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10#include <linux/cache.h>
11#include <linux/sched.h>
12#include <linux/mm.h>
13#include <linux/personality.h>
14#include <linux/smp.h>
15#include <linux/kernel.h>
16#include <linux/signal.h>
17#include <linux/errno.h>
18#include <linux/wait.h>
19#include <linux/ptrace.h>
20#include <linux/unistd.h>
21#include <linux/compiler.h>
22#include <linux/syscalls.h>
23#include <linux/uaccess.h>
24#include <linux/tracehook.h>
25
26#include <asm/abi.h>
27#include <asm/asm.h>
28#include <linux/bitops.h>
29#include <asm/cacheflush.h>
30#include <asm/fpu.h>
31#include <asm/sim.h>
32#include <asm/ucontext.h>
33#include <asm/cpu-features.h>
34#include <asm/war.h>
35
36#include "signal-common.h"
37
38
39
40
41
42
43#if ICACHE_REFILLS_WORKAROUND_WAR == 0
44
45struct sigframe {
46 u32 sf_ass[4];
47 u32 sf_code[2];
48 struct sigcontext sf_sc;
49 sigset_t sf_mask;
50};
51
52struct rt_sigframe {
53 u32 rs_ass[4];
54 u32 rs_code[2];
55 struct siginfo rs_info;
56 struct ucontext rs_uc;
57};
58
59#else
60
61struct sigframe {
62 u32 sf_ass[4];
63 u32 sf_pad[2];
64 struct sigcontext sf_sc;
65 sigset_t sf_mask;
66 u32 sf_code[8] ____cacheline_aligned;
67};
68
69struct rt_sigframe {
70 u32 rs_ass[4];
71 u32 rs_pad[2];
72 struct siginfo rs_info;
73 struct ucontext rs_uc;
74 u32 rs_code[8] ____cacheline_aligned;
75};
76
77#endif
78
79
80
81
82static int protected_save_fp_context(struct sigcontext __user *sc)
83{
84 int err;
85 while (1) {
86 lock_fpu_owner();
87 own_fpu_inatomic(1);
88 err = save_fp_context(sc);
89 unlock_fpu_owner();
90 if (likely(!err))
91 break;
92
93 err = __put_user(0, &sc->sc_fpregs[0]) |
94 __put_user(0, &sc->sc_fpregs[31]) |
95 __put_user(0, &sc->sc_fpc_csr);
96 if (err)
97 break;
98 }
99 return err;
100}
101
102static int protected_restore_fp_context(struct sigcontext __user *sc)
103{
104 int err, tmp;
105 while (1) {
106 lock_fpu_owner();
107 own_fpu_inatomic(0);
108 err = restore_fp_context(sc);
109 unlock_fpu_owner();
110 if (likely(!err))
111 break;
112
113 err = __get_user(tmp, &sc->sc_fpregs[0]) |
114 __get_user(tmp, &sc->sc_fpregs[31]) |
115 __get_user(tmp, &sc->sc_fpc_csr);
116 if (err)
117 break;
118 }
119 return err;
120}
121
122int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
123{
124 int err = 0;
125 int i;
126 unsigned int used_math;
127
128 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
129
130 err |= __put_user(0, &sc->sc_regs[0]);
131 for (i = 1; i < 32; i++)
132 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
133
134#ifdef CONFIG_CPU_HAS_SMARTMIPS
135 err |= __put_user(regs->acx, &sc->sc_acx);
136#endif
137 err |= __put_user(regs->hi, &sc->sc_mdhi);
138 err |= __put_user(regs->lo, &sc->sc_mdlo);
139 if (cpu_has_dsp) {
140 err |= __put_user(mfhi1(), &sc->sc_hi1);
141 err |= __put_user(mflo1(), &sc->sc_lo1);
142 err |= __put_user(mfhi2(), &sc->sc_hi2);
143 err |= __put_user(mflo2(), &sc->sc_lo2);
144 err |= __put_user(mfhi3(), &sc->sc_hi3);
145 err |= __put_user(mflo3(), &sc->sc_lo3);
146 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
147 }
148
149 used_math = !!used_math();
150 err |= __put_user(used_math, &sc->sc_used_math);
151
152 if (used_math) {
153
154
155
156
157 err |= protected_save_fp_context(sc);
158 }
159 return err;
160}
161
162int fpcsr_pending(unsigned int __user *fpcsr)
163{
164 int err, sig = 0;
165 unsigned int csr, enabled;
166
167 err = __get_user(csr, fpcsr);
168 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
169
170
171
172
173 if (csr & enabled) {
174 csr &= ~enabled;
175 err |= __put_user(csr, fpcsr);
176 sig = SIGFPE;
177 }
178 return err ?: sig;
179}
180
181static int
182check_and_restore_fp_context(struct sigcontext __user *sc)
183{
184 int err, sig;
185
186 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
187 if (err > 0)
188 err = 0;
189 err |= protected_restore_fp_context(sc);
190 return err ?: sig;
191}
192
193int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
194{
195 unsigned int used_math;
196 unsigned long treg;
197 int err = 0;
198 int i;
199
200
