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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// 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#include <asm/pgtable.h>
51#endif
52
53#include "signal.h"
54
55
56#ifdef CONFIG_PPC64
57#define old_sigaction old_sigaction32
58#define sigcontext sigcontext32
59#define mcontext mcontext32
60#define ucontext ucontext32
61
62#define __save_altstack __compat_save_altstack
63
64/*
65 * Userspace code may pass a ucontext which doesn't include VSX added
66 * at the end. We need to check for this case.
67 */
68#define UCONTEXTSIZEWITHOUTVSX \
69 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
70
71/*
72 * Returning 0 means we return to userspace via
73 * ret_from_except and thus restore all user
74 * registers from *regs. This is what we need
75 * to do when a signal has been delivered.
76 */
77
78#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
79#undef __SIGNAL_FRAMESIZE
80#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
81#undef ELF_NVRREG
82#define ELF_NVRREG ELF_NVRREG32
83
84/*
85 * Functions for flipping sigsets (thanks to brain dead generic
86 * implementation that makes things simple for little endian only)
87 */
88static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
89{
90 return put_compat_sigset(uset, set, sizeof(*uset));
91}
92
93static inline int get_sigset_t(sigset_t *set,
94 const compat_sigset_t __user *uset)
95{
96 return get_compat_sigset(set, uset);
97}
98
99#define to_user_ptr(p) ptr_to_compat(p)
100#define from_user_ptr(p) compat_ptr(p)
101
102static inline int save_general_regs(struct pt_regs *regs,
103 struct mcontext __user *frame)
104{
105 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
106 int i;
107 /* Force usr to alway see softe as 1 (interrupts enabled) */
108 elf_greg_t64 softe = 0x1;
109
110 WARN_ON(!FULL_REGS(regs));
111
112 for (i = 0; i <= PT_RESULT; i ++) {
113 if (i == 14 && !FULL_REGS(regs))
114 i = 32;
115 if ( i == PT_SOFTE) {
116 if(__put_user((unsigned int)softe, &frame->mc_gregs[i]))
117 return -EFAULT;
118 else
119 continue;
120 }
121 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
122 return -EFAULT;
123 }
124 return 0;
125}
126
127static inline int restore_general_regs(struct pt_regs *regs,
128 struct mcontext __user *sr)
129{
130 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
131 int i;
132
133 for (i = 0; i <= PT_RESULT; i++) {
134 if ((i == PT_MSR) || (i == PT_SOFTE))
135 continue;
136 if (__get_user(gregs[i], &sr->mc_gregs[i]))
137 return -EFAULT;
138 }
139 return 0;
140}
141
142#else /* CONFIG_PPC64 */
143
144#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
145
146static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
147{
148 return copy_to_user(uset, set, sizeof(*uset));
149}
150
151static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
152{
153 return copy_from_user(set, uset, sizeof(*uset));
154}
155
156#define to_user_ptr(p) ((unsigned long)(p))
157#define from_user_ptr(p) ((void __user *)(p))
158
159static inline int save_general_regs(struct pt_regs *regs,
160 struct mcontext __user *frame)
161{
162 WARN_ON(!FULL_REGS(regs));
163 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
164}
165
166static inline int restore_general_regs(struct pt_regs *regs,
167 struct mcontext __user *sr)
168{
169 /* copy up to but not including MSR */
170 if (__copy_from_user(regs, &sr->mc_gregs,
171 PT_MSR * sizeof(elf_greg_t)))
172 return -EFAULT;
173 /* copy from orig_r3 (the word after the MSR) up to the end */
174 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
175 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
176 return -EFAULT;
177 return 0;
178}
179#endif
180
181/*
182 * When we have signals to deliver, we set up on the
183 * user stack, going down from the original stack pointer:
184 * an ABI gap of 56 words
185 * an mcontext struct
186 * a sigcontext struct
187 * a gap of __SIGNAL_FRAMESIZE bytes
188 *
189 * Each of these things must be a multiple of 16 bytes in size. The following
190 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
191 *
192 */
193struct sigframe {
194 struct sigcontext sctx; /* the sigcontext */
195 struct mcontext mctx; /* all the register values */
196#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
197 struct sigcontext sctx_transact;
198 struct mcontext mctx_transact;
199#endif
200 /*
201 * Programs using the rs6000/xcoff abi can save up to 19 gp
202 * regs and 18 fp regs below sp before decrementing it.
203 */
204 int abigap[56];
205};
206
207/* We use the mc_pad field for the signal return trampoline. */
208#define tramp mc_pad
209
210/*
211 * When we have rt signals to deliver, we set up on the
212 * user stack, going down from the original stack pointer:
213 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
214 * a gap of __SIGNAL_FRAMESIZE+16 bytes
215 * (the +16 is to get the siginfo and ucontext in the same
216 * positions as in older kernels).
217 *
218 * Each of these things must be a multiple of 16 bytes in size.
219 *
220 */
221struct rt_sigframe {
222#ifdef CONFIG_PPC64
223 compat_siginfo_t info;
224#else
225 struct siginfo info;
226#endif
227 struct ucontext uc;
228#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
229 struct ucontext uc_transact;
230#endif
231 /*
232 * Programs using the rs6000/xcoff abi can save up to 19 gp
233 * regs and 18 fp regs below sp before decrementing it.
