ptrace.c 24.3 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
/*
 *  arch/s390/kernel/ptrace.c
 *
 *  S390 version
 *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 *  Based on PowerPC version 
 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 *
 *  Derived from "arch/m68k/kernel/ptrace.c"
 *  Copyright (C) 1994 by Hamish Macdonald
 *  Taken from linux/kernel/ptrace.c and modified for M680x0.
 *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
 *
 * Modified by Cort Dougan (cort@cs.nmt.edu) 
 *
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License.  See the file README.legal in the main directory of
 * this archive for more details.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/audit.h>
35
#include <linux/signal.h>
36 37
#include <linux/elf.h>
#include <linux/regset.h>
Martin Schwidefsky's avatar
Martin Schwidefsky committed
38
#include <linux/tracehook.h>
Linus Torvalds's avatar
Linus Torvalds committed
39 40 41 42 43 44 45

#include <asm/segment.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/system.h>
#include <asm/uaccess.h>
46
#include <asm/unistd.h>
47
#include "entry.h"
Linus Torvalds's avatar
Linus Torvalds committed
48

49
#ifdef CONFIG_COMPAT
Linus Torvalds's avatar
Linus Torvalds committed
50 51 52
#include "compat_ptrace.h"
#endif

53 54 55 56 57
enum s390_regset {
	REGSET_GENERAL,
	REGSET_FP,
};

Linus Torvalds's avatar
Linus Torvalds committed
58 59 60 61 62 63
static void
FixPerRegisters(struct task_struct *task)
{
	struct pt_regs *regs;
	per_struct *per_info;

Al Viro's avatar
Al Viro committed
64
	regs = task_pt_regs(task);
Linus Torvalds's avatar
Linus Torvalds committed
65 66 67 68 69 70
	per_info = (per_struct *) &task->thread.per_info;
	per_info->control_regs.bits.em_instruction_fetch =
		per_info->single_step | per_info->instruction_fetch;
	
	if (per_info->single_step) {
		per_info->control_regs.bits.starting_addr = 0;
71
#ifdef CONFIG_COMPAT
Linus Torvalds's avatar
Linus Torvalds committed
72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
		if (test_thread_flag(TIF_31BIT))
			per_info->control_regs.bits.ending_addr = 0x7fffffffUL;
		else
#endif
			per_info->control_regs.bits.ending_addr = PSW_ADDR_INSN;
	} else {
		per_info->control_regs.bits.starting_addr =
			per_info->starting_addr;
		per_info->control_regs.bits.ending_addr =
			per_info->ending_addr;
	}
	/*
	 * if any of the control reg tracing bits are on 
	 * we switch on per in the psw
	 */
	if (per_info->control_regs.words.cr[0] & PER_EM_MASK)
		regs->psw.mask |= PSW_MASK_PER;
	else
		regs->psw.mask &= ~PSW_MASK_PER;

	if (per_info->control_regs.bits.em_storage_alteration)
		per_info->control_regs.bits.storage_alt_space_ctl = 1;
	else
		per_info->control_regs.bits.storage_alt_space_ctl = 0;
}

Roland McGrath's avatar
Roland McGrath committed
98
void user_enable_single_step(struct task_struct *task)
Linus Torvalds's avatar
Linus Torvalds committed
99 100 101 102 103
{
	task->thread.per_info.single_step = 1;
	FixPerRegisters(task);
}

Roland McGrath's avatar
Roland McGrath committed
104
void user_disable_single_step(struct task_struct *task)
Linus Torvalds's avatar
Linus Torvalds committed
105 106 107 108 109 110 111 112 113 114 115 116 117 118
{
	task->thread.per_info.single_step = 0;
	FixPerRegisters(task);
}

/*
 * Called by kernel/ptrace.c when detaching..
 *
 * Make sure single step bits etc are not set.
 */
void
ptrace_disable(struct task_struct *child)
{
	/* make sure the single step bit is not set. */
Roland McGrath's avatar
Roland McGrath committed
119
	user_disable_single_step(child);
Linus Torvalds's avatar
Linus Torvalds committed
120 121
}

122
#ifndef CONFIG_64BIT
Linus Torvalds's avatar
Linus Torvalds committed
123 124 125 126 127 128 129 130 131 132 133 134 135 136
# define __ADDR_MASK 3
#else
# define __ADDR_MASK 7
#endif

