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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
4 *
5 * PowerPC version
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7 * Copyright (C) 2001 IBM
8 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
10 *
11 * Derived from "arch/i386/kernel/signal.c"
12 * Copyright (C) 1991, 1992 Linus Torvalds
13 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
14 */
15
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/smp.h>
19#include <linux/kernel.h>
20#include <linux/signal.h>
21#include <linux/errno.h>
22#include <linux/elf.h>
23#include <linux/ptrace.h>
24#include <linux/pagemap.h>
25#include <linux/ratelimit.h>
26#include <linux/syscalls.h>
27#ifdef CONFIG_PPC64
28#include <linux/compat.h>
29#else
30#include <linux/wait.h>
31#include <linux/unistd.h>
32#include <linux/stddef.h>
33#include <linux/tty.h>
34#include <linux/binfmts.h>
35#endif
36
37#include <linux/uaccess.h>
38#include <asm/cacheflush.h>
39#include <asm/syscalls.h>
40#include <asm/sigcontext.h>
41#include <asm/vdso.h>
42#include <asm/switch_to.h>
43#include <asm/tm.h>
44#include <asm/asm-prototypes.h>
45#ifdef CONFIG_PPC64
46#include "ppc32.h"
47#include <asm/unistd.h>
48#else
49#include <asm/ucontext.h>
50#endif
51
52#include "signal.h"
53
54
55#ifdef CONFIG_PPC64
56#define old_sigaction old_sigaction32
57#define sigcontext sigcontext32
58#define mcontext mcontext32
59#define ucontext ucontext32
60
61/*
62 * Userspace code may pass a ucontext which doesn't include VSX added
63 * at the end. We need to check for this case.
64 */
65#define UCONTEXTSIZEWITHOUTVSX \
66 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
67
68/*
69 * Returning 0 means we return to userspace via
70 * ret_from_except and thus restore all user
71 * registers from *regs. This is what we need
72 * to do when a signal has been delivered.
73 */
74
75#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
76#undef __SIGNAL_FRAMESIZE
77#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
78#undef ELF_NVRREG
79#define ELF_NVRREG ELF_NVRREG32
80
81/*
82 * Functions for flipping sigsets (thanks to brain dead generic
83 * implementation that makes things simple for little endian only)
84 */
85#define unsafe_put_sigset_t unsafe_put_compat_sigset
86#define unsafe_get_sigset_t unsafe_get_compat_sigset
87
88#define to_user_ptr(p) ptr_to_compat(p)
89#define from_user_ptr(p) compat_ptr(p)
90
91static __always_inline int
92__unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
93{
94 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
95 int val, i;
96
97 for (i = 0; i <= PT_RESULT; i ++) {
98 /* Force usr to alway see softe as 1 (interrupts enabled) */
99 if (i == PT_SOFTE)
100 val = 1;
101 else
102 val = gregs[i];
103
104 unsafe_put_user(val, &frame->mc_gregs[i], failed);
105 }
106 return 0;
107
108failed:
109 return 1;
110}
111
112static __always_inline int
113__unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr)
114{
115 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
116 int i;
117
118 for (i = 0; i <= PT_RESULT; i++) {
119 if ((i == PT_MSR) || (i == PT_SOFTE))
120 continue;
121 unsafe_get_user(gregs[i], &sr->mc_gregs[i], failed);
122 }
123 return 0;
124
125failed:
126 return 1;
127}
128
129#else /* CONFIG_PPC64 */
130
131#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
132
133#define unsafe_put_sigset_t(uset, set, label) do { \
134 sigset_t __user *__us = uset ; \
135 const sigset_t *__s = set; \
136 \
137 unsafe_copy_to_user(__us, __s, sizeof(*__us), label); \
138} while (0)
139
140#define unsafe_get_sigset_t unsafe_get_user_sigset
141
142#define to_user_ptr(p) ((unsigned long)(p))
143#define from_user_ptr(p) ((void __user *)(p))
144
145static __always_inline int
146__unsafe_save_general_regs(struct pt_regs *regs, struct mcontext __user *frame)
147{
148 unsafe_copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE, failed);
149 return 0;
150
151failed:
152 return 1;
153}
154
155static __always_inline
156int __unsafe_restore_general_regs(struct pt_regs *regs, struct mcontext __user *sr)
157{
158 /* copy up to but not including MSR */
159 unsafe_copy_from_user(regs, &sr->mc_gregs, PT_MSR * sizeof(elf_greg_t), failed);
160
161 /* copy from orig_r3 (the word after the MSR) up to the end */
162 unsafe_copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
163 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t), failed);
164
165 return 0;
166
167failed:
168 return 1;
169}
170#endif
171
172#define unsafe_save_general_regs(regs, frame, label) do { \
173 if (__unsafe_save_general_regs(regs, frame)) \
174 goto label; \
175} while (0)
176
177#define unsafe_restore_general_regs(regs, frame, label) do { \
178 if (__unsafe_restore_general_regs(regs, frame)) \
179 goto label; \
180} while (0)
181
182/*
183 * When we have signals to deliver, we set up on the
184 * user stack, going down from the original stack pointer:
185 * an ABI gap of 56 words
186 * an mcontext struct
187 * a sigcontext struct
188 * a gap of __SIGNAL_FRAMESIZE bytes
189 *
190 * Each of these things must be a multiple of 16 bytes in size. The following
191 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
192 *
193 */
194struct sigframe {
195 struct sigcontext sctx; /* the sigcontext */
196 struct mcontext mctx; /* all the register values */
197#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
198 struct sigcontext sctx_transact;
199 struct mcontext mctx_transact;
200#endif
201 /*
202 * Programs using the rs6000/xcoff abi can save up to 19 gp
203 * regs and 18 fp regs below sp before decrementing it.
204 */
205 int abigap[56];
206};
207
208/*
209 * When we have rt signals to deliver, we set up on the
210 * user stack, going down from the original stack pointer:
211 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
212 * a gap of __SIGNAL_FRAMESIZE+16 bytes
213 * (the +16 is to get the siginfo and ucontext in the same
214 * positions as in older kernels).
215 *
216 * Each of these things must be a multiple of 16 bytes in size.
217 *
218 */
219struct rt_sigframe {
220#ifdef CONFIG_PPC64
221 compat_siginfo_t info;
222#else
223 struct siginfo info;
224#endif
225 struct ucontext uc;
226#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
227 struct ucontext uc_transact;
228#endif
229 /*
230 * Programs using the rs6000/xcoff abi can save up to 19 gp
231 * regs and 18 fp regs below sp before decrementing it.
232 */
233 int abigap[56];
234};
235
236/*
237 * Save the current user registers on the user stack.
238 * We only save the altivec/spe registers if the process has used
239 * altivec/spe instructions at some point.
240 */
241static void prepare_save_user_regs(int ctx_has_vsx_region)
242{
243 /* Make sure floating point registers are stored in regs */
244 flush_fp_to_thread(current);
245#ifdef CONFIG_ALTIVEC
246 if (current->thread.used_vr)
247 flush_altivec_to_thread(current);
248 if (cpu_has_feature(CPU_FTR_ALTIVEC))
249 current->thread.vrsave = mfspr(SPRN_VRSAVE);
250#endif
251#ifdef CONFIG_VSX
252 if (current->thread.used_vsr && ctx_has_vsx_region)
253 flush_vsx_to_thread(current);
254#endif
255#ifdef CONFIG_SPE
256 if (current->thread.used_spe)
257 flush_spe_to_thread(current);
258#endif
259}
260
261static int __unsafe_save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
262 struct mcontext __user *tm_frame, int ctx_has_vsx_region)
263{
264 unsigned long msr = regs->msr;
265
266 /* save general registers */
267 unsafe_save_general_regs(regs, frame, failed);
268
269#ifdef CONFIG_ALTIVEC
270 /* save altivec registers */
271 if (current->thread.used_vr) {
272 unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
273 ELF_NVRREG * sizeof(vector128), failed);
274 /* set MSR_VEC in the saved MSR value to indicate that
275 frame->mc_vregs contains valid data */
276 msr |= MSR_VEC;
277 }
278 /* else assert((regs->msr & MSR_VEC) == 0) */
279
280 /* We always copy to/from vrsave, it's 0 if we don't have or don't
281 * use altivec. Since VSCR only contains 32 bits saved in the least
282 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
283 * most significant bits of that same vector. --BenH
284 * Note that the current VRSAVE value is in the SPR at this point.
285 */
286 unsafe_put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32],
287 failed);
288#endif /* CONFIG_ALTIVEC */
289 unsafe_copy_fpr_to_user(&frame->mc_fregs, current, failed);
290
291 /*
292 * Clear the MSR VSX bit to indicate there is no valid state attached
293 * to this context, except in the specific case below where we set it.
294 */
295 msr &= ~MSR_VSX;
296#ifdef CONFIG_VSX
297 /*
298 * Copy VSR 0-31 upper half from thread_struct to local
299 * buffer, then write that to userspace. Also set MSR_VSX in
300 * the saved MSR value to indicate that frame->mc_vregs
301 * contains valid data
302 */
303 if (current->thread.used_vsr && ctx_has_vsx_region) {
304 unsafe_copy_vsx_to_user(&frame->mc_vsregs, current, failed);
305 msr |= MSR_VSX;
306 }
307#endif /* CONFIG_VSX */
308#ifdef CONFIG_SPE
309 /* save spe registers */
310 if (current->thread.used_spe) {
311 unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
312 ELF_NEVRREG * sizeof(u32), failed);
313 /* set MSR_SPE in the saved MSR value to indicate that
314 frame->mc_vregs contains valid data */
315 msr |= MSR_SPE;
316 }
317 /* else assert((regs->msr & MSR_SPE) == 0) */
318
319 /* We always copy to/from spefscr */
320 unsafe_put_user(current->thread.spefscr,
321 (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
322#endif /* CONFIG_SPE */
323
324 unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
325
326 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
327 * can check it on the restore to see if TM is active
328 */
329 if (tm_frame)
330 unsafe_put_user(0, &tm_frame->mc_gregs[PT_MSR], failed);
331
332 return 0;
333
334failed:
335 return 1;
336}
337
338#define unsafe_save_user_regs(regs, frame, tm_frame, has_vsx, label) do { \
339 if (__unsafe_save_user_regs(regs, frame, tm_frame, has_vsx)) \
340 goto label; \
341} while (0)
342
343#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
344/*
345 * Save the current user registers on the user stack.
346 * We only save the altivec/spe registers if the process has used
347 * altivec/spe instructions at some point.
348 * We also save the transactional registers to a second ucontext in the
349 * frame.
350 *
351 * See __unsafe_save_user_regs() and signal_64.c:setup_tm_sigcontexts().
