1/* By Ross Biro 1/23/92 */
   2/*
   3 * Pentium III FXSR, SSE support
   4 *	Gareth Hughes <gareth@valinux.com>, May 2000
   5 */
   6
   7#include <linux/kernel.h>
   8#include <linux/sched.h>
   9#include <linux/mm.h>
  10#include <linux/smp.h>
  11#include <linux/errno.h>
  12#include <linux/slab.h>
  13#include <linux/ptrace.h>
  14#include <linux/regset.h>
  15#include <linux/tracehook.h>
  16#include <linux/user.h>
  17#include <linux/elf.h>
  18#include <linux/security.h>
  19#include <linux/audit.h>
  20#include <linux/seccomp.h>
  21#include <linux/signal.h>
  22#include <linux/perf_event.h>
  23#include <linux/hw_breakpoint.h>
  24
  25#include <asm/uaccess.h>
  26#include <asm/pgtable.h>
 
  27#include <asm/processor.h>
  28#include <asm/i387.h>
  29#include <asm/fpu-internal.h>
  30#include <asm/debugreg.h>
  31#include <asm/ldt.h>
  32#include <asm/desc.h>
  33#include <asm/prctl.h>
  34#include <asm/proto.h>
  35#include <asm/hw_breakpoint.h>
  36#include <asm/traps.h>
  37
  38#include "tls.h"
  39
  40#define CREATE_TRACE_POINTS
  41#include <trace/events/syscalls.h>
  42
  43enum x86_regset {
  44	REGSET_GENERAL,
  45	REGSET_FP,
  46	REGSET_XFP,
  47	REGSET_IOPERM64 = REGSET_XFP,
  48	REGSET_XSTATE,
  49	REGSET_TLS,
  50	REGSET_IOPERM32,
  51};
  52
  53struct pt_regs_offset {
  54	const char *name;
  55	int offset;
  56};
  57
  58#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
  59#define REG_OFFSET_END {.name = NULL, .offset = 0}
  60
  61static const struct pt_regs_offset regoffset_table[] = {
  62#ifdef CONFIG_X86_64
  63	REG_OFFSET_NAME(r15),
  64	REG_OFFSET_NAME(r14),
  65	REG_OFFSET_NAME(r13),
  66	REG_OFFSET_NAME(r12),
  67	REG_OFFSET_NAME(r11),
  68	REG_OFFSET_NAME(r10),
  69	REG_OFFSET_NAME(r9),
  70	REG_OFFSET_NAME(r8),
  71#endif
  72	REG_OFFSET_NAME(bx),
  73	REG_OFFSET_NAME(cx),
  74	REG_OFFSET_NAME(dx),
  75	REG_OFFSET_NAME(si),
  76	REG_OFFSET_NAME(di),
  77	REG_OFFSET_NAME(bp),
  78	REG_OFFSET_NAME(ax),
  79#ifdef CONFIG_X86_32
  80	REG_OFFSET_NAME(ds),
  81	REG_OFFSET_NAME(es),
  82	REG_OFFSET_NAME(fs),
  83	REG_OFFSET_NAME(gs),
  84#endif
  85	REG_OFFSET_NAME(orig_ax),
  86	REG_OFFSET_NAME(ip),
  87	REG_OFFSET_NAME(cs),
  88	REG_OFFSET_NAME(flags),
  89	REG_OFFSET_NAME(sp),
  90	REG_OFFSET_NAME(ss),
  91	REG_OFFSET_END,
  92};
  93
  94/**
  95 * regs_query_register_offset() - query register offset from its name
  96 * @name:	the name of a register
  97 *
  98 * regs_query_register_offset() returns the offset of a register in struct
  99 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 100 */
 101int regs_query_register_offset(const char *name)
 102{
 103	const struct pt_regs_offset *roff;
 104	for (roff = regoffset_table; roff->name != NULL; roff++)
 105		if (!strcmp(roff->name, name))
 106			return roff->offset;
 107	return -EINVAL;
 108}
 109
 110/**
 111 * regs_query_register_name() - query register name from its offset
 112 * @offset:	the offset of a register in struct pt_regs.
 113 *
 114 * regs_query_register_name() returns the name of a register from its
 115 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
 116 */
 117const char *regs_query_register_name(unsigned int offset)
 118{
 119	const struct pt_regs_offset *roff;
 120	for (roff = regoffset_table; roff->name != NULL; roff++)
 121		if (roff->offset == offset)
 122			return roff->name;
 123	return NULL;
 124}
 125
 126static const int arg_offs_table[] = {
 127#ifdef CONFIG_X86_32
 128	[0] = offsetof(struct pt_regs, ax),
 129	[1] = offsetof(struct pt_regs, dx),
 130	[2] = offsetof(struct pt_regs, cx)
 131#else /* CONFIG_X86_64 */
 132	[0] = offsetof(struct pt_regs, di),
 133	[1] = offsetof(struct pt_regs, si),
 134	[2] = offsetof(struct pt_regs, dx),
 135	[3] = offsetof(struct pt_regs, cx),
 136	[4] = offsetof(struct pt_regs, r8),
 137	[5] = offsetof(struct pt_regs, r9)
 138#endif
 139};
 140
 141/*
 142 * does not yet catch signals sent when the child dies.
 143 * in exit.c or in signal.c.
 144 */
 145
 146/*
 147 * Determines which flags the user has access to [1 = access, 0 = no access].
 148 */
 149#define FLAG_MASK_32		((unsigned long)			\
 150				 (X86_EFLAGS_CF | X86_EFLAGS_PF |	\
 151				  X86_EFLAGS_AF | X86_EFLAGS_ZF |	\
 152				  X86_EFLAGS_SF | X86_EFLAGS_TF |	\
 153				  X86_EFLAGS_DF | X86_EFLAGS_OF |	\
 154				  X86_EFLAGS_RF | X86_EFLAGS_AC))
 155
 156/*
 157 * Determines whether a value may be installed in a segment register.
 158 */
 159static inline bool invalid_selector(u16 value)
 160{
 161	return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
 162}
 163
 164#ifdef CONFIG_X86_32
 165
 166#define FLAG_MASK		FLAG_MASK_32
 167
 168static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
 169{
 170	BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
 171	return &regs->bx + (regno >> 2);
 172}
 173
 174static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 175{
 176	/*
 177	 * Returning the value truncates it to 16 bits.
