error;
4206 
4207 	error = priv_check(td, PRIV_VFS_GETFH);
4208 	if (error != 0)
4209 		return (error);
4210 	NDINIT_AT(&nd, LOOKUP, ((flags & AT_SYMLINK_NOFOLLOW) != 0 ? NOFOLLOW :
4211 	    FOLLOW) | /*((flags & AT_BENEATH) != 0 ? BENEATH : 0) |*/ LOCKLEAF |
4212 	    AUDITVNODE1, pathseg, path, fd, td);
4213 	error = namei(&nd);
4214 	if (error != 0)
4215 		return (error);
4216 	NDFREE(&nd, NDF_ONLY_PNBUF);
4217 	vp = nd.ni_vp;
4218 	bzero(&fh, sizeof(fh));
4219 	fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
4220 	error = VOP_VPTOFH(vp, &fh.fh_fid);
4221 	vput(vp);
4222 	if (error == 0)
4223 		error = copyout(&fh, fhp, sizeof (fh));
4224 	return (error);
4225 }
4226 
4227 #ifndef _SYS_SYSPROTO_H_
4228 struct fhlink_args {
4229 	fhandle_t *fhp;
4230 	const char *to;
4231 };
4232 #endif
4233 int
sys_fhlink(struct thread * td,struct fhlink_args * uap)4234 sys_fhlink(struct thread *td, struct fhlink_args *uap)
4235 {
4236 
4237 	return (kern_fhlinkat(td, AT_FDCWD, uap->to, UIO_USERSPACE, uap->fhp));
4238 }
4239 
4240 #ifndef _SYS_SYSPROTO_H_
4241 struct fhlinkat_args {
4242 	fhandle_t *fhp;
4243 	int tofd;
4244 	const char *to;
4245 };
4246 #endif
4247 int
sys_fhlinkat(struct thread * td,struct fhlinkat_args * uap)4248 sys_fhlinkat(struct thread *td, struct fhlinkat_args *uap)
4249 {
4250 
4251 	return (kern_fhlinkat(td, uap->tofd, uap->to, UIO_USERSPACE, uap->fhp));
4252 }
4253 
4254 static int
kern_fhlinkat(struct thread * td,int fd,const char * path,enum uio_seg pathseg,fhandle_t * fhp)4255 kern_fhlinkat(struct thread *td, int fd, const char *path,
4256     enum uio_seg pathseg, fhandle_t *fhp)
4257 {
4258 	fhandle_t fh;
4259 	struct mount *mp;
4260 	struct vnode *vp;
4261 	int error;
4262 
4263 	error = priv_check(td, PRIV_VFS_GETFH);
4264 	if (error != 0)
4265 		return (error);
4266 	error = copyin(fhp, &fh, sizeof(fh));
4267 	if (error != 0)
4268 		return (error);
4269 	do {
4270 		bwillwrite();
4271 		if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
4272 			return (ESTALE);
4273 		error = VFS_FHTOVP(mp, &fh.fh_fid, LK_SHARED, &vp);
4274 		vfs_unbusy(mp);
4275 		if (error != 0)
4276 			return (error);
4277 		VOP_UNLOCK(vp, 0);
4278 	} while ((error = kern_linkat_vp(td, vp, fd, path, pathseg)) == EAGAIN);
4279 	return (error);
4280 }
4281 
4282 #ifndef _SYS_SYSPROTO_H_
4283 struct fhreadlink_args {
4284 	fhandle_t *fhp;
4285 	char *buf;
4286 	size_t bufsize;
4287 };
4288 #endif
4289 int
sys_fhreadlink(struct thread * td,struct fhreadlink_args * uap)4290 sys_fhreadlink(struct thread *td, struct fhreadlink_args *uap)
4291 {
4292 	fhandle_t fh;
4293 	struct mount *mp;
4294 	struct vnode *vp;
4295 	int error;
4296 
4297 	error = priv_check(td, PRIV_VFS_GETFH);
4298 	if (error != 0)
4299 		return (error);
4300 	if (uap->bufsize > IOSIZE_MAX)
4301 		return (EINVAL);
4302 	error = copyin(uap->fhp, &fh, sizeof(fh));
4303 	if (error != 0)
4304 		return (error);
4305 	if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
4306 		return (ESTALE);
4307 	error = VFS_FHTOVP(mp, &fh.fh_fid, LK_SHARED, &vp);
4308 	vfs_unbusy(mp);
4309 	if (error != 0)
4310 		return (error);
4311 	error = kern_readlink_vp(vp, uap->buf, UIO_USERSPACE, uap->bufsize, td);
4312 	vput(vp);
4313 	return (error);
4314 }
4315 
4316 /*
4317  * syscall for the rpc.lockd to use to translate a NFS file handle into an
4318  * open descriptor.
