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	if (!ptep)
332		goto out_irqs_on;
333	pte = *ptep;
334	if (!pte_present(pte))
335		goto out_unmap;
336
337	paddr = (unsigned long) page_address(pte_page(pte));
338
339	__asm__ __volatile__("flush	%0 + %1"
340			     : /* no outputs */
341			     : "r" (paddr),
342			       "r" (address & (PAGE_SIZE - 1))
343			     : "memory");
344
345out_unmap:
346	pte_unmap(ptep);
347out_irqs_on:
348	__asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
349
350}
351
352static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
353			 sigset_t *oldset)
354{
355	struct signal_frame32 __user *sf;
356	int i, err, wsaved;
357	void __user *tail;
358	int sigframe_size;
359	u32 psr;
360	compat_sigset_t seta;
361
362	/* 1. Make sure everything is clean */
363	synchronize_user_stack();
364	save_and_clear_fpu();
365
366	wsaved = get_thread_wsaved();
367
368	sigframe_size = sizeof(*sf);
369	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
370		sigframe_size += sizeof(__siginfo_fpu_t);
371	if (wsaved)
372		sigframe_size += sizeof(__siginfo_rwin_t);
373
374	sf = (struct signal_frame32 __user *)
375		get_sigframe(ksig, regs, sigframe_size);
376
377	if (invalid_frame_pointer(sf, sigframe_size)) {
378		if (show_unhandled_signals)
379			pr_info("%s[%d] bad frame in setup_frame32: %08lx TPC %08lx O7 %08lx\n",
380				current->comm, current->pid, (unsigned long)sf,
381				regs->tpc, regs->u_regs[UREG_I7]);
382		force_sigsegv(ksig->sig);
383		return -EINVAL;
384	}
385
386	tail = (sf + 1);
387
388	/* 2. Save the current process state */
389	if (test_thread_flag(TIF_32BIT)) {
390		regs->tpc &= 0xffffffff;
391		regs->tnpc &= 0xffffffff;
392	}
393	err  = put_user(regs->tpc, &sf->info.si_regs.pc);
394	err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
395	err |= __put_user(regs->y, &sf->info.si_regs.y);
396	psr = tstate_to_psr(regs->tstate);
397	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
398		psr |= PSR_EF;
399	err |= __put_user(psr, &sf->info.si_regs.psr);
400	for (i = 0; i < 16; i++)
401		err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
402	err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
403	err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
404	for (i = 1; i < 16; i++)
405		err |= __put_user(((u32 *)regs->u_regs)[2*i],
406				  &sf->v8plus.g_upper[i]);
407	err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
408			  &sf->v8plus.asi);
409
410	if (psr & PSR_EF) {
411		__siginfo_fpu_t __user *fp = tail;
412		tail += sizeof(*fp);
413		err |= save_fpu_state(regs, fp);
414		err |= __put_user((u64)fp, &sf->fpu_save);
415	} else {
416		err |= __put_user(0, &sf->fpu_save);
417	}
418	if (wsaved) {
419		__siginfo_rwin_t __user *rwp = tail;
420		tail += sizeof(*rwp);
421		err |= save_rwin_state(wsaved, rwp);
422		err |= __put_user((u64)rwp, &sf->rwin_save);
423		set_thread_wsaved(0);
424	} else {
425		err |= __put_user(0, &sf->rwin_save);
426	}
427
428	/* If these change we need to know - assignments to seta relies on these sizes */
429	BUILD_BUG_ON(_NSIG_WORDS != 1);
430	BUILD_BUG_ON(_COMPAT_NSIG_WORDS != 2);
431	seta.sig[1] = (oldset->sig[0] >> 32);
432	seta.sig[0] = oldset->sig[0];
433
434	err |= __put_user(seta.sig[0], &sf->info.si_mask);
435	err |= __copy_to_user(sf->extramask, &seta.sig[1],
436			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
437
438	if (!wsaved) {
439		err |= raw_copy_in_user((u32 __user *)sf,
440					(u32 __user *)(regs->u_regs[UREG_FP]),
441					sizeof(struct reg_window32));
442	} else {
443		struct reg_window *rp;
444
445		rp = &current_thread_info()->reg_window[wsaved - 1];
446		for (i = 0; i < 8; i++)
447			err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
448		for (i = 0; i < 6; i++)
449			err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
450		err |= __put_user(rp->ins[6], &sf->ss.fp);
451		err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
452	}
453	if (err)
454		return err;
455
456	/* 3. signal handler back-trampoline and parameters */
457	regs->u_regs[UREG_FP] = (unsigned long) sf;
458	regs->u_regs[UREG_I0] = ksig->sig;