 178	 */
 179	unsigned int retval;
 180	if (offset != offsetof(struct user_regs_struct, gs))
 181		retval = *pt_regs_access(task_pt_regs(task), offset);
 182	else {
 183		if (task == current)
 184			retval = get_user_gs(task_pt_regs(task));
 185		else
 186			retval = task_user_gs(task);
 187	}
 188	return retval;
 189}
 190
 191static int set_segment_reg(struct task_struct *task,
 192			   unsigned long offset, u16 value)
 193{
 194	/*
 195	 * The value argument was already truncated to 16 bits.
 196	 */
 197	if (invalid_selector(value))
 198		return -EIO;
 199
 200	/*
 201	 * For %cs and %ss we cannot permit a null selector.
 202	 * We can permit a bogus selector as long as it has USER_RPL.
 203	 * Null selectors are fine for other segment registers, but
 204	 * we will never get back to user mode with invalid %cs or %ss
 205	 * and will take the trap in iret instead.  Much code relies
 206	 * on user_mode() to distinguish a user trap frame (which can
 207	 * safely use invalid selectors) from a kernel trap frame.
 208	 */
 209	switch (offset) {
 210	case offsetof(struct user_regs_struct, cs):
 211	case offsetof(struct user_regs_struct, ss):
 212		if (unlikely(value == 0))
 213			return -EIO;
 214
 215	default:
 216		*pt_regs_access(task_pt_regs(task), offset) = value;
 217		break;
 218
 219	case offsetof(struct user_regs_struct, gs):
 220		if (task == current)
 221			set_user_gs(task_pt_regs(task), value);
 222		else
 223			task_user_gs(task) = value;
 224	}
 225
 226	return 0;
 227}
 228
 229#else  /* CONFIG_X86_64 */
 230
 231#define FLAG_MASK		(FLAG_MASK_32 | X86_EFLAGS_NT)
 232
 233static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
 234{
 235	BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
 236	return &regs->r15 + (offset / sizeof(regs->r15));
 237}
 238
 239static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 240{
 241	/*
 242	 * Returning the value truncates it to 16 bits.
 243	 */
 244	unsigned int seg;
 245
 246	switch (offset) {
 247	case offsetof(struct user_regs_struct, fs):
 248		if (task == current) {
 249			/* Older gas can't assemble movq %?s,%r?? */
 250			asm("movl %%fs,%0" : "=r" (seg));
 251			return seg;
 252		}
 253		return task->thread.fsindex;
 254	case offsetof(struct user_regs_struct, gs):
 255		if (task == current) {
 256			asm("movl %%gs,%0" : "=r" (seg));
 257			return seg;
 258		}
 259		return task->thread.gsindex;
 260	case offsetof(struct user_regs_struct, ds):
 261		if (task == current) {
 262			asm("movl %%ds,%0" : "=r" (seg));
 263			return seg;
 264		}
 265		return task->thread.ds;
 266	case offsetof(struct user_regs_struct, es):
 267		if (task == current) {
 268			asm("movl %%es,%0" : "=r" (seg));
 269			return seg;
 270		}
 271		return task->thread.es;
 272
 273	case offsetof(struct user_regs_struct, cs):
 274	case offsetof(struct user_regs_struct, ss):
 275		break;
 276	}
 277	return *pt_regs_access(task_pt_regs(task), offset);
 278}
 279
 280static int set_segment_reg(struct task_struct *task,
 281			   unsigned long offset, u16 value)
 282{
 283	/*
 284	 * The value argument was already truncated to 16 bits.
 285	 */
 286	if (invalid_selector(value))
 287		return -EIO;
 288
 289	switch (offset) {
 290	case offsetof(struct user_regs_struct,fs):
 291		/*
 292		 * If this is setting fs as for normal 64-bit use but
 293		 * setting fs_base has implicitly changed it, leave it.
 294		 */
 295		if ((value == FS_TLS_SEL && task->thread.fsindex == 0 &&
 296		     task->thread.fs != 0) ||
 297		    (value == 0 && task->thread.fsindex == FS_TLS_SEL &&
 298		     task->thread.fs == 0))
 299			break;
 300		task->thread.fsindex = value;
 301		if (task == current)
 302			loadsegment(fs, task->thread.fsindex);
 303		break;
 304	case offsetof(struct user_regs_struct,gs):
 305		/*
 306		 * If this is setting gs as for normal 64-bit use but
 307		 * setting gs_base has implicitly changed it, leave it.
 308		 */
 309		if ((value == GS_TLS_SEL && task->thread.gsindex == 0 &&
 310		     task->thread.gs != 0) ||
 311		    (value == 0 && task->thread.gsindex == GS_TLS_SEL &&
 312		     task->thread.gs == 0))
 313			break;
 314		task->thread.gsindex = value;
 315		if (task == current)
 316			load_gs_index(task->thread.gsindex);
 317		break;
 318	case offsetof(struct user_regs_struct,ds):
 319		task->thread.ds = value;
 320		if (task == current)
 321			loadsegment(ds, task->thread.ds);
 322		break;
 323	case offsetof(struct user_regs_struct,es):
 324		task->thread.es = value;
 325		if (task == current)
 326			loadsegment(es, task->thread.es);
 327		break;
 328
 329		/*
 330		 * Can't actually change these in 64-bit mode.
 331		 */
 332	case offsetof(struct user_regs_struct,cs):
 333		if (unlikely(value == 0))
 334			return -EIO;
 335#ifdef CONFIG_IA32_EMULATION
 336		if (test_tsk_thread_flag(task, TIF_IA32))
 337			task_pt_regs(task)->cs = value;
 338#endif
 339		break;
 340	case offsetof(struct user_regs_struct,ss):
 341		if (unlikely(value == 0))
 342			return -EIO;
 343#ifdef CONFIG_IA32_EMULATION
 344		if (test_tsk_thread_flag(task, TIF_IA32))
 345			task_pt_regs(task)->ss = value;
 346#endif
 347		break;
 348	}
 349
 350	return 0;
 351}
 352
 353#endif	/* CONFIG_X86_32 */
 354
 355static unsigned long get_flags(struct task_struct *task)
 356{
 357	unsigned long retval = task_pt_regs(task)->flags;
 358
 359	/*
 360	 * If the debugger set TF, hide it from the readout.
 361	 */
 362	if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 363		retval &= ~X86_EFLAGS_TF;
 364
 365	return retval;
 366}
 367
 368static int set_flags(struct task_struct *task, unsigned long value)
 369{
 370	struct pt_regs *regs = task_pt_regs(task);
 371
 372	/*
 373	 * If the user value contains TF, mark that
 374	 * it was not "us" (the debugger) that set it.
 375	 * If not, make sure it stays set if we had.
