[mirror_ubuntu-bionic-kernel.git] / arch / x86 / um / signal.c

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


#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/kernel.h>
#include <asm/unistd.h>
#include <asm/uaccess.h>
#include <asm/ucontext.h>
#include "frame_kern.h"
#include "skas.h"

#ifdef CONFIG_X86_32

/*
 * FPU tag word conversions.
 */

static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
{
	unsigned int tmp; /* to avoid 16 bit prefixes in the code */

	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
	tmp = ~twd;
	tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
	/* and move the valid bits to the lower byte. */
	tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
	tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
	tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
	return tmp;
}

static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
{
	struct _fpxreg *st = NULL;
	unsigned long twd = (unsigned long) fxsave->twd;
	unsigned long tag;
	unsigned long ret = 0xffff0000;
	int i;

#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16)

	for (i = 0; i < 8; i++) {
		if (twd & 0x1) {
			st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);

			switch (st->exponent & 0x7fff) {
			case 0x7fff:
				tag = 2;		/* Special */
				break;
			case 0x0000:
				if ( !st->significand[0] &&
				     !st->significand[1] &&
				     !st->significand[2] &&
				     !st->significand[3] ) {
					tag = 1;	/* Zero */
				} else {
					tag = 2;	/* Special */
				}
				break;
			default:
				if (st->significand[3] & 0x8000) {
					tag = 0;	/* Valid */
				} else {
					tag = 2;	/* Special */
				}
				break;
			}
		} else {
			tag = 3;			/* Empty */
		}
		ret |= (tag << (2 * i));
		twd = twd >> 1;
	}
	return ret;
}

static int convert_fxsr_to_user(struct _fpstate __user *buf,
				struct user_fxsr_struct *fxsave)
{
	unsigned long env[7];
	struct _fpreg __user *to;
	struct _fpxreg *from;
	int i;

	env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
	env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
	env[2] = twd_fxsr_to_i387(fxsave);
	env[3] = fxsave->fip;
	env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
	env[5] = fxsave->foo;
	env[6] = fxsave->fos;

	if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
		return 1;

	to = &buf->_st[0];
	from = (struct _fpxreg *) &fxsave->st_space[0];
	for (i = 0; i < 8; i++, to++, from++) {
		unsigned long __user *t = (unsigned long __user *)to;
		unsigned long *f = (unsigned long *)from;

		if (__put_user(*f, t) ||
				__put_user(*(f + 1), t + 1) ||
				__put_user(from->exponent, &to->exponent))
			return 1;
	}
	return 0;
}

static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
				  struct _fpstate __user *buf)
{
	unsigned long env[7];
	struct _fpxreg *to;
	struct _fpreg __user *from;
	int i;

	if (copy_from_user( env, buf, 7 * sizeof(long)))
		return 1;

	fxsave->cwd = (unsigned short)(env[0] & 0xffff);
	fxsave->swd = (unsigned short)(env[1] & 0xffff);
	fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
	fxsave->fip = env[3];
	fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
	fxsave->fcs = (env[4] & 0xffff);
	fxsave->foo = env[5];
	fxsave->fos = env[6];

	to = (struct _fpxreg *) &fxsave->st_space[0];
	from = &buf->_st[0];
	for (i = 0; i < 8; i++, to++, from++) {
		unsigned long *t = (unsigned long *)to;
		unsigned long __user *f = (unsigned long __user *)from;

		if (__get_user(*t, f) ||
		    __get_user(*(t + 1), f + 1) ||
		    __get_user(to->exponent, &from->exponent))
			return 1;
	}
	return 0;
}

extern int have_fpx_regs;

#endif

static int copy_sc_from_user(struct pt_regs *regs,
			     struct sigcontext __user *from)
{
	struct sigcontext sc;
	int err, pid;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	err = copy_from_user(&sc, from, sizeof(sc));
	if (err)
		return err;

#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname

#ifdef CONFIG_X86_32
	GETREG(GS, gs);
	GETREG(FS, fs);
	GETREG(ES, es);
	GETREG(DS, ds);
#endif
	GETREG(DI, di);
	GETREG(SI, si);
	GETREG(BP, bp);
	GETREG(SP, sp);
	GETREG(BX, bx);
	GETREG(DX, dx);
	GETREG(CX, cx);
	GETREG(AX, ax);
	GETREG(IP, ip);

#ifdef CONFIG_X86_64
	GETREG(R8, r8);
	GETREG(R9, r9);
	GETREG(R10, r10);
	GETREG(R11, r11);
	GETREG(R12, r12);
	GETREG(R13, r13);
	GETREG(R14, r14);
	GETREG(R15, r15);
#endif

	GETREG(CS, cs);
	GETREG(EFLAGS, flags);
#ifdef CONFIG_X86_32
	GETREG(SS, ss);
#endif

