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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/page.h>
28#include <linux/uaccess.h>
29#include <asm/unistd.h>
30#include <asm/switch_to.h>
31#include <asm/runtime_instr.h>
32#include <asm/facility.h>
33
34#include "entry.h"
35
36#ifdef CONFIG_COMPAT
37#include "compat_ptrace.h"
38#endif
39
40void update_cr_regs(struct task_struct *task)
41{
42 struct pt_regs *regs = task_pt_regs(task);
43 struct thread_struct *thread = &task->thread;
44 struct per_regs old, new;
45 union ctlreg0 cr0_old, cr0_new;
46 union ctlreg2 cr2_old, cr2_new;
47 int cr0_changed, cr2_changed;
48
49 __ctl_store(cr0_old.val, 0, 0);
50 __ctl_store(cr2_old.val, 2, 2);
51 cr0_new = cr0_old;
52 cr2_new = cr2_old;
53 /* Take care of the enable/disable of transactional execution. */
54 if (MACHINE_HAS_TE) {
55 /* Set or clear transaction execution TXC bit 8. */
56 cr0_new.tcx = 1;
57 if (task->thread.per_flags & PER_FLAG_NO_TE)
58 cr0_new.tcx = 0;
59 /* Set or clear transaction execution TDC bits 62 and 63. */
60 cr2_new.tdc = 0;
61 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
62 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
63 cr2_new.tdc = 1;
64 else
65 cr2_new.tdc = 2;
66 }
67 }
68 /* Take care of enable/disable of guarded storage. */
69 if (MACHINE_HAS_GS) {
70 cr2_new.gse = 0;
71 if (task->thread.gs_cb)
72 cr2_new.gse = 1;
73 }
74 /* Load control register 0/2 iff changed */
75 cr0_changed = cr0_new.val != cr0_old.val;
76 cr2_changed = cr2_new.val != cr2_old.val;
77 if (cr0_changed)
78 __ctl_load(cr0_new.val, 0, 0);
79 if (cr2_changed)
80 __ctl_load(cr2_new.val, 2, 2);
81 /* Copy user specified PER registers */
82 new.control = thread->per_user.control;
83 new.start = thread->per_user.start;
84 new.end = thread->per_user.end;
85
86 /* merge TIF_SINGLE_STEP into user specified PER registers. */
87 if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
88 test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
89 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
90 new.control |= PER_EVENT_BRANCH;
91 else
92 new.control |= PER_EVENT_IFETCH;
93 new.control |= PER_CONTROL_SUSPENSION;
94 new.control |= PER_EVENT_TRANSACTION_END;
95 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
96 new.control |= PER_EVENT_IFETCH;
97 new.start = 0;
98 new.end = -1UL;
99 }
100
101 /* Take care of the PER enablement bit in the PSW. */
102 if (!(new.control & PER_EVENT_MASK)) {
103 regs->psw.mask &= ~PSW_MASK_PER;
104 return;
105 }
106 regs->psw.mask |= PSW_MASK_PER;
107 __ctl_store(old, 9, 11);
108 if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
109 __ctl_load(new, 9, 11);
110}
111
112void user_enable_single_step(struct task_struct *task)
113{
114 clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
115 set_tsk_thread_flag(task, TIF_SINGLE_STEP);
116}
117
118void user_disable_single_step(struct task_struct *task)
119{
120 clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
121 clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
122}
123
124void user_enable_block_step(struct task_struct *task)
125{
126 set_tsk_thread_flag(task, TIF_SINGLE_STEP);
127 set_tsk_thread_flag(task, TIF_BLOCK_STEP);
128}
129
130/*
131 * Called by kernel/ptrace.c when detaching..
132 *
133 * Clear all debugging related fields.
134 */
135void ptrace_disable(struct task_struct *task)
136{
137 memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
138 memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
139 clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
140 clear_tsk_thread_flag(task, TIF_PER_TRAP);
141 task->thread.per_flags = 0;
142}
143
144#define __ADDR_MASK 7
145
146static inline unsigned long __peek_user_per(struct task_struct *child,
147 addr_t addr)
148{
149 if (addr == offsetof(struct per_struct_kernel, cr9))
150 /* Control bits of the active per set. */
151 return test_thread_flag(TIF_SINGLE_STEP) ?
152 PER_EVENT_IFETCH : child->thread.per_user.control;
153 else if (addr == offsetof(struct per_struct_kernel, cr10))
154 /* Start address of the active per set. */
155 return test_thread_flag(TIF_SINGLE_STEP) ?
156 0 : child->thread.per_user.start;
157 else if (addr == offsetof(struct per_struct_kernel, cr11))
158 /* End address of the active per set. */
159 return test_thread_flag(TIF_SINGLE_STEP) ?
160 -1UL : child->thread.per_user.end;
161 else if (addr == offsetof(struct per_struct_kernel, bits))
162 /* Single-step bit. */
163 return test_thread_flag(TIF_SINGLE_STEP) ?
164 (1UL << (BITS_PER_LONG - 1)) : 0;
165 else if (addr == offsetof(struct per_struct_kernel, starting_addr))
166 /* Start address of the user specified per set. */
167 return child->thread.per_user.start;
168 else if (addr == offsetof(struct per_struct_kernel, ending_addr))
169 /* End address of the user specified per set. */
170 return child->thread.per_user.end;
171 else if (addr == offsetof(struct per_struct_kernel, perc_atmid))
172 /* PER code, ATMID and AI of the last PER trap */
173 return (unsigned long)
174 child->thread.per_event.cause << (BITS_PER_LONG - 16);
175 else if (addr == offsetof(struct per_struct_kernel, address))
176 /* Address of the last PER trap */
177 return child->thread.per_event.address;
178 else if (addr == offsetof(struct per_struct_kernel, access_id))
179 /* Access id of the last PER trap */
180 return (unsigned long)
181 child->thread.per_event.paid << (BITS_PER_LONG - 8);
182 return 0;
183}
184
185/*
186 * Read the word at offset addr from the user area of a process. The
187 * trouble here is that the information is littered over different
188 * locations. The process registers are found on the kernel stack,
189 * the floating point stuff and the trace settings are stored in
190 * the task structure. In addition the different structures in
191 * struct user contain pad bytes that should be read as zeroes.