234 */
235 int abigap[56];
236};
237
238#ifdef CONFIG_VSX
239unsigned long copy_fpr_to_user(void __user *to,
240 struct task_struct *task)
241{
242 u64 buf[ELF_NFPREG];
243 int i;
244
245 /* save FPR copy to local buffer then write to the thread_struct */
246 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
247 buf[i] = task->thread.TS_FPR(i);
248 buf[i] = task->thread.fp_state.fpscr;
249 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
250}
251
252unsigned long copy_fpr_from_user(struct task_struct *task,
253 void __user *from)
254{
255 u64 buf[ELF_NFPREG];
256 int i;
257
258 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
259 return 1;
260 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
261 task->thread.TS_FPR(i) = buf[i];
262 task->thread.fp_state.fpscr = buf[i];
263
264 return 0;
265}
266
267unsigned long copy_vsx_to_user(void __user *to,
268 struct task_struct *task)
269{
270 u64 buf[ELF_NVSRHALFREG];
271 int i;
272
273 /* save FPR copy to local buffer then write to the thread_struct */
274 for (i = 0; i < ELF_NVSRHALFREG; i++)
275 buf[i] = task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
276 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
277}
278
279unsigned long copy_vsx_from_user(struct task_struct *task,
280 void __user *from)
281{
282 u64 buf[ELF_NVSRHALFREG];
283 int i;
284
285 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
286 return 1;
287 for (i = 0; i < ELF_NVSRHALFREG ; i++)
288 task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
289 return 0;
290}
291
292#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
293unsigned long copy_ckfpr_to_user(void __user *to,
294 struct task_struct *task)
295{
296 u64 buf[ELF_NFPREG];
297 int i;
298
299 /* save FPR copy to local buffer then write to the thread_struct */
300 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
301 buf[i] = task->thread.TS_CKFPR(i);
302 buf[i] = task->thread.ckfp_state.fpscr;
303 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
304}
305
306unsigned long copy_ckfpr_from_user(struct task_struct *task,
307 void __user *from)
308{
309 u64 buf[ELF_NFPREG];
310 int i;
311
312 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
313 return 1;
314 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
315 task->thread.TS_CKFPR(i) = buf[i];
316 task->thread.ckfp_state.fpscr = buf[i];
317
318 return 0;
319}
320
321unsigned long copy_ckvsx_to_user(void __user *to,
322 struct task_struct *task)
323{
324 u64 buf[ELF_NVSRHALFREG];
325 int i;
326
327 /* save FPR copy to local buffer then write to the thread_struct */
328 for (i = 0; i < ELF_NVSRHALFREG; i++)
329 buf[i] = task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET];
330 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
331}
332
333unsigned long copy_ckvsx_from_user(struct task_struct *task,
334 void __user *from)
335{
336 u64 buf[ELF_NVSRHALFREG];
337 int i;
338
339 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
340 return 1;
341 for (i = 0; i < ELF_NVSRHALFREG ; i++)
342 task->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
343 return 0;
344}
345#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
346#else
347inline unsigned long copy_fpr_to_user(void __user *to,
348 struct task_struct *task)
349{
350 return __copy_to_user(to, task->thread.fp_state.fpr,
351 ELF_NFPREG * sizeof(double));
352}
353
354inline unsigned long copy_fpr_from_user(struct task_struct *task,
355 void __user *from)
356{
357 return __copy_from_user(task->thread.fp_state.fpr, from,
358 ELF_NFPREG * sizeof(double));
359}
360
361#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
362inline unsigned long copy_ckfpr_to_user(void __user *to,
363 struct task_struct *task)
364{
365 return __copy_to_user(to, task->thread.ckfp_state.fpr,
366 ELF_NFPREG * sizeof(double));
367}
368
369inline unsigned long copy_ckfpr_from_user(struct task_struct *task,
370 void __user *from)
371{
372 return __copy_from_user(task->thread.ckfp_state.fpr, from,
373 ELF_NFPREG * sizeof(double));
374}
375#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
376#endif
377
378/*
379 * Save the current user registers on the user stack.
380 * We only save the altivec/spe registers if the process has used
381 * altivec/spe instructions at some point.
382 */
383static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
384 struct mcontext __user *tm_frame, int sigret,
385 int ctx_has_vsx_region)
386{
387 unsigned long msr = regs->msr;
388
389 /* Make sure floating point registers are stored in regs */
390 flush_fp_to_thread(current);
391
392 /* save general registers */
393 if (save_general_regs(regs, frame))
394 return 1;
395
396#ifdef CONFIG_ALTIVEC
397 /* save altivec registers */
398 if (current->thread.used_vr) {
399 flush_altivec_to_thread(current);
400 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
401 ELF_NVRREG * sizeof(vector128)))
402 return 1;
403 /* set MSR_VEC in the saved MSR value to indicate that
404 frame->mc_vregs contains valid data */
405 msr |= MSR_VEC;
406 }
407 /* else assert((regs->msr & MSR_VEC) == 0) */
408
409 /* We always copy to/from vrsave, it's 0 if we don't have or don't
410 * use altivec. Since VSCR only contains 32 bits saved in the least
411 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
412 * most significant bits of that same vector. --BenH
413 * Note that the current VRSAVE value is in the SPR at this point.
414 */
415 if (cpu_has_feature(CPU_FTR_ALTIVEC))
416 current->thread.vrsave = mfspr(SPRN_VRSAVE);
417 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
418 return 1;
419#endif /* CONFIG_ALTIVEC */
420 if (copy_fpr_to_user(&frame->mc_fregs, current))
421 return 1;
422
423 /*
424 * Clear the MSR VSX bit to indicate there is no valid state attached
425 * to this context, except in the specific case below where we set it.