/*
 * Read the word at offset addr from the user area of a process. The
 * trouble here is that the information is littered over different
 * locations. The process registers are found on the kernel stack,
 * the floating point stuff and the trace settings are stored in
 * the task structure. In addition the different structures in
 * struct user contain pad bytes that should be read as zeroes.
 * Lovely...
 */
137
static unsigned long __peek_user(struct task_struct *child, addr_t addr)
Linus Torvalds's avatar
Linus Torvalds committed
138 139
{
	struct user *dummy = NULL;
140
	addr_t offset, tmp;
Linus Torvalds's avatar
Linus Torvalds committed
141 142 143 144 145

	if (addr < (addr_t) &dummy->regs.acrs) {
		/*
		 * psw and gprs are stored on the stack
		 */
Al Viro's avatar
Al Viro committed
146
		tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
Linus Torvalds's avatar
Linus Torvalds committed
147 148 149 150 151 152 153 154 155
		if (addr == (addr_t) &dummy->regs.psw.mask)
			/* Remove per bit from user psw. */
			tmp &= ~PSW_MASK_PER;

	} else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
		/*
		 * access registers are stored in the thread structure
		 */
		offset = addr - (addr_t) &dummy->regs.acrs;
156
#ifdef CONFIG_64BIT
157 158 159 160 161 162 163 164 165
		/*
		 * Very special case: old & broken 64 bit gdb reading
		 * from acrs[15]. Result is a 64 bit value. Read the
		 * 32 bit acrs[15] value and shift it by 32. Sick...
		 */
		if (addr == (addr_t) &dummy->regs.acrs[15])
			tmp = ((unsigned long) child->thread.acrs[15]) << 32;
		else
#endif
Linus Torvalds's avatar
Linus Torvalds committed
166 167 168 169 170 171
		tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);

	} else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
		/*
		 * orig_gpr2 is stored on the kernel stack
		 */
Al Viro's avatar
Al Viro committed
172
		tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
Linus Torvalds's avatar
Linus Torvalds committed
173

174 175 176 177 178 179 180
	} else if (addr < (addr_t) &dummy->regs.fp_regs) {
		/*
		 * prevent reads of padding hole between
		 * orig_gpr2 and fp_regs on s390.
		 */
		tmp = 0;

Linus Torvalds's avatar
Linus Torvalds committed
181 182 183 184 185 186
	} else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
		/* 
		 * floating point regs. are stored in the thread structure
		 */
		offset = addr - (addr_t) &dummy->regs.fp_regs;
		tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
187 188 189
		if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
			tmp &= (unsigned long) FPC_VALID_MASK
				<< (BITS_PER_LONG - 32);
Linus Torvalds's avatar
Linus Torvalds committed
190 191 192 193 194 195 196 197 198 199 200

	} else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
		/*
		 * per_info is found in the thread structure
		 */
		offset = addr - (addr_t) &dummy->regs.per_info;
		tmp = *(addr_t *)((addr_t) &child->thread.per_info + offset);

	} else
		tmp = 0;

201
	return tmp;
Linus Torvalds's avatar
Linus Torvalds committed
202 203 204
}

static int
205
peek_user(struct task_struct *child, addr_t addr, addr_t data)
Linus Torvalds's avatar
Linus Torvalds committed
206 207
{
	struct user *dummy = NULL;
208
	addr_t tmp, mask;
Linus Torvalds's avatar
Linus Torvalds committed
209 210 211

	/*
	 * Stupid gdb peeks/pokes the access registers in 64 bit with
212
	 * an alignment of 4. Programmers from hell...
Linus Torvalds's avatar
Linus Torvalds committed
213
	 */
214
	mask = __ADDR_MASK;
215
#ifdef CONFIG_64BIT
216 217 218 219 220
	if (addr >= (addr_t) &dummy->regs.acrs &&
	    addr < (addr_t) &dummy->regs.orig_gpr2)
		mask = 3;
#endif
	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
Linus Torvalds's avatar
Linus Torvalds committed
221 222
		return -EIO;

223 224 225 226 227 228 229 230 231 232 233 234 235 236 237
	tmp = __peek_user(child, addr);
	return put_user(tmp, (addr_t __user *) data);
}

