[linux-2.6-block.git] / arch / alpha / kernel / ptrace.c

// SPDX-License-Identifier: GPL-2.0
/* ptrace.c */
/* By Ross Biro 1/23/92 */
/* edited by Linus Torvalds */
/* mangled further by Bob Manson (manson@santafe.edu) */
/* more mutilation by David Mosberger (davidm@azstarnet.com) */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <linux/tracehook.h>
#include <linux/audit.h>

#include <linux/uaccess.h>
#include <asm/pgtable.h>
#include <asm/fpu.h>

#include "proto.h"

#define DEBUG	DBG_MEM
#undef DEBUG

#ifdef DEBUG
enum {
	DBG_MEM		= (1<<0),
	DBG_BPT		= (1<<1),
	DBG_MEM_ALL	= (1<<2)
};
#define DBG(fac,args)	{if ((fac) & DEBUG) printk args;}
#else
#define DBG(fac,args)
#endif

#define BREAKINST	0x00000080	/* call_pal bpt */

/*
 * does not yet catch signals sent when the child dies.
 * in exit.c or in signal.c.
 */

/*
 * Processes always block with the following stack-layout:
 *
 *  +================================+ <---- task + 2*PAGE_SIZE
 *  | PALcode saved frame (ps, pc,   | ^
 *  | gp, a0, a1, a2)		     | |
 *  +================================+ | struct pt_regs
 *  |	        		     | |
 *  | frame generated by SAVE_ALL    | |
 *  |	        		     | v
 *  +================================+
 *  |	        		     | ^
 *  | frame saved by do_switch_stack | | struct switch_stack
 *  |	        		     | v
 *  +================================+
 */

/* 
 * The following table maps a register index into the stack offset at
 * which the register is saved.  Register indices are 0-31 for integer
 * regs, 32-63 for fp regs, and 64 for the pc.  Notice that sp and
 * zero have no stack-slot and need to be treated specially (see
 * get_reg/put_reg below).
 */
enum {
	REG_R0 = 0, REG_F0 = 32, REG_FPCR = 63, REG_PC = 64
};

#define PT_REG(reg) \
  (PAGE_SIZE*2 - sizeof(struct pt_regs) + offsetof(struct pt_regs, reg))

#define SW_REG(reg) \
 (PAGE_SIZE*2 - sizeof(struct pt_regs) - sizeof(struct switch_stack) \
  + offsetof(struct switch_stack, reg))

static int regoff[] = {
	PT_REG(	   r0), PT_REG(	   r1), PT_REG(	   r2), PT_REG(	  r3),
	PT_REG(	   r4), PT_REG(	   r5), PT_REG(	   r6), PT_REG(	  r7),
	PT_REG(	   r8), SW_REG(	   r9), SW_REG(	  r10), SW_REG(	 r11),
	SW_REG(	  r12), SW_REG(	  r13), SW_REG(	  r14), SW_REG(	 r15),
	PT_REG(	  r16), PT_REG(	  r17), PT_REG(	  r18), PT_REG(	 r19),
	PT_REG(	  r20), PT_REG(	  r21), PT_REG(	  r22), PT_REG(	 r23),
	PT_REG(	  r24), PT_REG(	  r25), PT_REG(	  r26), PT_REG(	 r27),
	PT_REG(	  r28), PT_REG(	   gp),		   -1,		   -1,
	SW_REG(fp[ 0]), SW_REG(fp[ 1]), SW_REG(fp[ 2]), SW_REG(fp[ 3]),
	SW_REG(fp[ 4]), SW_REG(fp[ 5]), SW_REG(fp[ 6]), SW_REG(fp[ 7]),
	SW_REG(fp[ 8]), SW_REG(fp[ 9]), SW_REG(fp[10]), SW_REG(fp[11]),
	SW_REG(fp[12]), SW_REG(fp[13]), SW_REG(fp[14]), SW_REG(fp[15]),
	SW_REG(fp[16]), SW_REG(fp[17]), SW_REG(fp[18]), SW_REG(fp[19]),
	SW_REG(fp[20]), SW_REG(fp[21]), SW_REG(fp[22]), SW_REG(fp[23]),
	SW_REG(fp[24]), SW_REG(fp[25]), SW_REG(fp[26]), SW_REG(fp[27]),
	SW_REG(fp[28]), SW_REG(fp[29]), SW_REG(fp[30]), SW_REG(fp[31]),
	PT_REG(	   pc)
};

static unsigned long zero;

