1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  linux/arch/arm/kernel/ptrace.c
  4 *
  5 *  By Ross Biro 1/23/92
  6 * edited by Linus Torvalds
  7 * ARM modifications Copyright (C) 2000 Russell King
  8 */
  9#include <linux/kernel.h>
 10#include <linux/sched/signal.h>
 11#include <linux/sched/task_stack.h>
 12#include <linux/mm.h>
 13#include <linux/elf.h>
 14#include <linux/smp.h>
 15#include <linux/ptrace.h>
 16#include <linux/user.h>
 17#include <linux/security.h>
 18#include <linux/init.h>
 19#include <linux/signal.h>
 20#include <linux/uaccess.h>
 21#include <linux/perf_event.h>
 22#include <linux/hw_breakpoint.h>
 23#include <linux/regset.h>
 24#include <linux/audit.h>
 
 25#include <linux/unistd.h>
 26
 27#include <asm/syscall.h>
 28#include <asm/traps.h>
 29
 30#define CREATE_TRACE_POINTS
 31#include <trace/events/syscalls.h>
 32
 33#define REG_PC	15
 34#define REG_PSR	16
 35/*
 36 * does not yet catch signals sent when the child dies.
 37 * in exit.c or in signal.c.
 38 */
 39
 40#if 0
 41/*
 42 * Breakpoint SWI instruction: SWI &9F0001
 43 */
 44#define BREAKINST_ARM	0xef9f0001
 45#define BREAKINST_THUMB	0xdf00		/* fill this in later */
 46#else
 47/*
 48 * New breakpoints - use an undefined instruction.  The ARM architecture
 49 * reference manual guarantees that the following instruction space
 50 * will produce an undefined instruction exception on all CPUs:
 51 *
 52 *  ARM:   xxxx 0111 1111 xxxx xxxx xxxx 1111 xxxx
 53 *  Thumb: 1101 1110 xxxx xxxx
 54 */
 55#define BREAKINST_ARM	0xe7f001f0
 56#define BREAKINST_THUMB	0xde01
 57#endif
 58
 59struct pt_regs_offset {
 60	const char *name;
 61	int offset;
 62};
 63
 64#define REG_OFFSET_NAME(r) \
 65	{.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)}
 66#define REG_OFFSET_END {.name = NULL, .offset = 0}
 67
 68static const struct pt_regs_offset regoffset_table[] = {
 69	REG_OFFSET_NAME(r0),
 70	REG_OFFSET_NAME(r1),
 71	REG_OFFSET_NAME(r2),
 72	REG_OFFSET_NAME(r3),
 73	REG_OFFSET_NAME(r4),
 74	REG_OFFSET_NAME(r5),
 75	REG_OFFSET_NAME(r6),
 76	REG_OFFSET_NAME(r7),
 77	REG_OFFSET_NAME(r8),
 78	REG_OFFSET_NAME(r9),
 79	REG_OFFSET_NAME(r10),
 80	REG_OFFSET_NAME(fp),
 81	REG_OFFSET_NAME(ip),
 82	REG_OFFSET_NAME(sp),
 83	REG_OFFSET_NAME(lr),
 84	REG_OFFSET_NAME(pc),
 85	REG_OFFSET_NAME(cpsr),
 86	REG_OFFSET_NAME(ORIG_r0),
 87	REG_OFFSET_END,
 88};
 89
 90/**
 91 * regs_query_register_offset() - query register offset from its name
 92 * @name:	the name of a register
 93 *
 94 * regs_query_register_offset() returns the offset of a register in struct
 95 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 96 */
 97int regs_query_register_offset(const char *name)
 98{
 99	const struct pt_regs_offset *roff;
100	for (roff = regoffset_table; roff->name != NULL; roff++)
101		if (!strcmp(roff->name, name))
102			return roff->offset;
103	return -EINVAL;
104}
105
106/**
107 * regs_query_register_name() - query register name from its offset
108 * @offset:	the offset of a register in struct pt_regs.
