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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 <linux/syscalls.h>
12#include <asm/unistd.h>
13#include <linux/uaccess.h>
14#include <asm/ucontext.h>
15#include <frame_kern.h>
16#include <registers.h>
17#include <skas.h>
18
19#include <linux/regset.h>
20#include <asm/sigframe.h>
21
22#ifdef CONFIG_X86_32
23struct _xstate_64 {
24 struct _fpstate_64 fpstate;
25 struct _header xstate_hdr;
26 struct _ymmh_state ymmh;
27 /* New processor state extensions go here: */
28};
29#else
30#define _xstate_64 _xstate
31#endif
32
33static int copy_sc_from_user(struct pt_regs *regs,
34 struct sigcontext __user *from)
35{
36 struct _xstate_64 __user *from_fp64;
37 struct sigcontext sc;
38 int err;
39
40 /* Always make any pending restarted system calls return -EINTR */
41 current->restart_block.fn = do_no_restart_syscall;
42
43 err = copy_from_user(&sc, from, sizeof(sc));
44 if (err)
45 return err;
46
47#define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname
48
49#ifdef CONFIG_X86_32
50 GETREG(GS, gs);
51 GETREG(FS, fs);
52 GETREG(ES, es);
53 GETREG(DS, ds);
54#endif
55 GETREG(DI, di);
56 GETREG(SI, si);
57 GETREG(BP, bp);
58 GETREG(SP, sp);
59 GETREG(BX, bx);
60 GETREG(DX, dx);
61 GETREG(CX, cx);
62 GETREG(AX, ax);
63 GETREG(IP, ip);
64
65#ifdef CONFIG_X86_64
66 GETREG(R8, r8);
67 GETREG(R9, r9);
68 GETREG(R10, r10);
69 GETREG(R11, r11);
70 GETREG(R12, r12);
71 GETREG(R13, r13);
72 GETREG(R14, r14);
73 GETREG(R15, r15);
74#endif
75
76 GETREG(CS, cs);
77 GETREG(EFLAGS, flags);
78#ifdef CONFIG_X86_32
79 GETREG(SS, ss);
80#endif
81
82#undef GETREG
83
84#ifdef CONFIG_X86_32
85 from_fp64 = ((void __user *)sc.fpstate) +
86 offsetof(struct _fpstate_32, _fxsr_env);
87#else
88 from_fp64 = (void __user *)sc.fpstate;
89#endif
90
91 err = copy_from_user(regs->regs.fp, from_fp64, host_fp_size);
92 if (err)
93 return 1;
94
95#ifdef CONFIG_X86_32
96 /* Data is duplicated and this copy is the important one */
97 err = copy_regset_from_user(current,
98 task_user_regset_view(current),
99 REGSET_FP_LEGACY, 0,
100 sizeof(struct user_i387_struct),
101 (void __user *)sc.fpstate);
102 if (err < 0)
103 return err;
104#endif
105
106 return 0;
107}
108
109static int copy_sc_to_user(struct sigcontext __user *to,
110 struct _xstate __user *to_fp, struct pt_regs *regs,
111 unsigned long mask)
112{
113 struct _xstate_64 __user *to_fp64;
114 struct sigcontext sc;
115 struct faultinfo * fi = ¤t->thread.arch.faultinfo;
116 int err;
117 memset(&sc, 0, sizeof(struct sigcontext));
118
119#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
120
121#ifdef CONFIG_X86_32
122 PUTREG(GS, gs);
123 PUTREG(FS, fs);
124 PUTREG(ES, es);
125 PUTREG(DS, ds);
126#endif
127 PUTREG(DI, di);
128 PUTREG(SI, si);
129 PUTREG(BP, bp);
130 PUTREG(SP, sp);
131 PUTREG(BX, bx);
132 PUTREG(DX, dx);
133 PUTREG(CX, cx);
134 PUTREG(AX, ax);
135#ifdef CONFIG_X86_64
136 PUTREG(R8, r8);
137 PUTREG(R9, r9);
138 PUTREG(R10, r10);
139 PUTREG(R11, r11);
140 PUTREG(R12, r12);
141 PUTREG(R13, r13);
142 PUTREG(R14, r14);
143 PUTREG(R15, r15);
144#endif
145
146 sc.cr2 = fi->cr2;
147 sc.err = fi->error_code;
148 sc.trapno = fi->trap_no;
149 PUTREG(IP, ip);
150 PUTREG(CS, cs);
151 PUTREG(EFLAGS, flags);
152#ifdef CONFIG_X86_32
153 PUTREG(SP, sp_at_signal);
154 PUTREG(SS, ss);
155#endif
156#undef PUTREG
157 sc.oldmask = mask;
158 sc.fpstate = (unsigned long)to_fp;
159
160 err = copy_to_user(to, &sc, sizeof(struct sigcontext));
