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