109 *
110 * regs_query_register_name() returns the name of a register from its
111 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
112 */
113const char *regs_query_register_name(unsigned int offset)
114{
115	const struct pt_regs_offset *roff;
116	for (roff = regoffset_table; roff->name != NULL; roff++)
117		if (roff->offset == offset)
118			return roff->name;
119	return NULL;
120}
121
122/**
123 * regs_within_kernel_stack() - check the address in the stack
124 * @regs:      pt_regs which contains kernel stack pointer.
125 * @addr:      address which is checked.
126 *
127 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
128 * If @addr is within the kernel stack, it returns true. If not, returns false.
129 */
130bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
131{
132	return ((addr & ~(THREAD_SIZE - 1))  ==
133		(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
134}
135
136/**
137 * regs_get_kernel_stack_nth() - get Nth entry of the stack
138 * @regs:	pt_regs which contains kernel stack pointer.
139 * @n:		stack entry number.
140 *
141 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
142 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
143 * this returns 0.
144 */
145unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
146{
147	unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
148	addr += n;
149	if (regs_within_kernel_stack(regs, (unsigned long)addr))
150		return *addr;
151	else
152		return 0;
153}
154
155/*
156 * this routine will get a word off of the processes privileged stack.
157 * the offset is how far from the base addr as stored in the THREAD.
158 * this routine assumes that all the privileged stacks are in our
159 * data space.
160 */
161static inline long get_user_reg(struct task_struct *task, int offset)
162{
163	return task_pt_regs(task)->uregs[offset];
164}
165
166/*
167 * this routine will put a word on the processes privileged stack.
168 * the offset is how far from the base addr as stored in the THREAD.
169 * this routine assumes that all the privileged stacks are in our
170 * data space.
171 */
172static inline int
173put_user_reg(struct task_struct *task, int offset, long data)
174{
175	struct pt_regs newregs, *regs = task_pt_regs(task);
176	int ret = -EINVAL;
177
178	newregs = *regs;
179	newregs.uregs[offset] = data;
180
181	if (valid_user_regs(&newregs)) {
182		regs->uregs[offset] = data;
183		ret = 0;
184	}
185
186	return ret;
187}
188
189/*
190 * Called by kernel/ptrace.c when detaching..
191 */
192void ptrace_disable(struct task_struct *child)
193{
194	/* Nothing to do. */
195}
196
197/*
198 * Handle hitting a breakpoint.
199 */
200void ptrace_break(struct pt_regs *regs)
201{
202	force_sig_fault(SIGTRAP, TRAP_BRKPT,
203			(void __user *)instruction_pointer(regs));
204}
205
206static int break_trap(struct pt_regs *regs, unsigned int instr)
207{
208	ptrace_break(regs);
209	return 0;
210}
211
212static struct undef_hook arm_break_hook = {
213	.instr_mask	= 0x0fffffff,
214	.instr_val	= 0x07f001f0,
215	.cpsr_mask	= PSR_T_BIT,
216	.cpsr_val	= 0,
217	.fn		= break_trap,
218};
219
220static struct undef_hook thumb_break_hook = {
221	.instr_mask	= 0xffffffff,
222	.instr_val	= 0x0000de01,
223	.cpsr_mask	= PSR_T_BIT,
224	.cpsr_val	= PSR_T_BIT,
225	.fn		= break_trap,
226};
227
228static struct undef_hook thumb2_break_hook = {
229	.instr_mask	= 0xffffffff,
230	.instr_val	= 0xf7f0a000,
231	.cpsr_mask	= PSR_T_BIT,
232	.cpsr_val	= PSR_T_BIT,
233	.fn		= break_trap,
234};
235
236static int __init ptrace_break_init(void)
237{
238	register_undef_hook(&arm_break_hook);
239	register_undef_hook(&thumb_break_hook);
240	register_undef_hook(&thumb2_break_hook);
241	return 0;
242}
243
244core_initcall(ptrace_break_init);
245
246/*
247 * Read the word at offset "off" into the "struct user".  We
248 * actually access the pt_regs stored on the kernel stack.