161 if (err)
162 return 1;
163
164#ifdef CONFIG_X86_32
165 err = copy_regset_to_user(current,
166 task_user_regset_view(current),
167 REGSET_FP_LEGACY, 0,
168 sizeof(struct _fpstate_32), to_fp);
169 if (err < 0)
170 return err;
171
172 __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
173
174 BUILD_BUG_ON(offsetof(struct _xstate, xstate_hdr) !=
175 offsetof(struct _xstate_64, xstate_hdr) +
176 offsetof(struct _fpstate_32, _fxsr_env));
177 to_fp64 = (void __user *)to_fp +
178 offsetof(struct _fpstate_32, _fxsr_env);
179#else
180 to_fp64 = to_fp;
181#endif /* CONFIG_X86_32 */
182
183 if (copy_to_user(to_fp64, regs->regs.fp, host_fp_size))
184 return 1;
185
186 /*
187 * Put magic/size values for userspace. We do not bother to verify them
188 * later on, however, userspace needs them should it try to read the
189 * XSTATE data. And ptrace does not fill in these parts.
190 *
191 * Skip this if we do not have an XSTATE frame.
192 */
193 if (host_fp_size <= sizeof(to_fp64->fpstate))
194 return 0;
195
196 BUILD_BUG_ON(sizeof(int) != FP_XSTATE_MAGIC2_SIZE);
197#ifdef CONFIG_X86_32
198 __put_user(offsetof(struct _fpstate_32, _fxsr_env) +
199 host_fp_size + FP_XSTATE_MAGIC2_SIZE,
200 &to_fp64->fpstate.sw_reserved.extended_size);
201#else
202 __put_user(host_fp_size + FP_XSTATE_MAGIC2_SIZE,
203 &to_fp64->fpstate.sw_reserved.extended_size);
204#endif
205 __put_user(host_fp_size, &to_fp64->fpstate.sw_reserved.xstate_size);
206
207 __put_user(FP_XSTATE_MAGIC1, &to_fp64->fpstate.sw_reserved.magic1);
208 __put_user(FP_XSTATE_MAGIC2,
209 (int __user *)((void __user *)to_fp64 + host_fp_size));
210
211 return 0;
212}
213
214#ifdef CONFIG_X86_32
215static int copy_ucontext_to_user(struct ucontext __user *uc,
216 struct _xstate __user *fp, sigset_t *set,
217 unsigned long sp)
218{
219 int err = 0;
220
221 err |= __save_altstack(&uc->uc_stack, sp);
222 err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, 0);
223 err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
224 return err;
225}
226
227int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
228 struct pt_regs *regs, sigset_t *mask)
229{
230 size_t math_size = offsetof(struct _fpstate_32, _fxsr_env) +
231 host_fp_size + FP_XSTATE_MAGIC2_SIZE;
232 struct sigframe __user *frame;
233 void __user *restorer;
234 int err = 0, sig = ksig->sig;
235 unsigned long fp_to;
236
237 /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
238 stack_top = ((stack_top + 4) & -16UL) - 4;
239 frame = (struct sigframe __user *) stack_top - 1;
240 if (!access_ok(frame, sizeof(*frame)))
241 return 1;
242
243 /* Add required space for math frame */
244 frame = (struct sigframe __user *)((unsigned long)frame - math_size);
245
246 restorer = frame->retcode;
247 if (ksig->ka.sa.sa_flags & SA_RESTORER)
248 restorer = ksig->ka.sa.sa_restorer;
249
250 err |= __put_user(restorer, (void __user * __user *)&frame->pretcode);
251 err |= __put_user(sig, &frame->sig);
252
253 fp_to = (unsigned long)frame + sizeof(*frame);
254
255 err |= copy_sc_to_user(&frame->sc,
256 (struct _xstate __user *)fp_to,
257 regs, mask->sig[0]);
258 if (_NSIG_WORDS > 1)
259 err |= __copy_to_user(&frame->extramask, &mask->sig[1],
260 sizeof(frame->extramask));
261
262 /*
263 * This is popl %eax ; movl $,%eax ; int $0x80
264 *
265 * WE DO NOT USE IT ANY MORE! It's only left here for historical
266 * reasons and because gdb uses it as a signature to notice
267 * signal handler stack frames.