192 * Lovely...
193 */
194static unsigned long __peek_user(struct task_struct *child, addr_t addr)
195{
196 addr_t offset, tmp;
197
198 if (addr < offsetof(struct user, regs.acrs)) {
199 /*
200 * psw and gprs are stored on the stack
201 */
202 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
203 if (addr == offsetof(struct user, regs.psw.mask)) {
204 /* Return a clean psw mask. */
205 tmp &= PSW_MASK_USER | PSW_MASK_RI;
206 tmp |= PSW_USER_BITS;
207 }
208
209 } else if (addr < offsetof(struct user, regs.orig_gpr2)) {
210 /*
211 * access registers are stored in the thread structure
212 */
213 offset = addr - offsetof(struct user, regs.acrs);
214 /*
215 * Very special case: old & broken 64 bit gdb reading
216 * from acrs[15]. Result is a 64 bit value. Read the
217 * 32 bit acrs[15] value and shift it by 32. Sick...
218 */
219 if (addr == offsetof(struct user, regs.acrs[15]))
220 tmp = ((unsigned long) child->thread.acrs[15]) << 32;
221 else
222 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
223
224 } else if (addr == offsetof(struct user, regs.orig_gpr2)) {
225 /*
226 * orig_gpr2 is stored on the kernel stack
227 */
228 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
229
230 } else if (addr < offsetof(struct user, regs.fp_regs)) {
231 /*
232 * prevent reads of padding hole between
233 * orig_gpr2 and fp_regs on s390.
234 */
235 tmp = 0;
236
237 } else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
238 /*
239 * floating point control reg. is in the thread structure
240 */
241 tmp = child->thread.fpu.fpc;
242 tmp <<= BITS_PER_LONG - 32;
243
244 } else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
245 /*
246 * floating point regs. are either in child->thread.fpu
247 * or the child->thread.fpu.vxrs array
248 */
249 offset = addr - offsetof(struct user, regs.fp_regs.fprs);
250 if (MACHINE_HAS_VX)
251 tmp = *(addr_t *)
252 ((addr_t) child->thread.fpu.vxrs + 2*offset);
253 else
254 tmp = *(addr_t *)
255 ((addr_t) child->thread.fpu.fprs + offset);
256
257 } else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
258 /*
259 * Handle access to the per_info structure.
260 */
261 addr -= offsetof(struct user, regs.per_info);
262 tmp = __peek_user_per(child, addr);
263
264 } else
265 tmp = 0;
266
267 return tmp;
268}
269
270static int
271peek_user(struct task_struct *child, addr_t addr, addr_t data)
272{
273 addr_t tmp, mask;
274
275 /*
276 * Stupid gdb peeks/pokes the access registers in 64 bit with
277 * an alignment of 4. Programmers from hell...
278 */
279 mask = __ADDR_MASK;
280 if (addr >= offsetof(struct user, regs.acrs) &&
281 addr < offsetof(struct user, regs.orig_gpr2))
282 mask = 3;
283 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
284 return -EIO;
285
286 tmp = __peek_user(child, addr);
287 return put_user(tmp, (addr_t __user *) data);
288}
289
290static inline void __poke_user_per(struct task_struct *child,
291 addr_t addr, addr_t data)
292{
293 /*
294 * There are only three fields in the per_info struct that the
295 * debugger user can write to.
296 * 1) cr9: the debugger wants to set a new PER event mask
297 * 2) starting_addr: the debugger wants to set a new starting
298 * address to use with the PER event mask.
299 * 3) ending_addr: the debugger wants to set a new ending
300 * address to use with the PER event mask.
301 * The user specified PER event mask and the start and end
302 * addresses are used only if single stepping is not in effect.
303 * Writes to any other field in per_info are ignored.
304 */
305 if (addr == offsetof(struct per_struct_kernel, cr9))
306 /* PER event mask of the user specified per set. */
307 child->thread.per_user.control =
308 data & (PER_EVENT_MASK | PER_CONTROL_MASK);
309 else if (addr == offsetof(struct per_struct_kernel, starting_addr))
310 /* Starting address of the user specified per set. */
311 child->thread.per_user.start = data;
312 else if (addr == offsetof(struct per_struct_kernel, ending_addr))
313 /* Ending address of the user specified per set. */
314 child->thread.per_user.end = data;
315}
316
317/*
318 * Write a word to the user area of a process at location addr. This
319 * operation does have an additional problem compared to peek_user.
320 * Stores to the program status word and on the floating point
321 * control register needs to get checked for validity.
322 */
323static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
324{
325 addr_t offset;
326
327
328 if (addr < offsetof(struct user, regs.acrs)) {
329 struct pt_regs *regs = task_pt_regs(child);
330 /*
331 * psw and gprs are stored on the stack
332 */
333 if (addr == offsetof(struct user, regs.psw.mask)) {
334 unsigned long mask = PSW_MASK_USER;
335
336 mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
337 if ((data ^ PSW_USER_BITS) & ~mask)
338 /* Invalid psw mask. */
339 return -EINVAL;
340 if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
341 /* Invalid address-space-control bits */
342 return -EINVAL;
343 if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
344 /* Invalid addressing mode bits */
345 return -EINVAL;
346 }
347
348 if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
349 addr == offsetof(struct user, regs.gprs[2])) {
350 struct pt_regs *regs = task_pt_regs(child);
351
352 regs->int_code = 0x20000 | (data & 0xffff);
353 }
354 *(addr_t *)((addr_t) ®s->psw + addr) = data;
355 } else if (addr < offsetof(struct user, regs.orig_gpr2)) {
356 /*
357 * access registers are stored in the thread structure
358 */
359 offset = addr - offsetof(struct user, regs.acrs);
360 /*
361 * Very special case: old & broken 64 bit gdb writing
362 * to acrs[15] with a 64 bit value. Ignore the lower
363 * half of the value and write the upper 32 bit to
364 * acrs[15]. Sick...
