xref: /netbsd-src/sys/compat/linux32/common/linux32_unistd.c (revision eb961d0e02b7a46a9acfa877b02df48df6637278)
1 /*	$NetBSD: linux32_unistd.c,v 1.1 2006/02/09 19:18:57 manu Exp $ */
2 
3 /*-
4  * Copyright (c) 2006 Emmanuel Dreyfus, all rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Emmanuel Dreyfus
17  * 4. The name of the author may not be used to endorse or promote
18  *    products derived from this software without specific prior written
19  *    permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS''
22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 
36 __KERNEL_RCSID(0, "$NetBSD: linux32_unistd.c,v 1.1 2006/02/09 19:18:57 manu Exp $");
37 
38 #include <sys/types.h>
39 #include <sys/param.h>
40 #include <sys/fstypes.h>
41 #include <sys/signal.h>
42 #include <sys/dirent.h>
43 #include <sys/kernel.h>
44 #include <sys/fcntl.h>
45 #include <sys/select.h>
46 #include <sys/sa.h>
47 #include <sys/proc.h>
48 #include <sys/ucred.h>
49 #include <sys/swap.h>
50 
51 #include <machine/types.h>
52 
53 #include <sys/syscallargs.h>
54 
55 #include <compat/netbsd32/netbsd32.h>
56 #include <compat/netbsd32/netbsd32_conv.h>
57 #include <compat/netbsd32/netbsd32_syscallargs.h>
58 
59 #include <compat/linux/common/linux_types.h>
60 #include <compat/linux/common/linux_signal.h>
61 #include <compat/linux/common/linux_machdep.h>
62 #include <compat/linux/common/linux_misc.h>
63 #include <compat/linux/common/linux_oldolduname.h>
64 #include <compat/linux/linux_syscallargs.h>
65 
66 #include <compat/linux32/common/linux32_types.h>
67 #include <compat/linux32/common/linux32_signal.h>
68 #include <compat/linux32/common/linux32_machdep.h>
69 #include <compat/linux32/common/linux32_sysctl.h>
70 #include <compat/linux32/common/linux32_socketcall.h>
71 #include <compat/linux32/linux32_syscallargs.h>
72 
73 static int linux32_select1(struct lwp *, register_t *,
74     int, fd_set *, fd_set *, fd_set *, struct timeval *);
75 
76 int
77 linux32_sys_brk(l, v, retval)
78 	struct lwp *l;
79 	void *v;
80 	register_t *retval;
81 {
82 	struct linux32_sys_brk_args /* {
83 		syscallarg(netbsd32_charp) nsize;
84 	} */ *uap = v;
85 	struct linux_sys_brk_args ua;
86 
87 	NETBSD32TOP_UAP(nsize, char);
88 	return linux_sys_brk(l, &ua, retval);
89 }
90 
91 int
92 linux32_sys_access(l, v, retval)
93 	struct lwp *l;
94 	void *v;
95 	register_t *retval;
96 {
97 	struct linux32_sys_access_args /* {
98 		syscallarg(const netbsd32_charp) path;
99 		syscallarg(int) flags;
100 	} */ *uap = v;
101 	struct sys_access_args ua;
102 	caddr_t sg;
103 
104 	NETBSD32TOP_UAP(path, const char);
105 	NETBSD32TO64_UAP(flags);
106 
107 	sg = stackgap_init(l->l_proc, 0);
108 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
109 
110 	return sys_access(l, &ua, retval);
111 }
112 
113 int
114 linux32_sys_llseek(l, v, retval)
115 	struct lwp *l;
116 	void *v;
117 	register_t *retval;
118 {
119 	struct linux32_sys_llseek_args /* {
120 		syscallcarg(int) fd;
