xref: /freebsd/sys/fs/procfs/procfs_regs.c (revision 783d3ff6d7fae619db8a7990b8a6387de0c677b5)
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  * From:
36  *	$Id: procfs_regs.c,v 3.2 1993/12/15 09:40:17 jsp Exp $
37  */
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/proc.h>
44 #include <sys/ptrace.h>
45 #include <sys/uio.h>
46 
47 #include <fs/pseudofs/pseudofs.h>
48 #include <fs/procfs/procfs.h>
49 
50 #ifdef COMPAT_FREEBSD32
51 #include <sys/procfs.h>
52 #include <sys/sysent.h>
53 #include <machine/fpu.h>
54 
55 /*
56  * PROC(write, regs, td2, &r) becomes
57  * proc_write_regs(td2, &r)   or
58  * proc_write_regs32(td2, &r32)
59  *
60  * UIOMOVE_FROMBUF(r, uio) becomes
61  * uiomove_frombuf(&r, sizeof(r), uio)  or
62  * uiomove_frombuf(&r32, sizeof(r32), uio)
63  */
64 #define	PROC(d, w, t, r)	wrap32 ? \
65 	proc_ ## d ## _ ## w ## 32(t, r ## 32) : \
66 	proc_ ## d ## _ ## w(t, r)
67 #define	UIOMOVE_FROMBUF(k, u)	wrap32 ? \
68 	uiomove_frombuf(& k ## 32, sizeof(k ## 32), u) : \
69 	uiomove_frombuf(& k, sizeof(k), u)
70 #else
71 #define	PROC(d, w, t, r)	proc_ ## d ## _ ## w(t, r)
72 #define	UIOMOVE_FROMBUF(k, u)	uiomove_frombuf(& k, sizeof(k), u)
73 #endif
74 
75 int
76 procfs_doprocregs(PFS_FILL_ARGS)
77 {
78 	int error;
79 	struct reg r;
80 	struct thread *td2;
81 #ifdef COMPAT_FREEBSD32
82 	struct reg32 r32;
83 	int wrap32 = 0;
84 #endif
85 
86 	if (uio->uio_offset != 0)
87 		return (0);
88 
89 	PROC_LOCK(p);
90 	PROC_ASSERT_HELD(p);
91 	if (p_candebug(td, p)) {
92 		PROC_UNLOCK(p);
93 		return (EPERM);
94 	}
95 	if (!P_SHOULDSTOP(p)) {
96 		PROC_UNLOCK(p);
97 		return (EBUSY);
98 	}
99 
100 	td2 = FIRST_THREAD_IN_PROC(p);
101 #ifdef COMPAT_FREEBSD32
102 	if (SV_CURPROC_FLAG(SV_ILP32)) {
103 		if ((SV_PROC_FLAG(td2->td_proc, SV_ILP32)) == 0) {
104 			PROC_UNLOCK(p);
105 			return (EINVAL);
106 		}
107 		wrap32 = 1;
108 		memset(&r32, 0, sizeof(r32));
109 	} else
110 #endif
111 		memset(&r, 0, sizeof(r));
112 	error = PROC(read, regs, td2, &r);
113 	if (error == 0) {
114 		PROC_UNLOCK(p);
115 		error = UIOMOVE_FROMBUF(r, uio);
116 		PROC_LOCK(p);
117 	}
118 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
119 		if (!P_SHOULDSTOP(p))
120 			error = EBUSY;
121 		else
122 			/* XXXKSE: */
123 			error = PROC(write, regs, td2, &r);
124 	}
125 	PROC_UNLOCK(p);
126 
127 	return (error);
128 }
129