4319  *
4320  * warning: do not remove the priv_check() call or this becomes one giant
4321  * security hole.
4322  */
4323 #ifndef _SYS_SYSPROTO_H_
4324 struct fhopen_args {
4325 	const struct fhandle *u_fhp;
4326 	int flags;
4327 };
4328 #endif
4329 int
sys_fhopen(struct thread * td,struct fhopen_args * uap)4330 sys_fhopen(struct thread *td, struct fhopen_args *uap)
4331 {
4332 	struct mount *mp;
4333 	struct vnode *vp;
4334 	struct fhandle fhp;
4335 	struct file *fp;
4336 	int fmode, error;
4337 	int indx;
4338 
4339 	error = priv_check(td, PRIV_VFS_FHOPEN);
4340 	if (error != 0)
4341 		return (error);
4342 	indx = -1;
4343 	fmode = FFLAGS(uap->flags);
4344 	/* why not allow a non-read/write open for our lockd? */
4345 	if (((fmode & (FREAD | FWRITE)) == 0) || (fmode & O_CREAT))
4346 		return (EINVAL);
4347 	error = copyin(uap->u_fhp, &fhp, sizeof(fhp));
4348 	if (error != 0)
4349 		return(error);
4350 	/* find the mount point */
4351 	mp = vfs_busyfs(&fhp.fh_fsid);
4352 	if (mp == NULL)
4353 		return (ESTALE);
4354 	/* now give me my vnode, it gets returned to me locked */
4355 	error = VFS_FHTOVP(mp, &fhp.fh_fid, LK_EXCLUSIVE, &vp);
4356 	vfs_unbusy(mp);
4357 	if (error != 0)
4358 		return (error);
4359 
4360 	error = falloc_noinstall(td, &fp);
4361 	if (error != 0) {
4362 		vput(vp);
4363 		return (error);
4364 	}
4365 	/*
4366 	 * An extra reference on `fp' has been held for us by
4367 	 * falloc_noinstall().
4368 	 */
4369 
4370 #ifdef INVARIANTS
4371 	td->td_dupfd = -1;
4372 #endif
4373 	error = vn_open_vnode(vp, fmode, td->td_ucred, td, fp);
4374 	if (error != 0) {
4375 		KASSERT(fp->f_ops == &badfileops,
4376 		    ("VOP_OPEN in fhopen() set f_ops"));
4377 		KASSERT(td->td_dupfd < 0,
4378 		    ("fhopen() encountered fdopen()"));
4379 
4380 		vput(vp);
4381 		goto bad;
4382 	}
4383 #ifdef INVARIANTS
4384 	td->td_dupfd = 0;
4385 #endif
4386 	fp->f_vnode = vp;
4387 	fp->f_seqcount = 1;
4388 	finit(fp, (fmode & FMASK) | (fp->f_flag & FHASLOCK), DTYPE_VNODE, vp,
4389 	    &vnops);
4390 	VOP_UNLOCK(vp, 0);
4391 	if ((fmode & O_TRUNC) != 0) {
4392 		error = fo_truncate(fp, 0, td->td_ucred, td);
4393 		if (error != 0)
4394 			goto bad;
4395 	}
4396 
4397 	error = finstall(td, fp, &indx, fmode, NULL);
4398 bad:
4399 	fdrop(fp, td);
4400 	td->td_retval[0] = indx;
4401 	return (error);
4402 }
4403 
4404 /*
4405  * Stat an (NFS) file handle.
