[mirror_ubuntu-focal-kernel.git] / arch / x86 / um / ptrace_32.c

/*
 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */

#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <asm/ptrace-abi.h>
#include <skas.h>

extern int arch_switch_tls(struct task_struct *to);

void arch_switch_to(struct task_struct *to)
{
	int err = arch_switch_tls(to);
	if (!err)
		return;

	if (err != -EINVAL)
		printk(KERN_WARNING "arch_switch_tls failed, errno %d, "
		       "not EINVAL\n", -err);
	else
		printk(KERN_WARNING "arch_switch_tls failed, errno = EINVAL\n");
}

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),
				FOLL_FORCE);
		if (n != sizeof(instr)) {
			printk(KERN_ERR "is_syscall : failed to read "
			       "instruction from 0x%lx\n", addr);
			return 1;
		}
	}
	/* int 0x80 or sysenter */
	return (instr == 0x80cd) || (instr == 0x340f);
}

/* determines which flags the user has access to. */
/* 1 = access 0 = no access */
#define FLAG_MASK 0x00044dd5

static const int reg_offsets[] = {
	[EBX] = HOST_BX,
	[ECX] = HOST_CX,
	[EDX] = HOST_DX,
	[ESI] = HOST_SI,
	[EDI] = HOST_DI,
	[EBP] = HOST_BP,
	[EAX] = HOST_AX,
	[DS] = HOST_DS,
	[ES] = HOST_ES,
	[FS] = HOST_FS,
	[GS] = HOST_GS,
	[EIP] = HOST_IP,
	[CS] = HOST_CS,
	[EFL] = HOST_EFLAGS,
	[UESP] = HOST_SP,
	[SS] = HOST_SS,
	[ORIG_EAX] = HOST_ORIG_AX,
};

int putreg(struct task_struct *child, int regno, unsigned long value)
{
	regno >>= 2;
	switch (regno) {
	case EBX:
	case ECX:
	case EDX:
	case ESI:
	case EDI:
	case EBP:
	case EAX:
	case EIP:
	case UESP:
		break;
	case ORIG_EAX:
		/* Update the syscall number. */
		UPT_SYSCALL_NR(&child->thread.regs.regs) = value;
		break;
	case FS:
		if (value && (value & 3) != 3)
			return -EIO;
		break;
	case GS:
		if (value && (value & 3) != 3)
			return -EIO;
		break;
	case DS:
	case ES:
		if (value && (value & 3) != 3)
			return -EIO;
		value &= 0xffff;
		break;
	case SS:
	case CS:
		if ((value & 3) != 3)
			return -EIO;
		value &= 0xffff;
		break;
	case EFL:
		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]] = 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;

	regno >>= 2;
	switch (regno) {
	case FS:
	case GS:
	case DS:
	case ES:
	case SS:
	case CS:
		mask = 0xffff;
		break;
	case EIP:
	case UESP:
	case EAX:
	case EBX:
	case ECX:
	case EDX:
	case ESI:
	case EDI:
	case EBP:
	case EFL:
	case ORIG_EAX:
		break;
	default:
		panic("Bad register in getreg() : %d\n", regno);
	}
	return mask & child->thread.regs.regs.gp[reg_offsets[regno]];
}

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

static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
{
	int err, n, cpu = task_cpu(child);
	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 = task_cpu(child);
	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);
}

static int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
{
	int err, n, cpu = task_cpu(child);
	struct user_fxsr_struct fpregs;

	err = save_fpx_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_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
{
	int n, cpu = task_cpu(child);
	struct user_fxsr_struct fpregs;