121                 syscallarg(u_int32_t) ohigh;
122                 syscallarg(u_int32_t) olow;
123 		syscallarg(netbsd32_caddr_t) res;
124 		syscallcarg(int) whence;
125 	} */ *uap = v;
126 	struct linux_sys_llseek_args ua;
127 
128 	NETBSD32TO64_UAP(fd);
129 	NETBSD32TO64_UAP(ohigh);
130 	NETBSD32TO64_UAP(olow);
131 	NETBSD32TOP_UAP(res, char);
132 	NETBSD32TO64_UAP(whence);
133 
134 	return linux_sys_llseek(l, &ua, retval);
135 }
136 
137 int
138 linux32_sys_readlink(l, v, retval)
139 	struct lwp *l;
140 	void *v;
141 	register_t *retval;
142 {
143 	struct linux32_sys_readlink_args /* {
144 		syscallarg(const netbsd32_charp) name;
145 		syscallarg(netbsd32_charp) buf;
146 		syscallarg(int) count;
147 	} */ *uap = v;
148 	struct linux_sys_readlink_args ua;
149 
150 	NETBSD32TOP_UAP(name, const char);
151 	NETBSD32TOP_UAP(buf, char)
152 	NETBSD32TO64_UAP(count);
153 
154 	return linux_sys_readlink(l, &ua, retval);
155 }
156 
157 
158 int
159 linux32_sys_select(l, v, retval)
160 	struct lwp *l;
161 	void *v;
162 	register_t *retval;
163 {
164 	struct linux32_sys_select_args /* {
165 		syscallarg(int) nfds;
166 		syscallarg(netbsd32_fd_setp_t) readfds;
167 		syscallarg(netbsd32_fd_setp_t) writefds;
168 		syscallarg(netbsd32_fd_setp_t) exceptfds;
169 		syscallarg(netbsd32_timevalp_t) timeout;
170 	} */ *uap = v;
171 
172 	return linux32_select1(l, retval, SCARG(uap, nfds),
173 	    NETBSD32PTR64(SCARG(uap, readfds)),
174 	    NETBSD32PTR64(SCARG(uap, writefds)),
175 	    NETBSD32PTR64(SCARG(uap, exceptfds)),
176 	    NETBSD32PTR64(SCARG(uap, timeout)));
177 }
178 
179 int
180 linux32_sys_oldselect(l, v, retval)
181 	struct lwp *l;
182 	void *v;
183 	register_t *retval;
184 {
185 	struct linux32_sys_oldselect_args /* {
186 		syscallarg(linux32_oldselectp_t) lsp;
187 	} */ *uap = v;
188 	struct linux32_oldselect lsp32;
189 	int error;
190 
191 	if ((error = copyin(NETBSD32PTR64(SCARG(uap, lsp)),
192 	    &lsp32, sizeof(lsp32))) != 0)
193 		return error;
194 
195 	return linux32_select1(l, retval, lsp32.nfds,
196 	     NETBSD32PTR64(lsp32.readfds), NETBSD32PTR64(lsp32.writefds),
197 	     NETBSD32PTR64(lsp32.exceptfds), NETBSD32PTR64(lsp32.timeout));
198 }
199 
200 static int
201 linux32_select1(l, retval, nfds, readfds, writefds, exceptfds, timeout)
202         struct lwp *l;
203         register_t *retval;
204         int nfds;
205         fd_set *readfds, *writefds, *exceptfds;
206         struct timeval *timeout;
207 {
208 	struct timeval tv0, tv1, utv, otv;
209 	struct netbsd32_timeval utv32;
210 	int error;
211 
212 	/*
213 	 * Store current time for computation of the amount of
214 	 * time left.
215 	 */
216 	if (timeout) {
217 		if ((error = copyin(timeout, &utv32, sizeof(utv32))))
218 			return error;
219 
220 		netbsd32_to_timeval(&utv32, &utv);
221 		otv = utv;
222 
223 		if (itimerfix(&utv)) {
224 			/*
225 			 * The timeval was invalid.  Convert it to something
226 			 * valid that will act as it does under Linux.