/*
 * Write a word to the user area of a process at location addr. This
 * operation does have an additional problem compared to peek_user.
 * Stores to the program status word and on the floating point
 * control register needs to get checked for validity.
 */
static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
{
	struct user *dummy = NULL;
	addr_t offset;

Linus Torvalds's avatar
Linus Torvalds committed
238 239 240 241 242
	if (addr < (addr_t) &dummy->regs.acrs) {
		/*
		 * psw and gprs are stored on the stack
		 */
		if (addr == (addr_t) &dummy->regs.psw.mask &&
243
#ifdef CONFIG_COMPAT
Gerald Schaefer's avatar
Gerald Schaefer committed
244
		    data != PSW_MASK_MERGE(psw_user32_bits, data) &&
Linus Torvalds's avatar
Linus Torvalds committed
245
#endif
Gerald Schaefer's avatar
Gerald Schaefer committed
246
		    data != PSW_MASK_MERGE(psw_user_bits, data))
Linus Torvalds's avatar
Linus Torvalds committed
247 248
			/* Invalid psw mask. */
			return -EINVAL;
249
#ifndef CONFIG_64BIT
Linus Torvalds's avatar
Linus Torvalds committed
250 251 252 253 254
		if (addr == (addr_t) &dummy->regs.psw.addr)
			/* I'd like to reject addresses without the
			   high order bit but older gdb's rely on it */
			data |= PSW_ADDR_AMODE;
#endif
Al Viro's avatar
Al Viro committed
255
		*(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
Linus Torvalds's avatar
Linus Torvalds committed
256 257 258 259 260 261

	} else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
		/*
		 * access registers are stored in the thread structure
		 */
		offset = addr - (addr_t) &dummy->regs.acrs;
262
#ifdef CONFIG_64BIT
263 264 265 266 267 268 269 270 271 272
		/*
		 * Very special case: old & broken 64 bit gdb writing
		 * to acrs[15] with a 64 bit value. Ignore the lower
		 * half of the value and write the upper 32 bit to
		 * acrs[15]. Sick...
		 */
		if (addr == (addr_t) &dummy->regs.acrs[15])
			child->thread.acrs[15] = (unsigned int) (data >> 32);
		else
#endif
Linus Torvalds's avatar
Linus Torvalds committed
273 274 275 276 277 278
		*(addr_t *)((addr_t) &child->thread.acrs + offset) = data;

	} else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
		/*
		 * orig_gpr2 is stored on the kernel stack
		 */
Al Viro's avatar
Al Viro committed
279
		task_pt_regs(child)->orig_gpr2 = data;
Linus Torvalds's avatar
Linus Torvalds committed
280

281 282 283 284 285 286 287
	} else if (addr < (addr_t) &dummy->regs.fp_regs) {
		/*
		 * prevent writes of padding hole between
		 * orig_gpr2 and fp_regs on s390.
		 */
		return 0;

Linus Torvalds's avatar
Linus Torvalds committed
288 289 290 291 292
	} else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
		/*
		 * floating point regs. are stored in the thread structure
		 */
		if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
293 294
		    (data & ~((unsigned long) FPC_VALID_MASK
			      << (BITS_PER_LONG - 32))) != 0)
Linus Torvalds's avatar
Linus Torvalds committed
295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311
			return -EINVAL;
		offset = addr - (addr_t) &dummy->regs.fp_regs;
		*(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;

	} else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
		/*
		 * per_info is found in the thread structure 
		 */
		offset = addr - (addr_t) &dummy->regs.per_info;
		*(addr_t *)((addr_t) &child->thread.per_info + offset) = data;

	}

	FixPerRegisters(child);
	return 0;
}

312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333
static int
poke_user(struct task_struct *child, addr_t addr, addr_t data)
{
	struct user *dummy = NULL;
	addr_t mask;

