Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f67aa2ff AV |
2 | * Copyright (C) 2003 PathScale, Inc. |
3 | * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) | |
1da177e4 LT |
4 | * Licensed under the GPL |
5 | */ | |
6 | ||
f67aa2ff AV |
7 | |
8 | #include <linux/personality.h> | |
7796931f | 9 | #include <linux/ptrace.h> |
f67aa2ff | 10 | #include <linux/kernel.h> |
323ced96 | 11 | #include <linux/syscalls.h> |
7796931f | 12 | #include <asm/unistd.h> |
7c0f6ba6 | 13 | #include <linux/uaccess.h> |
7796931f | 14 | #include <asm/ucontext.h> |
37185b33 | 15 | #include <frame_kern.h> |
dbba7f70 | 16 | #include <registers.h> |
37185b33 | 17 | #include <skas.h> |
1da177e4 | 18 | |
f67aa2ff AV |
19 | #ifdef CONFIG_X86_32 |
20 | ||
a5f6096c JD |
21 | /* |
22 | * FPU tag word conversions. | |
23 | */ | |
24 | ||
25 | static inline unsigned short twd_i387_to_fxsr(unsigned short twd) | |
26 | { | |
27 | unsigned int tmp; /* to avoid 16 bit prefixes in the code */ | |
28 | ||
29 | /* Transform each pair of bits into 01 (valid) or 00 (empty) */ | |
30 | tmp = ~twd; | |
31 | tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ | |
32 | /* and move the valid bits to the lower byte. */ | |
33 | tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ | |
34 | tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ | |
35 | tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */ | |
36 | return tmp; | |
37 | } | |
38 | ||
39 | static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave) | |
40 | { | |
41 | struct _fpxreg *st = NULL; | |
42 | unsigned long twd = (unsigned long) fxsave->twd; | |
43 | unsigned long tag; | |
44 | unsigned long ret = 0xffff0000; | |
45 | int i; | |
46 | ||
497888cf | 47 | #define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16) |
a5f6096c JD |
48 | |
49 | for (i = 0; i < 8; i++) { | |
50 | if (twd & 0x1) { | |
51 | st = (struct _fpxreg *) FPREG_ADDR(fxsave, i); | |
52 | ||
53 | switch (st->exponent & 0x7fff) { | |
54 | case 0x7fff: | |
55 | tag = 2; /* Special */ | |
56 | break; | |
57 | case 0x0000: | |
58 | if ( !st->significand[0] && | |
59 | !st->significand[1] && | |
60 | !st->significand[2] && | |
61 | !st->significand[3] ) { | |
62 | tag = 1; /* Zero */ | |
63 | } else { | |
64 | tag = 2; /* Special */ | |
65 | } | |
66 | break; | |
67 | default: | |
68 | if (st->significand[3] & 0x8000) { | |
69 | tag = 0; /* Valid */ | |
70 | } else { | |
71 | tag = 2; /* Special */ | |
72 | } | |
73 | break; | |
74 | } | |
75 | } else { | |
76 | tag = 3; /* Empty */ | |
77 | } | |
78 | ret |= (tag << (2 * i)); | |
79 | twd = twd >> 1; | |
80 | } | |
81 | return ret; | |
82 | } | |
83 | ||
84 | static int convert_fxsr_to_user(struct _fpstate __user *buf, | |
85 | struct user_fxsr_struct *fxsave) | |
86 | { | |
87 | unsigned long env[7]; | |
88 | struct _fpreg __user *to; | |
89 | struct _fpxreg *from; | |
90 | int i; | |
91 | ||
92 | env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul; | |
93 | env[1] = (unsigned long)fxsave->swd | 0xffff0000ul; | |
94 | env[2] = twd_fxsr_to_i387(fxsave); | |
95 | env[3] = fxsave->fip; | |
96 | env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16); | |
97 | env[5] = fxsave->foo; | |