352 */
353static void prepare_save_tm_user_regs(void)
354{
355 WARN_ON(tm_suspend_disabled);
356
357 if (cpu_has_feature(CPU_FTR_ALTIVEC))
358 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
359}
360
361static int save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
362 struct mcontext __user *tm_frame, unsigned long msr)
363{
364 /* Save both sets of general registers */
365 unsafe_save_general_regs(¤t->thread.ckpt_regs, frame, failed);
366 unsafe_save_general_regs(regs, tm_frame, failed);
367
368 /* Stash the top half of the 64bit MSR into the 32bit MSR word
369 * of the transactional mcontext. This way we have a backward-compatible
370 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
371 * also look at what type of transaction (T or S) was active at the
372 * time of the signal.
373 */
374 unsafe_put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR], failed);
375
376 /* save altivec registers */
377 if (current->thread.used_vr) {
378 unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
379 ELF_NVRREG * sizeof(vector128), failed);
380 if (msr & MSR_VEC)
381 unsafe_copy_to_user(&tm_frame->mc_vregs,
382 ¤t->thread.vr_state,
383 ELF_NVRREG * sizeof(vector128), failed);
384 else
385 unsafe_copy_to_user(&tm_frame->mc_vregs,
386 ¤t->thread.ckvr_state,
387 ELF_NVRREG * sizeof(vector128), failed);
388
389 /* set MSR_VEC in the saved MSR value to indicate that
390 * frame->mc_vregs contains valid data
391 */
392 msr |= MSR_VEC;
393 }
394
395 /* We always copy to/from vrsave, it's 0 if we don't have or don't
396 * use altivec. Since VSCR only contains 32 bits saved in the least
397 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
398 * most significant bits of that same vector. --BenH
399 */
400 unsafe_put_user(current->thread.ckvrsave,
401 (u32 __user *)&frame->mc_vregs[32], failed);
402 if (msr & MSR_VEC)
403 unsafe_put_user(current->thread.vrsave,
404 (u32 __user *)&tm_frame->mc_vregs[32], failed);
405 else
406 unsafe_put_user(current->thread.ckvrsave,
407 (u32 __user *)&tm_frame->mc_vregs[32], failed);
408
409 unsafe_copy_ckfpr_to_user(&frame->mc_fregs, current, failed);
410 if (msr & MSR_FP)
411 unsafe_copy_fpr_to_user(&tm_frame->mc_fregs, current, failed);
412 else
413 unsafe_copy_ckfpr_to_user(&tm_frame->mc_fregs, current, failed);
414
415 /*
416 * Copy VSR 0-31 upper half from thread_struct to local
417 * buffer, then write that to userspace. Also set MSR_VSX in
418 * the saved MSR value to indicate that frame->mc_vregs
419 * contains valid data
420 */
421 if (current->thread.used_vsr) {
422 unsafe_copy_ckvsx_to_user(&frame->mc_vsregs, current, failed);
423 if (msr & MSR_VSX)
424 unsafe_copy_vsx_to_user(&tm_frame->mc_vsregs, current, failed);
425 else
426 unsafe_copy_ckvsx_to_user(&tm_frame->mc_vsregs, current, failed);
427
428 msr |= MSR_VSX;
429 }
430
431 unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
432
433 return 0;
434
435failed:
436 return 1;
437}
438#else
439static void prepare_save_tm_user_regs(void) { }
440
441static int save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
442 struct mcontext __user *tm_frame, unsigned long msr)
443{
444 return 0;
445}
446#endif
447
448#define unsafe_save_tm_user_regs(regs, frame, tm_frame, msr, label) do { \
449 if (save_tm_user_regs_unsafe(regs, frame, tm_frame, msr)) \
450 goto label; \
451} while (0)
452
453/*
454 * Restore the current user register values from the user stack,
455 * (except for MSR).
456 */
457static long restore_user_regs(struct pt_regs *regs,
458 struct mcontext __user *sr, int sig)
459{
460 unsigned int save_r2 = 0;
461 unsigned long msr;
462#ifdef CONFIG_VSX
463 int i;
464#endif
465
466 if (!user_read_access_begin(sr, sizeof(*sr)))
467 return 1;
468 /*
469 * restore general registers but not including MSR or SOFTE. Also
470 * take care of keeping r2 (TLS) intact if not a signal
471 */
472 if (!sig)
473 save_r2 = (unsigned int)regs->gpr[2];
474 unsafe_restore_general_regs(regs, sr, failed);
475 set_trap_norestart(regs);
476 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
477 if (!sig)
478 regs->gpr[2] = (unsigned long) save_r2;
479
480 /* if doing signal return, restore the previous little-endian mode */
481 if (sig)
482 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (msr & MSR_LE));
483
484#ifdef CONFIG_ALTIVEC
485 /*
486 * Force the process to reload the altivec registers from
487 * current->thread when it next does altivec instructions
488 */
489 regs_set_return_msr(regs, regs->msr & ~MSR_VEC);
490 if (msr & MSR_VEC) {
491 /* restore altivec registers from the stack */
492 unsafe_copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
493 sizeof(sr->mc_vregs), failed);
494 current->thread.used_vr = true;
495 } else if (current->thread.used_vr)
496 memset(¤t->thread.vr_state, 0,
497 ELF_NVRREG * sizeof(vector128));
498
499 /* Always get VRSAVE back */
500 unsafe_get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32], failed);
501 if (cpu_has_feature(CPU_FTR_ALTIVEC))
502 mtspr(SPRN_VRSAVE, current->thread.vrsave);
503#endif /* CONFIG_ALTIVEC */
504 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
505
506#ifdef CONFIG_VSX
507 /*
508 * Force the process to reload the VSX registers from
509 * current->thread when it next does VSX instruction.
510 */
511 regs_set_return_msr(regs, regs->msr & ~MSR_VSX);
512 if (msr & MSR_VSX) {
513 /*
514 * Restore altivec registers from the stack to a local
515 * buffer, then write this out to the thread_struct
516 */
517 unsafe_copy_vsx_from_user(current, &sr->mc_vsregs, failed);
518 current->thread.used_vsr = true;
519 } else if (current->thread.used_vsr)
520 for (i = 0; i < 32 ; i++)
521 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
522#endif /* CONFIG_VSX */
523 /*
524 * force the process to reload the FP registers from
525 * current->thread when it next does FP instructions
526 */
527 regs_set_return_msr(regs, regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1));
528
529#ifdef CONFIG_SPE
530 /* force the process to reload the spe registers from
531 current->thread when it next does spe instructions */
532 regs_set_return_msr(regs, regs->msr & ~MSR_SPE);
533 if (msr & MSR_SPE) {
534 /* restore spe registers from the stack */
535 unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs,
536 ELF_NEVRREG * sizeof(u32), failed);
537 current->thread.used_spe = true;
538 } else if (current->thread.used_spe)
539 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
540
541 /* Always get SPEFSCR back */
542 unsafe_get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG, failed);
543#endif /* CONFIG_SPE */
544
545 user_read_access_end();
546 return 0;
547
548failed:
549 user_read_access_end();
550 return 1;
551}
552
553#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
554/*
555 * Restore the current user register values from the user stack, except for
556 * MSR, and recheckpoint the original checkpointed register state for processes
557 * in transactions.
558 */
559static long restore_tm_user_regs(struct pt_regs *regs,
560 struct mcontext __user *sr,
561 struct mcontext __user *tm_sr)
562{
563 unsigned long msr, msr_hi;
564 int i;
565
566 if (tm_suspend_disabled)
567 return 1;
568 /*
569 * restore general registers but not including MSR or SOFTE. Also
570 * take care of keeping r2 (TLS) intact if not a signal.
571 * See comment in signal_64.c:restore_tm_sigcontexts();
572 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
573 * were set by the signal delivery.
574 */
575 if (!user_read_access_begin(sr, sizeof(*sr)))
576 return 1;
577
578 unsafe_restore_general_regs(¤t->thread.ckpt_regs, sr, failed);
579 unsafe_get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP], failed);
580 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
581
582 /* Restore the previous little-endian mode */
583 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (msr & MSR_LE));
584
585 regs_set_return_msr(regs, regs->msr & ~MSR_VEC);
586 if (msr & MSR_VEC) {
587 /* restore altivec registers from the stack */
588 unsafe_copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
589 sizeof(sr->mc_vregs), failed);
590 current->thread.used_vr = true;
591 } else if (current->thread.used_vr) {
592 memset(¤t->thread.vr_state, 0,
593 ELF_NVRREG * sizeof(vector128));
594 memset(¤t->thread.ckvr_state, 0,
595 ELF_NVRREG * sizeof(vector128));
596 }
597
598 /* Always get VRSAVE back */
599 unsafe_get_user(current->thread.ckvrsave,
600 (u32 __user *)&sr->mc_vregs[32], failed);
601 if (cpu_has_feature(CPU_FTR_ALTIVEC))
602 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
603
604 regs_set_return_msr(regs, regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1));
605
606 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
607
608 regs_set_return_msr(regs, regs->msr & ~MSR_VSX);
609 if (msr & MSR_VSX) {
610 /*
611 * Restore altivec registers from the stack to a local
612 * buffer, then write this out to the thread_struct
613 */
614 unsafe_copy_ckvsx_from_user(current, &sr->mc_vsregs, failed);
615 current->thread.used_vsr = true;
616 } else if (current->thread.used_vsr)
617 for (i = 0; i < 32 ; i++) {
618 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
619 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
620 }
621
622 user_read_access_end();
623
624 if (!user_read_access_begin(tm_sr, sizeof(*tm_sr)))
625 return 1;
626
627 unsafe_restore_general_regs(regs, tm_sr, failed);
628
629 /* restore altivec registers from the stack */
630 if (msr & MSR_VEC)
631 unsafe_copy_from_user(¤t->thread.vr_state, &tm_sr->mc_vregs,
632 sizeof(sr->mc_vregs), failed);
633
634 /* Always get VRSAVE back */
635 unsafe_get_user(current->thread.vrsave,
636 (u32 __user *)&tm_sr->mc_vregs[32], failed);
637
638 unsafe_copy_ckfpr_from_user(current, &tm_sr->mc_fregs, failed);
639
640 if (msr & MSR_VSX) {
641 /*
642 * Restore altivec registers from the stack to a local
643 * buffer, then write this out to the thread_struct
644 */
645 unsafe_copy_vsx_from_user(current, &tm_sr->mc_vsregs, failed);
646 current->thread.used_vsr = true;
647 }
648
649 /* Get the top half of the MSR from the user context */
650 unsafe_get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR], failed);
651 msr_hi <<= 32;
652
653 user_read_access_end();
654
655 /* If TM bits are set to the reserved value, it's an invalid context */
656 if (MSR_TM_RESV(msr_hi))
657 return 1;
658
659 /*
660 * Disabling preemption, since it is unsafe to be preempted
661 * with MSR[TS] set without recheckpointing.
