1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Ptrace user space interface.
4 *
5 * Copyright IBM Corp. 1999, 2010
6 * Author(s): Denis Joseph Barrow
7 * Martin Schwidefsky (schwidefsky@de.ibm.com)
8 */
9
10#include "asm/ptrace.h"
11#include <linux/kernel.h>
12#include <linux/sched.h>
13#include <linux/sched/task_stack.h>
14#include <linux/mm.h>
15#include <linux/smp.h>
16#include <linux/errno.h>
17#include <linux/ptrace.h>
18#include <linux/user.h>
19#include <linux/security.h>
20#include <linux/audit.h>
21#include <linux/signal.h>
22#include <linux/elf.h>
23#include <linux/regset.h>
24#include <linux/seccomp.h>
25#include <linux/compat.h>
26#include <trace/syscall.h>
27#include <asm/guarded_storage.h>
28#include <asm/access-regs.h>
29#include <asm/page.h>
30#include <linux/uaccess.h>
31#include <asm/unistd.h>
32#include <asm/runtime_instr.h>
33#include <asm/facility.h>
34#include <asm/fpu.h>
35
36#include "entry.h"
37
38#ifdef CONFIG_COMPAT
39#include "compat_ptrace.h"
40#endif
41
42void update_cr_regs(struct task_struct *task)
43{
44 struct pt_regs *regs = task_pt_regs(task);
45 struct thread_struct *thread = &task->thread;
46 union ctlreg0 cr0_old, cr0_new;
47 union ctlreg2 cr2_old, cr2_new;
48 int cr0_changed, cr2_changed;
49 union {
50 struct ctlreg regs[3];
51 struct {
52 struct ctlreg control;
53 struct ctlreg start;
54 struct ctlreg end;
55 };
56 } old, new;
57
58 local_ctl_store(0, &cr0_old.reg);
59 local_ctl_store(2, &cr2_old.reg);
60 cr0_new = cr0_old;
61 cr2_new = cr2_old;
62 /* Take care of the enable/disable of transactional execution. */
63 if (MACHINE_HAS_TE) {
64 /* Set or clear transaction execution TXC bit 8. */
65 cr0_new.tcx = 1;
66 if (task->thread.per_flags & PER_FLAG_NO_TE)
67 cr0_new.tcx = 0;
68 /* Set or clear transaction execution TDC bits 62 and 63. */
69 cr2_new.tdc = 0;
70 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
71 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
72 cr2_new.tdc = 1;
73 else
74 cr2_new.tdc = 2;
75 }
76 }
77 /* Take care of enable/disable of guarded storage. */
78 if (MACHINE_HAS_GS) {
79 cr2_new.gse = 0;
80 if (task->thread.gs_cb)
81 cr2_new.gse = 1;
82 }
83 /* Load control register 0/2 iff changed */
84 cr0_changed = cr0_new.val != cr0_old.val;
85 cr2_changed = cr2_new.val != cr2_old.val;
86 if (cr0_changed)
87 local_ctl_load(0, &cr0_new.reg);
88 if (cr2_changed)
89 local_ctl_load(2, &cr2_new.reg);
90 /* Copy user specified PER registers */
91 new.control.val = thread->per_user.control;
92 new.start.val = thread->per_user.start;
93 new.end.val = thread->per_user.end;
94
95 /* merge TIF_SINGLE_STEP into user specified PER registers. */
96 if (test_tsk_thread_flag(tsk: task, flag: TIF_SINGLE_STEP) ||
97 test_tsk_thread_flag(tsk: task, flag: TIF_UPROBE_SINGLESTEP)) {
98 if (test_tsk_thread_flag(tsk: task, flag: TIF_BLOCK_STEP))
99 new.control.val |= PER_EVENT_BRANCH;
100 else
101 new.control.val |= PER_EVENT_IFETCH;
102 new.control.val |= PER_CONTROL_SUSPENSION;
103 new.control.val |= PER_EVENT_TRANSACTION_END;
104 if (test_tsk_thread_flag(tsk: task, flag: TIF_UPROBE_SINGLESTEP))
105 new.control.val |= PER_EVENT_IFETCH;
106 new.start.val = 0;
107 new.end.val = -1UL;
108 }
109
110 /* Take care of the PER enablement bit in the PSW. */
111 if (!(new.control.val & PER_EVENT_MASK)) {
112 regs->psw.mask &= ~PSW_MASK_PER;
113 return;
114 }
115 regs->psw.mask |= PSW_MASK_PER;
116 __local_ctl_store(9, 11, old.regs);
117 if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
118 __local_ctl_load(9, 11, new.regs);
119}
120
121void user_enable_single_step(struct task_struct *task)
122{
123 clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
124 set_tsk_thread_flag(task, TIF_SINGLE_STEP);
125}
126
127void user_disable_single_step(struct task_struct *task)
128{
129 clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
130 clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
131}
132
133void user_enable_block_step(struct task_struct *task)
134{
135 set_tsk_thread_flag(task, TIF_SINGLE_STEP);
136 set_tsk_thread_flag(task, TIF_BLOCK_STEP);
137}
138
139/*
140 * Called by kernel/ptrace.c when detaching..
141 *
142 * Clear all debugging related fields.
143 */
144void ptrace_disable(struct task_struct *task)
145{
146 memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
147 memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
148 clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
149 clear_tsk_thread_flag(task, TIF_PER_TRAP);
150 task->thread.per_flags = 0;
151}
152
153#define __ADDR_MASK 7
154
155static inline unsigned long __peek_user_per(struct task_struct *child,
156 addr_t addr)
157{
158 if (addr == offsetof(struct per_struct_kernel, cr9))
159 /* Control bits of the active per set. */
160 return test_thread_flag(TIF_SINGLE_STEP) ?
161 PER_EVENT_IFETCH : child->thread.per_user.control;
162 else if (addr == offsetof(struct per_struct_kernel, cr10))
163 /* Start address of the active per set. */
164 return test_thread_flag(TIF_SINGLE_STEP) ?
165 0 : child->thread.per_user.start;
166 else if (addr == offsetof(struct per_struct_kernel, cr11))
167 /* End address of the active per set. */
168 return test_thread_flag(TIF_SINGLE_STEP) ?
169 -1UL : child->thread.per_user.end;
170 else if (addr == offsetof(struct per_struct_kernel, bits))
171 /* Single-step bit. */
172 return test_thread_flag(TIF_SINGLE_STEP) ?