	/*
	 * Stupid gdb peeks/pokes the access registers in 64 bit with
	 * an alignment of 4. Programmers from hell indeed...
	 */
	mask = __ADDR_MASK;
#ifdef CONFIG_64BIT
	if (addr >= (addr_t) &dummy->regs.acrs &&
	    addr < (addr_t) &dummy->regs.orig_gpr2)
		mask = 3;
#endif
	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
		return -EIO;

	return __poke_user(child, addr, data);
}

Roland McGrath's avatar
Roland McGrath committed
334
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
Linus Torvalds's avatar
Linus Torvalds committed
335 336 337 338 339 340 341 342 343 344
{
	ptrace_area parea; 
	int copied, ret;

	switch (request) {
	case PTRACE_PEEKTEXT:
	case PTRACE_PEEKDATA:
		/* Remove high order bit from address (only for 31 bit). */
		addr &= PSW_ADDR_INSN;
		/* read word at location addr. */
345
		return generic_ptrace_peekdata(child, addr, data);
Linus Torvalds's avatar
Linus Torvalds committed
346 347 348 349 350 351 352 353 354 355

	case PTRACE_PEEKUSR:
		/* read the word at location addr in the USER area. */
		return peek_user(child, addr, data);

	case PTRACE_POKETEXT:
	case PTRACE_POKEDATA:
		/* Remove high order bit from address (only for 31 bit). */
		addr &= PSW_ADDR_INSN;
		/* write the word at location addr. */
356
		return generic_ptrace_pokedata(child, addr, data);
Linus Torvalds's avatar
Linus Torvalds committed
357 358 359 360 361 362 363

	case PTRACE_POKEUSR:
		/* write the word at location addr in the USER area */
		return poke_user(child, addr, data);

	case PTRACE_PEEKUSR_AREA:
	case PTRACE_POKEUSR_AREA:
364
		if (copy_from_user(&parea, (void __force __user *) addr,
Linus Torvalds's avatar
Linus Torvalds committed
365 366 367 368 369 370 371 372 373
							sizeof(parea)))
			return -EFAULT;
		addr = parea.kernel_addr;
		data = parea.process_addr;
		copied = 0;
		while (copied < parea.len) {
			if (request == PTRACE_PEEKUSR_AREA)
				ret = peek_user(child, addr, data);
			else {
374 375 376
				addr_t utmp;
				if (get_user(utmp,
					     (addr_t __force __user *) data))
Linus Torvalds's avatar
Linus Torvalds committed
377
					return -EFAULT;
378
				ret = poke_user(child, addr, utmp);
Linus Torvalds's avatar
Linus Torvalds committed
379 380 381 382 383 384 385 386 387 388 389 390
			}
			if (ret)
				return ret;
			addr += sizeof(unsigned long);
			data += sizeof(unsigned long);
			copied += sizeof(unsigned long);
		}
		return 0;
	}
	return ptrace_request(child, request, addr, data);
}

391
#ifdef CONFIG_COMPAT
Linus Torvalds's avatar
Linus Torvalds committed
392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408
/*
 * Now the fun part starts... a 31 bit program running in the
 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 * to handle, the difference to the 64 bit versions of the requests
 * is that the access is done in multiples of 4 byte instead of
 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 * is a 31 bit program too, the content of struct user can be
 * emulated. A 31 bit program peeking into the struct user of
 * a 64 bit program is a no-no.
 */

/*
 * Same as peek_user but for a 31 bit program.
 */
409
static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
Linus Torvalds's avatar
Linus Torvalds committed
410 411 412 413 414 415 416 417 418 419 420 421
{
	struct user32 *dummy32 = NULL;
	per_struct32 *dummy_per32 = NULL;
	addr_t offset;
	__u32 tmp;

	if (addr < (addr_t) &dummy32->regs.acrs) {
		/*
		 * psw and gprs are stored on the stack
		 */
		if (addr == (addr_t) &dummy32->regs.psw.mask) {
			/* Fake a 31 bit psw mask. */
Al Viro's avatar
Al Viro committed
422
			tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
Gerald Schaefer's avatar
Gerald Schaefer committed
423
			tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
Linus Torvalds's avatar
Linus Torvalds committed
424 425
		} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
			/* Fake a 31 bit psw address. */
Al Viro's avatar
Al Viro committed
426
			tmp = (__u32) task_pt_regs(child)->psw.addr |
Linus Torvalds's avatar
Linus Torvalds committed
427 428 429
				PSW32_ADDR_AMODE31;
		} else {
			/* gpr 0-15 */
Al Viro's avatar
Al Viro committed
430
			tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw +
Linus Torvalds's avatar
Linus Torvalds committed
431 432 433 434 435 436 437 438 439 440 441 442 443
					 addr*2 + 4);
		}
	} else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
		/*
		 * access registers are stored in the thread structure
		 */
		offset = addr - (addr_t) &dummy32->regs.acrs;
		tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);

