xref: /illumos-gate/usr/src/uts/common/syscall/fcntl.c (revision f6da83d4178694e7113b71d1e452f15b296f73d8)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /* ONC_PLUS EXTRACT START */
23 /*
24  * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
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 /* ONC_PLUS EXTRACT END */
36 
37 #include <sys/param.h>
38 #include <sys/isa_defs.h>
39 #include <sys/types.h>
40 #include <sys/sysmacros.h>
41 #include <sys/systm.h>
42 #include <sys/errno.h>
43 #include <sys/fcntl.h>
44 /* ONC_PLUS EXTRACT START */
45 #include <sys/flock.h>
46 /* ONC_PLUS EXTRACT END */
47 #include <sys/vnode.h>
48 #include <sys/file.h>
49 #include <sys/mode.h>
50 #include <sys/proc.h>
51 #include <sys/filio.h>
52 #include <sys/share.h>
53 #include <sys/debug.h>
54 #include <sys/rctl.h>
55 #include <sys/nbmlock.h>
56 
57 #include <sys/cmn_err.h>
58 
59 /* ONC_PLUS EXTRACT START */
60 static int flock_check(vnode_t *, flock64_t *, offset_t, offset_t);
61 static int flock_get_start(vnode_t *, flock64_t *, offset_t, u_offset_t *);
62 static void fd_too_big(proc_t *);
63 
64 /*
65  * File control.
66  */
67 int
68 fcntl(int fdes, int cmd, intptr_t arg)
69 {
70 	int iarg;
71 	int error = 0;
72 	int retval;
73 	proc_t *p;
74 	file_t *fp;
75 	vnode_t *vp;
76 	u_offset_t offset;
77 	u_offset_t start;
78 	struct vattr vattr;
79 	int in_crit;
80 	int flag;
81 	struct flock sbf;
82 	struct flock64 bf;
83 	struct o_flock obf;
84 	struct flock64_32 bf64_32;
85 	struct fshare fsh;
86 	struct shrlock shr;
87 	struct shr_locowner shr_own;
88 	offset_t maxoffset;
89 	model_t datamodel;
90 	int fdres;
91 
92 #if defined(_ILP32) && !defined(lint) && defined(_SYSCALL32)
93 	ASSERT(sizeof (struct flock) == sizeof (struct flock32));
94 	ASSERT(sizeof (struct flock64) == sizeof (struct flock64_32));
95 #endif
96 #if defined(_LP64) && !defined(lint) && defined(_SYSCALL32)
97 	ASSERT(sizeof (struct flock) == sizeof (struct flock64_64));
98 	ASSERT(sizeof (struct flock64) == sizeof (struct flock64_64));
99 #endif
100 
101 	/*
102 	 * First, for speed, deal with the subset of cases
103 	 * that do not require getf() / releasef().
104 	 */
105 	switch (cmd) {
106 	case F_GETFD:
107 		if ((error = f_getfd_error(fdes, &flag)) == 0)
108 			retval = flag;
109 		goto out;
110 
111 	case F_SETFD:
112 		error = f_setfd_error(fdes, (int)arg);
113 		retval = 0;
114 		goto out;
115 
116 	case F_GETFL:
117 		if ((error = f_getfl(fdes, &flag)) == 0)
118 			retval = (flag & (FMASK | FASYNC)) + FOPEN;
119 		goto out;
120 
121 	case F_GETXFL:
122 		if ((error = f_getfl(fdes, &flag)) == 0)
123 			retval = flag + FOPEN;
124 		goto out;
125 
126 	case F_BADFD:
127 		if ((error = f_badfd(fdes, &fdres, (int)arg)) == 0)
128 			retval = fdres;
129 		goto out;
130 	}
131 
132 	/*
133 	 * Second, for speed, deal with the subset of cases that
134 	 * require getf() / releasef() but do not require copyin.
135 	 */
136 	if ((fp = getf(fdes)) == NULL) {
137 		error = EBADF;
138 		goto out;
139 	}
140 	iarg = (int)arg;
141 
142 	switch (cmd) {
143 /* ONC_PLUS EXTRACT END */
144 
145 	case F_DUPFD:
146 		p = curproc;
147 		if ((uint_t)iarg >= p->p_fno_ctl) {
148 			if (iarg >= 0)
149 				fd_too_big(p);
150 			error = EINVAL;
151 			goto done;
152 		}
153 		/*
154 		 * We need to increment the f_count reference counter
155 		 * before allocating a new file descriptor.