/*
 * Get address of register REGNO in task TASK.
 */
static unsigned long *
get_reg_addr(struct task_struct * task, unsigned long regno)
{
	unsigned long *addr;

	if (regno == 30) {
		addr = &task_thread_info(task)->pcb.usp;
	} else if (regno == 65) {
		addr = &task_thread_info(task)->pcb.unique;
	} else if (regno == 31 || regno > 65) {
		zero = 0;
		addr = &zero;
	} else {
		addr = task_stack_page(task) + regoff[regno];
	}
	return addr;
}

/*
 * Get contents of register REGNO in task TASK.
 */
static unsigned long
get_reg(struct task_struct * task, unsigned long regno)
{
	/* Special hack for fpcr -- combine hardware and software bits.  */
	if (regno == 63) {
		unsigned long fpcr = *get_reg_addr(task, regno);
		unsigned long swcr
		  = task_thread_info(task)->ieee_state & IEEE_SW_MASK;
		swcr = swcr_update_status(swcr, fpcr);
		return fpcr | swcr;
	}
	return *get_reg_addr(task, regno);
}

/*
 * Write contents of register REGNO in task TASK.
 */
static int
put_reg(struct task_struct *task, unsigned long regno, unsigned long data)
{
	if (regno == 63) {
		task_thread_info(task)->ieee_state
		  = ((task_thread_info(task)->ieee_state & ~IEEE_SW_MASK)
		     | (data & IEEE_SW_MASK));
		data = (data & FPCR_DYN_MASK) | ieee_swcr_to_fpcr(data);
	}
	*get_reg_addr(task, regno) = data;
	return 0;
}

static inline int
read_int(struct task_struct *task, unsigned long addr, int * data)
{
	int copied = access_process_vm(task, addr, data, sizeof(int),
			FOLL_FORCE);
	return (copied == sizeof(int)) ? 0 : -EIO;
}

static inline int
write_int(struct task_struct *task, unsigned long addr, int data)
{
	int copied = access_process_vm(task, addr, &data, sizeof(int),
			FOLL_FORCE | FOLL_WRITE);
	return (copied == sizeof(int)) ? 0 : -EIO;
}

/*
 * Set breakpoint.
 */
int
ptrace_set_bpt(struct task_struct * child)
{
	int displ, i, res, reg_b, nsaved = 0;
	unsigned int insn, op_code;
	unsigned long pc;

	pc  = get_reg(child, REG_PC);
	res = read_int(child, pc, (int *) &insn);
	if (res < 0)
		return res;

	op_code = insn >> 26;
	if (op_code >= 0x30) {
		/*
		 * It's a branch: instead of trying to figure out
		 * whether the branch will be taken or not, we'll put
		 * a breakpoint at either location.  This is simpler,
		 * more reliable, and probably not a whole lot slower
		 * than the alternative approach of emulating the
		 * branch (emulation can be tricky for fp branches).
		 */
		displ = ((s32)(insn << 11)) >> 9;
		task_thread_info(child)->bpt_addr[nsaved++] = pc + 4;
		if (displ)		/* guard against unoptimized code */
			task_thread_info(child)->bpt_addr[nsaved++]
			  = pc + 4 + displ;
		DBG(DBG_BPT, ("execing branch\n"));
	} else if (op_code == 0x1a) {
		reg_b = (insn >> 16) & 0x1f;
		task_thread_info(child)->bpt_addr[nsaved++] = get_reg(child, reg_b);
		DBG(DBG_BPT, ("execing jump\n"));
	} else {
		task_thread_info(child)->bpt_addr[nsaved++] = pc + 4;
		DBG(DBG_BPT, ("execing normal insn\n"));
	}

