1// SPDX-License-Identifier: GPL-2.0
  2/*  arch/sparc64/kernel/signal32.c
  3 *
  4 *  Copyright (C) 1991, 1992  Linus Torvalds
  5 *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
  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#include <linux/sched.h>
 12#include <linux/kernel.h>
 13#include <linux/signal.h>
 14#include <linux/errno.h>
 15#include <linux/wait.h>
 16#include <linux/ptrace.h>
 17#include <linux/unistd.h>
 18#include <linux/mm.h>
 19#include <linux/tty.h>
 20#include <linux/binfmts.h>
 21#include <linux/compat.h>
 22#include <linux/bitops.h>
 23
 24#include <linux/uaccess.h>
 25#include <asm/ptrace.h>
 26#include <asm/psrcompat.h>
 27#include <asm/fpumacro.h>
 28#include <asm/visasm.h>
 29#include <asm/compat_signal.h>
 30#include <asm/switch_to.h>
 31
 32#include "sigutil.h"
 33#include "kernel.h"
 34
 35/* This magic should be in g_upper[0] for all upper parts
 36 * to be valid.
 37 */
 38#define SIGINFO_EXTRA_V8PLUS_MAGIC	0x130e269
 39typedef struct {
 40	unsigned int g_upper[8];
 41	unsigned int o_upper[8];
 42	unsigned int asi;
 43} siginfo_extra_v8plus_t;
 44
 45struct signal_frame32 {
 46	struct sparc_stackf32	ss;
 47	__siginfo32_t		info;
 48	/* __siginfo_fpu_t * */ u32 fpu_save;
 49	unsigned int		insns[2];
 50	unsigned int		extramask[_COMPAT_NSIG_WORDS - 1];
 51	unsigned int		extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
 52	/* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
 53	siginfo_extra_v8plus_t	v8plus;
 54	/* __siginfo_rwin_t * */u32 rwin_save;
 55} __attribute__((aligned(8)));
 56
 57struct rt_signal_frame32 {
 58	struct sparc_stackf32	ss;
 59	compat_siginfo_t	info;
 60	struct pt_regs32	regs;
 61	compat_sigset_t		mask;
 62	/* __siginfo_fpu_t * */ u32 fpu_save;
 63	unsigned int		insns[2];
 64	compat_stack_t		stack;
 65	unsigned int		extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
 66	/* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
 67	siginfo_extra_v8plus_t	v8plus;
 68	/* __siginfo_rwin_t * */u32 rwin_save;
 69} __attribute__((aligned(8)));
 70
 71/* Checks if the fp is valid.  We always build signal frames which are
 72 * 16-byte aligned, therefore we can always enforce that the restore
 73 * frame has that property as well.
 74 */
 75static bool invalid_frame_pointer(void __user *fp, int fplen)
 76{
 77	if ((((unsigned long) fp) & 15) ||
 78	    ((unsigned long)fp) > 0x100000000ULL - fplen)
 79		return true;
 80	return false;
 81}
 82
 83void do_sigreturn32(struct pt_regs *regs)
 84{
 85	struct signal_frame32 __user *sf;
 86	compat_uptr_t fpu_save;
 87	compat_uptr_t rwin_save;
 88	unsigned int psr, ufp;
 89	unsigned int pc, npc;
 90	sigset_t set;
 91	compat_sigset_t seta;
 92	int err, i;
 93	
 94	/* Always make any pending restarted system calls return -EINTR */
 95	current->restart_block.fn = do_no_restart_syscall;
 96
 97	synchronize_user_stack();
 98
 99	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
100	sf = (struct signal_frame32 __user *) regs->u_regs[UREG_FP];
101
102	/* 1. Make sure we are not getting garbage from the user */
103	if (invalid_frame_pointer(sf, sizeof(*sf)))
104		goto segv;
105
106	if (get_user(ufp, &sf->info.si_regs.u_regs[UREG_FP]))
107		goto segv;
108
109	if (ufp & 0x7)
110		goto segv;
111
112	if (__get_user(pc, &sf->info.si_regs.pc) ||
113	    __get_user(npc, &sf->info.si_regs.npc))
114		goto segv;
115
116	if ((pc | npc) & 3)
117		goto segv;
118
119	if (test_thread_flag(TIF_32BIT)) {
120		pc &= 0xffffffff;
121		npc &= 0xffffffff;
122	}
123	regs->tpc = pc;
124	regs->tnpc = npc;
125
126	/* 2. Restore the state */
127	err = __get_user(regs->y, &sf->info.si_regs.y);
128	err |= __get_user(psr, &sf->info.si_regs.psr);
129
130	for (i = UREG_G1; i <= UREG_I7; i++)
131		err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
132	if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
133		err |= __get_user(i, &sf->v8plus.g_upper[0]);
134		if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