662 */
663 preempt_disable();
664
665 /*
666 * CAUTION:
667 * After regs->MSR[TS] being updated, make sure that get_user(),
668 * put_user() or similar functions are *not* called. These
669 * functions can generate page faults which will cause the process
670 * to be de-scheduled with MSR[TS] set but without calling
671 * tm_recheckpoint(). This can cause a bug.
672 *
673 * Pull in the MSR TM bits from the user context
674 */
675 regs_set_return_msr(regs, (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK));
676 /* Now, recheckpoint. This loads up all of the checkpointed (older)
677 * registers, including FP and V[S]Rs. After recheckpointing, the
678 * transactional versions should be loaded.
679 */
680 tm_enable();
681 /* Make sure the transaction is marked as failed */
682 current->thread.tm_texasr |= TEXASR_FS;
683 /* This loads the checkpointed FP/VEC state, if used */
684 tm_recheckpoint(¤t->thread);
685
686 /* This loads the speculative FP/VEC state, if used */
687 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
688 if (msr & MSR_FP) {
689 load_fp_state(¤t->thread.fp_state);
690 regs_set_return_msr(regs, regs->msr | (MSR_FP | current->thread.fpexc_mode));
691 }
692 if (msr & MSR_VEC) {
693 load_vr_state(¤t->thread.vr_state);
694 regs_set_return_msr(regs, regs->msr | MSR_VEC);
695 }
696
697 preempt_enable();
698
699 return 0;
700
701failed:
702 user_read_access_end();
703 return 1;
704}
705#else
706static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *sr,
707 struct mcontext __user *tm_sr)
708{
709 return 0;
710}
711#endif
712
713#ifdef CONFIG_PPC64
714
715#define copy_siginfo_to_user copy_siginfo_to_user32
716
717#endif /* CONFIG_PPC64 */
718
719/*
720 * Set up a signal frame for a "real-time" signal handler
721 * (one which gets siginfo).
722 */
723int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
724 struct task_struct *tsk)
725{
726 struct rt_sigframe __user *frame;
727 struct mcontext __user *mctx;
728 struct mcontext __user *tm_mctx = NULL;
729 unsigned long newsp = 0;
730 unsigned long tramp;
731 struct pt_regs *regs = tsk->thread.regs;
732 /* Save the thread's msr before get_tm_stackpointer() changes it */
733 unsigned long msr = regs->msr;
734
735 /* Set up Signal Frame */
736 frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
737 mctx = &frame->uc.uc_mcontext;
738#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
739 tm_mctx = &frame->uc_transact.uc_mcontext;
740#endif
741 if (MSR_TM_ACTIVE(msr))
742 prepare_save_tm_user_regs();
743 else
744 prepare_save_user_regs(1);
745
746 if (!user_access_begin(frame, sizeof(*frame)))
747 goto badframe;
748
749 /* Put the siginfo & fill in most of the ucontext */
750 unsafe_put_user(0, &frame->uc.uc_flags, failed);
751#ifdef CONFIG_PPC64
752 unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
753#else
754 unsafe_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
755#endif
756 unsafe_put_user(to_user_ptr(&frame->uc.uc_mcontext), &frame->uc.uc_regs, failed);
757
758 if (MSR_TM_ACTIVE(msr)) {
759#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
760 unsafe_put_user((unsigned long)&frame->uc_transact,
761 &frame->uc.uc_link, failed);
762 unsafe_put_user((unsigned long)tm_mctx,
763 &frame->uc_transact.uc_regs, failed);
764#endif
765 unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
766 } else {
767 unsafe_put_user(0, &frame->uc.uc_link, failed);
768 unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
769 }
770
771 /* Save user registers on the stack */
772 if (tsk->mm->context.vdso) {
773 tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp_rt32);
774 } else {
775 tramp = (unsigned long)mctx->mc_pad;
776 unsafe_put_user(PPC_RAW_LI(_R0, __NR_rt_sigreturn), &mctx->mc_pad[0], failed);
777 unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
778 asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
779 }
780 unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed);
781
782 user_access_end();
783
784 if (copy_siginfo_to_user(&frame->info, &ksig->info))
785 goto badframe;
786
787 regs->link = tramp;
788
789#ifdef CONFIG_PPC_FPU_REGS
790 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
791#endif
792
793 /* create a stack frame for the caller of the handler */
794 newsp = ((unsigned long)frame) - (__SIGNAL_FRAMESIZE + 16);
795 if (put_user(regs->gpr[1], (u32 __user *)newsp))
796 goto badframe;
797
798 /* Fill registers for signal handler */
799 regs->gpr[1] = newsp;
800 regs->gpr[3] = ksig->sig;
801 regs->gpr[4] = (unsigned long)&frame->info;
802 regs->gpr[5] = (unsigned long)&frame->uc;
803 regs->gpr[6] = (unsigned long)frame;
804 regs_set_return_ip(regs, (unsigned long) ksig->ka.sa.sa_handler);
805 /* enter the signal handler in native-endian mode */
806 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (MSR_KERNEL & MSR_LE));
807
808 return 0;
809
810failed:
811 user_access_end();
812
813badframe:
814 signal_fault(tsk, regs, "handle_rt_signal32", frame);
815
816 return 1;
817}
818
819/*
820 * OK, we're invoking a handler
821 */
822int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
823 struct task_struct *tsk)
824{
825 struct sigcontext __user *sc;
826 struct sigframe __user *frame;
827 struct mcontext __user *mctx;
828 struct mcontext __user *tm_mctx = NULL;
829 unsigned long newsp = 0;
830 unsigned long tramp;
831 struct pt_regs *regs = tsk->thread.regs;
832 /* Save the thread's msr before get_tm_stackpointer() changes it */
833 unsigned long msr = regs->msr;
834
835 /* Set up Signal Frame */
836 frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
837 mctx = &frame->mctx;
838#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
839 tm_mctx = &frame->mctx_transact;
840#endif
841 if (MSR_TM_ACTIVE(msr))
842 prepare_save_tm_user_regs();
843 else
844 prepare_save_user_regs(1);
845
846 if (!user_access_begin(frame, sizeof(*frame)))
847 goto badframe;
848 sc = (struct sigcontext __user *) &frame->sctx;
849
850#if _NSIG != 64
851#error "Please adjust handle_signal()"
852#endif
853 unsafe_put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler, failed);
854 unsafe_put_user(oldset->sig[0], &sc->oldmask, failed);
855#ifdef CONFIG_PPC64
856 unsafe_put_user((oldset->sig[0] >> 32), &sc->_unused[3], failed);
857#else
858 unsafe_put_user(oldset->sig[1], &sc->_unused[3], failed);
859#endif
860 unsafe_put_user(to_user_ptr(mctx), &sc->regs, failed);
861 unsafe_put_user(ksig->sig, &sc->signal, failed);
862
863 if (MSR_TM_ACTIVE(msr))
864 unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
865 else
866 unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
867
868 if (tsk->mm->context.vdso) {
869 tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp32);
870 } else {
871 tramp = (unsigned long)mctx->mc_pad;
872 unsafe_put_user(PPC_RAW_LI(_R0, __NR_sigreturn), &mctx->mc_pad[0], failed);
873 unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
874 asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
875 }
876 user_access_end();
877
878 regs->link = tramp;
879
880#ifdef CONFIG_PPC_FPU_REGS
881 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
882#endif
883
884 /* create a stack frame for the caller of the handler */
885 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
886 if (put_user(regs->gpr[1], (u32 __user *)newsp))
887 goto badframe;
888
889 regs->gpr[1] = newsp;
890 regs->gpr[3] = ksig->sig;
891 regs->gpr[4] = (unsigned long) sc;
892 regs_set_return_ip(regs, (unsigned long) ksig->ka.sa.sa_handler);
893 /* enter the signal handler in native-endian mode */
894 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (MSR_KERNEL & MSR_LE));
895
896 return 0;
897
898failed:
899 user_access_end();
900
901badframe:
902 signal_fault(tsk, regs, "handle_signal32", frame);
903
904 return 1;
905}
906
907static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
908{
909 sigset_t set;
910 struct mcontext __user *mcp;
911
912 if (!user_read_access_begin(ucp, sizeof(*ucp)))
913 return -EFAULT;
914
915 unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
916#ifdef CONFIG_PPC64
917 {
918 u32 cmcp;
919
920 unsafe_get_user(cmcp, &ucp->uc_regs, failed);
921 mcp = (struct mcontext __user *)(u64)cmcp;
922 }
923#else
924 unsafe_get_user(mcp, &ucp->uc_regs, failed);
925#endif
926 user_read_access_end();
927
928 set_current_blocked(&set);
929 if (restore_user_regs(regs, mcp, sig))
930 return -EFAULT;
931
932 return 0;
933
934failed:
935 user_read_access_end();
936 return -EFAULT;
937}
938
939#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
940static int do_setcontext_tm(struct ucontext __user *ucp,
941 struct ucontext __user *tm_ucp,
942 struct pt_regs *regs)
943{
944 sigset_t set;
945 struct mcontext __user *mcp;
946 struct mcontext __user *tm_mcp;
947 u32 cmcp;
948 u32 tm_cmcp;
949
950 if (!user_read_access_begin(ucp, sizeof(*ucp)))
951 return -EFAULT;
952
953 unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
954 unsafe_get_user(cmcp, &ucp->uc_regs, failed);
955
956 user_read_access_end();
957
958 if (__get_user(tm_cmcp, &tm_ucp->uc_regs))
959 return -EFAULT;
960 mcp = (struct mcontext __user *)(u64)cmcp;
961 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
962 /* no need to check access_ok(mcp), since mcp < 4GB */
963
964 set_current_blocked(&set);
965 if (restore_tm_user_regs(regs, mcp, tm_mcp))
966 return -EFAULT;
967
968 return 0;
969
970failed:
971 user_read_access_end();
972 return -EFAULT;
973}
974#endif
975
976#ifdef CONFIG_PPC64
977COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
978 struct ucontext __user *, new_ctx, int, ctx_size)
979#else
980SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
981 struct ucontext __user *, new_ctx, long, ctx_size)
982#endif
983{
984 struct pt_regs *regs = current_pt_regs();
985 int ctx_has_vsx_region = 0;
986
987#ifdef CONFIG_PPC64
988 unsigned long new_msr = 0;
989
990 if (new_ctx) {
991 struct mcontext __user *mcp;
992 u32 cmcp;
993
994 /*
995 * Get pointer to the real mcontext. No need for
996 * access_ok since we are dealing with compat
997 * pointers.