426 */
427 msr &= ~MSR_VSX;
428#ifdef CONFIG_VSX
429 /*
430 * Copy VSR 0-31 upper half from thread_struct to local
431 * buffer, then write that to userspace. Also set MSR_VSX in
432 * the saved MSR value to indicate that frame->mc_vregs
433 * contains valid data
434 */
435 if (current->thread.used_vsr && ctx_has_vsx_region) {
436 flush_vsx_to_thread(current);
437 if (copy_vsx_to_user(&frame->mc_vsregs, current))
438 return 1;
439 msr |= MSR_VSX;
440 }
441#endif /* CONFIG_VSX */
442#ifdef CONFIG_SPE
443 /* save spe registers */
444 if (current->thread.used_spe) {
445 flush_spe_to_thread(current);
446 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
447 ELF_NEVRREG * sizeof(u32)))
448 return 1;
449 /* set MSR_SPE in the saved MSR value to indicate that
450 frame->mc_vregs contains valid data */
451 msr |= MSR_SPE;
452 }
453 /* else assert((regs->msr & MSR_SPE) == 0) */
454
455 /* We always copy to/from spefscr */
456 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
457 return 1;
458#endif /* CONFIG_SPE */
459
460 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
461 return 1;
462 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
463 * can check it on the restore to see if TM is active
464 */
465 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
466 return 1;
467
468 if (sigret) {
469 /* Set up the sigreturn trampoline: li 0,sigret; sc */
470 if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
471 || __put_user(PPC_INST_SC, &frame->tramp[1]))
472 return 1;
473 flush_icache_range((unsigned long) &frame->tramp[0],
474 (unsigned long) &frame->tramp[2]);
475 }
476
477 return 0;
478}
479
480#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
481/*
482 * Save the current user registers on the user stack.
483 * We only save the altivec/spe registers if the process has used
484 * altivec/spe instructions at some point.
485 * We also save the transactional registers to a second ucontext in the
486 * frame.
487 *
488 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
489 */
490static int save_tm_user_regs(struct pt_regs *regs,
491 struct mcontext __user *frame,
492 struct mcontext __user *tm_frame, int sigret)
493{
494 unsigned long msr = regs->msr;
495
496 WARN_ON(tm_suspend_disabled);
497
498 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
499 * just indicates to userland that we were doing a transaction, but we
500 * don't want to return in transactional state. This also ensures
501 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
502 */
503 regs->msr &= ~MSR_TS_MASK;
504
505 /* Save both sets of general registers */
506 if (save_general_regs(¤t->thread.ckpt_regs, frame)
507 || save_general_regs(regs, tm_frame))
508 return 1;
509
510 /* Stash the top half of the 64bit MSR into the 32bit MSR word
511 * of the transactional mcontext. This way we have a backward-compatible
512 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
513 * also look at what type of transaction (T or S) was active at the
514 * time of the signal.
515 */
516 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
517 return 1;
518
519#ifdef CONFIG_ALTIVEC
520 /* save altivec registers */
521 if (current->thread.used_vr) {
522 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
523 ELF_NVRREG * sizeof(vector128)))
524 return 1;
525 if (msr & MSR_VEC) {
526 if (__copy_to_user(&tm_frame->mc_vregs,
527 ¤t->thread.vr_state,
528 ELF_NVRREG * sizeof(vector128)))
529 return 1;
530 } else {
531 if (__copy_to_user(&tm_frame->mc_vregs,
532 ¤t->thread.ckvr_state,
533 ELF_NVRREG * sizeof(vector128)))
534 return 1;
535 }
536
537 /* set MSR_VEC in the saved MSR value to indicate that
538 * frame->mc_vregs contains valid data
539 */
540 msr |= MSR_VEC;
541 }
542
543 /* We always copy to/from vrsave, it's 0 if we don't have or don't
544 * use altivec. Since VSCR only contains 32 bits saved in the least
545 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
546 * most significant bits of that same vector. --BenH
547 */
548 if (cpu_has_feature(CPU_FTR_ALTIVEC))
549 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
550 if (__put_user(current->thread.ckvrsave,
551 (u32 __user *)&frame->mc_vregs[32]))
552 return 1;
553 if (msr & MSR_VEC) {
554 if (__put_user(current->thread.vrsave,
555 (u32 __user *)&tm_frame->mc_vregs[32]))
556 return 1;
557 } else {
558 if (__put_user(current->thread.ckvrsave,
559 (u32 __user *)&tm_frame->mc_vregs[32]))
560 return 1;
561 }
562#endif /* CONFIG_ALTIVEC */
563
564 if (copy_ckfpr_to_user(&frame->mc_fregs, current))
565 return 1;
566 if (msr & MSR_FP) {
567 if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
568 return 1;
569 } else {
570 if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
571 return 1;
572 }
573
574#ifdef CONFIG_VSX
575 /*
576 * Copy VSR 0-31 upper half from thread_struct to local
577 * buffer, then write that to userspace. Also set MSR_VSX in
578 * the saved MSR value to indicate that frame->mc_vregs
579 * contains valid data
580 */
581 if (current->thread.used_vsr) {
582 if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
583 return 1;
584 if (msr & MSR_VSX) {
585 if (copy_vsx_to_user(&tm_frame->mc_vsregs,
586 current))
587 return 1;
588 } else {
589 if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
590 return 1;
591 }
592
593 msr |= MSR_VSX;
594 }
595#endif /* CONFIG_VSX */
596#ifdef CONFIG_SPE
597 /* SPE regs are not checkpointed with TM, so this section is
598 * simply the same as in save_user_regs().
599 */
600 if (current->thread.used_spe) {
601 flush_spe_to_thread(current);
602 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
603 ELF_NEVRREG * sizeof(u32)))
604 return 1;
605 /* set MSR_SPE in the saved MSR value to indicate that
606 * frame->mc_vregs contains valid data */
607 msr |= MSR_SPE;
608 }
609
610 /* We always copy to/from spefscr */
611 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
612 return 1;
613#endif /* CONFIG_SPE */
614
615 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
616 return 1;
617 if (sigret) {
618 /* Set up the sigreturn trampoline: li 0,sigret; sc */
619 if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
620 || __put_user(PPC_INST_SC, &frame->tramp[1]))
621 return 1;
622 flush_icache_range((unsigned long) &frame->tramp[0],
623 (unsigned long) &frame->tramp[2]);
624 }
625
626 return 0;
627}
628#endif
629
630/*
631 * Restore the current user register values from the user stack,
632 * (except for MSR).