173 (1UL << (BITS_PER_LONG - 1)) : 0;
174 else if (addr == offsetof(struct per_struct_kernel, starting_addr))
175 /* Start address of the user specified per set. */
176 return child->thread.per_user.start;
177 else if (addr == offsetof(struct per_struct_kernel, ending_addr))
178 /* End address of the user specified per set. */
179 return child->thread.per_user.end;
180 else if (addr == offsetof(struct per_struct_kernel, perc_atmid))
181 /* PER code, ATMID and AI of the last PER trap */
182 return (unsigned long)
183 child->thread.per_event.cause << (BITS_PER_LONG - 16);
184 else if (addr == offsetof(struct per_struct_kernel, address))
185 /* Address of the last PER trap */
186 return child->thread.per_event.address;
187 else if (addr == offsetof(struct per_struct_kernel, access_id))
188 /* Access id of the last PER trap */
189 return (unsigned long)
190 child->thread.per_event.paid << (BITS_PER_LONG - 8);
191 return 0;
192}
193
194/*
195 * Read the word at offset addr from the user area of a process. The
196 * trouble here is that the information is littered over different
197 * locations. The process registers are found on the kernel stack,
198 * the floating point stuff and the trace settings are stored in
199 * the task structure. In addition the different structures in
200 * struct user contain pad bytes that should be read as zeroes.
201 * Lovely...
202 */
203static unsigned long __peek_user(struct task_struct *child, addr_t addr)
204{
205 addr_t offset, tmp;
206
207 if (addr < offsetof(struct user, regs.acrs)) {
208 /*
209 * psw and gprs are stored on the stack
210 */
211 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
212 if (addr == offsetof(struct user, regs.psw.mask)) {
213 /* Return a clean psw mask. */
214 tmp &= PSW_MASK_USER | PSW_MASK_RI;
215 tmp |= PSW_USER_BITS;
216 }
217
218 } else if (addr < offsetof(struct user, regs.orig_gpr2)) {
219 /*
220 * access registers are stored in the thread structure
221 */
222 offset = addr - offsetof(struct user, regs.acrs);
223 /*
224 * Very special case: old & broken 64 bit gdb reading
225 * from acrs[15]. Result is a 64 bit value. Read the
226 * 32 bit acrs[15] value and shift it by 32. Sick...
227 */
228 if (addr == offsetof(struct user, regs.acrs[15]))
229 tmp = ((unsigned long) child->thread.acrs[15]) << 32;
230 else
231 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
232
233 } else if (addr == offsetof(struct user, regs.orig_gpr2)) {
234 /*
235 * orig_gpr2 is stored on the kernel stack
236 */
237 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
238
239 } else if (addr < offsetof(struct user, regs.fp_regs)) {
240 /*
241 * prevent reads of padding hole between
242 * orig_gpr2 and fp_regs on s390.
243 */
244 tmp = 0;
245
246 } else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
247 /*
248 * floating point control reg. is in the thread structure
249 */
250 tmp = child->thread.ufpu.fpc;
251 tmp <<= BITS_PER_LONG - 32;
252
253 } else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
254 /*
255 * floating point regs. are in the child->thread.ufpu.vxrs array
256 */
257 offset = addr - offsetof(struct user, regs.fp_regs.fprs);
258 tmp = *(addr_t *)((addr_t)child->thread.ufpu.vxrs + 2 * offset);
259 } else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
260 /*
261 * Handle access to the per_info structure.
262 */
263 addr -= offsetof(struct user, regs.per_info);
264 tmp = __peek_user_per(child, addr);
265
266 } else
267 tmp = 0;
268
269 return tmp;
270}
271
272static int
273peek_user(struct task_struct *child, addr_t addr, addr_t data)
274{
275 addr_t tmp, mask;
276
277 /*
278 * Stupid gdb peeks/pokes the access registers in 64 bit with
279 * an alignment of 4. Programmers from hell...
280 */
281 mask = __ADDR_MASK;
282 if (addr >= offsetof(struct user, regs.acrs) &&
283 addr < offsetof(struct user, regs.orig_gpr2))
284 mask = 3;
285 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
286 return -EIO;
287
288 tmp = __peek_user(child, addr);
289 return put_user(tmp, (addr_t __user *) data);
290}
291
292static inline void __poke_user_per(struct task_struct *child,
293 addr_t addr, addr_t data)
294{
295 /*
296 * There are only three fields in the per_info struct that the
297 * debugger user can write to.
298 * 1) cr9: the debugger wants to set a new PER event mask
299 * 2) starting_addr: the debugger wants to set a new starting
300 * address to use with the PER event mask.
301 * 3) ending_addr: the debugger wants to set a new ending
302 * address to use with the PER event mask.
303 * The user specified PER event mask and the start and end
304 * addresses are used only if single stepping is not in effect.
305 * Writes to any other field in per_info are ignored.
306 */
307 if (addr == offsetof(struct per_struct_kernel, cr9))
308 /* PER event mask of the user specified per set. */
309 child->thread.per_user.control =
310 data & (PER_EVENT_MASK | PER_CONTROL_MASK);
311 else if (addr == offsetof(struct per_struct_kernel, starting_addr))
312 /* Starting address of the user specified per set. */
313 child->thread.per_user.start = data;
314 else if (addr == offsetof(struct per_struct_kernel, ending_addr))
315 /* Ending address of the user specified per set. */
316 child->thread.per_user.end = data;
317}
318
319/*
320 * Write a word to the user area of a process at location addr. This
321 * operation does have an additional problem compared to peek_user.
322 * Stores to the program status word and on the floating point
323 * control register needs to get checked for validity.
324 */
325static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
326{
327 addr_t offset;
328
329
330 if (addr < offsetof(struct user, regs.acrs)) {
331 struct pt_regs *regs = task_pt_regs(child);
332 /*
333 * psw and gprs are stored on the stack
334 */
335 if (addr == offsetof(struct user, regs.psw.mask)) {
336 unsigned long mask = PSW_MASK_USER;
337
338 mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
339 if ((data ^ PSW_USER_BITS) & ~mask)
340 /* Invalid psw mask. */
341 return -EINVAL;
342 if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
343 /* Invalid address-space-control bits */
344 return -EINVAL;
345 if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
346 /* Invalid addressing mode bits */
347 return -EINVAL;
348 }
349
350 if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
351 addr == offsetof(struct user, regs.gprs[2])) {
352 struct pt_regs *regs = task_pt_regs(child);
353
354 regs->int_code = 0x20000 | (data & 0xffff);
355 }
356 *(addr_t *)((addr_t) &regs->psw + addr) = data;
357 } else if (addr < offsetof(struct user, regs.orig_gpr2)) {
358 /*
359 * access registers are stored in the thread structure
360 */
361 offset = addr - offsetof(struct user, regs.acrs);
362 /*
363 * Very special case: old & broken 64 bit gdb writing
364 * to acrs[15] with a 64 bit value. Ignore the lower
365 * half of the value and write the upper 32 bit to
366 * acrs[15]. Sick...