201 current_thread_info()->restart_block.fn = do_no_restart_syscall;
202
203 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
204
205#ifdef CONFIG_CPU_HAS_SMARTMIPS
206 err |= __get_user(regs->acx, &sc->sc_acx);
207#endif
208 err |= __get_user(regs->hi, &sc->sc_mdhi);
209 err |= __get_user(regs->lo, &sc->sc_mdlo);
210 if (cpu_has_dsp) {
211 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
212 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
213 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
214 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
215 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
216 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
217 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
218 }
219
220 for (i = 1; i < 32; i++)
221 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
222
223 err |= __get_user(used_math, &sc->sc_used_math);
224 conditional_used_math(used_math);
225
226 if (used_math) {
227
228 if (!err)
229 err = check_and_restore_fp_context(sc);
230 } else {
231
232 lose_fpu(0);
233 }
234
235 return err;
236}
237
238void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
239 size_t frame_size)
240{
241 unsigned long sp;
242
243
244 sp = regs->regs[29];
245
246
247
248
249
250
251 sp -= 32;
252
253
254 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
255 sp = current->sas_ss_sp + current->sas_ss_size;
256
257 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
258}
259
260int install_sigtramp(unsigned int __user *tramp, unsigned int syscall)
261{
262 int err;
263
264
265
266
267
268
269
270
271 err = __put_user(0x24020000 + syscall, tramp + 0);
272 err |= __put_user(0x0000000c , tramp + 1);
273 if (ICACHE_REFILLS_WORKAROUND_WAR) {
274 err |= __put_user(0, tramp + 2);
275 err |= __put_user(0, tramp + 3);
276 err |= __put_user(0, tramp + 4);
277 err |= __put_user(0, tramp + 5);
278 err |= __put_user(0, tramp + 6);
279 err |= __put_user(0, tramp + 7);
280 }
281 flush_cache_sigtramp((unsigned long) tramp);
282
283 return err;
284}
285
286
287
288
289
290#ifdef CONFIG_TRAD_SIGNALS
291asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
292{
293 sigset_t newset;
294 sigset_t __user *uset;
295
296 uset = (sigset_t __user *) regs.regs[4];
297 if (copy_from_user(&newset, uset, sizeof(sigset_t)))
298 return -EFAULT;
299 sigdelsetmask(&newset, ~_BLOCKABLE);
300
301 spin_lock_irq(¤t->sighand->siglock);
302 current->saved_sigmask = current->blocked;
303 current->blocked = newset;
304 recalc_sigpending();
305 spin_unlock_irq(¤t->sighand->siglock);
306
307 current->state = TASK_INTERRUPTIBLE;
308 schedule();
309 set_thread_flag(TIF_RESTORE_SIGMASK);
310 return -ERESTARTNOHAND;
311}
312#endif
313
314asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
315{
316 sigset_t newset;
317 sigset_t __user *unewset;
318 size_t sigsetsize;
319
320
321 sigsetsize = regs.regs[5];
322 if (sigsetsize != sizeof(sigset_t))
323 return -EINVAL;
324
325 unewset = (sigset_t __user *) regs.regs[4];
326 if (copy_from_user(&newset, unewset, sizeof(newset)))
327 return -EFAULT;
328 sigdelsetmask(&newset, ~_BLOCKABLE);
329
330 spin_lock_irq(¤t->sighand->siglock);
331 current->saved_sigmask = current->blocked;
332 current->blocked = newset;
333 recalc_sigpending();
334 spin_unlock_irq(¤t->sighand->siglock);
335
336 current->state = TASK_INTERRUPTIBLE;
337 schedule();
338 set_thread_flag(TIF_RESTORE_SIGMASK);
339 return -ERESTARTNOHAND;
340}
341
342#ifdef CONFIG_TRAD_SIGNALS
343SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
344 struct sigaction __user *, oact)
345{
346 struct k_sigaction new_ka, old_ka;
347 int ret;
348 int err = 0;
349
350 if (act) {
351 old_sigset_t mask;
352
353 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
354 return -EFAULT;
355 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
356 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
357 err |= __get_user(mask, &act->sa_mask.sig[0]);
358 if (err)
359 return -EFAULT;
360
361 siginitset(&new_ka.sa.sa_mask, mask);
362 }
363
364 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