156 		 * Doing it other way round opens a window for race condition
157 		 * with closeandsetf() on the target file descriptor which can
158 		 * close the file still referenced by the original
159 		 * file descriptor.
160 		 */
161 		mutex_enter(&fp->f_tlock);
162 		fp->f_count++;
163 		mutex_exit(&fp->f_tlock);
164 		if ((retval = ufalloc_file(iarg, fp)) == -1) {
165 			/*
166 			 * New file descriptor can't be allocated.
167 			 * Revert the reference count.
168 			 */
169 			mutex_enter(&fp->f_tlock);
170 			fp->f_count--;
171 			mutex_exit(&fp->f_tlock);
172 			error = EMFILE;
173 		}
174 		goto done;
175 
176 	case F_DUP2FD:
177 		p = curproc;
178 		if (fdes == iarg) {
179 			retval = iarg;
180 		} else if ((uint_t)iarg >= p->p_fno_ctl) {
181 			if (iarg >= 0)
182 				fd_too_big(p);
183 			error = EBADF;
184 		} else {
185 			/*
186 			 * We can't hold our getf(fdes) across the call to
187 			 * closeandsetf() because it creates a window for
188 			 * deadlock: if one thread is doing dup2(a, b) while
189 			 * another is doing dup2(b, a), each one will block
190 			 * waiting for the other to call releasef().  The
191 			 * solution is to increment the file reference count
192 			 * (which we have to do anyway), then releasef(fdes),
193 			 * then closeandsetf().  Incrementing f_count ensures
194 			 * that fp won't disappear after we call releasef().
195 			 * When closeandsetf() fails, we try avoid calling
196 			 * closef() because of all the side effects.
197 			 */
198 			mutex_enter(&fp->f_tlock);
199 			fp->f_count++;
200 			mutex_exit(&fp->f_tlock);
201 			releasef(fdes);
202 			if ((error = closeandsetf(iarg, fp)) == 0) {
203 				retval = iarg;
204 			} else {
205 				mutex_enter(&fp->f_tlock);
206 				if (fp->f_count > 1) {
207 					fp->f_count--;
208 					mutex_exit(&fp->f_tlock);
209 				} else {
210 					mutex_exit(&fp->f_tlock);
211 					(void) closef(fp);
212 				}
213 			}
214 			goto out;
215 		}
216 		goto done;
217 
218 	case F_SETFL:
219 		vp = fp->f_vnode;
220 		flag = fp->f_flag;
221 		if ((iarg & (FNONBLOCK|FNDELAY)) == (FNONBLOCK|FNDELAY))
222 			iarg &= ~FNDELAY;
223 		if ((error = VOP_SETFL(vp, flag, iarg, fp->f_cred, NULL)) ==
224 		    0) {
225 			iarg &= FMASK;
226 			mutex_enter(&fp->f_tlock);
227 			fp->f_flag &= ~FMASK | (FREAD|FWRITE);
228 			fp->f_flag |= (iarg - FOPEN) & ~(FREAD|FWRITE);
229 			mutex_exit(&fp->f_tlock);
230 		}
231 		retval = 0;
232 		goto done;
233 	}
234 
235 	/*
236 	 * Finally, deal with the expensive cases.
237 	 */
238 	retval = 0;
239 	in_crit = 0;
240 	maxoffset = MAXOFF_T;
241 	datamodel = DATAMODEL_NATIVE;
242 #if defined(_SYSCALL32_IMPL)
243 	if ((datamodel = get_udatamodel()) == DATAMODEL_ILP32)
244 		maxoffset = MAXOFF32_T;
245 #endif
246 
247 	vp = fp->f_vnode;
248 	flag = fp->f_flag;
249 	offset = fp->f_offset;
250 
251 	switch (cmd) {
252 /* ONC_PLUS EXTRACT START */
253 	/*
254 	 * The file system and vnode layers understand and implement
255 	 * locking with flock64 structures. So here once we pass through
256 	 * the test for compatibility as defined by LFS API, (for F_SETLK,
257 	 * F_SETLKW, F_GETLK, F_GETLKW, F_FREESP) we transform
258 	 * the flock structure to a flock64 structure and send it to the
259 	 * lower layers. Similarly in case of GETLK the returned flock64
260 	 * structure is transformed to a flock structure if everything fits
261 	 * in nicely, otherwise we return EOVERFLOW.