98 | env[6] = fxsave->fos; | |
99 | ||
100 | if (__copy_to_user(buf, env, 7 * sizeof(unsigned long))) | |
101 | return 1; | |
102 | ||
103 | to = &buf->_st[0]; | |
104 | from = (struct _fpxreg *) &fxsave->st_space[0]; | |
105 | for (i = 0; i < 8; i++, to++, from++) { | |
106 | unsigned long __user *t = (unsigned long __user *)to; | |
107 | unsigned long *f = (unsigned long *)from; | |
108 | ||
109 | if (__put_user(*f, t) || | |
110 | __put_user(*(f + 1), t + 1) || | |
111 | __put_user(from->exponent, &to->exponent)) | |
112 | return 1; | |
113 | } | |
114 | return 0; | |
115 | } | |
116 | ||
117 | static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave, | |
118 | struct _fpstate __user *buf) | |
119 | { | |
120 | unsigned long env[7]; | |
121 | struct _fpxreg *to; | |
122 | struct _fpreg __user *from; | |
123 | int i; | |
124 | ||
125 | if (copy_from_user( env, buf, 7 * sizeof(long))) | |
126 | return 1; | |
127 | ||
128 | fxsave->cwd = (unsigned short)(env[0] & 0xffff); | |
129 | fxsave->swd = (unsigned short)(env[1] & 0xffff); | |
130 | fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff)); | |
131 | fxsave->fip = env[3]; | |
132 | fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16); | |
133 | fxsave->fcs = (env[4] & 0xffff); | |
134 | fxsave->foo = env[5]; | |
135 | fxsave->fos = env[6]; | |
136 | ||
137 | to = (struct _fpxreg *) &fxsave->st_space[0]; | |
138 | from = &buf->_st[0]; | |
139 | for (i = 0; i < 8; i++, to++, from++) { | |
140 | unsigned long *t = (unsigned long *)to; | |
141 | unsigned long __user *f = (unsigned long __user *)from; | |
142 | ||
143 | if (__get_user(*t, f) || | |
144 | __get_user(*(t + 1), f + 1) || | |
145 | __get_user(to->exponent, &from->exponent)) | |
146 | return 1; | |
147 | } | |
148 | return 0; | |
149 | } | |
150 | ||
151 | extern int have_fpx_regs; | |
152 | ||
f67aa2ff AV |
153 | #endif |
154 | ||
77bf4400 JD |
155 | static int copy_sc_from_user(struct pt_regs *regs, |
156 | struct sigcontext __user *from) | |
1da177e4 | 157 | { |
a5f6096c | 158 | struct sigcontext sc; |
158a6b91 | 159 | int err; |
1da177e4 | 160 | |
3b7d15bd | 161 | /* Always make any pending restarted system calls return -EINTR */ |
f56141e3 | 162 | current->restart_block.fn = do_no_restart_syscall; |
3b7d15bd | 163 | |
1da177e4 | 164 | err = copy_from_user(&sc, from, sizeof(sc)); |
ba180fd4 | 165 | if (err) |
5d86456d | 166 | return err; |
1da177e4 | 167 | |
a955bd61 AV |
168 | #define GETREG(regno, regname) regs->regs.gp[HOST_##regno] = sc.regname |
169 | ||
f67aa2ff | 170 | #ifdef CONFIG_X86_32 |
a955bd61 AV |
171 | GETREG(GS, gs); |
172 | GETREG(FS, fs); | |
173 | GETREG(ES, es); | |
174 | GETREG(DS, ds); | |
f67aa2ff | 175 | #endif |
3579a389 AV |
176 | GETREG(DI, di); |
177 | GETREG(SI, si); | |
178 | GETREG(BP, bp); | |
a955bd61 | 179 | GETREG(SP, sp); |
3579a389 AV |
180 | GETREG(BX, bx); |
181 | GETREG(DX, dx); | |
182 | GETREG(CX, cx); | |
183 | GETREG(AX, ax); | |
a955bd61 | 184 | GETREG(IP, ip); |
f67aa2ff AV |
185 | |
186 | #ifdef CONFIG_X86_64 | |
187 | GETREG(R8, r8); | |
188 | GETREG(R9, r9); | |
189 | GETREG(R10, r10); | |
190 | GETREG(R11, r11); | |
191 | GETREG(R12, r12); | |