998 */
999 if (__get_user(cmcp, &new_ctx->uc_regs))
1000 return -EFAULT;
1001 mcp = (struct mcontext __user *)(u64)cmcp;
1002 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1003 return -EFAULT;
1004 }
1005 /*
1006 * Check that the context is not smaller than the original
1007 * size (with VMX but without VSX)
1008 */
1009 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1010 return -EINVAL;
1011 /*
1012 * If the new context state sets the MSR VSX bits but
1013 * it doesn't provide VSX state.
1014 */
1015 if ((ctx_size < sizeof(struct ucontext)) &&
1016 (new_msr & MSR_VSX))
1017 return -EINVAL;
1018 /* Does the context have enough room to store VSX data? */
1019 if (ctx_size >= sizeof(struct ucontext))
1020 ctx_has_vsx_region = 1;
1021#else
1022 /* Context size is for future use. Right now, we only make sure
1023 * we are passed something we understand
1024 */
1025 if (ctx_size < sizeof(struct ucontext))
1026 return -EINVAL;
1027#endif
1028 if (old_ctx != NULL) {
1029 struct mcontext __user *mctx;
1030
1031 /*
1032 * old_ctx might not be 16-byte aligned, in which
1033 * case old_ctx->uc_mcontext won't be either.
1034 * Because we have the old_ctx->uc_pad2 field
1035 * before old_ctx->uc_mcontext, we need to round down
1036 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1037 */
1038 mctx = (struct mcontext __user *)
1039 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1040 prepare_save_user_regs(ctx_has_vsx_region);
1041 if (!user_write_access_begin(old_ctx, ctx_size))
1042 return -EFAULT;
1043 unsafe_save_user_regs(regs, mctx, NULL, ctx_has_vsx_region, failed);
1044 unsafe_put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked, failed);
1045 unsafe_put_user(to_user_ptr(mctx), &old_ctx->uc_regs, failed);
1046 user_write_access_end();
1047 }
1048 if (new_ctx == NULL)
1049 return 0;
1050 if (!access_ok(new_ctx, ctx_size) ||
1051 fault_in_pages_readable((u8 __user *)new_ctx, ctx_size))
1052 return -EFAULT;
1053
1054 /*
1055 * If we get a fault copying the context into the kernel's
1056 * image of the user's registers, we can't just return -EFAULT
1057 * because the user's registers will be corrupted. For instance
1058 * the NIP value may have been updated but not some of the
1059 * other registers. Given that we have done the access_ok
1060 * and successfully read the first and last bytes of the region
1061 * above, this should only happen in an out-of-memory situation
1062 * or if another thread unmaps the region containing the context.
1063 * We kill the task with a SIGSEGV in this situation.
1064 */
1065 if (do_setcontext(new_ctx, regs, 0))
1066 do_exit(SIGSEGV);
1067
1068 set_thread_flag(TIF_RESTOREALL);
1069 return 0;
1070
1071failed:
1072 user_write_access_end();
1073 return -EFAULT;
1074}
1075
1076#ifdef CONFIG_PPC64
1077COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1078#else
1079SYSCALL_DEFINE0(rt_sigreturn)
1080#endif
1081{
1082 struct rt_sigframe __user *rt_sf;
1083 struct pt_regs *regs = current_pt_regs();
1084 int tm_restore = 0;
1085#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1086 struct ucontext __user *uc_transact;
1087 unsigned long msr_hi;
1088 unsigned long tmp;
1089#endif
1090 /* Always make any pending restarted system calls return -EINTR */
1091 current->restart_block.fn = do_no_restart_syscall;
1092
1093 rt_sf = (struct rt_sigframe __user *)
1094 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1095 if (!access_ok(rt_sf, sizeof(*rt_sf)))
1096 goto bad;
1097
1098#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1099 /*
1100 * If there is a transactional state then throw it away.
1101 * The purpose of a sigreturn is to destroy all traces of the
1102 * signal frame, this includes any transactional state created
1103 * within in. We only check for suspended as we can never be
1104 * active in the kernel, we are active, there is nothing better to
1105 * do than go ahead and Bad Thing later.
1106 * The cause is not important as there will never be a
1107 * recheckpoint so it's not user visible.
1108 */
1109 if (MSR_TM_SUSPENDED(mfmsr()))
1110 tm_reclaim_current(0);
1111
1112 if (__get_user(tmp, &rt_sf->uc.uc_link))
1113 goto bad;
1114 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1115 if (uc_transact) {
1116 u32 cmcp;
1117 struct mcontext __user *mcp;
1118
1119 if (__get_user(cmcp, &uc_transact->uc_regs))
1120 return -EFAULT;
1121 mcp = (struct mcontext __user *)(u64)cmcp;
1122 /* The top 32 bits of the MSR are stashed in the transactional
1123 * ucontext. */
1124 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1125 goto bad;
1126
1127 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1128 /* Trying to start TM on non TM system */
1129 if (!cpu_has_feature(CPU_FTR_TM))
1130 goto bad;
1131 /* We only recheckpoint on return if we're
1132 * transaction.
1133 */
1134 tm_restore = 1;
1135 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1136 goto bad;
1137 }
1138 }
1139 if (!tm_restore) {
1140 /*
1141 * Unset regs->msr because ucontext MSR TS is not
1142 * set, and recheckpoint was not called. This avoid
1143 * hitting a TM Bad thing at RFID
1144 */
1145 regs_set_return_msr(regs, regs->msr & ~MSR_TS_MASK);
1146 }
1147 /* Fall through, for non-TM restore */
1148#endif
1149 if (!tm_restore)
1150 if (do_setcontext(&rt_sf->uc, regs, 1))
1151 goto bad;
1152
1153 /*
1154 * It's not clear whether or why it is desirable to save the
1155 * sigaltstack setting on signal delivery and restore it on
1156 * signal return. But other architectures do this and we have
1157 * always done it up until now so it is probably better not to
1158 * change it. -- paulus
1159 */
1160#ifdef CONFIG_PPC64
1161 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1162 goto bad;
1163#else
1164 if (restore_altstack(&rt_sf->uc.uc_stack))
1165 goto bad;
1166#endif
1167 set_thread_flag(TIF_RESTOREALL);
1168 return 0;
1169
1170 bad:
1171 signal_fault(current, regs, "sys_rt_sigreturn", rt_sf);
1172
1173 force_sig(SIGSEGV);
1174 return 0;
1175}
1176
1177#ifdef CONFIG_PPC32
1178SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1179 int, ndbg, struct sig_dbg_op __user *, dbg)
1180{
1181 struct pt_regs *regs = current_pt_regs();
1182 struct sig_dbg_op op;
1183 int i;
1184 unsigned long new_msr = regs->msr;
1185#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1186 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1187#endif
1188
1189 for (i=0; i<ndbg; i++) {
1190 if (copy_from_user(&op, dbg + i, sizeof(op)))
1191 return -EFAULT;
1192 switch (op.dbg_type) {
1193 case SIG_DBG_SINGLE_STEPPING:
1194#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1195 if (op.dbg_value) {
1196 new_msr |= MSR_DE;
1197 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1198 } else {
1199 new_dbcr0 &= ~DBCR0_IC;
1200 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1201 current->thread.debug.dbcr1)) {
1202 new_msr &= ~MSR_DE;
1203 new_dbcr0 &= ~DBCR0_IDM;
1204 }
1205 }
1206#else
1207 if (op.dbg_value)
1208 new_msr |= MSR_SE;
1209 else
1210 new_msr &= ~MSR_SE;
1211#endif
1212 break;
1213 case SIG_DBG_BRANCH_TRACING:
1214#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1215 return -EINVAL;
1216#else
1217 if (op.dbg_value)
1218 new_msr |= MSR_BE;
1219 else
1220 new_msr &= ~MSR_BE;
1221#endif
1222 break;
1223
1224 default:
1225 return -EINVAL;
1226 }
1227 }
1228
1229 /* We wait until here to actually install the values in the
1230 registers so if we fail in the above loop, it will not
1231 affect the contents of these registers. After this point,
1232 failure is a problem, anyway, and it's very unlikely unless
1233 the user is really doing something wrong. */
1234 regs_set_return_msr(regs, new_msr);
1235#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1236 current->thread.debug.dbcr0 = new_dbcr0;
1237#endif
1238
1239 if (!access_ok(ctx, sizeof(*ctx)) ||
1240 fault_in_pages_readable((u8 __user *)ctx, sizeof(*ctx)))
1241 return -EFAULT;
1242
1243 /*
1244 * If we get a fault copying the context into the kernel's
1245 * image of the user's registers, we can't just return -EFAULT
1246 * because the user's registers will be corrupted. For instance
1247 * the NIP value may have been updated but not some of the
1248 * other registers. Given that we have done the access_ok
1249 * and successfully read the first and last bytes of the region
1250 * above, this should only happen in an out-of-memory situation
1251 * or if another thread unmaps the region containing the context.
1252 * We kill the task with a SIGSEGV in this situation.
1253 */
1254 if (do_setcontext(ctx, regs, 1)) {
1255 signal_fault(current, regs, "sys_debug_setcontext", ctx);
1256
1257 force_sig(SIGSEGV);
1258 goto out;
1259 }
1260
1261 /*
1262 * It's not clear whether or why it is desirable to save the
1263 * sigaltstack setting on signal delivery and restore it on
1264 * signal return. But other architectures do this and we have
1265 * always done it up until now so it is probably better not to
1266 * change it. -- paulus
1267 */
1268 restore_altstack(&ctx->uc_stack);
1269
1270 set_thread_flag(TIF_RESTOREALL);
1271 out:
1272 return 0;
1273}
1274#endif
1275
1276/*
1277 * Do a signal return; undo the signal stack.