633 */
634static long restore_user_regs(struct pt_regs *regs,
635 struct mcontext __user *sr, int sig)
636{
637 long err;
638 unsigned int save_r2 = 0;
639 unsigned long msr;
640#ifdef CONFIG_VSX
641 int i;
642#endif
643
644 /*
645 * restore general registers but not including MSR or SOFTE. Also
646 * take care of keeping r2 (TLS) intact if not a signal
647 */
648 if (!sig)
649 save_r2 = (unsigned int)regs->gpr[2];
650 err = restore_general_regs(regs, sr);
651 regs->trap = 0;
652 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
653 if (!sig)
654 regs->gpr[2] = (unsigned long) save_r2;
655 if (err)
656 return 1;
657
658 /* if doing signal return, restore the previous little-endian mode */
659 if (sig)
660 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
661
662#ifdef CONFIG_ALTIVEC
663 /*
664 * Force the process to reload the altivec registers from
665 * current->thread when it next does altivec instructions
666 */
667 regs->msr &= ~MSR_VEC;
668 if (msr & MSR_VEC) {
669 /* restore altivec registers from the stack */
670 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
671 sizeof(sr->mc_vregs)))
672 return 1;
673 current->thread.used_vr = true;
674 } else if (current->thread.used_vr)
675 memset(¤t->thread.vr_state, 0,
676 ELF_NVRREG * sizeof(vector128));
677
678 /* Always get VRSAVE back */
679 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
680 return 1;
681 if (cpu_has_feature(CPU_FTR_ALTIVEC))
682 mtspr(SPRN_VRSAVE, current->thread.vrsave);
683#endif /* CONFIG_ALTIVEC */
684 if (copy_fpr_from_user(current, &sr->mc_fregs))
685 return 1;
686
687#ifdef CONFIG_VSX
688 /*
689 * Force the process to reload the VSX registers from
690 * current->thread when it next does VSX instruction.
691 */
692 regs->msr &= ~MSR_VSX;
693 if (msr & MSR_VSX) {
694 /*
695 * Restore altivec registers from the stack to a local
696 * buffer, then write this out to the thread_struct
697 */
698 if (copy_vsx_from_user(current, &sr->mc_vsregs))
699 return 1;
700 current->thread.used_vsr = true;
701 } else if (current->thread.used_vsr)
702 for (i = 0; i < 32 ; i++)
703 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
704#endif /* CONFIG_VSX */
705 /*
706 * force the process to reload the FP registers from
707 * current->thread when it next does FP instructions
708 */
709 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
710
711#ifdef CONFIG_SPE
712 /* force the process to reload the spe registers from
713 current->thread when it next does spe instructions */
714 regs->msr &= ~MSR_SPE;
715 if (msr & MSR_SPE) {
716 /* restore spe registers from the stack */
717 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
718 ELF_NEVRREG * sizeof(u32)))
719 return 1;
720 current->thread.used_spe = true;
721 } else if (current->thread.used_spe)
722 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
723
724 /* Always get SPEFSCR back */
725 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
726 return 1;
727#endif /* CONFIG_SPE */
728
729 return 0;
730}
731
732#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
733/*
734 * Restore the current user register values from the user stack, except for
735 * MSR, and recheckpoint the original checkpointed register state for processes
736 * in transactions.
737 */
738static long restore_tm_user_regs(struct pt_regs *regs,
739 struct mcontext __user *sr,
740 struct mcontext __user *tm_sr)
741{
742 long err;
743 unsigned long msr, msr_hi;
744#ifdef CONFIG_VSX
745 int i;
746#endif
747
748 if (tm_suspend_disabled)
749 return 1;
750 /*
751 * restore general registers but not including MSR or SOFTE. Also
752 * take care of keeping r2 (TLS) intact if not a signal.
753 * See comment in signal_64.c:restore_tm_sigcontexts();
754 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
755 * were set by the signal delivery.
756 */
757 err = restore_general_regs(regs, tm_sr);
758 err |= restore_general_regs(¤t->thread.ckpt_regs, sr);
759
760 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
761
762 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
763 if (err)
764 return 1;
765
766 /* Restore the previous little-endian mode */
767 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
768
769#ifdef CONFIG_ALTIVEC
770 regs->msr &= ~MSR_VEC;
771 if (msr & MSR_VEC) {
772 /* restore altivec registers from the stack */
773 if (__copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
774 sizeof(sr->mc_vregs)) ||
775 __copy_from_user(¤t->thread.vr_state,
776 &tm_sr->mc_vregs,
777 sizeof(sr->mc_vregs)))
778 return 1;
779 current->thread.used_vr = true;
780 } else if (current->thread.used_vr) {
781 memset(¤t->thread.vr_state, 0,
782 ELF_NVRREG * sizeof(vector128));
783 memset(¤t->thread.ckvr_state, 0,
784 ELF_NVRREG * sizeof(vector128));
785 }
786
787 /* Always get VRSAVE back */
788 if (__get_user(current->thread.ckvrsave,
789 (u32 __user *)&sr->mc_vregs[32]) ||
790 __get_user(current->thread.vrsave,
791 (u32 __user *)&tm_sr->mc_vregs[32]))
792 return 1;
793 if (cpu_has_feature(CPU_FTR_ALTIVEC))
794 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
795#endif /* CONFIG_ALTIVEC */
796
797 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
798
799 if (copy_fpr_from_user(current, &sr->mc_fregs) ||
800 copy_ckfpr_from_user(current, &tm_sr->mc_fregs))
801 return 1;
802
803#ifdef CONFIG_VSX
804 regs->msr &= ~MSR_VSX;
805 if (msr & MSR_VSX) {
806 /*
807 * Restore altivec registers from the stack to a local
808 * buffer, then write this out to the thread_struct
809 */
810 if (copy_vsx_from_user(current, &tm_sr->mc_vsregs) ||
811 copy_ckvsx_from_user(current, &sr->mc_vsregs))
812 return 1;
813 current->thread.used_vsr = true;
814 } else if (current->thread.used_vsr)
815 for (i = 0; i < 32 ; i++) {
816 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
817 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
818 }
819#endif /* CONFIG_VSX */
820
821#ifdef CONFIG_SPE
822 /* SPE regs are not checkpointed with TM, so this section is
823 * simply the same as in restore_user_regs().
