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1/*
2 * arch/sparc64/kernel/signal.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
6 * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
7 * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
8 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 */
10
11#ifdef CONFIG_COMPAT
12#include <linux/compat.h> /* for compat_old_sigset_t */
13#endif
14#include <linux/sched.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/tracehook.h>
21#include <linux/unistd.h>
22#include <linux/mm.h>
23#include <linux/tty.h>
24#include <linux/binfmts.h>
25#include <linux/bitops.h>
26#include <linux/context_tracking.h>
27
28#include <asm/uaccess.h>
29#include <asm/ptrace.h>
30#include <asm/pgtable.h>
31#include <asm/fpumacro.h>
32#include <asm/uctx.h>
33#include <asm/siginfo.h>
34#include <asm/visasm.h>
35#include <asm/switch_to.h>
36#include <asm/cacheflush.h>
37
38#include "entry.h"
39#include "systbls.h"
40#include "sigutil.h"
41
42/* {set, get}context() needed for 64-bit SparcLinux userland. */
43asmlinkage void sparc64_set_context(struct pt_regs *regs)
44{
45 struct ucontext __user *ucp = (struct ucontext __user *)
46 regs->u_regs[UREG_I0];
47 enum ctx_state prev_state = exception_enter();
48 mc_gregset_t __user *grp;
49 unsigned long pc, npc, tstate;
50 unsigned long fp, i7;
51 unsigned char fenab;
52 int err;
53
54 flush_user_windows();
55 if (get_thread_wsaved() ||
56 (((unsigned long)ucp) & (sizeof(unsigned long)-1)) ||
57 (!__access_ok(ucp, sizeof(*ucp))))
58 goto do_sigsegv;
59 grp = &ucp->uc_mcontext.mc_gregs;
60 err = __get_user(pc, &((*grp)[MC_PC]));
61 err |= __get_user(npc, &((*grp)[MC_NPC]));
62 if (err || ((pc | npc) & 3))
63 goto do_sigsegv;
64 if (regs->u_regs[UREG_I1]) {
65 sigset_t set;
66
67 if (_NSIG_WORDS == 1) {
68 if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
69 goto do_sigsegv;
70 } else {
71 if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
72 goto do_sigsegv;
73 }
74 set_current_blocked(&set);
75 }
76 if (test_thread_flag(TIF_32BIT)) {
77 pc &= 0xffffffff;
78 npc &= 0xffffffff;
79 }
80 regs->tpc = pc;
81 regs->tnpc = npc;
82 err |= __get_user(regs->y, &((*grp)[MC_Y]));
83 err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
84 regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
85 regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
86 err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
87 err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
88 err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
89 err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
90 err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
91 err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
92
93 /* Skip %g7 as that's the thread register in userspace. */
94
95 err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
96 err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
97 err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
98 err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
99 err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
100 err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
101 err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
102 err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
103
104 err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
105 err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
106 err |= __put_user(fp,
107 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
108 err |= __put_user(i7,
109 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
110
111 err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
112 if (fenab) {
113 unsigned long *fpregs = current_thread_info()->fpregs;
114 unsigned long fprs;
115
116 fprs_write(0);
117 err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
118 if (fprs & FPRS_DL)
119 err |= copy_from_user(fpregs,
120 &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
121 (sizeof(unsigned int) * 32));
122 if (fprs & FPRS_DU)
123 err |= copy_from_user(fpregs+16,
124 ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
125 (sizeof(unsigned int) * 32));
126 err |= __get_user(current_thread_info()->xfsr[0],
127 &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
128 err |= __get_user(current_thread_info()->gsr[0],
129 &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
130 regs->tstate &= ~TSTATE_PEF;
131 }
132 if (err)
133 goto do_sigsegv;
134out:
135 exception_exit(prev_state);
136 return;
137do_sigsegv:
138 force_sig(SIGSEGV, current);
139 goto out;
140}
141
142asmlinkage void sparc64_get_context(struct pt_regs *regs)
143{
144 struct ucontext __user *ucp = (struct ucontext __user *)
145 regs->u_regs[UREG_I0];
146 enum ctx_state prev_state = exception_enter();
147 mc_gregset_t __user *grp;
148 mcontext_t __user *mcp;
149 unsigned long fp, i7;
150 unsigned char fenab;
151 int err;
152
153 synchronize_user_stack();
154 if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
155 goto do_sigsegv;
156
157#if 1
158 fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
159#else
160 fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
161#endif
162
163 mcp = &ucp->uc_mcontext;