1278 */
1279#ifdef CONFIG_PPC64
1280COMPAT_SYSCALL_DEFINE0(sigreturn)
1281#else
1282SYSCALL_DEFINE0(sigreturn)
1283#endif
1284{
1285 struct pt_regs *regs = current_pt_regs();
1286 struct sigframe __user *sf;
1287 struct sigcontext __user *sc;
1288 struct sigcontext sigctx;
1289 struct mcontext __user *sr;
1290 sigset_t set;
1291 struct mcontext __user *mcp;
1292 struct mcontext __user *tm_mcp = NULL;
1293 unsigned long long msr_hi = 0;
1294
1295 /* Always make any pending restarted system calls return -EINTR */
1296 current->restart_block.fn = do_no_restart_syscall;
1297
1298 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1299 sc = &sf->sctx;
1300 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1301 goto badframe;
1302
1303#ifdef CONFIG_PPC64
1304 /*
1305 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1306 * unused part of the signal stackframe
1307 */
1308 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1309#else
1310 set.sig[0] = sigctx.oldmask;
1311 set.sig[1] = sigctx._unused[3];
1312#endif
1313 set_current_blocked(&set);
1314
1315 mcp = (struct mcontext __user *)&sf->mctx;
1316#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1317 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1318 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1319 goto badframe;
1320#endif
1321 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1322 if (!cpu_has_feature(CPU_FTR_TM))
1323 goto badframe;
1324 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1325 goto badframe;
1326 } else {
1327 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1328 if (restore_user_regs(regs, sr, 1)) {
1329 signal_fault(current, regs, "sys_sigreturn", sr);
1330
1331 force_sig(SIGSEGV);
1332 return 0;
1333 }
1334 }
1335
1336 set_thread_flag(TIF_RESTOREALL);
1337 return 0;
1338
1339badframe:
1340 signal_fault(current, regs, "sys_sigreturn", sc);
1341
1342 force_sig(SIGSEGV);
1343 return 0;
1344}
1/*
2 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
3 *
4 * PowerPC version
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Copyright (C) 2001 IBM
7 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
9 *
10 * Derived from "arch/i386/kernel/signal.c"
11 * Copyright (C) 1991, 1992 Linus Torvalds
12 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 */
19
20#include <linux/sched.h>
21#include <linux/mm.h>
22#include <linux/smp.h>
23#include <linux/kernel.h>
24#include <linux/signal.h>
25#include <linux/errno.h>
26#include <linux/elf.h>
27#include <linux/ptrace.h>
28#include <linux/ratelimit.h>
29#ifdef CONFIG_PPC64
30#include <linux/syscalls.h>
31#include <linux/compat.h>
32#else
33#include <linux/wait.h>
34#include <linux/unistd.h>
35#include <linux/stddef.h>
36#include <linux/tty.h>
37#include <linux/binfmts.h>
38#include <linux/freezer.h>
39#endif
40
41#include <asm/uaccess.h>
42#include <asm/cacheflush.h>
43#include <asm/syscalls.h>
44#include <asm/sigcontext.h>
45#include <asm/vdso.h>
46#include <asm/switch_to.h>
47#ifdef CONFIG_PPC64
48#include "ppc32.h"
49#include <asm/unistd.h>
50#else
51#include <asm/ucontext.h>
52#include <asm/pgtable.h>
53#endif
54
55#include "signal.h"
56
57#undef DEBUG_SIG
58
59#ifdef CONFIG_PPC64
60#define sys_sigsuspend compat_sys_sigsuspend
61#define sys_rt_sigsuspend compat_sys_rt_sigsuspend
62#define sys_rt_sigreturn compat_sys_rt_sigreturn
63#define sys_sigaction compat_sys_sigaction
64#define sys_swapcontext compat_sys_swapcontext
65#define sys_sigreturn compat_sys_sigreturn
66
67#define old_sigaction old_sigaction32
68#define sigcontext sigcontext32
69#define mcontext mcontext32
70#define ucontext ucontext32
71
72/*
73 * Userspace code may pass a ucontext which doesn't include VSX added
74 * at the end. We need to check for this case.
75 */
76#define UCONTEXTSIZEWITHOUTVSX \
77 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
78
79/*
80 * Returning 0 means we return to userspace via
81 * ret_from_except and thus restore all user
82 * registers from *regs. This is what we need
83 * to do when a signal has been delivered.
84 */
85
86#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
87#undef __SIGNAL_FRAMESIZE
88#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
89#undef ELF_NVRREG
90#define ELF_NVRREG ELF_NVRREG32
91
92/*
93 * Functions for flipping sigsets (thanks to brain dead generic
94 * implementation that makes things simple for little endian only)
95 */
96static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
97{
98 compat_sigset_t cset;
99
100 switch (_NSIG_WORDS) {
101 case 4: cset.sig[6] = set->sig[3] & 0xffffffffull;
102 cset.sig[7] = set->sig[3] >> 32;
103 case 3: cset.sig[4] = set->sig[2] & 0xffffffffull;
104 cset.sig[5] = set->sig[2] >> 32;
105 case 2: cset.sig[2] = set->sig[1] & 0xffffffffull;
106 cset.sig[3] = set->sig[1] >> 32;
107 case 1: cset.sig[0] = set->sig[0] & 0xffffffffull;
108 cset.sig[1] = set->sig[0] >> 32;
109 }
110 return copy_to_user(uset, &cset, sizeof(*uset));
111}
112
113static inline int get_sigset_t(sigset_t *set,
114 const compat_sigset_t __user *uset)
115{
116 compat_sigset_t s32;
117
118 if (copy_from_user(&s32, uset, sizeof(*uset)))
119 return -EFAULT;
120
121 /*
122 * Swap the 2 words of the 64-bit sigset_t (they are stored
123 * in the "wrong" endian in 32-bit user storage).
124 */
125 switch (_NSIG_WORDS) {
126 case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
127 case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
128 case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
129 case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
130 }
131 return 0;
132}
133
134static inline int get_old_sigaction(struct k_sigaction *new_ka,
135 struct old_sigaction __user *act)
136{
137 compat_old_sigset_t mask;
138 compat_uptr_t handler, restorer;
139
140 if (get_user(handler, &act->sa_handler) ||
141 __get_user(restorer, &act->sa_restorer) ||
142 __get_user(new_ka->sa.sa_flags, &act->sa_flags) ||
143 __get_user(mask, &act->sa_mask))
144 return -EFAULT;
145 new_ka->sa.sa_handler = compat_ptr(handler);
146 new_ka->sa.sa_restorer = compat_ptr(restorer);
147 siginitset(&new_ka->sa.sa_mask, mask);
148 return 0;
149}
150
151#define to_user_ptr(p) ptr_to_compat(p)
152#define from_user_ptr(p) compat_ptr(p)
153
154static inline int save_general_regs(struct pt_regs *regs,
155 struct mcontext __user *frame)
156{
157 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
158 int i;
159
160 WARN_ON(!FULL_REGS(regs));
161
162 for (i = 0; i <= PT_RESULT; i ++) {
163 if (i == 14 && !FULL_REGS(regs))
164 i = 32;
165 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
166 return -EFAULT;
167 }
168 return 0;
169}
170
171static inline int restore_general_regs(struct pt_regs *regs,
172 struct mcontext __user *sr)
173{
174 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
175 int i;
176
177 for (i = 0; i <= PT_RESULT; i++) {
178 if ((i == PT_MSR) || (i == PT_SOFTE))
179 continue;
180 if (__get_user(gregs[i], &sr->mc_gregs[i]))
181 return -EFAULT;
182 }
183 return 0;
184}
185
186#else /* CONFIG_PPC64 */
187
188#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
189
190static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
191{
192 return copy_to_user(uset, set, sizeof(*uset));
193}
194
195static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
196{
197 return copy_from_user(set, uset, sizeof(*uset));
198}
199
200static inline int get_old_sigaction(struct k_sigaction *new_ka,
201 struct old_sigaction __user *act)
202{
203 old_sigset_t mask;
204
205 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
206 __get_user(new_ka->sa.sa_handler, &act->sa_handler) ||
207 __get_user(new_ka->sa.sa_restorer, &act->sa_restorer) ||
208 __get_user(new_ka->sa.sa_flags, &act->sa_flags) ||
209 __get_user(mask, &act->sa_mask))
210 return -EFAULT;
211 siginitset(&new_ka->sa.sa_mask, mask);
212 return 0;
213}
214
215#define to_user_ptr(p) ((unsigned long)(p))
216#define from_user_ptr(p) ((void __user *)(p))
217
218static inline int save_general_regs(struct pt_regs *regs,
219 struct mcontext __user *frame)
220{
221 WARN_ON(!FULL_REGS(regs));
222 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
223}
224
225static inline int restore_general_regs(struct pt_regs *regs,
226 struct mcontext __user *sr)
227{
228 /* copy up to but not including MSR */
229 if (__copy_from_user(regs, &sr->mc_gregs,
230 PT_MSR * sizeof(elf_greg_t)))
231 return -EFAULT;
232 /* copy from orig_r3 (the word after the MSR) up to the end */
233 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
234 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
235 return -EFAULT;
236 return 0;
237}
238
239#endif /* CONFIG_PPC64 */
240
241/*
242 * Atomically swap in the new signal mask, and wait for a signal.
243 */
244long sys_sigsuspend(old_sigset_t mask)
245{
246 sigset_t blocked;
247 siginitset(&blocked, mask);
248 return sigsuspend(&blocked);
249}
250
251long sys_sigaction(int sig, struct old_sigaction __user *act,
252 struct old_sigaction __user *oact)
253{
254 struct k_sigaction new_ka, old_ka;
255 int ret;
256
257#ifdef CONFIG_PPC64
258 if (sig < 0)
259 sig = -sig;
260#endif
261
262 if (act) {
263 if (get_old_sigaction(&new_ka, act))
264 return -EFAULT;
265 }
266
267 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
268 if (!ret && oact) {
269 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
270 __put_user(to_user_ptr(old_ka.sa.sa_handler),
271 &oact->sa_handler) ||
272 __put_user(to_user_ptr(old_ka.sa.sa_restorer),
273 &oact->sa_restorer) ||
274 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
275 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
276 return -EFAULT;
277 }
278
279 return ret;
280}
281
282/*
283 * When we have signals to deliver, we set up on the
284 * user stack, going down from the original stack pointer:
285 * an ABI gap of 56 words
286 * an mcontext struct
287 * a sigcontext struct
288 * a gap of __SIGNAL_FRAMESIZE bytes
289 *
290 * Each of these things must be a multiple of 16 bytes in size. The following
291 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
292 *
293 */
294struct sigframe {
295 struct sigcontext sctx; /* the sigcontext */
296 struct mcontext mctx; /* all the register values */
297 /*
298 * Programs using the rs6000/xcoff abi can save up to 19 gp
299 * regs and 18 fp regs below sp before decrementing it.
300 */
301 int abigap[56];
302};
303
304/* We use the mc_pad field for the signal return trampoline. */
305#define tramp mc_pad
306
307/*
308 * When we have rt signals to deliver, we set up on the
309 * user stack, going down from the original stack pointer:
310 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
311 * a gap of __SIGNAL_FRAMESIZE+16 bytes
312 * (the +16 is to get the siginfo and ucontext in the same
313 * positions as in older kernels).
314 *
315 * Each of these things must be a multiple of 16 bytes in size.
316 *
317 */
318struct rt_sigframe {
319#ifdef CONFIG_PPC64
320 compat_siginfo_t info;
321#else
322 struct siginfo info;
323#endif
324 struct ucontext uc;
325 /*
326 * Programs using the rs6000/xcoff abi can save up to 19 gp
327 * regs and 18 fp regs below sp before decrementing it.
