[mirror_ubuntu-focal-kernel.git] / arch / x86 / um / ptrace_64.c

/*
 * Copyright 2003 PathScale, Inc.
 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 *
 * Licensed under the GPL
 */

#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/errno.h>
#define __FRAME_OFFSETS
#include <asm/ptrace.h>
#include <asm/uaccess.h>
#include <asm/ptrace-abi.h>

/*
 * determines which flags the user has access to.
 * 1 = access 0 = no access
 */
#define FLAG_MASK 0x44dd5UL

static const int reg_offsets[] =
{
	[R8 >> 3] = HOST_R8,
	[R9 >> 3] = HOST_R9,
	[R10 >> 3] = HOST_R10,
	[R11 >> 3] = HOST_R11,
	[R12 >> 3] = HOST_R12,
	[R13 >> 3] = HOST_R13,
	[R14 >> 3] = HOST_R14,
	[R15 >> 3] = HOST_R15,
	[RIP >> 3] = HOST_IP,
	[RSP >> 3] = HOST_SP,
	[RAX >> 3] = HOST_AX,
	[RBX >> 3] = HOST_BX,
	[RCX >> 3] = HOST_CX,
	[RDX >> 3] = HOST_DX,
	[RSI >> 3] = HOST_SI,
	[RDI >> 3] = HOST_DI,
	[RBP >> 3] = HOST_BP,
	[CS >> 3] = HOST_CS,
	[SS >> 3] = HOST_SS,
	[FS_BASE >> 3] = HOST_FS_BASE,
	[GS_BASE >> 3] = HOST_GS_BASE,
	[DS >> 3] = HOST_DS,
	[ES >> 3] = HOST_ES,
	[FS >> 3] = HOST_FS,
	[GS >> 3] = HOST_GS,
	[EFLAGS >> 3] = HOST_EFLAGS,
	[ORIG_RAX >> 3] = HOST_ORIG_AX,
};

int putreg(struct task_struct *child, int regno, unsigned long value)
{
#ifdef TIF_IA32
	/*
	 * Some code in the 64bit emulation may not be 64bit clean.
	 * Don't take any chances.
	 */
	if (test_tsk_thread_flag(child, TIF_IA32))
		value &= 0xffffffff;
#endif
	switch (regno) {
	case R8:
	case R9:
	case R10:
	case R11:
	case R12:
	case R13:
	case R14:
	case R15:
	case RIP:
	case RSP:
	case RAX:
	case RBX:
	case RCX:
	case RDX:
	case RSI:
	case RDI:
	case RBP:
	case ORIG_RAX:
		break;

	case FS:
	case GS:
	case DS:
	case ES:
	case SS:
	case CS:
		if (value && (value & 3) != 3)
			return -EIO;
		value &= 0xffff;
		break;

	case FS_BASE:
	case GS_BASE:
		if (!((value >> 48) == 0 || (value >> 48) == 0xffff))
			return -EIO;
		break;

	case EFLAGS:
		value &= FLAG_MASK;
		child->thread.regs.regs.gp[HOST_EFLAGS] |= value;
		return 0;

	default:
		panic("Bad register in putreg(): %d\n", regno);
	}

	child->thread.regs.regs.gp[reg_offsets[regno >> 3]] = value;
	return 0;
}

int poke_user(struct task_struct *child, long addr, long data)
{
	if ((addr & 3) || addr < 0)
		return -EIO;

	if (addr < MAX_REG_OFFSET)
		return putreg(child, addr, data);
	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
		(addr <= offsetof(struct user, u_debugreg[7]))) {
		addr -= offsetof(struct user, u_debugreg[0]);
		addr = addr >> 2;
		if ((addr == 4) || (addr == 5))
			return -EIO;
		child->thread.arch.debugregs[addr] = data;
		return 0;
	}
	return -EIO;
}

unsigned long getreg(struct task_struct *child, int regno)
{
	unsigned long mask = ~0UL;
#ifdef TIF_IA32
	if (test_tsk_thread_flag(child, TIF_IA32))
		mask = 0xffffffff;
#endif
	switch (regno) {
	case R8:
	case R9:
	case R10:
	case R11:
	case R12:
	case R13:
	case R14:
	case R15:
	case RIP:
	case RSP:
	case RAX:
	case RBX:
	case RCX:
	case RDX:
	case RSI:
	case RDI:
	case RBP:
	case ORIG_RAX:
	case EFLAGS:
	case FS_BASE:
	case GS_BASE:
		break;
	case FS:
	case GS:
	case DS:
	case ES:
	case SS:
	case CS:
		mask = 0xffff;
		break;
	default:
		panic("Bad register in getreg: %d\n", regno);
	}
	return mask & child->thread.regs.regs.gp[reg_offsets[regno >> 3]];
}