268 */
269 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
270 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
271 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
272
273 if (err)
274 return err;
275
276 PT_REGS_SP(regs) = (unsigned long) frame;
277 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
278 PT_REGS_AX(regs) = (unsigned long) sig;
279 PT_REGS_DX(regs) = (unsigned long) 0;
280 PT_REGS_CX(regs) = (unsigned long) 0;
281 return 0;
282}
283
284int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
285 struct pt_regs *regs, sigset_t *mask)
286{
287 size_t math_size = offsetof(struct _fpstate_32, _fxsr_env) +
288 host_fp_size + FP_XSTATE_MAGIC2_SIZE;
289 struct rt_sigframe __user *frame;
290 void __user *restorer;
291 int err = 0, sig = ksig->sig;
292 unsigned long fp_to;
293
294 stack_top &= -8UL;
295 frame = (struct rt_sigframe __user *) stack_top - 1;
296 if (!access_ok(frame, sizeof(*frame)))
297 return 1;
298
299 /* Add required space for math frame */
300 frame = (struct rt_sigframe __user *)((unsigned long)frame - math_size);
301
302 restorer = frame->retcode;
303 if (ksig->ka.sa.sa_flags & SA_RESTORER)
304 restorer = ksig->ka.sa.sa_restorer;
305
306 err |= __put_user(restorer, (void __user * __user *)&frame->pretcode);
307 err |= __put_user(sig, &frame->sig);
308 err |= __put_user(&frame->info, (void __user * __user *)&frame->pinfo);
309 err |= __put_user(&frame->uc, (void __user * __user *)&frame->puc);
310 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
311
312 fp_to = (unsigned long)frame + sizeof(*frame);
313
314 err |= copy_ucontext_to_user(&frame->uc, (struct _xstate __user *)fp_to,
315 mask, PT_REGS_SP(regs));
316
317 /*
318 * This is movl $,%eax ; int $0x80
319 *
320 * WE DO NOT USE IT ANY MORE! It's only left here for historical
321 * reasons and because gdb uses it as a signature to notice
322 * signal handler stack frames.
323 */
324 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
325 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
326 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
327
328 if (err)
329 return err;
330
331 PT_REGS_SP(regs) = (unsigned long) frame;
332 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
333 PT_REGS_AX(regs) = (unsigned long) sig;
334 PT_REGS_DX(regs) = (unsigned long) &frame->info;
335 PT_REGS_CX(regs) = (unsigned long) &frame->uc;
336 return 0;
337}
338
339SYSCALL_DEFINE0(sigreturn)
340{
341 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
342 struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
343 sigset_t set;
344 struct sigcontext __user *sc = &frame->sc;
345 int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
346
347 if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) ||
348 copy_from_user(&set.sig[1], frame->extramask, sig_size))
349 goto segfault;
350
351 set_current_blocked(&set);
352
353 if (copy_sc_from_user(¤t->thread.regs, sc))
354 goto segfault;
355
356 /* Avoid ERESTART handling */
357 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
358 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
359
360 segfault:
361 force_sig(SIGSEGV);
362 return 0;
363}
364
365#else
366
367int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
368 struct pt_regs *regs, sigset_t *set)
369{
370 unsigned long math_size = host_fp_size + FP_XSTATE_MAGIC2_SIZE;
371 struct rt_sigframe __user *frame;
372 int err = 0, sig = ksig->sig;
373 unsigned long fp_to;
374
375 frame = (void __user *)stack_top - sizeof(struct rt_sigframe);
376
377 /* Add required space for math frame */
378 frame = (void __user *)((unsigned long)frame - math_size);
379
380 /* ABI requires 16 byte boundary alignment */
381 frame = (void __user *)round_down((unsigned long)frame, 16);
382
383 /* Subtract 128 for a red zone and 8 for proper alignment */
384 frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
385
386 if (!access_ok(frame, sizeof(*frame) + math_size))
387 goto out;
388
389 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
390 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
391 if (err)
392 goto out;
393 }
394
395 /* Create the ucontext. */
396 err |= __put_user(0, &frame->uc.uc_flags);
397 err |= __put_user(NULL, &frame->uc.uc_link);
398 err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
399
400 fp_to = (unsigned long)frame + sizeof(*frame);
401
402 err |= copy_sc_to_user(&frame->uc.uc_mcontext,
403 (struct _xstate __user *)fp_to,
404 regs, set->sig[0]);
405
406 err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
407 if (sizeof(*set) == 16) {
408 err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
409 err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
410 }
411 else
412 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
413 sizeof(*set));
414
415 /*
416 * Set up to return from userspace. If provided, use a stub
417 * already in userspace.