135			unsigned long asi;
136
137			for (i = UREG_G1; i <= UREG_I7; i++)
138				err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
139			err |= __get_user(asi, &sf->v8plus.asi);
140			regs->tstate &= ~TSTATE_ASI;
141			regs->tstate |= ((asi & 0xffUL) << 24UL);
142		}
143	}
144
145	/* User can only change condition codes in %tstate. */
146	regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
147	regs->tstate |= psr_to_tstate_icc(psr);
148
149	/* Prevent syscall restart.  */
150	pt_regs_clear_syscall(regs);
151
152	err |= __get_user(fpu_save, &sf->fpu_save);
153	if (!err && fpu_save)
154		err |= restore_fpu_state(regs, compat_ptr(fpu_save));
155	err |= __get_user(rwin_save, &sf->rwin_save);
156	if (!err && rwin_save) {
157		if (restore_rwin_state(compat_ptr(rwin_save)))
158			goto segv;
159	}
160	err |= __get_user(seta.sig[0], &sf->info.si_mask);
161	err |= copy_from_user(&seta.sig[1], &sf->extramask,
162			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
163	if (err)
164	    	goto segv;
165
166	set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
167	set_current_blocked(&set);
168	return;
169
170segv:
171	force_sig(SIGSEGV);
172}
173
174asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
175{
176	struct rt_signal_frame32 __user *sf;
177	unsigned int psr, pc, npc, ufp;
178	compat_uptr_t fpu_save;
179	compat_uptr_t rwin_save;
180	sigset_t set;
181	int err, i;
182	
183	/* Always make any pending restarted system calls return -EINTR */
184	current->restart_block.fn = do_no_restart_syscall;
185
186	synchronize_user_stack();
187	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
188	sf = (struct rt_signal_frame32 __user *) regs->u_regs[UREG_FP];
189
190	/* 1. Make sure we are not getting garbage from the user */
191	if (invalid_frame_pointer(sf, sizeof(*sf)))
192		goto segv;
193
194	if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
195		goto segv;
196
197	if (ufp & 0x7)
198		goto segv;
199
200	if (__get_user(pc, &sf->regs.pc) || 
201	    __get_user(npc, &sf->regs.npc))
202		goto segv;
203
204	if ((pc | npc) & 3)
205		goto segv;
206
207	if (test_thread_flag(TIF_32BIT)) {
208		pc &= 0xffffffff;
209		npc &= 0xffffffff;
210	}
211	regs->tpc = pc;
212	regs->tnpc = npc;
213
214	/* 2. Restore the state */
215	err = __get_user(regs->y, &sf->regs.y);
216	err |= __get_user(psr, &sf->regs.psr);
217	
218	for (i = UREG_G1; i <= UREG_I7; i++)
219		err |= __get_user(regs->u_regs[i], &sf->regs.u_regs[i]);
220	if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
221		err |= __get_user(i, &sf->v8plus.g_upper[0]);
222		if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
223			unsigned long asi;
224
225			for (i = UREG_G1; i <= UREG_I7; i++)
226				err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
227			err |= __get_user(asi, &sf->v8plus.asi);
228			regs->tstate &= ~TSTATE_ASI;
229			regs->tstate |= ((asi & 0xffUL) << 24UL);
230		}
231	}
232
233	/* User can only change condition codes in %tstate. */
234	regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
235	regs->tstate |= psr_to_tstate_icc(psr);
236
237	/* Prevent syscall restart.  */
238	pt_regs_clear_syscall(regs);
239
240	err |= __get_user(fpu_save, &sf->fpu_save);
241	if (!err && fpu_save)
242		err |= restore_fpu_state(regs, compat_ptr(fpu_save));
243	err |= get_compat_sigset(&set, &sf->mask);
244	err |= compat_restore_altstack(&sf->stack);
245	if (err)
246		goto segv;
247		
248	err |= __get_user(rwin_save, &sf->rwin_save);
249	if (!err && rwin_save) {
250		if (restore_rwin_state(compat_ptr(rwin_save)))
251			goto segv;
252	}
253
254	set_current_blocked(&set);
255	return;
256segv:
257	force_sig(SIGSEGV);
258}
259
260static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
261{
262	unsigned long sp;
263	
264	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
265	sp = regs->u_regs[UREG_FP];
266	
267	/*
268	 * If we are on the alternate signal stack and would overflow it, don't.