365 */
366 if (addr == offsetof(struct user, regs.acrs[15]))
367 child->thread.acrs[15] = (unsigned int) (data >> 32);
368 else
369 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
370
371 } else if (addr == offsetof(struct user, regs.orig_gpr2)) {
372 /*
373 * orig_gpr2 is stored on the kernel stack
374 */
375 task_pt_regs(child)->orig_gpr2 = data;
376
377 } else if (addr < offsetof(struct user, regs.fp_regs)) {
378 /*
379 * prevent writes of padding hole between
380 * orig_gpr2 and fp_regs on s390.
381 */
382 return 0;
383
384 } else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
385 /*
386 * floating point control reg. is in the thread structure
387 */
388 if ((unsigned int) data != 0 ||
389 test_fp_ctl(data >> (BITS_PER_LONG - 32)))
390 return -EINVAL;
391 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
392
393 } else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
394 /*
395 * floating point regs. are either in child->thread.fpu
396 * or the child->thread.fpu.vxrs array
397 */
398 offset = addr - offsetof(struct user, regs.fp_regs.fprs);
399 if (MACHINE_HAS_VX)
400 *(addr_t *)((addr_t)
401 child->thread.fpu.vxrs + 2*offset) = data;
402 else
403 *(addr_t *)((addr_t)
404 child->thread.fpu.fprs + offset) = data;
405
406 } else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
407 /*
408 * Handle access to the per_info structure.
409 */
410 addr -= offsetof(struct user, regs.per_info);
411 __poke_user_per(child, addr, data);
412
413 }
414
415 return 0;
416}
417
418static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
419{
420 addr_t mask;
421
422 /*
423 * Stupid gdb peeks/pokes the access registers in 64 bit with
424 * an alignment of 4. Programmers from hell indeed...
425 */
426 mask = __ADDR_MASK;
427 if (addr >= offsetof(struct user, regs.acrs) &&
428 addr < offsetof(struct user, regs.orig_gpr2))
429 mask = 3;
430 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
431 return -EIO;
432
433 return __poke_user(child, addr, data);
434}
435
436long arch_ptrace(struct task_struct *child, long request,
437 unsigned long addr, unsigned long data)
438{
439 ptrace_area parea;
440 int copied, ret;
441
442 switch (request) {
443 case PTRACE_PEEKUSR:
444 /* read the word at location addr in the USER area. */
445 return peek_user(child, addr, data);
446
447 case PTRACE_POKEUSR:
448 /* write the word at location addr in the USER area */
449 return poke_user(child, addr, data);
450
451 case PTRACE_PEEKUSR_AREA:
452 case PTRACE_POKEUSR_AREA:
453 if (copy_from_user(&parea, (void __force __user *) addr,
454 sizeof(parea)))
455 return -EFAULT;
456 addr = parea.kernel_addr;
457 data = parea.process_addr;
458 copied = 0;
459 while (copied < parea.len) {
460 if (request == PTRACE_PEEKUSR_AREA)
461 ret = peek_user(child, addr, data);
462 else {
463 addr_t utmp;
464 if (get_user(utmp,
465 (addr_t __force __user *) data))
466 return -EFAULT;
467 ret = poke_user(child, addr, utmp);
468 }
469 if (ret)
470 return ret;
471 addr += sizeof(unsigned long);
472 data += sizeof(unsigned long);
473 copied += sizeof(unsigned long);
474 }
475 return 0;
476 case PTRACE_GET_LAST_BREAK:
477 put_user(child->thread.last_break,
478 (unsigned long __user *) data);
479 return 0;
480 case PTRACE_ENABLE_TE:
481 if (!MACHINE_HAS_TE)
482 return -EIO;
483 child->thread.per_flags &= ~PER_FLAG_NO_TE;
484 return 0;
485 case PTRACE_DISABLE_TE:
486 if (!MACHINE_HAS_TE)
487 return -EIO;
488 child->thread.per_flags |= PER_FLAG_NO_TE;
489 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
490 return 0;
491 case PTRACE_TE_ABORT_RAND:
492 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
493 return -EIO;
494 switch (data) {
495 case 0UL:
496 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
497 break;
498 case 1UL:
499 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
500 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
501 break;
502 case 2UL:
503 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
504 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
505 break;
506 default:
507 return -EINVAL;
508 }
509 return 0;
510 default:
511 return ptrace_request(child, request, addr, data);
512 }
513}
514
515#ifdef CONFIG_COMPAT
516/*
517 * Now the fun part starts... a 31 bit program running in the
518 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
519 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
520 * to handle, the difference to the 64 bit versions of the requests
521 * is that the access is done in multiples of 4 byte instead of
522 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
523 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
524 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
525 * is a 31 bit program too, the content of struct user can be
526 * emulated. A 31 bit program peeking into the struct user of
527 * a 64 bit program is a no-no.
528 */
529
530/*
531 * Same as peek_user_per but for a 31 bit program.
532 */
533static inline __u32 __peek_user_per_compat(struct task_struct *child,
534 addr_t addr)
535{
536 if (addr == offsetof(struct compat_per_struct_kernel, cr9))
537 /* Control bits of the active per set. */
538 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
539 PER_EVENT_IFETCH : child->thread.per_user.control;
540 else if (addr == offsetof(struct compat_per_struct_kernel, cr10))
541 /* Start address of the active per set. */
542 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
543 0 : child->thread.per_user.start;
544 else if (addr == offsetof(struct compat_per_struct_kernel, cr11))
545 /* End address of the active per set. */
546 return test_thread_flag(TIF_SINGLE_STEP) ?