#undef GETREG

	pid = userspace_pid[current_thread_info()->cpu];
#ifdef CONFIG_X86_32
	if (have_fpx_regs) {
		struct user_fxsr_struct fpx;

		err = copy_from_user(&fpx,
			&((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
				     sizeof(struct user_fxsr_struct));
		if (err)
			return 1;

		err = convert_fxsr_from_user(&fpx, sc.fpstate);
		if (err)
			return 1;

		err = restore_fpx_registers(pid, (unsigned long *) &fpx);
		if (err < 0) {
			printk(KERN_ERR "copy_sc_from_user - "
			       "restore_fpx_registers failed, errno = %d\n",
			       -err);
			return 1;
		}
	} else
#endif
	{
		struct user_i387_struct fp;

		err = copy_from_user(&fp, sc.fpstate,
				     sizeof(struct user_i387_struct));
		if (err)
			return 1;

		err = restore_fp_registers(pid, (unsigned long *) &fp);
		if (err < 0) {
			printk(KERN_ERR "copy_sc_from_user - "
			       "restore_fp_registers failed, errno = %d\n",
			       -err);
			return 1;
		}
	}
	return 0;
}

static int copy_sc_to_user(struct sigcontext __user *to,
			   struct _fpstate __user *to_fp, struct pt_regs *regs,
			   unsigned long mask)
{
	struct sigcontext sc;
	struct faultinfo * fi = &current->thread.arch.faultinfo;
	int err, pid;
	memset(&sc, 0, sizeof(struct sigcontext));

#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]

#ifdef CONFIG_X86_32
	PUTREG(GS, gs);
	PUTREG(FS, fs);
	PUTREG(ES, es);
	PUTREG(DS, ds);
#endif
	PUTREG(DI, di);
	PUTREG(SI, si);
	PUTREG(BP, bp);
	PUTREG(SP, sp);
	PUTREG(BX, bx);
	PUTREG(DX, dx);
	PUTREG(CX, cx);
	PUTREG(AX, ax);
#ifdef CONFIG_X86_64
	PUTREG(R8, r8);
	PUTREG(R9, r9);
	PUTREG(R10, r10);
	PUTREG(R11, r11);
	PUTREG(R12, r12);
	PUTREG(R13, r13);
	PUTREG(R14, r14);
	PUTREG(R15, r15);
#endif

	sc.cr2 = fi->cr2;
	sc.err = fi->error_code;
	sc.trapno = fi->trap_no;
	PUTREG(IP, ip);
	PUTREG(CS, cs);
	PUTREG(EFLAGS, flags);
#ifdef CONFIG_X86_32
	PUTREG(SP, sp_at_signal);
	PUTREG(SS, ss);
#endif
#undef PUTREG
	sc.oldmask = mask;
	sc.fpstate = to_fp;

	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
	if (err)
		return 1;

	pid = userspace_pid[current_thread_info()->cpu];

#ifdef CONFIG_X86_32
	if (have_fpx_regs) {
		struct user_fxsr_struct fpx;

		err = save_fpx_registers(pid, (unsigned long *) &fpx);
		if (err < 0){
			printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
			       "failed, errno = %d\n", err);
			return 1;
		}

		err = convert_fxsr_to_user(to_fp, &fpx);
		if (err)
			return 1;

		err |= __put_user(fpx.swd, &to_fp->status);
		err |= __put_user(X86_FXSR_MAGIC, &to_fp->magic);
		if (err)
			return 1;

		if (copy_to_user(&to_fp->_fxsr_env[0], &fpx,
				 sizeof(struct user_fxsr_struct)))
			return 1;
	} else
#endif
	{
		struct user_i387_struct fp;

		err = save_fp_registers(pid, (unsigned long *) &fp);
		if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
			return 1;
	}

	return 0;
}

#ifdef CONFIG_X86_32
static int copy_ucontext_to_user(struct ucontext __user *uc,
				 struct _fpstate __user *fp, sigset_t *set,
				 unsigned long sp)
{
	int err = 0;

	err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
	err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
	err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
	err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
	err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
	return err;
}

struct sigframe
{
	char __user *pretcode;
	int sig;
	struct sigcontext sc;
	struct _fpstate fpstate;
	unsigned long extramask[_NSIG_WORDS-1];
	char retcode[8];
};

struct rt_sigframe
{
	char __user *pretcode;
	int sig;
	struct siginfo __user *pinfo;
	void __user *puc;
	struct siginfo info;
	struct ucontext uc;
	struct _fpstate fpstate;
	char retcode[8];
};

int setup_signal_stack_sc(unsigned long stack_top, int sig,
			  struct k_sigaction *ka, struct pt_regs *regs,
			  sigset_t *mask)
{
	struct sigframe __user *frame;
	void __user *restorer;
	int err = 0;

	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
	stack_top = ((stack_top + 4) & -16UL) - 4;
	frame = (struct sigframe __user *) stack_top - 1;
	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		return 1;

	restorer = frame->retcode;
	if (ka->sa.sa_flags & SA_RESTORER)
		restorer = ka->sa.sa_restorer;

	err |= __put_user(restorer, &frame->pretcode);
	err |= __put_user(sig, &frame->sig);
	err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
	if (_NSIG_WORDS > 1)
		err |= __copy_to_user(&frame->extramask, &mask->sig[1],
				      sizeof(frame->extramask));

