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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 <asm/syscalls_32.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
236unsigned long get_min_sigframe_size_32(void)
237{
238 return max(sizeof(struct rt_sigframe) + __SIGNAL_FRAMESIZE + 16,
239 sizeof(struct sigframe) + __SIGNAL_FRAMESIZE);
240}
241
242/*
243 * Save the current user registers on the user stack.
244 * We only save the altivec/spe registers if the process has used
245 * altivec/spe instructions at some point.
246 */
247static void prepare_save_user_regs(int ctx_has_vsx_region)
248{
249 /* Make sure floating point registers are stored in regs */
250 flush_fp_to_thread(current);
251#ifdef CONFIG_ALTIVEC
252 if (current->thread.used_vr)
253 flush_altivec_to_thread(current);
254 if (cpu_has_feature(CPU_FTR_ALTIVEC))
255 current->thread.vrsave = mfspr(SPRN_VRSAVE);
256#endif
257#ifdef CONFIG_VSX
258 if (current->thread.used_vsr && ctx_has_vsx_region)
259 flush_vsx_to_thread(current);
260#endif
261#ifdef CONFIG_SPE
262 if (current->thread.used_spe)
263 flush_spe_to_thread(current);
264#endif
265}
266
267static __always_inline int
268__unsafe_save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
269 struct mcontext __user *tm_frame, int ctx_has_vsx_region)
270{
271 unsigned long msr = regs->msr;
272
273 /* save general registers */
274 unsafe_save_general_regs(regs, frame, failed);
275
276#ifdef CONFIG_ALTIVEC
277 /* save altivec registers */
278 if (current->thread.used_vr) {
279 unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
280 ELF_NVRREG * sizeof(vector128), failed);
281 /* set MSR_VEC in the saved MSR value to indicate that
282 frame->mc_vregs contains valid data */
283 msr |= MSR_VEC;
284 }
285 /* else assert((regs->msr & MSR_VEC) == 0) */
286
287 /* We always copy to/from vrsave, it's 0 if we don't have or don't
288 * use altivec. Since VSCR only contains 32 bits saved in the least
289 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
290 * most significant bits of that same vector. --BenH
291 * Note that the current VRSAVE value is in the SPR at this point.
292 */
293 unsafe_put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32],
294 failed);
295#endif /* CONFIG_ALTIVEC */
296 unsafe_copy_fpr_to_user(&frame->mc_fregs, current, failed);
297
298 /*
299 * Clear the MSR VSX bit to indicate there is no valid state attached
300 * to this context, except in the specific case below where we set it.
301 */
302 msr &= ~MSR_VSX;
303#ifdef CONFIG_VSX
304 /*
305 * Copy VSR 0-31 upper half from thread_struct to local
306 * buffer, then write that to userspace. Also set MSR_VSX in
307 * the saved MSR value to indicate that frame->mc_vregs
308 * contains valid data
309 */
310 if (current->thread.used_vsr && ctx_has_vsx_region) {
311 unsafe_copy_vsx_to_user(&frame->mc_vsregs, current, failed);
312 msr |= MSR_VSX;
313 }
314#endif /* CONFIG_VSX */
315#ifdef CONFIG_SPE
316 /* save spe registers */
317 if (current->thread.used_spe) {
318 unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
319 ELF_NEVRREG * sizeof(u32), failed);
320 /* set MSR_SPE in the saved MSR value to indicate that
321 frame->mc_vregs contains valid data */
322 msr |= MSR_SPE;
323 }
324 /* else assert((regs->msr & MSR_SPE) == 0) */
325
326 /* We always copy to/from spefscr */
327 unsafe_put_user(current->thread.spefscr,
328 (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
329#endif /* CONFIG_SPE */
330
331 unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
332
333 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
334 * can check it on the restore to see if TM is active
335 */
336 if (tm_frame)
337 unsafe_put_user(0, &tm_frame->mc_gregs[PT_MSR], failed);
338
339 return 0;
340
341failed:
342 return 1;
343}
344
345#define unsafe_save_user_regs(regs, frame, tm_frame, has_vsx, label) do { \
346 if (__unsafe_save_user_regs(regs, frame, tm_frame, has_vsx)) \
347 goto label; \
348} while (0)
349
350#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
351/*
352 * Save the current user registers on the user stack.
353 * We only save the altivec/spe registers if the process has used
354 * altivec/spe instructions at some point.
355 * We also save the transactional registers to a second ucontext in the
356 * frame.
357 *
358 * See __unsafe_save_user_regs() and signal_64.c:setup_tm_sigcontexts().
359 */
360static void prepare_save_tm_user_regs(void)
361{
362 WARN_ON(tm_suspend_disabled);
363
364 if (cpu_has_feature(CPU_FTR_ALTIVEC))
365 current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
366}
367
368static __always_inline int
369save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
370 struct mcontext __user *tm_frame, unsigned long msr)
371{
372 /* Save both sets of general registers */
373 unsafe_save_general_regs(¤t->thread.ckpt_regs, frame, failed);
374 unsafe_save_general_regs(regs, tm_frame, failed);
375
376 /* Stash the top half of the 64bit MSR into the 32bit MSR word
377 * of the transactional mcontext. This way we have a backward-compatible
378 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
379 * also look at what type of transaction (T or S) was active at the
380 * time of the signal.
381 */
382 unsafe_put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR], failed);
383
384 /* save altivec registers */
385 if (current->thread.used_vr) {
386 unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
387 ELF_NVRREG * sizeof(vector128), failed);
388 if (msr & MSR_VEC)
389 unsafe_copy_to_user(&tm_frame->mc_vregs,
390 ¤t->thread.vr_state,
391 ELF_NVRREG * sizeof(vector128), failed);
392 else
393 unsafe_copy_to_user(&tm_frame->mc_vregs,
394 ¤t->thread.ckvr_state,
395 ELF_NVRREG * sizeof(vector128), failed);
396
397 /* set MSR_VEC in the saved MSR value to indicate that
398 * frame->mc_vregs contains valid data
399 */
400 msr |= MSR_VEC;
401 }
402
403 /* We always copy to/from vrsave, it's 0 if we don't have or don't
404 * use altivec. Since VSCR only contains 32 bits saved in the least
405 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
406 * most significant bits of that same vector. --BenH
407 */
408 unsafe_put_user(current->thread.ckvrsave,
409 (u32 __user *)&frame->mc_vregs[32], failed);
410 if (msr & MSR_VEC)
411 unsafe_put_user(current->thread.vrsave,
412 (u32 __user *)&tm_frame->mc_vregs[32], failed);
413 else
414 unsafe_put_user(current->thread.ckvrsave,
415 (u32 __user *)&tm_frame->mc_vregs[32], failed);
416
417 unsafe_copy_ckfpr_to_user(&frame->mc_fregs, current, failed);
418 if (msr & MSR_FP)
419 unsafe_copy_fpr_to_user(&tm_frame->mc_fregs, current, failed);
420 else
421 unsafe_copy_ckfpr_to_user(&tm_frame->mc_fregs, current, failed);
422
423 /*
424 * Copy VSR 0-31 upper half from thread_struct to local
425 * buffer, then write that to userspace. Also set MSR_VSX in
426 * the saved MSR value to indicate that frame->mc_vregs
427 * contains valid data
428 */
429 if (current->thread.used_vsr) {
430 unsafe_copy_ckvsx_to_user(&frame->mc_vsregs, current, failed);
431 if (msr & MSR_VSX)
432 unsafe_copy_vsx_to_user(&tm_frame->mc_vsregs, current, failed);
433 else
434 unsafe_copy_ckvsx_to_user(&tm_frame->mc_vsregs, current, failed);
435
436 msr |= MSR_VSX;
437 }
438
439 unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
440
441 return 0;
442
443failed:
444 return 1;
445}
446#else
447static void prepare_save_tm_user_regs(void) { }
448
449static __always_inline int
450save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
451 struct mcontext __user *tm_frame, unsigned long msr)
452{
453 return 0;
454}
455#endif
456
457#define unsafe_save_tm_user_regs(regs, frame, tm_frame, msr, label) do { \
458 if (save_tm_user_regs_unsafe(regs, frame, tm_frame, msr)) \
459 goto label; \
460} while (0)
461
462/*
463 * Restore the current user register values from the user stack,
464 * (except for MSR).
465 */
466static long restore_user_regs(struct pt_regs *regs,
467 struct mcontext __user *sr, int sig)
468{
469 unsigned int save_r2 = 0;
470 unsigned long msr;
471#ifdef CONFIG_VSX
472 int i;
473#endif
474
475 if (!user_read_access_begin(sr, sizeof(*sr)))
476 return 1;
477 /*
478 * restore general registers but not including MSR or SOFTE. Also
479 * take care of keeping r2 (TLS) intact if not a signal
480 */
481 if (!sig)
482 save_r2 = (unsigned int)regs->gpr[2];
483 unsafe_restore_general_regs(regs, sr, failed);
484 set_trap_norestart(regs);
485 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
486 if (!sig)
487 regs->gpr[2] = (unsigned long) save_r2;
488
489 /* if doing signal return, restore the previous little-endian mode */
490 if (sig)
491 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (msr & MSR_LE));
492
493#ifdef CONFIG_ALTIVEC
494 /*
495 * Force the process to reload the altivec registers from
496 * current->thread when it next does altivec instructions
497 */
498 regs_set_return_msr(regs, regs->msr & ~MSR_VEC);
499 if (msr & MSR_VEC) {
500 /* restore altivec registers from the stack */
501 unsafe_copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
502 sizeof(sr->mc_vregs), failed);
503 current->thread.used_vr = true;
504 } else if (current->thread.used_vr)
505 memset(¤t->thread.vr_state, 0,
506 ELF_NVRREG * sizeof(vector128));
507
508 /* Always get VRSAVE back */
509 unsafe_get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32], failed);
510 if (cpu_has_feature(CPU_FTR_ALTIVEC))
511 mtspr(SPRN_VRSAVE, current->thread.vrsave);
512#endif /* CONFIG_ALTIVEC */
513 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
514
515#ifdef CONFIG_VSX
516 /*
517 * Force the process to reload the VSX registers from
518 * current->thread when it next does VSX instruction.
519 */
520 regs_set_return_msr(regs, regs->msr & ~MSR_VSX);
521 if (msr & MSR_VSX) {
522 /*
523 * Restore altivec registers from the stack to a local
524 * buffer, then write this out to the thread_struct
525 */
526 unsafe_copy_vsx_from_user(current, &sr->mc_vsregs, failed);
527 current->thread.used_vsr = true;
528 } else if (current->thread.used_vsr)
529 for (i = 0; i < 32 ; i++)
530 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
531#endif /* CONFIG_VSX */
532 /*
533 * force the process to reload the FP registers from
534 * current->thread when it next does FP instructions
535 */
536 regs_set_return_msr(regs, regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1));
537
538#ifdef CONFIG_SPE
539 /*
540 * Force the process to reload the spe registers from
541 * current->thread when it next does spe instructions.
542 * Since this is user ABI, we must enforce the sizing.