249 */
250static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
251			    unsigned long __user *ret)
252{
253	unsigned long tmp;
254
255	if (off & 3)
256		return -EIO;
257
258	tmp = 0;
259	if (off == PT_TEXT_ADDR)
260		tmp = tsk->mm->start_code;
261	else if (off == PT_DATA_ADDR)
262		tmp = tsk->mm->start_data;
263	else if (off == PT_TEXT_END_ADDR)
264		tmp = tsk->mm->end_code;
265	else if (off < sizeof(struct pt_regs))
266		tmp = get_user_reg(tsk, off >> 2);
267	else if (off >= sizeof(struct user))
268		return -EIO;
269
270	return put_user(tmp, ret);
271}
272
273/*
274 * Write the word at offset "off" into "struct user".  We
275 * actually access the pt_regs stored on the kernel stack.
276 */
277static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
278			     unsigned long val)
279{
280	if (off & 3 || off >= sizeof(struct user))
281		return -EIO;
282
283	if (off >= sizeof(struct pt_regs))
284		return 0;
285
286	return put_user_reg(tsk, off >> 2, val);
287}
288
289#ifdef CONFIG_IWMMXT
290
291/*
292 * Get the child iWMMXt state.
293 */
294static int ptrace_getwmmxregs(struct task_struct *tsk, void __user *ufp)
295{
296	struct thread_info *thread = task_thread_info(tsk);
297
298	if (!test_ti_thread_flag(thread, TIF_USING_IWMMXT))
299		return -ENODATA;
300	iwmmxt_task_disable(thread);  /* force it to ram */
301	return copy_to_user(ufp, &thread->fpstate.iwmmxt, IWMMXT_SIZE)
302		? -EFAULT : 0;
303}
304
305/*
306 * Set the child iWMMXt state.
307 */
308static int ptrace_setwmmxregs(struct task_struct *tsk, void __user *ufp)
309{
310	struct thread_info *thread = task_thread_info(tsk);
311
312	if (!test_ti_thread_flag(thread, TIF_USING_IWMMXT))
313		return -EACCES;
314	iwmmxt_task_release(thread);  /* force a reload */
315	return copy_from_user(&thread->fpstate.iwmmxt, ufp, IWMMXT_SIZE)
316		? -EFAULT : 0;
317}
318
319#endif
320
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
321#ifdef CONFIG_HAVE_HW_BREAKPOINT
322/*
323 * Convert a virtual register number into an index for a thread_info
324 * breakpoint array. Breakpoints are identified using positive numbers
325 * whilst watchpoints are negative. The registers are laid out as pairs
326 * of (address, control), each pair mapping to a unique hw_breakpoint struct.
327 * Register 0 is reserved for describing resource information.
328 */
329static int ptrace_hbp_num_to_idx(long num)
330{
331	if (num < 0)
332		num = (ARM_MAX_BRP << 1) - num;
333	return (num - 1) >> 1;
334}
335
336/*
337 * Returns the virtual register number for the address of the
338 * breakpoint at index idx.
339 */
340static long ptrace_hbp_idx_to_num(int idx)
341{
342	long mid = ARM_MAX_BRP << 1;
343	long num = (idx << 1) + 1;
344	return num > mid ? mid - num : num;
345}
346
347/*
348 * Handle hitting a HW-breakpoint.
349 */
350static void ptrace_hbptriggered(struct perf_event *bp,
351				     struct perf_sample_data *data,
352				     struct pt_regs *regs)
353{
354	struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
355	long num;
356	int i;
357
358	for (i = 0; i < ARM_MAX_HBP_SLOTS; ++i)
359		if (current->thread.debug.hbp[i] == bp)
360			break;
361
362	num = (i == ARM_MAX_HBP_SLOTS) ? 0 : ptrace_hbp_idx_to_num(i);
363
364	force_sig_ptrace_errno_trap((int)num, (void __user *)(bkpt->trigger));
365}
366
367/*
368 * Set ptrace breakpoint pointers to zero for this task.
369 * This is required in order to prevent child processes from unregistering
370 * breakpoints held by their parent.
371 */
372void clear_ptrace_hw_breakpoint(struct task_struct *tsk)
373{
374	memset(tsk->thread.debug.hbp, 0, sizeof(tsk->thread.debug.hbp));
375}
376
377/*
378 * Unregister breakpoints from this task and reset the pointers in
379 * the thread_struct.