	/*
	 * This is popl %eax ; movl $,%eax ; int $0x80
	 *
	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
	 * reasons and because gdb uses it as a signature to notice
	 * signal handler stack frames.
	 */
	err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
	err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
	err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));

	if (err)
		return err;

	PT_REGS_SP(regs) = (unsigned long) frame;
	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
	PT_REGS_EAX(regs) = (unsigned long) sig;
	PT_REGS_EDX(regs) = (unsigned long) 0;
	PT_REGS_ECX(regs) = (unsigned long) 0;

	if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
		ptrace_notify(SIGTRAP);
	return 0;
}

int setup_signal_stack_si(unsigned long stack_top, int sig,
			  struct k_sigaction *ka, struct pt_regs *regs,
			  siginfo_t *info, sigset_t *mask)
{
	struct rt_sigframe __user *frame;
	void __user *restorer;
	int err = 0;

	stack_top &= -8UL;
	frame = (struct rt_sigframe __user *) stack_top - 1;
	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		return 1;

	restorer = frame->retcode;
	if (ka->sa.sa_flags & SA_RESTORER)
		restorer = ka->sa.sa_restorer;

	err |= __put_user(restorer, &frame->pretcode);
	err |= __put_user(sig, &frame->sig);
	err |= __put_user(&frame->info, &frame->pinfo);
	err |= __put_user(&frame->uc, &frame->puc);
	err |= copy_siginfo_to_user(&frame->info, info);
	err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
					PT_REGS_SP(regs));

	/*
	 * This is movl $,%eax ; int $0x80
	 *
	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
	 * reasons and because gdb uses it as a signature to notice
	 * signal handler stack frames.
	 */
	err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
	err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
	err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));

	if (err)
		return err;

	PT_REGS_SP(regs) = (unsigned long) frame;
	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
	PT_REGS_EAX(regs) = (unsigned long) sig;
	PT_REGS_EDX(regs) = (unsigned long) &frame->info;
	PT_REGS_ECX(regs) = (unsigned long) &frame->uc;

	if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
		ptrace_notify(SIGTRAP);
	return 0;
}

long sys_sigreturn(struct pt_regs *regs)
{
	unsigned long sp = PT_REGS_SP(&current->thread.regs);
	struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
	sigset_t set;
	struct sigcontext __user *sc = &frame->sc;
	unsigned long __user *oldmask = &sc->oldmask;
	unsigned long __user *extramask = frame->extramask;
	int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);

	if (copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) ||
	    copy_from_user(&set.sig[1], extramask, sig_size))
		goto segfault;

	sigdelsetmask(&set, ~_BLOCKABLE);
	set_current_blocked(&set);

	if (copy_sc_from_user(&current->thread.regs, sc))
		goto segfault;

	/* Avoid ERESTART handling */
	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
	return PT_REGS_SYSCALL_RET(&current->thread.regs);

 segfault:
	force_sig(SIGSEGV, current);
	return 0;
}

#else

struct rt_sigframe
{
	char __user *pretcode;
	struct ucontext uc;
	struct siginfo info;
	struct _fpstate fpstate;
};

int setup_signal_stack_si(unsigned long stack_top, int sig,
			  struct k_sigaction *ka, struct pt_regs * regs,
			  siginfo_t *info, sigset_t *set)
{
	struct rt_sigframe __user *frame;
	int err = 0;
	struct task_struct *me = current;

	frame = (struct rt_sigframe __user *)
		round_down(stack_top - sizeof(struct rt_sigframe), 16);
	/* Subtract 128 for a red zone and 8 for proper alignment */
	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto out;

	if (ka->sa.sa_flags & SA_SIGINFO) {
		err |= copy_siginfo_to_user(&frame->info, info);
		if (err)
			goto out;
	}

	/* Create the ucontext.  */
	err |= __put_user(0, &frame->uc.uc_flags);
	err |= __put_user(0, &frame->uc.uc_link);
	err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
	err |= __put_user(sas_ss_flags(PT_REGS_SP(regs)),
			  &frame->uc.uc_stack.ss_flags);
	err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
	err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
			       set->sig[0]);
	err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
	if (sizeof(*set) == 16) {
		__put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
		__put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
	}
	else
		err |= __copy_to_user(&frame->uc.uc_sigmask, set,
				      sizeof(*set));

	/*
	 * Set up to return from userspace.  If provided, use a stub
	 * already in userspace.
	 */
	/* x86-64 should always use SA_RESTORER. */
	if (ka->sa.sa_flags & SA_RESTORER)
		err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
	else
		/* could use a vstub here */
		return err;

	if (err)
		return err;

	/* Set up registers for signal handler */
	{
		struct exec_domain *ed = current_thread_info()->exec_domain;
		if (unlikely(ed && ed->signal_invmap && sig < 32))
			sig = ed->signal_invmap[sig];
	}

	PT_REGS_SP(regs) = (unsigned long) frame;
	PT_REGS_RDI(regs) = sig;
	/* In case the signal handler was declared without prototypes */
	PT_REGS_RAX(regs) = 0;

