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v6.8
  1/*
  2 * Copyright (C) 2003 PathScale, Inc.
  3 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  4 * Licensed under the GPL
  5 */
  6
  7
  8#include <linux/personality.h>
  9#include <linux/ptrace.h>
 10#include <linux/kernel.h>
 11#include <asm/unistd.h>
 12#include <linux/uaccess.h>
 13#include <asm/ucontext.h>
 14#include <frame_kern.h>
 15#include <registers.h>
 16#include <skas.h>
 17
 18#ifdef CONFIG_X86_32
 19
 20/*
 21 * FPU tag word conversions.
 22 */
 23
 24static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
 25{
 26	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
 27
 28	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
 29	tmp = ~twd;
 30	tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
 31	/* and move the valid bits to the lower byte. */
 32	tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
 33	tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
 34	tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
 35	return tmp;
 36}
 37
 38static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
 39{
 40	struct _fpxreg *st = NULL;
 41	unsigned long twd = (unsigned long) fxsave->twd;
 42	unsigned long tag;
 43	unsigned long ret = 0xffff0000;
 44	int i;
 45
 46#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16)
 47
 48	for (i = 0; i < 8; i++) {
 49		if (twd & 0x1) {
 50			st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
 51
 52			switch (st->exponent & 0x7fff) {
 53			case 0x7fff:
 54				tag = 2;		/* Special */
 55				break;
 56			case 0x0000:
 57				if ( !st->significand[0] &&
 58				     !st->significand[1] &&
 59				     !st->significand[2] &&
 60				     !st->significand[3] ) {
 61					tag = 1;	/* Zero */
 62				} else {
 63					tag = 2;	/* Special */
 64				}
 65				break;
 66			default:
 67				if (st->significand[3] & 0x8000) {
 68					tag = 0;	/* Valid */
 69				} else {
 70					tag = 2;	/* Special */
 71				}
 72				break;
 73			}
 74		} else {
 75			tag = 3;			/* Empty */
 76		}
 77		ret |= (tag << (2 * i));
 78		twd = twd >> 1;
 79	}
 80	return ret;
 81}
 82
 83static int convert_fxsr_to_user(struct _fpstate __user *buf,
 84				struct user_fxsr_struct *fxsave)
 85{
 86	unsigned long env[7];
 87	struct _fpreg __user *to;
 88	struct _fpxreg *from;
 89	int i;
 90
 91	env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
 92	env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
 93	env[2] = twd_fxsr_to_i387(fxsave);
 94	env[3] = fxsave->fip;
 95	env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
 96	env[5] = fxsave->foo;
 97	env[6] = fxsave->fos;
 98
 99	if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
100		return 1;
101
102	to = &buf->_st[0];
103	from = (struct _fpxreg *) &fxsave->st_space[0];
104	for (i = 0; i < 8; i++, to++, from++) {
105		unsigned long __user *t = (unsigned long __user *)to;
106		unsigned long *f = (unsigned long *)from;
107
108		if (__put_user(*f, t) ||
109				__put_user(*(f + 1), t + 1) ||
110				__put_user(from->exponent, &to->exponent))
111			return 1;
112	}
113	return 0;
114}
115
116static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
117				  struct _fpstate __user *buf)
118{
119	unsigned long env[7];
120	struct _fpxreg *to;
121	struct _fpreg __user *from;
122	int i;
123
124	if (copy_from_user( env, buf, 7 * sizeof(long)))
125		return 1;
126
127	fxsave->cwd = (unsigned short)(env[0] & 0xffff);
128	fxsave->swd = (unsigned short)(env[1] & 0xffff);
129	fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
130	fxsave->fip = env[3];
131	fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
132	fxsave->fcs = (env[4] & 0xffff);
133	fxsave->foo = env[5];
134	fxsave->fos = env[6];
135
136	to = (struct _fpxreg *) &fxsave->st_space[0];
137	from = &buf->_st[0];
138	for (i = 0; i < 8; i++, to++, from++) {
139		unsigned long *t = (unsigned long *)to;
140		unsigned long __user *f = (unsigned long __user *)from;
141
142		if (__get_user(*t, f) ||
143		    __get_user(*(t + 1), f + 1) ||
144		    __get_user(to->exponent, &from->exponent))
145			return 1;
146	}
147	return 0;
148}
149
150extern int have_fpx_regs;
151
152#endif
153
154static int copy_sc_from_user(struct pt_regs *regs,
155			     struct sigcontext __user *from)
156{
157	struct sigcontext sc;
158	int err, pid;
159
160	/* Always make any pending restarted system calls return -EINTR */
161	current->restart_block.fn = do_no_restart_syscall;
162
163	err = copy_from_user(&sc, from, sizeof(sc));
164	if (err)
165		return err;
166
167#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
168
169#ifdef CONFIG_X86_32
170	GETREG(GS, gs);
171	GETREG(FS, fs);
172	GETREG(ES, es);
173	GETREG(DS, ds);
174#endif
175	GETREG(DI, di);
176	GETREG(SI, si);
177	GETREG(BP, bp);
178	GETREG(SP, sp);
179	GETREG(BX, bx);
180	GETREG(DX, dx);
181	GETREG(CX, cx);
182	GETREG(AX, ax);
183	GETREG(IP, ip);
184
185#ifdef CONFIG_X86_64
186	GETREG(R8, r8);
187	GETREG(R9, r9);
188	GETREG(R10, r10);
189	GETREG(R11, r11);
190	GETREG(R12, r12);
191	GETREG(R13, r13);
192	GETREG(R14, r14);
193	GETREG(R15, r15);
194#endif
195
196	GETREG(CS, cs);
197	GETREG(EFLAGS, flags);
198#ifdef CONFIG_X86_32
199	GETREG(SS, ss);
200#endif
201
202#undef GETREG
203
204	pid = userspace_pid[current_thread_info()->cpu];
205#ifdef CONFIG_X86_32
206	if (have_fpx_regs) {
207		struct user_fxsr_struct fpx;
208
209		err = copy_from_user(&fpx,
210			&((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
211				     sizeof(struct user_fxsr_struct));
212		if (err)
213			return 1;
214
215		err = convert_fxsr_from_user(&fpx, (void *)sc.fpstate);
216		if (err)
217			return 1;
218
219		err = restore_fpx_registers(pid, (unsigned long *) &fpx);
220		if (err < 0) {
221			printk(KERN_ERR "copy_sc_from_user - "
222			       "restore_fpx_registers failed, errno = %d\n",
223			       -err);
224			return 1;
225		}
226	} else
227#endif
228	{
229		err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
230				     sizeof(struct _xstate));
 