367 */
368 if (addr == offsetof(struct user, regs.acrs[15]))
369 child->thread.acrs[15] = (unsigned int) (data >> 32);
370 else
371 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
372
373 } else if (addr == offsetof(struct user, regs.orig_gpr2)) {
374 /*
375 * orig_gpr2 is stored on the kernel stack
376 */
377 task_pt_regs(child)->orig_gpr2 = data;
378
379 } else if (addr < offsetof(struct user, regs.fp_regs)) {
380 /*
381 * prevent writes of padding hole between
382 * orig_gpr2 and fp_regs on s390.
383 */
384 return 0;
385
386 } else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
387 /*
388 * floating point control reg. is in the thread structure
389 */
390 if ((unsigned int)data != 0)
391 return -EINVAL;
392 child->thread.ufpu.fpc = data >> (BITS_PER_LONG - 32);
393
394 } else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
395 /*
396 * floating point regs. are in the child->thread.ufpu.vxrs array
397 */
398 offset = addr - offsetof(struct user, regs.fp_regs.fprs);
399 *(addr_t *)((addr_t)child->thread.ufpu.vxrs + 2 * offset) = data;
400 } else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
401 /*
402 * Handle access to the per_info structure.
403 */
404 addr -= offsetof(struct user, regs.per_info);
405 __poke_user_per(child, addr, data);
406
407 }
408
409 return 0;
410}
411
412static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
413{
414 addr_t mask;
415
416 /*
417 * Stupid gdb peeks/pokes the access registers in 64 bit with
418 * an alignment of 4. Programmers from hell indeed...
419 */
420 mask = __ADDR_MASK;
421 if (addr >= offsetof(struct user, regs.acrs) &&
422 addr < offsetof(struct user, regs.orig_gpr2))
423 mask = 3;
424 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
425 return -EIO;
426
427 return __poke_user(child, addr, data);
428}
429
430long arch_ptrace(struct task_struct *child, long request,
431 unsigned long addr, unsigned long data)
432{
433 ptrace_area parea;
434 int copied, ret;
435
436 switch (request) {
437 case PTRACE_PEEKUSR:
438 /* read the word at location addr in the USER area. */
439 return peek_user(child, addr, data);
440
441 case PTRACE_POKEUSR:
442 /* write the word at location addr in the USER area */
443 return poke_user(child, addr, data);
444
445 case PTRACE_PEEKUSR_AREA:
446 case PTRACE_POKEUSR_AREA:
447 if (copy_from_user(&parea, (void __force __user *) addr,
448 sizeof(parea)))
449 return -EFAULT;
450 addr = parea.kernel_addr;
451 data = parea.process_addr;
452 copied = 0;
453 while (copied < parea.len) {
454 if (request == PTRACE_PEEKUSR_AREA)
455 ret = peek_user(child, addr, data);
456 else {
457 addr_t utmp;
458 if (get_user(utmp,
459 (addr_t __force __user *) data))
460 return -EFAULT;
461 ret = poke_user(child, addr, utmp);
462 }
463 if (ret)
464 return ret;
465 addr += sizeof(unsigned long);
466 data += sizeof(unsigned long);
467 copied += sizeof(unsigned long);
468 }
469 return 0;
470 case PTRACE_GET_LAST_BREAK:
471 return put_user(child->thread.last_break, (unsigned long __user *)data);
472 case PTRACE_ENABLE_TE:
473 if (!MACHINE_HAS_TE)
474 return -EIO;
475 child->thread.per_flags &= ~PER_FLAG_NO_TE;
476 return 0;
477 case PTRACE_DISABLE_TE:
478 if (!MACHINE_HAS_TE)
479 return -EIO;
480 child->thread.per_flags |= PER_FLAG_NO_TE;
481 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
482 return 0;
483 case PTRACE_TE_ABORT_RAND:
484 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
485 return -EIO;
486 switch (data) {
487 case 0UL:
488 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
489 break;
490 case 1UL:
491 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
492 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
493 break;
494 case 2UL:
495 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
496 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
497 break;
498 default:
499 return -EINVAL;
500 }
501 return 0;
502 default:
503 return ptrace_request(child, request, addr, data);
504 }
505}
506
507#ifdef CONFIG_COMPAT
508/*
509 * Now the fun part starts... a 31 bit program running in the
510 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
511 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
512 * to handle, the difference to the 64 bit versions of the requests
513 * is that the access is done in multiples of 4 byte instead of
514 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
515 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
516 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
517 * is a 31 bit program too, the content of struct user can be
518 * emulated. A 31 bit program peeking into the struct user of
519 * a 64 bit program is a no-no.
520 */
521
522/*
523 * Same as peek_user_per but for a 31 bit program.
524 */
525static inline __u32 __peek_user_per_compat(struct task_struct *child,
526 addr_t addr)
527{
528 if (addr == offsetof(struct compat_per_struct_kernel, cr9))
529 /* Control bits of the active per set. */
530 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
531 PER_EVENT_IFETCH : child->thread.per_user.control;
532 else if (addr == offsetof(struct compat_per_struct_kernel, cr10))
533 /* Start address of the active per set. */
534 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
535 0 : child->thread.per_user.start;
536 else if (addr == offsetof(struct compat_per_struct_kernel, cr11))
537 /* End address of the active per set. */
538 return test_thread_flag(TIF_SINGLE_STEP) ?
539 PSW32_ADDR_INSN : child->thread.per_user.end;
540 else if (addr == offsetof(struct compat_per_struct_kernel, bits))
541 /* Single-step bit. */
542 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
543 0x80000000 : 0;
544 else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
545 /* Start address of the user specified per set. */
546 return (__u32) child->thread.per_user.start;
547 else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
548 /* End address of the user specified per set. */
549 return (__u32) child->thread.per_user.end;
550 else if (addr == offsetof(struct compat_per_struct_kernel, perc_atmid))
551 /* PER code, ATMID and AI of the last PER trap */
552 return (__u32) child->thread.per_event.cause << 16;
553 else if (addr == offsetof(struct compat_per_struct_kernel, address))
554 /* Address of the last PER trap */
555 return (__u32) child->thread.per_event.address;
556 else if (addr == offsetof(struct compat_per_struct_kernel, access_id))
557 /* Access id of the last PER trap */
558 return (__u32) child->thread.per_event.paid << 24;
559 return 0;
560}
561
562/*
563 * Same as peek_user but for a 31 bit program.