	} else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
		/*
		 * orig_gpr2 is stored on the kernel stack
		 */
Al Viro's avatar
Al Viro committed
444
		tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
Linus Torvalds's avatar
Linus Torvalds committed
445

446 447 448 449 450 451 452
	} else if (addr < (addr_t) &dummy32->regs.fp_regs) {
		/*
		 * prevent reads of padding hole between
		 * orig_gpr2 and fp_regs on s390.
		 */
		tmp = 0;

Linus Torvalds's avatar
Linus Torvalds committed
453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478
	} else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
		/*
		 * floating point regs. are stored in the thread structure 
		 */
	        offset = addr - (addr_t) &dummy32->regs.fp_regs;
		tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);

	} else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
		/*
		 * per_info is found in the thread structure
		 */
		offset = addr - (addr_t) &dummy32->regs.per_info;
		/* This is magic. See per_struct and per_struct32. */
		if ((offset >= (addr_t) &dummy_per32->control_regs &&
		     offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
		    (offset >= (addr_t) &dummy_per32->starting_addr &&
		     offset <= (addr_t) &dummy_per32->ending_addr) ||
		    offset == (addr_t) &dummy_per32->lowcore.words.address)
			offset = offset*2 + 4;
		else
			offset = offset*2;
		tmp = *(__u32 *)((addr_t) &child->thread.per_info + offset);

	} else
		tmp = 0;

479 480 481 482 483 484 485 486 487 488 489 490 491
	return tmp;
}

static int peek_user_compat(struct task_struct *child,
			    addr_t addr, addr_t data)
{
	__u32 tmp;

	if (!test_thread_flag(TIF_31BIT) ||
	    (addr & 3) || addr > sizeof(struct user) - 3)
		return -EIO;

	tmp = __peek_user_compat(child, addr);
Linus Torvalds's avatar
Linus Torvalds committed
492 493 494 495 496 497
	return put_user(tmp, (__u32 __user *) data);
}

/*
 * Same as poke_user but for a 31 bit program.
 */
498 499
static int __poke_user_compat(struct task_struct *child,
			      addr_t addr, addr_t data)
Linus Torvalds's avatar
Linus Torvalds committed
500 501 502
{
	struct user32 *dummy32 = NULL;
	per_struct32 *dummy_per32 = NULL;
503
	__u32 tmp = (__u32) data;
Linus Torvalds's avatar
Linus Torvalds committed
504 505 506 507 508 509 510 511
	addr_t offset;

	if (addr < (addr_t) &dummy32->regs.acrs) {
		/*
		 * psw, gprs, acrs and orig_gpr2 are stored on the stack
		 */
		if (addr == (addr_t) &dummy32->regs.psw.mask) {
			/* Build a 64 bit psw mask from 31 bit mask. */
Gerald Schaefer's avatar
Gerald Schaefer committed
512
			if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
Linus Torvalds's avatar
Linus Torvalds committed
513 514
				/* Invalid psw mask. */
				return -EINVAL;
Al Viro's avatar
Al Viro committed
515
			task_pt_regs(child)->psw.mask =
Gerald Schaefer's avatar
Gerald Schaefer committed
516
				PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
Linus Torvalds's avatar
Linus Torvalds committed
517 518
		} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
			/* Build a 64 bit psw address from 31 bit address. */
Al Viro's avatar
Al Viro committed
519
			task_pt_regs(child)->psw.addr =
Linus Torvalds's avatar
Linus Torvalds committed
520 521 522
				(__u64) tmp & PSW32_ADDR_INSN;
		} else {
			/* gpr 0-15 */
Al Viro's avatar
Al Viro committed
523
			*(__u32*)((addr_t) &task_pt_regs(child)->psw
Linus Torvalds's avatar
Linus Torvalds committed
524 525 526 527 528 529 530 531 532 533 534 535 536
				  + addr*2 + 4) = tmp;
		}
	} else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
		/*
		 * access registers are stored in the thread structure
		 */
		offset = addr - (addr_t) &dummy32->regs.acrs;
		*(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;