int peek_user(struct task_struct *child, long addr, long data)
{
	/* read the word at location addr in the USER area. */
	unsigned long tmp;

	if ((addr & 3) || addr < 0)
		return -EIO;

	tmp = 0;  /* Default return condition */
	if (addr < MAX_REG_OFFSET)
		tmp = getreg(child, addr);
	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
		(addr <= offsetof(struct user, u_debugreg[7]))) {
		addr -= offsetof(struct user, u_debugreg[0]);
		addr = addr >> 2;
		tmp = child->thread.arch.debugregs[addr];
	}
	return put_user(tmp, (unsigned long *) data);
}

/* XXX Mostly copied from sys-i386 */
int is_syscall(unsigned long addr)
{
	unsigned short instr;
	int n;

	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
	if (n) {
		/*
		 * access_process_vm() grants access to vsyscall and stub,
		 * while copy_from_user doesn't. Maybe access_process_vm is
		 * slow, but that doesn't matter, since it will be called only
		 * in case of singlestepping, if copy_from_user failed.
		 */
		n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
		if (n != sizeof(instr)) {
			printk("is_syscall : failed to read instruction from "
			       "0x%lx\n", addr);
			return 1;
		}
	}
	/* sysenter */
	return instr == 0x050f;
}

static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
	struct user_i387_struct fpregs;

	err = save_i387_registers(userspace_pid[cpu],
				  (unsigned long *) &fpregs);
	if (err)
		return err;

	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
	if (n > 0)
		return -EFAULT;

	return n;
}

static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
	int n, cpu = ((struct thread_info *) child->stack)->cpu;
	struct user_i387_struct fpregs;

	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
	if (n > 0)
		return -EFAULT;

	return restore_i387_registers(userspace_pid[cpu],
				      (unsigned long *) &fpregs);
}

long subarch_ptrace(struct task_struct *child, long request,
		    unsigned long addr, unsigned long data)
{
	int ret = -EIO;
	void __user *datap = (void __user *) data;

	switch (request) {
	case PTRACE_GETFPREGS: /* Get the child FPU state. */
		ret = get_fpregs(datap, child);
		break;
	case PTRACE_SETFPREGS: /* Set the child FPU state. */
		ret = set_fpregs(datap, child);
		break;
	case PTRACE_ARCH_PRCTL:
		/* XXX Calls ptrace on the host - needs some SMP thinking */
		ret = arch_prctl(child, data, (void __user *) addr);
		break;
	}