	/*
	 * This also works for non SA_SIGINFO handlers because they expect the
	 * next argument after the signal number on the stack.
	 */
	PT_REGS_RSI(regs) = (unsigned long) &frame->info;
	PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
	PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
 out:
	return err;
}
#endif

long sys_rt_sigreturn(struct pt_regs *regs)
{
	unsigned long sp = PT_REGS_SP(&current->thread.regs);
	struct rt_sigframe __user *frame =
		(struct rt_sigframe __user *)(sp - sizeof(long));
	struct ucontext __user *uc = &frame->uc;
	sigset_t set;

	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
		goto segfault;

	sigdelsetmask(&set, ~_BLOCKABLE);
	set_current_blocked(&set);

	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
		goto segfault;

	/* Avoid ERESTART handling */
	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
	return PT_REGS_SYSCALL_RET(&current->thread.regs);

 segfault:
	force_sig(SIGSEGV, current);
	return 0;
}

#ifdef CONFIG_X86_32
long ptregs_sigreturn(void)
{
	return sys_sigreturn(NULL);
}
long ptregs_rt_sigreturn(void)
{
	return sys_rt_sigreturn(NULL);
}
#endif
Commit	Line	Data
1da177e4	1	/*
f67aa2ff AV	2	* Copyright (C) 2003 PathScale, Inc.
f67aa2ff AV	3	* Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
1da177e4 LT	4	* Licensed under the GPL
	5	*/
	6
f67aa2ff AV	7
f67aa2ff AV	8	#include <linux/personality.h>
7796931f	9	#include <linux/ptrace.h>
f67aa2ff	10	#include <linux/kernel.h>
7796931f JD	11	#include <asm/unistd.h>
	12	#include <asm/uaccess.h>
	13	#include <asm/ucontext.h>
1da177e4	14	#include "frame_kern.h"
1da177e4 LT	15	#include "skas.h"
1da177e4 LT	16
f67aa2ff AV	17	#ifdef CONFIG_X86_32
f67aa2ff AV	18
a5f6096c JD	19	/*
	20	* FPU tag word conversions.
	21	*/
	22
	23	static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
	24	{
	25	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
	26
	27	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
	28	tmp = ~twd;
	29	tmp = (tmp \| (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
	30	/* and move the valid bits to the lower byte. */
	31	tmp = (tmp \| (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
	32	tmp = (tmp \| (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
	33	tmp = (tmp \| (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
	34	return tmp;
	35	}
	36
	37	static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
	38	{
	39	struct _fpxreg *st = NULL;
	40	unsigned long twd = (unsigned long) fxsave->twd;
	41	unsigned long tag;
	42	unsigned long ret = 0xffff0000;
	43	int i;
	44
497888cf	45	#define FPREG_ADDR(f, n) ((char )&(f)->st_space + (n) 16)
a5f6096c JD	46
	47	for (i = 0; i < 8; i++) {
	48	if (twd & 0x1) {
	49	st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
	50
	51	switch (st->exponent & 0x7fff) {
	52	case 0x7fff:
	53	tag = 2; /* Special */
	54	break;
	55	case 0x0000:
	56	if ( !st->significand[0] &&
	57	!st->significand[1] &&
	58	!st->significand[2] &&
	59	!st->significand[3] ) {
	60	tag = 1; /* Zero */
	61	} else {
	62	tag = 2; /* Special */
	63	}
	64	break;
	65	default:
	66	if (st->significand[3] & 0x8000) {
	67	tag = 0; /* Valid */
	68	} else {
	69	tag = 2; /* Special */
	70	}
	71	break;
	72	}
	73	} else {
	74	tag = 3; /* Empty */
	75	}
	76	ret \|= (tag << (2 * i));
	77	twd = twd >> 1;
	78	}
	79	return ret;
	80	}
	81
	82	static int convert_fxsr_to_user(struct _fpstate __user *buf,
	83	struct user_fxsr_struct *fxsave)
	84	{
	85	unsigned long env[7];
	86	struct _fpreg __user *to;
	87	struct _fpxreg *from;
	88	int i;
	89
	90	env[0] = (unsigned long)fxsave->cwd \| 0xffff0000ul;
	91	env[1] = (unsigned long)fxsave->swd \| 0xffff0000ul;
	92	env[2] = twd_fxsr_to_i387(fxsave);
	93	env[3] = fxsave->fip;
	94	env[4] = fxsave->fcs \| ((unsigned long)fxsave->fop << 16);
	95	env[5] = fxsave->foo;
	96	env[6] = fxsave->fos;
	97
	98	if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
	99	return 1;
	100
	101	to = &buf->_st[0];
	102	from = (struct _fpxreg *) &fxsave->st_space[0];
	103	for (i = 0; i < 8; i++, to++, from++) {