269	 * Return an always-bogus address instead so we will die with SIGSEGV.
270	 */
271	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
272		return (void __user *) -1L;
273
274	/* This is the X/Open sanctioned signal stack switching.  */
275	sp = sigsp(sp, ksig) - framesize;
276
277	/* Always align the stack frame.  This handles two cases.  First,
278	 * sigaltstack need not be mindful of platform specific stack
279	 * alignment.  Second, if we took this signal because the stack
280	 * is not aligned properly, we'd like to take the signal cleanly
281	 * and report that.
282	 */
283	sp &= ~15UL;
284
285	return (void __user *) sp;
286}
287
288/* The I-cache flush instruction only works in the primary ASI, which
289 * right now is the nucleus, aka. kernel space.
290 *
291 * Therefore we have to kick the instructions out using the kernel
292 * side linear mapping of the physical address backing the user
293 * instructions.
294 */
295static void flush_signal_insns(unsigned long address)
296{
297	unsigned long pstate, paddr;
298	pte_t *ptep, pte;
299	pgd_t *pgdp;
300	p4d_t *p4dp;
301	pud_t *pudp;
302	pmd_t *pmdp;
303
304	/* Commit all stores of the instructions we are about to flush.  */
305	wmb();
306
307	/* Disable cross-call reception.  In this way even a very wide
308	 * munmap() on another cpu can't tear down the page table
309	 * hierarchy from underneath us, since that can't complete
310	 * until the IPI tlb flush returns.
311	 */
312
313	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
314	__asm__ __volatile__("wrpr %0, %1, %%pstate"
315				: : "r" (pstate), "i" (PSTATE_IE));
316
317	pgdp = pgd_offset(current->mm, address);
318	if (pgd_none(*pgdp))
319		goto out_irqs_on;
320	p4dp = p4d_offset(pgdp, address);
321	if (p4d_none(*p4dp))
322		goto out_irqs_on;
323	pudp = pud_offset(p4dp, address);
324	if (pud_none(*pudp))
325		goto out_irqs_on;
326	pmdp = pmd_offset(pudp, address);
327	if (pmd_none(*pmdp))
328		goto out_irqs_on;
329
330	ptep = pte_offset_map(pmdp, address);
 
 
331	pte = *ptep;
332	if (!pte_present(pte))
333		goto out_unmap;
334
335	paddr = (unsigned long) page_address(pte_page(pte));
336
337	__asm__ __volatile__("flush	%0 + %1"
338			     : /* no outputs */
339			     : "r" (paddr),
340			       "r" (address & (PAGE_SIZE - 1))
341			     : "memory");
342
343out_unmap:
344	pte_unmap(ptep);
345out_irqs_on:
346	__asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
347
348}
349
350static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
351			 sigset_t *oldset)
352{
353	struct signal_frame32 __user *sf;
354	int i, err, wsaved;
355	void __user *tail;
356	int sigframe_size;
357	u32 psr;
358	compat_sigset_t seta;
359
360	/* 1. Make sure everything is clean */
361	synchronize_user_stack();
362	save_and_clear_fpu();
363	
364	wsaved = get_thread_wsaved();
365
366	sigframe_size = sizeof(*sf);
367	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
368		sigframe_size += sizeof(__siginfo_fpu_t);
369	if (wsaved)
370		sigframe_size += sizeof(__siginfo_rwin_t);
371
372	sf = (struct signal_frame32 __user *)
373		get_sigframe(ksig, regs, sigframe_size);
374	
375	if (invalid_frame_pointer(sf, sigframe_size)) {
376		if (show_unhandled_signals)
377			pr_info("%s[%d] bad frame in setup_frame32: %08lx TPC %08lx O7 %08lx\n",
378				current->comm, current->pid, (unsigned long)sf,
379				regs->tpc, regs->u_regs[UREG_I7]);
380		force_sigsegv(ksig->sig);
381		return -EINVAL;
382	}
383
384	tail = (sf + 1);
385
386	/* 2. Save the current process state */
387	if (test_thread_flag(TIF_32BIT)) {