564 */
565static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
566{
567 addr_t offset;
568 __u32 tmp;
569
570 if (addr < offsetof(struct compat_user, regs.acrs)) {
571 struct pt_regs *regs = task_pt_regs(child);
572 /*
573 * psw and gprs are stored on the stack
574 */
575 if (addr == offsetof(struct compat_user, regs.psw.mask)) {
576 /* Fake a 31 bit psw mask. */
577 tmp = (__u32)(regs->psw.mask >> 32);
578 tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
579 tmp |= PSW32_USER_BITS;
580 } else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
581 /* Fake a 31 bit psw address. */
582 tmp = (__u32) regs->psw.addr |
583 (__u32)(regs->psw.mask & PSW_MASK_BA);
584 } else {
585 /* gpr 0-15 */
586 tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
587 }
588 } else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
589 /*
590 * access registers are stored in the thread structure
591 */
592 offset = addr - offsetof(struct compat_user, regs.acrs);
593 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
594
595 } else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
596 /*
597 * orig_gpr2 is stored on the kernel stack
598 */
599 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
600
601 } else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
602 /*
603 * prevent reads of padding hole between
604 * orig_gpr2 and fp_regs on s390.
605 */
606 tmp = 0;
607
608 } else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
609 /*
610 * floating point control reg. is in the thread structure
611 */
612 tmp = child->thread.ufpu.fpc;
613
614 } else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
615 /*
616 * floating point regs. are in the child->thread.ufpu.vxrs array
617 */
618 offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
619 tmp = *(__u32 *)((addr_t)child->thread.ufpu.vxrs + 2 * offset);
620 } else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
621 /*
622 * Handle access to the per_info structure.
623 */
624 addr -= offsetof(struct compat_user, regs.per_info);
625 tmp = __peek_user_per_compat(child, addr);
626
627 } else
628 tmp = 0;
629
630 return tmp;
631}
632
633static int peek_user_compat(struct task_struct *child,
634 addr_t addr, addr_t data)
635{
636 __u32 tmp;
637
638 if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
639 return -EIO;
640
641 tmp = __peek_user_compat(child, addr);
642 return put_user(tmp, (__u32 __user *) data);
643}
644
645/*
646 * Same as poke_user_per but for a 31 bit program.
647 */
648static inline void __poke_user_per_compat(struct task_struct *child,
649 addr_t addr, __u32 data)
650{
651 if (addr == offsetof(struct compat_per_struct_kernel, cr9))
652 /* PER event mask of the user specified per set. */
653 child->thread.per_user.control =
654 data & (PER_EVENT_MASK | PER_CONTROL_MASK);
655 else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
656 /* Starting address of the user specified per set. */
657 child->thread.per_user.start = data;
658 else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
659 /* Ending address of the user specified per set. */
660 child->thread.per_user.end = data;
661}
662
663/*
664 * Same as poke_user but for a 31 bit program.
665 */
666static int __poke_user_compat(struct task_struct *child,
667 addr_t addr, addr_t data)
668{
669 __u32 tmp = (__u32) data;
670 addr_t offset;
671
672 if (addr < offsetof(struct compat_user, regs.acrs)) {
673 struct pt_regs *regs = task_pt_regs(child);
674 /*
675 * psw, gprs, acrs and orig_gpr2 are stored on the stack
676 */
677 if (addr == offsetof(struct compat_user, regs.psw.mask)) {
678 __u32 mask = PSW32_MASK_USER;
679
680 mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
681 /* Build a 64 bit psw mask from 31 bit mask. */
682 if ((tmp ^ PSW32_USER_BITS) & ~mask)
683 /* Invalid psw mask. */
684 return -EINVAL;
685 if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
686 /* Invalid address-space-control bits */
687 return -EINVAL;
688 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
689 (regs->psw.mask & PSW_MASK_BA) |
690 (__u64)(tmp & mask) << 32;
691 } else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
692 /* Build a 64 bit psw address from 31 bit address. */
693 regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
694 /* Transfer 31 bit amode bit to psw mask. */
695 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
696 (__u64)(tmp & PSW32_ADDR_AMODE);
697 } else {
698 if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
699 addr == offsetof(struct compat_user, regs.gprs[2])) {
700 struct pt_regs *regs = task_pt_regs(child);
701
702 regs->int_code = 0x20000 | (data & 0xffff);
703 }
704 /* gpr 0-15 */
705 *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
706 }
707 } else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
708 /*
709 * access registers are stored in the thread structure
710 */
711 offset = addr - offsetof(struct compat_user, regs.acrs);
712 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
713
714 } else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
715 /*
716 * orig_gpr2 is stored on the kernel stack
717 */
718 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
719
720 } else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
721 /*
722 * prevent writess of padding hole between
723 * orig_gpr2 and fp_regs on s390.
724 */
725 return 0;
726
727 } else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
728 /*
729 * floating point control reg. is in the thread structure
730 */
731 child->thread.ufpu.fpc = data;
732
733 } else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
734 /*
735 * floating point regs. are in the child->thread.ufpu.vxrs array
736 */
737 offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
738 *(__u32 *)((addr_t)child->thread.ufpu.vxrs + 2 * offset) = tmp;
739 } else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
740 /*
741 * Handle access to the per_info structure.
742 */
743 addr -= offsetof(struct compat_user, regs.per_info);
744 __poke_user_per_compat(child, addr, data);
745 }
746
747 return 0;
748}
749
750static int poke_user_compat(struct task_struct *child,
751 addr_t addr, addr_t data)
752{
753 if (!is_compat_task() || (addr & 3) ||
754 addr > sizeof(struct compat_user) - 3)
755 return -EIO;
756
757 return __poke_user_compat(child, addr, data);
758}
759
760long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
761 compat_ulong_t caddr, compat_ulong_t cdata)
762{
763 unsigned long addr = caddr;
764 unsigned long data = cdata;
765 compat_ptrace_area parea;
766 int copied, ret;
767
768 switch (request) {
769 case PTRACE_PEEKUSR:
770 /* read the word at location addr in the USER area. */
771 return peek_user_compat(child, addr, data);
772
773 case PTRACE_POKEUSR:
774 /* write the word at location addr in the USER area */
775 return poke_user_compat(child, addr, data);
776
777 case PTRACE_PEEKUSR_AREA:
778 case PTRACE_POKEUSR_AREA:
779 if (copy_from_user(to: &parea, from: (void __force __user *) addr,
780 n: sizeof(parea)))
781 return -EFAULT;
782 addr = parea.kernel_addr;
783 data = parea.process_addr;
784 copied = 0;
785 while (copied < parea.len) {
786 if (request == PTRACE_PEEKUSR_AREA)
787 ret = peek_user_compat(child, addr, data);
788 else {
789 __u32 utmp;
790 if (get_user(utmp,
791 (__u32 __force __user *) data))
792 return -EFAULT;
793 ret = poke_user_compat(child, addr, utmp);
794 }
795 if (ret)
796 return ret;
797 addr += sizeof(unsigned int);
798 data += sizeof(unsigned int);
799 copied += sizeof(unsigned int);
800 }
801 return 0;
802 case PTRACE_GET_LAST_BREAK:
803 return put_user(child->thread.last_break, (unsigned int __user *)data);
804 }
805 return compat_ptrace_request(child, request, addr, data);
806}
807#endif
808
809/*
810 * user_regset definitions.
