xref: /titanic_41/usr/src/uts/common/syscall/stat.c (revision 1ae0874509b6811fdde1dfd46f0d93fd09867a3f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #pragma ident	"%Z%%M%	%I%	%E% SMI"
36 
37 /*
38  * Get file attribute information through a file name or a file descriptor.
39  */
40 
41 #include <sys/param.h>
42 #include <sys/isa_defs.h>
43 #include <sys/types.h>
44 #include <sys/sysmacros.h>
45 #include <sys/cred.h>
46 #include <sys/systm.h>
47 #include <sys/errno.h>
48 #include <sys/fcntl.h>
49 #include <sys/pathname.h>
50 #include <sys/stat.h>
51 #include <sys/vfs.h>
52 #include <sys/vnode.h>
53 #include <sys/mode.h>
54 #include <sys/file.h>
55 #include <sys/proc.h>
56 #include <sys/uio.h>
57 #include <sys/debug.h>
58 #include <sys/cmn_err.h>
59 #include <c2/audit.h>
60 
61 /*
62  * Get the vp to be stated and the cred to be used for the call
63  * to VOP_GETATTR
64  */
65 
66 /*
67  * nmflag has the following values
68  *
69  * 1 - Always do lookup.  i.e. stat, lstat.
70  * 2 - Name is optional i.e. fstatat
71  * 0 - Don't lookup name, vp is in file_p. i.e. fstat
72  *
73  */
74 static int
75 cstatat_getvp(int fd, char *name, int nmflag,
76     int follow, vnode_t **vp, cred_t **cred)
77 {
78 	vnode_t *startvp;
79 	file_t *fp;
80 	int error;
81 	cred_t *cr;
82 
83 	*vp = NULL;
84 
85 	/*
86 	 * Only return EFAULT for fstatat when fd == AT_FDCWD && name == NULL
87 	 */
88 
89 	if (fd == AT_FDCWD) {
90 		if (name != NULL || nmflag != 2) {
91 			startvp = NULL;
92 			cr = CRED();
93 			crhold(cr);
94 		} else
95 			return (EFAULT);
96 	} else {
97 		char startchar;
98 
99 		if (nmflag == 1 || (nmflag == 2 && name != NULL)) {
100 			if (copyin(name, &startchar, sizeof (char)))
101 				return (EFAULT);
102 		} else {
103 			startchar = '\0';
104 		}
105 		if (startchar != '/' || nmflag == 0) {
106 			if ((fp = getf(fd)) == NULL) {
107 				return (EBADF);
108 			}
109 			startvp = fp->f_vnode;
110 			cr = fp->f_cred;
111 			crhold(cr);
112 			VN_HOLD(startvp);
113 			releasef(fd);
114 		} else {
115 			startvp = NULL;
116 			cr = CRED();
117 			crhold(cr);
118 		}
119 	}
120 	*cred = cr;
121 
122 #ifdef C2_AUDIT
123 	if (audit_active)
124 		audit_setfsat_path(1);
125 #endif /* C2_AUDIT */
126 
127 
128 	if (nmflag == 1 || (nmflag == 2 && name != NULL)) {
129 lookup:
130 		if (error = lookupnameat(name, UIO_USERSPACE, follow, NULLVPP,
131 		    vp, startvp)) {
132 			if (error == ESTALE)
133 				goto lookup;
134 			if (startvp != NULL)
135 				VN_RELE(startvp);
136 			crfree(cr);
137 			return (error);
138 		}
139 		if (startvp != NULL)
140 			VN_RELE(startvp);
141 	} else {
142 		*vp = startvp;
143 	}
144 
145 	return (0);
146 }
147 
148 /*
149  * Native syscall interfaces:
150  *
151  * N-bit kernel, N-bit applications, N-bit file offsets
152  */
153 
154 static int cstatat(int, char *, int, struct stat *, int, int);
155 static int cstat(vnode_t *vp, struct stat *, int, cred_t *);
156 
157 int
158 stat(char *fname, struct stat *sb)
159 {
160 	return (cstatat(AT_FDCWD, fname, 1, sb, 0, ATTR_REAL));
161 }
162 
163 int
164 lstat(char *fname, struct stat *sb)
165 {
166 	return (cstatat(AT_FDCWD, fname, 1, sb, AT_SYMLINK_NOFOLLOW, 0));
167 }
168 
169 /*
170  * fstat can and should be fast, do an inline implementation here.