 376	 */
 377	if (value & X86_EFLAGS_TF)
 378		clear_tsk_thread_flag(task, TIF_FORCED_TF);
 379	else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 380		value |= X86_EFLAGS_TF;
 381
 382	regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
 383
 384	return 0;
 385}
 386
 387static int putreg(struct task_struct *child,
 388		  unsigned long offset, unsigned long value)
 389{
 390	switch (offset) {
 391	case offsetof(struct user_regs_struct, cs):
 392	case offsetof(struct user_regs_struct, ds):
 393	case offsetof(struct user_regs_struct, es):
 394	case offsetof(struct user_regs_struct, fs):
 395	case offsetof(struct user_regs_struct, gs):
 396	case offsetof(struct user_regs_struct, ss):
 397		return set_segment_reg(child, offset, value);
 398
 399	case offsetof(struct user_regs_struct, flags):
 400		return set_flags(child, value);
 401
 402#ifdef CONFIG_X86_64
 403	case offsetof(struct user_regs_struct,fs_base):
 404		if (value >= TASK_SIZE_OF(child))
 405			return -EIO;
 406		/*
 407		 * When changing the segment base, use do_arch_prctl
 408		 * to set either thread.fs or thread.fsindex and the
 409		 * corresponding GDT slot.
 410		 */
 411		if (child->thread.fs != value)
 412			return do_arch_prctl(child, ARCH_SET_FS, value);
 413		return 0;
 414	case offsetof(struct user_regs_struct,gs_base):
 415		/*
 416		 * Exactly the same here as the %fs handling above.
 417		 */
 418		if (value >= TASK_SIZE_OF(child))
 419			return -EIO;
 420		if (child->thread.gs != value)
 421			return do_arch_prctl(child, ARCH_SET_GS, value);
 422		return 0;
 423#endif
 424	}
 425
 426	*pt_regs_access(task_pt_regs(child), offset) = value;
 427	return 0;
 428}
 429
 430static unsigned long getreg(struct task_struct *task, unsigned long offset)
 431{
 432	switch (offset) {
 433	case offsetof(struct user_regs_struct, cs):
 434	case offsetof(struct user_regs_struct, ds):
 435	case offsetof(struct user_regs_struct, es):
 436	case offsetof(struct user_regs_struct, fs):
 437	case offsetof(struct user_regs_struct, gs):
 438	case offsetof(struct user_regs_struct, ss):
 439		return get_segment_reg(task, offset);
 440
 441	case offsetof(struct user_regs_struct, flags):
 442		return get_flags(task);
 443
 444#ifdef CONFIG_X86_64
 445	case offsetof(struct user_regs_struct, fs_base): {
 446		/*
 447		 * do_arch_prctl may have used a GDT slot instead of
 448		 * the MSR.  To userland, it appears the same either
 449		 * way, except the %fs segment selector might not be 0.
 450		 */
 451		unsigned int seg = task->thread.fsindex;
 452		if (task->thread.fs != 0)
 453			return task->thread.fs;
 454		if (task == current)
 455			asm("movl %%fs,%0" : "=r" (seg));
 456		if (seg != FS_TLS_SEL)
 457			return 0;
 458		return get_desc_base(&task->thread.tls_array[FS_TLS]);
 459	}
 460	case offsetof(struct user_regs_struct, gs_base): {
 461		/*
 462		 * Exactly the same here as the %fs handling above.
 463		 */
 464		unsigned int seg = task->thread.gsindex;
 465		if (task->thread.gs != 0)
 466			return task->thread.gs;
 467		if (task == current)
 468			asm("movl %%gs,%0" : "=r" (seg));
 469		if (seg != GS_TLS_SEL)
 470			return 0;
 471		return get_desc_base(&task->thread.tls_array[GS_TLS]);
 472	}
 473#endif
 474	}
 475
 476	return *pt_regs_access(task_pt_regs(task), offset);
 477}
 478
 479static int genregs_get(struct task_struct *target,
 480		       const struct user_regset *regset,
 481		       unsigned int pos, unsigned int count,
 482		       void *kbuf, void __user *ubuf)
 483{
 484	if (kbuf) {
 485		unsigned long *k = kbuf;
 486		while (count >= sizeof(*k)) {
 487			*k++ = getreg(target, pos);
 488			count -= sizeof(*k);
 489			pos += sizeof(*k);
 490		}
 491	} else {
 492		unsigned long __user *u = ubuf;
 493		while (count >= sizeof(*u)) {
 494			if (__put_user(getreg(target, pos), u++))
 495				return -EFAULT;
 496			count -= sizeof(*u);
 497			pos += sizeof(*u);
 498		}
 499	}
 500
 501	return 0;
 502}
 503
 504static int genregs_set(struct task_struct *target,
 505		       const struct user_regset *regset,
 506		       unsigned int pos, unsigned int count,
 507		       const void *kbuf, const void __user *ubuf)
 508{
 509	int ret = 0;
 510	if (kbuf) {
 511		const unsigned long *k = kbuf;
 512		while (count >= sizeof(*k) && !ret) {
 513			ret = putreg(target, pos, *k++);
 514			count -= sizeof(*k);
 515			pos += sizeof(*k);
 516		}
 517	} else {
 518		const unsigned long  __user *u = ubuf;
 519		while (count >= sizeof(*u) && !ret) {
 520			unsigned long word;
 521			ret = __get_user(word, u++);
 522			if (ret)
 523				break;
 524			ret = putreg(target, pos, word);
 525			count -= sizeof(*u);
 526			pos += sizeof(*u);
 527		}
 528	}
 529	return ret;
 530}
 531
 532static void ptrace_triggered(struct perf_event *bp,
 533			     struct perf_sample_data *data,
 534			     struct pt_regs *regs)
 535{
 536	int i;
 537	struct thread_struct *thread = &(current->thread);
 538
 539	/*
 540	 * Store in the virtual DR6 register the fact that the breakpoint
 541	 * was hit so the thread's debugger will see it.
 542	 */
 543	for (i = 0; i < HBP_NUM; i++) {
 544		if (thread->ptrace_bps[i] == bp)
 545			break;
 546	}
 547
 548	thread->debugreg6 |= (DR_TRAP0 << i);
 549}
 550
 551/*
 552 * Walk through every ptrace breakpoints for this thread and
 553 * build the dr7 value on top of their attributes.