547 PSW32_ADDR_INSN : child->thread.per_user.end;
548 else if (addr == offsetof(struct compat_per_struct_kernel, bits))
549 /* Single-step bit. */
550 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
551 0x80000000 : 0;
552 else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
553 /* Start address of the user specified per set. */
554 return (__u32) child->thread.per_user.start;
555 else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
556 /* End address of the user specified per set. */
557 return (__u32) child->thread.per_user.end;
558 else if (addr == offsetof(struct compat_per_struct_kernel, perc_atmid))
559 /* PER code, ATMID and AI of the last PER trap */
560 return (__u32) child->thread.per_event.cause << 16;
561 else if (addr == offsetof(struct compat_per_struct_kernel, address))
562 /* Address of the last PER trap */
563 return (__u32) child->thread.per_event.address;
564 else if (addr == offsetof(struct compat_per_struct_kernel, access_id))
565 /* Access id of the last PER trap */
566 return (__u32) child->thread.per_event.paid << 24;
567 return 0;
568}
569
570/*
571 * Same as peek_user but for a 31 bit program.
572 */
573static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
574{
575 addr_t offset;
576 __u32 tmp;
577
578 if (addr < offsetof(struct compat_user, regs.acrs)) {
579 struct pt_regs *regs = task_pt_regs(child);
580 /*
581 * psw and gprs are stored on the stack
582 */
583 if (addr == offsetof(struct compat_user, regs.psw.mask)) {
584 /* Fake a 31 bit psw mask. */
585 tmp = (__u32)(regs->psw.mask >> 32);
586 tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
587 tmp |= PSW32_USER_BITS;
588 } else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
589 /* Fake a 31 bit psw address. */
590 tmp = (__u32) regs->psw.addr |
591 (__u32)(regs->psw.mask & PSW_MASK_BA);
592 } else {
593 /* gpr 0-15 */
594 tmp = *(__u32 *)((addr_t) ®s->psw + addr*2 + 4);
595 }
596 } else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
597 /*
598 * access registers are stored in the thread structure
599 */
600 offset = addr - offsetof(struct compat_user, regs.acrs);
601 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
602
603 } else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
604 /*
605 * orig_gpr2 is stored on the kernel stack
606 */
607 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
608
609 } else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
610 /*
611 * prevent reads of padding hole between
612 * orig_gpr2 and fp_regs on s390.
613 */
614 tmp = 0;
615
616 } else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
617 /*
618 * floating point control reg. is in the thread structure
619 */
620 tmp = child->thread.fpu.fpc;
621
622 } else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
623 /*
624 * floating point regs. are either in child->thread.fpu
625 * or the child->thread.fpu.vxrs array
626 */
627 offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
628 if (MACHINE_HAS_VX)
629 tmp = *(__u32 *)
630 ((addr_t) child->thread.fpu.vxrs + 2*offset);
631 else
632 tmp = *(__u32 *)
633 ((addr_t) child->thread.fpu.fprs + offset);
634
635 } else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
636 /*
637 * Handle access to the per_info structure.
638 */
639 addr -= offsetof(struct compat_user, regs.per_info);
640 tmp = __peek_user_per_compat(child, addr);
641
642 } else
643 tmp = 0;
644
645 return tmp;
646}
647
648static int peek_user_compat(struct task_struct *child,
649 addr_t addr, addr_t data)
650{
651 __u32 tmp;
652
653 if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
654 return -EIO;
655
656 tmp = __peek_user_compat(child, addr);
657 return put_user(tmp, (__u32 __user *) data);
658}
659
660/*
661 * Same as poke_user_per but for a 31 bit program.
662 */
663static inline void __poke_user_per_compat(struct task_struct *child,
664 addr_t addr, __u32 data)
665{
666 if (addr == offsetof(struct compat_per_struct_kernel, cr9))
667 /* PER event mask of the user specified per set. */
668 child->thread.per_user.control =
669 data & (PER_EVENT_MASK | PER_CONTROL_MASK);
670 else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
671 /* Starting address of the user specified per set. */
672 child->thread.per_user.start = data;
673 else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
674 /* Ending address of the user specified per set. */
675 child->thread.per_user.end = data;
676}
677
678/*
679 * Same as poke_user but for a 31 bit program.
680 */
681static int __poke_user_compat(struct task_struct *child,
682 addr_t addr, addr_t data)
683{
684 __u32 tmp = (__u32) data;
685 addr_t offset;
686
687 if (addr < offsetof(struct compat_user, regs.acrs)) {
688 struct pt_regs *regs = task_pt_regs(child);
689 /*
690 * psw, gprs, acrs and orig_gpr2 are stored on the stack
691 */
692 if (addr == offsetof(struct compat_user, regs.psw.mask)) {
693 __u32 mask = PSW32_MASK_USER;
694
695 mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
696 /* Build a 64 bit psw mask from 31 bit mask. */
697 if ((tmp ^ PSW32_USER_BITS) & ~mask)
698 /* Invalid psw mask. */
699 return -EINVAL;
700 if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
701 /* Invalid address-space-control bits */
702 return -EINVAL;
703 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
704 (regs->psw.mask & PSW_MASK_BA) |
705 (__u64)(tmp & mask) << 32;
706 } else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
707 /* Build a 64 bit psw address from 31 bit address. */
708 regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
709 /* Transfer 31 bit amode bit to psw mask. */
710 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
711 (__u64)(tmp & PSW32_ADDR_AMODE);
712 } else {
713 if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
714 addr == offsetof(struct compat_user, regs.gprs[2])) {
715 struct pt_regs *regs = task_pt_regs(child);
716
717 regs->int_code = 0x20000 | (data & 0xffff);
718 }
719 /* gpr 0-15 */
720 *(__u32*)((addr_t) ®s->psw + addr*2 + 4) = tmp;
721 }
722 } else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
723 /*
724 * access registers are stored in the thread structure
725 */
726 offset = addr - offsetof(struct compat_user, regs.acrs);
727 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
728
729 } else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
730 /*
731 * orig_gpr2 is stored on the kernel stack
732 */
733 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
734
735 } else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
736 /*
737 * prevent writess of padding hole between
738 * orig_gpr2 and fp_regs on s390.