192 | GETREG(R13, r13); | |
193 | GETREG(R14, r14); | |
194 | GETREG(R15, r15); | |
195 | #endif | |
196 | ||
a955bd61 AV |
197 | GETREG(CS, cs); |
198 | GETREG(EFLAGS, flags); | |
f67aa2ff | 199 | #ifdef CONFIG_X86_32 |
a955bd61 | 200 | GETREG(SS, ss); |
f67aa2ff | 201 | #endif |
a955bd61 AV |
202 | |
203 | #undef GETREG | |
f67aa2ff | 204 | |
f67aa2ff | 205 | #ifdef CONFIG_X86_32 |
a5f6096c JD |
206 | if (have_fpx_regs) { |
207 | struct user_fxsr_struct fpx; | |
158a6b91 | 208 | int pid = userspace_pid[current_thread_info()->cpu]; |
1da177e4 | 209 | |
966c8079 WC |
210 | err = copy_from_user(&fpx, |
211 | &((struct _fpstate __user *)sc.fpstate)->_fxsr_env[0], | |
a5f6096c JD |
212 | sizeof(struct user_fxsr_struct)); |
213 | if (err) | |
214 | return 1; | |
215 | ||
8090bfd2 | 216 | err = convert_fxsr_from_user(&fpx, (void *)sc.fpstate); |
a5f6096c JD |
217 | if (err) |
218 | return 1; | |
219 | ||
a5a678c8 | 220 | err = restore_fpx_registers(pid, (unsigned long *) &fpx); |
a5f6096c JD |
221 | if (err < 0) { |
222 | printk(KERN_ERR "copy_sc_from_user - " | |
223 | "restore_fpx_registers failed, errno = %d\n", | |
224 | -err); | |
225 | return 1; | |
226 | } | |
f67aa2ff AV |
227 | } else |
228 | #endif | |
229 | { | |
6de5a8a5 | 230 | err = copy_from_user(regs->regs.fp, (void *)sc.fpstate, |
b6024b21 | 231 | sizeof(struct _xstate)); |
a5f6096c JD |
232 | if (err) |
233 | return 1; | |
1da177e4 | 234 | } |
5d86456d | 235 | return 0; |
1da177e4 LT |
236 | } |
237 | ||
77bf4400 | 238 | static int copy_sc_to_user(struct sigcontext __user *to, |
b6024b21 | 239 | struct _xstate __user *to_fp, struct pt_regs *regs, |
f67aa2ff | 240 | unsigned long mask) |
1da177e4 | 241 | { |
ba180fd4 | 242 | struct sigcontext sc; |
c578455a | 243 | struct faultinfo * fi = ¤t->thread.arch.faultinfo; |
158a6b91 | 244 | int err; |
a955bd61 | 245 | memset(&sc, 0, sizeof(struct sigcontext)); |
1da177e4 | 246 | |
f67aa2ff AV |
247 | #define PUTREG(regno, regname) sc.regname = regs->regs.gp[HOST_##regno] |
248 | ||
249 | #ifdef CONFIG_X86_32 | |
250 | PUTREG(GS, gs); | |
251 | PUTREG(FS, fs); | |
252 | PUTREG(ES, es); | |
253 | PUTREG(DS, ds); | |
254 | #endif | |
255 | PUTREG(DI, di); | |
256 | PUTREG(SI, si); | |
257 | PUTREG(BP, bp); | |
258 | PUTREG(SP, sp); | |
259 | PUTREG(BX, bx); | |
260 | PUTREG(DX, dx); | |
261 | PUTREG(CX, cx); | |
262 | PUTREG(AX, ax); | |
263 | #ifdef CONFIG_X86_64 | |
264 | PUTREG(R8, r8); | |
265 | PUTREG(R9, r9); | |
266 | PUTREG(R10, r10); | |
267 | PUTREG(R11, r11); | |
268 | PUTREG(R12, r12); | |
269 | PUTREG(R13, r13); | |
270 | PUTREG(R14, r14); | |
271 | PUTREG(R15, r15); | |
272 | #endif | |
273 | ||
ba180fd4 JD |
274 | sc.cr2 = fi->cr2; |
275 | sc.err = fi->error_code; | |
276 | sc.trapno = fi->trap_no; | |
f67aa2ff AV |
277 | PUTREG(IP, ip); |
278 | PUTREG(CS, cs); | |
279 | PUTREG(EFLAGS, flags); | |
280 | #ifdef CONFIG_X86_32 | |
281 | PUTREG(SP, sp_at_signal); | |
282 | PUTREG(SS, ss); | |
283 | #endif | |
284 | #undef PUTREG | |
285 | sc.oldmask = mask; | |
8090bfd2 | 286 | sc.fpstate = (unsigned long)to_fp; |
1da177e4 | 287 | |
f67aa2ff AV |
288 | err = copy_to_user(to, &sc, sizeof(struct sigcontext)); |
289 | if (err) | |
290 | return 1; | |