164 grp = &mcp->mc_gregs;
165
166 /* Skip over the trap instruction, first. */
167 if (test_thread_flag(TIF_32BIT)) {
168 regs->tpc = (regs->tnpc & 0xffffffff);
169 regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
170 } else {
171 regs->tpc = regs->tnpc;
172 regs->tnpc += 4;
173 }
174 err = 0;
175 if (_NSIG_WORDS == 1)
176 err |= __put_user(current->blocked.sig[0],
177 (unsigned long __user *)&ucp->uc_sigmask);
178 else
179 err |= __copy_to_user(&ucp->uc_sigmask, ¤t->blocked,
180 sizeof(sigset_t));
181
182 err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
183 err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
184 err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
185 err |= __put_user(regs->y, &((*grp)[MC_Y]));
186 err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
187 err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
188 err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
189 err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
190 err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
191 err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
192 err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
193 err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
194 err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
195 err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
196 err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
197 err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
198 err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
199 err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
200 err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
201
202 err |= __get_user(fp,
203 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
204 err |= __get_user(i7,
205 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
206 err |= __put_user(fp, &(mcp->mc_fp));
207 err |= __put_user(i7, &(mcp->mc_i7));
208
209 err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
210 if (fenab) {
211 unsigned long *fpregs = current_thread_info()->fpregs;
212 unsigned long fprs;
213
214 fprs = current_thread_info()->fpsaved[0];
215 if (fprs & FPRS_DL)
216 err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
217 (sizeof(unsigned int) * 32));
218 if (fprs & FPRS_DU)
219 err |= copy_to_user(
220 ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
221 (sizeof(unsigned int) * 32));
222 err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
223 err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
224 err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
225 }
226 if (err)
227 goto do_sigsegv;
228out:
229 exception_exit(prev_state);
230 return;
231do_sigsegv:
232 force_sig(SIGSEGV, current);
233 goto out;
234}
235
236struct rt_signal_frame {
237 struct sparc_stackf ss;
238 siginfo_t info;
239 struct pt_regs regs;
240 __siginfo_fpu_t __user *fpu_save;
241 stack_t stack;
242 sigset_t mask;
243 __siginfo_rwin_t *rwin_save;
244};
245
246void do_rt_sigreturn(struct pt_regs *regs)
247{
248 struct rt_signal_frame __user *sf;
249 unsigned long tpc, tnpc, tstate;
250 __siginfo_fpu_t __user *fpu_save;
251 __siginfo_rwin_t __user *rwin_save;
252 sigset_t set;
253 int err;
254
255 /* Always make any pending restarted system calls return -EINTR */
256 current_thread_info()->restart_block.fn = do_no_restart_syscall;
257
258 synchronize_user_stack ();
259 sf = (struct rt_signal_frame __user *)
260 (regs->u_regs [UREG_FP] + STACK_BIAS);
261
262 /* 1. Make sure we are not getting garbage from the user */
263 if (((unsigned long) sf) & 3)
264 goto segv;
265
266 err = get_user(tpc, &sf->regs.tpc);
267 err |= __get_user(tnpc, &sf->regs.tnpc);
268 if (test_thread_flag(TIF_32BIT)) {
269 tpc &= 0xffffffff;
270 tnpc &= 0xffffffff;
271 }
272 err |= ((tpc | tnpc) & 3);
273
274 /* 2. Restore the state */
275 err |= __get_user(regs->y, &sf->regs.y);
276 err |= __get_user(tstate, &sf->regs.tstate);
277 err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
278
279 /* User can only change condition codes and %asi in %tstate. */
280 regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
281 regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
282
283 err |= __get_user(fpu_save, &sf->fpu_save);
284 if (!err && fpu_save)
285 err |= restore_fpu_state(regs, fpu_save);
286
287 err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
288 err |= restore_altstack(&sf->stack);
289 if (err)
290 goto segv;
291
292 err |= __get_user(rwin_save, &sf->rwin_save);
293 if (!err && rwin_save) {
294 if (restore_rwin_state(rwin_save))
295 goto segv;
296 }
297
298 regs->tpc = tpc;
299 regs->tnpc = tnpc;
300
301 /* Prevent syscall restart. */
302 pt_regs_clear_syscall(regs);
303
304 set_current_blocked(&set);
305 return;
306segv:
307 force_sig(SIGSEGV, current);
308}
309
310/* Checks if the fp is valid */
311static int invalid_frame_pointer(void __user *fp)
312{
313 if (((unsigned long) fp) & 15)
314 return 1;
315 return 0;
316}
317
318static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
319{
320 unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
321
322 /*
323 * If we are on the alternate signal stack and would overflow it, don't.
