xref: /netbsd/sys/compat/linux/arch/arm/linux_ptrace.c (revision bf9ec67e)
1 /*	$NetBSD: linux_ptrace.c,v 1.2 2002/01/27 15:11:38 bjh21 Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Matthias Scheler.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 
40 #include <sys/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.2 2002/01/27 15:11:38 bjh21 Exp $");
42 
43 #include <sys/param.h>
44 #include <sys/malloc.h>
45 #include <sys/mount.h>
46 #include <sys/proc.h>
47 #include <sys/ptrace.h>
48 #include <sys/systm.h>
49 #include <sys/syscallargs.h>
50 #include <uvm/uvm_extern.h>
51 
52 #include <machine/reg.h>
53 
54 #include <compat/linux/common/linux_types.h>
55 #include <compat/linux/common/linux_ptrace.h>
56 #include <compat/linux/common/linux_signal.h>
57 
58 #include <compat/linux/common/linux_util.h>
59 #include <compat/linux/common/linux_machdep.h>
60 #include <compat/linux/common/linux_emuldata.h>
61 #include <compat/linux/common/linux_exec.h>	/* for emul_linux */
62 
63 #include <compat/linux/linux_syscallargs.h>
64 
65 #include <lib/libkern/libkern.h>	/* for offsetof() */
66 
67 /*
68  * On ARMv2, uregs contains R0--R15, orig_R0.
69  * On ARMv3 and later, it's R0--R15, CPSR, orig_R0.
70  * As far as I can see, Linux doesn't initialise orig_R0 on ARMv2, so we
71  * just produce the ARMv3 version.
72  */
73 
74 struct linux_reg {
75 	long uregs[18];
76 };
77 
78 #define LINUX_REG_R0	0
79 #define LINUX_REG_R1	1
80 #define LINUX_REG_R2	2
81 #define LINUX_REG_R3	3
82 #define LINUX_REG_R4	4
83 #define LINUX_REG_R5	5
84 #define LINUX_REG_R6	6
85 #define LINUX_REG_R7	7
86 #define LINUX_REG_R8	8
87 #define LINUX_REG_R9	9
88 #define LINUX_REG_R10	10
89 #define LINUX_REG_FP	11
90 #define LINUX_REG_IP	12
91 #define LINUX_REG_SP	13
92 #define LINUX_REG_LR	14
93 #define LINUX_REG_PC	15
94 #define LINUX_REG_CPSR	16
95 #define LINUX_REG_ORIG_R0 17
96 
97 /* Macros to clear/set/test flags. */
98 #define	SET(t, f)	(t) |= (f)
99 #define	CLR(t, f)	(t) &= ~(f)
100 #define	ISSET(t, f)	((t) & (f))
101 
102 int
103 linux_sys_ptrace_arch(p, v, retval)
104 	struct proc *p;
105 	void *v;
106 	register_t *retval;
107 {
108 	struct linux_sys_ptrace_args /* {
109 		syscallarg(int) request;
110 		syscallarg(int) pid;
111 		syscallarg(int) addr;
112 		syscallarg(int) data;
113 	} */ *uap = v;
114 	int request, error;
115 	struct proc *t;				/* target process */
116 	struct reg *regs = NULL;
117 	struct fpreg *fpregs = NULL;
118 	struct linux_reg *linux_regs = NULL;
119 	struct linux_fpreg *linux_fpregs = NULL;
120 
121 	request = SCARG(uap, request);
122 
123 	if ((request != LINUX_PTRACE_GETREGS) &&
124 	    (request != LINUX_PTRACE_SETREGS))
125 		return EIO;
126 
127 	/* Find the process we're supposed to be operating on. */
128 	if ((t = pfind(SCARG(uap, pid))) == NULL)
129 		return ESRCH;
130 
131 	/*
132 	 * You can't do what you want to the process if:
133 	 *	(1) It's not being traced at all,
134 	 */
135 	if (!ISSET(t->p_flag, P_TRACED))
136 		return EPERM;
137 
138 	/*
139 	 *	(2) it's being traced by procfs (which has
140 	 *	    different signal delivery semantics),
141 	 */
142 	if (ISSET(t->p_flag, P_FSTRACE))
143 		return EBUSY;
144 
145 	/*
146 	 *	(3) it's not being traced by _you_, or
147 	 */
148 	if (t->p_pptr != p)
149 		return EBUSY;
150 
151 	/*
152 	 *	(4) it's not currently stopped.
153 	 */
154 	if (t->p_stat != SSTOP || !ISSET(t->p_flag, P_WAITED))
155 		return EBUSY;
156 
157 	*retval = 0;
158 
159 	switch (request) {
160 	case  LINUX_PTRACE_GETREGS:
161 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
162 		MALLOC(linux_regs, struct linux_reg*, sizeof(struct linux_reg),
163 			M_TEMP, M_WAITOK);
164 
165 		error = process_read_regs(t, regs);
166 		if (error != 0)
167 			goto out;
168 
169 		memcpy(linux_regs->uregs, regs->r, 13 * sizeof(register_t));
170 		linux_regs->uregs[LINUX_REG_SP] = regs->r_sp;
171 		linux_regs->uregs[LINUX_REG_LR] = regs->r_lr;
172 		linux_regs->uregs[LINUX_REG_PC] = regs->r_pc;
173 		linux_regs->uregs[LINUX_REG_CPSR] = regs->r_cpsr;
174 		linux_regs->uregs[LINUX_REG_ORIG_R0] = regs->r[0];
175 
176 		error = copyout(linux_regs, (caddr_t)SCARG(uap, data),
177 		    sizeof(struct linux_reg));
178 		goto out;
179 
180 	case  LINUX_PTRACE_SETREGS:
181 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
182 		MALLOC(linux_regs, struct linux_reg *, sizeof(struct linux_reg),
183 			M_TEMP, M_WAITOK);
184 
185 		error = copyin((caddr_t)SCARG(uap, data), linux_regs,
186 		    sizeof(struct linux_reg));
187 		if (error != 0)
188 			goto out;
189 
190 		memcpy(regs->r, linux_regs->uregs, 13 * sizeof(register_t));
191 		regs->r_sp = linux_regs->uregs[LINUX_REG_SP];
192 		regs->r_lr = linux_regs->uregs[LINUX_REG_LR];
193 		regs->r_pc = linux_regs->uregs[LINUX_REG_PC];
194 		regs->r_cpsr = linux_regs->uregs[LINUX_REG_CPSR];
195 
196 		error = process_write_regs(t, regs);
197 		goto out;
198 
199 	default:
200 		/* never reached */
201 		break;
202 	}
203 
204 	return EIO;
205 
206     out:
207 	if (regs)
208 		FREE(regs, M_TEMP);
209 	if (fpregs)
210 		FREE(fpregs, M_TEMP);
211 	if (linux_regs)
212 		FREE(linux_regs, M_TEMP);
213 	if (linux_fpregs)
214 		FREE(linux_fpregs, M_TEMP);
215 	return (error);
216 
217 }
218