388		regs->tpc &= 0xffffffff;
389		regs->tnpc &= 0xffffffff;
390	}
391	err  = put_user(regs->tpc, &sf->info.si_regs.pc);
392	err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
393	err |= __put_user(regs->y, &sf->info.si_regs.y);
394	psr = tstate_to_psr(regs->tstate);
395	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
396		psr |= PSR_EF;
397	err |= __put_user(psr, &sf->info.si_regs.psr);
398	for (i = 0; i < 16; i++)
399		err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
400	err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
401	err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
402	for (i = 1; i < 16; i++)
403		err |= __put_user(((u32 *)regs->u_regs)[2*i],
404				  &sf->v8plus.g_upper[i]);
405	err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
406			  &sf->v8plus.asi);
407
408	if (psr & PSR_EF) {
409		__siginfo_fpu_t __user *fp = tail;
410		tail += sizeof(*fp);
411		err |= save_fpu_state(regs, fp);
412		err |= __put_user((u64)fp, &sf->fpu_save);
413	} else {
414		err |= __put_user(0, &sf->fpu_save);
415	}
416	if (wsaved) {
417		__siginfo_rwin_t __user *rwp = tail;
418		tail += sizeof(*rwp);
419		err |= save_rwin_state(wsaved, rwp);
420		err |= __put_user((u64)rwp, &sf->rwin_save);
421		set_thread_wsaved(0);
422	} else {
423		err |= __put_user(0, &sf->rwin_save);
424	}
425
426	/* If these change we need to know - assignments to seta relies on these sizes */
427	BUILD_BUG_ON(_NSIG_WORDS != 1);
428	BUILD_BUG_ON(_COMPAT_NSIG_WORDS != 2);
429	seta.sig[1] = (oldset->sig[0] >> 32);
430	seta.sig[0] = oldset->sig[0];
431
432	err |= __put_user(seta.sig[0], &sf->info.si_mask);
433	err |= __copy_to_user(sf->extramask, &seta.sig[1],
434			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
435
436	if (!wsaved) {
437		err |= raw_copy_in_user((u32 __user *)sf,
438					(u32 __user *)(regs->u_regs[UREG_FP]),
439					sizeof(struct reg_window32));
440	} else {
441		struct reg_window *rp;
442
443		rp = &current_thread_info()->reg_window[wsaved - 1];
444		for (i = 0; i < 8; i++)
445			err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
446		for (i = 0; i < 6; i++)
447			err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
448		err |= __put_user(rp->ins[6], &sf->ss.fp);
449		err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
450	}	
451	if (err)
452		return err;
453
454	/* 3. signal handler back-trampoline and parameters */
455	regs->u_regs[UREG_FP] = (unsigned long) sf;
456	regs->u_regs[UREG_I0] = ksig->sig;
457	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
458	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
459
460	/* 4. signal handler */
461	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
462	regs->tnpc = (regs->tpc + 4);
463	if (test_thread_flag(TIF_32BIT)) {
464		regs->tpc &= 0xffffffff;
465		regs->tnpc &= 0xffffffff;
466	}
467
468	/* 5. return to kernel instructions */
469	if (ksig->ka.ka_restorer) {
470		regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
471	} else {
472		unsigned long address = ((unsigned long)&(sf->insns[0]));
473
474		regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
475	
476		err  = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
477		err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
478		if (err)
479			return err;
480		flush_signal_insns(address);
481	}
482	return 0;
483}
484
485static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
486			    sigset_t *oldset)
487{
488	struct rt_signal_frame32 __user *sf;
489	int i, err, wsaved;
490	void __user *tail;
491	int sigframe_size;