824 */
825 regs->msr &= ~MSR_SPE;
826 if (msr & MSR_SPE) {
827 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
828 ELF_NEVRREG * sizeof(u32)))
829 return 1;
830 current->thread.used_spe = true;
831 } else if (current->thread.used_spe)
832 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
833
834 /* Always get SPEFSCR back */
835 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
836 + ELF_NEVRREG))
837 return 1;
838#endif /* CONFIG_SPE */
839
840 /* Get the top half of the MSR from the user context */
841 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
842 return 1;
843 msr_hi <<= 32;
844 /* If TM bits are set to the reserved value, it's an invalid context */
845 if (MSR_TM_RESV(msr_hi))
846 return 1;
847
848 /*
849 * Disabling preemption, since it is unsafe to be preempted
850 * with MSR[TS] set without recheckpointing.
851 */
852 preempt_disable();
853
854 /*
855 * CAUTION:
856 * After regs->MSR[TS] being updated, make sure that get_user(),
857 * put_user() or similar functions are *not* called. These
858 * functions can generate page faults which will cause the process
859 * to be de-scheduled with MSR[TS] set but without calling
860 * tm_recheckpoint(). This can cause a bug.
861 *
862 * Pull in the MSR TM bits from the user context
863 */
864 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK);
865 /* Now, recheckpoint. This loads up all of the checkpointed (older)
866 * registers, including FP and V[S]Rs. After recheckpointing, the
867 * transactional versions should be loaded.
868 */
869 tm_enable();
870 /* Make sure the transaction is marked as failed */
871 current->thread.tm_texasr |= TEXASR_FS;
872 /* This loads the checkpointed FP/VEC state, if used */
873 tm_recheckpoint(¤t->thread);
874
875 /* This loads the speculative FP/VEC state, if used */
876 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
877 if (msr & MSR_FP) {
878 load_fp_state(¤t->thread.fp_state);
879 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
880 }
881#ifdef CONFIG_ALTIVEC
882 if (msr & MSR_VEC) {
883 load_vr_state(¤t->thread.vr_state);
884 regs->msr |= MSR_VEC;
885 }
886#endif
887
888 preempt_enable();
889
890 return 0;
891}
892#endif
893
894#ifdef CONFIG_PPC64
895
896#define copy_siginfo_to_user copy_siginfo_to_user32
897
898#endif /* CONFIG_PPC64 */
899
900/*
901 * Set up a signal frame for a "real-time" signal handler
902 * (one which gets siginfo).
903 */
904int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
905 struct task_struct *tsk)
906{
907 struct rt_sigframe __user *rt_sf;
908 struct mcontext __user *frame;
909 struct mcontext __user *tm_frame = NULL;
910 void __user *addr;
911 unsigned long newsp = 0;
912 int sigret;
913 unsigned long tramp;
914 struct pt_regs *regs = tsk->thread.regs;
915
916 BUG_ON(tsk != current);
917
918 /* Set up Signal Frame */
919 /* Put a Real Time Context onto stack */
920 rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
921 addr = rt_sf;
922 if (unlikely(rt_sf == NULL))
923 goto badframe;
924
925 /* Put the siginfo & fill in most of the ucontext */
926 if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
927 || __put_user(0, &rt_sf->uc.uc_flags)
928 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
929 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
930 &rt_sf->uc.uc_regs)
931 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
932 goto badframe;
933
934 /* Save user registers on the stack */
935 frame = &rt_sf->uc.uc_mcontext;
936 addr = frame;
937 if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
938 sigret = 0;
939 tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
940 } else {
941 sigret = __NR_rt_sigreturn;
942 tramp = (unsigned long) frame->tramp;
943 }
944
945#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
946 tm_frame = &rt_sf->uc_transact.uc_mcontext;
947 if (MSR_TM_ACTIVE(regs->msr)) {
948 if (__put_user((unsigned long)&rt_sf->uc_transact,
949 &rt_sf->uc.uc_link) ||
950 __put_user((unsigned long)tm_frame,
951 &rt_sf->uc_transact.uc_regs))
952 goto badframe;
953 if (save_tm_user_regs(regs, frame, tm_frame, sigret))
954 goto badframe;
955 }
956 else
957#endif
958 {
959 if (__put_user(0, &rt_sf->uc.uc_link))
960 goto badframe;
961 if (save_user_regs(regs, frame, tm_frame, sigret, 1))
962 goto badframe;
963 }
964 regs->link = tramp;
965
966 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
967
968 /* create a stack frame for the caller of the handler */
969 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
970 addr = (void __user *)regs->gpr[1];
971 if (put_user(regs->gpr[1], (u32 __user *)newsp))
972 goto badframe;
973
974 /* Fill registers for signal handler */
975 regs->gpr[1] = newsp;
976 regs->gpr[3] = ksig->sig;
977 regs->gpr[4] = (unsigned long) &rt_sf->info;
978 regs->gpr[5] = (unsigned long) &rt_sf->uc;
979 regs->gpr[6] = (unsigned long) rt_sf;
980 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