 
231		if (err)
232			return 1;
 
 
 
 
 
 
 
 
233	}
234	return 0;
235}
236
237static int copy_sc_to_user(struct sigcontext __user *to,
238			   struct _xstate __user *to_fp, struct pt_regs *regs,
239			   unsigned long mask)
240{
241	struct sigcontext sc;
242	struct faultinfo * fi = &current->thread.arch.faultinfo;
243	int err, pid;
244	memset(&sc, 0, sizeof(struct sigcontext));
245
246#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
247
248#ifdef CONFIG_X86_32
249	PUTREG(GS, gs);
250	PUTREG(FS, fs);
251	PUTREG(ES, es);
252	PUTREG(DS, ds);
253#endif
254	PUTREG(DI, di);
255	PUTREG(SI, si);
256	PUTREG(BP, bp);
257	PUTREG(SP, sp);
258	PUTREG(BX, bx);
259	PUTREG(DX, dx);
260	PUTREG(CX, cx);
261	PUTREG(AX, ax);
262#ifdef CONFIG_X86_64
263	PUTREG(R8, r8);
264	PUTREG(R9, r9);
265	PUTREG(R10, r10);
266	PUTREG(R11, r11);
267	PUTREG(R12, r12);
268	PUTREG(R13, r13);
269	PUTREG(R14, r14);
270	PUTREG(R15, r15);
271#endif
272
273	sc.cr2 = fi->cr2;
274	sc.err = fi->error_code;
275	sc.trapno = fi->trap_no;
276	PUTREG(IP, ip);
277	PUTREG(CS, cs);
278	PUTREG(EFLAGS, flags);
279#ifdef CONFIG_X86_32
280	PUTREG(SP, sp_at_signal);
281	PUTREG(SS, ss);
282#endif
283#undef PUTREG
284	sc.oldmask = mask;
285	sc.fpstate = (unsigned long)to_fp;
286
287	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
288	if (err)
289		return 1;
290
291	pid = userspace_pid[current_thread_info()->cpu];
292
293#ifdef CONFIG_X86_32
294	if (have_fpx_regs) {
295		struct user_fxsr_struct fpx;
296
297		err = save_fpx_registers(pid, (unsigned long *) &fpx);
298		if (err < 0){
299			printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
300			       "failed, errno = %d\n", err);
301			return 1;
302		}
303
304		err = convert_fxsr_to_user(&to_fp->fpstate, &fpx);
305		if (err)
306			return 1;
307
308		err |= __put_user(fpx.swd, &to_fp->fpstate.status);
309		err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
310		if (err)
311			return 1;
312
313		if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx,
314				 sizeof(struct user_fxsr_struct)))
315			return 1;
316	} else
317#endif
318	{
319		if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
 
 
 
320			return 1;
321	}
322
323	return 0;
324}
325
326#ifdef CONFIG_X86_32
327static int copy_ucontext_to_user(struct ucontext __user *uc,
328				 struct _xstate __user *fp, sigset_t *set,
329				 unsigned long sp)
330{
331	int err = 0;
332
333	err |= __save_altstack(&uc->uc_stack, sp);
 
 
334	err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
335	err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
336	return err;
337}
338
339struct sigframe
340{
341	char __user *pretcode;
342	int sig;
343	struct sigcontext sc;
344	struct _xstate fpstate;
345	unsigned long extramask[_NSIG_WORDS-1];
346	char retcode[8];
347};
348
349struct rt_sigframe
350{
351	char __user *pretcode;
352	int sig;
353	struct siginfo __user *pinfo;
354	void __user *puc;
355	struct siginfo info;
356	struct ucontext uc;
357	struct _xstate fpstate;
358	char retcode[8];
359};
360
361int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
362			  struct pt_regs *regs, sigset_t *mask)
 
363{
364	struct sigframe __user *frame;
365	void __user *restorer;
366	int err = 0, sig = ksig->sig;
367
368	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
369	stack_top = ((stack_top + 4) & -16UL) - 4;
370	frame = (struct sigframe __user *) stack_top - 1;
371	if (!access_ok(frame, sizeof(*frame)))
372		return 1;
373
374	restorer = frame->retcode;
375	if (ksig->ka.sa.sa_flags & SA_RESTORER)
376		restorer = ksig->ka.sa.sa_restorer;
377
378	err |= __put_user(restorer, &frame->pretcode);
379	err |= __put_user(sig, &frame->sig);
380	err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
381	if (_NSIG_WORDS > 1)
382		err |= __copy_to_user(&frame->extramask, &mask->sig[1],
383				      sizeof(frame->extramask));
384
385	/*
386	 * This is popl %eax ; movl $,%eax ; int $0x80
387	 *
388	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
389	 * reasons and because gdb uses it as a signature to notice
390	 * signal handler stack frames.
391	 */
392	err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
393	err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
394	err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
395
396	if (err)
397		return err;
398
399	PT_REGS_SP(regs) = (unsigned long) frame;
400	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
401	PT_REGS_AX(regs) = (unsigned long) sig;
402	PT_REGS_DX(regs) = (unsigned long) 0;
403	PT_REGS_CX(regs) = (unsigned long) 0;
 
 
 
404	return 0;
405}
406
407int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
408			  struct pt_regs *regs, sigset_t *mask)
 