365
366 if (!ret && oact) {
367 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
368 return -EFAULT;
369 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
370 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
371 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
372 err |= __put_user(0, &oact->sa_mask.sig[1]);
373 err |= __put_user(0, &oact->sa_mask.sig[2]);
374 err |= __put_user(0, &oact->sa_mask.sig[3]);
375 if (err)
376 return -EFAULT;
377 }
378
379 return ret;
380}
381#endif
382
383asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
384{
385 const stack_t __user *uss = (const stack_t __user *) regs.regs[4];
386 stack_t __user *uoss = (stack_t __user *) regs.regs[5];
387 unsigned long usp = regs.regs[29];
388
389 return do_sigaltstack(uss, uoss, usp);
390}
391
392#ifdef CONFIG_TRAD_SIGNALS
393asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
394{
395 struct sigframe __user *frame;
396 sigset_t blocked;
397 int sig;
398
399 frame = (struct sigframe __user *) regs.regs[29];
400 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
401 goto badframe;
402 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
403 goto badframe;
404
405 sigdelsetmask(&blocked, ~_BLOCKABLE);
406 spin_lock_irq(¤t->sighand->siglock);
407 current->blocked = blocked;
408 recalc_sigpending();
409 spin_unlock_irq(¤t->sighand->siglock);
410
411 sig = restore_sigcontext(®s, &frame->sf_sc);
412 if (sig < 0)
413 goto badframe;
414 else if (sig)
415 force_sig(sig, current);
416
417
418
419
420 __asm__ __volatile__(
421 "move\t$29, %0\n\t"
422 "j\tsyscall_exit"
423 :
424 :"r" (®s));
425
426
427badframe:
428 force_sig(SIGSEGV, current);
429}
430#endif
431
432asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
433{
434 struct rt_sigframe __user *frame;
435 sigset_t set;
436 stack_t st;
437 int sig;
438
439 frame = (struct rt_sigframe __user *) regs.regs[29];
440 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
441 goto badframe;
442 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
443 goto badframe;
444
445 sigdelsetmask(&set, ~_BLOCKABLE);
446 spin_lock_irq(¤t->sighand->siglock);
447 current->blocked = set;
448 recalc_sigpending();
449 spin_unlock_irq(¤t->sighand->siglock);
450
451 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
452 if (sig < 0)
453 goto badframe;
454 else if (sig)
455 force_sig(sig, current);
456
457 if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
458 goto badframe;
459
460
461 do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
462
463
464
465
466 __asm__ __volatile__(
467 "move\t$29, %0\n\t"
468 "j\tsyscall_exit"
469 :
470 :"r" (®s));
471
472
473badframe:
474 force_sig(SIGSEGV, current);
475}
476
477#ifdef CONFIG_TRAD_SIGNALS
478static int setup_frame(struct k_sigaction * ka, struct pt_regs *regs,
479 int signr, sigset_t *set)
480{
481 struct sigframe __user *frame;
482 int err = 0;
483
484 frame = get_sigframe(ka, regs, sizeof(*frame));
485 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
486 goto give_sigsegv;
487
488 err |= install_sigtramp(frame->sf_code, __NR_sigreturn);
489
490 err |= setup_sigcontext(regs, &frame->sf_sc);
491 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
492 if (err)
493 goto give_sigsegv;
494
495
496
497
498
499
500
501
502
503
504
505 regs->regs[ 4] = signr;
506 regs->regs[ 5] = 0;
507 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
508 regs->regs[29] = (unsigned long) frame;
509 regs->regs[31] = (unsigned long) frame->sf_code;
510 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
511
512 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
513 current->comm, current->pid,
514 frame, regs->cp0_epc, regs->regs[31]);
515 return 0;
516
517give_sigsegv:
518 force_sigsegv(signr, current);
519 return -EFAULT;
520}
521#endif
522
523static int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs,
524 int signr, sigset_t *set, siginfo_t *info)
525{
526 struct rt_sigframe __user *frame;
527 int err = 0;
528
529 frame = get_sigframe(ka, regs, sizeof(*frame));
530 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