262 	 */
263 
264 	case F_GETLK:
265 	case F_O_GETLK:
266 	case F_SETLK:
267 	case F_SETLKW:
268 	case F_SETLK_NBMAND:
269 
270 		/*
271 		 * Copy in input fields only.
272 		 */
273 
274 		if (cmd == F_O_GETLK) {
275 			if (datamodel != DATAMODEL_ILP32) {
276 				error = EINVAL;
277 				break;
278 			}
279 
280 			if (copyin((void *)arg, &obf, sizeof (obf))) {
281 				error = EFAULT;
282 				break;
283 			}
284 			bf.l_type = obf.l_type;
285 			bf.l_whence = obf.l_whence;
286 			bf.l_start = (off64_t)obf.l_start;
287 			bf.l_len = (off64_t)obf.l_len;
288 			bf.l_sysid = (int)obf.l_sysid;
289 			bf.l_pid = obf.l_pid;
290 		} else if (datamodel == DATAMODEL_NATIVE) {
291 			if (copyin((void *)arg, &sbf, sizeof (sbf))) {
292 				error = EFAULT;
293 				break;
294 			}
295 			/*
296 			 * XXX	In an LP64 kernel with an LP64 application
297 			 *	there's no need to do a structure copy here
298 			 *	struct flock == struct flock64. However,
299 			 *	we did it this way to avoid more conditional
300 			 *	compilation.
301 			 */
302 			bf.l_type = sbf.l_type;
303 			bf.l_whence = sbf.l_whence;
304 			bf.l_start = (off64_t)sbf.l_start;
305 			bf.l_len = (off64_t)sbf.l_len;
306 			bf.l_sysid = sbf.l_sysid;
307 			bf.l_pid = sbf.l_pid;
308 		}
309 #if defined(_SYSCALL32_IMPL)
310 		else {
311 			struct flock32 sbf32;
312 			if (copyin((void *)arg, &sbf32, sizeof (sbf32))) {
313 				error = EFAULT;
314 				break;
315 			}
316 			bf.l_type = sbf32.l_type;
317 			bf.l_whence = sbf32.l_whence;
318 			bf.l_start = (off64_t)sbf32.l_start;
319 			bf.l_len = (off64_t)sbf32.l_len;
320 			bf.l_sysid = sbf32.l_sysid;
321 			bf.l_pid = sbf32.l_pid;
322 		}
323 #endif /* _SYSCALL32_IMPL */
324 
325 		/*
326 		 * 64-bit support: check for overflow for 32-bit lock ops
327 		 */
328 		if ((error = flock_check(vp, &bf, offset, maxoffset)) != 0)
329 			break;
330 
331 		/*
332 		 * Not all of the filesystems understand F_O_GETLK, and
333 		 * there's no need for them to know.  Map it to F_GETLK.
334 		 */
335 		if ((error = VOP_FRLOCK(vp, (cmd == F_O_GETLK) ? F_GETLK : cmd,
336 		    &bf, flag, offset, NULL, fp->f_cred, NULL)) != 0)
337 			break;
338 
339 		/*
340 		 * If command is GETLK and no lock is found, only
341 		 * the type field is changed.
342 		 */
343 		if ((cmd == F_O_GETLK || cmd == F_GETLK) &&
344 		    bf.l_type == F_UNLCK) {
345 			/* l_type always first entry, always a short */
346 			if (copyout(&bf.l_type, &((struct flock *)arg)->l_type,
347 			    sizeof (bf.l_type)))
348 				error = EFAULT;
349 			break;
350 		}
351 
352 		if (cmd == F_O_GETLK) {
353 			/*
354 			 * Return an SVR3 flock structure to the user.
355 			 */
356 			obf.l_type = (int16_t)bf.l_type;
357 			obf.l_whence = (int16_t)bf.l_whence;
358 			obf.l_start = (int32_t)bf.l_start;
359 			obf.l_len = (int32_t)bf.l_len;
360 			if (bf.l_sysid > SHRT_MAX || bf.l_pid > SHRT_MAX) {
361 				/*
362 				 * One or both values for the above fields
363 				 * is too large to store in an SVR3 flock
364 				 * structure.