4406  */
4407 #ifndef _SYS_SYSPROTO_H_
4408 struct fhstat_args {
4409 	struct fhandle *u_fhp;
4410 	struct stat *sb;
4411 };
4412 #endif
4413 int
sys_fhstat(struct thread * td,struct fhstat_args * uap)4414 sys_fhstat(struct thread *td, struct fhstat_args *uap)
4415 {
4416 	struct stat sb;
4417 	struct fhandle fh;
4418 	int error;
4419 
4420 	error = copyin(uap->u_fhp, &fh, sizeof(fh));
4421 	if (error != 0)
4422 		return (error);
4423 	error = kern_fhstat(td, fh, &sb);
4424 	if (error == 0)
4425 		error = copyout(&sb, uap->sb, sizeof(sb));
4426 	return (error);
4427 }
4428 
4429 int
kern_fhstat(struct thread * td,struct fhandle fh,struct stat * sb)4430 kern_fhstat(struct thread *td, struct fhandle fh, struct stat *sb)
4431 {
4432 	struct mount *mp;
4433 	struct vnode *vp;
4434 	int error;
4435 
4436 	error = priv_check(td, PRIV_VFS_FHSTAT);
4437 	if (error != 0)
4438 		return (error);
4439 	if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
4440 		return (ESTALE);
4441 	error = VFS_FHTOVP(mp, &fh.fh_fid, LK_EXCLUSIVE, &vp);
4442 	vfs_unbusy(mp);
4443 	if (error != 0)
4444 		return (error);
4445 	error = vn_stat(vp, sb, td->td_ucred, NOCRED, td);
4446 	vput(vp);
4447 	return (error);
4448 }
4449 
4450 /*
4451  * Implement fstatfs() for (NFS) file handles.
4452  */
4453 #ifndef _SYS_SYSPROTO_H_
4454 struct fhstatfs_args {
4455 	struct fhandle *u_fhp;
4456 	struct statfs *buf;
4457 };
4458 #endif
4459 int
sys_fhstatfs(struct thread * td,struct fhstatfs_args * uap)4460 sys_fhstatfs(struct thread *td, struct fhstatfs_args *uap)
4461 {
4462 	struct statfs *sfp;
4463 	fhandle_t fh;
4464 	int error;
4465 
4466 	error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
4467 	if (error != 0)
4468 		return (error);
4469 	sfp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK);
4470 	error = kern_fhstatfs(td, fh, sfp);
4471 	if (error == 0)
4472 		error = copyout(sfp, uap->buf, sizeof(*sfp));
4473 	free(sfp, M_STATFS);
4474 	return (error);
4475 }
4476 
4477 int
kern_fhstatfs(struct thread * td,fhandle_t fh,struct statfs * buf)4478 kern_fhstatfs(struct thread *td, fhandle_t fh, struct statfs *buf)
4479 {
4480 	struct statfs *sp;
4481 	struct mount *mp;
4482 	struct vnode *vp;
4483 	int error;
4484 
4485 	error = priv_check(td, PRIV_VFS_FHSTATFS);
4486 	if (error != 0)
4487 		return (error);
4488 	if ((mp = vfs_busyfs(&fh.fh_fsid)) == NULL)
4489 		return (ESTALE);
4490 	error = VFS_FHTOVP(mp, &fh.fh_fid, LK_EXCLUSIVE, &vp);
4491 	if (error != 0) {
4492 		vfs_unbusy(mp);
4493 		return (error);
4494 	}
4495 	vput(vp);
4496 	error = prison_canseemount(td->td_ucred, mp);
4497 	if (error != 0)
4498 		goto out;
4499 #ifdef MAC
4500 	error = mac_mount_check_stat(td->td_ucred, mp);
4501 	if (error != 0)
4502 		goto out;
4503 #endif
4504 	/*
4505 	 * Set these in case the underlying filesystem fails to do so.