324 * Return an always-bogus address instead so we will die with SIGSEGV.
325 */
326 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
327 return (void __user *) -1L;
328
329 /* This is the X/Open sanctioned signal stack switching. */
330 sp = sigsp(sp, ksig) - framesize;
331
332 /* Always align the stack frame. This handles two cases. First,
333 * sigaltstack need not be mindful of platform specific stack
334 * alignment. Second, if we took this signal because the stack
335 * is not aligned properly, we'd like to take the signal cleanly
336 * and report that.
337 */
338 sp &= ~15UL;
339
340 return (void __user *) sp;
341}
342
343static inline int
344setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
345{
346 struct rt_signal_frame __user *sf;
347 int wsaved, err, sf_size;
348 void __user *tail;
349
350 /* 1. Make sure everything is clean */
351 synchronize_user_stack();
352 save_and_clear_fpu();
353
354 wsaved = get_thread_wsaved();
355
356 sf_size = sizeof(struct rt_signal_frame);
357 if (current_thread_info()->fpsaved[0] & FPRS_FEF)
358 sf_size += sizeof(__siginfo_fpu_t);
359 if (wsaved)
360 sf_size += sizeof(__siginfo_rwin_t);
361 sf = (struct rt_signal_frame __user *)
362 get_sigframe(ksig, regs, sf_size);
363
364 if (invalid_frame_pointer (sf)) {
365 do_exit(SIGILL); /* won't return, actually */
366 return -EINVAL;
367 }
368
369 tail = (sf + 1);
370
371 /* 2. Save the current process state */
372 err = copy_to_user(&sf->regs, regs, sizeof (*regs));
373
374 if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
375 __siginfo_fpu_t __user *fpu_save = tail;
376 tail += sizeof(__siginfo_fpu_t);
377 err |= save_fpu_state(regs, fpu_save);
378 err |= __put_user((u64)fpu_save, &sf->fpu_save);
379 } else {
380 err |= __put_user(0, &sf->fpu_save);
381 }
382 if (wsaved) {
383 __siginfo_rwin_t __user *rwin_save = tail;
384 tail += sizeof(__siginfo_rwin_t);
385 err |= save_rwin_state(wsaved, rwin_save);
386 err |= __put_user((u64)rwin_save, &sf->rwin_save);
387 set_thread_wsaved(0);
388 } else {
389 err |= __put_user(0, &sf->rwin_save);
390 }
391
392 /* Setup sigaltstack */
393 err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
394
395 err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
396
397 if (!wsaved) {
398 err |= copy_in_user((u64 __user *)sf,
399 (u64 __user *)(regs->u_regs[UREG_FP] +
400 STACK_BIAS),
401 sizeof(struct reg_window));
402 } else {
403 struct reg_window *rp;
404
405 rp = ¤t_thread_info()->reg_window[wsaved - 1];
406 err |= copy_to_user(sf, rp, sizeof(struct reg_window));
407 }
408 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
409 err |= copy_siginfo_to_user(&sf->info, &ksig->info);
410 else {
411 err |= __put_user(ksig->sig, &sf->info.si_signo);
412 err |= __put_user(SI_NOINFO, &sf->info.si_code);
413 }
414 if (err)
415 return err;
416
417 /* 3. signal handler back-trampoline and parameters */
418 regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
419 regs->u_regs[UREG_I0] = ksig->sig;
420 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
421
422 /* The sigcontext is passed in this way because of how it
423 * is defined in GLIBC's /usr/include/bits/sigcontext.h
424 * for sparc64. It includes the 128 bytes of siginfo_t.