	/* install breakpoints: */
	for (i = 0; i < nsaved; ++i) {
		res = read_int(child, task_thread_info(child)->bpt_addr[i],
			       (int *) &insn);
		if (res < 0)
			return res;
		task_thread_info(child)->bpt_insn[i] = insn;
		DBG(DBG_BPT, ("    -> next_pc=%lx\n",
			      task_thread_info(child)->bpt_addr[i]));
		res = write_int(child, task_thread_info(child)->bpt_addr[i],
				BREAKINST);
		if (res < 0)
			return res;
	}
	task_thread_info(child)->bpt_nsaved = nsaved;
	return 0;
}

/*
 * Ensure no single-step breakpoint is pending.  Returns non-zero
 * value if child was being single-stepped.
 */
int
ptrace_cancel_bpt(struct task_struct * child)
{
	int i, nsaved = task_thread_info(child)->bpt_nsaved;

	task_thread_info(child)->bpt_nsaved = 0;

	if (nsaved > 2) {
		printk("ptrace_cancel_bpt: bogus nsaved: %d!\n", nsaved);
		nsaved = 2;
	}

	for (i = 0; i < nsaved; ++i) {
		write_int(child, task_thread_info(child)->bpt_addr[i],
			  task_thread_info(child)->bpt_insn[i]);
	}
	return (nsaved != 0);
}

void user_enable_single_step(struct task_struct *child)
{
	/* Mark single stepping.  */
	task_thread_info(child)->bpt_nsaved = -1;
}

void user_disable_single_step(struct task_struct *child)
{
	ptrace_cancel_bpt(child);
}

/*
 * Called by kernel/ptrace.c when detaching..
 *
 * Make sure the single step bit is not set.
 */
void ptrace_disable(struct task_struct *child)
{ 
	user_disable_single_step(child);
}

long arch_ptrace(struct task_struct *child, long request,
		 unsigned long addr, unsigned long data)
{
	unsigned long tmp;
	size_t copied;
	long ret;

	switch (request) {
	/* When I and D space are separate, these will need to be fixed.  */
	case PTRACE_PEEKTEXT: /* read word at location addr. */
	case PTRACE_PEEKDATA:
		copied = ptrace_access_vm(child, addr, &tmp, sizeof(tmp),
				FOLL_FORCE);
		ret = -EIO;
		if (copied != sizeof(tmp))
			break;
		
		force_successful_syscall_return();
		ret = tmp;
		break;

	/* Read register number ADDR. */
	case PTRACE_PEEKUSR:
		force_successful_syscall_return();
		ret = get_reg(child, addr);
		DBG(DBG_MEM, ("peek $%lu->%#lx\n", addr, ret));
		break;

	/* When I and D space are separate, this will have to be fixed.  */
	case PTRACE_POKETEXT: /* write the word at location addr. */
	case PTRACE_POKEDATA:
		ret = generic_ptrace_pokedata(child, addr, data);
		break;

	case PTRACE_POKEUSR: /* write the specified register */
		DBG(DBG_MEM, ("poke $%lu<-%#lx\n", addr, data));
		ret = put_reg(child, addr, data);
		break;
	default:
		ret = ptrace_request(child, request, addr, data);
		break;
	}
	return ret;
}

asmlinkage unsigned long syscall_trace_enter(void)
{
	unsigned long ret = 0;
	struct pt_regs *regs = current_pt_regs();
	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
	    tracehook_report_syscall_entry(current_pt_regs()))
		ret = -1UL;
	audit_syscall_entry(regs->r0, regs->r16, regs->r17, regs->r18, regs->r19);
	return ret ?: current_pt_regs()->r0;
}