543 */
544 BUILD_BUG_ON(sizeof(current->thread.spe) != ELF_NEVRREG * sizeof(u32));
545 regs_set_return_msr(regs, regs->msr & ~MSR_SPE);
546 if (msr & MSR_SPE) {
547 /* restore spe registers from the stack */
548 unsafe_copy_from_user(¤t->thread.spe, &sr->mc_vregs,
549 sizeof(current->thread.spe), failed);
550 current->thread.used_spe = true;
551 } else if (current->thread.used_spe)
552 memset(¤t->thread.spe, 0, sizeof(current->thread.spe));
553
554 /* Always get SPEFSCR back */
555 unsafe_get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG, failed);
556#endif /* CONFIG_SPE */
557
558 user_read_access_end();
559 return 0;
560
561failed:
562 user_read_access_end();
563 return 1;
564}
565
566#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
567/*
568 * Restore the current user register values from the user stack, except for
569 * MSR, and recheckpoint the original checkpointed register state for processes
570 * in transactions.
571 */
572static long restore_tm_user_regs(struct pt_regs *regs,
573 struct mcontext __user *sr,
574 struct mcontext __user *tm_sr)
575{
576 unsigned long msr, msr_hi;
577 int i;
578
579 if (tm_suspend_disabled)
580 return 1;
581 /*
582 * restore general registers but not including MSR or SOFTE. Also
583 * take care of keeping r2 (TLS) intact if not a signal.
584 * See comment in signal_64.c:restore_tm_sigcontexts();
585 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
586 * were set by the signal delivery.
587 */
588 if (!user_read_access_begin(sr, sizeof(*sr)))
589 return 1;
590
591 unsafe_restore_general_regs(¤t->thread.ckpt_regs, sr, failed);
592 unsafe_get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP], failed);
593 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed);
594
595 /* Restore the previous little-endian mode */
596 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (msr & MSR_LE));
597
598 regs_set_return_msr(regs, regs->msr & ~MSR_VEC);
599 if (msr & MSR_VEC) {
600 /* restore altivec registers from the stack */
601 unsafe_copy_from_user(¤t->thread.ckvr_state, &sr->mc_vregs,
602 sizeof(sr->mc_vregs), failed);
603 current->thread.used_vr = true;
604 } else if (current->thread.used_vr) {
605 memset(¤t->thread.vr_state, 0,
606 ELF_NVRREG * sizeof(vector128));
607 memset(¤t->thread.ckvr_state, 0,
608 ELF_NVRREG * sizeof(vector128));
609 }
610
611 /* Always get VRSAVE back */
612 unsafe_get_user(current->thread.ckvrsave,
613 (u32 __user *)&sr->mc_vregs[32], failed);
614 if (cpu_has_feature(CPU_FTR_ALTIVEC))
615 mtspr(SPRN_VRSAVE, current->thread.ckvrsave);
616
617 regs_set_return_msr(regs, regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1));
618
619 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed);
620
621 regs_set_return_msr(regs, regs->msr & ~MSR_VSX);
622 if (msr & MSR_VSX) {
623 /*
624 * Restore altivec registers from the stack to a local
625 * buffer, then write this out to the thread_struct
626 */
627 unsafe_copy_ckvsx_from_user(current, &sr->mc_vsregs, failed);
628 current->thread.used_vsr = true;
629 } else if (current->thread.used_vsr)
630 for (i = 0; i < 32 ; i++) {
631 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
632 current->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
633 }
634
635 user_read_access_end();
636
637 if (!user_read_access_begin(tm_sr, sizeof(*tm_sr)))
638 return 1;
639
640 unsafe_restore_general_regs(regs, tm_sr, failed);
641
642 /* restore altivec registers from the stack */
643 if (msr & MSR_VEC)
644 unsafe_copy_from_user(¤t->thread.vr_state, &tm_sr->mc_vregs,
645 sizeof(sr->mc_vregs), failed);
646
647 /* Always get VRSAVE back */
648 unsafe_get_user(current->thread.vrsave,
649 (u32 __user *)&tm_sr->mc_vregs[32], failed);
650
651 unsafe_copy_ckfpr_from_user(current, &tm_sr->mc_fregs, failed);
652
653 if (msr & MSR_VSX) {
654 /*
655 * Restore altivec registers from the stack to a local
656 * buffer, then write this out to the thread_struct
657 */
658 unsafe_copy_vsx_from_user(current, &tm_sr->mc_vsregs, failed);
659 current->thread.used_vsr = true;
660 }
661
662 /* Get the top half of the MSR from the user context */
663 unsafe_get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR], failed);
664 msr_hi <<= 32;
665
666 user_read_access_end();
667
668 /* If TM bits are set to the reserved value, it's an invalid context */
669 if (MSR_TM_RESV(msr_hi))
670 return 1;
671
672 /*
673 * Disabling preemption, since it is unsafe to be preempted
674 * with MSR[TS] set without recheckpointing.
675 */
676 preempt_disable();
677
678 /*
679 * CAUTION:
680 * After regs->MSR[TS] being updated, make sure that get_user(),
681 * put_user() or similar functions are *not* called. These
682 * functions can generate page faults which will cause the process
683 * to be de-scheduled with MSR[TS] set but without calling
684 * tm_recheckpoint(). This can cause a bug.
685 *
686 * Pull in the MSR TM bits from the user context
687 */
688 regs_set_return_msr(regs, (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK));
689 /* Now, recheckpoint. This loads up all of the checkpointed (older)
690 * registers, including FP and V[S]Rs. After recheckpointing, the
691 * transactional versions should be loaded.
692 */
693 tm_enable();
694 /* Make sure the transaction is marked as failed */
695 current->thread.tm_texasr |= TEXASR_FS;
696 /* This loads the checkpointed FP/VEC state, if used */
697 tm_recheckpoint(¤t->thread);
698
699 /* This loads the speculative FP/VEC state, if used */
700 msr_check_and_set(msr & (MSR_FP | MSR_VEC));
701 if (msr & MSR_FP) {
702 load_fp_state(¤t->thread.fp_state);
703 regs_set_return_msr(regs, regs->msr | (MSR_FP | current->thread.fpexc_mode));
704 }
705 if (msr & MSR_VEC) {
706 load_vr_state(¤t->thread.vr_state);
707 regs_set_return_msr(regs, regs->msr | MSR_VEC);
708 }
709
710 preempt_enable();
711
712 return 0;
713
714failed:
715 user_read_access_end();
716 return 1;
717}
718#else
719static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *sr,
720 struct mcontext __user *tm_sr)
721{
722 return 0;
723}
724#endif
725
726#ifdef CONFIG_PPC64
727
728#define copy_siginfo_to_user copy_siginfo_to_user32
729
730#endif /* CONFIG_PPC64 */
731
732/*
733 * Set up a signal frame for a "real-time" signal handler
734 * (one which gets siginfo).
735 */
736int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
737 struct task_struct *tsk)
738{
739 struct rt_sigframe __user *frame;
740 struct mcontext __user *mctx;
741 struct mcontext __user *tm_mctx = NULL;
742 unsigned long newsp = 0;
743 unsigned long tramp;
744 struct pt_regs *regs = tsk->thread.regs;
745 /* Save the thread's msr before get_tm_stackpointer() changes it */
746 unsigned long msr = regs->msr;
747
748 /* Set up Signal Frame */
749 frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
750 mctx = &frame->uc.uc_mcontext;
751#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
752 tm_mctx = &frame->uc_transact.uc_mcontext;
753#endif
754 if (MSR_TM_ACTIVE(msr))
755 prepare_save_tm_user_regs();
756 else
757 prepare_save_user_regs(1);
758
759 if (!user_access_begin(frame, sizeof(*frame)))
760 goto badframe;
761
762 /* Put the siginfo & fill in most of the ucontext */
763 unsafe_put_user(0, &frame->uc.uc_flags, failed);
764#ifdef CONFIG_PPC64
765 unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
766#else
767 unsafe_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
768#endif
769 unsafe_put_user(to_user_ptr(&frame->uc.uc_mcontext), &frame->uc.uc_regs, failed);
770
771 if (MSR_TM_ACTIVE(msr)) {
772#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
773 unsafe_put_user((unsigned long)&frame->uc_transact,
774 &frame->uc.uc_link, failed);
775 unsafe_put_user((unsigned long)tm_mctx,
776 &frame->uc_transact.uc_regs, failed);
777#endif
778 unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
779 } else {
780 unsafe_put_user(0, &frame->uc.uc_link, failed);
781 unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
782 }
783
784 /* Save user registers on the stack */
785 if (tsk->mm->context.vdso) {
786 tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp_rt32);
787 } else {
788 tramp = (unsigned long)mctx->mc_pad;
789 unsafe_put_user(PPC_RAW_LI(_R0, __NR_rt_sigreturn), &mctx->mc_pad[0], failed);
790 unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
791 asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
792 }
793 unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed);
794
795 user_access_end();
796
797 if (copy_siginfo_to_user(&frame->info, &ksig->info))
798 goto badframe;
799
800 regs->link = tramp;
801
802#ifdef CONFIG_PPC_FPU_REGS
803 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
804#endif
805
806 /* create a stack frame for the caller of the handler */
807 newsp = ((unsigned long)frame) - (__SIGNAL_FRAMESIZE + 16);
808 if (put_user(regs->gpr[1], (u32 __user *)newsp))
809 goto badframe;
810
811 /* Fill registers for signal handler */
812 regs->gpr[1] = newsp;
813 regs->gpr[3] = ksig->sig;
814 regs->gpr[4] = (unsigned long)&frame->info;
815 regs->gpr[5] = (unsigned long)&frame->uc;
816 regs->gpr[6] = (unsigned long)frame;
817 regs_set_return_ip(regs, (unsigned long) ksig->ka.sa.sa_handler);
818 /* enter the signal handler in native-endian mode */
819 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (MSR_KERNEL & MSR_LE));
820
821 return 0;
822
823failed:
824 user_access_end();
825
826badframe:
827 signal_fault(tsk, regs, "handle_rt_signal32", frame);
828
829 return 1;
830}
831
832/*
833 * OK, we're invoking a handler
834 */
835int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
836 struct task_struct *tsk)
837{
838 struct sigcontext __user *sc;
839 struct sigframe __user *frame;