227 			 */
228 			utv.tv_sec += utv.tv_usec / 1000000;
229 			utv.tv_usec %= 1000000;
230 			if (utv.tv_usec < 0) {
231 				utv.tv_sec -= 1;
232 				utv.tv_usec += 1000000;
233 			}
234 			if (utv.tv_sec < 0)
235 				timerclear(&utv);
236 		}
237 		microtime(&tv0);
238 	} else {
239 		timerclear(&utv);
240 	}
241 
242 	error = selcommon(l, retval, nfds,
243 	    readfds, writefds, exceptfds, &utv, NULL);
244 
245 	if (error) {
246 		/*
247 		 * See fs/select.c in the Linux kernel.  Without this,
248 		 * Maelstrom doesn't work.
249 		 */
250 		if (error == ERESTART)
251 			error = EINTR;
252 		return error;
253 	}
254 
255 	if (timeout) {
256 		if (*retval) {
257 			/*
258 			 * Compute how much time was left of the timeout,
259 			 * by subtracting the current time and the time
260 			 * before we started the call, and subtracting
261 			 * that result from the user-supplied value.
262 			 */
263 			microtime(&tv1);
264 			timersub(&tv1, &tv0, &tv1);
265 			timersub(&otv, &tv1, &utv);
266 			if (utv.tv_sec < 0)
267 				timerclear(&utv);
268 		} else {
269 			timerclear(&utv);
270 		}
271 
272 		netbsd32_from_timeval(&utv, &utv32);
273 
274 		if ((error = copyout(&utv32, timeout, sizeof(utv32))))
275 			return error;
276 	}
277 
278 	return 0;
279 }
280 
281 int
282 linux32_sys_pipe(l, v, retval)
283 	struct lwp *l;
284 	void *v;
285 	register_t *retval;
286 {
287 	struct linux32_sys_pipe_args /* {
288 		syscallarg(netbsd32_intp) fd;
289 	} */ *uap = v;
290 	int error;
291 	int pfds[2];
292 
293 	if ((error = sys_pipe(l, 0, retval)))
294 		return error;
295 
296 	pfds[0] = (int)retval[0];
297 	pfds[1] = (int)retval[1];
298 
299 	if ((error = copyout(pfds, NETBSD32PTR64(SCARG(uap, fd)),
300 	    2 * sizeof (int))) != 0)
301 		return error;
302 
303 	retval[0] = 0;
304 	retval[1] = 0;
305 
306 	return 0;
307 }
308 
309 
310 int
311 linux32_sys_unlink(l, v, retval)
312 	struct lwp *l;
313 	void *v;
314 	register_t *retval;
315 {
316 	struct linux32_sys_unlink_args /* {
317 		syscallarg(const netbsd32_charp) path;
318 	} */ *uap = v;
319 	struct linux_sys_unlink_args ua;
320 
321 	NETBSD32TOP_UAP(path, const char);
322 
323 	return linux_sys_unlink(l, &ua, retval);
324 }
325 
326 int
327 linux32_sys_chdir(l, v, retval)
328 	struct lwp *l;
329 	void *v;
330 	register_t *retval;
331 {
332 	struct linux32_sys_chdir_args /* {
333 		syscallarg(const netbsd32_charp) path;
334 	} */ *uap = v;
335 	struct sys_chdir_args ua;
336 	caddr_t sg = stackgap_init(l->l_proc, 0);
337 
338 	NETBSD32TOP_UAP(path, const char);
339 
340 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
341 
342 	return sys_chdir(l, &ua, retval);
343 }
344 
345 int
346 linux32_sys_link(l, v, retval)
347 	struct lwp *l;
348 	void *v;
349 	register_t *retval;
350 {
351 	struct linux32_sys_link_args /* {
352 		syscallarg(const netbsd32_charp) path;
353 		syscallarg(const netbsd32_charp) link;
354 	} */ *uap = v;
355 	struct sys_link_args ua;