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

	return restore_fpx_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_GETFPXREGS: /* Get the child FPU state. */
		ret = get_fpxregs(datap, child);
		break;
	case PTRACE_SETFPXREGS: /* Set the child FPU state. */
		ret = set_fpxregs(datap, child);
		break;
	default:
		ret = -EIO;
	}
	return ret;
}
Commit	Line	Data
ba180fd4 JD	1	/*
ba180fd4 JD	2	* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
1da177e4 LT	3	* Licensed under the GPL
	4	*/
	5
37185b33 AV	6	#include <linux/mm.h>
37185b33 AV	7	#include <linux/sched.h>
7c0f6ba6	8	#include <linux/uaccess.h>
da028d5e	9	#include <asm/ptrace-abi.h>
37185b33	10	#include <skas.h>
1da177e4	11
291248fd	12	extern int arch_switch_tls(struct task_struct *to);
77bf4400	13
291248fd	14	void arch_switch_to(struct task_struct *to)
1da177e4	15	{
291248fd	16	int err = arch_switch_tls(to);
54d8d3b5 PBG	17	if (!err)
	18	return;
	19
	20	if (err != -EINVAL)
ba180fd4 JD	21	printk(KERN_WARNING "arch_switch_tls failed, errno %d, "
ba180fd4 JD	22	"not EINVAL\n", -err);
54d8d3b5	23	else
77bf4400	24	printk(KERN_WARNING "arch_switch_tls failed, errno = EINVAL\n");
1da177e4 LT	25	}
	26
	27	int is_syscall(unsigned long addr)
	28	{
	29	unsigned short instr;
	30	int n;
	31
	32	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
ba180fd4	33	if (n) {
81efcd33 BS	34	/* access_process_vm() grants access to vsyscall and stub,
	35	* while copy_from_user doesn't. Maybe access_process_vm is
	36	* slow, but that doesn't matter, since it will be called only
	37	* in case of singlestepping, if copy_from_user failed.
	38	*/
f307ab6d LS	39	n = access_process_vm(current, addr, &instr, sizeof(instr),
f307ab6d LS	40	FOLL_FORCE);
ba180fd4 JD	41	if (n != sizeof(instr)) {
	42	printk(KERN_ERR "is_syscall : failed to read "
	43	"instruction from 0x%lx\n", addr);
	44	return 1;
81efcd33	45	}
1da177e4 LT	46	}
1da177e4 LT	47	/* int 0x80 or sysenter */
ba180fd4	48	return (instr == 0x80cd) \|\| (instr == 0x340f);
1da177e4 LT	49	}
	50
	51	/* determines which flags the user has access to. */
	52	/* 1 = access 0 = no access */
	53	#define FLAG_MASK 0x00044dd5
	54
412f90ed	55	static const int reg_offsets[] = {
3579a389 AV	56	[EBX] = HOST_BX,
	57	[ECX] = HOST_CX,
	58	[EDX] = HOST_DX,
	59	[ESI] = HOST_SI,
	60	[EDI] = HOST_DI,
	61	[EBP] = HOST_BP,
	62	[EAX] = HOST_AX,
412f90ed AV	63	[DS] = HOST_DS,
	64	[ES] = HOST_ES,
	65	[FS] = HOST_FS,
	66	[GS] = HOST_GS,
	67	[EIP] = HOST_IP,
	68	[CS] = HOST_CS,
	69	[EFL] = HOST_EFLAGS,
	70	[UESP] = HOST_SP,
	71	[SS] = HOST_SS,
e04c989e	72	[ORIG_EAX] = HOST_ORIG_AX,
412f90ed AV	73	};
412f90ed AV	74
1da177e4 LT	75	int putreg(struct task_struct *child, int regno, unsigned long value)
	76	{
	77	regno >>= 2;
	78	switch (regno) {
412f90ed AV	79	case EBX:
	80	case ECX:
	81	case EDX:
	82	case ESI:
	83	case EDI:
	84	case EBP:
	85	case EAX:
	86	case EIP:
	87	case UESP:
ce29856a	88	break;
e04c989e	89	case ORIG_EAX:
ce29856a MS	90	/* Update the syscall number. */
ce29856a MS	91	UPT_SYSCALL_NR(&child->thread.regs.regs) = value;
412f90ed	92	break;
1da177e4 LT	93	case FS:
	94	if (value && (value & 3) != 3)
	95	return -EIO;
412f90ed	96	break;
1da177e4 LT	97	case GS:
	98	if (value && (value & 3) != 3)
	99	return -EIO;
412f90ed	100	break;
1da177e4 LT	101	case DS:
	102	case ES:
	103	if (value && (value & 3) != 3)
	104	return -EIO;
	105	value &= 0xffff;
	106	break;
	107	case SS:
	108	case CS:
	109	if ((value & 3) != 3)
	110	return -EIO;
	111	value &= 0xffff;
	112	break;
	113	case EFL:
	114	value &= FLAG_MASK;
412f90ed AV	115	child->thread.regs.regs.gp[HOST_EFLAGS] \|= value;
412f90ed AV	116	return 0;
412f90ed AV	117	default :
412f90ed AV	118	panic("Bad register in putreg() : %d\n", regno);
1da177e4	119	}
412f90ed	120	child->thread.regs.regs.gp[reg_offsets[regno]] = value;
1da177e4 LT	121	return 0;
	122	}
	123
82c1c11b BS	124	int poke_user(struct task_struct *child, long addr, long data)
82c1c11b BS	125	{
ba180fd4 JD	126	if ((addr & 3) \|\| addr < 0)
	127	return -EIO;
	128
	129	if (addr < MAX_REG_OFFSET)
	130	return putreg(child, addr, data);
	131	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
	132	(addr <= offsetof(struct user, u_debugreg[7]))) {
	133	addr -= offsetof(struct user, u_debugreg[0]);
	134	addr = addr >> 2;
	135	if ((addr == 4) \|\| (addr == 5))
	136	return -EIO;
	137	child->thread.arch.debugregs[addr] = data;
	138	return 0;
	139	}
	140	return -EIO;
82c1c11b BS	141	}
82c1c11b BS	142
1da177e4 LT	143	unsigned long getreg(struct task_struct *child, int regno)
1da177e4 LT	144	{
412f90ed	145	unsigned long mask = ~0UL;
1da177e4 LT	146
	147	regno >>= 2;
	148	switch (regno) {
	149	case FS:
	150	case GS:
	151	case DS:
	152	case ES:
	153	case SS:
	154	case CS:
412f90ed AV	155	mask = 0xffff;
	156	break;
	157	case EIP:
	158	case UESP:
	159	case EAX:
	160	case EBX:
	161	case ECX:
	162	case EDX:
	163	case ESI:
	164	case EDI:
	165	case EBP:
	166	case EFL:
e04c989e	167	case ORIG_EAX:
412f90ed	168	break;
1da177e4	169	default:
412f90ed	170	panic("Bad register in getreg() : %d\n", regno);
1da177e4	171	}
412f90ed	172	return mask & child->thread.regs.regs.gp[reg_offsets[regno]];
1da177e4 LT	173	}
1da177e4 LT	174
ba180fd4	175	/* read the word at location addr in the USER area. */
82c1c11b BS	176	int peek_user(struct task_struct *child, long addr, long data)
82c1c11b BS	177	{
4d338e1a	178	unsigned long tmp;
82c1c11b	179
4d338e1a AV	180	if ((addr & 3) \|\| addr < 0)
4d338e1a AV	181	return -EIO;
82c1c11b	182
4d338e1a	183	tmp = 0; /* Default return condition */
ba180fd4	184	if (addr < MAX_REG_OFFSET) {
4d338e1a AV	185	tmp = getreg(child, addr);
4d338e1a AV	186	}
ba180fd4 JD	187	else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
ba180fd4 JD	188	(addr <= offsetof(struct user, u_debugreg[7]))) {
4d338e1a AV	189	addr -= offsetof(struct user, u_debugreg[0]);
	190	addr = addr >> 2;
	191	tmp = child->thread.arch.debugregs[addr];
	192	}
