xref: /netbsd-src/sys/compat/linux/arch/powerpc/linux_ptrace.c (revision 06be8101a16cc95f40783b3cb7afd12112103a9a)
1 /*	$NetBSD: linux_ptrace.c,v 1.8 2001/11/13 02:08:46 lukem Exp $ */
2 
3 /*-
4  * Copyright (c) 1999, 2001 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 and Emmanuel Dreyfus.
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 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: linux_ptrace.c,v 1.8 2001/11/13 02:08:46 lukem Exp $");
41 
42 #include <sys/types.h>
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  * From Linux's include/asm-ppc/ptrace.h.
69  * structure used for storing reg context:  defined in linux_machdep.h
70  * structure used for storing floating point context:
71  * Linux just uses a double fpr[32], no struct
72  */
73 
74 /*
75  * user struct for linux process - this is used for Linux ptrace emulation
76  * most of it is junk only used by gdb
77  *
78  * From Linux's include/asm-ppc/user.h
79  *
80  * XXX u_ar0 was a struct reg in Linux/powerpc
81  * Can't find out what a struct regs is for Linux/powerpc,
82  * so we use a struct pt_regs instead. don't know if this is right.
83  */
84 
85 struct linux_user {
86 	struct linux_pt_regs regs;
87 #define lusr_startgdb regs
88 	size_t u_tsize;
89 	size_t u_dsize;
90 	size_t u_ssize;
91 	unsigned long start_code;
92 	unsigned long start_data;
93 	unsigned long start_stack;
94 	long int signal;
95 	struct linux_pt_regs *u_ar0;		/* help gdb find registers */
96 	unsigned long magic;
97 	char u_comm[32];
98 #define lu_comm_end u_comm[31]
99 };
100 
101 #define LUSR_OFF(member) offsetof(struct linux_user, member)
102 #define LUSR_REG_OFF(member) offsetof(struct linux_pt_regs, member)
103 #define ISSET(t, f) ((t) & (f))
104 
105 int
106 linux_sys_ptrace_arch(p, v, retval)	/* XXX Check me! (From NetBSD/i386) */
107 	struct proc *p;
108 	void *v;
109 	register_t *retval;
110 {
111 	struct linux_sys_ptrace_args /* {
112 		syscallarg(int) request;
113 		syscallarg(int) pid;
114 		syscallarg(int) addr;
115 		syscallarg(int) data;
116 	} */ *uap = v;
117 	int request, error;
118 	struct proc *t;				/* target process */
119 	struct reg *regs = NULL;
120 	struct fpreg *fpregs = NULL;
121 	struct linux_pt_regs *linux_regs = NULL;
122 	double *linux_fpreg = NULL;  /* it's an array, not a struct */
123 	int addr;
124 	int i;
125 
126 	switch (request = SCARG(uap, request)) {
127 		case LINUX_PTRACE_PEEKUSR:
128 		case LINUX_PTRACE_POKEUSR:
129 		case LINUX_PTRACE_GETREGS:
130 		case LINUX_PTRACE_SETREGS:
131 		case LINUX_PTRACE_GETFPREGS:
132 		case LINUX_PTRACE_SETFPREGS:
133 			break;
134 		default:
135 			return EIO;
136 	}
137 
138 	/* Find the process we're supposed to be operating on. */
139 	if ((t = pfind(SCARG(uap, pid))) == NULL)
140 		return ESRCH;
141 
142 	/*
143 	 * You can't do what you want to the process if:
144 	 *	(1) It's not being traced at all,
145 	 */
146 	if (!ISSET(t->p_flag, P_TRACED))
147 		return EPERM;
148 
149 	/*
150 	 *	(2) it's being traced by procfs (which has
151 	 *		 different signal delivery semantics),
152 	 */
153 	if (ISSET(t->p_flag, P_FSTRACE))
154 		return EBUSY;
155 
156 	/*
157 	 *	(3) it's not being traced by _you_, or
158 	 */
159 	if (t->p_pptr != p)
160 		return EBUSY;
161 
162 	/*
163 	 *	(4) it's not currently stopped.
