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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
21
22
23static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
24{
25 unsigned int tmp;
26
27
28 tmp = ~twd;
29 tmp = (tmp | (tmp>>1)) & 0x5555;
30
31 tmp = (tmp | (tmp >> 1)) & 0x3333;
32 tmp = (tmp | (tmp >> 2)) & 0x0f0f;
33 tmp = (tmp | (tmp >> 4)) & 0x00ff;
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;
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;
61 } else {
62 tag = 2;
63 }
64 break;
65 default:
66 if (st->significand[3] & 0x8000) {
67 tag = 0;
68 } else {
69 tag = 2;
70 }
71 break;
72 }
73 } else {
74 tag = 3;
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 err = copy_from_user(&sc, from, sizeof(sc));
160 if (err)
161 return err;
162
163#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
164
165#ifdef CONFIG_X86_32
166 GETREG(GS, gs);
167 GETREG(FS, fs);
168 GETREG(ES, es);
169 GETREG(DS, ds);
170#endif
171 GETREG(DI, di);
172 GETREG(SI, si);
173 GETREG(BP, bp);
174 GETREG(SP, sp);
175 GETREG(BX, bx);
176 GETREG(DX, dx);
177 GETREG(CX, cx);
178 GETREG(AX, ax);
179 GETREG(IP, ip);
180
181#ifdef CONFIG_X86_64
182 GETREG(R8, r8);
183 GETREG(R9, r9);
184 GETREG(R10, r10);
185 GETREG(R11, r11);
186 GETREG(R12, r12);
187 GETREG(R13, r13);
188 GETREG(R14, r14);
189 GETREG(R15, r15);
190#endif
191
192 GETREG(CS, cs);
193 GETREG(EFLAGS, flags);
194#ifdef CONFIG_X86_32
195 GETREG(SS, ss);
196#endif
197
198#undef GETREG
199
200 pid = userspace_pid[current_thread_info()->cpu];
201#ifdef CONFIG_X86_32
202 if (have_fpx_regs) {
203 struct user_fxsr_struct fpx;
204
205 err = copy_from_user(&fpx,
206 &((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0],
207 sizeof(struct user_fxsr_struct));
208 if (err)
209 return 1;
210
211 err = convert_fxsr_from_user(&fpx, sc.fpstate);
212 if (err)
213 return 1;
214
215 err = restore_fpx_registers(pid, (unsigned long *) &fpx);
216 if (err < 0) {
217 printk(KERN_ERR "copy_sc_from_user - "
218 "restore_fpx_registers failed, errno = %d\n",
219 -err);
220 return 1;
221 }
222 } else
223#endif
224 {
225 struct user_i387_struct fp;
226
227 err = copy_from_user(&fp, sc.fpstate,
228 sizeof(struct user_i387_struct));
229 if (err)
230 return 1;
231
232 err = restore_fp_registers(pid, (unsigned long *) &fp);
233 if (err < 0) {
234 printk(KERN_ERR "copy_sc_from_user - "
235 "restore_fp_registers failed, errno = %d\n",
236 -err);
237 return 1;
238 }
239 }
240 return 0;
241}
242
243static int copy_sc_to_user(struct sigcontext __user *to,
244 struct _fpstate __user *to_fp, struct pt_regs *regs,
245 unsigned long mask)
246{
247 struct sigcontext sc;
248 struct faultinfo * fi = ¤t->thread.arch.faultinfo;
249 int err, pid;
250 memset(&sc, 0, sizeof(struct sigcontext));
251
252#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
253
254#ifdef CONFIG_X86_32
255 PUTREG(GS, gs);
256 PUTREG(FS, fs);
257 PUTREG(ES, es);
258 PUTREG(DS, ds);
259#endif
260 PUTREG(DI, di);
261 PUTREG(SI, si);
262 PUTREG(BP, bp);
263 PUTREG(SP, sp);
264 PUTREG(BX, bx);
265 PUTREG(DX, dx);
266 PUTREG(CX, cx);
267 PUTREG(AX, ax);
268#ifdef CONFIG_X86_64
269 PUTREG(R8, r8);
270 PUTREG(R9, r9);
271 PUTREG(R10, r10);
272 PUTREG(R11, r11);
273 PUTREG(R12, r12);
274 PUTREG(R13, r13);
275 PUTREG(R14, r14);
276 PUTREG(R15, r15);
277#endif
278
279 sc.cr2 = fi->cr2;
280 sc.err = fi->error_code;
281 sc.trapno = fi->trap_no;
282 PUTREG(IP, ip);
283 PUTREG(CS, cs);
284 PUTREG(EFLAGS, flags);
285#ifdef CONFIG_X86_32
286 PUTREG(SP, sp_at_signal);
287 PUTREG(SS, ss);
288#endif
289#undef PUTREG
290 sc.oldmask = mask;
291 sc.fpstate = to_fp;
292
293 err = copy_to_user(to, &sc, sizeof(struct sigcontext));
294 if (err)
295 return 1;
296
297 pid = userspace_pid[current_thread_info()->cpu];
298
299#ifdef CONFIG_X86_32
300 if (have_fpx_regs) {
301 struct user_fxsr_struct fpx;
302
303 err = save_fpx_registers(pid, (unsigned long *) &fpx);
304 if (err < 0){
305 printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
306 "failed, errno = %d\n", err);
307 return 1;
308 }
309
310 err = convert_fxsr_to_user(to_fp, &fpx);
311 if (err)