811 */
812
813static int s390_regs_get(struct task_struct *target,
814 const struct user_regset *regset,
815 struct membuf to)
816{
817 unsigned pos;
818 if (target == current)
819 save_access_regs(target->thread.acrs);
820
821 for (pos = 0; pos < sizeof(s390_regs); pos += sizeof(long))
822 membuf_store(&to, __peek_user(target, pos));
823 return 0;
824}
825
826static int s390_regs_set(struct task_struct *target,
827 const struct user_regset *regset,
828 unsigned int pos, unsigned int count,
829 const void *kbuf, const void __user *ubuf)
830{
831 int rc = 0;
832
833 if (target == current)
834 save_access_regs(target->thread.acrs);
835
836 if (kbuf) {
837 const unsigned long *k = kbuf;
838 while (count > 0 && !rc) {
839 rc = __poke_user(target, pos, *k++);
840 count -= sizeof(*k);
841 pos += sizeof(*k);
842 }
843 } else {
844 const unsigned long __user *u = ubuf;
845 while (count > 0 && !rc) {
846 unsigned long word;
847 rc = __get_user(word, u++);
848 if (rc)
849 break;
850 rc = __poke_user(target, pos, word);
851 count -= sizeof(*u);
852 pos += sizeof(*u);
853 }
854 }
855
856 if (rc == 0 && target == current)
857 restore_access_regs(target->thread.acrs);
858
859 return rc;
860}
861
862static int s390_fpregs_get(struct task_struct *target,
863 const struct user_regset *regset,
864 struct membuf to)
865{
866 _s390_fp_regs fp_regs;
867
868 if (target == current)
869 save_user_fpu_regs();
870
871 fp_regs.fpc = target->thread.ufpu.fpc;
872 fpregs_store(&fp_regs, &target->thread.ufpu);
873
874 return membuf_write(&to, &fp_regs, sizeof(fp_regs));
875}
876
877static int s390_fpregs_set(struct task_struct *target,
878 const struct user_regset *regset, unsigned int pos,
879 unsigned int count, const void *kbuf,
880 const void __user *ubuf)
881{
882 int rc = 0;
883 freg_t fprs[__NUM_FPRS];
884
885 if (target == current)
886 save_user_fpu_regs();
887 convert_vx_to_fp(fprs, target->thread.ufpu.vxrs);
888 if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
889 u32 ufpc[2] = { target->thread.ufpu.fpc, 0 };
890 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
891 0, offsetof(s390_fp_regs, fprs));
892 if (rc)
893 return rc;
894 if (ufpc[1] != 0)
895 return -EINVAL;
896 target->thread.ufpu.fpc = ufpc[0];
897 }
898
899 if (rc == 0 && count > 0)
900 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
901 fprs, offsetof(s390_fp_regs, fprs), -1);
902 if (rc)
903 return rc;
904 convert_fp_to_vx(target->thread.ufpu.vxrs, fprs);
905 return rc;
906}
907
908static int s390_last_break_get(struct task_struct *target,
909 const struct user_regset *regset,
910 struct membuf to)
911{
912 return membuf_store(&to, target->thread.last_break);
913}
914
915static int s390_last_break_set(struct task_struct *target,
916 const struct user_regset *regset,
917 unsigned int pos, unsigned int count,
918 const void *kbuf, const void __user *ubuf)
919{
920 return 0;
921}
922
923static int s390_tdb_get(struct task_struct *target,
924 const struct user_regset *regset,
925 struct membuf to)
926{
927 struct pt_regs *regs = task_pt_regs(target);
928 size_t size;
929
930 if (!(regs->int_code & 0x200))
931 return -ENODATA;
932 size = sizeof(target->thread.trap_tdb.data);
933 return membuf_write(s: &to, v: target->thread.trap_tdb.data, size);
934}
935
936static int s390_tdb_set(struct task_struct *target,
937 const struct user_regset *regset,
938 unsigned int pos, unsigned int count,
939 const void *kbuf, const void __user *ubuf)
940{
941 return 0;
942}
943
944static int s390_vxrs_low_get(struct task_struct *target,
945 const struct user_regset *regset,
946 struct membuf to)
947{
948 __u64 vxrs[__NUM_VXRS_LOW];
949 int i;
950
951 if (!cpu_has_vx())
952 return -ENODEV;
953 if (target == current)
954 save_user_fpu_regs();
955 for (i = 0; i < __NUM_VXRS_LOW; i++)
956 vxrs[i] = target->thread.ufpu.vxrs[i].low;
957 return membuf_write(s: &to, v: vxrs, size: sizeof(vxrs));
958}
959
960static int s390_vxrs_low_set(struct task_struct *target,
961 const struct user_regset *regset,
962 unsigned int pos, unsigned int count,
963 const void *kbuf, const void __user *ubuf)
964{
965 __u64 vxrs[__NUM_VXRS_LOW];
966 int i, rc;
967
968 if (!cpu_has_vx())
969 return -ENODEV;
970 if (target == current)
971 save_user_fpu_regs();
972
973 for (i = 0; i < __NUM_VXRS_LOW; i++)
974 vxrs[i] = target->thread.ufpu.vxrs[i].low;
975
976 rc = user_regset_copyin(pos: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf, data: vxrs, start_pos: 0, end_pos: -1);
977 if (rc == 0)
978 for (i = 0; i < __NUM_VXRS_LOW; i++)
979 target->thread.ufpu.vxrs[i].low = vxrs[i];
980
981 return rc;
982}
983
984static int s390_vxrs_high_get(struct task_struct *target,
985 const struct user_regset *regset,
986 struct membuf to)
987{
988 if (!cpu_has_vx())
989 return -ENODEV;
990 if (target == current)
991 save_user_fpu_regs();
992 return membuf_write(&to, target->thread.ufpu.vxrs + __NUM_VXRS_LOW,
993 __NUM_VXRS_HIGH * sizeof(__vector128));
994}
995
996static int s390_vxrs_high_set(struct task_struct *target,
997 const struct user_regset *regset,
998 unsigned int pos, unsigned int count,
999 const void *kbuf, const void __user *ubuf)
1000{
1001 int rc;
1002
1003 if (!cpu_has_vx())
1004 return -ENODEV;
1005 if (target == current)