asmlinkage void
syscall_trace_leave(void)
{
	audit_syscall_exit(current_pt_regs());
	if (test_thread_flag(TIF_SYSCALL_TRACE))
		tracehook_report_syscall_exit(current_pt_regs(), 0);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/* ptrace.c */
	3	/* By Ross Biro 1/23/92 */
	4	/* edited by Linus Torvalds */
	5	/* mangled further by Bob Manson (manson@santafe.edu) */
	6	/* more mutilation by David Mosberger (davidm@azstarnet.com) */
	7
	8	#include <linux/kernel.h>
	9	#include <linux/sched.h>
68db0cf1	10	#include <linux/sched/task_stack.h>
1da177e4 LT	11	#include <linux/mm.h>
1da177e4 LT	12	#include <linux/smp.h>
1da177e4 LT	13	#include <linux/errno.h>
	14	#include <linux/ptrace.h>
	15	#include <linux/user.h>
1da177e4	16	#include <linux/security.h>
7ed20e1a	17	#include <linux/signal.h>
12f79be9	18	#include <linux/tracehook.h>
a9302e84	19	#include <linux/audit.h>
1da177e4	20
7c0f6ba6	21	#include <linux/uaccess.h>
1da177e4	22	#include <asm/pgtable.h>
1da177e4 LT	23	#include <asm/fpu.h>
	24
	25	#include "proto.h"
	26
	27	#define DEBUG DBG_MEM
	28	#undef DEBUG
	29
	30	#ifdef DEBUG
	31	enum {
	32	DBG_MEM = (1<<0),
	33	DBG_BPT = (1<<1),
	34	DBG_MEM_ALL = (1<<2)
	35	};
	36	#define DBG(fac,args) {if ((fac) & DEBUG) printk args;}
	37	#else
	38	#define DBG(fac,args)
	39	#endif
	40
	41	#define BREAKINST 0x00000080 /* call_pal bpt */
	42
	43	/*
	44	* does not yet catch signals sent when the child dies.
	45	* in exit.c or in signal.c.
	46	*/
	47
	48	/*
	49	* Processes always block with the following stack-layout:
	50	*
	51	* +================================+ <---- task + 2*PAGE_SIZE
	52	* \| PALcode saved frame (ps, pc, \| ^
	53	* \| gp, a0, a1, a2) \| \|
	54	* +================================+ \| struct pt_regs
	55	* \| \| \|
	56	* \| frame generated by SAVE_ALL \| \|
	57	* \| \| v
	58	* +================================+
	59	* \| \| ^
	60	* \| frame saved by do_switch_stack \| \| struct switch_stack
	61	* \| \| v
	62	* +================================+
	63	*/
	64
	65	/*
	66	* The following table maps a register index into the stack offset at
	67	* which the register is saved. Register indices are 0-31 for integer
	68	* regs, 32-63 for fp regs, and 64 for the pc. Notice that sp and
	69	* zero have no stack-slot and need to be treated specially (see
	70	* get_reg/put_reg below).
	71	*/
	72	enum {
	73	REG_R0 = 0, REG_F0 = 32, REG_FPCR = 63, REG_PC = 64
	74	};
	75
e52f4ca2	76	#define PT_REG(reg) \
	77	(PAGE_SIZE*2 - sizeof(struct pt_regs) + offsetof(struct pt_regs, reg))
	78
	79	#define SW_REG(reg) \
	80	(PAGE_SIZE*2 - sizeof(struct pt_regs) - sizeof(struct switch_stack) \
	81	+ offsetof(struct switch_stack, reg))
	82
1da177e4 LT	83	static int regoff[] = {
	84	PT_REG( r0), PT_REG( r1), PT_REG( r2), PT_REG( r3),
	85	PT_REG( r4), PT_REG( r5), PT_REG( r6), PT_REG( r7),
	86	PT_REG( r8), SW_REG( r9), SW_REG( r10), SW_REG( r11),