	104	unsigned long __user t = (unsigned long __user )to;
	105	unsigned long f = (unsigned long )from;
	106
	107	if (__put_user(*f, t) \|\|
	108	__put_user(*(f + 1), t + 1) \|\|
	109	__put_user(from->exponent, &to->exponent))
110	return 1;
111	}
112	return 0;
113	}
114
115	static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
116	struct _fpstate __user *buf)
117	{
118	unsigned long env[7];
119	struct _fpxreg *to;
120	struct _fpreg __user *from;
121	int i;
122
123	if (copy_from_user( env, buf, 7 * sizeof(long)))
124	return 1;
125
126	fxsave->cwd = (unsigned short)(env[0] & 0xffff);
127	fxsave->swd = (unsigned short)(env[1] & 0xffff);
128	fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
129	fxsave->fip = env[3];
130	fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
131	fxsave->fcs = (env[4] & 0xffff);
132	fxsave->foo = env[5];
133	fxsave->fos = env[6];
134
135	to = (struct _fpxreg *) &fxsave->st_space[0];
136	from = &buf->_st[0];
137	for (i = 0; i < 8; i++, to++, from++) {
138	unsigned long t = (unsigned long )to;
139	unsigned long __user f = (unsigned long __user )from;
140
141	if (__get_user(*t, f) \|\|
142	__get_user(*(t + 1), f + 1) \|\|
143	__get_user(to->exponent, &from->exponent))
144	return 1;
145	}
146	return 0;
147	}
148
149	extern int have_fpx_regs;
150
f67aa2ff AV	151	#endif
f67aa2ff AV	152
77bf4400 JD	153	static int copy_sc_from_user(struct pt_regs *regs,
77bf4400 JD	154	struct sigcontext __user *from)
1da177e4	155	{
a5f6096c	156	struct sigcontext sc;
a5a678c8	157	int err, pid;
1da177e4	158
3b7d15bd AV	159	/* Always make any pending restarted system calls return -EINTR */
	160	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	161
1da177e4	162	err = copy_from_user(&sc, from, sizeof(sc));
ba180fd4	163	if (err)
5d86456d	164	return err;
1da177e4	165
a955bd61 AV	166	#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
a955bd61 AV	167
f67aa2ff	168	#ifdef CONFIG_X86_32
a955bd61 AV	169	GETREG(GS, gs);
	170	GETREG(FS, fs);
	171	GETREG(ES, es);
	172	GETREG(DS, ds);
f67aa2ff	173	#endif
3579a389 AV	174	GETREG(DI, di);
	175	GETREG(SI, si);
	176	GETREG(BP, bp);
a955bd61	177	GETREG(SP, sp);
3579a389 AV	178	GETREG(BX, bx);
	179	GETREG(DX, dx);
	180	GETREG(CX, cx);
	181	GETREG(AX, ax);
a955bd61	182	GETREG(IP, ip);
f67aa2ff AV	183
	184	#ifdef CONFIG_X86_64
	185	GETREG(R8, r8);
	186	GETREG(R9, r9);
	187	GETREG(R10, r10);
	188	GETREG(R11, r11);
	189	GETREG(R12, r12);
	190	GETREG(R13, r13);
	191	GETREG(R14, r14);
	192	GETREG(R15, r15);
	193	#endif
	194
a955bd61 AV	195	GETREG(CS, cs);
a955bd61 AV	196	GETREG(EFLAGS, flags);
f67aa2ff	197	#ifdef CONFIG_X86_32
a955bd61	198	GETREG(SS, ss);
f67aa2ff	199	#endif
a955bd61 AV	200
a955bd61 AV	201	#undef GETREG
f67aa2ff AV	202
	203	pid = userspace_pid[current_thread_info()->cpu];
	204	#ifdef CONFIG_X86_32
a5f6096c JD	205	if (have_fpx_regs) {
a5f6096c JD	206	struct user_fxsr_struct fpx;
1da177e4	207
966c8079 WC	208	err = copy_from_user(&fpx,
966c8079 WC	209	&((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
a5f6096c JD	210	sizeof(struct user_fxsr_struct));
	211	if (err)
	212	return 1;
	213
	214	err = convert_fxsr_from_user(&fpx, sc.fpstate);
	215	if (err)
	216	return 1;
	217
a5a678c8	218	err = restore_fpx_registers(pid, (unsigned long *) &fpx);
a5f6096c JD	219	if (err < 0) {
	220	printk(KERN_ERR "copy_sc_from_user - "
	221	"restore_fpx_registers failed, errno = %d\n",
	222	-err);
	223	return 1;
	224	}
f67aa2ff AV	225	} else
	226	#endif
	227	{
a5f6096c JD	228	struct user_i387_struct fp;
	229
	230	err = copy_from_user(&fp, sc.fpstate,
	231	sizeof(struct user_i387_struct));
	232	if (err)
	233	return 1;
	234
a5a678c8	235	err = restore_fp_registers(pid, (unsigned long *) &fp);
a5f6096c JD	236	if (err < 0) {
	237	printk(KERN_ERR "copy_sc_from_user - "
	238	"restore_fp_registers failed, errno = %d\n",
	239	-err);
	240	return 1;
	241	}
1da177e4	242	}
5d86456d	243	return 0;
1da177e4 LT	244	}
1da177e4 LT	245
77bf4400	246	static int copy_sc_to_user(struct sigcontext __user *to,
f67aa2ff AV	247	struct _fpstate __user to_fp, struct pt_regs regs,
f67aa2ff AV	248	unsigned long mask)