171  */
172 #define	FSTAT_BODY(fd, sb, statfn)				\
173 	{							\
174 		file_t *fp;					\
175 		int error;					\
176 								\
177 		if ((fp = getf(fd)) == NULL)			\
178 			return (set_errno(EBADF));		\
179 		if (audit_active)				\
180 			audit_setfsat_path(1);			\
181 		error = statfn(fp->f_vnode, sb, 0, fp->f_cred);	\
182 		releasef(fd);					\
183 		if (error)					\
184 			return (set_errno(error));		\
185 		return (0);					\
186 	}
187 
188 int
189 fstat(int fd, struct stat *sb)
190 {
191 	FSTAT_BODY(fd, sb, cstat)
192 }
193 
194 int
195 fstatat(int fd, char *name, struct stat *sb, int flags)
196 {
197 	return (cstatat(fd, name, 2, sb, flags, 0));
198 }
199 
200 #if defined(__i386) || defined(__i386_COMPAT)
201 
202 /*
203  * Handle all the "extended" stat operations in the same way;
204  * validate the version, then call the real handler.
205  */
206 
207 #define	XSTAT_BODY(ver, f, s, fn)			\
208 	return (ver != _STAT_VER ? set_errno(EINVAL) : fn(f, s));
209 
210 #endif	/* __i386 || __i386_COMPAT */
211 
212 #if defined(__i386)
213 
214 /*
215  * Syscalls for i386 applications that issue {,l,f}xstat() directly
216  */
217 int
218 xstat(int version, char *fname, struct stat *sb)
219 {
220 	XSTAT_BODY(version, fname, sb, stat)
221 }
222 
223 int
224 lxstat(int version, char *fname, struct stat *sb)
225 {
226 	XSTAT_BODY(version, fname, sb, lstat)
227 }
228 
229 int
230 fxstat(int version, int fd, struct stat *sb)
231 {
232 	XSTAT_BODY(version, fd, sb, fstat)
233 }
234 
235 #endif	/* __i386 */
236 
237 /*
238  * Common code for stat(), lstat(), and fstat().
239  * (32-bit kernel, 32-bit applications, 32-bit files)
240  * (64-bit kernel, 64-bit applications, 64-bit files)
241  */
242 static int
243 cstat(vnode_t *vp, struct stat *ubp, int flag, cred_t *cr)
244 {
245 	struct vfssw *vswp;
246 	struct stat sb;
247 	vattr_t vattr;
248 	int error;
249 
250 	vattr.va_mask = AT_STAT | AT_NBLOCKS | AT_BLKSIZE | AT_SIZE;
251 	if ((error = VOP_GETATTR(vp, &vattr, flag, cr)) != 0)
252 		return (error);
253 #ifdef	_ILP32
254 	/*
255 	 * (32-bit kernel, 32-bit applications, 32-bit files)
256 	 * NOTE: 32-bit kernel maintains a 64-bit unsigend va_size.
257 	 *
258 	 * st_size of devices (VBLK and VCHR special files) is a special case.
259 	 * POSIX does not define size behavior for special files, so the
260 	 * following Solaris specific behavior is not a violation. Solaris
261 	 * returns the size of the device.
262 	 *
263 	 * For compatibility with 32-bit programs which happen to do stat() on
264 	 * a (mknod) bigger than 2GB we suppress the large file EOVERFLOW and
265 	 * instead we return the value MAXOFF32_T (LONG_MAX).
266 	 *
267 	 * 32-bit applications that care about the size of devices should be
268 	 * built 64-bit or use a large file interface (lfcompile(5) or lf64(5)).