840 struct mcontext __user *mctx;
841 struct mcontext __user *tm_mctx = NULL;
842 unsigned long newsp = 0;
843 unsigned long tramp;
844 struct pt_regs *regs = tsk->thread.regs;
845 /* Save the thread's msr before get_tm_stackpointer() changes it */
846 unsigned long msr = regs->msr;
847
848 /* Set up Signal Frame */
849 frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
850 mctx = &frame->mctx;
851#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
852 tm_mctx = &frame->mctx_transact;
853#endif
854 if (MSR_TM_ACTIVE(msr))
855 prepare_save_tm_user_regs();
856 else
857 prepare_save_user_regs(1);
858
859 if (!user_access_begin(frame, sizeof(*frame)))
860 goto badframe;
861 sc = (struct sigcontext __user *) &frame->sctx;
862
863#if _NSIG != 64
864#error "Please adjust handle_signal()"
865#endif
866 unsafe_put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler, failed);
867 unsafe_put_user(oldset->sig[0], &sc->oldmask, failed);
868#ifdef CONFIG_PPC64
869 unsafe_put_user((oldset->sig[0] >> 32), &sc->_unused[3], failed);
870#else
871 unsafe_put_user(oldset->sig[1], &sc->_unused[3], failed);
872#endif
873 unsafe_put_user(to_user_ptr(mctx), &sc->regs, failed);
874 unsafe_put_user(ksig->sig, &sc->signal, failed);
875
876 if (MSR_TM_ACTIVE(msr))
877 unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
878 else
879 unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
880
881 if (tsk->mm->context.vdso) {
882 tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp32);
883 } else {
884 tramp = (unsigned long)mctx->mc_pad;
885 unsafe_put_user(PPC_RAW_LI(_R0, __NR_sigreturn), &mctx->mc_pad[0], failed);
886 unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
887 asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
888 }
889 user_access_end();
890
891 regs->link = tramp;
892
893#ifdef CONFIG_PPC_FPU_REGS
894 tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
895#endif
896
897 /* create a stack frame for the caller of the handler */
898 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
899 if (put_user(regs->gpr[1], (u32 __user *)newsp))
900 goto badframe;
901
902 regs->gpr[1] = newsp;
903 regs->gpr[3] = ksig->sig;
904 regs->gpr[4] = (unsigned long) sc;
905 regs_set_return_ip(regs, (unsigned long) ksig->ka.sa.sa_handler);
906 /* enter the signal handler in native-endian mode */
907 regs_set_return_msr(regs, (regs->msr & ~MSR_LE) | (MSR_KERNEL & MSR_LE));
908
909 return 0;
910
911failed:
912 user_access_end();
913
914badframe:
915 signal_fault(tsk, regs, "handle_signal32", frame);
916
917 return 1;
918}
919
920static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
921{
922 sigset_t set;
923 struct mcontext __user *mcp;
924
925 if (!user_read_access_begin(ucp, sizeof(*ucp)))
926 return -EFAULT;
927
928 unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
929#ifdef CONFIG_PPC64
930 {
931 u32 cmcp;
932
933 unsafe_get_user(cmcp, &ucp->uc_regs, failed);
934 mcp = (struct mcontext __user *)(u64)cmcp;
935 }
936#else
937 unsafe_get_user(mcp, &ucp->uc_regs, failed);
938#endif
939 user_read_access_end();
940
941 set_current_blocked(&set);
942 if (restore_user_regs(regs, mcp, sig))
943 return -EFAULT;
944
945 return 0;
946
947failed:
948 user_read_access_end();
949 return -EFAULT;
950}
951
952#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
953static int do_setcontext_tm(struct ucontext __user *ucp,
954 struct ucontext __user *tm_ucp,
955 struct pt_regs *regs)
956{
957 sigset_t set;
958 struct mcontext __user *mcp;
959 struct mcontext __user *tm_mcp;
960 u32 cmcp;
961 u32 tm_cmcp;
962
963 if (!user_read_access_begin(ucp, sizeof(*ucp)))
964 return -EFAULT;
965
966 unsafe_get_sigset_t(&set, &ucp->uc_sigmask, failed);
967 unsafe_get_user(cmcp, &ucp->uc_regs, failed);
968
969 user_read_access_end();
970
971 if (__get_user(tm_cmcp, &tm_ucp->uc_regs))
972 return -EFAULT;
973 mcp = (struct mcontext __user *)(u64)cmcp;
974 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
975 /* no need to check access_ok(mcp), since mcp < 4GB */
976
977 set_current_blocked(&set);
978 if (restore_tm_user_regs(regs, mcp, tm_mcp))
979 return -EFAULT;
980
981 return 0;
982
983failed:
984 user_read_access_end();
985 return -EFAULT;
986}
987#endif
988
989#ifdef CONFIG_PPC64
990COMPAT_SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
991 struct ucontext __user *, new_ctx, int, ctx_size)
992#else
993SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
994 struct ucontext __user *, new_ctx, long, ctx_size)
995#endif
996{
997 struct pt_regs *regs = current_pt_regs();
998 int ctx_has_vsx_region = 0;
999
1000#ifdef CONFIG_PPC64
1001 unsigned long new_msr = 0;
1002
1003 if (new_ctx) {
1004 struct mcontext __user *mcp;
1005 u32 cmcp;
1006
1007 /*
1008 * Get pointer to the real mcontext. No need for
1009 * access_ok since we are dealing with compat
1010 * pointers.
1011 */
1012 if (__get_user(cmcp, &new_ctx->uc_regs))
1013 return -EFAULT;
1014 mcp = (struct mcontext __user *)(u64)cmcp;
1015 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1016 return -EFAULT;
1017 }
1018 /*
1019 * Check that the context is not smaller than the original
1020 * size (with VMX but without VSX)
1021 */
1022 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1023 return -EINVAL;
1024 /*
1025 * If the new context state sets the MSR VSX bits but
1026 * it doesn't provide VSX state.
1027 */
1028 if ((ctx_size < sizeof(struct ucontext)) &&
1029 (new_msr & MSR_VSX))
1030 return -EINVAL;
1031 /* Does the context have enough room to store VSX data? */
1032 if (ctx_size >= sizeof(struct ucontext))
1033 ctx_has_vsx_region = 1;
1034#else
1035 /* Context size is for future use. Right now, we only make sure
1036 * we are passed something we understand
1037 */
1038 if (ctx_size < sizeof(struct ucontext))
1039 return -EINVAL;
1040#endif
1041 if (old_ctx != NULL) {
1042 struct mcontext __user *mctx;
1043
1044 /*
1045 * old_ctx might not be 16-byte aligned, in which
1046 * case old_ctx->uc_mcontext won't be either.
1047 * Because we have the old_ctx->uc_pad2 field
1048 * before old_ctx->uc_mcontext, we need to round down
1049 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1050 */
1051 mctx = (struct mcontext __user *)
1052 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1053 prepare_save_user_regs(ctx_has_vsx_region);
1054 if (!user_write_access_begin(old_ctx, ctx_size))
1055 return -EFAULT;
1056 unsafe_save_user_regs(regs, mctx, NULL, ctx_has_vsx_region, failed);
1057 unsafe_put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked, failed);
1058 unsafe_put_user(to_user_ptr(mctx), &old_ctx->uc_regs, failed);
1059 user_write_access_end();
1060 }
1061 if (new_ctx == NULL)
1062 return 0;
1063 if (!access_ok(new_ctx, ctx_size) ||
1064 fault_in_readable((char __user *)new_ctx, ctx_size))
1065 return -EFAULT;
1066
1067 /*
1068 * If we get a fault copying the context into the kernel's
1069 * image of the user's registers, we can't just return -EFAULT
1070 * because the user's registers will be corrupted. For instance
1071 * the NIP value may have been updated but not some of the
1072 * other registers. Given that we have done the access_ok
1073 * and successfully read the first and last bytes of the region
1074 * above, this should only happen in an out-of-memory situation
1075 * or if another thread unmaps the region containing the context.
1076 * We kill the task with a SIGSEGV in this situation.
1077 */
1078 if (do_setcontext(new_ctx, regs, 0)) {
1079 force_exit_sig(SIGSEGV);
1080 return -EFAULT;
1081 }
1082
1083 set_thread_flag(TIF_RESTOREALL);
1084 return 0;
1085
1086failed:
1087 user_write_access_end();
1088 return -EFAULT;
1089}
1090
1091#ifdef CONFIG_PPC64
1092COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
1093#else
1094SYSCALL_DEFINE0(rt_sigreturn)
1095#endif
1096{
1097 struct rt_sigframe __user *rt_sf;
1098 struct pt_regs *regs = current_pt_regs();
1099 int tm_restore = 0;
1100#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1101 struct ucontext __user *uc_transact;
1102 unsigned long msr_hi;
1103 unsigned long tmp;
1104#endif
1105 /* Always make any pending restarted system calls return -EINTR */
1106 current->restart_block.fn = do_no_restart_syscall;
1107
1108 rt_sf = (struct rt_sigframe __user *)
1109 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1110 if (!access_ok(rt_sf, sizeof(*rt_sf)))
1111 goto bad;
1112
1113#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1114 /*
1115 * If there is a transactional state then throw it away.
1116 * The purpose of a sigreturn is to destroy all traces of the
1117 * signal frame, this includes any transactional state created
1118 * within in. We only check for suspended as we can never be
1119 * active in the kernel, we are active, there is nothing better to
1120 * do than go ahead and Bad Thing later.
1121 * The cause is not important as there will never be a
1122 * recheckpoint so it's not user visible.
1123 */
1124 if (MSR_TM_SUSPENDED(mfmsr()))
1125 tm_reclaim_current(0);
1126
1127 if (__get_user(tmp, &rt_sf->uc.uc_link))
1128 goto bad;
1129 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1130 if (uc_transact) {
1131 u32 cmcp;
1132 struct mcontext __user *mcp;
1133
1134 if (__get_user(cmcp, &uc_transact->uc_regs))
1135 return -EFAULT;
1136 mcp = (struct mcontext __user *)(u64)cmcp;
1137 /* The top 32 bits of the MSR are stashed in the transactional
1138 * ucontext. */
1139 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1140 goto bad;
1141
1142 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1143 /* Trying to start TM on non TM system */
1144 if (!cpu_has_feature(CPU_FTR_TM))
1145 goto bad;
1146 /* We only recheckpoint on return if we're
1147 * transaction.