1006 save_user_fpu_regs();
1007
1008 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1009 target->thread.ufpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1010 return rc;
1011}
1012
1013static int s390_system_call_get(struct task_struct *target,
1014 const struct user_regset *regset,
1015 struct membuf to)
1016{
1017 return membuf_store(&to, target->thread.system_call);
1018}
1019
1020static int s390_system_call_set(struct task_struct *target,
1021 const struct user_regset *regset,
1022 unsigned int pos, unsigned int count,
1023 const void *kbuf, const void __user *ubuf)
1024{
1025 unsigned int *data = &target->thread.system_call;
1026 return user_regset_copyin(pos: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf,
1027 data, start_pos: 0, end_pos: sizeof(unsigned int));
1028}
1029
1030static int s390_gs_cb_get(struct task_struct *target,
1031 const struct user_regset *regset,
1032 struct membuf to)
1033{
1034 struct gs_cb *data = target->thread.gs_cb;
1035
1036 if (!MACHINE_HAS_GS)
1037 return -ENODEV;
1038 if (!data)
1039 return -ENODATA;
1040 if (target == current)
1041 save_gs_cb(data);
1042 return membuf_write(&to, data, sizeof(struct gs_cb));
1043}
1044
1045static int s390_gs_cb_set(struct task_struct *target,
1046 const struct user_regset *regset,
1047 unsigned int pos, unsigned int count,
1048 const void *kbuf, const void __user *ubuf)
1049{
1050 struct gs_cb gs_cb = { }, *data = NULL;
1051 int rc;
1052
1053 if (!MACHINE_HAS_GS)
1054 return -ENODEV;
1055 if (!target->thread.gs_cb) {
1056 data = kzalloc(sizeof(*data), GFP_KERNEL);
1057 if (!data)
1058 return -ENOMEM;
1059 }
1060 if (!target->thread.gs_cb)
1061 gs_cb.gsd = 25;
1062 else if (target == current)
1063 save_gs_cb(&gs_cb);
1064 else
1065 gs_cb = *target->thread.gs_cb;
1066 rc = user_regset_copyin(pos: &pos, count: &count, kbuf: &kbuf, ubuf: &ubuf,
1067 data: &gs_cb, start_pos: 0, end_pos: sizeof(gs_cb));
1068 if (rc) {
1069 kfree(objp: data);
1070 return -EFAULT;
1071 }
1072 preempt_disable();
1073 if (!target->thread.gs_cb)
1074 target->thread.gs_cb = data;
1075 *target->thread.gs_cb = gs_cb;
1076 if (target == current) {
1077 local_ctl_set_bit(2, CR2_GUARDED_STORAGE_BIT);
1078 restore_gs_cb(target->thread.gs_cb);
1079 }
1080 preempt_enable();
1081 return rc;
1082}
1083
1084static int s390_gs_bc_get(struct task_struct *target,
1085 const struct user_regset *regset,
1086 struct membuf to)
1087{
1088 struct gs_cb *data = target->thread.gs_bc_cb;
1089
1090 if (!MACHINE_HAS_GS)
1091 return -ENODEV;
1092 if (!data)
1093 return -ENODATA;
1094 return membuf_write(&to, data, sizeof(struct gs_cb));
1095}
1096
1097static int s390_gs_bc_set(struct task_struct *target,
1098 const struct user_regset *regset,
1099 unsigned int pos, unsigned int count,
1100 const void *kbuf, const void __user *ubuf)
1101{
1102 struct gs_cb *data = target->thread.gs_bc_cb;
1103
1104 if (!MACHINE_HAS_GS)
1105 return -ENODEV;
1106 if (!data) {
1107 data = kzalloc(sizeof(*data), GFP_KERNEL);
1108 if (!data)
1109 return -ENOMEM;
1110 target->thread.gs_bc_cb = data;
1111 }
1112 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1113 data, 0, sizeof(struct gs_cb));
1114}
1115
1116static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1117{
1118 return (cb->rca & 0x1f) == 0 &&
1119 (cb->roa & 0xfff) == 0 &&
1120 (cb->rla & 0xfff) == 0xfff &&
1121 cb->s == 1 &&
1122 cb->k == 1 &&
1123 cb->h == 0 &&
1124 cb->reserved1 == 0 &&
1125 cb->ps == 1 &&
1126 cb->qs == 0 &&
1127 cb->pc == 1 &&
1128 cb->qc == 0 &&
1129 cb->reserved2 == 0 &&
1130 cb->reserved3 == 0 &&
1131 cb->reserved4 == 0 &&
1132 cb->reserved5 == 0 &&
1133 cb->reserved6 == 0 &&
1134 cb->reserved7 == 0 &&
1135 cb->reserved8 == 0 &&
1136 cb->rla >= cb->roa &&
1137 cb->rca >= cb->roa &&
1138 cb->rca <= cb->rla+1 &&
1139 cb->m < 3;
1140}
1141
1142static int s390_runtime_instr_get(struct task_struct *target,
1143 const struct user_regset *regset,
1144 struct membuf to)
1145{
1146 struct runtime_instr_cb *data = target->thread.ri_cb;
1147
1148 if (!test_facility(64))
1149 return -ENODEV;
1150 if (!data)
1151 return -ENODATA;
1152
1153 return membuf_write(&to, data, sizeof(struct runtime_instr_cb));
1154}
1155
1156static int s390_runtime_instr_set(struct task_struct *target,
1157 const struct user_regset *regset,
1158 unsigned int pos, unsigned int count,
1159 const void *kbuf, const void __user *ubuf)
1160{
1161 struct runtime_instr_cb ri_cb = { }, *data = NULL;
1162 int rc;
1163
1164 if (!test_facility(64))
1165 return -ENODEV;
1166
1167 if (!target->thread.ri_cb) {
1168 data = kzalloc(sizeof(*data), GFP_KERNEL);
1169 if (!data)
1170 return -ENOMEM;
1171 }
1172
1173 if (target->thread.ri_cb) {
1174 if (target == current)
1175 store_runtime_instr_cb(&ri_cb);
1176 else
1177 ri_cb = *target->thread.ri_cb;
1178 }
1179
1180 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1181 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1182 if (rc) {
1183 kfree(objp: data);
1184 return -EFAULT;
1185 }
1186
1187 if (!is_ri_cb_valid(cb: &ri_cb)) {
1188 kfree(objp: data);
1189 return -EINVAL;
1190 }
1191 /*
1192 * Override access key in any case, since user space should
1193 * not be able to set it, nor should it care about it.