459	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
460	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
461
462	/* 4. signal handler */
463	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
464	regs->tnpc = (regs->tpc + 4);
465	if (test_thread_flag(TIF_32BIT)) {
466		regs->tpc &= 0xffffffff;
467		regs->tnpc &= 0xffffffff;
468	}
469
470	/* 5. return to kernel instructions */
471	if (ksig->ka.ka_restorer) {
472		regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
473	} else {
474		unsigned long address = ((unsigned long)&(sf->insns[0]));
475
476		regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
477
478		err  = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
479		err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
480		if (err)
481			return err;
482		flush_signal_insns(address);
483	}
484	return 0;
485}
486
487static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
488			    sigset_t *oldset)
489{
490	struct rt_signal_frame32 __user *sf;
491	int i, err, wsaved;
492	void __user *tail;
493	int sigframe_size;
494	u32 psr;
495
496	/* 1. Make sure everything is clean */
497	synchronize_user_stack();
498	save_and_clear_fpu();
499
500	wsaved = get_thread_wsaved();
501
502	sigframe_size = sizeof(*sf);
503	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
504		sigframe_size += sizeof(__siginfo_fpu_t);
505	if (wsaved)
506		sigframe_size += sizeof(__siginfo_rwin_t);
507
508	sf = (struct rt_signal_frame32 __user *)
509		get_sigframe(ksig, regs, sigframe_size);
510
511	if (invalid_frame_pointer(sf, sigframe_size)) {
512		if (show_unhandled_signals)
513			pr_info("%s[%d] bad frame in setup_rt_frame32: %08lx TPC %08lx O7 %08lx\n",
514				current->comm, current->pid, (unsigned long)sf,
515				regs->tpc, regs->u_regs[UREG_I7]);
516		force_sigsegv(ksig->sig);
517		return -EINVAL;
518	}
519
520	tail = (sf + 1);
521
522	/* 2. Save the current process state */
523	if (test_thread_flag(TIF_32BIT)) {
524		regs->tpc &= 0xffffffff;
525		regs->tnpc &= 0xffffffff;
526	}
527	err  = put_user(regs->tpc, &sf->regs.pc);
528	err |= __put_user(regs->tnpc, &sf->regs.npc);
529	err |= __put_user(regs->y, &sf->regs.y);
530	psr = tstate_to_psr(regs->tstate);
531	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
532		psr |= PSR_EF;
533	err |= __put_user(psr, &sf->regs.psr);
534	for (i = 0; i < 16; i++)
535		err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
536	err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
537	err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
538	for (i = 1; i < 16; i++)
539		err |= __put_user(((u32 *)regs->u_regs)[2*i],
540				  &sf->v8plus.g_upper[i]);
541	err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
542			  &sf->v8plus.asi);
543
544	if (psr & PSR_EF) {
545		__siginfo_fpu_t __user *fp = tail;
546		tail += sizeof(*fp);
547		err |= save_fpu_state(regs, fp);
548		err |= __put_user((u64)fp, &sf->fpu_save);
549	} else {
550		err |= __put_user(0, &sf->fpu_save);
551	}
552	if (wsaved) {
553		__siginfo_rwin_t __user *rwp = tail;
554		tail += sizeof(*rwp);
555		err |= save_rwin_state(wsaved, rwp);
556		err |= __put_user((u64)rwp, &sf->rwin_save);
557		set_thread_wsaved(0);
558	} else {
559		err |= __put_user(0, &sf->rwin_save);
560	}
561
562	/* Update the siginfo structure.  */
563	err |= copy_siginfo_to_user32(&sf->info, &ksig->info);
564
565	/* Setup sigaltstack */
566	err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
567
568	err |= put_compat_sigset(&sf->mask, oldset, sizeof(compat_sigset_t));
569
570	if (!wsaved) {
571		err |= raw_copy_in_user((u32 __user *)sf,
572					(u32 __user *)(regs->u_regs[UREG_FP]),
573					sizeof(struct reg_window32));
574	} else {
575		struct reg_window *rp;
576
577		rp = &current_thread_info()->reg_window[wsaved - 1];
578		for (i = 0; i < 8; i++)
579			err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
580		for (i = 0; i < 6; i++)
581			err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
582		err |= __put_user(rp->ins[6], &sf->ss.fp);
583		err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
584	}