492	u32 psr;
493
494	/* 1. Make sure everything is clean */
495	synchronize_user_stack();
496	save_and_clear_fpu();
497	
498	wsaved = get_thread_wsaved();
499
500	sigframe_size = sizeof(*sf);
501	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
502		sigframe_size += sizeof(__siginfo_fpu_t);
503	if (wsaved)
504		sigframe_size += sizeof(__siginfo_rwin_t);
505
506	sf = (struct rt_signal_frame32 __user *)
507		get_sigframe(ksig, regs, sigframe_size);
508	
509	if (invalid_frame_pointer(sf, sigframe_size)) {
510		if (show_unhandled_signals)
511			pr_info("%s[%d] bad frame in setup_rt_frame32: %08lx TPC %08lx O7 %08lx\n",
512				current->comm, current->pid, (unsigned long)sf,
513				regs->tpc, regs->u_regs[UREG_I7]);
514		force_sigsegv(ksig->sig);
515		return -EINVAL;
516	}
517
518	tail = (sf + 1);
519
520	/* 2. Save the current process state */
521	if (test_thread_flag(TIF_32BIT)) {
522		regs->tpc &= 0xffffffff;
523		regs->tnpc &= 0xffffffff;
524	}
525	err  = put_user(regs->tpc, &sf->regs.pc);
526	err |= __put_user(regs->tnpc, &sf->regs.npc);
527	err |= __put_user(regs->y, &sf->regs.y);
528	psr = tstate_to_psr(regs->tstate);
529	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
530		psr |= PSR_EF;
531	err |= __put_user(psr, &sf->regs.psr);
532	for (i = 0; i < 16; i++)
533		err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
534	err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
535	err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
536	for (i = 1; i < 16; i++)
537		err |= __put_user(((u32 *)regs->u_regs)[2*i],
538				  &sf->v8plus.g_upper[i]);
539	err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
540			  &sf->v8plus.asi);
541
542	if (psr & PSR_EF) {
543		__siginfo_fpu_t __user *fp = tail;
544		tail += sizeof(*fp);
545		err |= save_fpu_state(regs, fp);
546		err |= __put_user((u64)fp, &sf->fpu_save);
547	} else {
548		err |= __put_user(0, &sf->fpu_save);
549	}
550	if (wsaved) {
551		__siginfo_rwin_t __user *rwp = tail;
552		tail += sizeof(*rwp);
553		err |= save_rwin_state(wsaved, rwp);
554		err |= __put_user((u64)rwp, &sf->rwin_save);
555		set_thread_wsaved(0);
556	} else {
557		err |= __put_user(0, &sf->rwin_save);
558	}
559
560	/* Update the siginfo structure.  */
561	err |= copy_siginfo_to_user32(&sf->info, &ksig->info);
562	
563	/* Setup sigaltstack */
564	err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
565
566	err |= put_compat_sigset(&sf->mask, oldset, sizeof(compat_sigset_t));
567
568	if (!wsaved) {
569		err |= raw_copy_in_user((u32 __user *)sf,
570					(u32 __user *)(regs->u_regs[UREG_FP]),
571					sizeof(struct reg_window32));
572	} else {
573		struct reg_window *rp;
574
575		rp = &current_thread_info()->reg_window[wsaved - 1];
576		for (i = 0; i < 8; i++)
577			err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
578		for (i = 0; i < 6; i++)
579			err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
580		err |= __put_user(rp->ins[6], &sf->ss.fp);
581		err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
582	}
583	if (err)
584		return err;
585	
586	/* 3. signal handler back-trampoline and parameters */
587	regs->u_regs[UREG_FP] = (unsigned long) sf;
588	regs->u_regs[UREG_I0] = ksig->sig;
589	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
590	regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
591
592	/* 4. signal handler */
593	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
594	regs->tnpc = (regs->tpc + 4);
595	if (test_thread_flag(TIF_32BIT)) {
596		regs->tpc &= 0xffffffff;
597		regs->tnpc &= 0xffffffff;
598	}
599