269 	 */
270 	if ((vattr.va_size > MAXOFF32_T) &&
271 	    ((vp->v_type == VBLK) || (vp->v_type == VCHR))) {
272 		/* OVERFLOW | UNKNOWN_SIZE */
273 		vattr.va_size = MAXOFF32_T;
274 	}
275 #endif	/* _ILP32 */
276 	if (vattr.va_size > MAXOFF_T || vattr.va_nblocks > LONG_MAX ||
277 	    vattr.va_nodeid > ULONG_MAX)
278 		return (EOVERFLOW);
279 
280 	bzero(&sb, sizeof (sb));
281 	sb.st_dev = vattr.va_fsid;
282 	sb.st_ino = (ino_t)vattr.va_nodeid;
283 	sb.st_mode = VTTOIF(vattr.va_type) | vattr.va_mode;
284 	sb.st_nlink = vattr.va_nlink;
285 	sb.st_uid = vattr.va_uid;
286 	sb.st_gid = vattr.va_gid;
287 	sb.st_rdev = vattr.va_rdev;
288 	sb.st_size = (off_t)vattr.va_size;
289 	sb.st_atim = vattr.va_atime;
290 	sb.st_mtim = vattr.va_mtime;
291 	sb.st_ctim = vattr.va_ctime;
292 	sb.st_blksize = vattr.va_blksize;
293 	sb.st_blocks = (blkcnt_t)vattr.va_nblocks;
294 	if (vp->v_vfsp != NULL) {
295 		vswp = &vfssw[vp->v_vfsp->vfs_fstype];
296 		if (vswp->vsw_name && *vswp->vsw_name)
297 			(void) strcpy(sb.st_fstype, vswp->vsw_name);
298 	}
299 	if (copyout(&sb, ubp, sizeof (sb)))
300 		return (EFAULT);
301 	return (0);
302 }
303 
304 static int
305 cstatat(int fd, char *name, int nmflag, struct stat *sb, int follow, int flags)
306 {
307 	vnode_t *vp;
308 	int error;
309 	cred_t *cred;
310 	int link_follow;
311 
312 	link_follow = (follow == AT_SYMLINK_NOFOLLOW) ? NO_FOLLOW : FOLLOW;
313 lookup:
314 	if (error = cstatat_getvp(fd, name, nmflag, link_follow, &vp, &cred))
315 		return (set_errno(error));
316 	error = cstat(vp, sb, flags, cred);
317 	crfree(cred);
318 	VN_RELE(vp);
319 out:
320 	if (error != 0) {
321 		if (error == ESTALE &&
322 		    (nmflag == 1 || (nmflag == 2 && name != NULL)))
323 			goto lookup;
324 		return (set_errno(error));
325 	}
326 	return (0);
327 }
328 
329 #if defined(_SYSCALL32_IMPL)
330 
331 /*
332  * 64-bit kernel, 32-bit applications, 32-bit file offsets
333  */
334 static int cstatat32(int, char *, int, struct stat32 *, int, int);
335 static int cstat32(vnode_t *, struct stat32 *, int, cred_t *);
336 
337 int
338 stat32(char *fname, struct stat32 *sb)
339 {
340 	return (cstatat32(AT_FDCWD, fname, 1, sb, 0, ATTR_REAL));
341 }
342 
343 int
344 lstat32(char *fname, struct stat32 *sb)
345 {
346 	return (cstatat32(AT_FDCWD, fname, 1, sb, AT_SYMLINK_NOFOLLOW, 0));
347 }
348 
349 int
350 fstat32(int fd, struct stat32 *sb)
351 {
352 	FSTAT_BODY(fd, sb, cstat32)
353 }
354 
355 int
356 fstatat32(int fd, char *name, struct stat32 *sb, int flag)
357 {
358 	return (cstatat32(fd, name, 2, sb, flag, 0));
359 }
360 
361 #if defined(__i386_COMPAT)
362 
363 /*
364  * Syscalls for i386 applications that issue {,l,f}xstat() directly
365  */
366 int
367 xstat32(int version, char *fname, struct stat32 *sb)
368 {
369 	XSTAT_BODY(version, fname, sb, stat32)
370 }
371 
372 int
373 lxstat32(int version, char *fname, struct stat32 *sb)
374 {
375 	XSTAT_BODY(version, fname, sb, lstat32)
376 }