291 | ||
f67aa2ff | 292 | #ifdef CONFIG_X86_32 |
a5f6096c | 293 | if (have_fpx_regs) { |
158a6b91 | 294 | int pid = userspace_pid[current_thread_info()->cpu]; |
a5f6096c JD |
295 | struct user_fxsr_struct fpx; |
296 | ||
a5a678c8 | 297 | err = save_fpx_registers(pid, (unsigned long *) &fpx); |
a5f6096c JD |
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 | ||
b6024b21 | 304 | err = convert_fxsr_to_user(&to_fp->fpstate, &fpx); |
a5f6096c JD |
305 | if (err) |
306 | return 1; | |
307 | ||
b6024b21 EC |
308 | err |= __put_user(fpx.swd, &to_fp->fpstate.status); |
309 | err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic); | |
a5f6096c JD |
310 | if (err) |
311 | return 1; | |
312 | ||
b6024b21 | 313 | if (copy_to_user(&to_fp->fpstate._fxsr_env[0], &fpx, |
a5f6096c JD |
314 | sizeof(struct user_fxsr_struct))) |
315 | return 1; | |
f67aa2ff AV |
316 | } else |
317 | #endif | |
318 | { | |
b6024b21 | 319 | if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate))) |
a5f6096c JD |
320 | return 1; |
321 | } | |
1da177e4 | 322 | |
f67aa2ff | 323 | return 0; |
1da177e4 | 324 | } |
1da177e4 | 325 | |
f67aa2ff | 326 | #ifdef CONFIG_X86_32 |
ba180fd4 | 327 | static int copy_ucontext_to_user(struct ucontext __user *uc, |
b6024b21 | 328 | struct _xstate __user *fp, sigset_t *set, |
ba180fd4 | 329 | unsigned long sp) |
1da177e4 LT |
330 | { |
331 | int err = 0; | |
332 | ||
c40702c4 | 333 | err |= __save_altstack(&uc->uc_stack, sp); |
f67aa2ff | 334 | err |= copy_sc_to_user(&uc->uc_mcontext, fp, ¤t->thread.regs, 0); |
1da177e4 | 335 | err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set)); |
5d86456d | 336 | return err; |
1da177e4 LT |
337 | } |
338 | ||
339 | struct sigframe | |
340 | { | |
4d338e1a | 341 | char __user *pretcode; |
1da177e4 LT |
342 | int sig; |
343 | struct sigcontext sc; | |
b6024b21 | 344 | struct _xstate fpstate; |
1da177e4 LT |
345 | unsigned long extramask[_NSIG_WORDS-1]; |
346 | char retcode[8]; | |
347 | }; | |
348 | ||
349 | struct rt_sigframe | |
350 | { | |
4d338e1a | 351 | char __user *pretcode; |
1da177e4 | 352 | int sig; |
4d338e1a AV |
353 | struct siginfo __user *pinfo; |
354 | void __user *puc; | |
1da177e4 LT |
355 | struct siginfo info; |
356 | struct ucontext uc; | |
b6024b21 | 357 | struct _xstate fpstate; |
1da177e4 LT |
358 | char retcode[8]; |
359 | }; | |
360 | ||
307627ee RW |
361 | int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig, |
362 | struct pt_regs *regs, sigset_t *mask) | |
1da177e4 LT |
363 | { |
364 | struct sigframe __user *frame; | |
4d338e1a | 365 | void __user *restorer; |
307627ee | 366 | int err = 0, sig = ksig->sig; |
1da177e4 | 367 | |
3896625d JD |
368 | /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */ |
369 | stack_top = ((stack_top + 4) & -16UL) - 4; | |
4d338e1a | 370 | frame = (struct sigframe __user *) stack_top - 1; |
96d4f267 | 371 | if (!access_ok(frame, sizeof(*frame))) |
1da177e4 LT |
372 | return 1; |
373 | ||
4d338e1a | 374 | restorer = frame->retcode; |
307627ee RW |
375 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
376 | restorer = ksig->ka.sa.sa_restorer; | |
1da177e4 LT |
377 | |
378 | err |= __put_user(restorer, &frame->pretcode); | |