356 	caddr_t sg = stackgap_init(l->l_proc, 0);
357 
358 	NETBSD32TOP_UAP(path, const char);
359 	NETBSD32TOP_UAP(link, const char);
360 
361 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
362 	CHECK_ALT_CREAT(l, &sg, SCARG(&ua, link));
363 
364 	return sys_link(l, &ua, retval);
365 }
366 
367 int
368 linux32_sys_creat(l, v, retval)
369 	struct lwp *l;
370 	void *v;
371 	register_t *retval;
372 {
373 	struct linux32_sys_creat_args /* {
374 		syscallarg(const netbsd32_charp) path;
375 		syscallarg(int) mode;
376 	} */ *uap = v;
377 	struct sys_open_args ua;
378 	caddr_t sg = stackgap_init(l->l_proc, 0);
379 
380 	NETBSD32TOP_UAP(path, const char);
381 	SCARG(&ua, flags) = O_CREAT | O_TRUNC | O_WRONLY;
382 	NETBSD32TO64_UAP(mode);
383 
384 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
385 
386 	return sys_open(l, &ua, retval);
387 }
388 
389 int
390 linux32_sys_mknod(l, v, retval)
391 	struct lwp *l;
392 	void *v;
393 	register_t *retval;
394 {
395 	struct linux32_sys_mknod_args /* {
396 		syscallarg(const netbsd32_charp) path;
397 		syscallarg(int) mode;
398 		syscallarg(int) dev;
399 	} */ *uap = v;
400 	struct linux_sys_mknod_args ua;
401 
402 	NETBSD32TOP_UAP(path, const char);
403 	NETBSD32TO64_UAP(mode);
404 	NETBSD32TO64_UAP(dev);
405 
406 	return linux_sys_mknod(l, &ua, retval);
407 }
408 
409 int
410 linux32_sys_chmod(l, v, retval)
411 	struct lwp *l;
412 	void *v;
413 	register_t *retval;
414 {
415 	struct linux32_sys_chmod_args /* {
416 		syscallarg(const netbsd32_charp) path;
417 		syscallarg(int) mode;
418 	} */ *uap = v;
419 	struct sys_chmod_args ua;
420 	caddr_t sg = stackgap_init(l->l_proc, 0);
421 
422 	NETBSD32TOP_UAP(path, const char);
423 	NETBSD32TO64_UAP(mode);
424 
425 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
426 
427 	return sys_chmod(l, &ua, retval);
428 }
429 
430 int
431 linux32_sys_lchown16(l, v, retval)
432 	struct lwp *l;
433 	void *v;
434 	register_t *retval;
435 {
436 	struct linux32_sys_lchown16_args /* {
437 		syscallarg(const netbsd32_charp) path;
438 		syscallarg(int) uid;
439 		syscallarg(int) gid;
440 	} */ *uap = v;
441         struct sys___posix_lchown_args ua;
442         caddr_t sg = stackgap_init(l->l_proc, 0);
443 
444 	NETBSD32TOP_UAP(path, const char);
445         CHECK_ALT_SYMLINK(l, &sg, SCARG(&ua, path));
446 
447         if ((linux32_uid_t)SCARG(uap, uid) == (linux32_uid_t)-1)
448         	SCARG(&ua, uid) = (uid_t)-1;
449 	else
450         	SCARG(&ua, uid) = SCARG(uap, uid);
451 
452         if ((linux32_gid_t)SCARG(uap, gid) == (linux32_gid_t)-1)
453         	SCARG(&ua, gid) = (gid_t)-1;
454 	else
455         	SCARG(&ua, gid) = SCARG(uap, gid);
456 
457         return sys___posix_lchown(l, &ua, retval);
458 }
459 
460 int
461 linux32_sys_break(l, v, retval)
462 	struct lwp *l;
463 	void *v;
464 	register_t *retval;
465 {
466 #if 0
467 	struct linux32_sys_break_args /* {
468 		syscallarg(const netbsd32_charp) nsize;