164 	 */
165 	if (t->p_stat != SSTOP || !ISSET(t->p_flag, P_WAITED))
166 		return EBUSY;
167 
168 	*retval = 0;
169 
170 	switch (request) {
171 	case  LINUX_PTRACE_GETREGS:
172 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
173 		MALLOC(linux_regs, struct linux_pt_regs*, sizeof(*linux_regs),
174 		    M_TEMP, M_WAITOK);
175 
176 		error = process_read_regs(t, regs);
177 		if (error != 0)
178 			goto out;
179 
180 		for (i=0; i<=31; i++)
181 			linux_regs->lgpr[i] = regs->fixreg[i];
182 		linux_regs->lnip = regs->pc;
183 		linux_regs->lmsr = 0;
184 		/* XXX Is that right? */
185 		linux_regs->lorig_gpr3 = regs->fixreg[3];
186 		linux_regs->lctr = regs->ctr;
187 		linux_regs->llink = regs->lr;
188 		linux_regs->lxer = regs->xer;
189 		linux_regs->lccr = regs->cr;
190 		linux_regs->lmq = 0;
191 		linux_regs->ltrap = 0;
192 		linux_regs->ldar = 0;
193 		linux_regs->ldsisr = 0;
194 		linux_regs->lresult = 0;
195 
196 		error = copyout(linux_regs, (caddr_t)SCARG(uap, data),
197 			 sizeof(struct linux_pt_regs));
198 		goto out;
199 
200 	case  LINUX_PTRACE_SETREGS:
201 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
202 		MALLOC(linux_regs, struct linux_pt_regs*, sizeof(*linux_regs),
203 		    M_TEMP, M_WAITOK);
204 
205 		error = copyin((caddr_t)SCARG(uap, data), linux_regs,
206 			 sizeof(struct linux_pt_regs));
207 		if (error != 0)
208 			goto out;
209 
210 		for (i=0; i<=31; i++)
211 			regs->fixreg[i] = linux_regs->lgpr[i];
212 		regs->lr = linux_regs->llink;
213 		regs->cr = linux_regs->lccr;
214 		regs->xer = linux_regs->lxer;
215 		regs->ctr = linux_regs->lctr;
216 		regs->pc = linux_regs->lnip; /* XXX */
217 
218 		error = process_write_regs(t, regs);
219 		goto out;
220 
221 	case  LINUX_PTRACE_GETFPREGS:
222 		MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg),
223 		    M_TEMP, M_WAITOK);
224 		MALLOC(linux_fpreg, double *,
225 		    32*sizeof(double), M_TEMP, M_WAITOK);
226 
227 		error = process_read_fpregs(t, fpregs);
228 		if (error != 0)
229 			goto out;
230 
231 		/* zero the contents if NetBSD fpreg structure is smaller */
232 		if (sizeof(struct fpreg) < (32*sizeof(double)))
233 			memset(linux_fpreg, '\0', (32*sizeof(double)));
234 
235 		memcpy(linux_fpreg, fpregs,
236 			min(32*sizeof(double), sizeof(struct fpreg)));
237 		error = copyout(linux_fpreg, (caddr_t)SCARG(uap, data),
238 			 32*sizeof(double));
239 		goto out;
240 
241 	case  LINUX_PTRACE_SETFPREGS:
242 		MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg),
243 		    M_TEMP, M_WAITOK);
244 		MALLOC(linux_fpreg, double *,
245 		    32*sizeof(double), M_TEMP, M_WAITOK);
246 		error = copyin((caddr_t)SCARG(uap, data), linux_fpreg,
247 			 32*sizeof(double));
248 		if (error != 0)
249 			goto out;
250 
251 		memset(fpregs, '\0', sizeof(struct fpreg));
252 		memcpy(fpregs, linux_fpreg,
253 		    min(32*sizeof(double), sizeof(struct fpreg)));
254 
255 		error = process_write_fpregs(t, fpregs);
256 		goto out;
257 
258 	case  LINUX_PTRACE_PEEKUSR:
259 		addr = SCARG(uap, addr);
260 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
261 		error = process_read_regs(t, regs);
262 		if (error)
263 			goto out;
264 
265 		PHOLD(t);	/* need full process info */
266 		error = 0;
267 		if ((addr < LUSR_OFF(lusr_startgdb)) ||
268 		    (addr > LUSR_OFF(lu_comm_end)))
269 		 	error = 1;
270 		else if (addr == LUSR_OFF(u_tsize))
271 			*retval = p->p_vmspace->vm_tsize;
272 		else if (addr == LUSR_OFF(u_dsize))
273 			*retval = p->p_vmspace->vm_dsize;
274 		else if (addr == LUSR_OFF(u_ssize))
