xref: /netbsd-src/sys/compat/freebsd/freebsd_ptrace.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: freebsd_ptrace.c,v 1.19 2009/11/23 00:46:06 rmind Exp $	*/
2 
3 /*-
4  * Copyright (c) 1982, 1986, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	from: @(#)sys_process.c	8.1 (Berkeley) 6/10/93
37  */
38 
39 /*-
40  * Copyright (c) 1994 Christopher G. Demetriou.  All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *	This product includes software developed by the University of
53  *	California, Berkeley and its contributors.
54  * 4. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  *
70  *	from: @(#)sys_process.c	8.1 (Berkeley) 6/10/93
71  */
72 
73 #include <sys/cdefs.h>
74 __KERNEL_RCSID(0, "$NetBSD: freebsd_ptrace.c,v 1.19 2009/11/23 00:46:06 rmind Exp $");
75 
76 #include <sys/param.h>
77 #include <sys/systm.h>
78 #include <sys/proc.h>
79 #include <sys/errno.h>
80 #include <sys/ptrace.h>
81 #include <sys/uio.h>
82 #include <sys/mount.h>
83 #include <sys/syscall.h>
84 #include <sys/syscallargs.h>
85 
86 #include <compat/sys/signal.h>
87 #include <compat/sys/signalvar.h>
88 
89 #include <machine/reg.h>
90 #include <machine/freebsd_machdep.h>
91 
92 #include <compat/common/compat_util.h>
93 #include <compat/freebsd/freebsd_syscallargs.h>
94 #include <compat/freebsd/freebsd_ptrace.h>
95 
96 /*
97  * Process debugging system call.
98  */
99 int
100 freebsd_sys_ptrace(struct lwp *l, const struct freebsd_sys_ptrace_args *uap, register_t *retval)
101 {
102 	/* {
103 		syscallarg(int) req;
104 		syscallarg(pid_t) pid;
105 		syscallarg(void *) addr;
106 		syscallarg(int) data;
107 	} */
108 	struct sys_ptrace_args npa;
109 	sy_call_t *fn = sysent[SYS_ptrace].sy_call;
110 
111 	switch (SCARG(uap, req)) {
112 #ifdef PT_STEP
113 	case FREEBSD_PT_STEP:
114 		SCARG(&npa, req) = PT_STEP;
115 		SCARG(&npa, pid) = SCARG(uap, pid);
116 		SCARG(&npa, addr) = SCARG(uap, addr);
117 		SCARG(&npa, data) = SCARG(uap, data);
118 		return (*fn)(l, &npa, retval);
119 #endif
120 	case FREEBSD_PT_TRACE_ME:
121 	case FREEBSD_PT_READ_I:
122 	case FREEBSD_PT_READ_D:
123 	case FREEBSD_PT_WRITE_I:
124 	case FREEBSD_PT_WRITE_D:
125 	case FREEBSD_PT_CONTINUE:
126 	case FREEBSD_PT_KILL:
127 		/* These requests are compatible with NetBSD */
128 		return (*fn)(l, (const void *)uap, retval);
129 
130 #if 0
131 /*
132  * XXX: I've commented out this code, it is broken on too many fronts to fix.
133  *	1) It is doing an unlocked read-modify-write cycle on process that
134  *	   I assume might be running!
135  *	   and in code that might sleep (due to a pagefault), never mind
136  *	   what happens on an SMP system
137  *      2) It accesses data in userspace without using copyin/out.
138  *	3) It all looks like a nasty hack that isn't likely to work.
139  *	4) It uses the stackgap.
140  * dsl June 2007
141  */
142 	case FREEBSD_PT_READ_U:
143 	case FREEBSD_PT_WRITE_U:
144     {
145 	int error;
146 	struct {
147 		struct reg regs;
148 		struct fpreg fpregs;
149 	} *nrp;
150 	struct freebsd_ptrace_reg fr;
151 		sg = stackgap_init(p, 0);
152 		nrp = stackgap_alloc(p, &sg, sizeof(*nrp));
153 #ifdef PT_GETREGS
154 		SCARG(&npa, req) = PT_GETREGS;
155 		SCARG(&npa, pid) = SCARG(uap, pid);
156 		SCARG(&npa, addr) = (void *)&nrp->regs;
157 		if ((error = (*fn)(l, &npa, retval)) != 0)
158 			return error;
159 #endif
160 #ifdef PT_GETFPREGS
161 		SCARG(&npa, req) = PT_GETFPREGS;
162 		SCARG(&npa, pid) = SCARG(uap, pid);
163 		SCARG(&npa, addr) = (void *)&nrp->fpregs;
164 		if ((error = (*fn)(l, &npa, retval)) != 0)
165 			return error;
166 #endif
167 		netbsd_to_freebsd_ptrace_regs(&nrp->regs, &nrp->fpregs, &fr);
168 		switch (SCARG(uap, req)) {
169 		case FREEBSD_PT_READ_U:
170 			return freebsd_ptrace_getregs(&fr, SCARG(uap, addr),
171 						      retval);
172 
173 		case FREEBSD_PT_WRITE_U:
174 			error = freebsd_ptrace_setregs(&fr,
175 			    SCARG(uap, addr), SCARG(uap, data));
176 			if (error)
177 				return error;
178 			freebsd_to_netbsd_ptrace_regs(&fr,
179 						&nrp->regs, &nrp->fpregs);
180 #ifdef PT_SETREGS
181 			SCARG(&npa, req) = PT_SETREGS;
182 			SCARG(&npa, pid) = SCARG(uap, pid);
183 			SCARG(&npa, addr) = (void *)&nrp->regs;
184 			if ((error = (*fn)(l, &npa, retval)) != 0)
185 				return error;
186 #endif
187 #ifdef PT_SETFPREGS
188 			SCARG(&npa, req) = PT_SETFPREGS;
189 			SCARG(&npa, pid) = SCARG(uap, pid);
190 			SCARG(&npa, addr) = (void *)&nrp->fpregs;
191 			if ((error = (*fn)(l, &npa, retval)) != 0)
192 				return error;
193 #endif
194 			return 0;
195 		}
196     }
197 #endif
198 
199 	default:			/* It was not a legal request. */
200 		return (EINVAL);
201 	}
202 
203 #ifdef DIAGNOSTIC
204 	panic("freebsd_ptrace: impossible");
205 #endif
206 }
207