1148 */
1149 tm_restore = 1;
1150 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1151 goto bad;
1152 }
1153 }
1154 if (!tm_restore) {
1155 /*
1156 * Unset regs->msr because ucontext MSR TS is not
1157 * set, and recheckpoint was not called. This avoid
1158 * hitting a TM Bad thing at RFID
1159 */
1160 regs_set_return_msr(regs, regs->msr & ~MSR_TS_MASK);
1161 }
1162 /* Fall through, for non-TM restore */
1163#endif
1164 if (!tm_restore)
1165 if (do_setcontext(&rt_sf->uc, regs, 1))
1166 goto bad;
1167
1168 /*
1169 * It's not clear whether or why it is desirable to save the
1170 * sigaltstack setting on signal delivery and restore it on
1171 * signal return. But other architectures do this and we have
1172 * always done it up until now so it is probably better not to
1173 * change it. -- paulus
1174 */
1175#ifdef CONFIG_PPC64
1176 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1177 goto bad;
1178#else
1179 if (restore_altstack(&rt_sf->uc.uc_stack))
1180 goto bad;
1181#endif
1182 set_thread_flag(TIF_RESTOREALL);
1183 return 0;
1184
1185 bad:
1186 signal_fault(current, regs, "sys_rt_sigreturn", rt_sf);
1187
1188 force_sig(SIGSEGV);
1189 return 0;
1190}
1191
1192#ifdef CONFIG_PPC32
1193SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
1194 int, ndbg, struct sig_dbg_op __user *, dbg)
1195{
1196 struct pt_regs *regs = current_pt_regs();
1197 struct sig_dbg_op op;
1198 int i;
1199 unsigned long new_msr = regs->msr;
1200#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1201 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1202#endif
1203
1204 for (i=0; i<ndbg; i++) {
1205 if (copy_from_user(&op, dbg + i, sizeof(op)))
1206 return -EFAULT;
1207 switch (op.dbg_type) {
1208 case SIG_DBG_SINGLE_STEPPING:
1209#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1210 if (op.dbg_value) {
1211 new_msr |= MSR_DE;
1212 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1213 } else {
1214 new_dbcr0 &= ~DBCR0_IC;
1215 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1216 current->thread.debug.dbcr1)) {
1217 new_msr &= ~MSR_DE;
1218 new_dbcr0 &= ~DBCR0_IDM;
1219 }
1220 }
1221#else
1222 if (op.dbg_value)
1223 new_msr |= MSR_SE;
1224 else
1225 new_msr &= ~MSR_SE;
1226#endif
1227 break;
1228 case SIG_DBG_BRANCH_TRACING:
1229#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1230 return -EINVAL;
1231#else
1232 if (op.dbg_value)
1233 new_msr |= MSR_BE;
1234 else
1235 new_msr &= ~MSR_BE;
1236#endif
1237 break;
1238
1239 default:
1240 return -EINVAL;
1241 }
1242 }
1243
1244 /* We wait until here to actually install the values in the
1245 registers so if we fail in the above loop, it will not
1246 affect the contents of these registers. After this point,
1247 failure is a problem, anyway, and it's very unlikely unless
1248 the user is really doing something wrong. */
1249 regs_set_return_msr(regs, new_msr);
1250#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1251 current->thread.debug.dbcr0 = new_dbcr0;
1252#endif
1253
1254 if (!access_ok(ctx, sizeof(*ctx)) ||
1255 fault_in_readable((char __user *)ctx, sizeof(*ctx)))
1256 return -EFAULT;
1257
1258 /*
1259 * If we get a fault copying the context into the kernel's
1260 * image of the user's registers, we can't just return -EFAULT
1261 * because the user's registers will be corrupted. For instance
1262 * the NIP value may have been updated but not some of the
1263 * other registers. Given that we have done the access_ok
1264 * and successfully read the first and last bytes of the region
1265 * above, this should only happen in an out-of-memory situation
1266 * or if another thread unmaps the region containing the context.
1267 * We kill the task with a SIGSEGV in this situation.
1268 */
1269 if (do_setcontext(ctx, regs, 1)) {
1270 signal_fault(current, regs, "sys_debug_setcontext", ctx);
1271
1272 force_sig(SIGSEGV);
1273 goto out;
1274 }
1275
1276 /*
1277 * It's not clear whether or why it is desirable to save the
1278 * sigaltstack setting on signal delivery and restore it on
1279 * signal return. But other architectures do this and we have
1280 * always done it up until now so it is probably better not to
1281 * change it. -- paulus
1282 */
1283 restore_altstack(&ctx->uc_stack);
1284
1285 set_thread_flag(TIF_RESTOREALL);
1286 out:
1287 return 0;
1288}
1289#endif
1290
1291/*
1292 * Do a signal return; undo the signal stack.
1293 */
1294#ifdef CONFIG_PPC64
1295COMPAT_SYSCALL_DEFINE0(sigreturn)
1296#else
1297SYSCALL_DEFINE0(sigreturn)
1298#endif
1299{
1300 struct pt_regs *regs = current_pt_regs();
1301 struct sigframe __user *sf;
1302 struct sigcontext __user *sc;
1303 struct sigcontext sigctx;
1304 struct mcontext __user *sr;
1305 sigset_t set;
1306 struct mcontext __user *mcp;
1307 struct mcontext __user *tm_mcp = NULL;
1308 unsigned long long msr_hi = 0;
1309
1310 /* Always make any pending restarted system calls return -EINTR */
1311 current->restart_block.fn = do_no_restart_syscall;
1312
1313 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1314 sc = &sf->sctx;
1315 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1316 goto badframe;
1317
1318#ifdef CONFIG_PPC64
1319 /*
1320 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1321 * unused part of the signal stackframe
1322 */
1323 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1324#else
1325 set.sig[0] = sigctx.oldmask;
1326 set.sig[1] = sigctx._unused[3];
1327#endif
1328 set_current_blocked(&set);
1329
1330 mcp = (struct mcontext __user *)&sf->mctx;
1331#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1332 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1333 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1334 goto badframe;
1335#endif
1336 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1337 if (!cpu_has_feature(CPU_FTR_TM))
1338 goto badframe;
1339 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1340 goto badframe;
1341 } else {
1342 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1343 if (restore_user_regs(regs, sr, 1)) {
1344 signal_fault(current, regs, "sys_sigreturn", sr);
1345
1346 force_sig(SIGSEGV);
1347 return 0;
1348 }
1349 }
1350
1351 set_thread_flag(TIF_RESTOREALL);
1352 return 0;
1353
1354badframe:
1355 signal_fault(current, regs, "sys_sigreturn", sc);
1356
1357 force_sig(SIGSEGV);
1358 return 0;
1359}
1/*
2 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
3 *
4 * PowerPC version
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Copyright (C) 2001 IBM
7 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
9 *
10 * Derived from "arch/i386/kernel/signal.c"
11 * Copyright (C) 1991, 1992 Linus Torvalds
12 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 */
19
20#include <linux/sched.h>
21#include <linux/mm.h>
22#include <linux/smp.h>
23#include <linux/kernel.h>
24#include <linux/signal.h>
25#include <linux/errno.h>
26#include <linux/elf.h>
27#include <linux/ptrace.h>
28#include <linux/ratelimit.h>
29#ifdef CONFIG_PPC64
30#include <linux/syscalls.h>
31#include <linux/compat.h>
32#else
33#include <linux/wait.h>
34#include <linux/unistd.h>
35#include <linux/stddef.h>
36#include <linux/tty.h>
37#include <linux/binfmts.h>
38#endif
39
40#include <asm/uaccess.h>
41#include <asm/cacheflush.h>
42#include <asm/syscalls.h>
43#include <asm/sigcontext.h>
44#include <asm/vdso.h>
45#include <asm/switch_to.h>
46#include <asm/tm.h>
47#ifdef CONFIG_PPC64
48#include "ppc32.h"
49#include <asm/unistd.h>
50#else
51#include <asm/ucontext.h>
52#include <asm/pgtable.h>
53#endif
54
55#include "signal.h"
56
57
58#ifdef CONFIG_PPC64
59#define sys_rt_sigreturn compat_sys_rt_sigreturn
60#define sys_swapcontext compat_sys_swapcontext
61#define sys_sigreturn compat_sys_sigreturn
62
63#define old_sigaction old_sigaction32
64#define sigcontext sigcontext32
65#define mcontext mcontext32
66#define ucontext ucontext32
67
68#define __save_altstack __compat_save_altstack
69
70/*
71 * Userspace code may pass a ucontext which doesn't include VSX added
72 * at the end. We need to check for this case.
73 */
74#define UCONTEXTSIZEWITHOUTVSX \
75 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32))
76
77/*
78 * Returning 0 means we return to userspace via
79 * ret_from_except and thus restore all user
80 * registers from *regs. This is what we need
81 * to do when a signal has been delivered.
82 */
83
84#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
85#undef __SIGNAL_FRAMESIZE
86#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32
87#undef ELF_NVRREG
88#define ELF_NVRREG ELF_NVRREG32
89
90/*
91 * Functions for flipping sigsets (thanks to brain dead generic
92 * implementation that makes things simple for little endian only)
93 */
94static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
95{
96 compat_sigset_t cset;
97
98 switch (_NSIG_WORDS) {
99 case 4: cset.sig[6] = set->sig[3] & 0xffffffffull;
100 cset.sig[7] = set->sig[3] >> 32;
101 case 3: cset.sig[4] = set->sig[2] & 0xffffffffull;
102 cset.sig[5] = set->sig[2] >> 32;
103 case 2: cset.sig[2] = set->sig[1] & 0xffffffffull;
104 cset.sig[3] = set->sig[1] >> 32;
105 case 1: cset.sig[0] = set->sig[0] & 0xffffffffull;
106 cset.sig[1] = set->sig[0] >> 32;
107 }
108 return copy_to_user(uset, &cset, sizeof(*uset));
109}
110
111static inline int get_sigset_t(sigset_t *set,
112 const compat_sigset_t __user *uset)
113{
114 compat_sigset_t s32;
115
116 if (copy_from_user(&s32, uset, sizeof(*uset)))
117 return -EFAULT;
118
119 /*
120 * Swap the 2 words of the 64-bit sigset_t (they are stored
121 * in the "wrong" endian in 32-bit user storage).
122 */
123 switch (_NSIG_WORDS) {
124 case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
125 case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
126 case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
127 case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
128 }
129 return 0;
130}
131
132#define to_user_ptr(p) ptr_to_compat(p)
133#define from_user_ptr(p) compat_ptr(p)
134
135static inline int save_general_regs(struct pt_regs *regs,
136 struct mcontext __user *frame)
137{
138 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
139 int i;
140
141 WARN_ON(!FULL_REGS(regs));
142
143 for (i = 0; i <= PT_RESULT; i ++) {
144 if (i == 14 && !FULL_REGS(regs))
145 i = 32;
146 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
147 return -EFAULT;
148 }
149 return 0;
150}
151
152static inline int restore_general_regs(struct pt_regs *regs,
153 struct mcontext __user *sr)
154{
155 elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
156 int i;
157
158 for (i = 0; i <= PT_RESULT; i++) {
159 if ((i == PT_MSR) || (i == PT_SOFTE))
160 continue;
161 if (__get_user(gregs[i], &sr->mc_gregs[i]))
162 return -EFAULT;
163 }
164 return 0;
165}
166
167#else /* CONFIG_PPC64 */
168
169#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
170
171static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
172{
173 return copy_to_user(uset, set, sizeof(*uset));
174}
175
176static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
177{
178 return copy_from_user(set, uset, sizeof(*uset));
179}
180
181#define to_user_ptr(p) ((unsigned long)(p))
182#define from_user_ptr(p) ((void __user *)(p))
183
184static inline int save_general_regs(struct pt_regs *regs,
185 struct mcontext __user *frame)
186{
187 WARN_ON(!FULL_REGS(regs));
188 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
189}
190
191static inline int restore_general_regs(struct pt_regs *regs,
192 struct mcontext __user *sr)
193{
194 /* copy up to but not including MSR */
195 if (__copy_from_user(regs, &sr->mc_gregs,
196 PT_MSR * sizeof(elf_greg_t)))
197 return -EFAULT;
198 /* copy from orig_r3 (the word after the MSR) up to the end */
199 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
200 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
201 return -EFAULT;
202 return 0;
203}
204#endif
205
206/*
207 * When we have signals to deliver, we set up on the
208 * user stack, going down from the original stack pointer:
209 * an ABI gap of 56 words
210 * an mcontext struct
211 * a sigcontext struct
212 * a gap of __SIGNAL_FRAMESIZE bytes
213 *
214 * Each of these things must be a multiple of 16 bytes in size. The following
215 * structure represent all of this except the __SIGNAL_FRAMESIZE gap
216 *
217 */
218struct sigframe {
219 struct sigcontext sctx; /* the sigcontext */
220 struct mcontext mctx; /* all the register values */
221#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
222 struct sigcontext sctx_transact;
223 struct mcontext mctx_transact;
224#endif
225 /*
226 * Programs using the rs6000/xcoff abi can save up to 19 gp
227 * regs and 18 fp regs below sp before decrementing it.