 554 *
 555 */
 556static unsigned long ptrace_get_dr7(struct perf_event *bp[])
 557{
 558	int i;
 559	int dr7 = 0;
 560	struct arch_hw_breakpoint *info;
 561
 562	for (i = 0; i < HBP_NUM; i++) {
 563		if (bp[i] && !bp[i]->attr.disabled) {
 564			info = counter_arch_bp(bp[i]);
 565			dr7 |= encode_dr7(i, info->len, info->type);
 566		}
 567	}
 568
 569	return dr7;
 570}
 571
 572static int
 573ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
 574			 struct task_struct *tsk, int disabled)
 575{
 576	int err;
 577	int gen_len, gen_type;
 578	struct perf_event_attr attr;
 579
 580	/*
 581	 * We should have at least an inactive breakpoint at this
 582	 * slot. It means the user is writing dr7 without having
 583	 * written the address register first
 584	 */
 585	if (!bp)
 586		return -EINVAL;
 587
 588	err = arch_bp_generic_fields(len, type, &gen_len, &gen_type);
 589	if (err)
 590		return err;
 591
 592	attr = bp->attr;
 593	attr.bp_len = gen_len;
 594	attr.bp_type = gen_type;
 595	attr.disabled = disabled;
 596
 597	return modify_user_hw_breakpoint(bp, &attr);
 598}
 599
 600/*
 601 * Handle ptrace writes to debug register 7.
 602 */
 603static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
 604{
 605	struct thread_struct *thread = &(tsk->thread);
 606	unsigned long old_dr7;
 607	int i, orig_ret = 0, rc = 0;
 608	int enabled, second_pass = 0;
 609	unsigned len, type;
 610	struct perf_event *bp;
 611
 612	if (ptrace_get_breakpoints(tsk) < 0)
 613		return -ESRCH;
 614
 615	data &= ~DR_CONTROL_RESERVED;
 616	old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
 617restore:
 618	/*
 619	 * Loop through all the hardware breakpoints, making the
 620	 * appropriate changes to each.
 621	 */
 622	for (i = 0; i < HBP_NUM; i++) {
 623		enabled = decode_dr7(data, i, &len, &type);
 624		bp = thread->ptrace_bps[i];
 625
 626		if (!enabled) {
 627			if (bp) {
 628				/*
 629				 * Don't unregister the breakpoints right-away,
 630				 * unless all register_user_hw_breakpoint()
 631				 * requests have succeeded. This prevents
 632				 * any window of opportunity for debug
 633				 * register grabbing by other users.
 634				 */
 635				if (!second_pass)
 636					continue;
 637
 638				rc = ptrace_modify_breakpoint(bp, len, type,
 639							      tsk, 1);
 640				if (rc)
 641					break;
 642			}
 643			continue;
 644		}
 645
 646		rc = ptrace_modify_breakpoint(bp, len, type, tsk, 0);
 647		if (rc)
 648			break;
 649	}
 650	/*
 651	 * Make a second pass to free the remaining unused breakpoints
 652	 * or to restore the original breakpoints if an error occurred.
 653	 */
 654	if (!second_pass) {
 655		second_pass = 1;
 656		if (rc < 0) {
 657			orig_ret = rc;
 658			data = old_dr7;
 659		}
 660		goto restore;
 661	}
 662
 663	ptrace_put_breakpoints(tsk);
 664
 665	return ((orig_ret < 0) ? orig_ret : rc);
 666}
 667
 668/*
 669 * Handle PTRACE_PEEKUSR calls for the debug register area.
 670 */
 671static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
 672{
 673	struct thread_struct *thread = &(tsk->thread);
 674	unsigned long val = 0;
 675
 676	if (n < HBP_NUM) {
 677		struct perf_event *bp;
 678
 679		if (ptrace_get_breakpoints(tsk) < 0)
 680			return -ESRCH;
 681
 682		bp = thread->ptrace_bps[n];
 683		if (!bp)
 684			val = 0;
 685		else
 686			val = bp->hw.info.address;
 687
 688		ptrace_put_breakpoints(tsk);
 689	} else if (n == 6) {
 690		val = thread->debugreg6;
 691	 } else if (n == 7) {
 692		val = thread->ptrace_dr7;
 693	}
 694	return val;
 695}
 696
 697static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
 698				      unsigned long addr)
 699{
 700	struct perf_event *bp;
 701	struct thread_struct *t = &tsk->thread;
 702	struct perf_event_attr attr;
 703	int err = 0;
 704
 705	if (ptrace_get_breakpoints(tsk) < 0)
 706		return -ESRCH;
 707
 708	if (!t->ptrace_bps[nr]) {
 709		ptrace_breakpoint_init(&attr);
 710		/*
 711		 * Put stub len and type to register (reserve) an inactive but
 712		 * correct bp
 713		 */
 714		attr.bp_addr = addr;
 715		attr.bp_len = HW_BREAKPOINT_LEN_1;
 716		attr.bp_type = HW_BREAKPOINT_W;
 717		attr.disabled = 1;
 718
 719		bp = register_user_hw_breakpoint(&attr, ptrace_triggered,
 720						 NULL, tsk);
 721
 722		/*
 723		 * CHECKME: the previous code returned -EIO if the addr wasn't
 724		 * a valid task virtual addr. The new one will return -EINVAL in
 725		 *  this case.
 726		 * -EINVAL may be what we want for in-kernel breakpoints users,
 727		 * but -EIO looks better for ptrace, since we refuse a register
 728		 * writing for the user. And anyway this is the previous
 729		 * behaviour.
 730		 */
 731		if (IS_ERR(bp)) {
 732			err = PTR_ERR(bp);
 733			goto put;
 734		}
 735
 736		t->ptrace_bps[nr] = bp;
 737	} else {
 738		bp = t->ptrace_bps[nr];
 739
 740		attr = bp->attr;
 741		attr.bp_addr = addr;
 742		err = modify_user_hw_breakpoint(bp, &attr);
 743	}
 744
 745put:
 746	ptrace_put_breakpoints(tsk);
 747	return err;
 748}
 749
 750/*
 751 * Handle PTRACE_POKEUSR calls for the debug register area.
 752 */
 753static int ptrace_set_debugreg(struct task_struct *tsk, int n,
 754			       unsigned long val)
 755{
 756	struct thread_struct *thread = &(tsk->thread);
 757	int rc = 0;
 758
 759	/* There are no DR4 or DR5 registers */
 760	if (n == 4 || n == 5)
 761		return -EIO;
 762
 763	if (n == 6) {
 764		thread->debugreg6 = val;
 765		goto ret_path;
 766	}
 767	if (n < HBP_NUM) {
 768		rc = ptrace_set_breakpoint_addr(tsk, n, val);
 769		if (rc)
 770			return rc;
 771	}
 772	/* All that's left is DR7 */
 773	if (n == 7) {
 774		rc = ptrace_write_dr7(tsk, val);
 775		if (!rc)
 776			thread->ptrace_dr7 = val;
 777	}
 778
 779ret_path:
 780	return rc;
 781}
 782
 783/*
 784 * These access the current or another (stopped) task's io permission
 785 * bitmap for debugging or core dump.