377 
378 int
379 fxstat32(int version, int fd, struct stat32 *sb)
380 {
381 	XSTAT_BODY(version, fd, sb, fstat32)
382 }
383 
384 #endif	/* __i386_COMPAT */
385 
386 static int
387 cstat32(vnode_t *vp, struct stat32 *ubp, int flag, struct cred *cr)
388 {
389 	struct vfssw *vswp;
390 	struct stat32 sb;
391 	vattr_t vattr;
392 	int error;
393 	dev32_t st_dev, st_rdev;
394 
395 	vattr.va_mask = AT_STAT | AT_NBLOCKS | AT_BLKSIZE | AT_SIZE;
396 	if (error = VOP_GETATTR(vp, &vattr, flag, cr))
397 		return (error);
398 
399 	/* devices are a special case, see comments in cstat */
400 	if ((vattr.va_size > MAXOFF32_T) &&
401 	    ((vp->v_type == VBLK) || (vp->v_type == VCHR))) {
402 		/* OVERFLOW | UNKNOWN_SIZE */
403 		vattr.va_size = MAXOFF32_T;
404 	}
405 
406 	/* check for large values */
407 	if (!cmpldev(&st_dev, vattr.va_fsid) ||
408 	    !cmpldev(&st_rdev, vattr.va_rdev) ||
409 	    vattr.va_size > MAXOFF32_T ||
410 	    vattr.va_nblocks > INT32_MAX ||
411 	    vattr.va_nodeid > UINT32_MAX ||
412 	    TIMESPEC_OVERFLOW(&(vattr.va_atime)) ||
413 	    TIMESPEC_OVERFLOW(&(vattr.va_mtime)) ||
414 	    TIMESPEC_OVERFLOW(&(vattr.va_ctime)))
415 		return (EOVERFLOW);
416 
417 	bzero(&sb, sizeof (sb));
418 	sb.st_dev = st_dev;
419 	sb.st_ino = (ino32_t)vattr.va_nodeid;
420 	sb.st_mode = VTTOIF(vattr.va_type) | vattr.va_mode;
421 	sb.st_nlink = vattr.va_nlink;
422 	sb.st_uid = vattr.va_uid;
423 	sb.st_gid = vattr.va_gid;
424 	sb.st_rdev = st_rdev;
425 	sb.st_size = (off32_t)vattr.va_size;
426 	TIMESPEC_TO_TIMESPEC32(&(sb.st_atim), &(vattr.va_atime));
427 	TIMESPEC_TO_TIMESPEC32(&(sb.st_mtim), &(vattr.va_mtime));
428 	TIMESPEC_TO_TIMESPEC32(&(sb.st_ctim), &(vattr.va_ctime));
429 	sb.st_blksize = vattr.va_blksize;
430 	sb.st_blocks = (blkcnt32_t)vattr.va_nblocks;
431 	if (vp->v_vfsp != NULL) {
432 		vswp = &vfssw[vp->v_vfsp->vfs_fstype];
433 		if (vswp->vsw_name && *vswp->vsw_name)
434 			(void) strcpy(sb.st_fstype, vswp->vsw_name);
435 	}
436 	if (copyout(&sb, ubp, sizeof (sb)))
437 		return (EFAULT);
438 	return (0);
439 }
440 
441 static int
442 cstatat32(int fd, char *name, int nmflag, struct stat32 *sb,
443     int follow, int flags)
444 {
445 	vnode_t *vp;
446 	int error;
447 	cred_t *cred;
448 	int link_follow;
449 
450 	link_follow = (follow == AT_SYMLINK_NOFOLLOW) ? NO_FOLLOW : FOLLOW;
451 lookup:
452 	if (error = cstatat_getvp(fd, name, nmflag, link_follow, &vp, &cred))
453 		return (set_errno(error));
454 	error = cstat32(vp, sb, flags, cred);
455 	crfree(cred);
456 	VN_RELE(vp);
457 out:
458 	if (error != 0) {
459 		if (error == ESTALE &&
460 		    (nmflag == 1 || (nmflag == 2 && name != NULL)))
461 			goto lookup;
462 		return (set_errno(error));
463 	}
464 	return (0);
465 }
466 
467 #endif	/* _SYSCALL32_IMPL */
468 
469 #if defined(_ILP32)
470 
471 /*
472  * 32-bit kernel, 32-bit applications, 64-bit file offsets.
473  *
474  * These routines are implemented differently on 64-bit kernels.