380 */
381void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
382{
383	int i;
384	struct thread_struct *t = &tsk->thread;
385
386	for (i = 0; i < ARM_MAX_HBP_SLOTS; i++) {
387		if (t->debug.hbp[i]) {
388			unregister_hw_breakpoint(t->debug.hbp[i]);
389			t->debug.hbp[i] = NULL;
390		}
391	}
392}
393
394static u32 ptrace_get_hbp_resource_info(void)
395{
396	u8 num_brps, num_wrps, debug_arch, wp_len;
397	u32 reg = 0;
398
399	num_brps	= hw_breakpoint_slots(TYPE_INST);
400	num_wrps	= hw_breakpoint_slots(TYPE_DATA);
401	debug_arch	= arch_get_debug_arch();
402	wp_len		= arch_get_max_wp_len();
403
404	reg		|= debug_arch;
405	reg		<<= 8;
406	reg		|= wp_len;
407	reg		<<= 8;
408	reg		|= num_wrps;
409	reg		<<= 8;
410	reg		|= num_brps;
411
412	return reg;
413}
414
415static struct perf_event *ptrace_hbp_create(struct task_struct *tsk, int type)
416{
417	struct perf_event_attr attr;
418
419	ptrace_breakpoint_init(&attr);
420
421	/* Initialise fields to sane defaults. */
422	attr.bp_addr	= 0;
423	attr.bp_len	= HW_BREAKPOINT_LEN_4;
424	attr.bp_type	= type;
425	attr.disabled	= 1;
426
427	return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,
428					   tsk);
429}
430
431static int ptrace_gethbpregs(struct task_struct *tsk, long num,
432			     unsigned long  __user *data)
433{
434	u32 reg;
435	int idx, ret = 0;
436	struct perf_event *bp;
437	struct arch_hw_breakpoint_ctrl arch_ctrl;
438
439	if (num == 0) {
440		reg = ptrace_get_hbp_resource_info();
441	} else {
442		idx = ptrace_hbp_num_to_idx(num);
443		if (idx < 0 || idx >= ARM_MAX_HBP_SLOTS) {
444			ret = -EINVAL;
445			goto out;
446		}
447
448		bp = tsk->thread.debug.hbp[idx];
449		if (!bp) {
450			reg = 0;
451			goto put;
452		}
453
454		arch_ctrl = counter_arch_bp(bp)->ctrl;
455
456		/*
457		 * Fix up the len because we may have adjusted it
458		 * to compensate for an unaligned address.
459		 */
460		while (!(arch_ctrl.len & 0x1))
461			arch_ctrl.len >>= 1;
462
463		if (num & 0x1)
464			reg = bp->attr.bp_addr;
465		else
466			reg = encode_ctrl_reg(arch_ctrl);
467	}
468
469put:
470	if (put_user(reg, data))
471		ret = -EFAULT;
472
473out:
474	return ret;
475}
476
477static int ptrace_sethbpregs(struct task_struct *tsk, long num,
478			     unsigned long __user *data)
479{
480	int idx, gen_len, gen_type, implied_type, ret = 0;
481	u32 user_val;
482	struct perf_event *bp;
483	struct arch_hw_breakpoint_ctrl ctrl;
484	struct perf_event_attr attr;
485
486	if (num == 0)
487		goto out;
488	else if (num < 0)
489		implied_type = HW_BREAKPOINT_RW;
490	else
491		implied_type = HW_BREAKPOINT_X;
492
493	idx = ptrace_hbp_num_to_idx(num);
494	if (idx < 0 || idx >= ARM_MAX_HBP_SLOTS) {
495		ret = -EINVAL;
496		goto out;
497	}
498
499	if (get_user(user_val, data)) {
500		ret = -EFAULT;
501		goto out;
502	}
503
504	bp = tsk->thread.debug.hbp[idx];
505	if (!bp) {
506		bp = ptrace_hbp_create(tsk, implied_type);
507		if (IS_ERR(bp)) {
508			ret = PTR_ERR(bp);
509			goto out;
510		}
511		tsk->thread.debug.hbp[idx] = bp;
512	}
513
514	attr = bp->attr;
515
516	if (num & 0x1) {
517		/* Address */
518		attr.bp_addr	= user_val;
519	} else {
520		/* Control */