409{
410	struct rt_sigframe __user *frame;
411	void __user *restorer;
412	int err = 0, sig = ksig->sig;
413
414	stack_top &= -8UL;
415	frame = (struct rt_sigframe __user *) stack_top - 1;
416	if (!access_ok(frame, sizeof(*frame)))
417		return 1;
418
419	restorer = frame->retcode;
420	if (ksig->ka.sa.sa_flags & SA_RESTORER)
421		restorer = ksig->ka.sa.sa_restorer;
422
423	err |= __put_user(restorer, &frame->pretcode);
424	err |= __put_user(sig, &frame->sig);
425	err |= __put_user(&frame->info, &frame->pinfo);
426	err |= __put_user(&frame->uc, &frame->puc);
427	err |= copy_siginfo_to_user(&frame->info, &ksig->info);
428	err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
429					PT_REGS_SP(regs));
430
431	/*
432	 * This is movl $,%eax ; int $0x80
433	 *
434	 * WE DO NOT USE IT ANY MORE! It's only left here for historical
435	 * reasons and because gdb uses it as a signature to notice
436	 * signal handler stack frames.
437	 */
438	err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
439	err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
440	err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
441
442	if (err)
443		return err;
444
445	PT_REGS_SP(regs) = (unsigned long) frame;
446	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
447	PT_REGS_AX(regs) = (unsigned long) sig;
448	PT_REGS_DX(regs) = (unsigned long) &frame->info;
449	PT_REGS_CX(regs) = (unsigned long) &frame->uc;
 
 
 
450	return 0;
451}
452
453long sys_sigreturn(void)
454{
455	unsigned long sp = PT_REGS_SP(&current->thread.regs);
456	struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
457	sigset_t set;
458	struct sigcontext __user *sc = &frame->sc;
 
 
459	int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
460
461	if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) ||
462	    copy_from_user(&set.sig[1], frame->extramask, sig_size))
463		goto segfault;
464
465	set_current_blocked(&set);
466
467	if (copy_sc_from_user(&current->thread.regs, sc))
468		goto segfault;
469
470	/* Avoid ERESTART handling */
471	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
472	return PT_REGS_SYSCALL_RET(&current->thread.regs);
473
474 segfault:
475	force_sig(SIGSEGV);
476	return 0;
477}
478
479#else
480
481struct rt_sigframe
482{
483	char __user *pretcode;
484	struct ucontext uc;
485	struct siginfo info;
486	struct _xstate fpstate;
487};
488
489int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
490			  struct pt_regs *regs, sigset_t *set)
 
491{
492	struct rt_sigframe __user *frame;
493	int err = 0, sig = ksig->sig;
494	unsigned long fp_to;
495
496	frame = (struct rt_sigframe __user *)
497		round_down(stack_top - sizeof(struct rt_sigframe), 16);
498	/* Subtract 128 for a red zone and 8 for proper alignment */
499	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
500
501	if (!access_ok(frame, sizeof(*frame)))
502		goto out;
503
504	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
505		err |= copy_siginfo_to_user(&frame->info, &ksig->info);
506		if (err)
507			goto out;
508	}
509
510	/* Create the ucontext.  */
511	err |= __put_user(0, &frame->uc.uc_flags);
512	err |= __put_user(0, &frame->uc.uc_link);
513	err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
 
 
 
514	err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
515			       set->sig[0]);
516
517	fp_to = (unsigned long)&frame->fpstate;
518
519	err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
520	if (sizeof(*set) == 16) {
521		err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
522		err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
523	}
524	else
525		err |= __copy_to_user(&frame->uc.uc_sigmask, set,
526				      sizeof(*set));
527
528	/*
529	 * Set up to return from userspace.  If provided, use a stub
530	 * already in userspace.
531	 */
532	/* x86-64 should always use SA_RESTORER. */
533	if (ksig->ka.sa.sa_flags & SA_RESTORER)
534		err |= __put_user((void *)ksig->ka.sa.sa_restorer,
535				  &frame->pretcode);
536	else
537		/* could use a vstub here */
538		return err;
539
540	if (err)
541		return err;
542
 