379 | err |= __put_user(sig, &frame->sig); | |
f67aa2ff | 380 | err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]); |
1da177e4 LT |
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 | ||
ba180fd4 | 396 | if (err) |
fbe98686 | 397 | return err; |
1da177e4 LT |
398 | |
399 | PT_REGS_SP(regs) = (unsigned long) frame; | |
307627ee | 400 | PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler; |
243412be AV |
401 | PT_REGS_AX(regs) = (unsigned long) sig; |
402 | PT_REGS_DX(regs) = (unsigned long) 0; | |
403 | PT_REGS_CX(regs) = (unsigned long) 0; | |
98c18238 | 404 | return 0; |
1da177e4 LT |
405 | } |
406 | ||
307627ee RW |
407 | int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig, |
408 | struct pt_regs *regs, sigset_t *mask) | |
1da177e4 LT |
409 | { |
410 | struct rt_sigframe __user *frame; | |
4d338e1a | 411 | void __user *restorer; |
307627ee | 412 | int err = 0, sig = ksig->sig; |
1da177e4 LT |
413 | |
414 | stack_top &= -8UL; | |
4d338e1a | 415 | frame = (struct rt_sigframe __user *) stack_top - 1; |
96d4f267 | 416 | if (!access_ok(frame, sizeof(*frame))) |
1da177e4 LT |
417 | return 1; |
418 | ||
4d338e1a | 419 | restorer = frame->retcode; |
307627ee RW |
420 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
421 | restorer = ksig->ka.sa.sa_restorer; | |
1da177e4 LT |
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); | |
307627ee | 427 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
1da177e4 | 428 | err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask, |
fbe98686 | 429 | PT_REGS_SP(regs)); |
1da177e4 LT |
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 | ||
ba180fd4 | 442 | if (err) |
fbe98686 | 443 | return err; |
1da177e4 | 444 | |
fbe98686 | 445 | PT_REGS_SP(regs) = (unsigned long) frame; |
307627ee | 446 | PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler; |
243412be AV |
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; | |
98c18238 | 450 | return 0; |
1da177e4 LT |
451 | } |
452 | ||
323ced96 | 453 | SYSCALL_DEFINE0(sigreturn) |
1da177e4 LT |
454 | { |
455 | unsigned long sp = PT_REGS_SP(¤t->thread.regs); | |
4d338e1a | 456 | struct sigframe __user *frame = (struct sigframe __user *)(sp - 8); |
1da177e4 LT |
457 | sigset_t set; |
458 | struct sigcontext __user *sc = &frame->sc; | |
1da177e4 LT |
459 | int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long); |
460 | ||
de379379 | 461 | if (copy_from_user(&set.sig[0], &sc->oldmask, sizeof(set.sig[0])) || |
8090bfd2 | 462 | copy_from_user(&set.sig[1], frame->extramask, sig_size)) |
1da177e4 LT |
463 | goto segfault; |
464 | ||
78722a44 | 465 | set_current_blocked(&set); |
1da177e4 | 466 | |
ba180fd4 | 467 | if (copy_sc_from_user(¤t->thread.regs, sc)) |
1da177e4 LT |
468 | goto segfault; |
469 | ||
470 | /* Avoid ERESTART handling */ | |
471 | PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; | |
5d86456d | 472 | return PT_REGS_SYSCALL_RET(¤t->thread.regs); |
1da177e4 LT |
473 | |
474 | segfault: | |
3cf5d076 | 475 | force_sig(SIGSEGV); |
1da177e4 LT |
476 | return 0; |
477 | } | |
478 | ||
f67aa2ff AV |
479 | #else |
480 | ||
481 | struct rt_sigframe | |
482 | { | |
483 | char __user *pretcode; | |