 786 */
 787static int ioperm_active(struct task_struct *target,
 788			 const struct user_regset *regset)
 789{
 790	return target->thread.io_bitmap_max / regset->size;
 791}
 792
 793static int ioperm_get(struct task_struct *target,
 794		      const struct user_regset *regset,
 795		      unsigned int pos, unsigned int count,
 796		      void *kbuf, void __user *ubuf)
 797{
 798	if (!target->thread.io_bitmap_ptr)
 799		return -ENXIO;
 800
 801	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 802				   target->thread.io_bitmap_ptr,
 803				   0, IO_BITMAP_BYTES);
 804}
 805
 806/*
 807 * Called by kernel/ptrace.c when detaching..
 808 *
 809 * Make sure the single step bit is not set.
 810 */
 811void ptrace_disable(struct task_struct *child)
 812{
 813	user_disable_single_step(child);
 814#ifdef TIF_SYSCALL_EMU
 815	clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 816#endif
 817}
 818
 819#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 820static const struct user_regset_view user_x86_32_view; /* Initialized below. */
 821#endif
 822
 823long arch_ptrace(struct task_struct *child, long request,
 824		 unsigned long addr, unsigned long data)
 825{
 826	int ret;
 827	unsigned long __user *datap = (unsigned long __user *)data;
 828
 829	switch (request) {
 830	/* read the word at location addr in the USER area. */
 831	case PTRACE_PEEKUSR: {
 832		unsigned long tmp;
 833
 834		ret = -EIO;
 835		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
 836			break;
 837
 838		tmp = 0;  /* Default return condition */
 839		if (addr < sizeof(struct user_regs_struct))
 840			tmp = getreg(child, addr);
 841		else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 842			 addr <= offsetof(struct user, u_debugreg[7])) {
 843			addr -= offsetof(struct user, u_debugreg[0]);
 844			tmp = ptrace_get_debugreg(child, addr / sizeof(data));
 845		}
 846		ret = put_user(tmp, datap);
 847		break;
 848	}
 849
 850	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 851		ret = -EIO;
 852		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
 853			break;
 854
 855		if (addr < sizeof(struct user_regs_struct))
 856			ret = putreg(child, addr, data);
 857		else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 858			 addr <= offsetof(struct user, u_debugreg[7])) {
 859			addr -= offsetof(struct user, u_debugreg[0]);
 860			ret = ptrace_set_debugreg(child,
 861						  addr / sizeof(data), data);
 862		}
 863		break;
 864
 865	case PTRACE_GETREGS:	/* Get all gp regs from the child. */
 866		return copy_regset_to_user(child,
 867					   task_user_regset_view(current),
 868					   REGSET_GENERAL,
 869					   0, sizeof(struct user_regs_struct),
 870					   datap);
 871
 872	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
 873		return copy_regset_from_user(child,
 874					     task_user_regset_view(current),
 875					     REGSET_GENERAL,
 876					     0, sizeof(struct user_regs_struct),
 877					     datap);
 878
 879	case PTRACE_GETFPREGS:	/* Get the child FPU state. */
 880		return copy_regset_to_user(child,
 881					   task_user_regset_view(current),
 882					   REGSET_FP,
 883					   0, sizeof(struct user_i387_struct),
 884					   datap);
 885
 886	case PTRACE_SETFPREGS:	/* Set the child FPU state. */
 887		return copy_regset_from_user(child,
 888					     task_user_regset_view(current),
 889					     REGSET_FP,
 890					     0, sizeof(struct user_i387_struct),
 891					     datap);
 892
 893#ifdef CONFIG_X86_32
 894	case PTRACE_GETFPXREGS:	/* Get the child extended FPU state. */
 895		return copy_regset_to_user(child, &user_x86_32_view,
 896					   REGSET_XFP,
 897					   0, sizeof(struct user_fxsr_struct),
 898					   datap) ? -EIO : 0;
 899
 900	case PTRACE_SETFPXREGS:	/* Set the child extended FPU state. */
 901		return copy_regset_from_user(child, &user_x86_32_view,
 902					     REGSET_XFP,
 903					     0, sizeof(struct user_fxsr_struct),
 904					     datap) ? -EIO : 0;
 905#endif
 906
 907#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 908	case PTRACE_GET_THREAD_AREA:
 909		if ((int) addr < 0)
 910			return -EIO;
 911		ret = do_get_thread_area(child, addr,
 912					(struct user_desc __user *)data);
 913		break;
 914
 915	case PTRACE_SET_THREAD_AREA:
 916		if ((int) addr < 0)
 917			return -EIO;
 918		ret = do_set_thread_area(child, addr,
 919					(struct user_desc __user *)data, 0);
 920		break;
 921#endif
 922
 923#ifdef CONFIG_X86_64
 924		/* normal 64bit interface to access TLS data.
 925		   Works just like arch_prctl, except that the arguments
 926		   are reversed. */
 927	case PTRACE_ARCH_PRCTL:
 928		ret = do_arch_prctl(child, data, addr);
 929		break;
 930#endif
 931
 932	default:
 933		ret = ptrace_request(child, request, addr, data);
 934		break;
 935	}
 936
 937	return ret;
 938}
 939
 940#ifdef CONFIG_IA32_EMULATION
 941
 942#include <linux/compat.h>
 943#include <linux/syscalls.h>
 944#include <asm/ia32.h>
 945#include <asm/user32.h>
 946
 947#define R32(l,q)							\
 948	case offsetof(struct user32, regs.l):				\
 949		regs->q = value; break
 950
 951#define SEG32(rs)							\
 952	case offsetof(struct user32, regs.rs):				\
 953		return set_segment_reg(child,				\
 954				       offsetof(struct user_regs_struct, rs), \
 955				       value);				\
 956		break
 957
 958static int putreg32(struct task_struct *child, unsigned regno, u32 value)
 959{
 960	struct pt_regs *regs = task_pt_regs(child);
 961
 962	switch (regno) {
 963
 964	SEG32(cs);
 965	SEG32(ds);
 966	SEG32(es);
 967	SEG32(fs);
 968	SEG32(gs);
 969	SEG32(ss);
 970
 971	R32(ebx, bx);
 972	R32(ecx, cx);
 973	R32(edx, dx);
 974	R32(edi, di);
 975	R32(esi, si);
 976	R32(ebp, bp);
 977	R32(eax, ax);
 978	R32(eip, ip);
 979	R32(esp, sp);
 980
 981	case offsetof(struct user32, regs.orig_eax):
 982		/*
 983		 * A 32-bit debugger setting orig_eax means to restore
 984		 * the state of the task restarting a 32-bit syscall.