469 	} */ *uap = v;
470 #endif
471 
472 	return ENOSYS;
473 }
474 
475 int
476 linux32_sys_rename(l, v, retval)
477 	struct lwp *l;
478 	void *v;
479 	register_t *retval;
480 {
481 	struct linux32_sys_rename_args /* {
482 		syscallarg(const netbsd32_charp) from;
483 		syscallarg(const netbsd32_charp) to;
484 	} */ *uap = v;
485 	struct sys_rename_args ua;
486 	caddr_t sg = stackgap_init(l->l_proc, 0);
487 
488 	NETBSD32TOP_UAP(from, const char);
489 	NETBSD32TOP_UAP(to, const char);
490 
491 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, from));
492 	CHECK_ALT_CREAT(l, &sg, SCARG(&ua, to));
493 
494 	return sys___posix_rename(l, &ua, retval);
495 }
496 
497 int
498 linux32_sys_mkdir(l, v, retval)
499 	struct lwp *l;
500 	void *v;
501 	register_t *retval;
502 {
503 	struct linux32_sys_mkdir_args /* {
504 		syscallarg(const netbsd32_charp) path;
505 		syscallarg(int) mode;
506 	} */ *uap = v;
507 	struct sys_mkdir_args ua;
508 	caddr_t sg = stackgap_init(l->l_proc, 0);
509 
510 	NETBSD32TOP_UAP(path, const char);
511 	NETBSD32TO64_UAP(mode);
512 
513 	CHECK_ALT_CREAT(l, &sg, SCARG(&ua, path));
514 
515 	return sys_mkdir(l, &ua, retval);
516 }
517 
518 int
519 linux32_sys_rmdir(l, v, retval)
520 	struct lwp *l;
521 	void *v;
522 	register_t *retval;
523 {
524 	struct linux32_sys_rmdir_args /* {
525 		syscallarg(const netbsd32_charp) path;
526 	} */ *uap = v;
527 	struct sys_rmdir_args ua;
528 	caddr_t sg = stackgap_init(l->l_proc, 0);
529 
530 	NETBSD32TOP_UAP(path, const char);
531 
532 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
533 
534 	return sys_rmdir(l, &ua, retval);
535 }
536 
537 int
538 linux32_sys_getgroups16(l, v, retval)
539 	struct lwp *l;
540 	void *v;
541 	register_t *retval;
542 {
543 	struct linux32_sys_getgroups16_args /* {
544 		syscallarg(int) gidsetsize;
545 		syscallarg(linux32_gidp_t) gidset;
546 	} */ *uap = v;
547 	struct linux_sys_getgroups16_args ua;
548 
549 	NETBSD32TO64_UAP(gidsetsize);
550 	NETBSD32TOP_UAP(gidset, linux32_gid_t);
551 
552 	return linux_sys_getgroups16(l, &ua, retval);
553 }
554 
555 int
556 linux32_sys_setgroups16(l, v, retval)
557 	struct lwp *l;
558 	void *v;
559 	register_t *retval;
560 {
561 	struct linux32_sys_setgroups16_args /* {
562 		syscallarg(int) gidsetsize;
563 		syscallarg(linux32_gidp_t) gidset;
564 	} */ *uap = v;
565 	struct linux_sys_setgroups16_args ua;
566 
567 	NETBSD32TO64_UAP(gidsetsize);
568 	NETBSD32TOP_UAP(gidset, linux32_gid_t);
569 
570 	return linux_sys_setgroups16(l, &ua, retval);
571 }
572 
573 int
574 linux32_sys_symlink(l, v, retval)
575 	struct lwp *l;
576 	void *v;
577 	register_t *retval;
578 {
579 	struct linux32_sys_symlink_args /* {
580 		syscallarg(const netbsd32_charp) path;
581 		syscallarg(const netbsd32_charp) link;
582 	} */ *uap = v;
583 	struct sys_symlink_args ua;
584 	caddr_t sg = stackgap_init(l->l_proc, 0);
585 
586 	NETBSD32TOP_UAP(path, const char);