365 				 */
366 				error = EOVERFLOW;
367 				break;
368 			}
369 			obf.l_sysid = (int16_t)bf.l_sysid;
370 			obf.l_pid = (int16_t)bf.l_pid;
371 			if (copyout(&obf, (void *)arg, sizeof (obf)))
372 				error = EFAULT;
373 		} else if (cmd == F_GETLK) {
374 			/*
375 			 * Copy out SVR4 flock.
376 			 */
377 			int i;
378 
379 			if (bf.l_start > maxoffset || bf.l_len > maxoffset) {
380 				error = EOVERFLOW;
381 				break;
382 			}
383 
384 			if (datamodel == DATAMODEL_NATIVE) {
385 				for (i = 0; i < 4; i++)
386 					sbf.l_pad[i] = 0;
387 				/*
388 				 * XXX	In an LP64 kernel with an LP64
389 				 *	application there's no need to do a
390 				 *	structure copy here as currently
391 				 *	struct flock == struct flock64.
392 				 *	We did it this way to avoid more
393 				 *	conditional compilation.
394 				 */
395 				sbf.l_type = bf.l_type;
396 				sbf.l_whence = bf.l_whence;
397 				sbf.l_start = (off_t)bf.l_start;
398 				sbf.l_len = (off_t)bf.l_len;
399 				sbf.l_sysid = bf.l_sysid;
400 				sbf.l_pid = bf.l_pid;
401 				if (copyout(&sbf, (void *)arg, sizeof (sbf)))
402 					error = EFAULT;
403 			}
404 #if defined(_SYSCALL32_IMPL)
405 			else {
406 				struct flock32 sbf32;
407 				if (bf.l_start > MAXOFF32_T ||
408 				    bf.l_len > MAXOFF32_T) {
409 					error = EOVERFLOW;
410 					break;
411 				}
412 				for (i = 0; i < 4; i++)
413 					sbf32.l_pad[i] = 0;
414 				sbf32.l_type = (int16_t)bf.l_type;
415 				sbf32.l_whence = (int16_t)bf.l_whence;
416 				sbf32.l_start = (off32_t)bf.l_start;
417 				sbf32.l_len = (off32_t)bf.l_len;
418 				sbf32.l_sysid = (int32_t)bf.l_sysid;
419 				sbf32.l_pid = (pid32_t)bf.l_pid;
420 				if (copyout(&sbf32,
421 				    (void *)arg, sizeof (sbf32)))
422 					error = EFAULT;
423 			}
424 #endif
425 		}
426 		break;
427 /* ONC_PLUS EXTRACT END */
428 
429 	case F_CHKFL:
430 		/*
431 		 * This is for internal use only, to allow the vnode layer
432 		 * to validate a flags setting before applying it.  User
433 		 * programs can't issue it.
434 		 */
435 		error = EINVAL;
436 		break;
437 
438 	case F_ALLOCSP:
439 	case F_FREESP:
440 	case F_ALLOCSP64:
441 	case F_FREESP64:
442 		/*
443 		 * Test for not-a-regular-file (and returning EINVAL)
444 		 * before testing for open-for-writing (and returning EBADF).
445 		 * This is relied upon by posix_fallocate() in libc.
446 		 */
447 		if (vp->v_type != VREG) {
448 			error = EINVAL;
449 			break;
450 		}
451 
452 		if ((flag & FWRITE) == 0) {
453 			error = EBADF;
454 			break;
455 		}
456 
457 		if (datamodel != DATAMODEL_ILP32 &&
458 		    (cmd == F_ALLOCSP64 || cmd == F_FREESP64)) {
459 			error = EINVAL;
460 			break;
461 		}
462 
463 #if defined(_ILP32) || defined(_SYSCALL32_IMPL)
464 		if (datamodel == DATAMODEL_ILP32 &&
465 		    (cmd == F_ALLOCSP || cmd == F_FREESP)) {
466 			struct flock32 sbf32;
467 			/*
468 			 * For compatibility we overlay an SVR3 flock on an SVR4
469 			 * flock.  This works because the input field offsets
470 			 * in "struct flock" were preserved.