585	if (err)
586		return err;
587
588	/* 3. signal handler back-trampoline and parameters */
589	regs->u_regs[UREG_FP] = (unsigned long) sf;
590	regs->u_regs[UREG_I0] = ksig->sig;
591	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
592	regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
593
594	/* 4. signal handler */
595	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
596	regs->tnpc = (regs->tpc + 4);
597	if (test_thread_flag(TIF_32BIT)) {
598		regs->tpc &= 0xffffffff;
599		regs->tnpc &= 0xffffffff;
600	}
601
602	/* 5. return to kernel instructions */
603	if (ksig->ka.ka_restorer)
604		regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
605	else {
606		unsigned long address = ((unsigned long)&(sf->insns[0]));
607
608		regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
609
610		/* mov __NR_rt_sigreturn, %g1 */
611		err |= __put_user(0x82102065, &sf->insns[0]);
612
613		/* t 0x10 */
614		err |= __put_user(0x91d02010, &sf->insns[1]);
615		if (err)
616			return err;
617
618		flush_signal_insns(address);
619	}
620	return 0;
621}
622
623static inline void handle_signal32(struct ksignal *ksig,
624				  struct pt_regs *regs)
625{
626	sigset_t *oldset = sigmask_to_save();
627	int err;
628
629	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
630		err = setup_rt_frame32(ksig, regs, oldset);
631	else
632		err = setup_frame32(ksig, regs, oldset);
633
634	signal_setup_done(err, ksig, 0);
635}
636
637static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
638				     struct sigaction *sa)
639{
640	switch (regs->u_regs[UREG_I0]) {
641	case ERESTART_RESTARTBLOCK:
642	case ERESTARTNOHAND:
643	no_system_call_restart:
644		regs->u_regs[UREG_I0] = EINTR;
645		regs->tstate |= TSTATE_ICARRY;
646		break;
647	case ERESTARTSYS:
648		if (!(sa->sa_flags & SA_RESTART))
649			goto no_system_call_restart;
650		fallthrough;
651	case ERESTARTNOINTR:
652		regs->u_regs[UREG_I0] = orig_i0;
653		regs->tpc -= 4;
654		regs->tnpc -= 4;
655	}
656}
657
658/* Note that 'init' is a special process: it doesn't get signals it doesn't
659 * want to handle. Thus you cannot kill init even with a SIGKILL even by
660 * mistake.
661 */
662void do_signal32(struct pt_regs * regs)
663{
664	struct ksignal ksig;
665	unsigned long orig_i0 = 0;
666	int restart_syscall = 0;
667	bool has_handler = get_signal(&ksig);
668
669	if (pt_regs_is_syscall(regs) &&
670	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
671		restart_syscall = 1;
672		orig_i0 = regs->u_regs[UREG_G6];
673	}
674
675	if (has_handler) {
676		if (restart_syscall)
677			syscall_restart32(orig_i0, regs, &ksig.ka.sa);
678		handle_signal32(&ksig, regs);
679	} else {
680		if (restart_syscall) {
681			switch (regs->u_regs[UREG_I0]) {
682			case ERESTARTNOHAND:
683	     		case ERESTARTSYS:
684			case ERESTARTNOINTR:
685				/* replay the system call when we are done */
686				regs->u_regs[UREG_I0] = orig_i0;
687				regs->tpc -= 4;
688				regs->tnpc -= 4;
689				pt_regs_clear_syscall(regs);
690				fallthrough;
691			case ERESTART_RESTARTBLOCK:
692				regs->u_regs[UREG_G1] = __NR_restart_syscall;
693				regs->tpc -= 4;
694				regs->tnpc -= 4;
695				pt_regs_clear_syscall(regs);
696			}
697		}
698		restore_saved_sigmask();
699	}
700}
701
702struct sigstack32 {
703	u32 the_stack;
704	int cur_status;
705};
706
707asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
708{
709	struct sigstack32 __user *ssptr =
710		(struct sigstack32 __user *)((unsigned long)(u_ssptr));
711	struct sigstack32 __user *ossptr =
712		(struct sigstack32 __user *)((unsigned long)(u_ossptr));
713	int ret = -EFAULT;
714
715	/* First see if old state is wanted. */
716	if (ossptr) {
717		if (put_user(current->sas_ss_sp + current->sas_ss_size,
718			     &ossptr->the_stack) ||
719		    __put_user(on_sig_stack(sp), &ossptr->cur_status))
720			goto out;
721	}
722
723	/* Now see if we want to update the new state. */
724	if (ssptr) {
725		u32 ss_sp;
726
727		if (get_user(ss_sp, &ssptr->the_stack))
728			goto out;
729
730		/* If the current stack was set with sigaltstack, don't
731		 * swap stacks while we are on it.