 
 
 
 
 
 
543	PT_REGS_SP(regs) = (unsigned long) frame;
544	PT_REGS_DI(regs) = sig;
545	/* In case the signal handler was declared without prototypes */
546	PT_REGS_AX(regs) = 0;
547
548	/*
549	 * This also works for non SA_SIGINFO handlers because they expect the
550	 * next argument after the signal number on the stack.
551	 */
552	PT_REGS_SI(regs) = (unsigned long) &frame->info;
553	PT_REGS_DX(regs) = (unsigned long) &frame->uc;
554	PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
555 out:
556	return err;
557}
558#endif
559
560long sys_rt_sigreturn(void)
561{
562	unsigned long sp = PT_REGS_SP(&current->thread.regs);
563	struct rt_sigframe __user *frame =
564		(struct rt_sigframe __user *)(sp - sizeof(long));
565	struct ucontext __user *uc = &frame->uc;
566	sigset_t set;
567
568	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
569		goto segfault;
570
571	set_current_blocked(&set);
572
573	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
574		goto segfault;
575
576	/* Avoid ERESTART handling */
577	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
578	return PT_REGS_SYSCALL_RET(&current->thread.regs);
579
580 segfault:
581	force_sig(SIGSEGV);
582	return 0;
583}
v3.5.6
  1/*
  2 * Copyright (C) 2003 PathScale, Inc.
  3 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  4 * Licensed under the GPL
  5 */
  6
  7
  8#include <linux/personality.h>
  9#include <linux/ptrace.h>
 10#include <linux/kernel.h>
 11#include <asm/unistd.h>
 12#include <asm/uaccess.h>
 13#include <asm/ucontext.h>
 14#include "frame_kern.h"
 15#include "skas.h"
 