425 */
426 regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
427
428 /* 5. signal handler */
429 regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
430 regs->tnpc = (regs->tpc + 4);
431 if (test_thread_flag(TIF_32BIT)) {
432 regs->tpc &= 0xffffffff;
433 regs->tnpc &= 0xffffffff;
434 }
435 /* 4. return to kernel instructions */
436 regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
437 return 0;
438}
439
440static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
441 struct sigaction *sa)
442{
443 switch (regs->u_regs[UREG_I0]) {
444 case ERESTART_RESTARTBLOCK:
445 case ERESTARTNOHAND:
446 no_system_call_restart:
447 regs->u_regs[UREG_I0] = EINTR;
448 regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
449 break;
450 case ERESTARTSYS:
451 if (!(sa->sa_flags & SA_RESTART))
452 goto no_system_call_restart;
453 /* fallthrough */
454 case ERESTARTNOINTR:
455 regs->u_regs[UREG_I0] = orig_i0;
456 regs->tpc -= 4;
457 regs->tnpc -= 4;
458 }
459}
460
461/* Note that 'init' is a special process: it doesn't get signals it doesn't
462 * want to handle. Thus you cannot kill init even with a SIGKILL even by
463 * mistake.
464 */
465static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
466{
467 struct ksignal ksig;
468 int restart_syscall;
469 bool has_handler;
470
471 /* It's a lot of work and synchronization to add a new ptrace
472 * register for GDB to save and restore in order to get
473 * orig_i0 correct for syscall restarts when debugging.
474 *
475 * Although it should be the case that most of the global
476 * registers are volatile across a system call, glibc already
477 * depends upon that fact that we preserve them. So we can't
478 * just use any global register to save away the orig_i0 value.
479 *
480 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
481 * preserved across a system call trap by various pieces of
482 * code in glibc.
483 *
484 * %g7 is used as the "thread register". %g6 is not used in
485 * any fixed manner. %g6 is used as a scratch register and
486 * a compiler temporary, but it's value is never used across
487 * a system call. Therefore %g6 is usable for orig_i0 storage.
488 */
489 if (pt_regs_is_syscall(regs) &&
490 (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
491 regs->u_regs[UREG_G6] = orig_i0;
492
493#ifdef CONFIG_COMPAT
494 if (test_thread_flag(TIF_32BIT)) {
495 extern void do_signal32(struct pt_regs *);
496 do_signal32(regs);
497 return;
498 }
499#endif
500
501 has_handler = get_signal(&ksig);
502
503 restart_syscall = 0;
504 if (pt_regs_is_syscall(regs) &&
505 (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
506 restart_syscall = 1;
507 orig_i0 = regs->u_regs[UREG_G6];
508 }
509
510 if (has_handler) {
511 if (restart_syscall)
512 syscall_restart(orig_i0, regs, &ksig.ka.sa);
513 signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
514 } else {
515 if (restart_syscall) {
516 switch (regs->u_regs[UREG_I0]) {
517 case ERESTARTNOHAND:
518 case ERESTARTSYS:
519 case ERESTARTNOINTR:
520 /* replay the system call when we are done */
521 regs->u_regs[UREG_I0] = orig_i0;
522 regs->tpc -= 4;
523 regs->tnpc -= 4;
524 pt_regs_clear_syscall(regs);
525 case ERESTART_RESTARTBLOCK:
526 regs->u_regs[UREG_G1] = __NR_restart_syscall;
527 regs->tpc -= 4;
528 regs->tnpc -= 4;
529 pt_regs_clear_syscall(regs);
530 }
531 }
532 restore_saved_sigmask();
533 }
534}
535
536void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
537{
538 user_exit();
539 if (thread_info_flags & _TIF_SIGPENDING)
540 do_signal(regs, orig_i0);
541 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
542 clear_thread_flag(TIF_NOTIFY_RESUME);
543 tracehook_notify_resume(regs);
544 }
545 user_enter();
546}
547
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sparc64/kernel/signal.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
7 * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
8 * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
9 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
10 */
11
12#include <linux/sched.h>
13#include <linux/kernel.h>
14#include <linux/signal.h>
15#include <linux/errno.h>
16#include <linux/wait.h>
17#include <linux/ptrace.h>
18#include <linux/tracehook.h>
19#include <linux/unistd.h>
20#include <linux/mm.h>
21#include <linux/tty.h>
22#include <linux/binfmts.h>
23#include <linux/bitops.h>
24#include <linux/context_tracking.h>
25
26#include <linux/uaccess.h>
27#include <asm/ptrace.h>
28#include <asm/pgtable.h>
29#include <asm/fpumacro.h>
30#include <asm/uctx.h>
31#include <asm/siginfo.h>
32#include <asm/visasm.h>
33#include <asm/switch_to.h>
34#include <asm/cacheflush.h>
35
36#include "sigutil.h"
37#include "systbls.h"
38#include "kernel.h"
39#include "entry.h"
40
41/* {set, get}context() needed for 64-bit SparcLinux userland. */
