xref: /freebsd/sys/fs/procfs/procfs_regs.c (revision f01edb6f5d55fe093f8ab9c5da2b1707af698a56)
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/sysent.h>
49 #include <sys/uio.h>
50 
51 #include <machine/reg.h>
52 
53 #include <fs/pseudofs/pseudofs.h>
54 #include <fs/procfs/procfs.h>
55 
56 #ifdef COMPAT_FREEBSD32
57 #include <sys/procfs.h>
58 #include <machine/fpu.h>
59 
60 /*
61  * PROC(write, regs, td2, &r) becomes
62  * proc_write_regs(td2, &r)   or
63  * proc_write_regs32(td2, &r32)
64  *
65  * UIOMOVE_FROMBUF(r, uio) becomes
66  * uiomove_frombuf(&r, sizeof(r), uio)  or
67  * uiomove_frombuf(&r32, sizeof(r32), uio)
68  */
69 #define	PROC(d, w, t, r)	wrap32 ? \
70 	proc_ ## d ## _ ## w ## 32(t, r ## 32) : \
71 	proc_ ## d ## _ ## w(t, r)
72 #define	UIOMOVE_FROMBUF(k, u)	wrap32 ? \
73 	uiomove_frombuf(& k ## 32, sizeof(k ## 32), u) : \
74 	uiomove_frombuf(& k, sizeof(k), u)
75 #else
76 #define	PROC(d, w, t, r)	proc_ ## d ## _ ## w(t, r)
77 #define	UIOMOVE_FROMBUF(k, u)	uiomove_frombuf(& k, sizeof(k), u)
78 #endif
79 
80 int
81 procfs_doprocregs(PFS_FILL_ARGS)
82 {
83 	int error;
84 	struct reg r;
85 	struct thread *td2;
86 #ifdef COMPAT_FREEBSD32
87 	struct reg32 r32;
88 	int wrap32 = 0;
89 #endif
90 
91 	if (uio->uio_offset != 0)
92 		return (0);
93 
94 	PROC_LOCK(p);
95 	PROC_ASSERT_HELD(p);
96 	if (p_candebug(td, p)) {
97 		PROC_UNLOCK(p);
98 		return (EPERM);
99 	}
100 	if (!P_SHOULDSTOP(p)) {
101 		PROC_UNLOCK(p);
102 		return (EBUSY);
103 	}
104 
105 	td2 = FIRST_THREAD_IN_PROC(p);
106 #ifdef COMPAT_FREEBSD32
107 	if (SV_CURPROC_FLAG(SV_ILP32)) {
108 		if ((SV_PROC_FLAG(td2->td_proc, SV_ILP32)) == 0) {
109 			PROC_UNLOCK(p);
110 			return (EINVAL);
111 		}
112 		wrap32 = 1;
113 		memset(&r32, 0, sizeof(r32));
114 	} else
115 #endif
116 		memset(&r, 0, sizeof(r));
117 	error = PROC(read, regs, td2, &r);
118 	if (error == 0) {
119 		PROC_UNLOCK(p);
120 		error = UIOMOVE_FROMBUF(r, uio);
121 		PROC_LOCK(p);
122 	}
123 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
124 		if (!P_SHOULDSTOP(p))
125 			error = EBUSY;
126 		else
127 			/* XXXKSE: */
128 			error = PROC(write, regs, td2, &r);
129 	}
130 	PROC_UNLOCK(p);
131 
132 	return (error);
133 }
134