4506 	 */
4507 	sp = &mp->mnt_stat;
4508 	sp->f_version = STATFS_VERSION;
4509 	sp->f_namemax = NAME_MAX;
4510 	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
4511 	error = VFS_STATFS(mp, sp);
4512 	if (error == 0)
4513 		*buf = *sp;
4514 out:
4515 	vfs_unbusy(mp);
4516 	return (error);
4517 }
4518 
4519 int
kern_posix_fallocate(struct thread * td,int fd,off_t offset,off_t len)4520 kern_posix_fallocate(struct thread *td, int fd, off_t offset, off_t len)
4521 {
4522 	struct file *fp;
4523 	struct mount *mp;
4524 	struct vnode *vp;
4525 	off_t olen, ooffset;
4526 	int error;
4527 #ifdef AUDIT
4528 	int audited_vnode1 = 0;
4529 #endif
4530 
4531 	AUDIT_ARG_FD(fd);
4532 	if (offset < 0 || len <= 0)
4533 		return (EINVAL);
4534 	/* Check for wrap. */
4535 	if (offset > OFF_MAX - len)
4536 		return (EFBIG);
4537 	AUDIT_ARG_FD(fd);
4538 	error = fget(td, fd, &cap_pwrite_rights, &fp);
4539 	if (error != 0)
4540 		return (error);
4541 	AUDIT_ARG_FILE(td->td_proc, fp);
4542 	if ((fp->f_ops->fo_flags & DFLAG_SEEKABLE) == 0) {
4543 		error = ESPIPE;
4544 		goto out;
4545 	}
4546 	if ((fp->f_flag & FWRITE) == 0) {
4547 		error = EBADF;
4548 		goto out;
4549 	}
4550 	if (fp->f_type != DTYPE_VNODE) {
4551 		error = ENODEV;
4552 		goto out;
4553 	}
4554 	vp = fp->f_vnode;
4555 	if (vp->v_type != VREG) {
4556 		error = ENODEV;
4557 		goto out;
4558 	}
4559 
4560 	/* Allocating blocks may take a long time, so iterate. */
4561 	for (;;) {
4562 		olen = len;
4563 		ooffset = offset;
4564 
4565 		bwillwrite();
4566 		mp = NULL;
4567 		error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
4568 		if (error != 0)
4569 			break;
4570 		error = vn_lock(vp, LK_EXCLUSIVE);
4571 		if (error != 0) {
4572 			vn_finished_write(mp);
4573 			break;
4574 		}
4575 #ifdef AUDIT
4576 		if (!audited_vnode1) {
4577 			AUDIT_ARG_VNODE1(vp);
4578 			audited_vnode1 = 1;
4579 		}
4580 #endif
4581 #ifdef MAC
4582 		error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
4583 		if (error == 0)
4584 #endif
4585 			error = VOP_ALLOCATE(vp, &offset, &len);
4586 		VOP_UNLOCK(vp, 0);
4587 		vn_finished_write(mp);
4588 
4589 		if (olen + ooffset != offset + len) {
4590 			panic("offset + len changed from %jx/%jx to %jx/%jx",
4591 			    ooffset, olen, offset, len);
4592 		}
4593 		if (error != 0 || len == 0)
4594 			break;
4595 		KASSERT(olen > len, ("Iteration did not make progress?"));
4596 		maybe_yield();
4597 	}
4598  out:
4599 	fdrop(fp, td);
4600 	return (error);
4601 }
4602 
4603 int
sys_posix_fallocate(struct thread * td,struct posix_fallocate_args * uap)4604 sys_posix_fallocate(struct thread *td, struct posix_fallocate_args *uap)
4605 {
4606 	int error;
4607 
4608 	error = kern_posix_fallocate(td, uap->fd, uap->offset, uap->len);
4609 	return (kern_posix_error(td, error));
4610 }
4611 
4612 /*
4613  * Unlike madvise(2), we do not make a best effort to remember every
4614  * possible caching hint.  Instead, we remember the last setting with
4615  * the exception that we will allow POSIX_FADV_NORMAL to adjust the
4616  * region of any current setting.