418 */
419 /* x86-64 should always use SA_RESTORER. */
420 if (ksig->ka.sa.sa_flags & SA_RESTORER)
421 err |= __put_user((void __user *)ksig->ka.sa.sa_restorer,
422 &frame->pretcode);
423 else
424 /* could use a vstub here */
425 return err;
426
427 if (err)
428 return err;
429
430 PT_REGS_SP(regs) = (unsigned long) frame;
431 PT_REGS_DI(regs) = sig;
432 /* In case the signal handler was declared without prototypes */
433 PT_REGS_AX(regs) = 0;
434
435 /*
436 * This also works for non SA_SIGINFO handlers because they expect the
437 * next argument after the signal number on the stack.
438 */
439 PT_REGS_SI(regs) = (unsigned long) &frame->info;
440 PT_REGS_DX(regs) = (unsigned long) &frame->uc;
441 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
442 out:
443 return err;
444}
445#endif
446
447SYSCALL_DEFINE0(rt_sigreturn)
448{
449 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
450 struct rt_sigframe __user *frame =
451 (struct rt_sigframe __user *)(sp - sizeof(long));
452 struct ucontext __user *uc = &frame->uc;
453 sigset_t set;
454
455 if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
456 goto segfault;
457
458 set_current_blocked(&set);
459
460 if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
461 goto segfault;
462
463 /* Avoid ERESTART handling */
464 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
465 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
466
467 segfault:
468 force_sig(SIGSEGV);
469 return 0;
470}
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 <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->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, (void *)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 err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
229 sizeof(struct _xstate));
230 if (err)
231 return 1;
232 }
233 return 0;
234}
235
236static int copy_sc_to_user(struct sigcontext __user *to,
237 struct _xstate __user *to_fp, struct pt_regs *regs,
238 unsigned long mask)
239{
240 struct sigcontext sc;
241 struct faultinfo * fi = ¤t->thread.arch.faultinfo;
242 int err, pid;
243 memset(&sc, 0, sizeof(struct sigcontext));
244
245#define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno]
246
247#ifdef CONFIG_X86_32
248 PUTREG(GS, gs);
249 PUTREG(FS, fs);
250 PUTREG(ES, es);
251 PUTREG(DS, ds);
252#endif
253 PUTREG(DI, di);
254 PUTREG(SI, si);
255 PUTREG(BP, bp);
256 PUTREG(SP, sp);
257 PUTREG(BX, bx);
258 PUTREG(DX, dx);
259 PUTREG(CX, cx);
260 PUTREG(AX, ax);
261#ifdef CONFIG_X86_64
262 PUTREG(R8, r8);
263 PUTREG(R9, r9);
264 PUTREG(R10, r10);
265 PUTREG(R11, r11);
266 PUTREG(R12, r12);
267 PUTREG(R13, r13);
268 PUTREG(R14, r14);
269 PUTREG(R15, r15);
270#endif
271
272 sc.cr2 = fi->cr2;
273 sc.err = fi->error_code;
274 sc.trapno = fi->trap_no;
275 PUTREG(IP, ip);
276 PUTREG(CS, cs);
277 PUTREG(EFLAGS, flags);
278#ifdef CONFIG_X86_32
279 PUTREG(SP, sp_at_signal);
280 PUTREG(SS, ss);
281#endif
282#undef PUTREG
283 sc.oldmask = mask;
284 sc.fpstate = (unsigned long)to_fp;
285
286 err = copy_to_user(to, &sc, sizeof(struct sigcontext));
287 if (err)
288 return 1;
289
290 pid = userspace_pid[current_thread_info()->cpu];
291
292#ifdef CONFIG_X86_32
293 if (have_fpx_regs) {
294 struct user_fxsr_struct fpx;
295
296 err = save_fpx_registers(pid, (unsigned long *) &fpx);
297 if (err < 0){
298 printk(KERN_ERR "copy_sc_to_user - save_fpx_registers "
299 "failed, errno = %d\n", err);
300 return 1;
301 }
302
303 err = convert_fxsr_to_user(&to_fp->fpstate, &fpx);
304 if (err)
305 return 1;
306
307 err |= __put_user(fpx.swd, &to_fp->fpstate.status);
308 err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
309 if (err)
