xref: /netbsd-src/sys/compat/linux/arch/arm/linux_ptrace.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: linux_ptrace.c,v 1.3 2003/01/18 08:02:47 thorpej 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 1.3 2003/01/18 08:02:47 thorpej 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/sa.h>
50 #include <sys/syscallargs.h>
51 #include <uvm/uvm_extern.h>
52 
53 #include <machine/reg.h>
54 
55 #include <compat/linux/common/linux_types.h>
56 #include <compat/linux/common/linux_ptrace.h>
57 #include <compat/linux/common/linux_signal.h>
58 
59 #include <compat/linux/common/linux_util.h>
60 #include <compat/linux/common/linux_machdep.h>
61 #include <compat/linux/common/linux_emuldata.h>
62 #include <compat/linux/common/linux_exec.h>	/* for emul_linux */
63 
64 #include <compat/linux/linux_syscallargs.h>
65 
66 #include <lib/libkern/libkern.h>	/* for offsetof() */
67 
68 /*
69  * On ARMv2, uregs contains R0--R15, orig_R0.
70  * On ARMv3 and later, it's R0--R15, CPSR, orig_R0.
71  * As far as I can see, Linux doesn't initialise orig_R0 on ARMv2, so we
72  * just produce the ARMv3 version.
73  */
74 
75 struct linux_reg {
76 	long uregs[18];
77 };
78 
79 #define LINUX_REG_R0	0
80 #define LINUX_REG_R1	1
81 #define LINUX_REG_R2	2
82 #define LINUX_REG_R3	3
83 #define LINUX_REG_R4	4
84 #define LINUX_REG_R5	5
85 #define LINUX_REG_R6	6
86 #define LINUX_REG_R7	7
87 #define LINUX_REG_R8	8
88 #define LINUX_REG_R9	9
89 #define LINUX_REG_R10	10
90 #define LINUX_REG_FP	11
91 #define LINUX_REG_IP	12
92 #define LINUX_REG_SP	13
93 #define LINUX_REG_LR	14
94 #define LINUX_REG_PC	15
95 #define LINUX_REG_CPSR	16
96 #define LINUX_REG_ORIG_R0 17
97 
98 /* Macros to clear/set/test flags. */
99 #define	SET(t, f)	(t) |= (f)
100 #define	CLR(t, f)	(t) &= ~(f)
101 #define	ISSET(t, f)	((t) & (f))
102 
103 int
104 linux_sys_ptrace_arch(l, v, retval)
105 	struct lwp *l;
106 	void *v;
107 	register_t *retval;
108 {
109 	struct linux_sys_ptrace_args /* {
110 		syscallarg(int) request;
111 		syscallarg(int) pid;
112 		syscallarg(int) addr;
113 		syscallarg(int) data;
114 	} */ *uap = v;
115 	struct proc *p = l->l_proc;
116 	int request, error;
117 	struct proc *t;				/* target process */
118 	struct lwp *lt;
119 	struct reg *regs = NULL;
120 	struct fpreg *fpregs = NULL;
121 	struct linux_reg *linux_regs = NULL;
122 	struct linux_fpreg *linux_fpregs = NULL;
123 
124 	request = SCARG(uap, request);
125 
126 	if ((request != LINUX_PTRACE_GETREGS) &&
127 	    (request != LINUX_PTRACE_SETREGS))
128 		return EIO;
129 
130 	/* Find the process we're supposed to be operating on. */
131 	if ((t = pfind(SCARG(uap, pid))) == NULL)
132 		return ESRCH;
133 
134 	/*
135 	 * You can't do what you want to the process if:
136 	 *	(1) It's not being traced at all,
137 	 */
138 	if (!ISSET(t->p_flag, P_TRACED))
139 		return EPERM;
140 
141 	/*
142 	 *	(2) it's being traced by procfs (which has
143 	 *	    different signal delivery semantics),
144 	 */
145 	if (ISSET(t->p_flag, P_FSTRACE))
146 		return EBUSY;
147 
148 	/*
149 	 *	(3) it's not being traced by _you_, or
150 	 */
151 	if (t->p_pptr != p)
152 		return EBUSY;
153 
154 	/*
155 	 *	(4) it's not currently stopped.
156 	 */
157 	if (t->p_stat != SSTOP || !ISSET(t->p_flag, P_WAITED))
158 		return EBUSY;
159 
160 	/* XXX NJWLWP
161 	 * The entire ptrace interface needs work to be useful to
162 	 * a process with multiple LWPs. For the moment, we'll
163 	 * just kluge this and fail on others.
164 	 */
165 
166 	if (p->p_nlwps > 1)
167 		return (ENOSYS);
168 
169 	lt = LIST_FIRST(&t->p_lwps);
170 
171 	*retval = 0;
172 
173 	switch (request) {
174 	case  LINUX_PTRACE_GETREGS:
175 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
176 		MALLOC(linux_regs, struct linux_reg*, sizeof(struct linux_reg),
177 			M_TEMP, M_WAITOK);
178 
179 		error = process_read_regs(lt, regs);
180 		if (error != 0)
181 			goto out;
182 
183 		memcpy(linux_regs->uregs, regs->r, 13 * sizeof(register_t));
184 		linux_regs->uregs[LINUX_REG_SP] = regs->r_sp;
185 		linux_regs->uregs[LINUX_REG_LR] = regs->r_lr;
186 		linux_regs->uregs[LINUX_REG_PC] = regs->r_pc;
187 		linux_regs->uregs[LINUX_REG_CPSR] = regs->r_cpsr;
188 		linux_regs->uregs[LINUX_REG_ORIG_R0] = regs->r[0];
189 
190 		error = copyout(linux_regs, (caddr_t)SCARG(uap, data),
191 		    sizeof(struct linux_reg));
192 		goto out;
193 
194 	case  LINUX_PTRACE_SETREGS:
195 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
196 		MALLOC(linux_regs, struct linux_reg *, sizeof(struct linux_reg),
197 			M_TEMP, M_WAITOK);
198 
199 		error = copyin((caddr_t)SCARG(uap, data), linux_regs,
200 		    sizeof(struct linux_reg));
201 		if (error != 0)
202 			goto out;
203 
204 		memcpy(regs->r, linux_regs->uregs, 13 * sizeof(register_t));
205 		regs->r_sp = linux_regs->uregs[LINUX_REG_SP];
206 		regs->r_lr = linux_regs->uregs[LINUX_REG_LR];
207 		regs->r_pc = linux_regs->uregs[LINUX_REG_PC];
208 		regs->r_cpsr = linux_regs->uregs[LINUX_REG_CPSR];
209 
210 		error = process_write_regs(lt, regs);
211 		goto out;
212 
213 	default:
214 		/* never reached */
215 		break;
216 	}
217 
218 	return EIO;
219 
220     out:
221 	if (regs)
222 		FREE(regs, M_TEMP);
223 	if (fpregs)
224 		FREE(fpregs, M_TEMP);
225 	if (linux_regs)
226 		FREE(linux_regs, M_TEMP);
227 	if (linux_fpregs)
228 		FREE(linux_fpregs, M_TEMP);
229 	return (error);
230 
231 }
232