1da177e4	249	{
ba180fd4	250	struct sigcontext sc;
c578455a	251	struct faultinfo * fi = &current->thread.arch.faultinfo;
a5a678c8	252	int err, pid;
a955bd61	253	memset(&sc, 0, sizeof(struct sigcontext));
1da177e4	254
f67aa2ff AV	255	#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
	256
	257	#ifdef CONFIG_X86_32
	258	PUTREG(GS, gs);
	259	PUTREG(FS, fs);
	260	PUTREG(ES, es);
	261	PUTREG(DS, ds);
	262	#endif
	263	PUTREG(DI, di);
	264	PUTREG(SI, si);
	265	PUTREG(BP, bp);
	266	PUTREG(SP, sp);
	267	PUTREG(BX, bx);
	268	PUTREG(DX, dx);
	269	PUTREG(CX, cx);
	270	PUTREG(AX, ax);
	271	#ifdef CONFIG_X86_64
	272	PUTREG(R8, r8);
	273	PUTREG(R9, r9);
	274	PUTREG(R10, r10);
	275	PUTREG(R11, r11);
	276	PUTREG(R12, r12);
	277	PUTREG(R13, r13);
	278	PUTREG(R14, r14);
	279	PUTREG(R15, r15);
	280	#endif
	281
ba180fd4 JD	282	sc.cr2 = fi->cr2;
	283	sc.err = fi->error_code;
	284	sc.trapno = fi->trap_no;
f67aa2ff AV	285	PUTREG(IP, ip);
	286	PUTREG(CS, cs);
	287	PUTREG(EFLAGS, flags);
	288	#ifdef CONFIG_X86_32
	289	PUTREG(SP, sp_at_signal);
	290	PUTREG(SS, ss);
	291	#endif
	292	#undef PUTREG
	293	sc.oldmask = mask;
1da177e4 LT	294	sc.fpstate = to_fp;
1da177e4 LT	295
f67aa2ff AV	296	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
	297	if (err)
	298	return 1;
	299
a5a678c8	300	pid = userspace_pid[current_thread_info()->cpu];
f67aa2ff AV	301
f67aa2ff AV	302	#ifdef CONFIG_X86_32
a5f6096c JD	303	if (have_fpx_regs) {
	304	struct user_fxsr_struct fpx;
	305
a5a678c8	306	err = save_fpx_registers(pid, (unsigned long *) &fpx);
a5f6096c JD	307	if (err < 0){
	308	printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
	309	"failed, errno = %d\n", err);
	310	return 1;
	311	}
	312
	313	err = convert_fxsr_to_user(to_fp, &fpx);
	314	if (err)
	315	return 1;
	316
	317	err \|= __put_user(fpx.swd, &to_fp->status);
	318	err \|= __put_user(X86_FXSR_MAGIC, &to_fp->magic);
	319	if (err)
	320	return 1;
	321
	322	if (copy_to_user(&to_fp->_fxsr_env[0], &fpx,
	323	sizeof(struct user_fxsr_struct)))
	324	return 1;
f67aa2ff AV	325	} else
	326	#endif
	327	{
a5f6096c JD	328	struct user_i387_struct fp;
a5f6096c JD	329
a5a678c8	330	err = save_fp_registers(pid, (unsigned long *) &fp);
a5f6096c JD	331	if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
	332	return 1;
	333	}
1da177e4	334
f67aa2ff	335	return 0;
1da177e4	336	}
1da177e4	337
f67aa2ff	338	#ifdef CONFIG_X86_32
ba180fd4 JD	339	static int copy_ucontext_to_user(struct ucontext __user *uc,
	340	struct _fpstate __user fp, sigset_t set,
	341	unsigned long sp)
1da177e4 LT	342	{
	343	int err = 0;
	344
	345	err \|= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
	346	err \|= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
	347	err \|= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
f67aa2ff	348	err \|= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
1da177e4	349	err \|= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
5d86456d	350	return err;
1da177e4 LT	351	}
	352
	353	struct sigframe
	354	{
4d338e1a	355	char __user *pretcode;
1da177e4 LT	356	int sig;
	357	struct sigcontext sc;
	358	struct _fpstate fpstate;
	359	unsigned long extramask[_NSIG_WORDS-1];
	360	char retcode[8];
	361	};
	362
	363	struct rt_sigframe
	364	{
4d338e1a	365	char __user *pretcode;
1da177e4	366	int sig;
4d338e1a AV	367	struct siginfo __user *pinfo;
4d338e1a AV	368	void __user *puc;
1da177e4 LT	369	struct siginfo info;
	370	struct ucontext uc;
	371	struct _fpstate fpstate;
	372	char retcode[8];
	373	};
	374
	375	int setup_signal_stack_sc(unsigned long stack_top, int sig,
	376	struct k_sigaction ka, struct pt_regs regs,
	377	sigset_t *mask)
	378	{
	379	struct sigframe __user *frame;
4d338e1a	380	void __user *restorer;
1da177e4 LT	381	int err = 0;
1da177e4 LT	382
3896625d JD	383	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
3896625d JD	384	stack_top = ((stack_top + 4) & -16UL) - 4;
4d338e1a	385	frame = (struct sigframe __user *) stack_top - 1;
1da177e4 LT	386	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	387	return 1;
	388
4d338e1a	389	restorer = frame->retcode;