600	/* 5. return to kernel instructions */
601	if (ksig->ka.ka_restorer)
602		regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
603	else {
604		unsigned long address = ((unsigned long)&(sf->insns[0]));
605
606		regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
607	
608		/* mov __NR_rt_sigreturn, %g1 */
609		err |= __put_user(0x82102065, &sf->insns[0]);
610
611		/* t 0x10 */
612		err |= __put_user(0x91d02010, &sf->insns[1]);
613		if (err)
614			return err;
615
616		flush_signal_insns(address);
617	}
618	return 0;
619}
620
621static inline void handle_signal32(struct ksignal *ksig, 
622				  struct pt_regs *regs)
623{
624	sigset_t *oldset = sigmask_to_save();
625	int err;
626
627	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
628		err = setup_rt_frame32(ksig, regs, oldset);
629	else
630		err = setup_frame32(ksig, regs, oldset);
631
632	signal_setup_done(err, ksig, 0);
633}
634
635static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
636				     struct sigaction *sa)
637{
638	switch (regs->u_regs[UREG_I0]) {
639	case ERESTART_RESTARTBLOCK:
640	case ERESTARTNOHAND:
641	no_system_call_restart:
642		regs->u_regs[UREG_I0] = EINTR;
643		regs->tstate |= TSTATE_ICARRY;
644		break;
645	case ERESTARTSYS:
646		if (!(sa->sa_flags & SA_RESTART))
647			goto no_system_call_restart;
648		fallthrough;
649	case ERESTARTNOINTR:
650		regs->u_regs[UREG_I0] = orig_i0;
651		regs->tpc -= 4;
652		regs->tnpc -= 4;
653	}
654}
655
656/* Note that 'init' is a special process: it doesn't get signals it doesn't
657 * want to handle. Thus you cannot kill init even with a SIGKILL even by
658 * mistake.
659 */
660void do_signal32(struct pt_regs * regs)
661{
662	struct ksignal ksig;
663	unsigned long orig_i0 = 0;
664	int restart_syscall = 0;
665	bool has_handler = get_signal(&ksig);
666
667	if (pt_regs_is_syscall(regs) &&
668	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
669		restart_syscall = 1;
670		orig_i0 = regs->u_regs[UREG_G6];
671	}
672
673	if (has_handler) {
674		if (restart_syscall)
675			syscall_restart32(orig_i0, regs, &ksig.ka.sa);
676		handle_signal32(&ksig, regs);
677	} else {
678		if (restart_syscall) {
679			switch (regs->u_regs[UREG_I0]) {
680			case ERESTARTNOHAND:
681	     		case ERESTARTSYS:
682			case ERESTARTNOINTR:
683				/* replay the system call when we are done */
684				regs->u_regs[UREG_I0] = orig_i0;
685				regs->tpc -= 4;
686				regs->tnpc -= 4;
687				pt_regs_clear_syscall(regs);
688				fallthrough;
689			case ERESTART_RESTARTBLOCK:
690				regs->u_regs[UREG_G1] = __NR_restart_syscall;
691				regs->tpc -= 4;
692				regs->tnpc -= 4;
693				pt_regs_clear_syscall(regs);
694			}
695		}
696		restore_saved_sigmask();
697	}
698}
699
700struct sigstack32 {
701	u32 the_stack;
702	int cur_status;
703};
704
705asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
706{
707	struct sigstack32 __user *ssptr =
708		(struct sigstack32 __user *)((unsigned long)(u_ssptr));
709	struct sigstack32 __user *ossptr =
710		(struct sigstack32 __user *)((unsigned long)(u_ossptr));
711	int ret = -EFAULT;
712
713	/* First see if old state is wanted. */
714	if (ossptr) {
715		if (put_user(current->sas_ss_sp + current->sas_ss_size,
716			     &ossptr->the_stack) ||
717		    __put_user(on_sig_stack(sp), &ossptr->cur_status))
718			goto out;
719	}
720	
721	/* Now see if we want to update the new state. */
722	if (ssptr) {
723		u32 ss_sp;
724
725		if (get_user(ss_sp, &ssptr->the_stack))
726			goto out;
727
728		/* If the current stack was set with sigaltstack, don't
729		 * swap stacks while we are on it.