	87	SW_REG( r12), SW_REG( r13), SW_REG( r14), SW_REG( r15),
	88	PT_REG( r16), PT_REG( r17), PT_REG( r18), PT_REG( r19),
	89	PT_REG( r20), PT_REG( r21), PT_REG( r22), PT_REG( r23),
	90	PT_REG( r24), PT_REG( r25), PT_REG( r26), PT_REG( r27),
	91	PT_REG( r28), PT_REG( gp), -1, -1,
	92	SW_REG(fp[ 0]), SW_REG(fp[ 1]), SW_REG(fp[ 2]), SW_REG(fp[ 3]),
	93	SW_REG(fp[ 4]), SW_REG(fp[ 5]), SW_REG(fp[ 6]), SW_REG(fp[ 7]),
	94	SW_REG(fp[ 8]), SW_REG(fp[ 9]), SW_REG(fp[10]), SW_REG(fp[11]),
	95	SW_REG(fp[12]), SW_REG(fp[13]), SW_REG(fp[14]), SW_REG(fp[15]),
	96	SW_REG(fp[16]), SW_REG(fp[17]), SW_REG(fp[18]), SW_REG(fp[19]),
	97	SW_REG(fp[20]), SW_REG(fp[21]), SW_REG(fp[22]), SW_REG(fp[23]),
	98	SW_REG(fp[24]), SW_REG(fp[25]), SW_REG(fp[26]), SW_REG(fp[27]),
	99	SW_REG(fp[28]), SW_REG(fp[29]), SW_REG(fp[30]), SW_REG(fp[31]),
	100	PT_REG( pc)
	101	};
	102
	103	static unsigned long zero;
	104
	105	/*
	106	* Get address of register REGNO in task TASK.
	107	*/
	108	static unsigned long *
	109	get_reg_addr(struct task_struct * task, unsigned long regno)
	110	{
	111	unsigned long *addr;
	112
	113	if (regno == 30) {
37bfbaf9	114	addr = &task_thread_info(task)->pcb.usp;
1da177e4	115	} else if (regno == 65) {
37bfbaf9	116	addr = &task_thread_info(task)->pcb.unique;
1da177e4 LT	117	} else if (regno == 31 \|\| regno > 65) {
	118	zero = 0;
	119	addr = &zero;
	120	} else {
27f45130	121	addr = task_stack_page(task) + regoff[regno];
1da177e4 LT	122	}
	123	return addr;
	124	}
	125
	126	/*
	127	* Get contents of register REGNO in task TASK.
	128	*/
	129	static unsigned long
	130	get_reg(struct task_struct * task, unsigned long regno)
	131	{
	132	/* Special hack for fpcr -- combine hardware and software bits. */
	133	if (regno == 63) {
	134	unsigned long fpcr = *get_reg_addr(task, regno);
	135	unsigned long swcr
37bfbaf9	136	= task_thread_info(task)->ieee_state & IEEE_SW_MASK;
1da177e4 LT	137	swcr = swcr_update_status(swcr, fpcr);
	138	return fpcr \| swcr;
	139	}
	140	return *get_reg_addr(task, regno);
	141	}
	142
	143	/*
	144	* Write contents of register REGNO in task TASK.
	145	*/
	146	static int
	147	put_reg(struct task_struct *task, unsigned long regno, unsigned long data)
	148	{
	149	if (regno == 63) {
37bfbaf9 AV	150	task_thread_info(task)->ieee_state
37bfbaf9 AV	151	= ((task_thread_info(task)->ieee_state & ~IEEE_SW_MASK)
1da177e4 LT	152	\| (data & IEEE_SW_MASK));
	153	data = (data & FPCR_DYN_MASK) \| ieee_swcr_to_fpcr(data);
	154	}
	155	*get_reg_addr(task, regno) = data;
	156	return 0;
	157	}
	158
	159	static inline int
	160	read_int(struct task_struct task, unsigned long addr, int data)
	161	{
f307ab6d LS	162	int copied = access_process_vm(task, addr, data, sizeof(int),
f307ab6d LS	163	FOLL_FORCE);
1da177e4 LT	164	return (copied == sizeof(int)) ? 0 : -EIO;
	165	}
	166
	167	static inline int
	168	write_int(struct task_struct *task, unsigned long addr, int data)