739 */
740 return 0;
741
742 } else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
743 /*
744 * floating point control reg. is in the thread structure
745 */
746 if (test_fp_ctl(tmp))
747 return -EINVAL;
748 child->thread.fpu.fpc = data;
749
750 } else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
751 /*
752 * floating point regs. are either in child->thread.fpu
753 * or the child->thread.fpu.vxrs array
754 */
755 offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
756 if (MACHINE_HAS_VX)
757 *(__u32 *)((addr_t)
758 child->thread.fpu.vxrs + 2*offset) = tmp;
759 else
760 *(__u32 *)((addr_t)
761 child->thread.fpu.fprs + offset) = tmp;
762
763 } else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
764 /*
765 * Handle access to the per_info structure.
766 */
767 addr -= offsetof(struct compat_user, regs.per_info);
768 __poke_user_per_compat(child, addr, data);
769 }
770
771 return 0;
772}
773
774static int poke_user_compat(struct task_struct *child,
775 addr_t addr, addr_t data)
776{
777 if (!is_compat_task() || (addr & 3) ||
778 addr > sizeof(struct compat_user) - 3)
779 return -EIO;
780
781 return __poke_user_compat(child, addr, data);
782}
783
784long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
785 compat_ulong_t caddr, compat_ulong_t cdata)
786{
787 unsigned long addr = caddr;
788 unsigned long data = cdata;
789 compat_ptrace_area parea;
790 int copied, ret;
791
792 switch (request) {
793 case PTRACE_PEEKUSR:
794 /* read the word at location addr in the USER area. */
795 return peek_user_compat(child, addr, data);
796
797 case PTRACE_POKEUSR:
798 /* write the word at location addr in the USER area */
799 return poke_user_compat(child, addr, data);
800
801 case PTRACE_PEEKUSR_AREA:
802 case PTRACE_POKEUSR_AREA:
803 if (copy_from_user(&parea, (void __force __user *) addr,
804 sizeof(parea)))
805 return -EFAULT;
806 addr = parea.kernel_addr;
807 data = parea.process_addr;
808 copied = 0;
809 while (copied < parea.len) {
810 if (request == PTRACE_PEEKUSR_AREA)
811 ret = peek_user_compat(child, addr, data);
812 else {
813 __u32 utmp;
814 if (get_user(utmp,
815 (__u32 __force __user *) data))
816 return -EFAULT;
817 ret = poke_user_compat(child, addr, utmp);
818 }
819 if (ret)
820 return ret;
821 addr += sizeof(unsigned int);
822 data += sizeof(unsigned int);
823 copied += sizeof(unsigned int);
824 }
825 return 0;
826 case PTRACE_GET_LAST_BREAK:
827 put_user(child->thread.last_break,
828 (unsigned int __user *) data);
829 return 0;
830 }
831 return compat_ptrace_request(child, request, addr, data);
832}
833#endif
834
835/*
836 * user_regset definitions.
837 */
838
839static int s390_regs_get(struct task_struct *target,
840 const struct user_regset *regset,
841 struct membuf to)
842{
843 unsigned pos;
844 if (target == current)
845 save_access_regs(target->thread.acrs);
846
847 for (pos = 0; pos < sizeof(s390_regs); pos += sizeof(long))
848 membuf_store(&to, __peek_user(target, pos));
849 return 0;
850}
851
852static int s390_regs_set(struct task_struct *target,
853 const struct user_regset *regset,
854 unsigned int pos, unsigned int count,
855 const void *kbuf, const void __user *ubuf)
856{
857 int rc = 0;
858
859 if (target == current)
860 save_access_regs(target->thread.acrs);
861
862 if (kbuf) {
863 const unsigned long *k = kbuf;
864 while (count > 0 && !rc) {
865 rc = __poke_user(target, pos, *k++);
866 count -= sizeof(*k);
867 pos += sizeof(*k);
868 }
869 } else {
870 const unsigned long __user *u = ubuf;
871 while (count > 0 && !rc) {
872 unsigned long word;
873 rc = __get_user(word, u++);
874 if (rc)
875 break;
876 rc = __poke_user(target, pos, word);
877 count -= sizeof(*u);
878 pos += sizeof(*u);
879 }
880 }
881
882 if (rc == 0 && target == current)
883 restore_access_regs(target->thread.acrs);
884
885 return rc;
886}
887
888static int s390_fpregs_get(struct task_struct *target,
889 const struct user_regset *regset,
890 struct membuf to)
891{
892 _s390_fp_regs fp_regs;
893
894 if (target == current)
895 save_fpu_regs();
896
897 fp_regs.fpc = target->thread.fpu.fpc;
898 fpregs_store(&fp_regs, &target->thread.fpu);
899
900 return membuf_write(&to, &fp_regs, sizeof(fp_regs));
901}
902
903static int s390_fpregs_set(struct task_struct *target,
904 const struct user_regset *regset, unsigned int pos,
905 unsigned int count, const void *kbuf,
906 const void __user *ubuf)
907{
908 int rc = 0;
909 freg_t fprs[__NUM_FPRS];
910
911 if (target == current)
912 save_fpu_regs();
913
914 if (MACHINE_HAS_VX)
915 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
916 else
917 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
918
919 /* If setting FPC, must validate it first. */
920 if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
921 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
922 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
923 0, offsetof(s390_fp_regs, fprs));
924 if (rc)
925 return rc;
926 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
927 return -EINVAL;
928 target->thread.fpu.fpc = ufpc[0];
929 }
930
931 if (rc == 0 && count > 0)