484 | struct ucontext uc; | |
485 | struct siginfo info; | |
b6024b21 | 486 | struct _xstate fpstate; |
f67aa2ff AV |
487 | }; |
488 | ||
307627ee RW |
489 | int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig, |
490 | struct pt_regs *regs, sigset_t *set) | |
f67aa2ff AV |
491 | { |
492 | struct rt_sigframe __user *frame; | |
307627ee | 493 | int err = 0, sig = ksig->sig; |
8090bfd2 | 494 | unsigned long fp_to; |
f67aa2ff AV |
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 | ||
96d4f267 | 501 | if (!access_ok(frame, sizeof(*frame))) |
f67aa2ff AV |
502 | goto out; |
503 | ||
307627ee RW |
504 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
505 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); | |
f67aa2ff AV |
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); | |
c40702c4 | 513 | err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs)); |
f67aa2ff AV |
514 | err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs, |
515 | set->sig[0]); | |
8090bfd2 RW |
516 | |
517 | fp_to = (unsigned long)&frame->fpstate; | |
518 | ||
519 | err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate); | |
f67aa2ff | 520 | if (sizeof(*set) == 16) { |
ffc51be8 AV |
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]); | |
f67aa2ff AV |
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. */ | |
307627ee | 533 | if (ksig->ka.sa.sa_flags & SA_RESTORER) |
6c684465 RW |
534 | err |= __put_user((void *)ksig->ka.sa.sa_restorer, |
535 | &frame->pretcode); | |
f67aa2ff AV |
536 | else |
537 | /* could use a vstub here */ | |
538 | return err; | |
539 | ||
540 | if (err) | |
541 | return err; | |
542 | ||
f67aa2ff | 543 | PT_REGS_SP(regs) = (unsigned long) frame; |
243412be | 544 | PT_REGS_DI(regs) = sig; |
f67aa2ff | 545 | /* In case the signal handler was declared without prototypes */ |
243412be | 546 | PT_REGS_AX(regs) = 0; |
f67aa2ff AV |
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 | */ | |
243412be AV |
552 | PT_REGS_SI(regs) = (unsigned long) &frame->info; |
553 | PT_REGS_DX(regs) = (unsigned long) &frame->uc; | |
307627ee | 554 | PT_REGS_IP(regs) = (unsigned long) ksig->ka.sa.sa_handler; |
f67aa2ff AV |
555 | out: |
556 | return err; | |
557 | } | |
558 | #endif | |
559 | ||
323ced96 | 560 | SYSCALL_DEFINE0(rt_sigreturn) |
1da177e4 | 561 | { |
4d338e1a | 562 | unsigned long sp = PT_REGS_SP(¤t->thread.regs); |
ba180fd4 | 563 | struct rt_sigframe __user *frame = |
f67aa2ff | 564 | (struct rt_sigframe __user *)(sp - sizeof(long)); |
1da177e4 | 565 | struct ucontext __user *uc = &frame->uc; |
f67aa2ff | 566 | sigset_t set; |
1da177e4 | 567 | |
f67aa2ff | 568 | if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set))) |
1da177e4 LT |
569 | goto segfault; |
570 | ||
78722a44 | 571 | set_current_blocked(&set); |
1da177e4 | 572 | |
ba180fd4 | 573 | if (copy_sc_from_user(¤t->thread.regs, &uc->uc_mcontext)) |
1da177e4 LT |
574 | goto segfault; |
575 | ||
576 | /* Avoid ERESTART handling */ | |
577 | PT_REGS_SYSCALL_NR(¤t->thread.regs) = -1; | |
5d86456d | 578 | return PT_REGS_SYSCALL_RET(¤t->thread.regs); |
1da177e4 LT |
579 | |
580 | segfault: | |
3cf5d076 | 581 | force_sig(SIGSEGV); |
1da177e4 LT |
582 | return 0; |
583 | } |