	169	{
f307ab6d LS	170	int copied = access_process_vm(task, addr, &data, sizeof(int),
f307ab6d LS	171	FOLL_FORCE \| FOLL_WRITE);
1da177e4 LT	172	return (copied == sizeof(int)) ? 0 : -EIO;
	173	}
	174
	175	/*
	176	* Set breakpoint.
	177	*/
	178	int
	179	ptrace_set_bpt(struct task_struct * child)
	180	{
	181	int displ, i, res, reg_b, nsaved = 0;
	182	unsigned int insn, op_code;
	183	unsigned long pc;
	184
	185	pc = get_reg(child, REG_PC);
	186	res = read_int(child, pc, (int *) &insn);
	187	if (res < 0)
	188	return res;
	189
	190	op_code = insn >> 26;
	191	if (op_code >= 0x30) {
	192	/*
	193	* It's a branch: instead of trying to figure out
	194	* whether the branch will be taken or not, we'll put
	195	* a breakpoint at either location. This is simpler,
	196	* more reliable, and probably not a whole lot slower
	197	* than the alternative approach of emulating the
	198	* branch (emulation can be tricky for fp branches).
	199	*/
	200	displ = ((s32)(insn << 11)) >> 9;
37bfbaf9	201	task_thread_info(child)->bpt_addr[nsaved++] = pc + 4;
1da177e4	202	if (displ) /* guard against unoptimized code */
37bfbaf9	203	task_thread_info(child)->bpt_addr[nsaved++]
1da177e4 LT	204	= pc + 4 + displ;
	205	DBG(DBG_BPT, ("execing branch\n"));
	206	} else if (op_code == 0x1a) {
	207	reg_b = (insn >> 16) & 0x1f;
37bfbaf9	208	task_thread_info(child)->bpt_addr[nsaved++] = get_reg(child, reg_b);
1da177e4 LT	209	DBG(DBG_BPT, ("execing jump\n"));
1da177e4 LT	210	} else {
37bfbaf9	211	task_thread_info(child)->bpt_addr[nsaved++] = pc + 4;
1da177e4 LT	212	DBG(DBG_BPT, ("execing normal insn\n"));
	213	}
	214
	215	/* install breakpoints: */
	216	for (i = 0; i < nsaved; ++i) {
37bfbaf9	217	res = read_int(child, task_thread_info(child)->bpt_addr[i],
1da177e4 LT	218	(int *) &insn);
	219	if (res < 0)
	220	return res;
37bfbaf9	221	task_thread_info(child)->bpt_insn[i] = insn;
1da177e4	222	DBG(DBG_BPT, (" -> next_pc=%lx\n",
37bfbaf9 AV	223	task_thread_info(child)->bpt_addr[i]));
37bfbaf9 AV	224	res = write_int(child, task_thread_info(child)->bpt_addr[i],
1da177e4 LT	225	BREAKINST);
	226	if (res < 0)
	227	return res;
	228	}
37bfbaf9	229	task_thread_info(child)->bpt_nsaved = nsaved;
1da177e4 LT	230	return 0;
	231	}
	232
	233	/*
	234	* Ensure no single-step breakpoint is pending. Returns non-zero
	235	* value if child was being single-stepped.
	236	*/
	237	int
	238	ptrace_cancel_bpt(struct task_struct * child)
	239	{
37bfbaf9	240	int i, nsaved = task_thread_info(child)->bpt_nsaved;
1da177e4	241
37bfbaf9	242	task_thread_info(child)->bpt_nsaved = 0;
1da177e4 LT	243
	244	if (nsaved > 2) {
	245	printk("ptrace_cancel_bpt: bogus nsaved: %d!\n", nsaved);
	246	nsaved = 2;
	247	}
	248
	249	for (i = 0; i < nsaved; ++i) {
37bfbaf9 AV	250	write_int(child, task_thread_info(child)->bpt_addr[i],
37bfbaf9 AV	251	task_thread_info(child)->bpt_insn[i]);
1da177e4 LT	252	}