932 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
933 fprs, offsetof(s390_fp_regs, fprs), -1);
934 if (rc)
935 return rc;
936
937 if (MACHINE_HAS_VX)
938 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
939 else
940 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
941
942 return rc;
943}
944
945static int s390_last_break_get(struct task_struct *target,
946 const struct user_regset *regset,
947 struct membuf to)
948{
949 return membuf_store(&to, target->thread.last_break);
950}
951
952static int s390_last_break_set(struct task_struct *target,
953 const struct user_regset *regset,
954 unsigned int pos, unsigned int count,
955 const void *kbuf, const void __user *ubuf)
956{
957 return 0;
958}
959
960static int s390_tdb_get(struct task_struct *target,
961 const struct user_regset *regset,
962 struct membuf to)
963{
964 struct pt_regs *regs = task_pt_regs(target);
965 size_t size;
966
967 if (!(regs->int_code & 0x200))
968 return -ENODATA;
969 size = sizeof(target->thread.trap_tdb.data);
970 return membuf_write(&to, target->thread.trap_tdb.data, size);
971}
972
973static int s390_tdb_set(struct task_struct *target,
974 const struct user_regset *regset,
975 unsigned int pos, unsigned int count,
976 const void *kbuf, const void __user *ubuf)
977{
978 return 0;
979}
980
981static int s390_vxrs_low_get(struct task_struct *target,
982 const struct user_regset *regset,
983 struct membuf to)
984{
985 __u64 vxrs[__NUM_VXRS_LOW];
986 int i;
987
988 if (!MACHINE_HAS_VX)
989 return -ENODEV;
990 if (target == current)
991 save_fpu_regs();
992 for (i = 0; i < __NUM_VXRS_LOW; i++)
993 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
994 return membuf_write(&to, vxrs, sizeof(vxrs));
995}
996
997static int s390_vxrs_low_set(struct task_struct *target,
998 const struct user_regset *regset,
999 unsigned int pos, unsigned int count,
1000 const void *kbuf, const void __user *ubuf)
1001{
1002 __u64 vxrs[__NUM_VXRS_LOW];
1003 int i, rc;
1004
1005 if (!MACHINE_HAS_VX)
1006 return -ENODEV;
1007 if (target == current)
1008 save_fpu_regs();
1009
1010 for (i = 0; i < __NUM_VXRS_LOW; i++)
1011 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1012
1013 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1014 if (rc == 0)
1015 for (i = 0; i < __NUM_VXRS_LOW; i++)
1016 *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1017
1018 return rc;
1019}
1020
1021static int s390_vxrs_high_get(struct task_struct *target,
1022 const struct user_regset *regset,
1023 struct membuf to)
1024{
1025 if (!MACHINE_HAS_VX)
1026 return -ENODEV;
1027 if (target == current)
1028 save_fpu_regs();
1029 return membuf_write(&to, target->thread.fpu.vxrs + __NUM_VXRS_LOW,
1030 __NUM_VXRS_HIGH * sizeof(__vector128));
1031}
1032
1033static int s390_vxrs_high_set(struct task_struct *target,
1034 const struct user_regset *regset,
1035 unsigned int pos, unsigned int count,
1036 const void *kbuf, const void __user *ubuf)
1037{
1038 int rc;
1039
1040 if (!MACHINE_HAS_VX)
1041 return -ENODEV;
1042 if (target == current)
1043 save_fpu_regs();
1044
1045 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1046 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1047 return rc;
1048}
1049
1050static int s390_system_call_get(struct task_struct *target,
1051 const struct user_regset *regset,
1052 struct membuf to)
1053{
1054 return membuf_store(&to, target->thread.system_call);
1055}
1056
1057static int s390_system_call_set(struct task_struct *target,
1058 const struct user_regset *regset,
1059 unsigned int pos, unsigned int count,
1060 const void *kbuf, const void __user *ubuf)
1061{
1062 unsigned int *data = &target->thread.system_call;
1063 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1064 data, 0, sizeof(unsigned int));
1065}
1066
1067static int s390_gs_cb_get(struct task_struct *target,
1068 const struct user_regset *regset,
1069 struct membuf to)
1070{
1071 struct gs_cb *data = target->thread.gs_cb;
1072
1073 if (!MACHINE_HAS_GS)
1074 return -ENODEV;
1075 if (!data)
1076 return -ENODATA;
1077 if (target == current)
1078 save_gs_cb(data);
1079 return membuf_write(&to, data, sizeof(struct gs_cb));
1080}
1081
1082static int s390_gs_cb_set(struct task_struct *target,
1083 const struct user_regset *regset,
1084 unsigned int pos, unsigned int count,
1085 const void *kbuf, const void __user *ubuf)
1086{
1087 struct gs_cb gs_cb = { }, *data = NULL;
1088 int rc;
1089
1090 if (!MACHINE_HAS_GS)
1091 return -ENODEV;
1092 if (!target->thread.gs_cb) {
1093 data = kzalloc(sizeof(*data), GFP_KERNEL);
1094 if (!data)
1095 return -ENOMEM;
1096 }
1097 if (!target->thread.gs_cb)
1098 gs_cb.gsd = 25;
1099 else if (target == current)
1100 save_gs_cb(&gs_cb);
1101 else
1102 gs_cb = *target->thread.gs_cb;
1103 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1104 &gs_cb, 0, sizeof(gs_cb));
1105 if (rc) {
1106 kfree(data);
1107 return -EFAULT;
1108 }
1109 preempt_disable();
1110 if (!target->thread.gs_cb)
1111 target->thread.gs_cb = data;
1112 *target->thread.gs_cb = gs_cb;
1113 if (target == current) {
1114 __ctl_set_bit(2, 4);
