xref: /freebsd/sys/fs/procfs/procfs_dbregs.c (revision 031beb4e239bfce798af17f5fe8dba8bcaf13d99)
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  */
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/lock.h>
50 #include <sys/mutex.h>
51 #include <sys/proc.h>
52 #include <sys/ptrace.h>
53 #include <sys/uio.h>
54 
55 #include <fs/pseudofs/pseudofs.h>
56 #include <fs/procfs/procfs.h>
57 
58 #ifdef COMPAT_FREEBSD32
59 #include <sys/sysent.h>
60 #include <sys/procfs.h>
61 #include <machine/fpu.h>
62 
63 /*
64  * PROC(write, dbregs, td2, &r) becomes
65  * proc_write_dbregs(td2, &r)   or
66  * proc_write_dbregs32(td2, &r32)
67  *
68  * UIOMOVE_FROMBUF(r, uio) becomes
69  * uiomove_frombuf(&r, sizeof(r), uio)  or
70  * uiomove_frombuf(&r32, sizeof(r32), uio)
71  */
72 #define	PROC(d, w, t, r)	wrap32 ? \
73 	proc_ ## d ## _ ## w ## 32(t, r ## 32) : \
74 	proc_ ## d ## _ ## w(t, r)
75 #define	UIOMOVE_FROMBUF(k, u)	wrap32 ? \
76 	uiomove_frombuf(& k ## 32, sizeof(k ## 32), u) : \
77 	uiomove_frombuf(& k, sizeof(k), u)
78 #else
79 #define	PROC(d, w, t, r)	proc_ ## d ## _ ## w(t, r)
80 #define	UIOMOVE_FROMBUF(k, u)	uiomove_frombuf(& k, sizeof(k), u)
81 #endif
82 
83 int
84 procfs_doprocdbregs(PFS_FILL_ARGS)
85 {
86 	int error;
87 	struct dbreg r;
88 	struct thread *td2;
89 #ifdef COMPAT_FREEBSD32
90 	struct dbreg32 r32;
91 	int wrap32 = 0;
92 #endif
93 
94 	if (uio->uio_offset != 0)
95 		return (0);
96 
97 	PROC_LOCK(p);
98 	PROC_ASSERT_HELD(p);
99 	if (p_candebug(td, p) != 0) {
100 		PROC_UNLOCK(p);
101 		return (EPERM);
102 	}
103 
104 	td2 = FIRST_THREAD_IN_PROC(p);
105 #ifdef COMPAT_FREEBSD32
106 	if (SV_CURPROC_FLAG(SV_ILP32)) {
107 		if (SV_PROC_FLAG(td2->td_proc, SV_ILP32) == 0) {
108 			PROC_UNLOCK(p);
109 			return (EINVAL);
110 		}
111 		wrap32 = 1;
112 		memset(&r32, 0, sizeof(r32));
113 	} else
114 #endif
115 		memset(&r, 0, sizeof(r));
116 	error = PROC(read, dbregs, td2, &r);
117 	if (error == 0) {
118 		PROC_UNLOCK(p);
119 		error = UIOMOVE_FROMBUF(r, uio);
120 		PROC_LOCK(p);
121 	}
122 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
123 		if (!P_SHOULDSTOP(p)) /* XXXKSE should be P_TRACED? */
124 			error = EBUSY;
125 		else
126 			/* XXXKSE: */
127 			error = PROC(write, dbregs, td2, &r);
128 	}
129 	PROC_UNLOCK(p);
130 
131 	return (error);
132 }
133