328 */
329 int abigap[56];
330};
331
332#ifdef CONFIG_VSX
333unsigned long copy_fpr_to_user(void __user *to,
334 struct task_struct *task)
335{
336 double buf[ELF_NFPREG];
337 int i;
338
339 /* save FPR copy to local buffer then write to the thread_struct */
340 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
341 buf[i] = task->thread.TS_FPR(i);
342 memcpy(&buf[i], &task->thread.fpscr, sizeof(double));
343 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
344}
345
346unsigned long copy_fpr_from_user(struct task_struct *task,
347 void __user *from)
348{
349 double buf[ELF_NFPREG];
350 int i;
351
352 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
353 return 1;
354 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
355 task->thread.TS_FPR(i) = buf[i];
356 memcpy(&task->thread.fpscr, &buf[i], sizeof(double));
357
358 return 0;
359}
360
361unsigned long copy_vsx_to_user(void __user *to,
362 struct task_struct *task)
363{
364 double buf[ELF_NVSRHALFREG];
365 int i;
366
367 /* save FPR copy to local buffer then write to the thread_struct */
368 for (i = 0; i < ELF_NVSRHALFREG; i++)
369 buf[i] = task->thread.fpr[i][TS_VSRLOWOFFSET];
370 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
371}
372
373unsigned long copy_vsx_from_user(struct task_struct *task,
374 void __user *from)
375{
376 double buf[ELF_NVSRHALFREG];
377 int i;
378
379 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
380 return 1;
381 for (i = 0; i < ELF_NVSRHALFREG ; i++)
382 task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
383 return 0;
384}
385#else
386inline unsigned long copy_fpr_to_user(void __user *to,
387 struct task_struct *task)
388{
389 return __copy_to_user(to, task->thread.fpr,
390 ELF_NFPREG * sizeof(double));
391}
392
393inline unsigned long copy_fpr_from_user(struct task_struct *task,
394 void __user *from)
395{
396 return __copy_from_user(task->thread.fpr, from,
397 ELF_NFPREG * sizeof(double));
398}
399#endif
400
401/*
402 * Save the current user registers on the user stack.
403 * We only save the altivec/spe registers if the process has used
404 * altivec/spe instructions at some point.
405 */
406static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
407 int sigret, int ctx_has_vsx_region)
408{
409 unsigned long msr = regs->msr;
410
411 /* Make sure floating point registers are stored in regs */
412 flush_fp_to_thread(current);
413
414 /* save general registers */
415 if (save_general_regs(regs, frame))
416 return 1;
417
418#ifdef CONFIG_ALTIVEC
419 /* save altivec registers */
420 if (current->thread.used_vr) {
421 flush_altivec_to_thread(current);
422 if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
423 ELF_NVRREG * sizeof(vector128)))
424 return 1;
425 /* set MSR_VEC in the saved MSR value to indicate that
426 frame->mc_vregs contains valid data */
427 msr |= MSR_VEC;
428 }
429 /* else assert((regs->msr & MSR_VEC) == 0) */
430
431 /* We always copy to/from vrsave, it's 0 if we don't have or don't
432 * use altivec. Since VSCR only contains 32 bits saved in the least
433 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
434 * most significant bits of that same vector. --BenH
435 */
436 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
437 return 1;
438#endif /* CONFIG_ALTIVEC */
439 if (copy_fpr_to_user(&frame->mc_fregs, current))
440 return 1;
441#ifdef CONFIG_VSX
442 /*
443 * Copy VSR 0-31 upper half from thread_struct to local
444 * buffer, then write that to userspace. Also set MSR_VSX in
445 * the saved MSR value to indicate that frame->mc_vregs
446 * contains valid data
447 */
448 if (current->thread.used_vsr && ctx_has_vsx_region) {
449 __giveup_vsx(current);
450 if (copy_vsx_to_user(&frame->mc_vsregs, current))
451 return 1;
452 msr |= MSR_VSX;
453 }
454#endif /* CONFIG_VSX */
455#ifdef CONFIG_SPE
456 /* save spe registers */
457 if (current->thread.used_spe) {
458 flush_spe_to_thread(current);
459 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
460 ELF_NEVRREG * sizeof(u32)))
461 return 1;
462 /* set MSR_SPE in the saved MSR value to indicate that
463 frame->mc_vregs contains valid data */
464 msr |= MSR_SPE;
465 }
466 /* else assert((regs->msr & MSR_SPE) == 0) */
467
468 /* We always copy to/from spefscr */
469 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
470 return 1;
471#endif /* CONFIG_SPE */
472
473 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
474 return 1;
475 if (sigret) {
476 /* Set up the sigreturn trampoline: li r0,sigret; sc */
477 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
478 || __put_user(0x44000002UL, &frame->tramp[1]))
479 return 1;
480 flush_icache_range((unsigned long) &frame->tramp[0],
481 (unsigned long) &frame->tramp[2]);
482 }
483
484 return 0;
485}
486
487/*
488 * Restore the current user register values from the user stack,
489 * (except for MSR).
490 */
491static long restore_user_regs(struct pt_regs *regs,
492 struct mcontext __user *sr, int sig)
493{
494 long err;
495 unsigned int save_r2 = 0;
496 unsigned long msr;
497#ifdef CONFIG_VSX
498 int i;
499#endif
500
501 /*
502 * restore general registers but not including MSR or SOFTE. Also
503 * take care of keeping r2 (TLS) intact if not a signal
504 */
505 if (!sig)
506 save_r2 = (unsigned int)regs->gpr[2];
507 err = restore_general_regs(regs, sr);
508 regs->trap = 0;
509 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
510 if (!sig)
511 regs->gpr[2] = (unsigned long) save_r2;
512 if (err)
513 return 1;
514
515 /* if doing signal return, restore the previous little-endian mode */
516 if (sig)
517 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
518
519 /*
520 * Do this before updating the thread state in
521 * current->thread.fpr/vr/evr. That way, if we get preempted
522 * and another task grabs the FPU/Altivec/SPE, it won't be
523 * tempted to save the current CPU state into the thread_struct
524 * and corrupt what we are writing there.
525 */
526 discard_lazy_cpu_state();
527
528#ifdef CONFIG_ALTIVEC
529 /*
530 * Force the process to reload the altivec registers from
531 * current->thread when it next does altivec instructions
532 */
533 regs->msr &= ~MSR_VEC;
534 if (msr & MSR_VEC) {
535 /* restore altivec registers from the stack */
536 if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
537 sizeof(sr->mc_vregs)))
538 return 1;
539 } else if (current->thread.used_vr)
540 memset(current->thread.vr, 0, ELF_NVRREG * sizeof(vector128));
541
542 /* Always get VRSAVE back */
543 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
544 return 1;
545#endif /* CONFIG_ALTIVEC */
546 if (copy_fpr_from_user(current, &sr->mc_fregs))
547 return 1;
548
549#ifdef CONFIG_VSX
550 /*
551 * Force the process to reload the VSX registers from
552 * current->thread when it next does VSX instruction.
553 */
554 regs->msr &= ~MSR_VSX;
555 if (msr & MSR_VSX) {
556 /*
557 * Restore altivec registers from the stack to a local
558 * buffer, then write this out to the thread_struct
559 */
560 if (copy_vsx_from_user(current, &sr->mc_vsregs))
561 return 1;
562 } else if (current->thread.used_vsr)
563 for (i = 0; i < 32 ; i++)
564 current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
565#endif /* CONFIG_VSX */
566 /*
567 * force the process to reload the FP registers from
568 * current->thread when it next does FP instructions
569 */
570 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
571
572#ifdef CONFIG_SPE
573 /* force the process to reload the spe registers from
574 current->thread when it next does spe instructions */
575 regs->msr &= ~MSR_SPE;
576 if (msr & MSR_SPE) {
577 /* restore spe registers from the stack */
578 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
579 ELF_NEVRREG * sizeof(u32)))
580 return 1;
581 } else if (current->thread.used_spe)
582 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
583
584 /* Always get SPEFSCR back */
585 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
586 return 1;
587#endif /* CONFIG_SPE */
588
589 return 0;
590}
591
592#ifdef CONFIG_PPC64
593long compat_sys_rt_sigaction(int sig, const struct sigaction32 __user *act,
594 struct sigaction32 __user *oact, size_t sigsetsize)
595{
596 struct k_sigaction new_ka, old_ka;
597 int ret;
598
599 /* XXX: Don't preclude handling different sized sigset_t's. */
600 if (sigsetsize != sizeof(compat_sigset_t))
601 return -EINVAL;
602
603 if (act) {
604 compat_uptr_t handler;
605
606 ret = get_user(handler, &act->sa_handler);
607 new_ka.sa.sa_handler = compat_ptr(handler);
608 ret |= get_sigset_t(&new_ka.sa.sa_mask, &act->sa_mask);
609 ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
610 if (ret)
611 return -EFAULT;
612 }
613
614 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
615 if (!ret && oact) {
616 ret = put_user(to_user_ptr(old_ka.sa.sa_handler), &oact->sa_handler);
617 ret |= put_sigset_t(&oact->sa_mask, &old_ka.sa.sa_mask);
618 ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
619 }
620 return ret;
621}
622
623/*
624 * Note: it is necessary to treat how as an unsigned int, with the
625 * corresponding cast to a signed int to insure that the proper
626 * conversion (sign extension) between the register representation
627 * of a signed int (msr in 32-bit mode) and the register representation
628 * of a signed int (msr in 64-bit mode) is performed.
629 */
630long compat_sys_rt_sigprocmask(u32 how, compat_sigset_t __user *set,
631 compat_sigset_t __user *oset, size_t sigsetsize)
632{
633 sigset_t s;
634 sigset_t __user *up;
635 int ret;
636 mm_segment_t old_fs = get_fs();
637
638 if (set) {
639 if (get_sigset_t(&s, set))
640 return -EFAULT;
641 }
642
643 set_fs(KERNEL_DS);
644 /* This is valid because of the set_fs() */
645 up = (sigset_t __user *) &s;
646 ret = sys_rt_sigprocmask((int)how, set ? up : NULL, oset ? up : NULL,
647 sigsetsize);
648 set_fs(old_fs);
649 if (ret)
650 return ret;
651 if (oset) {
652 if (put_sigset_t(oset, &s))
653 return -EFAULT;
654 }
655 return 0;
656}
657
658long compat_sys_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize)
659{
660 sigset_t s;
661 int ret;
662 mm_segment_t old_fs = get_fs();
663
664 set_fs(KERNEL_DS);
665 /* The __user pointer cast is valid because of the set_fs() */
666 ret = sys_rt_sigpending((sigset_t __user *) &s, sigsetsize);
667 set_fs(old_fs);
668 if (!ret) {
669 if (put_sigset_t(set, &s))
670 return -EFAULT;
671 }
672 return ret;
673}
674
675
676int copy_siginfo_to_user32(struct compat_siginfo __user *d, siginfo_t *s)
677{
678 int err;
679
680 if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
681 return -EFAULT;
682
683 /* If you change siginfo_t structure, please be sure
684 * this code is fixed accordingly.