4617  */
4618 int
kern_posix_fadvise(struct thread * td,int fd,off_t offset,off_t len,int advice)4619 kern_posix_fadvise(struct thread *td, int fd, off_t offset, off_t len,
4620     int advice)
4621 {
4622 	struct fadvise_info *fa, *new;
4623 	struct file *fp;
4624 	struct vnode *vp;
4625 	off_t end;
4626 	int error;
4627 
4628 	if (offset < 0 || len < 0 || offset > OFF_MAX - len)
4629 		return (EINVAL);
4630 	AUDIT_ARG_VALUE(advice);
4631 	switch (advice) {
4632 	case POSIX_FADV_SEQUENTIAL:
4633 	case POSIX_FADV_RANDOM:
4634 	case POSIX_FADV_NOREUSE:
4635 		new = malloc(sizeof(*fa), M_FADVISE, M_WAITOK);
4636 		break;
4637 	case POSIX_FADV_NORMAL:
4638 	case POSIX_FADV_WILLNEED:
4639 	case POSIX_FADV_DONTNEED:
4640 		new = NULL;
4641 		break;
4642 	default:
4643 		return (EINVAL);
4644 	}
4645 	/* XXX: CAP_POSIX_FADVISE? */
4646 	AUDIT_ARG_FD(fd);
4647 	error = fget(td, fd, &cap_no_rights, &fp);
4648 	if (error != 0)
4649 		goto out;
4650 	AUDIT_ARG_FILE(td->td_proc, fp);
4651 	if ((fp->f_ops->fo_flags & DFLAG_SEEKABLE) == 0) {
4652 		error = ESPIPE;
4653 		goto out;
4654 	}
4655 	if (fp->f_type != DTYPE_VNODE) {
4656 		error = ENODEV;
4657 		goto out;
4658 	}
4659 	vp = fp->f_vnode;
4660 	if (vp->v_type != VREG) {
4661 		error = ENODEV;
4662 		goto out;
4663 	}
4664 	if (len == 0)
4665 		end = OFF_MAX;
4666 	else
4667 		end = offset + len - 1;
4668 	switch (advice) {
4669 	case POSIX_FADV_SEQUENTIAL:
4670 	case POSIX_FADV_RANDOM:
4671 	case POSIX_FADV_NOREUSE:
4672 		/*
4673 		 * Try to merge any existing non-standard region with
4674 		 * this new region if possible, otherwise create a new
4675 		 * non-standard region for this request.
4676 		 */
4677 		mtx_pool_lock(mtxpool_sleep, fp);
4678 		fa = fp->f_advice;
4679 		if (fa != NULL && fa->fa_advice == advice &&
4680 		    ((fa->fa_start <= end && fa->fa_end >= offset) ||
4681 		    (end != OFF_MAX && fa->fa_start == end + 1) ||
4682 		    (fa->fa_end != OFF_MAX && fa->fa_end + 1 == offset))) {
4683 			if (offset < fa->fa_start)
4684 				fa->fa_start = offset;
4685 			if (end > fa->fa_end)
4686 				fa->fa_end = end;
4687 		} else {
4688 			new->fa_advice = advice;
4689 			new->fa_start = offset;
4690 			new->fa_end = end;
4691 			fp->f_advice = new;
4692 			new = fa;
4693 		}
4694 		mtx_pool_unlock(mtxpool_sleep, fp);
4695 		break;
4696 	case POSIX_FADV_NORMAL:
4697 		/*
4698 		 * If a the "normal" region overlaps with an existing
4699 		 * non-standard region, trim or remove the
4700 		 * non-standard region.
4701 		 */
4702 		mtx_pool_lock(mtxpool_sleep, fp);
4703 		fa = fp->f_advice;
4704 		if (fa != NULL) {
4705 			if (offset <= fa->fa_start && end >= fa->fa_end) {
4706 				new = fa;
4707 				fp->f_advice = NULL;
4708 			} else if (offset <= fa->fa_start &&
4709 			    end >= fa->fa_start)
4710 				fa->fa_start = end + 1;
4711 			else if (offset <= fa->fa_end && end >= fa->fa_end)
4712 				fa->fa_end = offset - 1;
4713 			else if (offset >= fa->fa_start && end <= fa->fa_end) {
4714 				/*
4715 				 * If the "normal" region is a middle
4716 				 * portion of the existing
4717 				 * non-standard region, just remove
4718 				 * the whole thing rather than picking
4719 				 * one side or the other to
4720 				 * preserve.
4721 				 */
4722 				new = fa;
4723 				fp->f_advice = NULL;
4724 			}
4725 		}
4726 		mtx_pool_unlock(mtxpool_sleep, fp);
4727 		break;
4728 	case POSIX_FADV_WILLNEED:
4729 	case POSIX_FADV_DONTNEED:
4730 		error = VOP_ADVISE(vp, offset, end, advice);
4731 		break;
4732 	}
4733 out:
4734 	if (fp != NULL)
4735 		fdrop(fp, td);
4736 	free(new, M_FADVISE);
4737 	return (error);
4738 }
4739 
4740 int
sys_posix_fadvise(struct thread * td,struct posix_fadvise_args * uap)4741 sys_posix_fadvise(struct thread *td, struct posix_fadvise_args *uap)
4742 {
4743 	int error;
4744 
4745 	error = kern_posix_fadvise(td, uap->fd, uap->offset, uap->len,
4746 	    uap->advice);
4747 	return (kern_posix_error(td, error));
4748 }
4749