475  */
476 static int cstatat64(int, char *, int, struct stat64 *, int, int);
477 static int cstat64(vnode_t *, struct stat64 *, int, cred_t *);
478 
479 int
480 stat64(char *fname, struct stat64 *sb)
481 {
482 	return (cstatat64(AT_FDCWD, fname, 1, sb, 0, ATTR_REAL));
483 }
484 
485 int
486 lstat64(char *fname, struct stat64 *sb)
487 {
488 	return (cstatat64(AT_FDCWD, fname, 1, sb, AT_SYMLINK_NOFOLLOW, 0));
489 }
490 
491 int
492 fstat64(int fd, struct stat64 *sb)
493 {
494 	FSTAT_BODY(fd, sb, cstat64)
495 }
496 
497 int
498 fstatat64(int fd, char *name, struct stat64 *sb, int flags)
499 {
500 	return (cstatat64(fd, name, 2, sb, flags, 0));
501 }
502 
503 static int
504 cstat64(vnode_t *vp, struct stat64 *ubp, int flag, cred_t *cr)
505 {
506 	struct vfssw *vswp;
507 	struct stat64 lsb;
508 	vattr_t vattr;
509 	int error;
510 
511 	vattr.va_mask = AT_STAT | AT_NBLOCKS | AT_BLKSIZE | AT_SIZE;
512 	if (error = VOP_GETATTR(vp, &vattr, flag, cr))
513 		return (error);
514 
515 	bzero(&lsb, sizeof (lsb));
516 	lsb.st_dev = vattr.va_fsid;
517 	lsb.st_ino = vattr.va_nodeid;
518 	lsb.st_mode = VTTOIF(vattr.va_type) | vattr.va_mode;
519 	lsb.st_nlink = vattr.va_nlink;
520 	lsb.st_uid = vattr.va_uid;
521 	lsb.st_gid = vattr.va_gid;
522 	lsb.st_rdev = vattr.va_rdev;
523 	lsb.st_size = vattr.va_size;
524 	lsb.st_atim = vattr.va_atime;
525 	lsb.st_mtim = vattr.va_mtime;
526 	lsb.st_ctim = vattr.va_ctime;
527 	lsb.st_blksize = vattr.va_blksize;
528 	lsb.st_blocks = vattr.va_nblocks;
529 	if (vp->v_vfsp != NULL) {
530 		vswp = &vfssw[vp->v_vfsp->vfs_fstype];
531 		if (vswp->vsw_name && *vswp->vsw_name)
532 			(void) strcpy(lsb.st_fstype, vswp->vsw_name);
533 	}
534 	if (copyout(&lsb, ubp, sizeof (lsb)))
535 		return (EFAULT);
536 	return (0);
537 }
538 
539 static int
540 cstatat64(int fd, char *name, int nmflag, struct stat64 *sb,
541     int follow, int flags)
542 {
543 	vnode_t *vp;
544 	int error;
545 	cred_t *cred;
546 	int link_follow;
547 
548 	link_follow = (follow == AT_SYMLINK_NOFOLLOW) ? NO_FOLLOW : FOLLOW;
549 lookup:
550 	if (error = cstatat_getvp(fd, name, nmflag, link_follow, &vp, &cred))
551 		return (set_errno(error));
552 	error = cstat64(vp, sb, flags, cred);
553 	crfree(cred);
554 	VN_RELE(vp);
555 out:
556 	if (error != 0) {
557 		if (error == ESTALE &&
558 		    (nmflag == 1 || (nmflag == 2 && name != NULL)))
559 			goto lookup;
560 		return (set_errno(error));
561 	}
562 	return (0);
563 }
564 
565 #endif	/* _ILP32 */
566 
567 #if defined(_SYSCALL32_IMPL)
568 
569 /*
570  * 64-bit kernel, 32-bit applications, 64-bit file offsets.
571  *
572  * We'd really like to call the "native" stat calls for these ones,
573  * but the problem is that the 64-bit ABI defines the 'stat64' structure
574  * differently from the way the 32-bit ABI defines it.