685 * It should never copy any pad contained in the structure
686 * to avoid security leaks, but must copy the generic
687 * 3 ints plus the relevant union member.
688 * This routine must convert siginfo from 64bit to 32bit as well
689 * at the same time.
690 */
691 err = __put_user(s->si_signo, &d->si_signo);
692 err |= __put_user(s->si_errno, &d->si_errno);
693 err |= __put_user((short)s->si_code, &d->si_code);
694 if (s->si_code < 0)
695 err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
696 SI_PAD_SIZE32);
697 else switch(s->si_code >> 16) {
698 case __SI_CHLD >> 16:
699 err |= __put_user(s->si_pid, &d->si_pid);
700 err |= __put_user(s->si_uid, &d->si_uid);
701 err |= __put_user(s->si_utime, &d->si_utime);
702 err |= __put_user(s->si_stime, &d->si_stime);
703 err |= __put_user(s->si_status, &d->si_status);
704 break;
705 case __SI_FAULT >> 16:
706 err |= __put_user((unsigned int)(unsigned long)s->si_addr,
707 &d->si_addr);
708 break;
709 case __SI_POLL >> 16:
710 err |= __put_user(s->si_band, &d->si_band);
711 err |= __put_user(s->si_fd, &d->si_fd);
712 break;
713 case __SI_TIMER >> 16:
714 err |= __put_user(s->si_tid, &d->si_tid);
715 err |= __put_user(s->si_overrun, &d->si_overrun);
716 err |= __put_user(s->si_int, &d->si_int);
717 break;
718 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
719 case __SI_MESGQ >> 16:
720 err |= __put_user(s->si_int, &d->si_int);
721 /* fallthrough */
722 case __SI_KILL >> 16:
723 default:
724 err |= __put_user(s->si_pid, &d->si_pid);
725 err |= __put_user(s->si_uid, &d->si_uid);
726 break;
727 }
728 return err;
729}
730
731#define copy_siginfo_to_user copy_siginfo_to_user32
732
733int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
734{
735 memset(to, 0, sizeof *to);
736
737 if (copy_from_user(to, from, 3*sizeof(int)) ||
738 copy_from_user(to->_sifields._pad,
739 from->_sifields._pad, SI_PAD_SIZE32))
740 return -EFAULT;
741
742 return 0;
743}
744
745/*
746 * Note: it is necessary to treat pid and sig as unsigned ints, with the
747 * corresponding cast to a signed int to insure that the proper conversion
748 * (sign extension) between the register representation of a signed int
749 * (msr in 32-bit mode) and the register representation of a signed int
750 * (msr in 64-bit mode) is performed.
751 */
752long compat_sys_rt_sigqueueinfo(u32 pid, u32 sig, compat_siginfo_t __user *uinfo)
753{
754 siginfo_t info;
755 int ret;
756 mm_segment_t old_fs = get_fs();
757
758 ret = copy_siginfo_from_user32(&info, uinfo);
759 if (unlikely(ret))
760 return ret;
761
762 set_fs (KERNEL_DS);
763 /* The __user pointer cast is valid becasuse of the set_fs() */
764 ret = sys_rt_sigqueueinfo((int)pid, (int)sig, (siginfo_t __user *) &info);
765 set_fs (old_fs);
766 return ret;
767}
768/*
769 * Start Alternate signal stack support
770 *
771 * System Calls
772 * sigaltatck compat_sys_sigaltstack
773 */
774
775int compat_sys_sigaltstack(u32 __new, u32 __old, int r5,
776 int r6, int r7, int r8, struct pt_regs *regs)
777{
778 stack_32_t __user * newstack = compat_ptr(__new);
779 stack_32_t __user * oldstack = compat_ptr(__old);
780 stack_t uss, uoss;
781 int ret;
782 mm_segment_t old_fs;
783 unsigned long sp;
784 compat_uptr_t ss_sp;
785
786 /*
787 * set sp to the user stack on entry to the system call
788 * the system call router sets R9 to the saved registers
789 */
790 sp = regs->gpr[1];
791
792 /* Put new stack info in local 64 bit stack struct */
793 if (newstack) {
794 if (get_user(ss_sp, &newstack->ss_sp) ||
795 __get_user(uss.ss_flags, &newstack->ss_flags) ||
796 __get_user(uss.ss_size, &newstack->ss_size))
797 return -EFAULT;
798 uss.ss_sp = compat_ptr(ss_sp);
799 }
800
801 old_fs = get_fs();
802 set_fs(KERNEL_DS);
803 /* The __user pointer casts are valid because of the set_fs() */
804 ret = do_sigaltstack(
805 newstack ? (stack_t __user *) &uss : NULL,
806 oldstack ? (stack_t __user *) &uoss : NULL,
807 sp);
808 set_fs(old_fs);
809 /* Copy the stack information to the user output buffer */
810 if (!ret && oldstack &&
811 (put_user(ptr_to_compat(uoss.ss_sp), &oldstack->ss_sp) ||
812 __put_user(uoss.ss_flags, &oldstack->ss_flags) ||
813 __put_user(uoss.ss_size, &oldstack->ss_size)))
814 return -EFAULT;
815 return ret;
816}
817#endif /* CONFIG_PPC64 */
818
819/*
820 * Set up a signal frame for a "real-time" signal handler
821 * (one which gets siginfo).
822 */
823int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
824 siginfo_t *info, sigset_t *oldset,
825 struct pt_regs *regs)
826{
827 struct rt_sigframe __user *rt_sf;
828 struct mcontext __user *frame;
829 void __user *addr;
830 unsigned long newsp = 0;
831
832 /* Set up Signal Frame */
833 /* Put a Real Time Context onto stack */
834 rt_sf = get_sigframe(ka, regs, sizeof(*rt_sf), 1);
835 addr = rt_sf;
836 if (unlikely(rt_sf == NULL))
837 goto badframe;
838
839 /* Put the siginfo & fill in most of the ucontext */
840 if (copy_siginfo_to_user(&rt_sf->info, info)
841 || __put_user(0, &rt_sf->uc.uc_flags)
842 || __put_user(0, &rt_sf->uc.uc_link)
843 || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
844 || __put_user(sas_ss_flags(regs->gpr[1]),
845 &rt_sf->uc.uc_stack.ss_flags)
846 || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
847 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
848 &rt_sf->uc.uc_regs)
849 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
850 goto badframe;
851
852 /* Save user registers on the stack */
853 frame = &rt_sf->uc.uc_mcontext;
854 addr = frame;
855 if (vdso32_rt_sigtramp && current->mm->context.vdso_base) {
856 if (save_user_regs(regs, frame, 0, 1))
857 goto badframe;
858 regs->link = current->mm->context.vdso_base + vdso32_rt_sigtramp;
859 } else {
860 if (save_user_regs(regs, frame, __NR_rt_sigreturn, 1))
861 goto badframe;
862 regs->link = (unsigned long) frame->tramp;
863 }
864
865 current->thread.fpscr.val = 0; /* turn off all fp exceptions */
866
867 /* create a stack frame for the caller of the handler */
868 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
869 addr = (void __user *)regs->gpr[1];
870 if (put_user(regs->gpr[1], (u32 __user *)newsp))
871 goto badframe;
872
873 /* Fill registers for signal handler */
874 regs->gpr[1] = newsp;
875 regs->gpr[3] = sig;
876 regs->gpr[4] = (unsigned long) &rt_sf->info;
877 regs->gpr[5] = (unsigned long) &rt_sf->uc;
878 regs->gpr[6] = (unsigned long) rt_sf;
879 regs->nip = (unsigned long) ka->sa.sa_handler;
880 /* enter the signal handler in big-endian mode */
881 regs->msr &= ~MSR_LE;
882 return 1;
883
884badframe:
885#ifdef DEBUG_SIG
886 printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
887 regs, frame, newsp);
888#endif
889 if (show_unhandled_signals)
890 printk_ratelimited(KERN_INFO
891 "%s[%d]: bad frame in handle_rt_signal32: "
892 "%p nip %08lx lr %08lx\n",
893 current->comm, current->pid,
894 addr, regs->nip, regs->link);
895
896 force_sigsegv(sig, current);
897 return 0;
898}
899
900static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
901{
902 sigset_t set;
903 struct mcontext __user *mcp;
904
905 if (get_sigset_t(&set, &ucp->uc_sigmask))
906 return -EFAULT;
907#ifdef CONFIG_PPC64
908 {
909 u32 cmcp;
910
911 if (__get_user(cmcp, &ucp->uc_regs))
912 return -EFAULT;
913 mcp = (struct mcontext __user *)(u64)cmcp;
914 /* no need to check access_ok(mcp), since mcp < 4GB */
915 }
916#else
917 if (__get_user(mcp, &ucp->uc_regs))
918 return -EFAULT;
919 if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp)))
920 return -EFAULT;
921#endif
922 set_current_blocked(&set);
923 if (restore_user_regs(regs, mcp, sig))
924 return -EFAULT;
925
926 return 0;
927}
928
929long sys_swapcontext(struct ucontext __user *old_ctx,
930 struct ucontext __user *new_ctx,
931 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
932{
933 unsigned char tmp;
934 int ctx_has_vsx_region = 0;
935
936#ifdef CONFIG_PPC64
937 unsigned long new_msr = 0;
938
939 if (new_ctx) {
940 struct mcontext __user *mcp;
941 u32 cmcp;
942
943 /*
944 * Get pointer to the real mcontext. No need for
945 * access_ok since we are dealing with compat
946 * pointers.
947 */
948 if (__get_user(cmcp, &new_ctx->uc_regs))
949 return -EFAULT;
950 mcp = (struct mcontext __user *)(u64)cmcp;
951 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
952 return -EFAULT;
953 }
954 /*
955 * Check that the context is not smaller than the original
956 * size (with VMX but without VSX)
957 */
958 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
959 return -EINVAL;
960 /*
961 * If the new context state sets the MSR VSX bits but
962 * it doesn't provide VSX state.
963 */
964 if ((ctx_size < sizeof(struct ucontext)) &&
965 (new_msr & MSR_VSX))
966 return -EINVAL;
967 /* Does the context have enough room to store VSX data? */
968 if (ctx_size >= sizeof(struct ucontext))
969 ctx_has_vsx_region = 1;
970#else
971 /* Context size is for future use. Right now, we only make sure
972 * we are passed something we understand
973 */
974 if (ctx_size < sizeof(struct ucontext))
975 return -EINVAL;
976#endif
977 if (old_ctx != NULL) {
978 struct mcontext __user *mctx;
979
980 /*
981 * old_ctx might not be 16-byte aligned, in which
982 * case old_ctx->uc_mcontext won't be either.