1115 restore_gs_cb(target->thread.gs_cb);
1116 }
1117 preempt_enable();
1118 return rc;
1119}
1120
1121static int s390_gs_bc_get(struct task_struct *target,
1122 const struct user_regset *regset,
1123 struct membuf to)
1124{
1125 struct gs_cb *data = target->thread.gs_bc_cb;
1126
1127 if (!MACHINE_HAS_GS)
1128 return -ENODEV;
1129 if (!data)
1130 return -ENODATA;
1131 return membuf_write(&to, data, sizeof(struct gs_cb));
1132}
1133
1134static int s390_gs_bc_set(struct task_struct *target,
1135 const struct user_regset *regset,
1136 unsigned int pos, unsigned int count,
1137 const void *kbuf, const void __user *ubuf)
1138{
1139 struct gs_cb *data = target->thread.gs_bc_cb;
1140
1141 if (!MACHINE_HAS_GS)
1142 return -ENODEV;
1143 if (!data) {
1144 data = kzalloc(sizeof(*data), GFP_KERNEL);
1145 if (!data)
1146 return -ENOMEM;
1147 target->thread.gs_bc_cb = data;
1148 }
1149 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1150 data, 0, sizeof(struct gs_cb));
1151}
1152
1153static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1154{
1155 return (cb->rca & 0x1f) == 0 &&
1156 (cb->roa & 0xfff) == 0 &&
1157 (cb->rla & 0xfff) == 0xfff &&
1158 cb->s == 1 &&
1159 cb->k == 1 &&
1160 cb->h == 0 &&
1161 cb->reserved1 == 0 &&
1162 cb->ps == 1 &&
1163 cb->qs == 0 &&
1164 cb->pc == 1 &&
1165 cb->qc == 0 &&
1166 cb->reserved2 == 0 &&
1167 cb->reserved3 == 0 &&
1168 cb->reserved4 == 0 &&
1169 cb->reserved5 == 0 &&
1170 cb->reserved6 == 0 &&
1171 cb->reserved7 == 0 &&
1172 cb->reserved8 == 0 &&
1173 cb->rla >= cb->roa &&
1174 cb->rca >= cb->roa &&
1175 cb->rca <= cb->rla+1 &&
1176 cb->m < 3;
1177}
1178
1179static int s390_runtime_instr_get(struct task_struct *target,
1180 const struct user_regset *regset,
1181 struct membuf to)
1182{
1183 struct runtime_instr_cb *data = target->thread.ri_cb;
1184
1185 if (!test_facility(64))
1186 return -ENODEV;
1187 if (!data)
1188 return -ENODATA;
1189
1190 return membuf_write(&to, data, sizeof(struct runtime_instr_cb));
1191}
1192
1193static int s390_runtime_instr_set(struct task_struct *target,
1194 const struct user_regset *regset,
1195 unsigned int pos, unsigned int count,
1196 const void *kbuf, const void __user *ubuf)
1197{
1198 struct runtime_instr_cb ri_cb = { }, *data = NULL;
1199 int rc;
1200
1201 if (!test_facility(64))
1202 return -ENODEV;
1203
1204 if (!target->thread.ri_cb) {
1205 data = kzalloc(sizeof(*data), GFP_KERNEL);
1206 if (!data)
1207 return -ENOMEM;
1208 }
1209
1210 if (target->thread.ri_cb) {
1211 if (target == current)
1212 store_runtime_instr_cb(&ri_cb);
1213 else
1214 ri_cb = *target->thread.ri_cb;
1215 }
1216
1217 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1218 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1219 if (rc) {
1220 kfree(data);
1221 return -EFAULT;
1222 }
1223
1224 if (!is_ri_cb_valid(&ri_cb)) {
1225 kfree(data);
1226 return -EINVAL;
1227 }
1228 /*
1229 * Override access key in any case, since user space should
1230 * not be able to set it, nor should it care about it.
1231 */
1232 ri_cb.key = PAGE_DEFAULT_KEY >> 4;
1233 preempt_disable();
1234 if (!target->thread.ri_cb)
1235 target->thread.ri_cb = data;
1236 *target->thread.ri_cb = ri_cb;
1237 if (target == current)
1238 load_runtime_instr_cb(target->thread.ri_cb);
1239 preempt_enable();
1240
1241 return 0;
1242}
1243
1244static const struct user_regset s390_regsets[] = {
1245 {
1246 .core_note_type = NT_PRSTATUS,
1247 .n = sizeof(s390_regs) / sizeof(long),
1248 .size = sizeof(long),
1249 .align = sizeof(long),
1250 .regset_get = s390_regs_get,
1251 .set = s390_regs_set,
1252 },
1253 {
1254 .core_note_type = NT_PRFPREG,
1255 .n = sizeof(s390_fp_regs) / sizeof(long),
1256 .size = sizeof(long),
1257 .align = sizeof(long),
1258 .regset_get = s390_fpregs_get,
1259 .set = s390_fpregs_set,
1260 },
1261 {
1262 .core_note_type = NT_S390_SYSTEM_CALL,
1263 .n = 1,
1264 .size = sizeof(unsigned int),
1265 .align = sizeof(unsigned int),
1266 .regset_get = s390_system_call_get,
1267 .set = s390_system_call_set,
1268 },
1269 {
1270 .core_note_type = NT_S390_LAST_BREAK,
1271 .n = 1,
1272 .size = sizeof(long),
1273 .align = sizeof(long),
1274 .regset_get = s390_last_break_get,
1275 .set = s390_last_break_set,
1276 },
1277 {
1278 .core_note_type = NT_S390_TDB,
1279 .n = 1,
1280 .size = 256,
1281 .align = 1,
1282 .regset_get = s390_tdb_get,
1283 .set = s390_tdb_set,
1284 },
1285 {
1286 .core_note_type = NT_S390_VXRS_LOW,
1287 .n = __NUM_VXRS_LOW,
1288 .size = sizeof(__u64),
1289 .align = sizeof(__u64),
1290 .regset_get = s390_vxrs_low_get,
1291 .set = s390_vxrs_low_set,
1292 },
1293 {
1294 .core_note_type = NT_S390_VXRS_HIGH,
1295 .n = __NUM_VXRS_HIGH,
1296 .size = sizeof(__vector128),
1297 .align = sizeof(__vector128),
1298 .regset_get = s390_vxrs_high_get,
1299 .set = s390_vxrs_high_set,
1300 },
1301 {
1302 .core_note_type = NT_S390_GS_CB,
1303 .n = sizeof(struct gs_cb) / sizeof(__u64),
1304 .size = sizeof(__u64),
1305 .align = sizeof(__u64),
1306 .regset_get = s390_gs_cb_get,
1307 .set = s390_gs_cb_set,
1308 },
1309 {
1310 .core_note_type = NT_S390_GS_BC,