310 return 1;
311
312 if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx,
313 sizeof(struct user_fxsr_struct)))
314 return 1;
315 } else
316#endif
317 {
318 if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
319 return 1;
320 }
321
322 return 0;
323}
324
325#ifdef CONFIG_X86_32
326static int copy_ucontext_to_user(struct ucontext __user *uc,
327 struct _xstate __user *fp, sigset_t *set,
328 unsigned long sp)
329{
330 int err = 0;
331
332 err |= __save_altstack(&uc->uc_stack, sp);
333 err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, 0);
334 err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
335 return err;
336}
337
338struct sigframe
339{
340 char __user *pretcode;
341 int sig;
342 struct sigcontext sc;
343 struct _xstate fpstate;
344 unsigned long extramask[_NSIG_WORDS-1];
345 char retcode[8];
346};
347
348struct rt_sigframe
349{
350 char __user *pretcode;
351 int sig;
352 struct siginfo __user *pinfo;
353 void __user *puc;
354 struct siginfo info;
355 struct ucontext uc;
356 struct _xstate fpstate;
357 char retcode[8];
358};
359
360int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
361 struct pt_regs *regs, sigset_t *mask)
362{
363 struct sigframe __user *frame;
364 void __user *restorer;
365 int err = 0, sig = ksig->sig;
366
367 /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
368 stack_top = ((stack_top + 4) & -16UL) - 4;
369 frame = (struct sigframe __user *) stack_top - 1;
370 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
371 return 1;
372
373 restorer = frame->retcode;
374 if (ksig->ka.sa.sa_flags & SA_RESTORER)
375 restorer = ksig->ka.sa.sa_restorer;
376
377 err |= __put_user(restorer, &frame->pretcode);
378 err |= __put_user(sig, &frame->sig);
379 err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
380 if (_NSIG_WORDS > 1)
381 err |= __copy_to_user(&frame->extramask, &mask->sig[1],
382 sizeof(frame->extramask));
383
384 /*
385 * This is popl %eax ; movl $,%eax ; int $0x80
386 *
387 * WE DO NOT USE IT ANY MORE! It's only left here for historical
388 * reasons and because gdb uses it as a signature to notice
389 * signal handler stack frames.
390 */
391 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
392 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
393 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
394
395 if (err)
396 return err;
397
398 PT_REGS_SP(regs) = (unsigned long) frame;
399 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
400 PT_REGS_AX(regs) = (unsigned long) sig;
401 PT_REGS_DX(regs) = (unsigned long) 0;
402 PT_REGS_CX(regs) = (unsigned long) 0;
403 return 0;
404}
405
406int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
407 struct pt_regs *regs, sigset_t *mask)
408{
409 struct rt_sigframe __user *frame;
410 void __user *restorer;
411 int err = 0, sig = ksig->sig;
412
413 stack_top &= -8UL;
414 frame = (struct rt_sigframe __user *) stack_top - 1;
415 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
416 return 1;
417
418 restorer = frame->retcode;
419 if (ksig->ka.sa.sa_flags & SA_RESTORER)
420 restorer = ksig->ka.sa.sa_restorer;
421
422 err |= __put_user(restorer, &frame->pretcode);
423 err |= __put_user(sig, &frame->sig);
424 err |= __put_user(&frame->info, &frame->pinfo);
425 err |= __put_user(&frame->uc, &frame->puc);
426 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
427 err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
428 PT_REGS_SP(regs));
429
430 /*
431 * This is movl $,%eax ; int $0x80
432 *
433 * WE DO NOT USE IT ANY MORE! It's only left here for historical
434 * reasons and because gdb uses it as a signature to notice
435 * signal handler stack frames.