471 			 */
472 			if (copyin((void *)arg, &sbf32, sizeof (sbf32))) {
473 				error = EFAULT;
474 				break;
475 			} else {
476 				bf.l_type = sbf32.l_type;
477 				bf.l_whence = sbf32.l_whence;
478 				bf.l_start = (off64_t)sbf32.l_start;
479 				bf.l_len = (off64_t)sbf32.l_len;
480 				bf.l_sysid = sbf32.l_sysid;
481 				bf.l_pid = sbf32.l_pid;
482 			}
483 		}
484 #endif /* _ILP32 || _SYSCALL32_IMPL */
485 
486 #if defined(_LP64)
487 		if (datamodel == DATAMODEL_LP64 &&
488 		    (cmd == F_ALLOCSP || cmd == F_FREESP)) {
489 			if (copyin((void *)arg, &bf, sizeof (bf))) {
490 				error = EFAULT;
491 				break;
492 			}
493 		}
494 #endif /* defined(_LP64) */
495 
496 #if !defined(_LP64) || defined(_SYSCALL32_IMPL)
497 		if (datamodel == DATAMODEL_ILP32 &&
498 		    (cmd == F_ALLOCSP64 || cmd == F_FREESP64)) {
499 			if (copyin((void *)arg, &bf64_32, sizeof (bf64_32))) {
500 				error = EFAULT;
501 				break;
502 			} else {
503 				/*
504 				 * Note that the size of flock64 is different in
505 				 * the ILP32 and LP64 models, due to the l_pad
506 				 * field. We do not want to assume that the
507 				 * flock64 structure is laid out the same in
508 				 * ILP32 and LP64 environments, so we will
509 				 * copy in the ILP32 version of flock64
510 				 * explicitly and copy it to the native
511 				 * flock64 structure.
512 				 */
513 				bf.l_type = (short)bf64_32.l_type;
514 				bf.l_whence = (short)bf64_32.l_whence;
515 				bf.l_start = bf64_32.l_start;
516 				bf.l_len = bf64_32.l_len;
517 				bf.l_sysid = (int)bf64_32.l_sysid;
518 				bf.l_pid = (pid_t)bf64_32.l_pid;
519 			}
520 		}
521 #endif /* !defined(_LP64) || defined(_SYSCALL32_IMPL) */
522 
523 		if (cmd == F_ALLOCSP || cmd == F_FREESP)
524 			error = flock_check(vp, &bf, offset, maxoffset);
525 		else if (cmd == F_ALLOCSP64 || cmd == F_FREESP64)
526 			error = flock_check(vp, &bf, offset, MAXOFFSET_T);
527 		if (error)
528 			break;
529 
530 		if (vp->v_type == VREG && bf.l_len == 0 &&
531 		    bf.l_start > OFFSET_MAX(fp)) {
532 			error = EFBIG;
533 			break;
534 		}
535 
536 		/*
537 		 * Make sure that there are no conflicting non-blocking
538 		 * mandatory locks in the region being manipulated. If
539 		 * there are such locks then return EACCES.
540 		 */
541 		if ((error = flock_get_start(vp, &bf, offset, &start)) != 0)
542 			break;
543 
544 		if (nbl_need_check(vp)) {
545 			u_offset_t	begin;
546 			ssize_t		length;
547 
548 			nbl_start_crit(vp, RW_READER);
549 			in_crit = 1;
550 			vattr.va_mask = AT_SIZE;
551 			if ((error = VOP_GETATTR(vp, &vattr, 0, CRED(), NULL))
552 			    != 0)
553 				break;
554 			begin = start > vattr.va_size ? vattr.va_size : start;
555 			length = vattr.va_size > start ? vattr.va_size - start :
556 			    start - vattr.va_size;
557 			if (nbl_conflict(vp, NBL_WRITE, begin, length, 0,
558 			    NULL)) {
559 				error = EACCES;
560 				break;
561 			}
562 		}
563 
564 		if (cmd == F_ALLOCSP64)
565 			cmd = F_ALLOCSP;
566 		else if (cmd == F_FREESP64)
567 			cmd = F_FREESP;
568 
569 		error = VOP_SPACE(vp, cmd, &bf, flag, offset, fp->f_cred, NULL);
570 
571 		break;
572 
573 #if !defined(_LP64) || defined(_SYSCALL32_IMPL)
574 /* ONC_PLUS EXTRACT START */
575 	case F_GETLK64:
576 	case F_SETLK64:
577 	case F_SETLKW64:
578 	case F_SETLK64_NBMAND:
579 		/*
580 		 * Large Files: Here we set cmd as *LK and send it to
581 		 * lower layers. *LK64 is only for the user land.