587 	NETBSD32TOP_UAP(link, const char);
588 
589 	CHECK_ALT_EXIST(l, &sg, SCARG(&ua, path));
590 	CHECK_ALT_CREAT(l, &sg, SCARG(&ua, link));
591 
592 	return sys_symlink(l, &ua, retval);
593 }
594 
595 
596 int
597 linux32_sys_swapon(l, v, retval)
598 	struct lwp *l;
599 	void *v;
600 	register_t *retval;
601 {
602 	struct linux32_sys_swapon_args /* {
603 		syscallarg(const netbsd32_charp) name;
604 	} */ *uap = v;
605 	struct sys_swapctl_args ua;
606 
607         SCARG(&ua, cmd) = SWAP_ON;
608         SCARG(&ua, arg) = (void *)__UNCONST(NETBSD32PTR64(SCARG(uap, name)));
609         SCARG(&ua, misc) = 0;   /* priority */
610         return (sys_swapctl(l, &ua, retval));
611 }
612 
613 int
614 linux32_sys_swapoff(l, v, retval)
615 	struct lwp *l;
616 	void *v;
617 	register_t *retval;
618 {
619 	struct linux32_sys_swapoff_args /* {
620 		syscallarg(const netbsd32_charp) path;
621 	} */ *uap = v;
622 	struct sys_swapctl_args ua;
623 
624         SCARG(&ua, cmd) = SWAP_OFF;
625         SCARG(&ua, arg) = (void *)__UNCONST(NETBSD32PTR64(SCARG(uap, path)));
626         SCARG(&ua, misc) = 0;   /* priority */
627         return (sys_swapctl(l, &ua, retval));
628 }
629 
630 
631 int
632 linux32_sys_reboot(l, v, retval)
633 	struct lwp *l;
634 	void *v;
635 	register_t *retval;
636 {
637 	struct linux32_sys_reboot_args /* {
638 		syscallarg(int) magic1;
639 		syscallarg(int) magic2;
640 		syscallarg(int) cmd;
641 		syscallarg(netbsd32_voidp) arg;
642 	} */ *uap = v;
643 	struct linux_sys_reboot_args ua;
644 
645 	NETBSD32TO64_UAP(magic1);
646 	NETBSD32TO64_UAP(magic2);
647 	NETBSD32TO64_UAP(cmd);
648 	NETBSD32TOP_UAP(arg, void);
649 
650 	return linux_sys_reboot(l, &ua, retval);
651 }
652 
653 int
654 linux32_sys_truncate(l, v, retval)
655 	struct lwp *l;
656 	void *v;
657 	register_t *retval;
658 {
659 	struct linux32_sys_truncate_args /* {
660 		syscallarg(const netbsd32_charp) path;
661 		syscallarg(netbsd32_charp) buf;
662 		syscallarg(int) count;
663 	} */ *uap = v;
664 	struct compat_43_sys_truncate_args ua;
665 
666 	NETBSD32TOP_UAP(path, const char);
667 	NETBSD32TO64_UAP(length);
668 
669 	return compat_43_sys_truncate(l, &ua, retval);
670 }
671 
672 int
673 linux32_sys_fchown16(l, v, retval)
674 	struct lwp *l;
675 	void *v;
676 	register_t *retval;
677 {
678 	struct linux32_sys_fchown16_args /* {
679 		syscallarg(int) fd;
680 		syscallarg(int) uid;
681 		syscallarg(int) gid;
682 	} */ *uap = v;
683         struct sys___posix_fchown_args ua;
684 
685 	SCARG(&ua, fd) = SCARG(uap, fd);
686 
687         if ((linux32_uid_t)SCARG(uap, uid) == (linux32_uid_t)-1)
688         	SCARG(&ua, uid) = (uid_t)-1;
689 	else
690         	SCARG(&ua, uid) = SCARG(uap, uid);
691 
692         if ((linux32_gid_t)SCARG(uap, gid) == (linux32_gid_t)-1)
693         	SCARG(&ua, gid) = (gid_t)-1;
694 	else
695         	SCARG(&ua, gid) = SCARG(uap, gid);
696 
697         return sys___posix_fchown(l, &ua, retval);
698 }
699