436 */
437 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
438 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
439 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
440
441 if (err)
442 return err;
443
444 PT_REGS_SP(regs) = (unsigned long) frame;
445 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
446 PT_REGS_AX(regs) = (unsigned long) sig;
447 PT_REGS_DX(regs) = (unsigned long) &frame->info;
448 PT_REGS_CX(regs) = (unsigned long) &frame->uc;
449 return 0;
450}
451
452long sys_sigreturn(void)
453{
454 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
455 struct sigframe __user *frame = (struct sigframe __user *)(sp - 8);
456 sigset_t set;
457 struct sigcontext __user *sc = &frame->sc;
458 int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
459
460 if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) ||
461 copy_from_user(&set.sig[1], frame->extramask, sig_size))
462 goto segfault;
463
464 set_current_blocked(&set);
465
466 if (copy_sc_from_user(¤t->thread.regs, sc))
467 goto segfault;
468
469 /* Avoid ERESTART handling */
470 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
471 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
472
473 segfault:
474 force_sig(SIGSEGV, current);
475 return 0;
476}
477
478#else
479
480struct rt_sigframe
481{
482 char __user *pretcode;
483 struct ucontext uc;
484 struct siginfo info;
485 struct _xstate fpstate;
486};
487
488int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
489 struct pt_regs *regs, sigset_t *set)
490{
491 struct rt_sigframe __user *frame;
492 int err = 0, sig = ksig->sig;
493 unsigned long fp_to;
494
495 frame = (struct rt_sigframe __user *)
496 round_down(stack_top - sizeof(struct rt_sigframe), 16);
497 /* Subtract 128 for a red zone and 8 for proper alignment */
498 frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
499
500 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
501 goto out;
502
503 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
504 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
505 if (err)
506 goto out;
507 }
508
509 /* Create the ucontext. */
510 err |= __put_user(0, &frame->uc.uc_flags);
511 err |= __put_user(0, &frame->uc.uc_link);
512 err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
513 err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
514 set->sig[0]);
515
516 fp_to = (unsigned long)&frame->fpstate;
517
518 err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
519 if (sizeof(*set) == 16) {
520 err |= __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
521 err |= __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
522 }
523 else
524 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
525 sizeof(*set));
526
527 /*
528 * Set up to return from userspace. If provided, use a stub
529 * already in userspace.
530 */
531 /* x86-64 should always use SA_RESTORER. */
532 if (ksig->ka.sa.sa_flags & SA_RESTORER)
533 err |= __put_user((void *)ksig->ka.sa.sa_restorer,
534 &frame->pretcode);
535 else
536 /* could use a vstub here */
537 return err;
538
539 if (err)
540 return err;
541
542 PT_REGS_SP(regs) = (unsigned long) frame;
543 PT_REGS_DI(regs) = sig;
544 /* In case the signal handler was declared without prototypes */
545 PT_REGS_AX(regs) = 0;
546
547 /*
548 * This also works for non SA_SIGINFO handlers because they expect the
549 * next argument after the signal number on the stack.
550 */
551 PT_REGS_SI(regs) = (unsigned long) &frame->info;
552 PT_REGS_DX(regs) = (unsigned long) &frame->uc;
553 PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler;
554 out:
555 return err;
556}
557#endif
558
559long sys_rt_sigreturn(void)
560{
561 unsigned long sp = PT_REGS_SP(¤t->thread.regs);
562 struct rt_sigframe __user *frame =
563 (struct rt_sigframe __user *)(sp - sizeof(long));
564 struct ucontext __user *uc = &frame->uc;
565 sigset_t set;
566
567 if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
568 goto segfault;
569
570 set_current_blocked(&set);
571
572 if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext))
573 goto segfault;
574
575 /* Avoid ERESTART handling */
576 PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1;
577 return PT_REGS_SYSCALL_RET(¤t->thread.regs);
578
579 segfault:
580 force_sig(SIGSEGV, current);
581 return 0;
582}