312 return 1;
313
314 err |= __put_user(fpx.swd, &to_fp->status);
315 err |= __put_user(X86_FXSR_MAGIC, &to_fp->magic);
316 if (err)
317 return 1;
318
319 if (copy_to_user(&to_fp->_fxsr_env[0], &fpx,
320 sizeof(struct user_fxsr_struct)))
321 return 1;
322 } else
323#endif
324 {
325 struct user_i387_struct fp;
326
327 err = save_fp_registers(pid, (unsigned long *) &fp);
328 if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
329 return 1;
330 }
331
332 return 0;
333}
334
335#ifdef CONFIG_X86_32
336static int copy_ucontext_to_user(struct ucontext __user *uc,
337 struct _fpstate __user *fp, sigset_t *set,
338 unsigned long sp)
339{
340 int err = 0;
341
342 err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
343 err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
344 err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
345 err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, 0);
346 err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
347 return err;
348}
349
350struct sigframe
351{
352 char __user *pretcode;
353 int sig;
354 struct sigcontext sc;
355 struct _fpstate fpstate;
356 unsigned long extramask[_NSIG_WORDS-1];
357 char retcode[8];
358};
359
360struct rt_sigframe
361{
362 char __user *pretcode;
363 int sig;
364 struct siginfo __user *pinfo;
365 void __user *puc;
366 struct siginfo info;
367 struct ucontext uc;
368 struct _fpstate fpstate;
369 char retcode[8];
370};
371
372int setup_signal_stack_sc(unsigned long stack_top, int sig,
373 struct k_sigaction *ka, struct pt_regs *regs,
374 sigset_t *mask)
375{
376 struct sigframe __user *frame;
377 void __user *restorer;
378 int err = 0;
379
380
381 stack_top = ((stack_top + 4) & -16UL) - 4;
382 frame = (struct sigframe __user *) stack_top - 1;
383 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
384 return 1;
385
386 restorer = frame->retcode;
387 if (ka->sa.sa_flags & SA_RESTORER)
388 restorer = ka->sa.sa_restorer;
389
390 err |= __put_user(restorer, &frame->pretcode);
391 err |= __put_user(sig, &frame->sig);
392 err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
393 if (_NSIG_WORDS > 1)
394 err |= __copy_to_user(&frame->extramask, &mask->sig[1],
395 sizeof(frame->extramask));
396
397
398
399
400
401
402
403
404 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
405 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
406 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
407
408 if (err)
409 return err;
410
411 PT_REGS_SP(regs) = (unsigned long) frame;
412 PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
413 PT_REGS_EAX(regs) = (unsigned long) sig;
414 PT_REGS_EDX(regs) = (unsigned long) 0;
415 PT_REGS_ECX(regs) = (unsigned long) 0;
416
417 if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
418 ptrace_notify(SIGTRAP);
419 return 0;
420}
421
422int setup_signal_stack_si(unsigned long stack_top, int sig,
423 struct k_sigaction *ka, struct pt_regs *regs,
424 siginfo_t *info, sigset_t *mask)
425{
426 struct rt_sigframe __user *frame;
427 void __user *restorer;
428 int err = 0;
429
430 stack_top &= -8UL;
431 frame = (struct rt_sigframe __user *) stack_top - 1;
432 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
433 return 1;
434
435 restorer = frame->retcode;
436 if (ka->sa.sa_flags & SA_RESTORER)
437 restorer = ka->sa.sa_restorer;
438
439 err |= __put_user(restorer, &frame->pretcode);
440 err |= __put_user(sig, &frame->sig);
441 err |= __put_user(&frame->info, &frame->pinfo);
442 err |= __put_user(&frame->uc, &frame->puc);
443 err |= copy_siginfo_to_user(&frame->info, info);
444 err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
445 PT_REGS_SP(regs));
446
447
448
449
450
451
452
453
454 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
455 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
456 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
457
458 if (err)
459 return err;
460
461 PT_REGS_SP(regs) = (unsigned long) frame;
462 PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
463 PT_REGS_EAX(regs) = (unsigned long) sig;
464 PT_REGS_EDX(regs) = (unsigned long) &frame->info;