 16
 17#ifdef CONFIG_X86_32
 18
 19/*
 20 * FPU tag word conversions.
 21 */
 22
 23static 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
 37static 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
 45#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16)
 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
 82static 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
115static 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
149extern int have_fpx_regs;
150
151#endif
152
153static int copy_sc_from_user(struct pt_regs *regs,
154			     struct sigcontext __user *from)
155{
156	struct sigcontext sc;
157	int err, pid;
158
159	/* Always make any pending restarted system calls return -EINTR */
160	current_thread_info()->restart_block.fn = do_no_restart_syscall;
161
162	err = copy_from_user(&sc, from, sizeof(sc));
163	if (err)
164		return err;
165
166#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
167
168#ifdef CONFIG_X86_32
169	GETREG(GS, gs);
170	GETREG(FS, fs);
171	GETREG(ES, es);
172	GETREG(DS, ds);
173#endif
174	GETREG(DI, di);
175	GETREG(SI, si);
176	GETREG(BP, bp);
177	GETREG(SP, sp);
178	GETREG(BX, bx);
179	GETREG(DX, dx);
180	GETREG(CX, cx);
181	GETREG(AX, ax);
182	GETREG(IP, ip);
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
195	GETREG(CS, cs);
196	GETREG(EFLAGS, flags);
197#ifdef CONFIG_X86_32
198	GETREG(SS, ss);
199#endif
200
201#undef GETREG
202
203	pid = userspace_pid[current_thread_info()->cpu];
204#ifdef CONFIG_X86_32
205	if (have_fpx_regs) {
206		struct user_fxsr_struct fpx;
207
208		err = copy_from_user(&fpx,
209			&((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
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
218		err = restore_fpx_registers(pid, (unsigned long *) &fpx);
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		}
225	} else
226#endif
227	{
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
235		err = restore_fp_registers(pid, (unsigned long *) &fp);
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		}
242	}
243	return 0;
244}
245
246static int copy_sc_to_user(struct sigcontext __user *to,
247			   struct _fpstate __user *to_fp, struct pt_regs *regs,
248			   unsigned long mask)
249{
250	struct sigcontext sc;
251	struct faultinfo * fi = &current->thread.arch.faultinfo;
252	int err, pid;
253	memset(&sc, 0, sizeof(struct sigcontext));
254
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
282	sc.cr2 = fi->cr2;
283	sc.err = fi->error_code;
284	sc.trapno = fi->trap_no;
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;
294	sc.fpstate = to_fp;
295
296	err = copy_to_user(to, &sc, sizeof(struct sigcontext));
297	if (err)
298		return 1;
299
300	pid = userspace_pid[current_thread_info()->cpu];
301
302#ifdef CONFIG_X86_32
303	if (have_fpx_regs) {
304		struct user_fxsr_struct fpx;
305
306		err = save_fpx_registers(pid, (unsigned long *) &fpx);
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;
325	} else
326#endif
327	{
328		struct user_i387_struct fp;
329
330		err = save_fp_registers(pid, (unsigned long *) &fp);
331		if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
332			return 1;
333	}
334
335	return 0;
336}
337
338#ifdef CONFIG_X86_32
339static int copy_ucontext_to_user(struct ucontext __user *uc,
340				 struct _fpstate __user *fp, sigset_t *set,
341				 unsigned long sp)
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);
348	err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs, 0);
349	err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
350	return err;
351}
352
353struct sigframe
354{
355	char __user *pretcode;
356	int sig;
357	struct sigcontext sc;
358	struct _fpstate fpstate;
359	unsigned long extramask[_NSIG_WORDS-1];
360	char retcode[8];
361};
362
363struct rt_sigframe
364{
365	char __user *pretcode;
366	int sig;
367	struct siginfo __user *pinfo;
368	void __user *puc;
369	struct siginfo info;
370	struct ucontext uc;
371	struct _fpstate fpstate;
372	char retcode[8];
373};
374