575  */
576 
577 static int cstatat64_32(int, char *, int, struct stat64_32 *, int, int);
578 static int cstat64_32(vnode_t *, struct stat64_32 *, int, cred_t *);
579 
580 int
581 stat64_32(char *fname, struct stat64_32 *sb)
582 {
583 	return (cstatat64_32(AT_FDCWD, fname, 1, sb, 0, ATTR_REAL));
584 }
585 
586 int
587 lstat64_32(char *fname, struct stat64_32 *sb)
588 {
589 	return (cstatat64_32(AT_FDCWD, fname, 1, sb, AT_SYMLINK_NOFOLLOW, 0));
590 }
591 
592 int
593 fstat64_32(int fd, struct stat64_32 *sb)
594 {
595 	FSTAT_BODY(fd, sb, cstat64_32)
596 }
597 
598 int
599 fstatat64_32(int fd, char *name, struct stat64_32 *sb, int flag)
600 {
601 	return (cstatat64_32(fd, name, 2, sb, flag, 0));
602 }
603 
604 static int
605 cstat64_32(vnode_t *vp, struct stat64_32 *ubp, int flag, cred_t *cr)
606 {
607 	struct vfssw *vswp;
608 	struct stat64_32 lsb;
609 	vattr_t vattr;
610 	int error;
611 	dev32_t st_dev, st_rdev;
612 
613 	vattr.va_mask = AT_STAT | AT_NBLOCKS | AT_BLKSIZE | AT_SIZE;
614 	if (error = VOP_GETATTR(vp, &vattr, flag, cr))
615 		return (error);
616 
617 	if (!cmpldev(&st_dev, vattr.va_fsid) ||
618 	    !cmpldev(&st_rdev, vattr.va_rdev) ||
619 	    TIMESPEC_OVERFLOW(&(vattr.va_atime)) ||
620 	    TIMESPEC_OVERFLOW(&(vattr.va_mtime)) ||
621 	    TIMESPEC_OVERFLOW(&(vattr.va_ctime)))
622 		return (EOVERFLOW);
623 
624 	bzero(&lsb, sizeof (lsb));
625 	lsb.st_dev = st_dev;
626 	lsb.st_ino = vattr.va_nodeid;
627 	lsb.st_mode = VTTOIF(vattr.va_type) | vattr.va_mode;
628 	lsb.st_nlink = vattr.va_nlink;
629 	lsb.st_uid = vattr.va_uid;
630 	lsb.st_gid = vattr.va_gid;
631 	lsb.st_rdev = st_rdev;
632 	lsb.st_size = vattr.va_size;
633 	TIMESPEC_TO_TIMESPEC32(&(lsb.st_atim), &(vattr.va_atime));
634 	TIMESPEC_TO_TIMESPEC32(&(lsb.st_mtim), &(vattr.va_mtime));
635 	TIMESPEC_TO_TIMESPEC32(&(lsb.st_ctim), &(vattr.va_ctime));
636 	lsb.st_blksize = vattr.va_blksize;
637 	lsb.st_blocks = vattr.va_nblocks;
638 	if (vp->v_vfsp != NULL) {
639 		vswp = &vfssw[vp->v_vfsp->vfs_fstype];
640 		if (vswp->vsw_name && *vswp->vsw_name)
641 			(void) strcpy(lsb.st_fstype, vswp->vsw_name);
642 	}
643 	if (copyout(&lsb, ubp, sizeof (lsb)))
644 		return (EFAULT);
645 	return (0);
646 }
647 
648 static int
649 cstatat64_32(int fd, char *name, int nmflag, struct stat64_32 *sb,
650     int follow, int flags)
651 {
652 	vnode_t  *vp;
653 	int error;
654 	cred_t *cred;
655 	int link_follow;
656 
657 	link_follow = (follow == AT_SYMLINK_NOFOLLOW) ? NO_FOLLOW : FOLLOW;
658 lookup:
659 	if (error = cstatat_getvp(fd, name, nmflag, link_follow, &vp, &cred))
660 		return (set_errno(error));
661 	error = cstat64_32(vp, sb, flags, cred);
662 	crfree(cred);
663 	VN_RELE(vp);
664 out:
665 	if (error != 0) {
666 		if (error == ESTALE &&
667 		    (nmflag == 1 || (nmflag == 2 && name != NULL)))
668 			goto lookup;
669 		return (set_errno(error));
670 	}
671 	return (0);
672 }
673 
674 #endif /* _SYSCALL32_IMPL */
675