1194 */
1195 ri_cb.key = PAGE_DEFAULT_KEY >> 4;
1196 preempt_disable();
1197 if (!target->thread.ri_cb)
1198 target->thread.ri_cb = data;
1199 *target->thread.ri_cb = ri_cb;
1200 if (target == current)
1201 load_runtime_instr_cb(target->thread.ri_cb);
1202 preempt_enable();
1203
1204 return 0;
1205}
1206
1207static const struct user_regset s390_regsets[] = {
1208 {
1209 .core_note_type = NT_PRSTATUS,
1210 .n = sizeof(s390_regs) / sizeof(long),
1211 .size = sizeof(long),
1212 .align = sizeof(long),
1213 .regset_get = s390_regs_get,
1214 .set = s390_regs_set,
1215 },
1216 {
1217 .core_note_type = NT_PRFPREG,
1218 .n = sizeof(s390_fp_regs) / sizeof(long),
1219 .size = sizeof(long),
1220 .align = sizeof(long),
1221 .regset_get = s390_fpregs_get,
1222 .set = s390_fpregs_set,
1223 },
1224 {
1225 .core_note_type = NT_S390_SYSTEM_CALL,
1226 .n = 1,
1227 .size = sizeof(unsigned int),
1228 .align = sizeof(unsigned int),
1229 .regset_get = s390_system_call_get,
1230 .set = s390_system_call_set,
1231 },
1232 {
1233 .core_note_type = NT_S390_LAST_BREAK,
1234 .n = 1,
1235 .size = sizeof(long),
1236 .align = sizeof(long),
1237 .regset_get = s390_last_break_get,
1238 .set = s390_last_break_set,
1239 },
1240 {
1241 .core_note_type = NT_S390_TDB,
1242 .n = 1,
1243 .size = 256,
1244 .align = 1,
1245 .regset_get = s390_tdb_get,
1246 .set = s390_tdb_set,
1247 },
1248 {
1249 .core_note_type = NT_S390_VXRS_LOW,
1250 .n = __NUM_VXRS_LOW,
1251 .size = sizeof(__u64),
1252 .align = sizeof(__u64),
1253 .regset_get = s390_vxrs_low_get,
1254 .set = s390_vxrs_low_set,
1255 },
1256 {
1257 .core_note_type = NT_S390_VXRS_HIGH,
1258 .n = __NUM_VXRS_HIGH,
1259 .size = sizeof(__vector128),
1260 .align = sizeof(__vector128),
1261 .regset_get = s390_vxrs_high_get,
1262 .set = s390_vxrs_high_set,
1263 },
1264 {
1265 .core_note_type = NT_S390_GS_CB,
1266 .n = sizeof(struct gs_cb) / sizeof(__u64),
1267 .size = sizeof(__u64),
1268 .align = sizeof(__u64),
1269 .regset_get = s390_gs_cb_get,
1270 .set = s390_gs_cb_set,
1271 },
1272 {
1273 .core_note_type = NT_S390_GS_BC,
1274 .n = sizeof(struct gs_cb) / sizeof(__u64),
1275 .size = sizeof(__u64),
1276 .align = sizeof(__u64),
1277 .regset_get = s390_gs_bc_get,
1278 .set = s390_gs_bc_set,
1279 },
1280 {
1281 .core_note_type = NT_S390_RI_CB,
1282 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1283 .size = sizeof(__u64),
1284 .align = sizeof(__u64),
1285 .regset_get = s390_runtime_instr_get,
1286 .set = s390_runtime_instr_set,
1287 },
1288};
1289
1290static const struct user_regset_view user_s390_view = {
1291 .name = "s390x",
1292 .e_machine = EM_S390,
1293 .regsets = s390_regsets,
1294 .n = ARRAY_SIZE(s390_regsets)
1295};
1296
1297#ifdef CONFIG_COMPAT
1298static int s390_compat_regs_get(struct task_struct *target,
1299 const struct user_regset *regset,
1300 struct membuf to)
1301{
1302 unsigned n;
1303
1304 if (target == current)
1305 save_access_regs(target->thread.acrs);
1306
1307 for (n = 0; n < sizeof(s390_compat_regs); n += sizeof(compat_ulong_t))
1308 membuf_store(&to, __peek_user_compat(target, n));
1309 return 0;
1310}
1311
1312static int s390_compat_regs_set(struct task_struct *target,
1313 const struct user_regset *regset,
1314 unsigned int pos, unsigned int count,
1315 const void *kbuf, const void __user *ubuf)
1316{
1317 int rc = 0;
1318
1319 if (target == current)
1320 save_access_regs(target->thread.acrs);
1321
1322 if (kbuf) {
1323 const compat_ulong_t *k = kbuf;
1324 while (count > 0 && !rc) {
1325 rc = __poke_user_compat(target, pos, *k++);
1326 count -= sizeof(*k);
1327 pos += sizeof(*k);
1328 }
1329 } else {
1330 const compat_ulong_t __user *u = ubuf;
1331 while (count > 0 && !rc) {
1332 compat_ulong_t word;
1333 rc = __get_user(word, u++);
1334 if (rc)
1335 break;
1336 rc = __poke_user_compat(target, pos, word);
1337 count -= sizeof(*u);
1338 pos += sizeof(*u);
1339 }
1340 }
1341
1342 if (rc == 0 && target == current)
1343 restore_access_regs(target->thread.acrs);
1344
1345 return rc;
1346}
1347
1348static int s390_compat_regs_high_get(struct task_struct *target,
1349 const struct user_regset *regset,
1350 struct membuf to)
1351{
1352 compat_ulong_t *gprs_high;
1353 int i;
1354
1355 gprs_high = (compat_ulong_t *)task_pt_regs(target)->gprs;
1356 for (i = 0; i < NUM_GPRS; i++, gprs_high += 2)
1357 membuf_store(&to, *gprs_high);
1358 return 0;
1359}
1360
1361static int s390_compat_regs_high_set(struct task_struct *target,
1362 const struct user_regset *regset,
1363 unsigned int pos, unsigned int count,
1364 const void *kbuf, const void __user *ubuf)
1365{
1366 compat_ulong_t *gprs_high;
1367 int rc = 0;
1368
1369 gprs_high = (compat_ulong_t *)
1370 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1371 if (kbuf) {
1372 const compat_ulong_t *k = kbuf;
1373 while (count > 0) {
1374 *gprs_high = *k++;
1375 *gprs_high += 2;
1376 count -= sizeof(*k);
1377 }
1378 } else {
1379 const compat_ulong_t __user *u = ubuf;
1380 while (count > 0 && !rc) {
1381 unsigned long word;
1382 rc = __get_user(word, u++);
1383 if (rc)
1384 break;
1385 *gprs_high = word;
1386 *gprs_high += 2;
1387 count -= sizeof(*u);
1388 }
1389 }
1390