ba180fd4	390	if (ka->sa.sa_flags & SA_RESTORER)
1da177e4 LT	391	restorer = ka->sa.sa_restorer;
	392
	393	err \|= __put_user(restorer, &frame->pretcode);
	394	err \|= __put_user(sig, &frame->sig);
f67aa2ff	395	err \|= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
1da177e4 LT	396	if (_NSIG_WORDS > 1)
	397	err \|= __copy_to_user(&frame->extramask, &mask->sig[1],
	398	sizeof(frame->extramask));
	399
	400	/*
	401	* This is popl %eax ; movl $,%eax ; int $0x80
	402	*
	403	* WE DO NOT USE IT ANY MORE! It's only left here for historical
	404	* reasons and because gdb uses it as a signature to notice
	405	* signal handler stack frames.
	406	*/
	407	err \|= __put_user(0xb858, (short __user *)(frame->retcode+0));
	408	err \|= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
	409	err \|= __put_user(0x80cd, (short __user *)(frame->retcode+6));
	410
ba180fd4	411	if (err)
fbe98686	412	return err;
1da177e4 LT	413
	414	PT_REGS_SP(regs) = (unsigned long) frame;
	415	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
	416	PT_REGS_EAX(regs) = (unsigned long) sig;
	417	PT_REGS_EDX(regs) = (unsigned long) 0;
	418	PT_REGS_ECX(regs) = (unsigned long) 0;
	419
	420	if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
	421	ptrace_notify(SIGTRAP);
98c18238	422	return 0;
1da177e4 LT	423	}
	424
	425	int setup_signal_stack_si(unsigned long stack_top, int sig,
	426	struct k_sigaction ka, struct pt_regs regs,
	427	siginfo_t info, sigset_t mask)
	428	{
	429	struct rt_sigframe __user *frame;
4d338e1a	430	void __user *restorer;
1da177e4 LT	431	int err = 0;
	432
	433	stack_top &= -8UL;
4d338e1a	434	frame = (struct rt_sigframe __user *) stack_top - 1;
1da177e4 LT	435	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	436	return 1;
	437
4d338e1a	438	restorer = frame->retcode;
ba180fd4	439	if (ka->sa.sa_flags & SA_RESTORER)
1da177e4 LT	440	restorer = ka->sa.sa_restorer;
	441
	442	err \|= __put_user(restorer, &frame->pretcode);
	443	err \|= __put_user(sig, &frame->sig);
	444	err \|= __put_user(&frame->info, &frame->pinfo);
	445	err \|= __put_user(&frame->uc, &frame->puc);
	446	err \|= copy_siginfo_to_user(&frame->info, info);
	447	err \|= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
fbe98686	448	PT_REGS_SP(regs));
1da177e4 LT	449
	450	/*
	451	* This is movl $,%eax ; int $0x80
	452	*
	453	* WE DO NOT USE IT ANY MORE! It's only left here for historical
	454	* reasons and because gdb uses it as a signature to notice
	455	* signal handler stack frames.
	456	*/
	457	err \|= __put_user(0xb8, (char __user *)(frame->retcode+0));
	458	err \|= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
	459	err \|= __put_user(0x80cd, (short __user *)(frame->retcode+5));
	460
ba180fd4	461	if (err)
fbe98686	462	return err;
1da177e4	463
fbe98686	464	PT_REGS_SP(regs) = (unsigned long) frame;
1da177e4 LT	465	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
	466	PT_REGS_EAX(regs) = (unsigned long) sig;
	467	PT_REGS_EDX(regs) = (unsigned long) &frame->info;
	468	PT_REGS_ECX(regs) = (unsigned long) &frame->uc;
	469
	470	if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
	471	ptrace_notify(SIGTRAP);
98c18238	472	return 0;
1da177e4 LT	473	}
1da177e4 LT	474
f67aa2ff	475	long sys_sigreturn(struct pt_regs *regs)
1da177e4 LT	476	{
1da177e4 LT	477	unsigned long sp = PT_REGS_SP(&current->thread.regs);
4d338e1a	478	struct sigframe __user frame = (struct sigframe __user )(sp - 8);
1da177e4 LT	479	sigset_t set;
	480	struct sigcontext __user *sc = &frame->sc;
	481	unsigned long __user *oldmask = &sc->oldmask;
	482	unsigned long __user *extramask = frame->extramask;
	483	int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
	484
ba180fd4 JD	485	if (copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) \|\|
ba180fd4 JD	486	copy_from_user(&set.sig[1], extramask, sig_size))
1da177e4 LT	487	goto segfault;
	488
	489	sigdelsetmask(&set, ~_BLOCKABLE);
78722a44	490	set_current_blocked(&set);
1da177e4	491
ba180fd4	492	if (copy_sc_from_user(&current->thread.regs, sc))
1da177e4 LT	493	goto segfault;
	494
	495	/* Avoid ERESTART handling */