	193	return put_user(tmp, (unsigned long __user *) data);
82c1c11b BS	194	}
82c1c11b BS	195
f2833aef	196	static int get_fpregs(struct user_i387_struct __user buf, struct task_struct child)
1da177e4	197	{
d896fa20	198	int err, n, cpu = task_cpu(child);
47906dd9	199	struct user_i387_struct fpregs;
1da177e4	200
a78ff111 EC	201	err = save_i387_registers(userspace_pid[cpu],
a78ff111 EC	202	(unsigned long *) &fpregs);
e8012b58 JD	203	if (err)
	204	return err;
	205
47906dd9	206	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
e8012b58 JD	207	if(n > 0)
	208	return -EFAULT;
	209
	210	return n;
1da177e4 LT	211	}
1da177e4 LT	212
f2833aef	213	static int set_fpregs(struct user_i387_struct __user buf, struct task_struct child)
1da177e4	214	{
d896fa20	215	int n, cpu = task_cpu(child);
47906dd9	216	struct user_i387_struct fpregs;
1da177e4	217
47906dd9	218	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
e8012b58	219	if (n > 0)
ba180fd4	220	return -EFAULT;
e8012b58	221
a78ff111	222	return restore_i387_registers(userspace_pid[cpu],
47906dd9	223	(unsigned long *) &fpregs);
1da177e4 LT	224	}
1da177e4 LT	225
f2833aef	226	static int get_fpxregs(struct user_fxsr_struct __user buf, struct task_struct child)
1da177e4	227	{
d896fa20	228	int err, n, cpu = task_cpu(child);
47906dd9	229	struct user_fxsr_struct fpregs;
1da177e4	230
47906dd9	231	err = save_fpx_registers(userspace_pid[cpu], (unsigned long *) &fpregs);
ba180fd4	232	if (err)
e8012b58 JD	233	return err;
e8012b58 JD	234
47906dd9	235	n = copy_to_user(buf, &fpregs, sizeof(fpregs));
e8012b58	236	if(n > 0)
ba180fd4	237	return -EFAULT;
1da177e4	238
e8012b58	239	return n;
1da177e4 LT	240	}
1da177e4 LT	241
f2833aef	242	static int set_fpxregs(struct user_fxsr_struct __user buf, struct task_struct child)
1da177e4	243	{
d896fa20	244	int n, cpu = task_cpu(child);
47906dd9	245	struct user_fxsr_struct fpregs;
e8012b58	246
47906dd9	247	n = copy_from_user(&fpregs, buf, sizeof(fpregs));
e8012b58 JD	248	if (n > 0)
	249	return -EFAULT;
	250
47906dd9 JD	251	return restore_fpx_registers(userspace_pid[cpu],
47906dd9 JD	252	(unsigned long *) &fpregs);
1da177e4 LT	253	}
1da177e4 LT	254
9b05a69e NK	255	long subarch_ptrace(struct task_struct *child, long request,
9b05a69e NK	256	unsigned long addr, unsigned long data)
e8012b58	257	{
01599cdc AV	258	int ret = -EIO;
01599cdc AV	259	void __user datap = (void __user ) data;
01599cdc	260	switch (request) {
f2833aef AV	261	case PTRACE_GETFPREGS: /* Get the child FPU state. */
	262	ret = get_fpregs(datap, child);
	263	break;
	264	case PTRACE_SETFPREGS: /* Set the child FPU state. */
	265	ret = set_fpregs(datap, child);
	266	break;
01599cdc AV	267	case PTRACE_GETFPXREGS: /* Get the child FPU state. */
	268	ret = get_fpxregs(datap, child);
	269	break;
	270	case PTRACE_SETFPXREGS: /* Set the child FPU state. */
	271	ret = set_fpxregs(datap, child);
	272	break;
f2833aef AV	273	default:
f2833aef AV	274	ret = -EIO;
01599cdc	275	}
01599cdc	276	return ret;
e8012b58	277	}