xref: /freebsd/sys/fs/procfs/procfs_regs.c (revision 0d66206fff44f864ea8a4b220c3a53b4caa959a0)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1993 Jan-Simon Pendry
5  * Copyright (c) 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Jan-Simon Pendry.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)procfs_regs.c	8.4 (Berkeley) 6/15/94
36  *
37  * From:
38  *	$Id: procfs_regs.c,v 3.2 1993/12/15 09:40:17 jsp Exp $
39  * $FreeBSD$
40  */
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/proc.h>
47 #include <sys/ptrace.h>
48 #include <sys/uio.h>
49 
50 #include <fs/pseudofs/pseudofs.h>
51 #include <fs/procfs/procfs.h>
52 
53 #ifdef COMPAT_FREEBSD32
54 #include <sys/procfs.h>
55 #include <sys/sysent.h>
56 #include <machine/fpu.h>
57 
58 /*
59  * PROC(write, regs, td2, &r) becomes
60  * proc_write_regs(td2, &r)   or
61  * proc_write_regs32(td2, &r32)
62  *
63  * UIOMOVE_FROMBUF(r, uio) becomes
64  * uiomove_frombuf(&r, sizeof(r), uio)  or
65  * uiomove_frombuf(&r32, sizeof(r32), uio)
66  */
67 #define	PROC(d, w, t, r)	wrap32 ? \
68 	proc_ ## d ## _ ## w ## 32(t, r ## 32) : \
69 	proc_ ## d ## _ ## w(t, r)
70 #define	UIOMOVE_FROMBUF(k, u)	wrap32 ? \
71 	uiomove_frombuf(& k ## 32, sizeof(k ## 32), u) : \
72 	uiomove_frombuf(& k, sizeof(k), u)
73 #else
74 #define	PROC(d, w, t, r)	proc_ ## d ## _ ## w(t, r)
75 #define	UIOMOVE_FROMBUF(k, u)	uiomove_frombuf(& k, sizeof(k), u)
76 #endif
77 
78 int
79 procfs_doprocregs(PFS_FILL_ARGS)
80 {
81 	int error;
82 	struct reg r;
83 	struct thread *td2;
84 #ifdef COMPAT_FREEBSD32
85 	struct reg32 r32;
86 	int wrap32 = 0;
87 #endif
88 
89 	if (uio->uio_offset != 0)
90 		return (0);
91 
92 	PROC_LOCK(p);
93 	PROC_ASSERT_HELD(p);
94 	if (p_candebug(td, p)) {
95 		PROC_UNLOCK(p);
96 		return (EPERM);
97 	}
98 	if (!P_SHOULDSTOP(p)) {
99 		PROC_UNLOCK(p);
100 		return (EBUSY);
101 	}
102 
103 	td2 = FIRST_THREAD_IN_PROC(p);
104 #ifdef COMPAT_FREEBSD32
105 	if (SV_CURPROC_FLAG(SV_ILP32)) {
106 		if ((SV_PROC_FLAG(td2->td_proc, SV_ILP32)) == 0) {
107 			PROC_UNLOCK(p);
108 			return (EINVAL);
109 		}
110 		wrap32 = 1;
111 		memset(&r32, 0, sizeof(r32));
112 	} else
113 #endif
114 		memset(&r, 0, sizeof(r));
115 	error = PROC(read, regs, td2, &r);
116 	if (error == 0) {
117 		PROC_UNLOCK(p);
118 		error = UIOMOVE_FROMBUF(r, uio);
119 		PROC_LOCK(p);
120 	}
121 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
122 		if (!P_SHOULDSTOP(p))
123 			error = EBUSY;
124 		else
125 			/* XXXKSE: */
126 			error = PROC(write, regs, td2, &r);
127 	}
128 	PROC_UNLOCK(p);
129 
130 	return (error);
131 }
132