	} else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
		/*
		 * orig_gpr2 is stored on the kernel stack
		 */
Al Viro's avatar
Al Viro committed
537
		*(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
Linus Torvalds's avatar
Linus Torvalds committed
538

539 540 541 542 543 544 545
	} else if (addr < (addr_t) &dummy32->regs.fp_regs) {
		/*
		 * prevent writess of padding hole between
		 * orig_gpr2 and fp_regs on s390.
		 */
		return 0;

Linus Torvalds's avatar
Linus Torvalds committed
546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585
	} else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
		/*
		 * floating point regs. are stored in the thread structure 
		 */
		if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
		    (tmp & ~FPC_VALID_MASK) != 0)
			/* Invalid floating point control. */
			return -EINVAL;
	        offset = addr - (addr_t) &dummy32->regs.fp_regs;
		*(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;

	} else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
		/*
		 * per_info is found in the thread structure.
		 */
		offset = addr - (addr_t) &dummy32->regs.per_info;
		/*
		 * This is magic. See per_struct and per_struct32.
		 * By incident the offsets in per_struct are exactly
		 * twice the offsets in per_struct32 for all fields.
		 * The 8 byte fields need special handling though,
		 * because the second half (bytes 4-7) is needed and
		 * not the first half.
		 */
		if ((offset >= (addr_t) &dummy_per32->control_regs &&
		     offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
		    (offset >= (addr_t) &dummy_per32->starting_addr &&
		     offset <= (addr_t) &dummy_per32->ending_addr) ||
		    offset == (addr_t) &dummy_per32->lowcore.words.address)
			offset = offset*2 + 4;
		else
			offset = offset*2;
		*(__u32 *)((addr_t) &child->thread.per_info + offset) = tmp;

	}

	FixPerRegisters(child);
	return 0;
}

586 587 588 589 590 591 592 593 594 595
static int poke_user_compat(struct task_struct *child,
			    addr_t addr, addr_t data)
{
	if (!test_thread_flag(TIF_31BIT) ||
	    (addr & 3) || addr > sizeof(struct user32) - 3)
		return -EIO;

	return __poke_user_compat(child, addr, data);
}

Roland McGrath's avatar
Roland McGrath committed
596 597
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
			compat_ulong_t caddr, compat_ulong_t cdata)
Linus Torvalds's avatar
Linus Torvalds committed
598
{
Roland McGrath's avatar
Roland McGrath committed
599 600
	unsigned long addr = caddr;
	unsigned long data = cdata;
Linus Torvalds's avatar
Linus Torvalds committed
601 602 603 604 605 606
	ptrace_area_emu31 parea; 
	int copied, ret;

	switch (request) {
	case PTRACE_PEEKUSR:
		/* read the word at location addr in the USER area. */
607
		return peek_user_compat(child, addr, data);
Linus Torvalds's avatar
Linus Torvalds committed
608 609 610

	case PTRACE_POKEUSR:
		/* write the word at location addr in the USER area */
611
		return poke_user_compat(child, addr, data);
Linus Torvalds's avatar
Linus Torvalds committed
612 613 614

	case PTRACE_PEEKUSR_AREA:
	case PTRACE_POKEUSR_AREA:
615
		if (copy_from_user(&parea, (void __force __user *) addr,
Linus Torvalds's avatar
Linus Torvalds committed
616 617 618 619 620 621 622
							sizeof(parea)))
			return -EFAULT;
		addr = parea.kernel_addr;
		data = parea.process_addr;
		copied = 0;
		while (copied < parea.len) {
			if (request == PTRACE_PEEKUSR_AREA)
623
				ret = peek_user_compat(child, addr, data);
Linus Torvalds's avatar
Linus Torvalds committed
624
			else {
625 626 627
				__u32 utmp;
				if (get_user(utmp,
					     (__u32 __force __user *) data))
Linus Torvalds's avatar
Linus Torvalds committed
628
					return -EFAULT;
629
				ret = poke_user_compat(child, addr, utmp);
Linus Torvalds's avatar
Linus Torvalds committed
630 631 632 633 634 635 636 637 638
			}
			if (ret)
				return ret;
			addr += sizeof(unsigned int);
			data += sizeof(unsigned int);
			copied += sizeof(unsigned int);
		}
		return 0;
	}
Roland McGrath's avatar
Roland McGrath committed
639
	return compat_ptrace_request(child, request, addr, data);
Linus Torvalds's avatar
Linus Torvalds committed
640 641 642
}
#endif