42asmlinkage void sparc64_set_context(struct pt_regs *regs)
43{
44 struct ucontext __user *ucp = (struct ucontext __user *)
45 regs->u_regs[UREG_I0];
46 enum ctx_state prev_state = exception_enter();
47 mc_gregset_t __user *grp;
48 unsigned long pc, npc, tstate;
49 unsigned long fp, i7;
50 unsigned char fenab;
51 int err;
52
53 synchronize_user_stack();
54 if (get_thread_wsaved() ||
55 (((unsigned long)ucp) & (sizeof(unsigned long)-1)) ||
56 (!__access_ok(ucp, sizeof(*ucp))))
57 goto do_sigsegv;
58 grp = &ucp->uc_mcontext.mc_gregs;
59 err = __get_user(pc, &((*grp)[MC_PC]));
60 err |= __get_user(npc, &((*grp)[MC_NPC]));
61 if (err || ((pc | npc) & 3))
62 goto do_sigsegv;
63 if (regs->u_regs[UREG_I1]) {
64 sigset_t set;
65
66 if (_NSIG_WORDS == 1) {
67 if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
68 goto do_sigsegv;
69 } else {
70 if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
71 goto do_sigsegv;
72 }
73 set_current_blocked(&set);
74 }
75 if (test_thread_flag(TIF_32BIT)) {
76 pc &= 0xffffffff;
77 npc &= 0xffffffff;
78 }
79 regs->tpc = pc;
80 regs->tnpc = npc;
81 err |= __get_user(regs->y, &((*grp)[MC_Y]));
82 err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
83 regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
84 regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
85 err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
86 err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
87 err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
88 err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
89 err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
90 err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
91
92 /* Skip %g7 as that's the thread register in userspace. */
93
94 err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
95 err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
96 err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
97 err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
98 err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
99 err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
100 err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
101 err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
102
103 err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
104 err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
105 err |= __put_user(fp,
106 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
107 err |= __put_user(i7,
108 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
109
110 err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
111 if (fenab) {
112 unsigned long *fpregs = current_thread_info()->fpregs;
113 unsigned long fprs;
114
115 fprs_write(0);
116 err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
117 if (fprs & FPRS_DL)
118 err |= copy_from_user(fpregs,
119 &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
120 (sizeof(unsigned int) * 32));
121 if (fprs & FPRS_DU)
122 err |= copy_from_user(fpregs+16,
123 ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
124 (sizeof(unsigned int) * 32));
125 err |= __get_user(current_thread_info()->xfsr[0],
126 &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
127 err |= __get_user(current_thread_info()->gsr[0],
128 &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
129 regs->tstate &= ~TSTATE_PEF;
130 }
131 if (err)
132 goto do_sigsegv;
133out:
134 exception_exit(prev_state);
135 return;
136do_sigsegv:
137 force_sig(SIGSEGV);
138 goto out;
139}
140
141asmlinkage void sparc64_get_context(struct pt_regs *regs)
142{
143 struct ucontext __user *ucp = (struct ucontext __user *)
144 regs->u_regs[UREG_I0];
145 enum ctx_state prev_state = exception_enter();
146 mc_gregset_t __user *grp;
147 mcontext_t __user *mcp;
148 unsigned long fp, i7;
149 unsigned char fenab;
150 int err;
151
152 synchronize_user_stack();
153 if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
154 goto do_sigsegv;
155
156#if 1
157 fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
158#else
159 fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
160#endif
161
162 mcp = &ucp->uc_mcontext;
163 grp = &mcp->mc_gregs;
164
165 /* Skip over the trap instruction, first. */
166 if (test_thread_flag(TIF_32BIT)) {
167 regs->tpc = (regs->tnpc & 0xffffffff);
168 regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
169 } else {
170 regs->tpc = regs->tnpc;
171 regs->tnpc += 4;
172 }
173 err = 0;
174 if (_NSIG_WORDS == 1)
175 err |= __put_user(current->blocked.sig[0],
176 (unsigned long __user *)&ucp->uc_sigmask);
177 else
178 err |= __copy_to_user(&ucp->uc_sigmask, ¤t->blocked,
179 sizeof(sigset_t));
180
181 err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
182 err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
