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