Martin Schwidefsky's avatar
Martin Schwidefsky committed
643
asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
Linus Torvalds's avatar
Linus Torvalds committed
644
{
Martin Schwidefsky's avatar
Martin Schwidefsky committed
645
	long ret;
Linus Torvalds's avatar
Linus Torvalds committed
646

647
	/*
Martin Schwidefsky's avatar
Martin Schwidefsky committed
648 649
	 * The sysc_tracesys code in entry.S stored the system
	 * call number to gprs[2].
650
	 */
Martin Schwidefsky's avatar
Martin Schwidefsky committed
651 652 653 654 655 656 657 658 659
	ret = regs->gprs[2];
	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
	    (tracehook_report_syscall_entry(regs) ||
	     regs->gprs[2] >= NR_syscalls)) {
		/*
		 * Tracing decided this syscall should not happen or the
		 * debugger stored an invalid system call number. Skip
		 * the system call and the system call restart handling.
		 */
660
		regs->trap = -1;
Martin Schwidefsky's avatar
Martin Schwidefsky committed
661
		ret = -1;
Linus Torvalds's avatar
Linus Torvalds committed
662
	}
Martin Schwidefsky's avatar
Martin Schwidefsky committed
663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680

	if (unlikely(current->audit_context))
		audit_syscall_entry(test_thread_flag(TIF_31BIT) ?
					AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
				    regs->gprs[2], regs->orig_gpr2,
				    regs->gprs[3], regs->gprs[4],
				    regs->gprs[5]);
	return ret;
}

asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
{
	if (unlikely(current->audit_context))
		audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
				   regs->gprs[2]);

	if (test_thread_flag(TIF_SYSCALL_TRACE))
		tracehook_report_syscall_exit(regs, 0);
Linus Torvalds's avatar
Linus Torvalds committed
681
}
682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918

/*
 * user_regset definitions.
 */

static int s390_regs_get(struct task_struct *target,
			 const struct user_regset *regset,
			 unsigned int pos, unsigned int count,
			 void *kbuf, void __user *ubuf)
{
	if (target == current)
		save_access_regs(target->thread.acrs);

	if (kbuf) {
		unsigned long *k = kbuf;
		while (count > 0) {
			*k++ = __peek_user(target, pos);
			count -= sizeof(*k);
			pos += sizeof(*k);
		}
	} else {
		unsigned long __user *u = ubuf;
		while (count > 0) {
			if (__put_user(__peek_user(target, pos), u++))
				return -EFAULT;
			count -= sizeof(*u);
			pos += sizeof(*u);
		}
	}
	return 0;
}

static int s390_regs_set(struct task_struct *target,
			 const struct user_regset *regset,
			 unsigned int pos, unsigned int count,
			 const void *kbuf, const void __user *ubuf)
{
	int rc = 0;

	if (target == current)
		save_access_regs(target->thread.acrs);

	if (kbuf) {
		const unsigned long *k = kbuf;
		while (count > 0 && !rc) {
			rc = __poke_user(target, pos, *k++);
			count -= sizeof(*k);
			pos += sizeof(*k);
		}
	} else {
		const unsigned long  __user *u = ubuf;
		while (count > 0 && !rc) {
			unsigned long word;
			rc = __get_user(word, u++);
			if (rc)
				break;
			rc = __poke_user(target, pos, word);
			count -= sizeof(*u);
			pos += sizeof(*u);
		}
	}

	if (rc == 0 && target == current)
		restore_access_regs(target->thread.acrs);

	return rc;
}

static int s390_fpregs_get(struct task_struct *target,
			   const struct user_regset *regset, unsigned int pos,
			   unsigned int count, void *kbuf, void __user *ubuf)
{
	if (target == current)
		save_fp_regs(&target->thread.fp_regs);

	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
				   &target->thread.fp_regs, 0, -1);
}

static int s390_fpregs_set(struct task_struct *target,
			   const struct user_regset *regset, unsigned int pos,
			   unsigned int count, const void *kbuf,
			   const void __user *ubuf)
{
	int rc = 0;

	if (target == current)
		save_fp_regs(&target->thread.fp_regs);