183 err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
184 err |= __put_user(regs->y, &((*grp)[MC_Y]));
185 err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
186 err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
187 err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
188 err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
189 err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
190 err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
191 err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
192 err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
193 err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
194 err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
195 err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
196 err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
197 err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
198 err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
199 err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
200
201 err |= __get_user(fp,
202 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
203 err |= __get_user(i7,
204 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
205 err |= __put_user(fp, &(mcp->mc_fp));
206 err |= __put_user(i7, &(mcp->mc_i7));
207
208 err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
209 if (fenab) {
210 unsigned long *fpregs = current_thread_info()->fpregs;
211 unsigned long fprs;
212
213 fprs = current_thread_info()->fpsaved[0];
214 if (fprs & FPRS_DL)
215 err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
216 (sizeof(unsigned int) * 32));
217 if (fprs & FPRS_DU)
218 err |= copy_to_user(
219 ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
220 (sizeof(unsigned int) * 32));
221 err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
222 err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
223 err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
224 }
225 if (err)
226 goto do_sigsegv;
227out:
228 exception_exit(prev_state);
229 return;
230do_sigsegv:
231 force_sig(SIGSEGV);
232 goto out;
233}
234
235/* Checks if the fp is valid. We always build rt signal frames which
236 * are 16-byte aligned, therefore we can always enforce that the
237 * restore frame has that property as well.
238 */
239static bool invalid_frame_pointer(void __user *fp)
240{
241 if (((unsigned long) fp) & 15)
242 return true;
243 return false;
244}
245
246struct rt_signal_frame {
247 struct sparc_stackf ss;
248 siginfo_t info;
249 struct pt_regs regs;
250 __siginfo_fpu_t __user *fpu_save;
251 stack_t stack;
252 sigset_t mask;
253 __siginfo_rwin_t *rwin_save;
254};
255
256void do_rt_sigreturn(struct pt_regs *regs)
257{
258 unsigned long tpc, tnpc, tstate, ufp;
259 struct rt_signal_frame __user *sf;
260 __siginfo_fpu_t __user *fpu_save;
261 __siginfo_rwin_t __user *rwin_save;
262 sigset_t set;
263 int err;
264
265 /* Always make any pending restarted system calls return -EINTR */
266 current->restart_block.fn = do_no_restart_syscall;
267
268 synchronize_user_stack ();
269 sf = (struct rt_signal_frame __user *)
270 (regs->u_regs [UREG_FP] + STACK_BIAS);
271
272 /* 1. Make sure we are not getting garbage from the user */
273 if (invalid_frame_pointer(sf))
274 goto segv;
275
276 if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
277 goto segv;
278
279 if ((ufp + STACK_BIAS) & 0x7)
280 goto segv;
281
282 err = __get_user(tpc, &sf->regs.tpc);
283 err |= __get_user(tnpc, &sf->regs.tnpc);
284 if (test_thread_flag(TIF_32BIT)) {
285 tpc &= 0xffffffff;
286 tnpc &= 0xffffffff;
287 }
288 err |= ((tpc | tnpc) & 3);
289
290 /* 2. Restore the state */
291 err |= __get_user(regs->y, &sf->regs.y);
292 err |= __get_user(tstate, &sf->regs.tstate);
293 err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
294
295 /* User can only change condition codes and %asi in %tstate. */
296 regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
297 regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
298
299 err |= __get_user(fpu_save, &sf->fpu_save);
300 if (!err && fpu_save)
301 err |= restore_fpu_state(regs, fpu_save);
302
303 err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
304 err |= restore_altstack(&sf->stack);
305 if (err)
306 goto segv;
307
308 err |= __get_user(rwin_save, &sf->rwin_save);
309 if (!err && rwin_save) {
310 if (restore_rwin_state(rwin_save))
311 goto segv;
312 }
313
314 regs->tpc = tpc;
315 regs->tnpc = tnpc;
316
317 /* Prevent syscall restart. */
318 pt_regs_clear_syscall(regs);
319
320 set_current_blocked(&set);
321 return;
322segv:
323 force_sig(SIGSEGV);
324}
325
326static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
327{
328 unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
329
330 /*
331 * If we are on the alternate signal stack and would overflow it, don't.