981 /* enter the signal handler in native-endian mode */
982 regs->msr &= ~MSR_LE;
983 regs->msr |= (MSR_KERNEL & MSR_LE);
984 return 0;
985
986badframe:
987 if (show_unhandled_signals)
988 printk_ratelimited(KERN_INFO
989 "%s[%d]: bad frame in handle_rt_signal32: "
990 "%p nip %08lx lr %08lx\n",
991 tsk->comm, tsk->pid,
992 addr, regs->nip, regs->link);
993
994 return 1;
995}
996
997static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
998{
999 sigset_t set;
1000 struct mcontext __user *mcp;
1001
1002 if (get_sigset_t(&set, &ucp->uc_sigmask))
1003 return -EFAULT;
1004#ifdef CONFIG_PPC64
1005 {
1006 u32 cmcp;
1007
1008 if (__get_user(cmcp, &ucp->uc_regs))
1009 return -EFAULT;
1010 mcp = (struct mcontext __user *)(u64)cmcp;
1011 /* no need to check access_ok(mcp), since mcp < 4GB */
1012 }
1013#else
1014 if (__get_user(mcp, &ucp->uc_regs))
1015 return -EFAULT;
1016 if (!access_ok(mcp, sizeof(*mcp)))
1017 return -EFAULT;
1018#endif
1019 set_current_blocked(&set);
1020 if (restore_user_regs(regs, mcp, sig))
1021 return -EFAULT;
1022
1023 return 0;
1024}
1025
1026#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1027static int do_setcontext_tm(struct ucontext __user *ucp,
1028 struct ucontext __user *tm_ucp,
1029 struct pt_regs *regs)
1030{
1031 sigset_t set;
1032 struct mcontext __user *mcp;
1033 struct mcontext __user *tm_mcp;
1034 u32 cmcp;
1035 u32 tm_cmcp;
1036
1037 if (get_sigset_t(&set, &ucp->uc_sigmask))
1038 return -EFAULT;
1039
1040 if (__get_user(cmcp, &ucp->uc_regs) ||
1041 __get_user(tm_cmcp, &tm_ucp->uc_regs))
1042 return -EFAULT;
1043 mcp = (struct mcontext __user *)(u64)cmcp;
1044 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
1045 /* no need to check access_ok(mcp), since mcp < 4GB */
1046
1047 set_current_blocked(&set);
1048 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1049 return -EFAULT;
1050
1051 return 0;
1052}
1053#endif
1054
1055#ifdef CONFIG_PPC64
1056COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
1057 struct ucontext __user *, new_ctx, int, ctx_size)
1058#else
1059SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
1060 struct ucontext __user *, new_ctx, long, ctx_size)
1061#endif
1062{
1063 struct pt_regs *regs = current_pt_regs();
1064 int ctx_has_vsx_region = 0;
1065
1066#ifdef CONFIG_PPC64
1067 unsigned long new_msr = 0;
1068
1069 if (new_ctx) {
1070 struct mcontext __user *mcp;
1071 u32 cmcp;
1072
1073 /*
1074 * Get pointer to the real mcontext. No need for
1075 * access_ok since we are dealing with compat
1076 * pointers.
1077 */
1078 if (__get_user(cmcp, &new_ctx->uc_regs))
1079 return -EFAULT;
1080 mcp = (struct mcontext __user *)(u64)cmcp;
1081 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1082 return -EFAULT;
1083 }
1084 /*
1085 * Check that the context is not smaller than the original
1086 * size (with VMX but without VSX)
1087 */
1088 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1089 return -EINVAL;
1090 /*
1091 * If the new context state sets the MSR VSX bits but
1092 * it doesn't provide VSX state.
1093 */
1094 if ((ctx_size < sizeof(struct ucontext)) &&
1095 (new_msr & MSR_VSX))
1096 return -EINVAL;
1097 /* Does the context have enough room to store VSX data? */
1098 if (ctx_size >= sizeof(struct ucontext))
1099 ctx_has_vsx_region = 1;
1100#else
1101 /* Context size is for future use. Right now, we only make sure
1102 * we are passed something we understand
1103 */
1104 if (ctx_size < sizeof(struct ucontext))
1105 return -EINVAL;
1106#endif
1107 if (old_ctx != NULL) {
1108 struct mcontext __user *mctx;
1109
1110 /*
1111 * old_ctx might not be 16-byte aligned, in which
1112 * case old_ctx->uc_mcontext won't be either.
1113 * Because we have the old_ctx->uc_pad2 field
1114 * before old_ctx->uc_mcontext, we need to round down
1115 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1116 */
1117 mctx = (struct mcontext __user *)
1118 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1119 if (!access_ok(old_ctx, ctx_size)
1120 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
1121 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
1122 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
1123 return -EFAULT;
1124 }
1125 if (new_ctx == NULL)
1126 return 0;
1127 if (!access_ok(new_ctx, ctx_size) ||
1128 fault_in_pages_readable((u8 __user *)new_ctx, ctx_size))
1129 return -EFAULT;
1130
1131 /*
1132 * If we get a fault copying the context into the kernel's
1133 * image of the user's registers, we can't just return -EFAULT
1134 * because the user's registers will be corrupted. For instance
1135 * the NIP value may have been updated but not some of the
1136 * other registers. Given that we have done the access_ok
1137 * and successfully read the first and last bytes of the region
1138 * above, this should only happen in an out-of-memory situation
1139 * or if another thread unmaps the region containing the context.
1140 * We kill the task with a SIGSEGV in this situation.