375int 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;
380	void __user *restorer;
381	int err = 0;
382
383	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
384	stack_top = ((stack_top + 4) & -16UL) - 4;
385	frame = (struct sigframe __user *) stack_top - 1;
386	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
387		return 1;
388
389	restorer = frame->retcode;
390	if (ka->sa.sa_flags & SA_RESTORER)
391		restorer = ka->sa.sa_restorer;
392
393	err |= __put_user(restorer, &frame->pretcode);
394	err |= __put_user(sig, &frame->sig);
395	err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
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
411	if (err)
412		return err;
413
414	PT_REGS_SP(regs) = (unsigned long) frame;
415	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
416	PT_REGS_AX(regs) = (unsigned long) sig;
417	PT_REGS_DX(regs) = (unsigned long) 0;
418	PT_REGS_CX(regs) = (unsigned long) 0;
419
420	if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
421		ptrace_notify(SIGTRAP);
422	return 0;
423}
424
425int 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;
430	void __user *restorer;
431	int err = 0;
432
433	stack_top &= -8UL;
434	frame = (struct rt_sigframe __user *) stack_top - 1;
435	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
436		return 1;
437
438	restorer = frame->retcode;
439	if (ka->sa.sa_flags & SA_RESTORER)
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,
448					PT_REGS_SP(regs));
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
461	if (err)
462		return err;
463
464	PT_REGS_SP(regs) = (unsigned long) frame;
465	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
466	PT_REGS_AX(regs) = (unsigned long) sig;
467	PT_REGS_DX(regs) = (unsigned long) &frame->info;
468	PT_REGS_CX(regs) = (unsigned long) &frame->uc;
469
470	if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
471		ptrace_notify(SIGTRAP);
472	return 0;
473}
474
475long sys_sigreturn(struct pt_regs *regs)
476{
477	unsigned long sp = PT_REGS_SP(&current->thread.regs);
478	struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
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
485	if (copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) ||
486	    copy_from_user(&set.sig[1], extramask, sig_size))
487		goto segfault;
488
489	set_current_blocked(&set);
490
491	if (copy_sc_from_user(&current->thread.regs, sc))
492		goto segfault;
493
494	/* Avoid ERESTART handling */
495	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
496	return PT_REGS_SYSCALL_RET(&current->thread.regs);
497
498 segfault:
499	force_sig(SIGSEGV, current);
500	return 0;
501}
502
503#else
504
505struct rt_sigframe
506{
507	char __user *pretcode;
508	struct ucontext uc;
509	struct siginfo info;
510	struct _fpstate fpstate;
511};
512
513int setup_signal_stack_si(unsigned long stack_top, int sig,
514			  struct k_sigaction *ka, struct pt_regs * regs,
515			  siginfo_t *info, sigset_t *set)
516{
517	struct rt_sigframe __user *frame;
518	int err = 0;
519	struct task_struct *me = current;
520
521	frame = (struct rt_sigframe __user *)
522		round_down(stack_top - sizeof(struct rt_sigframe), 16);
523	/* Subtract 128 for a red zone and 8 for proper alignment */
524	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
525
526	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
527		goto out;
528
529	if (ka->sa.sa_flags & SA_SIGINFO) {
530		err |= copy_siginfo_to_user(&frame->info, info);
531		if (err)
532			goto out;
533	}
534
535	/* Create the ucontext.  */
536	err |= __put_user(0, &frame->uc.uc_flags);
537	err |= __put_user(0, &frame->uc.uc_link);
538	err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
539	err |= __put_user(sas_ss_flags(PT_REGS_SP(regs)),
540			  &frame->uc.uc_stack.ss_flags);
541	err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
542	err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
543			       set->sig[0]);
544	err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
 