332 * Return an always-bogus address instead so we will die with SIGSEGV.
333 */
334 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
335 return (void __user *) -1L;
336
337 /* This is the X/Open sanctioned signal stack switching. */
338 sp = sigsp(sp, ksig) - framesize;
339
340 /* Always align the stack frame. This handles two cases. First,
341 * sigaltstack need not be mindful of platform specific stack
342 * alignment. Second, if we took this signal because the stack
343 * is not aligned properly, we'd like to take the signal cleanly
344 * and report that.
345 */
346 sp &= ~15UL;
347
348 return (void __user *) sp;
349}
350
351static inline int
352setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
353{
354 struct rt_signal_frame __user *sf;
355 int wsaved, err, sf_size;
356 void __user *tail;
357
358 /* 1. Make sure everything is clean */
359 synchronize_user_stack();
360 save_and_clear_fpu();
361
362 wsaved = get_thread_wsaved();
363
364 sf_size = sizeof(struct rt_signal_frame);
365 if (current_thread_info()->fpsaved[0] & FPRS_FEF)
366 sf_size += sizeof(__siginfo_fpu_t);
367 if (wsaved)
368 sf_size += sizeof(__siginfo_rwin_t);
369 sf = (struct rt_signal_frame __user *)
370 get_sigframe(ksig, regs, sf_size);
371
372 if (invalid_frame_pointer (sf)) {
373 if (show_unhandled_signals)
374 pr_info("%s[%d] bad frame in setup_rt_frame: %016lx TPC %016lx O7 %016lx\n",
375 current->comm, current->pid, (unsigned long)sf,
376 regs->tpc, regs->u_regs[UREG_I7]);
377 force_sigsegv(ksig->sig);
378 return -EINVAL;
379 }
380
381 tail = (sf + 1);
382
383 /* 2. Save the current process state */
384 err = copy_to_user(&sf->regs, regs, sizeof (*regs));
385
386 if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
387 __siginfo_fpu_t __user *fpu_save = tail;
388 tail += sizeof(__siginfo_fpu_t);
389 err |= save_fpu_state(regs, fpu_save);
390 err |= __put_user((u64)fpu_save, &sf->fpu_save);
391 } else {
392 err |= __put_user(0, &sf->fpu_save);
393 }
394 if (wsaved) {
395 __siginfo_rwin_t __user *rwin_save = tail;
396 tail += sizeof(__siginfo_rwin_t);
397 err |= save_rwin_state(wsaved, rwin_save);
398 err |= __put_user((u64)rwin_save, &sf->rwin_save);
399 set_thread_wsaved(0);
400 } else {
401 err |= __put_user(0, &sf->rwin_save);
402 }
403
404 /* Setup sigaltstack */
405 err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
406
407 err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
408
409 if (!wsaved) {
410 err |= copy_in_user((u64 __user *)sf,
411 (u64 __user *)(regs->u_regs[UREG_FP] +
412 STACK_BIAS),
413 sizeof(struct reg_window));
414 } else {
415 struct reg_window *rp;
416
417 rp = ¤t_thread_info()->reg_window[wsaved - 1];
418 err |= copy_to_user(sf, rp, sizeof(struct reg_window));
419 }
420 if (ksig->ka.sa.sa_flags & SA_SIGINFO)
421 err |= copy_siginfo_to_user(&sf->info, &ksig->info);
422 else {
423 err |= __put_user(ksig->sig, &sf->info.si_signo);
424 err |= __put_user(SI_NOINFO, &sf->info.si_code);
425 }
426 if (err)
427 return err;
428
429 /* 3. signal handler back-trampoline and parameters */
430 regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
431 regs->u_regs[UREG_I0] = ksig->sig;
432 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
433
434 /* The sigcontext is passed in this way because of how it
435 * is defined in GLIBC's /usr/include/bits/sigcontext.h
436 * for sparc64. It includes the 128 bytes of siginfo_t.