521		decode_ctrl_reg(user_val, &ctrl);
522		ret = arch_bp_generic_fields(ctrl, &gen_len, &gen_type);
523		if (ret)
524			goto out;
525
526		if ((gen_type & implied_type) != gen_type) {
527			ret = -EINVAL;
528			goto out;
529		}
530
531		attr.bp_len	= gen_len;
532		attr.bp_type	= gen_type;
533		attr.disabled	= !ctrl.enabled;
534	}
535
536	ret = modify_user_hw_breakpoint(bp, &attr);
537out:
538	return ret;
539}
540#endif
541
542/* regset get/set implementations */
543
544static int gpr_get(struct task_struct *target,
545		   const struct user_regset *regset,
546		   struct membuf to)
547{
548	return membuf_write(&to, task_pt_regs(target), sizeof(struct pt_regs));
549}
550
551static int gpr_set(struct task_struct *target,
552		   const struct user_regset *regset,
553		   unsigned int pos, unsigned int count,
554		   const void *kbuf, const void __user *ubuf)
555{
556	int ret;
557	struct pt_regs newregs = *task_pt_regs(target);
558
559	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
560				 &newregs,
561				 0, sizeof(newregs));
562	if (ret)
563		return ret;
564
565	if (!valid_user_regs(&newregs))
566		return -EINVAL;
567
568	*task_pt_regs(target) = newregs;
569	return 0;
570}
571
572static int fpa_get(struct task_struct *target,
573		   const struct user_regset *regset,
574		   struct membuf to)
575{
576	return membuf_write(&to, &task_thread_info(target)->fpstate,
577				 sizeof(struct user_fp));
578}
579
580static int fpa_set(struct task_struct *target,
581		   const struct user_regset *regset,
582		   unsigned int pos, unsigned int count,
583		   const void *kbuf, const void __user *ubuf)
584{
585	struct thread_info *thread = task_thread_info(target);
586
 
 
587	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
588		&thread->fpstate,
589		0, sizeof(struct user_fp));
590}
591
592#ifdef CONFIG_VFP
593/*
594 * VFP register get/set implementations.
595 *
596 * With respect to the kernel, struct user_fp is divided into three chunks:
597 * 16 or 32 real VFP registers (d0-d15 or d0-31)
598 *	These are transferred to/from the real registers in the task's
599 *	vfp_hard_struct.  The number of registers depends on the kernel
600 *	configuration.
601 *
602 * 16 or 0 fake VFP registers (d16-d31 or empty)
603 *	i.e., the user_vfp structure has space for 32 registers even if
604 *	the kernel doesn't have them all.
605 *
606 *	vfp_get() reads this chunk as zero where applicable
607 *	vfp_set() ignores this chunk
608 *
609 * 1 word for the FPSCR
610 */
611static int vfp_get(struct task_struct *target,
612		   const struct user_regset *regset,
613		   struct membuf to)
614{
615	struct thread_info *thread = task_thread_info(target);
616	struct vfp_hard_struct const *vfp = &thread->vfpstate.hard;
617	const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
618
619	vfp_sync_hwstate(thread);
620
621	membuf_write(&to, vfp->fpregs, sizeof(vfp->fpregs));
622	membuf_zero(&to, user_fpscr_offset - sizeof(vfp->fpregs));
623	return membuf_store(&to, vfp->fpscr);
624}
625
626/*
627 * For vfp_set() a read-modify-write is done on the VFP registers,
628 * in order to avoid writing back a half-modified set of registers on
629 * failure.