582 		 * Most of the comments described above for F_SETLK
583 		 * applies here too.
584 		 * Large File support is only needed for ILP32 apps!
585 		 */
586 		if (datamodel != DATAMODEL_ILP32) {
587 			error = EINVAL;
588 			break;
589 		}
590 
591 		if (cmd == F_GETLK64)
592 			cmd = F_GETLK;
593 		else if (cmd == F_SETLK64)
594 			cmd = F_SETLK;
595 		else if (cmd == F_SETLKW64)
596 			cmd = F_SETLKW;
597 		else if (cmd == F_SETLK64_NBMAND)
598 			cmd = F_SETLK_NBMAND;
599 
600 		/*
601 		 * Note that the size of flock64 is different in the ILP32
602 		 * and LP64 models, due to the sucking l_pad field.
603 		 * We do not want to assume that the flock64 structure is
604 		 * laid out in the same in ILP32 and LP64 environments, so
605 		 * we will copy in the ILP32 version of flock64 explicitly
606 		 * and copy it to the native flock64 structure.
607 		 */
608 
609 		if (copyin((void *)arg, &bf64_32, sizeof (bf64_32))) {
610 			error = EFAULT;
611 			break;
612 		}
613 
614 		bf.l_type = (short)bf64_32.l_type;
615 		bf.l_whence = (short)bf64_32.l_whence;
616 		bf.l_start = bf64_32.l_start;
617 		bf.l_len = bf64_32.l_len;
618 		bf.l_sysid = (int)bf64_32.l_sysid;
619 		bf.l_pid = (pid_t)bf64_32.l_pid;
620 
621 		if ((error = flock_check(vp, &bf, offset, MAXOFFSET_T)) != 0)
622 			break;
623 
624 		if ((error = VOP_FRLOCK(vp, cmd, &bf, flag, offset,
625 		    NULL, fp->f_cred, NULL)) != 0)
626 			break;
627 
628 		if ((cmd == F_GETLK) && bf.l_type == F_UNLCK) {
629 			if (copyout(&bf.l_type, &((struct flock *)arg)->l_type,
630 			    sizeof (bf.l_type)))
631 				error = EFAULT;
632 			break;
633 		}
634 
635 		if (cmd == F_GETLK) {
636 			int i;
637 
638 			/*
639 			 * We do not want to assume that the flock64 structure
640 			 * is laid out in the same in ILP32 and LP64
641 			 * environments, so we will copy out the ILP32 version
642 			 * of flock64 explicitly after copying the native
643 			 * flock64 structure to it.
644 			 */
645 			for (i = 0; i < 4; i++)
646 				bf64_32.l_pad[i] = 0;
647 			bf64_32.l_type = (int16_t)bf.l_type;
648 			bf64_32.l_whence = (int16_t)bf.l_whence;
649 			bf64_32.l_start = bf.l_start;
650 			bf64_32.l_len = bf.l_len;
651 			bf64_32.l_sysid = (int32_t)bf.l_sysid;
652 			bf64_32.l_pid = (pid32_t)bf.l_pid;
653 			if (copyout(&bf64_32, (void *)arg, sizeof (bf64_32)))
654 				error = EFAULT;
655 		}
656 		break;
657 /* ONC_PLUS EXTRACT END */
658 #endif /* !defined(_LP64) || defined(_SYSCALL32_IMPL) */
659 
660 /* ONC_PLUS EXTRACT START */
661 	case F_SHARE:
662 	case F_SHARE_NBMAND:
663 	case F_UNSHARE:
664 
665 		/*
666 		 * Copy in input fields only.