	253	return (nsaved != 0);
	254	}
	255
fd341abb CH	256	void user_enable_single_step(struct task_struct *child)
	257	{
	258	/* Mark single stepping. */
	259	task_thread_info(child)->bpt_nsaved = -1;
	260	}
	261
	262	void user_disable_single_step(struct task_struct *child)
	263	{
	264	ptrace_cancel_bpt(child);
	265	}
	266
1da177e4 LT	267	/*
	268	* Called by kernel/ptrace.c when detaching..
	269	*
	270	* Make sure the single step bit is not set.
	271	*/
	272	void ptrace_disable(struct task_struct *child)
	273	{
fd341abb	274	user_disable_single_step(child);
1da177e4 LT	275	}
1da177e4 LT	276
9b05a69e NK	277	long arch_ptrace(struct task_struct *child, long request,
9b05a69e NK	278	unsigned long addr, unsigned long data)
1da177e4	279	{
1da177e4 LT	280	unsigned long tmp;
	281	size_t copied;
	282	long ret;
	283
1da177e4 LT	284	switch (request) {
	285	/* When I and D space are separate, these will need to be fixed. */
	286	case PTRACE_PEEKTEXT: /* read word at location addr. */
	287	case PTRACE_PEEKDATA:
84d77d3f	288	copied = ptrace_access_vm(child, addr, &tmp, sizeof(tmp),
f307ab6d	289	FOLL_FORCE);
1da177e4 LT	290	ret = -EIO;
	291	if (copied != sizeof(tmp))
	292	break;
	293
a5f833f3	294	force_successful_syscall_return();
1da177e4 LT	295	ret = tmp;
	296	break;
	297
	298	/* Read register number ADDR. */
	299	case PTRACE_PEEKUSR:
a5f833f3	300	force_successful_syscall_return();
1da177e4	301	ret = get_reg(child, addr);
9b05a69e	302	DBG(DBG_MEM, ("peek $%lu->%#lx\n", addr, ret));
1da177e4 LT	303	break;
	304
	305	/* When I and D space are separate, this will have to be fixed. */
	306	case PTRACE_POKETEXT: /* write the word at location addr. */
	307	case PTRACE_POKEDATA:
f284ce72	308	ret = generic_ptrace_pokedata(child, addr, data);
1da177e4 LT	309	break;
	310
	311	case PTRACE_POKEUSR: /* write the specified register */
9b05a69e	312	DBG(DBG_MEM, ("poke $%lu<-%#lx\n", addr, data));
1da177e4 LT	313	ret = put_reg(child, addr, data);
1da177e4 LT	314	break;
1da177e4 LT	315	default:
1da177e4 LT	316	ret = ptrace_request(child, request, addr, data);
a5f833f3	317	break;
1da177e4	318	}
1da177e4 LT	319	return ret;
	320	}
	321
12f79be9 AV	322	asmlinkage unsigned long syscall_trace_enter(void)
	323	{
	324	unsigned long ret = 0;
a9302e84	325	struct pt_regs *regs = current_pt_regs();
12f79be9 AV	326	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
	327	tracehook_report_syscall_entry(current_pt_regs()))
	328	ret = -1UL;
91397401	329	audit_syscall_entry(regs->r0, regs->r16, regs->r17, regs->r18, regs->r19);
12f79be9 AV	330	return ret ?: current_pt_regs()->r0;
	331	}
	332
1da177e4	333	asmlinkage void
12f79be9	334	syscall_trace_leave(void)
1da177e4	335	{
a9302e84	336	audit_syscall_exit(current_pt_regs());
12f79be9 AV	337	if (test_thread_flag(TIF_SYSCALL_TRACE))
12f79be9 AV	338	tracehook_report_syscall_exit(current_pt_regs(), 0);
1da177e4	339	}