730		 */
731		ret = -EPERM;
732		if (current->sas_ss_sp && on_sig_stack(sp))
733			goto out;
734			
735		/* Since we don't know the extent of the stack, and we don't
736		 * track onstack-ness, but rather calculate it, we must
737		 * presume a size.  Ho hum this interface is lossy.
738		 */
739		current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
740		current->sas_ss_size = SIGSTKSZ;
741	}
742	
743	ret = 0;
744out:
745	return ret;
746}
747
748/*
749 * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
750 * changes likely come with new fields that should be added below.
751 */
752static_assert(NSIGILL	== 11);
753static_assert(NSIGFPE	== 15);
754static_assert(NSIGSEGV	== 9);
755static_assert(NSIGBUS	== 5);
756static_assert(NSIGTRAP	== 6);
757static_assert(NSIGCHLD	== 6);
758static_assert(NSIGSYS	== 2);
759static_assert(sizeof(compat_siginfo_t) == 128);
760static_assert(__alignof__(compat_siginfo_t) == 4);
761static_assert(offsetof(compat_siginfo_t, si_signo)	== 0x00);
762static_assert(offsetof(compat_siginfo_t, si_errno)	== 0x04);
763static_assert(offsetof(compat_siginfo_t, si_code)	== 0x08);
764static_assert(offsetof(compat_siginfo_t, si_pid)	== 0x0c);
765static_assert(offsetof(compat_siginfo_t, si_uid)	== 0x10);
766static_assert(offsetof(compat_siginfo_t, si_tid)	== 0x0c);
767static_assert(offsetof(compat_siginfo_t, si_overrun)	== 0x10);
768static_assert(offsetof(compat_siginfo_t, si_status)	== 0x14);
769static_assert(offsetof(compat_siginfo_t, si_utime)	== 0x18);
770static_assert(offsetof(compat_siginfo_t, si_stime)	== 0x1c);
771static_assert(offsetof(compat_siginfo_t, si_value)	== 0x14);
772static_assert(offsetof(compat_siginfo_t, si_int)	== 0x14);
773static_assert(offsetof(compat_siginfo_t, si_ptr)	== 0x14);
774static_assert(offsetof(compat_siginfo_t, si_addr)	== 0x0c);
775static_assert(offsetof(compat_siginfo_t, si_trapno)	== 0x10);
776static_assert(offsetof(compat_siginfo_t, si_addr_lsb)	== 0x10);
777static_assert(offsetof(compat_siginfo_t, si_lower)	== 0x14);
778static_assert(offsetof(compat_siginfo_t, si_upper)	== 0x18);
779static_assert(offsetof(compat_siginfo_t, si_pkey)	== 0x14);
780static_assert(offsetof(compat_siginfo_t, si_perf_data)	== 0x10);
781static_assert(offsetof(compat_siginfo_t, si_perf_type)	== 0x14);
782static_assert(offsetof(compat_siginfo_t, si_perf_flags)	== 0x18);
783static_assert(offsetof(compat_siginfo_t, si_band)	== 0x0c);
784static_assert(offsetof(compat_siginfo_t, si_fd)		== 0x10);