	/* If setting FPC, must validate it first. */
	if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
		u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
					0, offsetof(s390_fp_regs, fprs));
		if (rc)
			return rc;
		if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
			return -EINVAL;
		target->thread.fp_regs.fpc = fpc[0];
	}

	if (rc == 0 && count > 0)
		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
					target->thread.fp_regs.fprs,
					offsetof(s390_fp_regs, fprs), -1);

	if (rc == 0 && target == current)
		restore_fp_regs(&target->thread.fp_regs);

	return rc;
}

static const struct user_regset s390_regsets[] = {
	[REGSET_GENERAL] = {
		.core_note_type = NT_PRSTATUS,
		.n = sizeof(s390_regs) / sizeof(long),
		.size = sizeof(long),
		.align = sizeof(long),
		.get = s390_regs_get,
		.set = s390_regs_set,
	},
	[REGSET_FP] = {
		.core_note_type = NT_PRFPREG,
		.n = sizeof(s390_fp_regs) / sizeof(long),
		.size = sizeof(long),
		.align = sizeof(long),
		.get = s390_fpregs_get,
		.set = s390_fpregs_set,
	},
};

static const struct user_regset_view user_s390_view = {
	.name = UTS_MACHINE,
	.e_machine = EM_S390,
	.regsets = s390_regsets,
	.n = ARRAY_SIZE(s390_regsets)
};

#ifdef CONFIG_COMPAT
static int s390_compat_regs_get(struct task_struct *target,
				const struct user_regset *regset,
				unsigned int pos, unsigned int count,
				void *kbuf, void __user *ubuf)
{
	if (target == current)
		save_access_regs(target->thread.acrs);

	if (kbuf) {
		compat_ulong_t *k = kbuf;
		while (count > 0) {
			*k++ = __peek_user_compat(target, pos);
			count -= sizeof(*k);
			pos += sizeof(*k);
		}
	} else {
		compat_ulong_t __user *u = ubuf;
		while (count > 0) {
			if (__put_user(__peek_user_compat(target, pos), u++))
				return -EFAULT;
			count -= sizeof(*u);
			pos += sizeof(*u);
		}
	}
	return 0;
}

static int s390_compat_regs_set(struct task_struct *target,
				const struct user_regset *regset,
				unsigned int pos, unsigned int count,
				const void *kbuf, const void __user *ubuf)
{
	int rc = 0;

	if (target == current)
		save_access_regs(target->thread.acrs);

	if (kbuf) {
		const compat_ulong_t *k = kbuf;
		while (count > 0 && !rc) {
			rc = __poke_user_compat(target, pos, *k++);
			count -= sizeof(*k);
			pos += sizeof(*k);
		}
	} else {
		const compat_ulong_t  __user *u = ubuf;
		while (count > 0 && !rc) {
			compat_ulong_t word;
			rc = __get_user(word, u++);
			if (rc)
				break;
			rc = __poke_user_compat(target, pos, word);
			count -= sizeof(*u);
			pos += sizeof(*u);
		}
	}

	if (rc == 0 && target == current)
		restore_access_regs(target->thread.acrs);

	return rc;
}

static const struct user_regset s390_compat_regsets[] = {
	[REGSET_GENERAL] = {
		.core_note_type = NT_PRSTATUS,
		.n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
		.size = sizeof(compat_long_t),
		.align = sizeof(compat_long_t),
		.get = s390_compat_regs_get,
		.set = s390_compat_regs_set,
	},
	[REGSET_FP] = {
		.core_note_type = NT_PRFPREG,
		.n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
		.size = sizeof(compat_long_t),
		.align = sizeof(compat_long_t),
		.get = s390_fpregs_get,
		.set = s390_fpregs_set,
	},
};

static const struct user_regset_view user_s390_compat_view = {
	.name = "s390",
	.e_machine = EM_S390,
	.regsets = s390_compat_regsets,
	.n = ARRAY_SIZE(s390_compat_regsets)
};
#endif

const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
#ifdef CONFIG_COMPAT
	if (test_tsk_thread_flag(task, TIF_31BIT))
		return &user_s390_compat_view;
#endif
	return &user_s390_view;
}