1141 */
1142 if (do_setcontext(new_ctx, regs, 0))
1143 do_exit(SIGSEGV);
1144
1145 set_thread_flag(TIF_RESTOREALL);
1146 return 0;
1147}
1148
1149#ifdef CONFIG_PPC64
1150COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1151#else
1152SYSCALL_DEFINE0(rt_sigreturn)
1153#endif
1154{
1155 struct rt_sigframe __user *rt_sf;
1156 struct pt_regs *regs = current_pt_regs();
1157 int tm_restore = 0;
1158#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1159 struct ucontext __user *uc_transact;
1160 unsigned long msr_hi;
1161 unsigned long tmp;
1162#endif
1163 /* Always make any pending restarted system calls return -EINTR */
1164 current->restart_block.fn = do_no_restart_syscall;
1165
1166 rt_sf = (struct rt_sigframe __user *)
1167 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1168 if (!access_ok(rt_sf, sizeof(*rt_sf)))
1169 goto bad;
1170
1171#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1172 /*
1173 * If there is a transactional state then throw it away.
1174 * The purpose of a sigreturn is to destroy all traces of the
1175 * signal frame, this includes any transactional state created
1176 * within in. We only check for suspended as we can never be
1177 * active in the kernel, we are active, there is nothing better to
1178 * do than go ahead and Bad Thing later.
1179 * The cause is not important as there will never be a
1180 * recheckpoint so it's not user visible.
1181 */
1182 if (MSR_TM_SUSPENDED(mfmsr()))
1183 tm_reclaim_current(0);
1184
1185 if (__get_user(tmp, &rt_sf->uc.uc_link))
1186 goto bad;
1187 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1188 if (uc_transact) {
1189 u32 cmcp;
1190 struct mcontext __user *mcp;
1191
1192 if (__get_user(cmcp, &uc_transact->uc_regs))
1193 return -EFAULT;
1194 mcp = (struct mcontext __user *)(u64)cmcp;
1195 /* The top 32 bits of the MSR are stashed in the transactional
1196 * ucontext. */
1197 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1198 goto bad;
1199
1200 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1201 /* Trying to start TM on non TM system */
1202 if (!cpu_has_feature(CPU_FTR_TM))
1203 goto bad;
1204 /* We only recheckpoint on return if we're
1205 * transaction.
1206 */
1207 tm_restore = 1;
1208 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1209 goto bad;
1210 }
1211 }
1212 if (!tm_restore) {
1213 /*
1214 * Unset regs->msr because ucontext MSR TS is not
1215 * set, and recheckpoint was not called. This avoid
1216 * hitting a TM Bad thing at RFID
1217 */
1218 regs->msr &= ~MSR_TS_MASK;
1219 }
1220 /* Fall through, for non-TM restore */
1221#endif
1222 if (!tm_restore)
1223 if (do_setcontext(&rt_sf->uc, regs, 1))
1224 goto bad;
1225
1226 /*
1227 * It's not clear whether or why it is desirable to save the
1228 * sigaltstack setting on signal delivery and restore it on
1229 * signal return. But other architectures do this and we have
1230 * always done it up until now so it is probably better not to
1231 * change it. -- paulus
1232 */
1233#ifdef CONFIG_PPC64
1234 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1235 goto bad;
1236#else
1237 if (restore_altstack(&rt_sf->uc.uc_stack))
1238 goto bad;
1239#endif
1240 set_thread_flag(TIF_RESTOREALL);
1241 return 0;
1242
1243 bad:
1244 if (show_unhandled_signals)
1245 printk_ratelimited(KERN_INFO
1246 "%s[%d]: bad frame in sys_rt_sigreturn: "
1247 "%p nip %08lx lr %08lx\n",
1248 current->comm, current->pid,
1249 rt_sf, regs->nip, regs->link);
1250
1251 force_sig(SIGSEGV);
1252 return 0;
1253}
1254
1255#ifdef CONFIG_PPC32
1256SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1257 int, ndbg, struct sig_dbg_op __user *, dbg)
1258{
1259 struct pt_regs *regs = current_pt_regs();
1260 struct sig_dbg_op op;
1261 int i;
1262 unsigned long new_msr = regs->msr;
1263#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1264 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1265#endif
1266
1267 for (i=0; i<ndbg; i++) {
1268 if (copy_from_user(&op, dbg + i, sizeof(op)))
1269 return -EFAULT;
1270 switch (op.dbg_type) {
1271 case SIG_DBG_SINGLE_STEPPING:
1272#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1273 if (op.dbg_value) {
1274 new_msr |= MSR_DE;
1275 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1276 } else {
1277 new_dbcr0 &= ~DBCR0_IC;
1278 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1279 current->thread.debug.dbcr1)) {
1280 new_msr &= ~MSR_DE;
1281 new_dbcr0 &= ~DBCR0_IDM;
1282 }
1283 }
1284#else
1285 if (op.dbg_value)
1286 new_msr |= MSR_SE;
1287 else
1288 new_msr &= ~MSR_SE;
1289#endif
1290 break;
1291 case SIG_DBG_BRANCH_TRACING:
1292#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1293 return -EINVAL;
1294#else
1295 if (op.dbg_value)
1296 new_msr |= MSR_BE;
1297 else
1298 new_msr &= ~MSR_BE;
1299#endif
1300 break;
1301
1302 default:
1303 return -EINVAL;
1304 }
1305 }
1306
1307 /* We wait until here to actually install the values in the
1308 registers so if we fail in the above loop, it will not
1309 affect the contents of these registers. After this point,
1310 failure is a problem, anyway, and it's very unlikely unless
1311 the user is really doing something wrong. */
1312 regs->msr = new_msr;
1313#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1314 current->thread.debug.dbcr0 = new_dbcr0;
1315#endif
1316
1317 if (!access_ok(ctx, sizeof(*ctx)) ||
1318 fault_in_pages_readable((u8 __user *)ctx, sizeof(*ctx)))
1319 return -EFAULT;
1320
1321 /*
1322 * If we get a fault copying the context into the kernel's
1323 * image of the user's registers, we can't just return -EFAULT
1324 * because the user's registers will be corrupted. For instance
1325 * the NIP value may have been updated but not some of the
1326 * other registers. Given that we have done the access_ok
1327 * and successfully read the first and last bytes of the region
1328 * above, this should only happen in an out-of-memory situation
1329 * or if another thread unmaps the region containing the context.