 
 
545	if (sizeof(*set) == 16) {
546		err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
547		err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
548	}
549	else
550		err |= __copy_to_user(&frame->uc.uc_sigmask, set,
551				      sizeof(*set));
552
553	/*
554	 * Set up to return from userspace.  If provided, use a stub
555	 * already in userspace.
556	 */
557	/* x86-64 should always use SA_RESTORER. */
558	if (ka->sa.sa_flags & SA_RESTORER)
559		err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
 
560	else
561		/* could use a vstub here */
562		return err;
563
564	if (err)
565		return err;
566
567	/* Set up registers for signal handler */
568	{
569		struct exec_domain *ed = current_thread_info()->exec_domain;
570		if (unlikely(ed && ed->signal_invmap && sig < 32))
571			sig = ed->signal_invmap[sig];
572	}
573
574	PT_REGS_SP(regs) = (unsigned long) frame;
575	PT_REGS_DI(regs) = sig;
576	/* In case the signal handler was declared without prototypes */
577	PT_REGS_AX(regs) = 0;
578
579	/*
580	 * This also works for non SA_SIGINFO handlers because they expect the
581	 * next argument after the signal number on the stack.
582	 */
583	PT_REGS_SI(regs) = (unsigned long) &frame->info;
584	PT_REGS_DX(regs) = (unsigned long) &frame->uc;
585	PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
586 out:
587	return err;
588}
589#endif
590
591long sys_rt_sigreturn(struct pt_regs *regs)
592{
593	unsigned long sp = PT_REGS_SP(&current->thread.regs);
594	struct rt_sigframe __user *frame =
595		(struct rt_sigframe __user *)(sp - sizeof(long));
596	struct ucontext __user *uc = &frame->uc;
597	sigset_t set;
598
599	if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
600		goto segfault;
601
602	set_current_blocked(&set);
603
604	if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
605		goto segfault;
606
607	/* Avoid ERESTART handling */
608	PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
609	return PT_REGS_SYSCALL_RET(&current->thread.regs);
610
611 segfault:
612	force_sig(SIGSEGV, current);
613	return 0;
614}
615
616#ifdef CONFIG_X86_32
617long ptregs_sigreturn(void)
618{
619	return sys_sigreturn(NULL);
620}
621long ptregs_rt_sigreturn(void)
622{
623	return sys_rt_sigreturn(NULL);
624}
625#endif