531 goto give_sigsegv;
532
533 err |= install_sigtramp(frame->rs_code, __NR_rt_sigreturn);
534
535
536 err |= copy_siginfo_to_user(&frame->rs_info, info);
537
538
539 err |= __put_user(0, &frame->rs_uc.uc_flags);
540 err |= __put_user(NULL, &frame->rs_uc.uc_link);
541 err |= __put_user((void __user *)current->sas_ss_sp,
542 &frame->rs_uc.uc_stack.ss_sp);
543 err |= __put_user(sas_ss_flags(regs->regs[29]),
544 &frame->rs_uc.uc_stack.ss_flags);
545 err |= __put_user(current->sas_ss_size,
546 &frame->rs_uc.uc_stack.ss_size);
547 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
548 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
549
550 if (err)
551 goto give_sigsegv;
552
553
554
555
556
557
558
559
560
561
562
563 regs->regs[ 4] = signr;
564 regs->regs[ 5] = (unsigned long) &frame->rs_info;
565 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
566 regs->regs[29] = (unsigned long) frame;
567 regs->regs[31] = (unsigned long) frame->rs_code;
568 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
569
570 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
571 current->comm, current->pid,
572 frame, regs->cp0_epc, regs->regs[31]);
573
574 return 0;
575
576give_sigsegv:
577 force_sigsegv(signr, current);
578 return -EFAULT;
579}
580
581struct mips_abi mips_abi = {
582#ifdef CONFIG_TRAD_SIGNALS
583 .setup_frame = setup_frame,
584#endif
585 .setup_rt_frame = setup_rt_frame,
586 .restart = __NR_restart_syscall
587};
588
589static int handle_signal(unsigned long sig, siginfo_t *info,
590 struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
591{
592 int ret;
593
594 switch(regs->regs[0]) {
595 case ERESTART_RESTARTBLOCK:
596 case ERESTARTNOHAND:
597 regs->regs[2] = EINTR;
598 break;
599 case ERESTARTSYS:
600 if (!(ka->sa.sa_flags & SA_RESTART)) {
601 regs->regs[2] = EINTR;
602 break;
603 }
604
605 case ERESTARTNOINTR:
606 regs->regs[7] = regs->regs[26];
607 regs->cp0_epc -= 8;
608 }
609
610 regs->regs[0] = 0;
611
612 if (sig_uses_siginfo(ka))
613 ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
614 else
615 ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
616
617 spin_lock_irq(¤t->sighand->siglock);
618 sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask);
619 if (!(ka->sa.sa_flags & SA_NODEFER))
620 sigaddset(¤t->blocked, sig);
621 recalc_sigpending();
622 spin_unlock_irq(¤t->sighand->siglock);
623
624 return ret;
625}
626
627static void do_signal(struct pt_regs *regs)
628{
629 struct k_sigaction ka;
630 sigset_t *oldset;
631 siginfo_t info;
632 int signr;
633
634
635
636
637
638
639 if (!user_mode(regs))
640 return;
641
642 if (test_thread_flag(TIF_RESTORE_SIGMASK))
643 oldset = ¤t->saved_sigmask;
644 else
645 oldset = ¤t->blocked;
646
647 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
648 if (signr > 0) {
649
650 if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
651
652
653
654
655
656
657 if (test_thread_flag(TIF_RESTORE_SIGMASK))
658 clear_thread_flag(TIF_RESTORE_SIGMASK);
659 }
660
661 return;
662 }
663
664
665
666
667
668
669 if (regs->regs[0]) {
670 if (regs->regs[2] == ERESTARTNOHAND ||
671 regs->regs[2] == ERESTARTSYS ||
672 regs->regs[2] == ERESTARTNOINTR) {
673 regs->regs[7] = regs->regs[26];
674 regs->cp0_epc -= 8;
675 }
676 if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
677 regs->regs[2] = current->thread.abi->restart;
678 regs->regs[7] = regs->regs[26];
679 regs->cp0_epc -= 4;
680 }
681 regs->regs[0] = 0;
682 }
683
684
685
686
687
688 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
689 clear_thread_flag(TIF_RESTORE_SIGMASK);
690 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
691 }
692}
693
694
695
696
697
698asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
699 __u32 thread_info_flags)
700{
701
702 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
703 do_signal(regs);
704
705 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
706 clear_thread_flag(TIF_NOTIFY_RESUME);
707 tracehook_notify_resume(regs);
708 if (current->replacement_session_keyring)
709 key_replace_session_keyring();
710 }
711}
712