275 			*retval = p->p_vmspace->vm_ssize;
276 		else if (addr == LUSR_OFF(start_code))
277 			*retval = (register_t) p->p_vmspace->vm_taddr;
278 		else if (addr == LUSR_OFF(start_stack))
279 			*retval = (register_t) p->p_vmspace->vm_minsaddr;
280 		else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) &&
281 		    (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end)))
282 			*retval = regs->fixreg[addr / sizeof (register_t)];
283 		else if (addr == LUSR_REG_OFF(lnip))
284 			*retval = regs->pc;
285 		else if (addr == LUSR_REG_OFF(lctr))
286 			*retval = regs->ctr;
287 		else if (addr == LUSR_REG_OFF(llink))
288 			*retval = regs->lr;
289 		else if (addr == LUSR_REG_OFF(lxer))
290 			*retval = regs->xer;
291 		else if (addr == LUSR_REG_OFF(lccr))
292 			*retval = regs->cr;
293 		else if (addr == LUSR_OFF(signal))
294 			error = 1;
295 		else if (addr == LUSR_OFF(signal))
296 			error = 1;
297 		else if (addr == LUSR_OFF(magic))
298 			error = 1;
299 		else if (addr == LUSR_OFF(u_comm))
300 			error = 1;
301 		else {
302 #ifdef DEBUG_LINUX
303 			printf("linux_ptrace: unsupported address: %d\n", addr);
304 #endif
305 			error = 1;
306 		}
307 
308 		PRELE(t);
309 
310 		if (error)
311 			goto out;
312 
313 		error = copyout (retval,
314 		    (caddr_t)SCARG(uap, data), sizeof retval);
315 		*retval = SCARG(uap, data);
316 
317 		goto out;
318 
319 		break;
320 
321 	case  LINUX_PTRACE_POKEUSR: /* XXX Not tested */
322 		addr = SCARG(uap, addr);
323 		MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
324 		error = process_read_regs(t, regs);
325 		if (error)
326 			goto out;
327 
328 		PHOLD(t);       /* need full process info */
329 		error = 0;
330 		if ((addr < LUSR_OFF(lusr_startgdb)) ||
331 		    (addr > LUSR_OFF(lu_comm_end)))
332 		 	error = 1;
333 		else if (addr == LUSR_OFF(u_tsize))
334 			error = 1;
335 		else if (addr == LUSR_OFF(u_dsize))
336 			error = 1;
337 		else if (addr == LUSR_OFF(u_ssize))
338 			error = 1;
339 		else if (addr == LUSR_OFF(start_code))
340 			error = 1;
341 		else if (addr == LUSR_OFF(start_stack))
342 			error = 1;
343 		else if ((addr >= LUSR_REG_OFF(lpt_regs_fixreg_begin)) &&
344 		    (addr <= LUSR_REG_OFF(lpt_regs_fixreg_end)))
345 			regs->fixreg[addr / sizeof (register_t)] =
346 			    (register_t)SCARG(uap, data);
347 		else if (addr == LUSR_REG_OFF(lnip))
348 			regs->pc = (register_t)SCARG(uap, data);
349 		else if (addr == LUSR_REG_OFF(lctr))
350 			regs->ctr = (register_t)SCARG(uap, data);
351 		else if (addr == LUSR_REG_OFF(llink))
352 			regs->lr = (register_t)SCARG(uap, data);
353 		else if (addr == LUSR_REG_OFF(lxer))
354 			regs->xer = (register_t)SCARG(uap, data);
355 		else if (addr == LUSR_REG_OFF(lccr))
356 			regs->cr = (register_t)SCARG(uap, data);
357 		else if (addr == LUSR_OFF(signal))
358 			error = 1;
359 		else if (addr == LUSR_OFF(magic))
360 			error = 1;
361 		else if (addr == LUSR_OFF(u_comm))
362 			error = 1;
363 		else {
364 #ifdef DEBUG_LINUX
365 			printf("linux_ptrace: unsupported address: %d\n", addr);
366 #endif
367 			error = 1;
368 		}
369 
370 		PRELE(t);
371 
372 		error = process_write_regs(t,regs);
373 		if (error)
374 			goto out;
375 
376 		break;
377 	default:
378 		/* never reached */
379 		break;
380 	}
381 	return EIO;
382 
383 	 out:
384 	if (regs)
385 		FREE(regs, M_TEMP);
386 	if (fpregs)
387 		FREE(fpregs, M_TEMP);
388 	if (linux_regs)
389 		FREE(linux_regs, M_TEMP);
390 	if (linux_fpreg)
391 		FREE(linux_fpreg, M_TEMP);
392 	return (error);
393 }
394