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 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #include <sys/param.h>
33 #include <sys/types.h>
34 #include <sys/sysmacros.h>
35 #include <sys/systm.h>
36 #include <sys/errno.h>
37 #include <sys/proc.h>
38 #include <sys/fault.h>
39 #include <sys/signal.h>
40 #include <sys/siginfo.h>
41 #include <sys/debug.h>
42 
43 int
44 sigaltstack(struct sigaltstack *ssp, struct sigaltstack *oss)
45 {
46 	klwp_t *lwp = ttolwp(curthread);
47 	struct sigaltstack ss;
48 
49 	/*
50 	 * User's oss and ss might be the same address, so copyin first and
51 	 * save before copying out.
52 	 */
53 	if (ssp) {
54 		if (lwp->lwp_sigaltstack.ss_flags & SS_ONSTACK)
55 			return (set_errno(EPERM));
56 		if (copyin(ssp, &ss, sizeof (ss)))
57 			return (set_errno(EFAULT));
58 		if (ss.ss_flags & ~SS_DISABLE)
59 			return (set_errno(EINVAL));
60 		if (!(ss.ss_flags & SS_DISABLE) && ss.ss_size < MINSIGSTKSZ)
61 			return (set_errno(ENOMEM));
62 	}
63 
64 	if (oss) {
65 		if (copyout(&lwp->lwp_sigaltstack,
66 		    oss, sizeof (struct sigaltstack)))
67 			return (set_errno(EFAULT));
68 	}
69 
70 	if (ssp)
71 		lwp->lwp_sigaltstack = ss;
72 
73 	return (0);
74 }
75 
76 #ifdef _LP64
77 int
78 sigaltstack32(struct sigaltstack32 *ssp, struct sigaltstack32 *oss)
79 {
80 	klwp_t *lwp = ttolwp(curthread);
81 	struct sigaltstack   *ss;
82 	struct sigaltstack32 ss32, oss32;
83 
84 	/*
85 	 * User's oss and ss might be the same address, so copyin first and
86 	 * save before copying out.
87 	 */
88 	if (ssp) {
89 		if (lwp->lwp_sigaltstack.ss_flags & SS_ONSTACK)
90 			return (set_errno(EPERM));
91 		if (copyin(ssp, &ss32, sizeof (ss32)))
92 			return (set_errno(EFAULT));
93 		if (ss32.ss_flags & ~SS_DISABLE)
94 			return (set_errno(EINVAL));
95 		if (!(ss32.ss_flags & SS_DISABLE) && ss32.ss_size < MINSIGSTKSZ)
96 			return (set_errno(ENOMEM));
97 	}
98 
99 	if (oss) {
100 		/*
101 		 * copy to ILP32 struct before copyout.
102 		 */
103 		ss = &lwp->lwp_sigaltstack;
104 		oss32.ss_sp    = (caddr32_t)(uintptr_t)ss->ss_sp;
105 		oss32.ss_size  = (size32_t)ss->ss_size;
106 		oss32.ss_flags = ss->ss_flags;
107 
108 		if (copyout(&oss32, oss, sizeof (oss32)))
109 			return (set_errno(EFAULT));
110 	}
111 
112 	if (ssp) {
113 		ss = &lwp->lwp_sigaltstack;
114 		ss->ss_sp = (void *)(uintptr_t)ss32.ss_sp;
115 		ss->ss_size = (size_t)ss32.ss_size;
116 		ss->ss_flags = ss32.ss_flags;
117 	}
118 
119 	return (0);
120 }
121 #endif /* _LP64 */
122