	return ret;
}
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* Copyright 2003 PathScale, Inc.
f0c4cad9	3	* Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
1da177e4 LT	4	*
	5	* Licensed under the GPL
	6	*/
	7
95906b24	8	#include <linux/mm.h>
ba9950c8 JD	9	#include <linux/sched.h>
ba9950c8 JD	10	#include <linux/errno.h>
95906b24 JD	11	#define __FRAME_OFFSETS
95906b24 JD	12	#include <asm/ptrace.h>
ba9950c8	13	#include <asm/uaccess.h>
da028d5e	14	#include <asm/ptrace-abi.h>
1da177e4	15
f0c4cad9 JD	16	/*
	17	* determines which flags the user has access to.
	18	* 1 = access 0 = no access
	19	*/
1da177e4 LT	20	#define FLAG_MASK 0x44dd5UL
1da177e4 LT	21
412f90ed	22	static const int reg_offsets[] =
1da177e4	23	{
412f90ed AV	24	[R8 >> 3] = HOST_R8,
	25	[R9 >> 3] = HOST_R9,
	26	[R10 >> 3] = HOST_R10,
	27	[R11 >> 3] = HOST_R11,
	28	[R12 >> 3] = HOST_R12,
	29	[R13 >> 3] = HOST_R13,
	30	[R14 >> 3] = HOST_R14,
	31	[R15 >> 3] = HOST_R15,
	32	[RIP >> 3] = HOST_IP,
	33	[RSP >> 3] = HOST_SP,
3579a389 AV	34	[RAX >> 3] = HOST_AX,
	35	[RBX >> 3] = HOST_BX,
	36	[RCX >> 3] = HOST_CX,
	37	[RDX >> 3] = HOST_DX,
	38	[RSI >> 3] = HOST_SI,
	39	[RDI >> 3] = HOST_DI,
	40	[RBP >> 3] = HOST_BP,
412f90ed AV	41	[CS >> 3] = HOST_CS,
	42	[SS >> 3] = HOST_SS,
	43	[FS_BASE >> 3] = HOST_FS_BASE,
	44	[GS_BASE >> 3] = HOST_GS_BASE,
	45	[DS >> 3] = HOST_DS,
	46	[ES >> 3] = HOST_ES,
	47	[FS >> 3] = HOST_FS,
	48	[GS >> 3] = HOST_GS,
	49	[EFLAGS >> 3] = HOST_EFLAGS,
966e803a	50	[ORIG_RAX >> 3] = HOST_ORIG_AX,
412f90ed	51	};
1da177e4	52
412f90ed AV	53	int putreg(struct task_struct *child, int regno, unsigned long value)
412f90ed AV	54	{
1da177e4	55	#ifdef TIF_IA32
95906b24 JD	56	/*
	57	* Some code in the 64bit emulation may not be 64bit clean.
	58	* Don't take any chances.
	59	*/
1da177e4 LT	60	if (test_tsk_thread_flag(child, TIF_IA32))
	61	value &= 0xffffffff;
	62	#endif
95906b24	63	switch (regno) {
412f90ed AV	64	case R8:
	65	case R9:
	66	case R10:
	67	case R11:
	68	case R12:
	69	case R13:
	70	case R14:
	71	case R15:
	72	case RIP:
	73	case RSP:
	74	case RAX:
	75	case RBX:
	76	case RCX:
	77	case RDX:
	78	case RSI:
	79	case RDI:
	80	case RBP:
	81	case ORIG_RAX:
	82	break;
	83
1da177e4 LT	84	case FS:
	85	case GS:
	86	case DS:
	87	case ES:
	88	case SS:
	89	case CS:
	90	if (value && (value & 3) != 3)
	91	return -EIO;
	92	value &= 0xffff;
	93	break;
	94
	95	case FS_BASE:
	96	case GS_BASE:
	97	if (!((value >> 48) == 0 \|\| (value >> 48) == 0xffff))
	98	return -EIO;
	99	break;
	100
	101	case EFLAGS:
	102	value &= FLAG_MASK;
412f90ed AV	103	child->thread.regs.regs.gp[HOST_EFLAGS] \|= value;
	104	return 0;
	105
	106	default:
	107	panic("Bad register in putreg(): %d\n", regno);
1da177e4 LT	108	}
1da177e4 LT	109
412f90ed	110	child->thread.regs.regs.gp[reg_offsets[regno >> 3]] = value;
1da177e4 LT	111	return 0;
	112	}
	113
82c1c11b BS	114	int poke_user(struct task_struct *child, long addr, long data)
82c1c11b BS	115	{
f0c4cad9 JD	116	if ((addr & 3) \|\| addr < 0)
	117	return -EIO;
	118
	119	if (addr < MAX_REG_OFFSET)
	120	return putreg(child, addr, data);
	121	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
95906b24	122	(addr <= offsetof(struct user, u_debugreg[7]))) {
f0c4cad9 JD	123	addr -= offsetof(struct user, u_debugreg[0]);
	124	addr = addr >> 2;
	125	if ((addr == 4) \|\| (addr == 5))
	126	return -EIO;
	127	child->thread.arch.debugregs[addr] = data;
	128	return 0;
	129	}
	130	return -EIO;
82c1c11b BS	131	}
82c1c11b BS	132
1da177e4 LT	133	unsigned long getreg(struct task_struct *child, int regno)
1da177e4 LT	134	{
412f90ed AV	135	unsigned long mask = ~0UL;
	136	#ifdef TIF_IA32
	137	if (test_tsk_thread_flag(child, TIF_IA32))
	138	mask = 0xffffffff;
	139	#endif
1da177e4	140	switch (regno) {
412f90ed AV	141	case R8:
	142	case R9:
	143	case R10:
	144	case R11:
	145	case R12:
	146	case R13:
	147	case R14:
	148	case R15:
	149	case RIP:
	150	case RSP:
	151	case RAX:
	152	case RBX:
	153	case RCX:
	154	case RDX:
	155	case RSI:
	156	case RDI:
	157	case RBP:
	158	case ORIG_RAX:
	159	case EFLAGS:
	160	case FS_BASE:
	161	case GS_BASE:
	162	break;
1da177e4 LT	163	case FS:
	164	case GS:
	165	case DS:
	166	case ES:
	167	case SS:
	168	case CS:
412f90ed AV	169	mask = 0xffff;
412f90ed AV	170	break;
1da177e4	171	default:
412f90ed	172	panic("Bad register in getreg: %d\n", regno);
1da177e4	173	}
412f90ed	174	return mask & child->thread.regs.regs.gp[reg_offsets[regno >> 3]];
1da177e4 LT	175	}
1da177e4 LT	176
82c1c11b BS	177	int peek_user(struct task_struct *child, long addr, long data)
	178	{
	179	/* read the word at location addr in the USER area. */
f0c4cad9	180	unsigned long tmp;
82c1c11b	181
f0c4cad9 JD	182	if ((addr & 3) \|\| addr < 0)
	183	return -EIO;
	184
	185	tmp = 0; /* Default return condition */
95906b24	186	if (addr < MAX_REG_OFFSET)
f0c4cad9	187	tmp = getreg(child, addr);
f0c4cad9	188	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
95906b24	189	(addr <= offsetof(struct user, u_debugreg[7]))) {
f0c4cad9 JD	190	addr -= offsetof(struct user, u_debugreg[0]);
	191	addr = addr >> 2;
	192	tmp = child->thread.arch.debugregs[addr];
	193	}
	194	return put_user(tmp, (unsigned long *) data);
1da177e4 LT	195	}
1da177e4 LT	196
81efcd33	197	/* XXX Mostly copied from sys-i386 */
1da177e4 LT	198	int is_syscall(unsigned long addr)
1da177e4 LT	199	{
81efcd33 BS	200	unsigned short instr;
	201	int n;
	202
	203	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
95906b24 JD	204	if (n) {
	205	/*
	206	* access_process_vm() grants access to vsyscall and stub,
81efcd33 BS	207	* while copy_from_user doesn't. Maybe access_process_vm is
	208	* slow, but that doesn't matter, since it will be called only
	209	* in case of singlestepping, if copy_from_user failed.
	210	*/
	211	n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
f0c4cad9	212	if (n != sizeof(instr)) {
81efcd33 BS	213	printk("is_syscall : failed to read instruction from "
81efcd33 BS	214	"0x%lx\n", addr);
f0c4cad9	215	return 1;
81efcd33 BS	216	}
	217	}
	218	/* sysenter */
f0c4cad9	219	return instr == 0x050f;
1da177e4 LT	220	}
1da177e4 LT	221
f2833aef	222	static int get_fpregs(struct user_i387_struct __user buf, struct task_struct child)
1da177e4	223	{
e8012b58	224	int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
a78ff111	225	struct user_i387_struct fpregs;
1da177e4	226
a78ff111 EC	227	err = save_i387_registers(userspace_pid[cpu],
a78ff111 EC	228	(unsigned long *) &fpregs);
e8012b58 JD	229	if (err)
	230	return err;
	231
a78ff111	232	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
95906b24	233	if (n > 0)
e8012b58 JD	234	return -EFAULT;
	235
	236	return n;
1da177e4 LT	237	}
1da177e4 LT	238
f2833aef	239	static int set_fpregs(struct user_i387_struct __user buf, struct task_struct child)
1da177e4	240	{
e8012b58	241	int n, cpu = ((struct thread_info *) child->stack)->cpu;
a78ff111	242	struct user_i387_struct fpregs;
e8012b58	243
a78ff111	244	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
e8012b58 JD	245	if (n > 0)
	246	return -EFAULT;
	247
a78ff111 EC	248	return restore_i387_registers(userspace_pid[cpu],
a78ff111 EC	249	(unsigned long *) &fpregs);
1da177e4 LT	250	}
1da177e4 LT	251
9b05a69e NK	252	long subarch_ptrace(struct task_struct *child, long request,
9b05a69e NK	253	unsigned long addr, unsigned long data)
1da177e4	254	{
f2833aef AV	255	int ret = -EIO;
	256	void __user datap = (void __user ) data;
	257
	258	switch (request) {
	259	case PTRACE_GETFPREGS: /* Get the child FPU state. */
	260	ret = get_fpregs(datap, child);
	261	break;
	262	case PTRACE_SETFPREGS: /* Set the child FPU state. */
	263	ret = set_fpregs(datap, child);
	264	break;
	265	case PTRACE_ARCH_PRCTL:
	266	/* XXX Calls ptrace on the host - needs some SMP thinking */
	267	ret = arch_prctl(child, data, (void __user *) addr);
	268	break;
	269	}
	270
	271	return ret;
1da177e4	272	}