228 */
229 int abigap[56];
230};
231
232/* We use the mc_pad field for the signal return trampoline. */
233#define tramp mc_pad
234
235/*
236 * When we have rt signals to deliver, we set up on the
237 * user stack, going down from the original stack pointer:
238 * one rt_sigframe struct (siginfo + ucontext + ABI gap)
239 * a gap of __SIGNAL_FRAMESIZE+16 bytes
240 * (the +16 is to get the siginfo and ucontext in the same
241 * positions as in older kernels).
242 *
243 * Each of these things must be a multiple of 16 bytes in size.
244 *
245 */
246struct rt_sigframe {
247#ifdef CONFIG_PPC64
248 compat_siginfo_t info;
249#else
250 struct siginfo info;
251#endif
252 struct ucontext uc;
253#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
254 struct ucontext uc_transact;
255#endif
256 /*
257 * Programs using the rs6000/xcoff abi can save up to 19 gp
258 * regs and 18 fp regs below sp before decrementing it.
259 */
260 int abigap[56];
261};
262
263#ifdef CONFIG_VSX
264unsigned long copy_fpr_to_user(void __user *to,
265 struct task_struct *task)
266{
267 u64 buf[ELF_NFPREG];
268 int i;
269
270 /* save FPR copy to local buffer then write to the thread_struct */
271 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
272 buf[i] = task->thread.TS_FPR(i);
273 buf[i] = task->thread.fp_state.fpscr;
274 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
275}
276
277unsigned long copy_fpr_from_user(struct task_struct *task,
278 void __user *from)
279{
280 u64 buf[ELF_NFPREG];
281 int i;
282
283 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
284 return 1;
285 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
286 task->thread.TS_FPR(i) = buf[i];
287 task->thread.fp_state.fpscr = buf[i];
288
289 return 0;
290}
291
292unsigned long copy_vsx_to_user(void __user *to,
293 struct task_struct *task)
294{
295 u64 buf[ELF_NVSRHALFREG];
296 int i;
297
298 /* save FPR copy to local buffer then write to the thread_struct */
299 for (i = 0; i < ELF_NVSRHALFREG; i++)
300 buf[i] = task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
301 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
302}
303
304unsigned long copy_vsx_from_user(struct task_struct *task,
305 void __user *from)
306{
307 u64 buf[ELF_NVSRHALFREG];
308 int i;
309
310 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
311 return 1;
312 for (i = 0; i < ELF_NVSRHALFREG ; i++)
313 task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
314 return 0;
315}
316
317#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
318unsigned long copy_transact_fpr_to_user(void __user *to,
319 struct task_struct *task)
320{
321 u64 buf[ELF_NFPREG];
322 int i;
323
324 /* save FPR copy to local buffer then write to the thread_struct */
325 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
326 buf[i] = task->thread.TS_TRANS_FPR(i);
327 buf[i] = task->thread.transact_fp.fpscr;
328 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
329}
330
331unsigned long copy_transact_fpr_from_user(struct task_struct *task,
332 void __user *from)
333{
334 u64 buf[ELF_NFPREG];
335 int i;
336
337 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
338 return 1;
339 for (i = 0; i < (ELF_NFPREG - 1) ; i++)
340 task->thread.TS_TRANS_FPR(i) = buf[i];
341 task->thread.transact_fp.fpscr = buf[i];
342
343 return 0;
344}
345
346unsigned long copy_transact_vsx_to_user(void __user *to,
347 struct task_struct *task)
348{
349 u64 buf[ELF_NVSRHALFREG];
350 int i;
351
352 /* save FPR copy to local buffer then write to the thread_struct */
353 for (i = 0; i < ELF_NVSRHALFREG; i++)
354 buf[i] = task->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET];
355 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
356}
357
358unsigned long copy_transact_vsx_from_user(struct task_struct *task,
359 void __user *from)
360{
361 u64 buf[ELF_NVSRHALFREG];
362 int i;
363
364 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
365 return 1;
366 for (i = 0; i < ELF_NVSRHALFREG ; i++)
367 task->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = buf[i];
368 return 0;
369}
370#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
371#else
372inline unsigned long copy_fpr_to_user(void __user *to,
373 struct task_struct *task)
374{
375 return __copy_to_user(to, task->thread.fp_state.fpr,
376 ELF_NFPREG * sizeof(double));
377}
378
379inline unsigned long copy_fpr_from_user(struct task_struct *task,
380 void __user *from)
381{
382 return __copy_from_user(task->thread.fp_state.fpr, from,
383 ELF_NFPREG * sizeof(double));
384}
385
386#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
387inline unsigned long copy_transact_fpr_to_user(void __user *to,
388 struct task_struct *task)
389{
390 return __copy_to_user(to, task->thread.transact_fp.fpr,
391 ELF_NFPREG * sizeof(double));
392}
393
394inline unsigned long copy_transact_fpr_from_user(struct task_struct *task,
395 void __user *from)
396{
397 return __copy_from_user(task->thread.transact_fp.fpr, from,
398 ELF_NFPREG * sizeof(double));
399}
400#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
401#endif
402
403/*
404 * Save the current user registers on the user stack.
405 * We only save the altivec/spe registers if the process has used
406 * altivec/spe instructions at some point.
407 */
408static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
409 struct mcontext __user *tm_frame, int sigret,
410 int ctx_has_vsx_region)
411{
412 unsigned long msr = regs->msr;
413
414 /* Make sure floating point registers are stored in regs */
415 flush_fp_to_thread(current);
416
417 /* save general registers */
418 if (save_general_regs(regs, frame))
419 return 1;
420
421#ifdef CONFIG_ALTIVEC
422 /* save altivec registers */
423 if (current->thread.used_vr) {
424 flush_altivec_to_thread(current);
425 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
426 ELF_NVRREG * sizeof(vector128)))
427 return 1;
428 /* set MSR_VEC in the saved MSR value to indicate that
429 frame->mc_vregs contains valid data */
430 msr |= MSR_VEC;
431 }
432 /* else assert((regs->msr & MSR_VEC) == 0) */
433
434 /* We always copy to/from vrsave, it's 0 if we don't have or don't
435 * use altivec. Since VSCR only contains 32 bits saved in the least
436 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
437 * most significant bits of that same vector. --BenH
438 * Note that the current VRSAVE value is in the SPR at this point.
439 */
440 if (cpu_has_feature(CPU_FTR_ALTIVEC))
441 current->thread.vrsave = mfspr(SPRN_VRSAVE);
442 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
443 return 1;
444#endif /* CONFIG_ALTIVEC */
445 if (copy_fpr_to_user(&frame->mc_fregs, current))
446 return 1;
447
448 /*
449 * Clear the MSR VSX bit to indicate there is no valid state attached
450 * to this context, except in the specific case below where we set it.
451 */
452 msr &= ~MSR_VSX;
453#ifdef CONFIG_VSX
454 /*
455 * Copy VSR 0-31 upper half from thread_struct to local
456 * buffer, then write that to userspace. Also set MSR_VSX in
457 * the saved MSR value to indicate that frame->mc_vregs
458 * contains valid data
459 */
460 if (current->thread.used_vsr && ctx_has_vsx_region) {
461 flush_vsx_to_thread(current);
462 if (copy_vsx_to_user(&frame->mc_vsregs, current))
463 return 1;
464 msr |= MSR_VSX;
465 }
466#endif /* CONFIG_VSX */
467#ifdef CONFIG_SPE
468 /* save spe registers */
469 if (current->thread.used_spe) {
470 flush_spe_to_thread(current);
471 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
472 ELF_NEVRREG * sizeof(u32)))
473 return 1;
474 /* set MSR_SPE in the saved MSR value to indicate that
475 frame->mc_vregs contains valid data */
476 msr |= MSR_SPE;
477 }
478 /* else assert((regs->msr & MSR_SPE) == 0) */
479
480 /* We always copy to/from spefscr */
481 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
482 return 1;
483#endif /* CONFIG_SPE */
484
485 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
486 return 1;
487 /* We need to write 0 the MSR top 32 bits in the tm frame so that we
488 * can check it on the restore to see if TM is active
489 */
490 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
491 return 1;
492
493 if (sigret) {
494 /* Set up the sigreturn trampoline: li r0,sigret; sc */
495 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
496 || __put_user(0x44000002UL, &frame->tramp[1]))
497 return 1;
498 flush_icache_range((unsigned long) &frame->tramp[0],
499 (unsigned long) &frame->tramp[2]);
500 }
501
502 return 0;
503}
504
505#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
506/*
507 * Save the current user registers on the user stack.
508 * We only save the altivec/spe registers if the process has used
509 * altivec/spe instructions at some point.
510 * We also save the transactional registers to a second ucontext in the
511 * frame.
512 *
513 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
514 */
515static int save_tm_user_regs(struct pt_regs *regs,
516 struct mcontext __user *frame,
517 struct mcontext __user *tm_frame, int sigret)
518{
519 unsigned long msr = regs->msr;
520
521 /* Remove TM bits from thread's MSR. The MSR in the sigcontext
522 * just indicates to userland that we were doing a transaction, but we
523 * don't want to return in transactional state. This also ensures
524 * that flush_fp_to_thread won't set TIF_RESTORE_TM again.
525 */
526 regs->msr &= ~MSR_TS_MASK;
527
528 /* Make sure floating point registers are stored in regs */
529 flush_fp_to_thread(current);
530
531 /* Save both sets of general registers */
532 if (save_general_regs(¤t->thread.ckpt_regs, frame)
533 || save_general_regs(regs, tm_frame))
534 return 1;
535
536 /* Stash the top half of the 64bit MSR into the 32bit MSR word
537 * of the transactional mcontext. This way we have a backward-compatible
538 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
539 * also look at what type of transaction (T or S) was active at the
540 * time of the signal.
