xref: /freebsd/sys/fs/procfs/procfs_dbregs.c (revision cd0d51baaa4509a1db83251a601d34404d20c990)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1999 Brian Scott Dean, brdean@unx.sas.com.
5  *                    All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Jan-Simon Pendry under the following copyrights and conditions:
9  *
10  * Copyright (c) 1993 Jan-Simon Pendry
11  * Copyright (c) 1993
12  *	The Regents of the University of California.  All rights reserved.
13  *
14  * This code is derived from software contributed to Berkeley by
15  * Jan-Simon Pendry.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  * 3. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	From: @(#)procfs_regs.c	8.4 (Berkeley) 6/15/94
42  *
43  * From:
44  *	$Id: procfs_regs.c,v 3.2 1993/12/15 09:40:17 jsp Exp $
45  * $FreeBSD$
46  */
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/lock.h>
51 #include <sys/mutex.h>
52 #include <sys/proc.h>
53 #include <sys/ptrace.h>
54 #include <sys/sysent.h>
55 #include <sys/uio.h>
56 
57 #include <machine/reg.h>
58 
59 #include <fs/pseudofs/pseudofs.h>
60 #include <fs/procfs/procfs.h>
61 
62 #ifdef COMPAT_FREEBSD32
63 #include <sys/procfs.h>
64 #include <machine/fpu.h>
65 
66 /*
67  * PROC(write, dbregs, td2, &r) becomes
68  * proc_write_dbregs(td2, &r)   or
69  * proc_write_dbregs32(td2, &r32)
70  *
71  * UIOMOVE_FROMBUF(r, uio) becomes
72  * uiomove_frombuf(&r, sizeof(r), uio)  or
73  * uiomove_frombuf(&r32, sizeof(r32), uio)
74  */
75 #define	PROC(d, w, t, r)	wrap32 ? \
76 	proc_ ## d ## _ ## w ## 32(t, r ## 32) : \
77 	proc_ ## d ## _ ## w(t, r)
78 #define	UIOMOVE_FROMBUF(k, u)	wrap32 ? \
79 	uiomove_frombuf(& k ## 32, sizeof(k ## 32), u) : \
80 	uiomove_frombuf(& k, sizeof(k), u)
81 #else
82 #define	PROC(d, w, t, r)	proc_ ## d ## _ ## w(t, r)
83 #define	UIOMOVE_FROMBUF(k, u)	uiomove_frombuf(& k, sizeof(k), u)
84 #endif
85 
86 int
87 procfs_doprocdbregs(PFS_FILL_ARGS)
88 {
89 	int error;
90 	struct dbreg r;
91 	struct thread *td2;
92 #ifdef COMPAT_FREEBSD32
93 	struct dbreg32 r32;
94 	int wrap32 = 0;
95 #endif
96 
97 	if (uio->uio_offset != 0)
98 		return (0);
99 
100 	PROC_LOCK(p);
101 	PROC_ASSERT_HELD(p);
102 	if (p_candebug(td, p) != 0) {
103 		PROC_UNLOCK(p);
104 		return (EPERM);
105 	}
106 
107 	td2 = FIRST_THREAD_IN_PROC(p);
108 #ifdef COMPAT_FREEBSD32
109 	if (SV_CURPROC_FLAG(SV_ILP32)) {
110 		if (SV_PROC_FLAG(td2->td_proc, SV_ILP32) == 0) {
111 			PROC_UNLOCK(p);
112 			return (EINVAL);
113 		}
114 		wrap32 = 1;
115 		memset(&r32, 0, sizeof(r32));
116 	} else
117 #endif
118 		memset(&r, 0, sizeof(r));
119 	error = PROC(read, dbregs, td2, &r);
120 	if (error == 0) {
121 		PROC_UNLOCK(p);
122 		error = UIOMOVE_FROMBUF(r, uio);
123 		PROC_LOCK(p);
124 	}
125 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
126 		if (!P_SHOULDSTOP(p)) /* XXXKSE should be P_TRACED? */
127 			error = EBUSY;
128 		else
129 			/* XXXKSE: */
130 			error = PROC(write, dbregs, td2, &r);
131 	}
132 	PROC_UNLOCK(p);
133 
134 	return (error);
135 }
136