667 		 */
668 		if (copyin((void *)arg, &fsh, sizeof (fsh))) {
669 			error = EFAULT;
670 			break;
671 		}
672 
673 		/*
674 		 * Local share reservations always have this simple form
675 		 */
676 		shr.s_access = fsh.f_access;
677 		shr.s_deny = fsh.f_deny;
678 		shr.s_sysid = 0;
679 		shr.s_pid = ttoproc(curthread)->p_pid;
680 		shr_own.sl_pid = shr.s_pid;
681 		shr_own.sl_id = fsh.f_id;
682 		shr.s_own_len = sizeof (shr_own);
683 		shr.s_owner = (caddr_t)&shr_own;
684 		error = VOP_SHRLOCK(vp, cmd, &shr, flag, fp->f_cred, NULL);
685 /* ONC_PLUS EXTRACT END */
686 		break;
687 
688 	default:
689 		error = EINVAL;
690 		break;
691 	}
692 
693 	if (in_crit)
694 		nbl_end_crit(vp);
695 
696 done:
697 	releasef(fdes);
698 out:
699 	if (error)
700 		return (set_errno(error));
701 	return (retval);
702 }
703 
704 /* ONC_PLUS EXTRACT START */
705 int
706 flock_check(vnode_t *vp, flock64_t *flp, offset_t offset, offset_t max)
707 {
708 	struct vattr	vattr;
709 	int	error;
710 	u_offset_t start, end;
711 
712 	/*
713 	 * Determine the starting point of the request
714 	 */
715 	switch (flp->l_whence) {
716 	case 0:		/* SEEK_SET */
717 		start = (u_offset_t)flp->l_start;
718 		if (start > max)
719 			return (EINVAL);
720 		break;
721 	case 1:		/* SEEK_CUR */
722 		if (flp->l_start > (max - offset))
723 			return (EOVERFLOW);
724 		start = (u_offset_t)(flp->l_start + offset);
725 		if (start > max)
726 			return (EINVAL);
727 		break;
728 	case 2:		/* SEEK_END */
729 		vattr.va_mask = AT_SIZE;
730 		if (error = VOP_GETATTR(vp, &vattr, 0, CRED(), NULL))
731 			return (error);
732 		if (flp->l_start > (max - (offset_t)vattr.va_size))
733 			return (EOVERFLOW);
734 		start = (u_offset_t)(flp->l_start + (offset_t)vattr.va_size);
735 		if (start > max)
736 			return (EINVAL);
737 		break;
738 	default:
739 		return (EINVAL);
740 	}
741 
742 	/*
743 	 * Determine the range covered by the request.
744 	 */
745 	if (flp->l_len == 0)
746 		end = MAXEND;
747 	else if ((offset_t)flp->l_len > 0) {
748 		if (flp->l_len > (max - start + 1))
749 			return (EOVERFLOW);
750 		end = (u_offset_t)(start + (flp->l_len - 1));
751 		ASSERT(end <= max);
752 	} else {
753 		/*
754 		 * Negative length; why do we even allow this ?
755 		 * Because this allows easy specification of
756 		 * the last n bytes of the file.
757 		 */
758 		end = start;
759 		start += (u_offset_t)flp->l_len;
760 		(start)++;
761 		if (start > max)
762 			return (EINVAL);
763 		ASSERT(end <= max);
764 	}
765 	ASSERT(start <= max);
766 	if (flp->l_type == F_UNLCK && flp->l_len > 0 &&
767 	    end == (offset_t)max) {
768 		flp->l_len = 0;
769 	}
770 	if (start  > end)
771 		return (EINVAL);
772 	return (0);
773 }
774 
775 static int
776 flock_get_start(vnode_t *vp, flock64_t *flp, offset_t offset, u_offset_t *start)
777 {
778 	struct vattr	vattr;
779 	int	error;
780 
781 	/*
782 	 * Determine the starting point of the request. Assume that it is
783 	 * a valid starting point.
784 	 */
785 	switch (flp->l_whence) {
786 	case 0:		/* SEEK_SET */
787 		*start = (u_offset_t)flp->l_start;
788 		break;
789 	case 1:		/* SEEK_CUR */
790 		*start = (u_offset_t)(flp->l_start + offset);
791 		break;
792 	case 2:		/* SEEK_END */
793 		vattr.va_mask = AT_SIZE;
794 		if (error = VOP_GETATTR(vp, &vattr, 0, CRED(), NULL))
795 			return (error);
796 		*start = (u_offset_t)(flp->l_start + (offset_t)vattr.va_size);
797 		break;
798 	default:
799 		return (EINVAL);
800 	}
801 
802 	return (0);
803 }
804 
805 /*
806  * Take rctl action when the requested file descriptor is too big.
807  */
808 static void
809 fd_too_big(proc_t *p)
810 {
811 	mutex_enter(&p->p_lock);
812 	(void) rctl_action(rctlproc_legacy[RLIMIT_NOFILE],
813 	    p->p_rctls, p, RCA_SAFE);
814 	mutex_exit(&p->p_lock);
815 }
816 /* ONC_PLUS EXTRACT END */
817