541 */
542 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
543 return 1;
544
545#ifdef CONFIG_ALTIVEC
546 /* save altivec registers */
547 if (current->thread.used_vr) {
548 flush_altivec_to_thread(current);
549 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
550 ELF_NVRREG * sizeof(vector128)))
551 return 1;
552 if (msr & MSR_VEC) {
553 if (__copy_to_user(&tm_frame->mc_vregs,
554 ¤t->thread.transact_vr,
555 ELF_NVRREG * sizeof(vector128)))
556 return 1;
557 } else {
558 if (__copy_to_user(&tm_frame->mc_vregs,
559 ¤t->thread.vr_state,
560 ELF_NVRREG * sizeof(vector128)))
561 return 1;
562 }
563
564 /* set MSR_VEC in the saved MSR value to indicate that
565 * frame->mc_vregs contains valid data
566 */
567 msr |= MSR_VEC;
568 }
569
570 /* We always copy to/from vrsave, it's 0 if we don't have or don't
571 * use altivec. Since VSCR only contains 32 bits saved in the least
572 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
573 * most significant bits of that same vector. --BenH
574 */
575 if (cpu_has_feature(CPU_FTR_ALTIVEC))
576 current->thread.vrsave = mfspr(SPRN_VRSAVE);
577 if (__put_user(current->thread.vrsave,
578 (u32 __user *)&frame->mc_vregs[32]))
579 return 1;
580 if (msr & MSR_VEC) {
581 if (__put_user(current->thread.transact_vrsave,
582 (u32 __user *)&tm_frame->mc_vregs[32]))
583 return 1;
584 } else {
585 if (__put_user(current->thread.vrsave,
586 (u32 __user *)&tm_frame->mc_vregs[32]))
587 return 1;
588 }
589#endif /* CONFIG_ALTIVEC */
590
591 if (copy_fpr_to_user(&frame->mc_fregs, current))
592 return 1;
593 if (msr & MSR_FP) {
594 if (copy_transact_fpr_to_user(&tm_frame->mc_fregs, current))
595 return 1;
596 } else {
597 if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
598 return 1;
599 }
600
601#ifdef CONFIG_VSX
602 /*
603 * Copy VSR 0-31 upper half from thread_struct to local
604 * buffer, then write that to userspace. Also set MSR_VSX in
605 * the saved MSR value to indicate that frame->mc_vregs
606 * contains valid data
607 */
608 if (current->thread.used_vsr) {
609 flush_vsx_to_thread(current);
610 if (copy_vsx_to_user(&frame->mc_vsregs, current))
611 return 1;
612 if (msr & MSR_VSX) {
613 if (copy_transact_vsx_to_user(&tm_frame->mc_vsregs,
614 current))
615 return 1;
616 } else {
617 if (copy_vsx_to_user(&tm_frame->mc_vsregs, current))
618 return 1;
619 }
620
621 msr |= MSR_VSX;
622 }
623#endif /* CONFIG_VSX */
624#ifdef CONFIG_SPE
625 /* SPE regs are not checkpointed with TM, so this section is
626 * simply the same as in save_user_regs().
627 */
628 if (current->thread.used_spe) {
629 flush_spe_to_thread(current);
630 if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
631 ELF_NEVRREG * sizeof(u32)))
632 return 1;
633 /* set MSR_SPE in the saved MSR value to indicate that
634 * frame->mc_vregs contains valid data */
635 msr |= MSR_SPE;
636 }
637
638 /* We always copy to/from spefscr */
639 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
640 return 1;
641#endif /* CONFIG_SPE */
642
643 if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
644 return 1;
645 if (sigret) {
646 /* Set up the sigreturn trampoline: li r0,sigret; sc */
647 if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
648 || __put_user(0x44000002UL, &frame->tramp[1]))
649 return 1;
650 flush_icache_range((unsigned long) &frame->tramp[0],
651 (unsigned long) &frame->tramp[2]);
652 }
653
654 return 0;
655}
656#endif
657
658/*
659 * Restore the current user register values from the user stack,
660 * (except for MSR).
661 */
662static long restore_user_regs(struct pt_regs *regs,
663 struct mcontext __user *sr, int sig)
664{
665 long err;
666 unsigned int save_r2 = 0;
667 unsigned long msr;
668#ifdef CONFIG_VSX
669 int i;
670#endif
671
672 /*
673 * restore general registers but not including MSR or SOFTE. Also
674 * take care of keeping r2 (TLS) intact if not a signal
675 */
676 if (!sig)
677 save_r2 = (unsigned int)regs->gpr[2];
678 err = restore_general_regs(regs, sr);
679 regs->trap = 0;
680 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
681 if (!sig)
682 regs->gpr[2] = (unsigned long) save_r2;
683 if (err)
684 return 1;
685
686 /* if doing signal return, restore the previous little-endian mode */
687 if (sig)
688 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
689
690#ifdef CONFIG_ALTIVEC
691 /*
692 * Force the process to reload the altivec registers from
693 * current->thread when it next does altivec instructions
694 */
695 regs->msr &= ~MSR_VEC;
696 if (msr & MSR_VEC) {
697 /* restore altivec registers from the stack */
698 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
699 sizeof(sr->mc_vregs)))
700 return 1;
701 } else if (current->thread.used_vr)
702 memset(¤t->thread.vr_state, 0,
703 ELF_NVRREG * sizeof(vector128));
704
705 /* Always get VRSAVE back */
706 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
707 return 1;
708 if (cpu_has_feature(CPU_FTR_ALTIVEC))
709 mtspr(SPRN_VRSAVE, current->thread.vrsave);
710#endif /* CONFIG_ALTIVEC */
711 if (copy_fpr_from_user(current, &sr->mc_fregs))
712 return 1;
713
714#ifdef CONFIG_VSX
715 /*
716 * Force the process to reload the VSX registers from
717 * current->thread when it next does VSX instruction.
718 */
719 regs->msr &= ~MSR_VSX;
720 if (msr & MSR_VSX) {
721 /*
722 * Restore altivec registers from the stack to a local
723 * buffer, then write this out to the thread_struct
724 */
725 if (copy_vsx_from_user(current, &sr->mc_vsregs))
726 return 1;
727 } else if (current->thread.used_vsr)
728 for (i = 0; i < 32 ; i++)
729 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
730#endif /* CONFIG_VSX */
731 /*
732 * force the process to reload the FP registers from
733 * current->thread when it next does FP instructions
734 */
735 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
736
737#ifdef CONFIG_SPE
738 /* force the process to reload the spe registers from
739 current->thread when it next does spe instructions */
740 regs->msr &= ~MSR_SPE;
741 if (msr & MSR_SPE) {
742 /* restore spe registers from the stack */
743 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
744 ELF_NEVRREG * sizeof(u32)))
745 return 1;
746 } else if (current->thread.used_spe)
747 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
748
749 /* Always get SPEFSCR back */
750 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
751 return 1;
752#endif /* CONFIG_SPE */
753
754 return 0;
755}
756
757#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
758/*
759 * Restore the current user register values from the user stack, except for
760 * MSR, and recheckpoint the original checkpointed register state for processes
761 * in transactions.
762 */
763static long restore_tm_user_regs(struct pt_regs *regs,
764 struct mcontext __user *sr,
765 struct mcontext __user *tm_sr)
766{
767 long err;
768 unsigned long msr, msr_hi;
769#ifdef CONFIG_VSX
770 int i;
771#endif
772
773 /*
774 * restore general registers but not including MSR or SOFTE. Also
775 * take care of keeping r2 (TLS) intact if not a signal.
776 * See comment in signal_64.c:restore_tm_sigcontexts();
777 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
778 * were set by the signal delivery.
779 */
780 err = restore_general_regs(regs, tm_sr);
781 err |= restore_general_regs(¤t->thread.ckpt_regs, sr);
782
783 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
784
785 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
786 if (err)
787 return 1;
788
789 /* Restore the previous little-endian mode */
790 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
791
792#ifdef CONFIG_ALTIVEC
793 regs->msr &= ~MSR_VEC;
794 if (msr & MSR_VEC) {
795 /* restore altivec registers from the stack */
796 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs,
797 sizeof(sr->mc_vregs)) ||
798 __copy_from_user(¤t->thread.transact_vr,
799 &tm_sr->mc_vregs,
800 sizeof(sr->mc_vregs)))
801 return 1;
802 } else if (current->thread.used_vr) {
803 memset(¤t->thread.vr_state, 0,
804 ELF_NVRREG * sizeof(vector128));
805 memset(¤t->thread.transact_vr, 0,
806 ELF_NVRREG * sizeof(vector128));
807 }
808
809 /* Always get VRSAVE back */
810 if (__get_user(current->thread.vrsave,
811 (u32 __user *)&sr->mc_vregs[32]) ||
812 __get_user(current->thread.transact_vrsave,
813 (u32 __user *)&tm_sr->mc_vregs[32]))
814 return 1;
815 if (cpu_has_feature(CPU_FTR_ALTIVEC))
816 mtspr(SPRN_VRSAVE, current->thread.vrsave);
817#endif /* CONFIG_ALTIVEC */
818
819 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
820
821 if (copy_fpr_from_user(current, &sr->mc_fregs) ||
822 copy_transact_fpr_from_user(current, &tm_sr->mc_fregs))
823 return 1;
824
825#ifdef CONFIG_VSX
826 regs->msr &= ~MSR_VSX;
827 if (msr & MSR_VSX) {
828 /*
829 * Restore altivec registers from the stack to a local
830 * buffer, then write this out to the thread_struct
831 */
832 if (copy_vsx_from_user(current, &sr->mc_vsregs) ||
833 copy_transact_vsx_from_user(current, &tm_sr->mc_vsregs))
834 return 1;
835 } else if (current->thread.used_vsr)
836 for (i = 0; i < 32 ; i++) {
837 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
838 current->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = 0;
839 }
840#endif /* CONFIG_VSX */
841
842#ifdef CONFIG_SPE
843 /* SPE regs are not checkpointed with TM, so this section is
844 * simply the same as in restore_user_regs().
845 */
846 regs->msr &= ~MSR_SPE;
847 if (msr & MSR_SPE) {
848 if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
849 ELF_NEVRREG * sizeof(u32)))
850 return 1;
851 } else if (current->thread.used_spe)
852 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
853
854 /* Always get SPEFSCR back */
855 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
856 + ELF_NEVRREG))
857 return 1;
858#endif /* CONFIG_SPE */
859
860 /* Get the top half of the MSR from the user context */
861 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR]))
862 return 1;
863 msr_hi <<= 32;
864 /* If TM bits are set to the reserved value, it's an invalid context */
865 if (MSR_TM_RESV(msr_hi))
866 return 1;
867 /* Pull in the MSR TM bits from the user context */
868 regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr_hi & MSR_TS_MASK);
869 /* Now, recheckpoint. This loads up all of the checkpointed (older)
870 * registers, including FP and V[S]Rs. After recheckpointing, the
871 * transactional versions should be loaded.
872 */
873 tm_enable();
874 /* Make sure the transaction is marked as failed */
875 current->thread.tm_texasr |= TEXASR_FS;
876 /* This loads the checkpointed FP/VEC state, if used */
877 tm_recheckpoint(¤t->thread, msr);
878
879 /* This loads the speculative FP/VEC state, if used */
880 if (msr & MSR_FP) {
881 do_load_up_transact_fpu(¤t->thread);
882 regs->msr |= (MSR_FP | current->thread.fpexc_mode);
883 }
884#ifdef CONFIG_ALTIVEC
885 if (msr & MSR_VEC) {
886 do_load_up_transact_altivec(¤t->thread);
887 regs->msr |= MSR_VEC;
888 }
889#endif
890
891 return 0;
892}
893#endif
894
895#ifdef CONFIG_PPC64
896int copy_siginfo_to_user32(struct compat_siginfo __user *d, const siginfo_t *s)
897{
898 int err;
899
900 if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
901 return -EFAULT;
902
903 /* If you change siginfo_t structure, please be sure
904 * this code is fixed accordingly.