983 * Because we have the old_ctx->uc_pad2 field
984 * before old_ctx->uc_mcontext, we need to round down
985 * from &old_ctx->uc_mcontext to a 16-byte boundary.
986 */
987 mctx = (struct mcontext __user *)
988 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
989 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
990 || save_user_regs(regs, mctx, 0, ctx_has_vsx_region)
991 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
992 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
993 return -EFAULT;
994 }
995 if (new_ctx == NULL)
996 return 0;
997 if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
998 || __get_user(tmp, (u8 __user *) new_ctx)
999 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
1000 return -EFAULT;
1001
1002 /*
1003 * If we get a fault copying the context into the kernel's
1004 * image of the user's registers, we can't just return -EFAULT
1005 * because the user's registers will be corrupted. For instance
1006 * the NIP value may have been updated but not some of the
1007 * other registers. Given that we have done the access_ok
1008 * and successfully read the first and last bytes of the region
1009 * above, this should only happen in an out-of-memory situation
1010 * or if another thread unmaps the region containing the context.
1011 * We kill the task with a SIGSEGV in this situation.
1012 */
1013 if (do_setcontext(new_ctx, regs, 0))
1014 do_exit(SIGSEGV);
1015
1016 set_thread_flag(TIF_RESTOREALL);
1017 return 0;
1018}
1019
1020long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1021 struct pt_regs *regs)
1022{
1023 struct rt_sigframe __user *rt_sf;
1024
1025 /* Always make any pending restarted system calls return -EINTR */
1026 current_thread_info()->restart_block.fn = do_no_restart_syscall;
1027
1028 rt_sf = (struct rt_sigframe __user *)
1029 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1030 if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
1031 goto bad;
1032 if (do_setcontext(&rt_sf->uc, regs, 1))
1033 goto bad;
1034
1035 /*
1036 * It's not clear whether or why it is desirable to save the
1037 * sigaltstack setting on signal delivery and restore it on
1038 * signal return. But other architectures do this and we have
1039 * always done it up until now so it is probably better not to
1040 * change it. -- paulus
1041 */
1042#ifdef CONFIG_PPC64
1043 /*
1044 * We use the compat_sys_ version that does the 32/64 bits conversion
1045 * and takes userland pointer directly. What about error checking ?
1046 * nobody does any...
1047 */
1048 compat_sys_sigaltstack((u32)(u64)&rt_sf->uc.uc_stack, 0, 0, 0, 0, 0, regs);
1049#else
1050 do_sigaltstack(&rt_sf->uc.uc_stack, NULL, regs->gpr[1]);
1051#endif
1052 set_thread_flag(TIF_RESTOREALL);
1053 return 0;
1054
1055 bad:
1056 if (show_unhandled_signals)
1057 printk_ratelimited(KERN_INFO
1058 "%s[%d]: bad frame in sys_rt_sigreturn: "
1059 "%p nip %08lx lr %08lx\n",
1060 current->comm, current->pid,
1061 rt_sf, regs->nip, regs->link);
1062
1063 force_sig(SIGSEGV, current);
1064 return 0;
1065}
1066
1067#ifdef CONFIG_PPC32
1068int sys_debug_setcontext(struct ucontext __user *ctx,
1069 int ndbg, struct sig_dbg_op __user *dbg,
1070 int r6, int r7, int r8,
1071 struct pt_regs *regs)
1072{
1073 struct sig_dbg_op op;
1074 int i;
1075 unsigned char tmp;
1076 unsigned long new_msr = regs->msr;
1077#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1078 unsigned long new_dbcr0 = current->thread.dbcr0;
1079#endif
1080
1081 for (i=0; i<ndbg; i++) {
1082 if (copy_from_user(&op, dbg + i, sizeof(op)))
1083 return -EFAULT;
1084 switch (op.dbg_type) {
1085 case SIG_DBG_SINGLE_STEPPING:
1086#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1087 if (op.dbg_value) {
1088 new_msr |= MSR_DE;
1089 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1090 } else {
1091 new_dbcr0 &= ~DBCR0_IC;
1092 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1093 current->thread.dbcr1)) {
1094 new_msr &= ~MSR_DE;
1095 new_dbcr0 &= ~DBCR0_IDM;
1096 }
1097 }
1098#else
1099 if (op.dbg_value)
1100 new_msr |= MSR_SE;
1101 else
1102 new_msr &= ~MSR_SE;
1103#endif
1104 break;
1105 case SIG_DBG_BRANCH_TRACING:
1106#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1107 return -EINVAL;
1108#else
1109 if (op.dbg_value)
1110 new_msr |= MSR_BE;
1111 else
1112 new_msr &= ~MSR_BE;
1113#endif
1114 break;
1115
1116 default:
1117 return -EINVAL;
1118 }
1119 }
1120
1121 /* We wait until here to actually install the values in the
1122 registers so if we fail in the above loop, it will not
1123 affect the contents of these registers. After this point,
1124 failure is a problem, anyway, and it's very unlikely unless
1125 the user is really doing something wrong. */
1126 regs->msr = new_msr;
1127#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1128 current->thread.dbcr0 = new_dbcr0;
1129#endif
1130
1131 if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx))
1132 || __get_user(tmp, (u8 __user *) ctx)
1133 || __get_user(tmp, (u8 __user *) (ctx + 1) - 1))
1134 return -EFAULT;
1135
1136 /*
1137 * If we get a fault copying the context into the kernel's
1138 * image of the user's registers, we can't just return -EFAULT
1139 * because the user's registers will be corrupted. For instance
1140 * the NIP value may have been updated but not some of the
1141 * other registers. Given that we have done the access_ok
1142 * and successfully read the first and last bytes of the region
1143 * above, this should only happen in an out-of-memory situation
1144 * or if another thread unmaps the region containing the context.
1145 * We kill the task with a SIGSEGV in this situation.
1146 */
1147 if (do_setcontext(ctx, regs, 1)) {
1148 if (show_unhandled_signals)
1149 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1150 "sys_debug_setcontext: %p nip %08lx "
1151 "lr %08lx\n",
1152 current->comm, current->pid,
1153 ctx, regs->nip, regs->link);
1154
1155 force_sig(SIGSEGV, current);
1156 goto out;
1157 }
1158
1159 /*
1160 * It's not clear whether or why it is desirable to save the
1161 * sigaltstack setting on signal delivery and restore it on
1162 * signal return. But other architectures do this and we have
1163 * always done it up until now so it is probably better not to
1164 * change it. -- paulus
1165 */
1166 do_sigaltstack(&ctx->uc_stack, NULL, regs->gpr[1]);
1167
1168 set_thread_flag(TIF_RESTOREALL);
1169 out:
1170 return 0;
1171}
1172#endif
1173
1174/*
1175 * OK, we're invoking a handler
1176 */
1177int handle_signal32(unsigned long sig, struct k_sigaction *ka,
1178 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
1179{
1180 struct sigcontext __user *sc;
1181 struct sigframe __user *frame;
1182 unsigned long newsp = 0;
1183
1184 /* Set up Signal Frame */
1185 frame = get_sigframe(ka, regs, sizeof(*frame), 1);
1186 if (unlikely(frame == NULL))
1187 goto badframe;
1188 sc = (struct sigcontext __user *) &frame->sctx;
1189
1190#if _NSIG != 64
1191#error "Please adjust handle_signal()"
1192#endif
1193 if (__put_user(to_user_ptr(ka->sa.sa_handler), &sc->handler)
1194 || __put_user(oldset->sig[0], &sc->oldmask)
1195#ifdef CONFIG_PPC64
1196 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1197#else
1198 || __put_user(oldset->sig[1], &sc->_unused[3])
1199#endif
1200 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1201 || __put_user(sig, &sc->signal))
1202 goto badframe;
1203
1204 if (vdso32_sigtramp && current->mm->context.vdso_base) {
1205 if (save_user_regs(regs, &frame->mctx, 0, 1))
1206 goto badframe;
1207 regs->link = current->mm->context.vdso_base + vdso32_sigtramp;
1208 } else {
1209 if (save_user_regs(regs, &frame->mctx, __NR_sigreturn, 1))
1210 goto badframe;
1211 regs->link = (unsigned long) frame->mctx.tramp;
1212 }
1213
1214 current->thread.fpscr.val = 0; /* turn off all fp exceptions */
1215
1216 /* create a stack frame for the caller of the handler */
1217 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1218 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1219 goto badframe;
1220
1221 regs->gpr[1] = newsp;
1222 regs->gpr[3] = sig;
1223 regs->gpr[4] = (unsigned long) sc;
1224 regs->nip = (unsigned long) ka->sa.sa_handler;
1225 /* enter the signal handler in big-endian mode */
1226 regs->msr &= ~MSR_LE;
1227
1228 return 1;
1229
1230badframe:
1231#ifdef DEBUG_SIG
1232 printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
1233 regs, frame, newsp);
1234#endif
1235 if (show_unhandled_signals)
1236 printk_ratelimited(KERN_INFO
1237 "%s[%d]: bad frame in handle_signal32: "
1238 "%p nip %08lx lr %08lx\n",
1239 current->comm, current->pid,
1240 frame, regs->nip, regs->link);
1241
1242 force_sigsegv(sig, current);
1243 return 0;
1244}
1245
1246/*
1247 * Do a signal return; undo the signal stack.
1248 */
1249long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1250 struct pt_regs *regs)
1251{
1252 struct sigcontext __user *sc;
1253 struct sigcontext sigctx;
1254 struct mcontext __user *sr;
1255 void __user *addr;
1256 sigset_t set;
1257
1258 /* Always make any pending restarted system calls return -EINTR */
1259 current_thread_info()->restart_block.fn = do_no_restart_syscall;
1260
1261 sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1262 addr = sc;
1263 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1264 goto badframe;
1265
1266#ifdef CONFIG_PPC64
1267 /*
1268 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1269 * unused part of the signal stackframe
1270 */
1271 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1272#else
1273 set.sig[0] = sigctx.oldmask;
1274 set.sig[1] = sigctx._unused[3];
1275#endif
1276 set_current_blocked(&set);
1277
1278 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1279 addr = sr;
1280 if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
1281 || restore_user_regs(regs, sr, 1))
1282 goto badframe;
1283
1284 set_thread_flag(TIF_RESTOREALL);
1285 return 0;
1286
1287badframe:
1288 if (show_unhandled_signals)
1289 printk_ratelimited(KERN_INFO
1290 "%s[%d]: bad frame in sys_sigreturn: "
1291 "%p nip %08lx lr %08lx\n",
1292 current->comm, current->pid,
1293 addr, regs->nip, regs->link);
1294
1295 force_sig(SIGSEGV, current);
1296 return 0;
1297}