1330 * We kill the task with a SIGSEGV in this situation.
1331 */
1332 if (do_setcontext(ctx, regs, 1)) {
1333 if (show_unhandled_signals)
1334 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1335 "sys_debug_setcontext: %p nip %08lx "
1336 "lr %08lx\n",
1337 current->comm, current->pid,
1338 ctx, regs->nip, regs->link);
1339
1340 force_sig(SIGSEGV);
1341 goto out;
1342 }
1343
1344 /*
1345 * It's not clear whether or why it is desirable to save the
1346 * sigaltstack setting on signal delivery and restore it on
1347 * signal return. But other architectures do this and we have
1348 * always done it up until now so it is probably better not to
1349 * change it. -- paulus
1350 */
1351 restore_altstack(&ctx->uc_stack);
1352
1353 set_thread_flag(TIF_RESTOREALL);
1354 out:
1355 return 0;
1356}
1357#endif
1358
1359/*
1360 * OK, we're invoking a handler
1361 */
1362int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
1363 struct task_struct *tsk)
1364{
1365 struct sigcontext __user *sc;
1366 struct sigframe __user *frame;
1367 struct mcontext __user *tm_mctx = NULL;
1368 unsigned long newsp = 0;
1369 int sigret;
1370 unsigned long tramp;
1371 struct pt_regs *regs = tsk->thread.regs;
1372
1373 BUG_ON(tsk != current);
1374
1375 /* Set up Signal Frame */
1376 frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
1377 if (unlikely(frame == NULL))
1378 goto badframe;
1379 sc = (struct sigcontext __user *) &frame->sctx;
1380
1381#if _NSIG != 64
1382#error "Please adjust handle_signal()"
1383#endif
1384 if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
1385 || __put_user(oldset->sig[0], &sc->oldmask)
1386#ifdef CONFIG_PPC64
1387 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1388#else
1389 || __put_user(oldset->sig[1], &sc->_unused[3])
1390#endif
1391 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1392 || __put_user(ksig->sig, &sc->signal))
1393 goto badframe;
1394
1395 if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
1396 sigret = 0;
1397 tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
1398 } else {
1399 sigret = __NR_sigreturn;
1400 tramp = (unsigned long) frame->mctx.tramp;
1401 }
1402
1403#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1404 tm_mctx = &frame->mctx_transact;
1405 if (MSR_TM_ACTIVE(regs->msr)) {
1406 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1407 sigret))
1408 goto badframe;
1409 }
1410 else
1411#endif
1412 {
1413 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1414 goto badframe;
1415 }
1416
1417 regs->link = tramp;
1418
1419 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1420
1421 /* create a stack frame for the caller of the handler */
1422 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1423 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1424 goto badframe;
1425
1426 regs->gpr[1] = newsp;
1427 regs->gpr[3] = ksig->sig;
1428 regs->gpr[4] = (unsigned long) sc;
1429 regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
1430 /* enter the signal handler in big-endian mode */
1431 regs->msr &= ~MSR_LE;
1432 return 0;
1433
1434badframe:
1435 if (show_unhandled_signals)
1436 printk_ratelimited(KERN_INFO
1437 "%s[%d]: bad frame in handle_signal32: "
1438 "%p nip %08lx lr %08lx\n",
1439 tsk->comm, tsk->pid,
1440 frame, regs->nip, regs->link);
1441
1442 return 1;
1443}
1444
1445/*
1446 * Do a signal return; undo the signal stack.
1447 */
1448#ifdef CONFIG_PPC64
1449COMPAT_SYSCALL_DEFINE0(sigreturn)
1450#else
1451SYSCALL_DEFINE0(sigreturn)
1452#endif
1453{
1454 struct pt_regs *regs = current_pt_regs();
1455 struct sigframe __user *sf;
1456 struct sigcontext __user *sc;
1457 struct sigcontext sigctx;
1458 struct mcontext __user *sr;
1459 void __user *addr;
1460 sigset_t set;
1461#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1462 struct mcontext __user *mcp, *tm_mcp;
1463 unsigned long msr_hi;
1464#endif
1465
1466 /* Always make any pending restarted system calls return -EINTR */
1467 current->restart_block.fn = do_no_restart_syscall;
1468
1469 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1470 sc = &sf->sctx;
1471 addr = sc;
1472 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1473 goto badframe;
1474
1475#ifdef CONFIG_PPC64
1476 /*
1477 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1478 * unused part of the signal stackframe
1479 */
1480 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1481#else
1482 set.sig[0] = sigctx.oldmask;
1483 set.sig[1] = sigctx._unused[3];
1484#endif
1485 set_current_blocked(&set);
1486
1487#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1488 mcp = (struct mcontext __user *)&sf->mctx;
1489 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1490 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1491 goto badframe;
1492 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1493 if (!cpu_has_feature(CPU_FTR_TM))
1494 goto badframe;
1495 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1496 goto badframe;
1497 } else
1498#endif
1499 {
1500 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1501 addr = sr;
1502 if (!access_ok(sr, sizeof(*sr))
1503 || restore_user_regs(regs, sr, 1))
1504 goto badframe;
1505 }
1506
1507 set_thread_flag(TIF_RESTOREALL);
1508 return 0;
1509
1510badframe:
1511 if (show_unhandled_signals)
1512 printk_ratelimited(KERN_INFO
1513 "%s[%d]: bad frame in sys_sigreturn: "
1514 "%p nip %08lx lr %08lx\n",
1515 current->comm, current->pid,
1516 addr, regs->nip, regs->link);
1517
1518 force_sig(SIGSEGV);
1519 return 0;
1520}