905 * It should never copy any pad contained in the structure
906 * to avoid security leaks, but must copy the generic
907 * 3 ints plus the relevant union member.
908 * This routine must convert siginfo from 64bit to 32bit as well
909 * at the same time.
910 */
911 err = __put_user(s->si_signo, &d->si_signo);
912 err |= __put_user(s->si_errno, &d->si_errno);
913 err |= __put_user((short)s->si_code, &d->si_code);
914 if (s->si_code < 0)
915 err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
916 SI_PAD_SIZE32);
917 else switch(s->si_code >> 16) {
918 case __SI_CHLD >> 16:
919 err |= __put_user(s->si_pid, &d->si_pid);
920 err |= __put_user(s->si_uid, &d->si_uid);
921 err |= __put_user(s->si_utime, &d->si_utime);
922 err |= __put_user(s->si_stime, &d->si_stime);
923 err |= __put_user(s->si_status, &d->si_status);
924 break;
925 case __SI_FAULT >> 16:
926 err |= __put_user((unsigned int)(unsigned long)s->si_addr,
927 &d->si_addr);
928 break;
929 case __SI_POLL >> 16:
930 err |= __put_user(s->si_band, &d->si_band);
931 err |= __put_user(s->si_fd, &d->si_fd);
932 break;
933 case __SI_TIMER >> 16:
934 err |= __put_user(s->si_tid, &d->si_tid);
935 err |= __put_user(s->si_overrun, &d->si_overrun);
936 err |= __put_user(s->si_int, &d->si_int);
937 break;
938 case __SI_SYS >> 16:
939 err |= __put_user(ptr_to_compat(s->si_call_addr), &d->si_call_addr);
940 err |= __put_user(s->si_syscall, &d->si_syscall);
941 err |= __put_user(s->si_arch, &d->si_arch);
942 break;
943 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
944 case __SI_MESGQ >> 16:
945 err |= __put_user(s->si_int, &d->si_int);
946 /* fallthrough */
947 case __SI_KILL >> 16:
948 default:
949 err |= __put_user(s->si_pid, &d->si_pid);
950 err |= __put_user(s->si_uid, &d->si_uid);
951 break;
952 }
953 return err;
954}
955
956#define copy_siginfo_to_user copy_siginfo_to_user32
957
958int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
959{
960 if (copy_from_user(to, from, 3*sizeof(int)) ||
961 copy_from_user(to->_sifields._pad,
962 from->_sifields._pad, SI_PAD_SIZE32))
963 return -EFAULT;
964
965 return 0;
966}
967#endif /* CONFIG_PPC64 */
968
969/*
970 * Set up a signal frame for a "real-time" signal handler
971 * (one which gets siginfo).
972 */
973int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
974 struct pt_regs *regs)
975{
976 struct rt_sigframe __user *rt_sf;
977 struct mcontext __user *frame;
978 struct mcontext __user *tm_frame = NULL;
979 void __user *addr;
980 unsigned long newsp = 0;
981 int sigret;
982 unsigned long tramp;
983
984 /* Set up Signal Frame */
985 /* Put a Real Time Context onto stack */
986 rt_sf = get_sigframe(ksig, get_tm_stackpointer(regs), sizeof(*rt_sf), 1);
987 addr = rt_sf;
988 if (unlikely(rt_sf == NULL))
989 goto badframe;
990
991 /* Put the siginfo & fill in most of the ucontext */
992 if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
993 || __put_user(0, &rt_sf->uc.uc_flags)
994 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
995 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
996 &rt_sf->uc.uc_regs)
997 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
998 goto badframe;
999
1000 /* Save user registers on the stack */
1001 frame = &rt_sf->uc.uc_mcontext;
1002 addr = frame;
1003 if (vdso32_rt_sigtramp && current->mm->context.vdso_base) {
1004 sigret = 0;
1005 tramp = current->mm->context.vdso_base + vdso32_rt_sigtramp;
1006 } else {
1007 sigret = __NR_rt_sigreturn;
1008 tramp = (unsigned long) frame->tramp;
1009 }
1010
1011#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1012 tm_frame = &rt_sf->uc_transact.uc_mcontext;
1013 if (MSR_TM_ACTIVE(regs->msr)) {
1014 if (__put_user((unsigned long)&rt_sf->uc_transact,
1015 &rt_sf->uc.uc_link) ||
1016 __put_user((unsigned long)tm_frame,
1017 &rt_sf->uc_transact.uc_regs))
1018 goto badframe;
1019 if (save_tm_user_regs(regs, frame, tm_frame, sigret))
1020 goto badframe;
1021 }
1022 else
1023#endif
1024 {
1025 if (__put_user(0, &rt_sf->uc.uc_link))
1026 goto badframe;
1027 if (save_user_regs(regs, frame, tm_frame, sigret, 1))
1028 goto badframe;
1029 }
1030 regs->link = tramp;
1031
1032 current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1033
1034 /* create a stack frame for the caller of the handler */
1035 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
1036 addr = (void __user *)regs->gpr[1];
1037 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1038 goto badframe;
1039
1040 /* Fill registers for signal handler */
1041 regs->gpr[1] = newsp;
1042 regs->gpr[3] = ksig->sig;
1043 regs->gpr[4] = (unsigned long) &rt_sf->info;
1044 regs->gpr[5] = (unsigned long) &rt_sf->uc;
1045 regs->gpr[6] = (unsigned long) rt_sf;
1046 regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
1047 /* enter the signal handler in native-endian mode */
1048 regs->msr &= ~MSR_LE;
1049 regs->msr |= (MSR_KERNEL & MSR_LE);
1050 return 0;
1051
1052badframe:
1053 if (show_unhandled_signals)
1054 printk_ratelimited(KERN_INFO
1055 "%s[%d]: bad frame in handle_rt_signal32: "
1056 "%p nip %08lx lr %08lx\n",
1057 current->comm, current->pid,
1058 addr, regs->nip, regs->link);
1059
1060 return 1;
1061}
1062
1063static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
1064{
1065 sigset_t set;
1066 struct mcontext __user *mcp;
1067
1068 if (get_sigset_t(&set, &ucp->uc_sigmask))
1069 return -EFAULT;
1070#ifdef CONFIG_PPC64
1071 {
1072 u32 cmcp;
1073
1074 if (__get_user(cmcp, &ucp->uc_regs))
1075 return -EFAULT;
1076 mcp = (struct mcontext __user *)(u64)cmcp;
1077 /* no need to check access_ok(mcp), since mcp < 4GB */
1078 }
1079#else
1080 if (__get_user(mcp, &ucp->uc_regs))
1081 return -EFAULT;
1082 if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp)))
1083 return -EFAULT;
1084#endif
1085 set_current_blocked(&set);
1086 if (restore_user_regs(regs, mcp, sig))
1087 return -EFAULT;
1088
1089 return 0;
1090}
1091
1092#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1093static int do_setcontext_tm(struct ucontext __user *ucp,
1094 struct ucontext __user *tm_ucp,
1095 struct pt_regs *regs)
1096{
1097 sigset_t set;
1098 struct mcontext __user *mcp;
1099 struct mcontext __user *tm_mcp;
1100 u32 cmcp;
1101 u32 tm_cmcp;
1102
1103 if (get_sigset_t(&set, &ucp->uc_sigmask))
1104 return -EFAULT;
1105
1106 if (__get_user(cmcp, &ucp->uc_regs) ||
1107 __get_user(tm_cmcp, &tm_ucp->uc_regs))
1108 return -EFAULT;
1109 mcp = (struct mcontext __user *)(u64)cmcp;
1110 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
1111 /* no need to check access_ok(mcp), since mcp < 4GB */
1112
1113 set_current_blocked(&set);
1114 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1115 return -EFAULT;
1116
1117 return 0;
1118}
1119#endif
1120
1121long sys_swapcontext(struct ucontext __user *old_ctx,
1122 struct ucontext __user *new_ctx,
1123 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
1124{
1125 unsigned char tmp;
1126 int ctx_has_vsx_region = 0;
1127
1128#ifdef CONFIG_PPC64
1129 unsigned long new_msr = 0;
1130
1131 if (new_ctx) {
1132 struct mcontext __user *mcp;
1133 u32 cmcp;
1134
1135 /*
1136 * Get pointer to the real mcontext. No need for
1137 * access_ok since we are dealing with compat
1138 * pointers.
1139 */
1140 if (__get_user(cmcp, &new_ctx->uc_regs))
1141 return -EFAULT;
1142 mcp = (struct mcontext __user *)(u64)cmcp;
1143 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR]))
1144 return -EFAULT;
1145 }
1146 /*
1147 * Check that the context is not smaller than the original
1148 * size (with VMX but without VSX)
1149 */
1150 if (ctx_size < UCONTEXTSIZEWITHOUTVSX)
1151 return -EINVAL;
1152 /*
1153 * If the new context state sets the MSR VSX bits but
1154 * it doesn't provide VSX state.
1155 */
1156 if ((ctx_size < sizeof(struct ucontext)) &&
1157 (new_msr & MSR_VSX))
1158 return -EINVAL;
1159 /* Does the context have enough room to store VSX data? */
1160 if (ctx_size >= sizeof(struct ucontext))
1161 ctx_has_vsx_region = 1;
1162#else
1163 /* Context size is for future use. Right now, we only make sure
1164 * we are passed something we understand
1165 */
1166 if (ctx_size < sizeof(struct ucontext))
1167 return -EINVAL;
1168#endif
1169 if (old_ctx != NULL) {
1170 struct mcontext __user *mctx;
1171
1172 /*
1173 * old_ctx might not be 16-byte aligned, in which
1174 * case old_ctx->uc_mcontext won't be either.
1175 * Because we have the old_ctx->uc_pad2 field
1176 * before old_ctx->uc_mcontext, we need to round down
1177 * from &old_ctx->uc_mcontext to a 16-byte boundary.
1178 */
1179 mctx = (struct mcontext __user *)
1180 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
1181 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size)
1182 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
1183 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
1184 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
1185 return -EFAULT;
1186 }
1187 if (new_ctx == NULL)
1188 return 0;
1189 if (!access_ok(VERIFY_READ, new_ctx, ctx_size)
1190 || __get_user(tmp, (u8 __user *) new_ctx)
1191 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1))
1192 return -EFAULT;
1193
1194 /*
1195 * If we get a fault copying the context into the kernel's
1196 * image of the user's registers, we can't just return -EFAULT
1197 * because the user's registers will be corrupted. For instance
1198 * the NIP value may have been updated but not some of the
1199 * other registers. Given that we have done the access_ok
1200 * and successfully read the first and last bytes of the region
1201 * above, this should only happen in an out-of-memory situation
1202 * or if another thread unmaps the region containing the context.
1203 * We kill the task with a SIGSEGV in this situation.