 985		 * Make sure we interpret the -ERESTART* codes correctly
 986		 * in case the task is not actually still sitting at the
 987		 * exit from a 32-bit syscall with TS_COMPAT still set.
 988		 */
 989		regs->orig_ax = value;
 990		if (syscall_get_nr(child, regs) >= 0)
 991			task_thread_info(child)->status |= TS_COMPAT;
 992		break;
 993
 994	case offsetof(struct user32, regs.eflags):
 995		return set_flags(child, value);
 996
 997	case offsetof(struct user32, u_debugreg[0]) ...
 998		offsetof(struct user32, u_debugreg[7]):
 999		regno -= offsetof(struct user32, u_debugreg[0]);
1000		return ptrace_set_debugreg(child, regno / 4, value);
1001
1002	default:
1003		if (regno > sizeof(struct user32) || (regno & 3))
1004			return -EIO;
1005
1006		/*
1007		 * Other dummy fields in the virtual user structure
1008		 * are ignored
1009		 */
1010		break;
1011	}
1012	return 0;
1013}
1014
1015#undef R32
1016#undef SEG32
1017
1018#define R32(l,q)							\
1019	case offsetof(struct user32, regs.l):				\
1020		*val = regs->q; break
1021
1022#define SEG32(rs)							\
1023	case offsetof(struct user32, regs.rs):				\
1024		*val = get_segment_reg(child,				\
1025				       offsetof(struct user_regs_struct, rs)); \
1026		break
1027
1028static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
1029{
1030	struct pt_regs *regs = task_pt_regs(child);
1031
1032	switch (regno) {
1033
1034	SEG32(ds);
1035	SEG32(es);
1036	SEG32(fs);
1037	SEG32(gs);
1038
1039	R32(cs, cs);
1040	R32(ss, ss);
1041	R32(ebx, bx);
1042	R32(ecx, cx);
1043	R32(edx, dx);
1044	R32(edi, di);
1045	R32(esi, si);
1046	R32(ebp, bp);
1047	R32(eax, ax);
1048	R32(orig_eax, orig_ax);
1049	R32(eip, ip);
1050	R32(esp, sp);
1051
1052	case offsetof(struct user32, regs.eflags):
1053		*val = get_flags(child);
1054		break;
1055
1056	case offsetof(struct user32, u_debugreg[0]) ...
1057		offsetof(struct user32, u_debugreg[7]):
1058		regno -= offsetof(struct user32, u_debugreg[0]);
1059		*val = ptrace_get_debugreg(child, regno / 4);
1060		break;
1061
1062	default:
1063		if (regno > sizeof(struct user32) || (regno & 3))
1064			return -EIO;
1065
1066		/*
1067		 * Other dummy fields in the virtual user structure
1068		 * are ignored
1069		 */
1070		*val = 0;
1071		break;
1072	}
1073	return 0;
1074}
1075
1076#undef R32
1077#undef SEG32
1078
1079static int genregs32_get(struct task_struct *target,
1080			 const struct user_regset *regset,
1081			 unsigned int pos, unsigned int count,
1082			 void *kbuf, void __user *ubuf)
1083{
1084	if (kbuf) {
1085		compat_ulong_t *k = kbuf;
1086		while (count >= sizeof(*k)) {
1087			getreg32(target, pos, k++);
1088			count -= sizeof(*k);
1089			pos += sizeof(*k);
1090		}
1091	} else {
1092		compat_ulong_t __user *u = ubuf;
1093		while (count >= sizeof(*u)) {
1094			compat_ulong_t word;
1095			getreg32(target, pos, &word);
1096			if (__put_user(word, u++))
1097				return -EFAULT;
1098			count -= sizeof(*u);
1099			pos += sizeof(*u);
1100		}
1101	}
1102
1103	return 0;
1104}
1105
1106static int genregs32_set(struct task_struct *target,
1107			 const struct user_regset *regset,
1108			 unsigned int pos, unsigned int count,
1109			 const void *kbuf, const void __user *ubuf)
1110{
1111	int ret = 0;
1112	if (kbuf) {
1113		const compat_ulong_t *k = kbuf;
1114		while (count >= sizeof(*k) && !ret) {
1115			ret = putreg32(target, pos, *k++);
1116			count -= sizeof(*k);
1117			pos += sizeof(*k);
1118		}
1119	} else {
1120		const compat_ulong_t __user *u = ubuf;
1121		while (count >= sizeof(*u) && !ret) {
1122			compat_ulong_t word;
1123			ret = __get_user(word, u++);
1124			if (ret)
1125				break;
1126			ret = putreg32(target, pos, word);
1127			count -= sizeof(*u);
1128			pos += sizeof(*u);
1129		}
1130	}
1131	return ret;
1132}
1133
1134#ifdef CONFIG_X86_X32_ABI
1135static long x32_arch_ptrace(struct task_struct *child,
1136			    compat_long_t request, compat_ulong_t caddr,
1137			    compat_ulong_t cdata)
1138{
1139	unsigned long addr = caddr;
1140	unsigned long data = cdata;
1141	void __user *datap = compat_ptr(data);
1142	int ret;
1143
1144	switch (request) {
1145	/* Read 32bits at location addr in the USER area.  Only allow
1146	   to return the lower 32bits of segment and debug registers.  */
1147	case PTRACE_PEEKUSR: {
1148		u32 tmp;
1149
1150		ret = -EIO;
1151		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1152		    addr < offsetof(struct user_regs_struct, cs))
1153			break;
1154
1155		tmp = 0;  /* Default return condition */
1156		if (addr < sizeof(struct user_regs_struct))
1157			tmp = getreg(child, addr);
1158		else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1159			 addr <= offsetof(struct user, u_debugreg[7])) {
1160			addr -= offsetof(struct user, u_debugreg[0]);
1161			tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1162		}
1163		ret = put_user(tmp, (__u32 __user *)datap);
1164		break;
1165	}
1166
1167	/* Write the word at location addr in the USER area.  Only allow
1168	   to update segment and debug registers with the upper 32bits
1169	   zero-extended. */
1170	case PTRACE_POKEUSR:
1171		ret = -EIO;
1172		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1173		    addr < offsetof(struct user_regs_struct, cs))
1174			break;
1175
1176		if (addr < sizeof(struct user_regs_struct))
1177			ret = putreg(child, addr, data);
1178		else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1179			 addr <= offsetof(struct user, u_debugreg[7])) {
1180			addr -= offsetof(struct user, u_debugreg[0]);
