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