1391 return rc;
1392}
1393
1394static int s390_compat_last_break_get(struct task_struct *target,
1395 const struct user_regset *regset,
1396 struct membuf to)
1397{
1398 compat_ulong_t last_break = target->thread.last_break;
1399
1400 return membuf_store(&to, (unsigned long)last_break);
1401}
1402
1403static int s390_compat_last_break_set(struct task_struct *target,
1404 const struct user_regset *regset,
1405 unsigned int pos, unsigned int count,
1406 const void *kbuf, const void __user *ubuf)
1407{
1408 return 0;
1409}
1410
1411static const struct user_regset s390_compat_regsets[] = {
1412 {
1413 .core_note_type = NT_PRSTATUS,
1414 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1415 .size = sizeof(compat_long_t),
1416 .align = sizeof(compat_long_t),
1417 .regset_get = s390_compat_regs_get,
1418 .set = s390_compat_regs_set,
1419 },
1420 {
1421 .core_note_type = NT_PRFPREG,
1422 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1423 .size = sizeof(compat_long_t),
1424 .align = sizeof(compat_long_t),
1425 .regset_get = s390_fpregs_get,
1426 .set = s390_fpregs_set,
1427 },
1428 {
1429 .core_note_type = NT_S390_SYSTEM_CALL,
1430 .n = 1,
1431 .size = sizeof(compat_uint_t),
1432 .align = sizeof(compat_uint_t),
1433 .regset_get = s390_system_call_get,
1434 .set = s390_system_call_set,
1435 },
1436 {
1437 .core_note_type = NT_S390_LAST_BREAK,
1438 .n = 1,
1439 .size = sizeof(long),
1440 .align = sizeof(long),
1441 .regset_get = s390_compat_last_break_get,
1442 .set = s390_compat_last_break_set,
1443 },
1444 {
1445 .core_note_type = NT_S390_TDB,
1446 .n = 1,
1447 .size = 256,
1448 .align = 1,
1449 .regset_get = s390_tdb_get,
1450 .set = s390_tdb_set,
1451 },
1452 {
1453 .core_note_type = NT_S390_VXRS_LOW,
1454 .n = __NUM_VXRS_LOW,
1455 .size = sizeof(__u64),
1456 .align = sizeof(__u64),
1457 .regset_get = s390_vxrs_low_get,
1458 .set = s390_vxrs_low_set,
1459 },
1460 {
1461 .core_note_type = NT_S390_VXRS_HIGH,
1462 .n = __NUM_VXRS_HIGH,
1463 .size = sizeof(__vector128),
1464 .align = sizeof(__vector128),
1465 .regset_get = s390_vxrs_high_get,
1466 .set = s390_vxrs_high_set,
1467 },
1468 {
1469 .core_note_type = NT_S390_HIGH_GPRS,
1470 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1471 .size = sizeof(compat_long_t),
1472 .align = sizeof(compat_long_t),
1473 .regset_get = s390_compat_regs_high_get,
1474 .set = s390_compat_regs_high_set,
1475 },
1476 {
1477 .core_note_type = NT_S390_GS_CB,
1478 .n = sizeof(struct gs_cb) / sizeof(__u64),
1479 .size = sizeof(__u64),
1480 .align = sizeof(__u64),
1481 .regset_get = s390_gs_cb_get,
1482 .set = s390_gs_cb_set,
1483 },
1484 {
1485 .core_note_type = NT_S390_GS_BC,
1486 .n = sizeof(struct gs_cb) / sizeof(__u64),
1487 .size = sizeof(__u64),
1488 .align = sizeof(__u64),
1489 .regset_get = s390_gs_bc_get,
1490 .set = s390_gs_bc_set,
1491 },
1492 {
1493 .core_note_type = NT_S390_RI_CB,
1494 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1495 .size = sizeof(__u64),
1496 .align = sizeof(__u64),
1497 .regset_get = s390_runtime_instr_get,
1498 .set = s390_runtime_instr_set,
1499 },
1500};
1501
1502static const struct user_regset_view user_s390_compat_view = {
1503 .name = "s390",
1504 .e_machine = EM_S390,
1505 .regsets = s390_compat_regsets,
1506 .n = ARRAY_SIZE(s390_compat_regsets)
1507};
1508#endif
1509
1510const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1511{
1512#ifdef CONFIG_COMPAT
1513 if (test_tsk_thread_flag(task, TIF_31BIT))
1514 return &user_s390_compat_view;
1515#endif
1516 return &user_s390_view;
1517}
1518
1519static const char *gpr_names[NUM_GPRS] = {
1520 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
1521 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1522};
1523
1524unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1525{
1526 if (offset >= NUM_GPRS)
1527 return 0;
1528 return regs->gprs[offset];
1529}
1530
1531int regs_query_register_offset(const char *name)
1532{
1533 unsigned long offset;
1534
1535 if (!name || *name != 'r')
1536 return -EINVAL;
1537 if (kstrtoul(s: name + 1, base: 10, res: &offset))
1538 return -EINVAL;
1539 if (offset >= NUM_GPRS)
1540 return -EINVAL;
1541 return offset;
1542}
1543
1544const char *regs_query_register_name(unsigned int offset)
1545{
1546 if (offset >= NUM_GPRS)
1547 return NULL;
1548 return gpr_names[offset];
1549}
1550
1551static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1552{
1553 unsigned long ksp = kernel_stack_pointer(regs);
1554
1555 return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1556}
1557
1558/**
1559 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1560 * @regs:pt_regs which contains kernel stack pointer.
1561 * @n:stack entry number.
1562 *
1563 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1564 * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1565 * this returns 0.
1566 */
1567unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1568{
1569 unsigned long addr;
1570
1571 addr = kernel_stack_pointer(regs) + n * sizeof(long);
1572 if (!regs_within_kernel_stack(regs, addr))
1573 return 0;
1574 return *(unsigned long *)addr;
1575}
1576

source code of linux/arch/s390/kernel/ptrace.c