465 PT_REGS_ECX(regs) = (unsigned long) &frame->uc;
466
467 if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
468 ptrace_notify(SIGTRAP);
469 return 0;
470}
471
472long sys_sigreturn(struct pt_regs *regs)
473{
474 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
475 struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
476 sigset_t set;
477 struct sigcontext __user *sc = &frame->sc;
478 unsigned long __user *oldmask = &sc->oldmask;
479 unsigned long __user *extramask = frame->extramask;
480 int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
481
482 if (copy_from_user(&set.sig[0], oldmask, sizeof(set.sig[0])) ||
483 copy_from_user(&set.sig[1], extramask, sig_size))
484 goto segfault;
485
486 sigdelsetmask(&set, ~_BLOCKABLE);
487 set_current_blocked(&set);
488
489 if (copy_sc_from_user(¤t->thread.regs, sc))
490 goto segfault;
491
492
493 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
494 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
495
496 segfault:
497 force_sig(SIGSEGV, current);
498 return 0;
499}
500
501#else
502
503struct rt_sigframe
504{
505 char __user *pretcode;
506 struct ucontext uc;
507 struct siginfo info;
508 struct _fpstate fpstate;
509};
510
511int setup_signal_stack_si(unsigned long stack_top, int sig,
512 struct k_sigaction *ka, struct pt_regs * regs,
513 siginfo_t *info, sigset_t *set)
514{
515 struct rt_sigframe __user *frame;
516 int err = 0;
517 struct task_struct *me = current;
518
519 frame = (struct rt_sigframe __user *)
520 round_down(stack_top - sizeof(struct rt_sigframe), 16);
521
522 frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
523
524 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
525 goto out;
526
527 if (ka->sa.sa_flags & SA_SIGINFO) {
528 err |= copy_siginfo_to_user(&frame->info, info);
529 if (err)
530 goto out;
531 }
532
533
534 err |= __put_user(0, &frame->uc.uc_flags);
535 err |= __put_user(0, &frame->uc.uc_link);
536 err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
537 err |= __put_user(sas_ss_flags(PT_REGS_SP(regs)),
538 &frame->uc.uc_stack.ss_flags);
539 err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
540 err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
541 set->sig[0]);
542 err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
543 if (sizeof(*set) == 16) {
544 __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
545 __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
546 }
547 else
548 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
549 sizeof(*set));
550
551
552
553
554
555
556 if (ka->sa.sa_flags & SA_RESTORER)
557 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
558 else
559
560 return err;
561
562 if (err)
563 return err;
564
565
566 {
567 struct exec_domain *ed = current_thread_info()->exec_domain;
568 if (unlikely(ed && ed->signal_invmap && sig < 32))
569 sig = ed->signal_invmap[sig];
570 }
571
572 PT_REGS_SP(regs) = (unsigned long) frame;
573 PT_REGS_RDI(regs) = sig;
574
575 PT_REGS_RAX(regs) = 0;
576
577
578
579
580
581 PT_REGS_RSI(regs) = (unsigned long) &frame->info;
582 PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
583 PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
584 out:
585 return err;
586}
587#endif
588
589long sys_rt_sigreturn(struct pt_regs *regs)
590{
591 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
592 struct rt_sigframe __user *frame =
593 (struct rt_sigframe __user *)(sp - sizeof(long));
594 struct ucontext __user *uc = &frame->uc;
595 sigset_t set;
596
597 if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
598 goto segfault;
599
600 sigdelsetmask(&set, ~_BLOCKABLE);
601 set_current_blocked(&set);
602
603 if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
604 goto segfault;
605
606
607 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
608 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
609
610 segfault:
611 force_sig(SIGSEGV, current);
612 return 0;
613}
614
615#ifdef CONFIG_X86_32
616long ptregs_sigreturn(void)
617{
618 return sys_sigreturn(NULL);
619}
620long ptregs_rt_sigreturn(void)
621{
622 return sys_rt_sigreturn(NULL);
623}
624#endif
625