732		 */
733		ret = -EPERM;
734		if (current->sas_ss_sp && on_sig_stack(sp))
735			goto out;
736
737		/* Since we don't know the extent of the stack, and we don't
738		 * track onstack-ness, but rather calculate it, we must
739		 * presume a size.  Ho hum this interface is lossy.
740		 */
741		current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
742		current->sas_ss_size = SIGSTKSZ;
743	}
744
745	ret = 0;
746out:
747	return ret;
748}
749
750/*
751 * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
752 * changes likely come with new fields that should be added below.
753 */
754static_assert(NSIGILL	== 11);
755static_assert(NSIGFPE	== 15);
756static_assert(NSIGSEGV	== 10);
757static_assert(NSIGBUS	== 5);
758static_assert(NSIGTRAP	== 6);
759static_assert(NSIGCHLD	== 6);
760static_assert(NSIGSYS	== 2);
761static_assert(sizeof(compat_siginfo_t) == 128);
762static_assert(__alignof__(compat_siginfo_t) == 4);
763static_assert(offsetof(compat_siginfo_t, si_signo)	== 0x00);
764static_assert(offsetof(compat_siginfo_t, si_errno)	== 0x04);
765static_assert(offsetof(compat_siginfo_t, si_code)	== 0x08);
766static_assert(offsetof(compat_siginfo_t, si_pid)	== 0x0c);
767static_assert(offsetof(compat_siginfo_t, si_uid)	== 0x10);
768static_assert(offsetof(compat_siginfo_t, si_tid)	== 0x0c);
769static_assert(offsetof(compat_siginfo_t, si_overrun)	== 0x10);
770static_assert(offsetof(compat_siginfo_t, si_status)	== 0x14);
771static_assert(offsetof(compat_siginfo_t, si_utime)	== 0x18);
772static_assert(offsetof(compat_siginfo_t, si_stime)	== 0x1c);
773static_assert(offsetof(compat_siginfo_t, si_value)	== 0x14);
774static_assert(offsetof(compat_siginfo_t, si_int)	== 0x14);
775static_assert(offsetof(compat_siginfo_t, si_ptr)	== 0x14);
776static_assert(offsetof(compat_siginfo_t, si_addr)	== 0x0c);
777static_assert(offsetof(compat_siginfo_t, si_trapno)	== 0x10);
778static_assert(offsetof(compat_siginfo_t, si_addr_lsb)	== 0x10);
779static_assert(offsetof(compat_siginfo_t, si_lower)	== 0x14);
780static_assert(offsetof(compat_siginfo_t, si_upper)	== 0x18);
781static_assert(offsetof(compat_siginfo_t, si_pkey)	== 0x14);
782static_assert(offsetof(compat_siginfo_t, si_perf_data)	== 0x10);
783static_assert(offsetof(compat_siginfo_t, si_perf_type)	== 0x14);
784static_assert(offsetof(compat_siginfo_t, si_perf_flags)	== 0x18);
785static_assert(offsetof(compat_siginfo_t, si_band)	== 0x0c);
786static_assert(offsetof(compat_siginfo_t, si_fd)		== 0x10);
787