1181			ret = ptrace_set_debugreg(child,
1182						  addr / sizeof(data), data);
1183		}
1184		break;
1185
1186	case PTRACE_GETREGS:	/* Get all gp regs from the child. */
1187		return copy_regset_to_user(child,
1188					   task_user_regset_view(current),
1189					   REGSET_GENERAL,
1190					   0, sizeof(struct user_regs_struct),
1191					   datap);
1192
1193	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
1194		return copy_regset_from_user(child,
1195					     task_user_regset_view(current),
1196					     REGSET_GENERAL,
1197					     0, sizeof(struct user_regs_struct),
1198					     datap);
1199
1200	case PTRACE_GETFPREGS:	/* Get the child FPU state. */
1201		return copy_regset_to_user(child,
1202					   task_user_regset_view(current),
1203					   REGSET_FP,
1204					   0, sizeof(struct user_i387_struct),
1205					   datap);
1206
1207	case PTRACE_SETFPREGS:	/* Set the child FPU state. */
1208		return copy_regset_from_user(child,
1209					     task_user_regset_view(current),
1210					     REGSET_FP,
1211					     0, sizeof(struct user_i387_struct),
1212					     datap);
1213
1214	default:
1215		return compat_ptrace_request(child, request, addr, data);
1216	}
1217
1218	return ret;
1219}
1220#endif
1221
1222long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1223			compat_ulong_t caddr, compat_ulong_t cdata)
1224{
1225	unsigned long addr = caddr;
1226	unsigned long data = cdata;
1227	void __user *datap = compat_ptr(data);
1228	int ret;
1229	__u32 val;
1230
1231#ifdef CONFIG_X86_X32_ABI
1232	if (!is_ia32_task())
1233		return x32_arch_ptrace(child, request, caddr, cdata);
1234#endif
1235
1236	switch (request) {
1237	case PTRACE_PEEKUSR:
1238		ret = getreg32(child, addr, &val);
1239		if (ret == 0)
1240			ret = put_user(val, (__u32 __user *)datap);
1241		break;
1242
1243	case PTRACE_POKEUSR:
1244		ret = putreg32(child, addr, data);
1245		break;
1246
1247	case PTRACE_GETREGS:	/* Get all gp regs from the child. */
1248		return copy_regset_to_user(child, &user_x86_32_view,
1249					   REGSET_GENERAL,
1250					   0, sizeof(struct user_regs_struct32),
1251					   datap);
1252
1253	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
1254		return copy_regset_from_user(child, &user_x86_32_view,
1255					     REGSET_GENERAL, 0,
1256					     sizeof(struct user_regs_struct32),
1257					     datap);
1258
1259	case PTRACE_GETFPREGS:	/* Get the child FPU state. */
1260		return copy_regset_to_user(child, &user_x86_32_view,
1261					   REGSET_FP, 0,
1262					   sizeof(struct user_i387_ia32_struct),
1263					   datap);
1264
1265	case PTRACE_SETFPREGS:	/* Set the child FPU state. */
1266		return copy_regset_from_user(
1267			child, &user_x86_32_view, REGSET_FP,
1268			0, sizeof(struct user_i387_ia32_struct), datap);
1269
1270	case PTRACE_GETFPXREGS:	/* Get the child extended FPU state. */
1271		return copy_regset_to_user(child, &user_x86_32_view,
1272					   REGSET_XFP, 0,
1273					   sizeof(struct user32_fxsr_struct),
1274					   datap);
1275
1276	case PTRACE_SETFPXREGS:	/* Set the child extended FPU state. */
1277		return copy_regset_from_user(child, &user_x86_32_view,
1278					     REGSET_XFP, 0,
1279					     sizeof(struct user32_fxsr_struct),
1280					     datap);
1281
1282	case PTRACE_GET_THREAD_AREA:
1283	case PTRACE_SET_THREAD_AREA:
1284		return arch_ptrace(child, request, addr, data);
1285
1286	default:
1287		return compat_ptrace_request(child, request, addr, data);
1288	}
1289
1290	return ret;
1291}
1292
1293#endif	/* CONFIG_IA32_EMULATION */
1294
1295#ifdef CONFIG_X86_64
1296
1297static struct user_regset x86_64_regsets[] __read_mostly = {
1298	[REGSET_GENERAL] = {
1299		.core_note_type = NT_PRSTATUS,
1300		.n = sizeof(struct user_regs_struct) / sizeof(long),
1301		.size = sizeof(long), .align = sizeof(long),
1302		.get = genregs_get, .set = genregs_set
1303	},
1304	[REGSET_FP] = {
1305		.core_note_type = NT_PRFPREG,
1306		.n = sizeof(struct user_i387_struct) / sizeof(long),
1307		.size = sizeof(long), .align = sizeof(long),
1308		.active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1309	},
1310	[REGSET_XSTATE] = {
1311		.core_note_type = NT_X86_XSTATE,
1312		.size = sizeof(u64), .align = sizeof(u64),
1313		.active = xstateregs_active, .get = xstateregs_get,
1314		.set = xstateregs_set
1315	},
1316	[REGSET_IOPERM64] = {
1317		.core_note_type = NT_386_IOPERM,
1318		.n = IO_BITMAP_LONGS,
1319		.size = sizeof(long), .align = sizeof(long),
1320		.active = ioperm_active, .get = ioperm_get
1321	},
1322};
1323
1324static const struct user_regset_view user_x86_64_view = {
1325	.name = "x86_64", .e_machine = EM_X86_64,
1326	.regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1327};
1328
1329#else  /* CONFIG_X86_32 */
1330
1331#define user_regs_struct32	user_regs_struct
1332#define genregs32_get		genregs_get
1333#define genregs32_set		genregs_set
1334
1335#define user_i387_ia32_struct	user_i387_struct
1336#define user32_fxsr_struct	user_fxsr_struct
1337
1338#endif	/* CONFIG_X86_64 */
1339
1340#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1341static struct user_regset x86_32_regsets[] __read_mostly = {
1342	[REGSET_GENERAL] = {
1343		.core_note_type = NT_PRSTATUS,
1344		.n = sizeof(struct user_regs_struct32) / sizeof(u32),
1345		.size = sizeof(u32), .align = sizeof(u32),
1346		.get = genregs32_get, .set = genregs32_set
1347	},
1348	[REGSET_FP] = {
1349		.core_note_type = NT_PRFPREG,
1350		.n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1351		.size = sizeof(u32), .align = sizeof(u32),