	496	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
5d86456d	497	return PT_REGS_SYSCALL_RET(&current->thread.regs);
1da177e4 LT	498
	499	segfault:
	500	force_sig(SIGSEGV, current);
	501	return 0;
	502	}
	503
f67aa2ff AV	504	#else
	505
	506	struct rt_sigframe
	507	{
	508	char __user *pretcode;
	509	struct ucontext uc;
	510	struct siginfo info;
	511	struct _fpstate fpstate;
	512	};
	513
	514	int setup_signal_stack_si(unsigned long stack_top, int sig,
	515	struct k_sigaction ka, struct pt_regs regs,
	516	siginfo_t info, sigset_t set)
	517	{
	518	struct rt_sigframe __user *frame;
	519	int err = 0;
	520	struct task_struct *me = current;
	521
	522	frame = (struct rt_sigframe __user *)
	523	round_down(stack_top - sizeof(struct rt_sigframe), 16);
	524	/* Subtract 128 for a red zone and 8 for proper alignment */
	525	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
	526
	527	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	528	goto out;
	529
	530	if (ka->sa.sa_flags & SA_SIGINFO) {
	531	err \|= copy_siginfo_to_user(&frame->info, info);
	532	if (err)
	533	goto out;
	534	}
	535
	536	/* Create the ucontext. */
	537	err \|= __put_user(0, &frame->uc.uc_flags);
	538	err \|= __put_user(0, &frame->uc.uc_link);
	539	err \|= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
	540	err \|= __put_user(sas_ss_flags(PT_REGS_SP(regs)),
	541	&frame->uc.uc_stack.ss_flags);
	542	err \|= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
	543	err \|= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
	544	set->sig[0]);
	545	err \|= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
	546	if (sizeof(*set) == 16) {
	547	__put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
	548	__put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
	549	}
	550	else
	551	err \|= __copy_to_user(&frame->uc.uc_sigmask, set,
	552	sizeof(*set));
	553
	554	/*
	555	* Set up to return from userspace. If provided, use a stub
	556	* already in userspace.
	557	*/
	558	/* x86-64 should always use SA_RESTORER. */
	559	if (ka->sa.sa_flags & SA_RESTORER)
	560	err \|= __put_user(ka->sa.sa_restorer, &frame->pretcode);
	561	else
	562	/* could use a vstub here */
	563	return err;
	564
	565	if (err)
	566	return err;
	567
568	/* Set up registers for signal handler */
569	{
570	struct exec_domain *ed = current_thread_info()->exec_domain;
571	if (unlikely(ed && ed->signal_invmap && sig < 32))
572	sig = ed->signal_invmap[sig];
573	}
574
575	PT_REGS_SP(regs) = (unsigned long) frame;
576	PT_REGS_RDI(regs) = sig;
577	/* In case the signal handler was declared without prototypes */
578	PT_REGS_RAX(regs) = 0;
579
580	/*
581	* This also works for non SA_SIGINFO handlers because they expect the
582	* next argument after the signal number on the stack.
583	*/
584	PT_REGS_RSI(regs) = (unsigned long) &frame->info;
585	PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
586	PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
587	out:
588	return err;
589	}
590	#endif
591
592	long sys_rt_sigreturn(struct pt_regs *regs)
1da177e4	593	{
4d338e1a	594	unsigned long sp = PT_REGS_SP(&current->thread.regs);
ba180fd4	595	struct rt_sigframe __user *frame =
f67aa2ff	596	(struct rt_sigframe __user *)(sp - sizeof(long));
1da177e4	597	struct ucontext __user *uc = &frame->uc;
f67aa2ff	598	sigset_t set;
1da177e4	599
f67aa2ff	600	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
1da177e4 LT	601	goto segfault;
	602
	603	sigdelsetmask(&set, ~_BLOCKABLE);
78722a44	604	set_current_blocked(&set);
1da177e4	605
ba180fd4	606	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
1da177e4 LT	607	goto segfault;
	608
	609	/* Avoid ERESTART handling */
	610	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
5d86456d	611	return PT_REGS_SYSCALL_RET(&current->thread.regs);
1da177e4 LT	612
	613	segfault:
	614	force_sig(SIGSEGV, current);
	615	return 0;
	616	}
f67aa2ff AV	617
	618	#ifdef CONFIG_X86_32
	619	long ptregs_sigreturn(void)
	620	{
	621	return sys_sigreturn(NULL);
	622	}
	623	long ptregs_rt_sigreturn(void)
	624	{
	625	return sys_rt_sigreturn(NULL);
	626	}
	627	#endif