1204 */
1205 if (do_setcontext(new_ctx, regs, 0))
1206 do_exit(SIGSEGV);
1207
1208 set_thread_flag(TIF_RESTOREALL);
1209 return 0;
1210}
1211
1212long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1213 struct pt_regs *regs)
1214{
1215 struct rt_sigframe __user *rt_sf;
1216#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1217 struct ucontext __user *uc_transact;
1218 unsigned long msr_hi;
1219 unsigned long tmp;
1220 int tm_restore = 0;
1221#endif
1222 /* Always make any pending restarted system calls return -EINTR */
1223 current->restart_block.fn = do_no_restart_syscall;
1224
1225 rt_sf = (struct rt_sigframe __user *)
1226 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
1227 if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
1228 goto bad;
1229#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1230 if (__get_user(tmp, &rt_sf->uc.uc_link))
1231 goto bad;
1232 uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
1233 if (uc_transact) {
1234 u32 cmcp;
1235 struct mcontext __user *mcp;
1236
1237 if (__get_user(cmcp, &uc_transact->uc_regs))
1238 return -EFAULT;
1239 mcp = (struct mcontext __user *)(u64)cmcp;
1240 /* The top 32 bits of the MSR are stashed in the transactional
1241 * ucontext. */
1242 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
1243 goto bad;
1244
1245 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1246 /* We only recheckpoint on return if we're
1247 * transaction.
1248 */
1249 tm_restore = 1;
1250 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
1251 goto bad;
1252 }
1253 }
1254 if (!tm_restore)
1255 /* Fall through, for non-TM restore */
1256#endif
1257 if (do_setcontext(&rt_sf->uc, regs, 1))
1258 goto bad;
1259
1260 /*
1261 * It's not clear whether or why it is desirable to save the
1262 * sigaltstack setting on signal delivery and restore it on
1263 * signal return. But other architectures do this and we have
1264 * always done it up until now so it is probably better not to
1265 * change it. -- paulus
1266 */
1267#ifdef CONFIG_PPC64
1268 if (compat_restore_altstack(&rt_sf->uc.uc_stack))
1269 goto bad;
1270#else
1271 if (restore_altstack(&rt_sf->uc.uc_stack))
1272 goto bad;
1273#endif
1274 set_thread_flag(TIF_RESTOREALL);
1275 return 0;
1276
1277 bad:
1278 if (show_unhandled_signals)
1279 printk_ratelimited(KERN_INFO
1280 "%s[%d]: bad frame in sys_rt_sigreturn: "
1281 "%p nip %08lx lr %08lx\n",
1282 current->comm, current->pid,
1283 rt_sf, regs->nip, regs->link);
1284
1285 force_sig(SIGSEGV, current);
1286 return 0;
1287}
1288
1289#ifdef CONFIG_PPC32
1290int sys_debug_setcontext(struct ucontext __user *ctx,
1291 int ndbg, struct sig_dbg_op __user *dbg,
1292 int r6, int r7, int r8,
1293 struct pt_regs *regs)
1294{
1295 struct sig_dbg_op op;
1296 int i;
1297 unsigned char tmp;
1298 unsigned long new_msr = regs->msr;
1299#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1300 unsigned long new_dbcr0 = current->thread.debug.dbcr0;
1301#endif
1302
1303 for (i=0; i<ndbg; i++) {
1304 if (copy_from_user(&op, dbg + i, sizeof(op)))
1305 return -EFAULT;
1306 switch (op.dbg_type) {
1307 case SIG_DBG_SINGLE_STEPPING:
1308#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1309 if (op.dbg_value) {
1310 new_msr |= MSR_DE;
1311 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
1312 } else {
1313 new_dbcr0 &= ~DBCR0_IC;
1314 if (!DBCR_ACTIVE_EVENTS(new_dbcr0,
1315 current->thread.debug.dbcr1)) {
1316 new_msr &= ~MSR_DE;
1317 new_dbcr0 &= ~DBCR0_IDM;
1318 }
1319 }
1320#else
1321 if (op.dbg_value)
1322 new_msr |= MSR_SE;
1323 else
1324 new_msr &= ~MSR_SE;
1325#endif
1326 break;
1327 case SIG_DBG_BRANCH_TRACING:
1328#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1329 return -EINVAL;
1330#else
1331 if (op.dbg_value)
1332 new_msr |= MSR_BE;
1333 else
1334 new_msr &= ~MSR_BE;
1335#endif
1336 break;
1337
1338 default:
1339 return -EINVAL;
1340 }
1341 }
1342
1343 /* We wait until here to actually install the values in the
1344 registers so if we fail in the above loop, it will not
1345 affect the contents of these registers. After this point,
1346 failure is a problem, anyway, and it's very unlikely unless
1347 the user is really doing something wrong. */
1348 regs->msr = new_msr;
1349#ifdef CONFIG_PPC_ADV_DEBUG_REGS
1350 current->thread.debug.dbcr0 = new_dbcr0;
1351#endif
1352
1353 if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx))
1354 || __get_user(tmp, (u8 __user *) ctx)
1355 || __get_user(tmp, (u8 __user *) (ctx + 1) - 1))
1356 return -EFAULT;
1357
1358 /*
1359 * If we get a fault copying the context into the kernel's
1360 * image of the user's registers, we can't just return -EFAULT
1361 * because the user's registers will be corrupted. For instance
1362 * the NIP value may have been updated but not some of the
1363 * other registers. Given that we have done the access_ok
1364 * and successfully read the first and last bytes of the region
1365 * above, this should only happen in an out-of-memory situation
1366 * or if another thread unmaps the region containing the context.
1367 * We kill the task with a SIGSEGV in this situation.
1368 */
1369 if (do_setcontext(ctx, regs, 1)) {
1370 if (show_unhandled_signals)
1371 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
1372 "sys_debug_setcontext: %p nip %08lx "
1373 "lr %08lx\n",
1374 current->comm, current->pid,
1375 ctx, regs->nip, regs->link);
1376
1377 force_sig(SIGSEGV, current);
1378 goto out;
1379 }
1380
1381 /*
1382 * It's not clear whether or why it is desirable to save the
1383 * sigaltstack setting on signal delivery and restore it on
1384 * signal return. But other architectures do this and we have
1385 * always done it up until now so it is probably better not to
1386 * change it. -- paulus
1387 */
1388 restore_altstack(&ctx->uc_stack);
1389
1390 set_thread_flag(TIF_RESTOREALL);
1391 out:
1392 return 0;
1393}
1394#endif
1395
1396/*
1397 * OK, we're invoking a handler
1398 */
1399int handle_signal32(struct ksignal *ksig, sigset_t *oldset, struct pt_regs *regs)
1400{
1401 struct sigcontext __user *sc;
1402 struct sigframe __user *frame;
1403 struct mcontext __user *tm_mctx = NULL;
1404 unsigned long newsp = 0;
1405 int sigret;
1406 unsigned long tramp;
1407
1408 /* Set up Signal Frame */
1409 frame = get_sigframe(ksig, get_tm_stackpointer(regs), sizeof(*frame), 1);
1410 if (unlikely(frame == NULL))
1411 goto badframe;
1412 sc = (struct sigcontext __user *) &frame->sctx;
1413
1414#if _NSIG != 64
1415#error "Please adjust handle_signal()"
1416#endif
1417 if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
1418 || __put_user(oldset->sig[0], &sc->oldmask)
1419#ifdef CONFIG_PPC64
1420 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
1421#else
1422 || __put_user(oldset->sig[1], &sc->_unused[3])
1423#endif
1424 || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
1425 || __put_user(ksig->sig, &sc->signal))
1426 goto badframe;
1427
1428 if (vdso32_sigtramp && current->mm->context.vdso_base) {
1429 sigret = 0;
1430 tramp = current->mm->context.vdso_base + vdso32_sigtramp;
1431 } else {
1432 sigret = __NR_sigreturn;
1433 tramp = (unsigned long) frame->mctx.tramp;
1434 }
1435
1436#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1437 tm_mctx = &frame->mctx_transact;
1438 if (MSR_TM_ACTIVE(regs->msr)) {
1439 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
1440 sigret))
1441 goto badframe;
1442 }
1443 else
1444#endif
1445 {
1446 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
1447 goto badframe;
1448 }
1449
1450 regs->link = tramp;
1451
1452 current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
1453
1454 /* create a stack frame for the caller of the handler */
1455 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
1456 if (put_user(regs->gpr[1], (u32 __user *)newsp))
1457 goto badframe;
1458
1459 regs->gpr[1] = newsp;
1460 regs->gpr[3] = ksig->sig;
1461 regs->gpr[4] = (unsigned long) sc;
1462 regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
1463 /* enter the signal handler in big-endian mode */
1464 regs->msr &= ~MSR_LE;
1465 return 0;
1466
1467badframe:
1468 if (show_unhandled_signals)
1469 printk_ratelimited(KERN_INFO
1470 "%s[%d]: bad frame in handle_signal32: "
1471 "%p nip %08lx lr %08lx\n",
1472 current->comm, current->pid,
1473 frame, regs->nip, regs->link);
1474
1475 return 1;
1476}
1477
1478/*
1479 * Do a signal return; undo the signal stack.
1480 */
1481long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
1482 struct pt_regs *regs)
1483{
1484 struct sigframe __user *sf;
1485 struct sigcontext __user *sc;
1486 struct sigcontext sigctx;
1487 struct mcontext __user *sr;
1488 void __user *addr;
1489 sigset_t set;
1490#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1491 struct mcontext __user *mcp, *tm_mcp;
1492 unsigned long msr_hi;
1493#endif
1494
1495 /* Always make any pending restarted system calls return -EINTR */
1496 current->restart_block.fn = do_no_restart_syscall;
1497
1498 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
1499 sc = &sf->sctx;
1500 addr = sc;
1501 if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
1502 goto badframe;
1503
1504#ifdef CONFIG_PPC64
1505 /*
1506 * Note that PPC32 puts the upper 32 bits of the sigmask in the
1507 * unused part of the signal stackframe
1508 */
1509 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
1510#else
1511 set.sig[0] = sigctx.oldmask;
1512 set.sig[1] = sigctx._unused[3];
1513#endif
1514 set_current_blocked(&set);
1515
1516#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1517 mcp = (struct mcontext __user *)&sf->mctx;
1518 tm_mcp = (struct mcontext __user *)&sf->mctx_transact;
1519 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR]))
1520 goto badframe;
1521 if (MSR_TM_ACTIVE(msr_hi<<32)) {
1522 if (!cpu_has_feature(CPU_FTR_TM))
1523 goto badframe;
1524 if (restore_tm_user_regs(regs, mcp, tm_mcp))
1525 goto badframe;
1526 } else
1527#endif
1528 {
1529 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
1530 addr = sr;
1531 if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
1532 || restore_user_regs(regs, sr, 1))
1533 goto badframe;
1534 }
1535
1536 set_thread_flag(TIF_RESTOREALL);
1537 return 0;
1538
1539badframe:
1540 if (show_unhandled_signals)
1541 printk_ratelimited(KERN_INFO
1542 "%s[%d]: bad frame in sys_sigreturn: "
1543 "%p nip %08lx lr %08lx\n",
1544 current->comm, current->pid,
1545 addr, regs->nip, regs->link);
1546
1547 force_sig(SIGSEGV, current);
1548 return 0;
1549}