1352		.active = fpregs_active, .get = fpregs_get, .set = fpregs_set
1353	},
1354	[REGSET_XFP] = {
1355		.core_note_type = NT_PRXFPREG,
1356		.n = sizeof(struct user32_fxsr_struct) / sizeof(u32),
1357		.size = sizeof(u32), .align = sizeof(u32),
1358		.active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1359	},
1360	[REGSET_XSTATE] = {
1361		.core_note_type = NT_X86_XSTATE,
1362		.size = sizeof(u64), .align = sizeof(u64),
1363		.active = xstateregs_active, .get = xstateregs_get,
1364		.set = xstateregs_set
1365	},
1366	[REGSET_TLS] = {
1367		.core_note_type = NT_386_TLS,
1368		.n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1369		.size = sizeof(struct user_desc),
1370		.align = sizeof(struct user_desc),
1371		.active = regset_tls_active,
1372		.get = regset_tls_get, .set = regset_tls_set
1373	},
1374	[REGSET_IOPERM32] = {
1375		.core_note_type = NT_386_IOPERM,
1376		.n = IO_BITMAP_BYTES / sizeof(u32),
1377		.size = sizeof(u32), .align = sizeof(u32),
1378		.active = ioperm_active, .get = ioperm_get
1379	},
1380};
1381
1382static const struct user_regset_view user_x86_32_view = {
1383	.name = "i386", .e_machine = EM_386,
1384	.regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1385};
1386#endif
1387
1388/*
1389 * This represents bytes 464..511 in the memory layout exported through
1390 * the REGSET_XSTATE interface.
1391 */
1392u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1393
1394void update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1395{
1396#ifdef CONFIG_X86_64
1397	x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1398#endif
1399#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1400	x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1401#endif
1402	xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1403}
1404
1405const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1406{
1407#ifdef CONFIG_IA32_EMULATION
1408	if (test_tsk_thread_flag(task, TIF_IA32))
1409#endif
1410#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1411		return &user_x86_32_view;
1412#endif
1413#ifdef CONFIG_X86_64
1414	return &user_x86_64_view;
1415#endif
1416}
1417
1418static void fill_sigtrap_info(struct task_struct *tsk,
1419				struct pt_regs *regs,
1420				int error_code, int si_code,
1421				struct siginfo *info)
1422{
1423	tsk->thread.trap_nr = X86_TRAP_DB;
1424	tsk->thread.error_code = error_code;
1425
1426	memset(info, 0, sizeof(*info));
1427	info->si_signo = SIGTRAP;
1428	info->si_code = si_code;
1429	info->si_addr = user_mode_vm(regs) ? (void __user *)regs->ip : NULL;
1430}
1431
1432void user_single_step_siginfo(struct task_struct *tsk,
1433				struct pt_regs *regs,
1434				struct siginfo *info)
1435{
1436	fill_sigtrap_info(tsk, regs, 0, TRAP_BRKPT, info);
1437}
1438
1439void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
1440					 int error_code, int si_code)
1441{
1442	struct siginfo info;
1443
1444	fill_sigtrap_info(tsk, regs, error_code, si_code, &info);
1445	/* Send us the fake SIGTRAP */
1446	force_sig_info(SIGTRAP, &info, tsk);
1447}
1448
1449
1450#ifdef CONFIG_X86_32
1451# define IS_IA32	1
1452#elif defined CONFIG_IA32_EMULATION
1453# define IS_IA32	is_compat_task()
1454#else
1455# define IS_IA32	0
1456#endif
1457
1458/*
1459 * We must return the syscall number to actually look up in the table.
1460 * This can be -1L to skip running any syscall at all.
1461 */
1462long syscall_trace_enter(struct pt_regs *regs)
1463{
1464	long ret = 0;
1465
1466	/*
1467	 * If we stepped into a sysenter/syscall insn, it trapped in
1468	 * kernel mode; do_debug() cleared TF and set TIF_SINGLESTEP.
1469	 * If user-mode had set TF itself, then it's still clear from
1470	 * do_debug() and we need to set it again to restore the user
1471	 * state.  If we entered on the slow path, TF was already set.
1472	 */
1473	if (test_thread_flag(TIF_SINGLESTEP))
1474		regs->flags |= X86_EFLAGS_TF;
1475
1476	/* do the secure computing check first */
1477	if (secure_computing(regs->orig_ax)) {
1478		/* seccomp failures shouldn't expose any additional code. */
1479		ret = -1L;
1480		goto out;
1481	}
1482
1483	if (unlikely(test_thread_flag(TIF_SYSCALL_EMU)))
1484		ret = -1L;
1485
1486	if ((ret || test_thread_flag(TIF_SYSCALL_TRACE)) &&
1487	    tracehook_report_syscall_entry(regs))
1488		ret = -1L;
1489
1490	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1491		trace_sys_enter(regs, regs->orig_ax);
1492
1493	if (IS_IA32)
1494		audit_syscall_entry(AUDIT_ARCH_I386,
1495				    regs->orig_ax,
1496				    regs->bx, regs->cx,
1497				    regs->dx, regs->si);
 
1498#ifdef CONFIG_X86_64
1499	else
1500		audit_syscall_entry(AUDIT_ARCH_X86_64,
1501				    regs->orig_ax,
1502				    regs->di, regs->si,
1503				    regs->dx, regs->r10);
1504#endif
 
1505
1506out:
1507	return ret ?: regs->orig_ax;
1508}
1509
1510void syscall_trace_leave(struct pt_regs *regs)
1511{
1512	bool step;
1513
1514	audit_syscall_exit(regs);
 
1515
1516	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1517		trace_sys_exit(regs, regs->ax);
1518
1519	/*
1520	 * If TIF_SYSCALL_EMU is set, we only get here because of
1521	 * TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP).
1522	 * We already reported this syscall instruction in
1523	 * syscall_trace_enter().
1524	 */
1525	step = unlikely(test_thread_flag(TIF_SINGLESTEP)) &&
1526			!test_thread_flag(TIF_SYSCALL_EMU);
1527	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
1528		tracehook_report_syscall_exit(regs, step);
1529}