630 */
631static int vfp_set(struct task_struct *target,
632			  const struct user_regset *regset,
633			  unsigned int pos, unsigned int count,
634			  const void *kbuf, const void __user *ubuf)
635{
636	int ret;
637	struct thread_info *thread = task_thread_info(target);
638	struct vfp_hard_struct new_vfp;
639	const size_t user_fpregs_offset = offsetof(struct user_vfp, fpregs);
640	const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
641
642	vfp_sync_hwstate(thread);
643	new_vfp = thread->vfpstate.hard;
644
645	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
646				  &new_vfp.fpregs,
647				  user_fpregs_offset,
648				  user_fpregs_offset + sizeof(new_vfp.fpregs));
649	if (ret)
650		return ret;
651
652	user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
653				  user_fpregs_offset + sizeof(new_vfp.fpregs),
654				  user_fpscr_offset);
 
 
655
656	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
657				 &new_vfp.fpscr,
658				 user_fpscr_offset,
659				 user_fpscr_offset + sizeof(new_vfp.fpscr));
660	if (ret)
661		return ret;
662
663	thread->vfpstate.hard = new_vfp;
664	vfp_flush_hwstate(thread);
665
666	return 0;
667}
668#endif /* CONFIG_VFP */
669
670enum arm_regset {
671	REGSET_GPR,
672	REGSET_FPR,
673#ifdef CONFIG_VFP
674	REGSET_VFP,
675#endif
676};
677
678static const struct user_regset arm_regsets[] = {
679	[REGSET_GPR] = {
680		.core_note_type = NT_PRSTATUS,
681		.n = ELF_NGREG,
682		.size = sizeof(u32),
683		.align = sizeof(u32),
684		.regset_get = gpr_get,
685		.set = gpr_set
686	},
687	[REGSET_FPR] = {
688		/*
689		 * For the FPA regs in fpstate, the real fields are a mixture
690		 * of sizes, so pretend that the registers are word-sized:
691		 */
692		.core_note_type = NT_PRFPREG,
693		.n = sizeof(struct user_fp) / sizeof(u32),
694		.size = sizeof(u32),
695		.align = sizeof(u32),
696		.regset_get = fpa_get,
697		.set = fpa_set
698	},
699#ifdef CONFIG_VFP
700	[REGSET_VFP] = {
701		/*
702		 * Pretend that the VFP regs are word-sized, since the FPSCR is
703		 * a single word dangling at the end of struct user_vfp:
704		 */
705		.core_note_type = NT_ARM_VFP,
706		.n = ARM_VFPREGS_SIZE / sizeof(u32),
707		.size = sizeof(u32),
708		.align = sizeof(u32),
709		.regset_get = vfp_get,
710		.set = vfp_set
711	},
712#endif /* CONFIG_VFP */
713};
714
715static const struct user_regset_view user_arm_view = {
716	.name = "arm", .e_machine = ELF_ARCH, .ei_osabi = ELF_OSABI,
717	.regsets = arm_regsets, .n = ARRAY_SIZE(arm_regsets)
718};
719
720const struct user_regset_view *task_user_regset_view(struct task_struct *task)
721{
722	return &user_arm_view;
723}
724
725long arch_ptrace(struct task_struct *child, long request,
726		 unsigned long addr, unsigned long data)
727{
728	int ret;
729	unsigned long __user *datap = (unsigned long __user *) data;
730
731	switch (request) {
732		case PTRACE_PEEKUSR:
733			ret = ptrace_read_user(child, addr, datap);
734			break;
735
736		case PTRACE_POKEUSR:
737			ret = ptrace_write_user(child, addr, data);
738			break;
739
740		case PTRACE_GETREGS:
741			ret = copy_regset_to_user(child,
742						  &user_arm_view, REGSET_GPR,
743						  0, sizeof(struct pt_regs),
744						  datap);
745			break;
746
747		case PTRACE_SETREGS:
748			ret = copy_regset_from_user(child,
749						    &user_arm_view, REGSET_GPR,
750						    0, sizeof(struct pt_regs),
751						    datap);
752			break;
753
754		case PTRACE_GETFPREGS:
755			ret = copy_regset_to_user(child,
756						  &user_arm_view, REGSET_FPR,
757						  0, sizeof(union fp_state),
758						  datap);
759			break;
760
761		case PTRACE_SETFPREGS:
762			ret = copy_regset_from_user(child,
763						    &user_arm_view, REGSET_FPR,
764						    0, sizeof(union fp_state),
765						    datap);
766			break;
767
768#ifdef CONFIG_IWMMXT
769		case PTRACE_GETWMMXREGS:
770			ret = ptrace_getwmmxregs(child, datap);
771			break;
772
773		case PTRACE_SETWMMXREGS:
774			ret = ptrace_setwmmxregs(child, datap);
775			break;
776#endif
777
778		case PTRACE_GET_THREAD_AREA:
779			ret = put_user(task_thread_info(child)->tp_value[0],
780				       datap);
781			break;
782
783		case PTRACE_SET_SYSCALL:
784			if (data != -1)
785				data &= __NR_SYSCALL_MASK;
786			task_thread_info(child)->abi_syscall = data;
787			ret = 0;
788			break;
789
 
 
 
 
 
 
 
 
 
 
790#ifdef CONFIG_VFP
791		case PTRACE_GETVFPREGS:
792			ret = copy_regset_to_user(child,
793						  &user_arm_view, REGSET_VFP,
794						  0, ARM_VFPREGS_SIZE,
795						  datap);
796			break;
797
798		case PTRACE_SETVFPREGS:
799			ret = copy_regset_from_user(child,
800						    &user_arm_view, REGSET_VFP,
801						    0, ARM_VFPREGS_SIZE,
802						    datap);
803			break;
804#endif
805
806#ifdef CONFIG_HAVE_HW_BREAKPOINT
807		case PTRACE_GETHBPREGS:
808			ret = ptrace_gethbpregs(child, addr,
809						(unsigned long __user *)data);
810			break;
811		case PTRACE_SETHBPREGS:
812			ret = ptrace_sethbpregs(child, addr,
813						(unsigned long __user *)data);
814			break;
815#endif
816
817		default:
818			ret = ptrace_request(child, request, addr, data);
819			break;
820	}
821
822	return ret;
823}
824
825enum ptrace_syscall_dir {
826	PTRACE_SYSCALL_ENTER = 0,
827	PTRACE_SYSCALL_EXIT,
828};
829
830static void report_syscall(struct pt_regs *regs, enum ptrace_syscall_dir dir)
 
831{
832	unsigned long ip;
833
834	/*
835	 * IP is used to denote syscall entry/exit:
836	 * IP = 0 -> entry, =1 -> exit
837	 */
838	ip = regs->ARM_ip;
839	regs->ARM_ip = dir;
840
841	if (dir == PTRACE_SYSCALL_EXIT)
842		ptrace_report_syscall_exit(regs, 0);
843	else if (ptrace_report_syscall_entry(regs))
844		current_thread_info()->abi_syscall = -1;
845
846	regs->ARM_ip = ip;
847}
848
849asmlinkage int syscall_trace_enter(struct pt_regs *regs)
850{
851	int scno;
852
853	if (test_thread_flag(TIF_SYSCALL_TRACE))
854		report_syscall(regs, PTRACE_SYSCALL_ENTER);
855
856	/* Do seccomp after ptrace; syscall may have changed. */
857#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER
858	if (secure_computing() == -1)
859		return -1;
860#else
861	/* XXX: remove this once OABI gets fixed */
862	secure_computing_strict(syscall_get_nr(current, regs));
863#endif
864
865	/* Tracer or seccomp may have changed syscall. */
866	scno = syscall_get_nr(current, regs);
867
868	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
869		trace_sys_enter(regs, scno);
870
871	audit_syscall_entry(scno, regs->ARM_r0, regs->ARM_r1, regs->ARM_r2,
872			    regs->ARM_r3);
873
874	return scno;
875}
876
877asmlinkage void syscall_trace_exit(struct pt_regs *regs)
878{
879	/*
880	 * Audit the syscall before anything else, as a debugger may
881	 * come in and change the current registers.
882	 */
883	audit_syscall_exit(regs);
884
885	/*
886	 * Note that we haven't updated the ->syscall field for the
887	 * current thread. This isn't a problem because it will have
888	 * been set on syscall entry and there hasn't been an opportunity
889	 * for a PTRACE_SET_SYSCALL since then.
890	 */
891	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
892		trace_sys_exit(regs, regs_return_value(regs));
893
894	if (test_thread_flag(TIF_SYSCALL_TRACE))
895		report_syscall(regs, PTRACE_SYSCALL_EXIT);
896}