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