437 */
438 regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
439
440 /* 5. signal handler */
441 regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
442 regs->tnpc = (regs->tpc + 4);
443 if (test_thread_flag(TIF_32BIT)) {
444 regs->tpc &= 0xffffffff;
445 regs->tnpc &= 0xffffffff;
446 }
447 /* 4. return to kernel instructions */
448 regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
449 return 0;
450}
451
452static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
453 struct sigaction *sa)
454{
455 switch (regs->u_regs[UREG_I0]) {
456 case ERESTART_RESTARTBLOCK:
457 case ERESTARTNOHAND:
458 no_system_call_restart:
459 regs->u_regs[UREG_I0] = EINTR;
460 regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
461 break;
462 case ERESTARTSYS:
463 if (!(sa->sa_flags & SA_RESTART))
464 goto no_system_call_restart;
465 /* fallthrough */
466 case ERESTARTNOINTR:
467 regs->u_regs[UREG_I0] = orig_i0;
468 regs->tpc -= 4;
469 regs->tnpc -= 4;
470 }
471}
472
473/* Note that 'init' is a special process: it doesn't get signals it doesn't
474 * want to handle. Thus you cannot kill init even with a SIGKILL even by
475 * mistake.
476 */
477static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
478{
479 struct ksignal ksig;
480 int restart_syscall;
481 bool has_handler;
482
483 /* It's a lot of work and synchronization to add a new ptrace
484 * register for GDB to save and restore in order to get
485 * orig_i0 correct for syscall restarts when debugging.
486 *
487 * Although it should be the case that most of the global
488 * registers are volatile across a system call, glibc already
489 * depends upon that fact that we preserve them. So we can't
490 * just use any global register to save away the orig_i0 value.
491 *
492 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
493 * preserved across a system call trap by various pieces of
494 * code in glibc.
495 *
496 * %g7 is used as the "thread register". %g6 is not used in
497 * any fixed manner. %g6 is used as a scratch register and
498 * a compiler temporary, but it's value is never used across
499 * a system call. Therefore %g6 is usable for orig_i0 storage.
500 */
501 if (pt_regs_is_syscall(regs) &&
502 (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
503 regs->u_regs[UREG_G6] = orig_i0;
504
505#ifdef CONFIG_COMPAT
506 if (test_thread_flag(TIF_32BIT)) {
507 do_signal32(regs);
508 return;
509 }
510#endif
511
512 has_handler = get_signal(&ksig);
513
514 restart_syscall = 0;
515 if (pt_regs_is_syscall(regs) &&
516 (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
517 restart_syscall = 1;
518 orig_i0 = regs->u_regs[UREG_G6];
519 }
520
521 if (has_handler) {
522 if (restart_syscall)
523 syscall_restart(orig_i0, regs, &ksig.ka.sa);
524 signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
525 } else {
526 if (restart_syscall) {
527 switch (regs->u_regs[UREG_I0]) {
528 case ERESTARTNOHAND:
529 case ERESTARTSYS:
530 case ERESTARTNOINTR:
531 /* replay the system call when we are done */
532 regs->u_regs[UREG_I0] = orig_i0;
533 regs->tpc -= 4;
534 regs->tnpc -= 4;
535 pt_regs_clear_syscall(regs);
536 /* fall through */
537 case ERESTART_RESTARTBLOCK:
538 regs->u_regs[UREG_G1] = __NR_restart_syscall;
539 regs->tpc -= 4;
540 regs->tnpc -= 4;
541 pt_regs_clear_syscall(regs);
542 }
543 }
544 restore_saved_sigmask();
545 }
546}
547
548void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
549{
550 user_exit();
551 if (thread_info_flags & _TIF_UPROBE)
552 uprobe_notify_resume(regs);
553 if (thread_info_flags & _TIF_SIGPENDING)
554 do_signal(regs, orig_i0);
555 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
556 clear_thread_flag(TIF_NOTIFY_RESUME);
557 tracehook_notify_resume(regs);
558 }
559 user_enter();
560}
561