1311 .n = sizeof(struct gs_cb) / sizeof(__u64),
1312 .size = sizeof(__u64),
1313 .align = sizeof(__u64),
1314 .regset_get = s390_gs_bc_get,
1315 .set = s390_gs_bc_set,
1316 },
1317 {
1318 .core_note_type = NT_S390_RI_CB,
1319 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1320 .size = sizeof(__u64),
1321 .align = sizeof(__u64),
1322 .regset_get = s390_runtime_instr_get,
1323 .set = s390_runtime_instr_set,
1324 },
1325};
1326
1327static const struct user_regset_view user_s390_view = {
1328 .name = "s390x",
1329 .e_machine = EM_S390,
1330 .regsets = s390_regsets,
1331 .n = ARRAY_SIZE(s390_regsets)
1332};
1333
1334#ifdef CONFIG_COMPAT
1335static int s390_compat_regs_get(struct task_struct *target,
1336 const struct user_regset *regset,
1337 struct membuf to)
1338{
1339 unsigned n;
1340
1341 if (target == current)
1342 save_access_regs(target->thread.acrs);
1343
1344 for (n = 0; n < sizeof(s390_compat_regs); n += sizeof(compat_ulong_t))
1345 membuf_store(&to, __peek_user_compat(target, n));
1346 return 0;
1347}
1348
1349static int s390_compat_regs_set(struct task_struct *target,
1350 const struct user_regset *regset,
1351 unsigned int pos, unsigned int count,
1352 const void *kbuf, const void __user *ubuf)
1353{
1354 int rc = 0;
1355
1356 if (target == current)
1357 save_access_regs(target->thread.acrs);
1358
1359 if (kbuf) {
1360 const compat_ulong_t *k = kbuf;
1361 while (count > 0 && !rc) {
1362 rc = __poke_user_compat(target, pos, *k++);
1363 count -= sizeof(*k);
1364 pos += sizeof(*k);
1365 }
1366 } else {
1367 const compat_ulong_t __user *u = ubuf;
1368 while (count > 0 && !rc) {
1369 compat_ulong_t word;
1370 rc = __get_user(word, u++);
1371 if (rc)
1372 break;
1373 rc = __poke_user_compat(target, pos, word);
1374 count -= sizeof(*u);
1375 pos += sizeof(*u);
1376 }
1377 }
1378
1379 if (rc == 0 && target == current)
1380 restore_access_regs(target->thread.acrs);
1381
1382 return rc;
1383}
1384
1385static int s390_compat_regs_high_get(struct task_struct *target,
1386 const struct user_regset *regset,
1387 struct membuf to)
1388{
1389 compat_ulong_t *gprs_high;
1390 int i;
1391
1392 gprs_high = (compat_ulong_t *)task_pt_regs(target)->gprs;
1393 for (i = 0; i < NUM_GPRS; i++, gprs_high += 2)
1394 membuf_store(&to, *gprs_high);
1395 return 0;
1396}
1397
1398static int s390_compat_regs_high_set(struct task_struct *target,
1399 const struct user_regset *regset,
1400 unsigned int pos, unsigned int count,
1401 const void *kbuf, const void __user *ubuf)
1402{
1403 compat_ulong_t *gprs_high;
1404 int rc = 0;
1405
1406 gprs_high = (compat_ulong_t *)
1407 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1408 if (kbuf) {
1409 const compat_ulong_t *k = kbuf;
1410 while (count > 0) {
1411 *gprs_high = *k++;
1412 *gprs_high += 2;
1413 count -= sizeof(*k);
1414 }
1415 } else {
1416 const compat_ulong_t __user *u = ubuf;
1417 while (count > 0 && !rc) {
1418 unsigned long word;
1419 rc = __get_user(word, u++);
1420 if (rc)
1421 break;
1422 *gprs_high = word;
1423 *gprs_high += 2;
1424 count -= sizeof(*u);
1425 }
1426 }
1427
1428 return rc;
1429}
1430
1431static int s390_compat_last_break_get(struct task_struct *target,
1432 const struct user_regset *regset,
1433 struct membuf to)
1434{
1435 compat_ulong_t last_break = target->thread.last_break;
1436
1437 return membuf_store(&to, (unsigned long)last_break);
1438}
1439
1440static int s390_compat_last_break_set(struct task_struct *target,
1441 const struct user_regset *regset,
1442 unsigned int pos, unsigned int count,
1443 const void *kbuf, const void __user *ubuf)
1444{
1445 return 0;
1446}
1447
1448static const struct user_regset s390_compat_regsets[] = {
1449 {
1450 .core_note_type = NT_PRSTATUS,
1451 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1452 .size = sizeof(compat_long_t),
1453 .align = sizeof(compat_long_t),
1454 .regset_get = s390_compat_regs_get,
1455 .set = s390_compat_regs_set,
1456 },
1457 {
1458 .core_note_type = NT_PRFPREG,
1459 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1460 .size = sizeof(compat_long_t),
1461 .align = sizeof(compat_long_t),
1462 .regset_get = s390_fpregs_get,
1463 .set = s390_fpregs_set,
1464 },
1465 {
1466 .core_note_type = NT_S390_SYSTEM_CALL,
1467 .n = 1,
1468 .size = sizeof(compat_uint_t),
1469 .align = sizeof(compat_uint_t),
1470 .regset_get = s390_system_call_get,
1471 .set = s390_system_call_set,
1472 },
1473 {
1474 .core_note_type = NT_S390_LAST_BREAK,
1475 .n = 1,
1476 .size = sizeof(long),
1477 .align = sizeof(long),
1478 .regset_get = s390_compat_last_break_get,
1479 .set = s390_compat_last_break_set,
1480 },
1481 {
1482 .core_note_type = NT_S390_TDB,
1483 .n = 1,
1484 .size = 256,
1485 .align = 1,
1486 .regset_get = s390_tdb_get,
1487 .set = s390_tdb_set,
1488 },
1489 {
1490 .core_note_type = NT_S390_VXRS_LOW,
1491 .n = __NUM_VXRS_LOW,
1492 .size = sizeof(__u64),
1493 .align = sizeof(__u64),
1494 .regset_get = s390_vxrs_low_get,
1495 .set = s390_vxrs_low_set,
1496 },
1497 {
1498 .core_note_type = NT_S390_VXRS_HIGH,
1499 .n = __NUM_VXRS_HIGH,
1500 .size = sizeof(__vector128),
1501 .align = sizeof(__vector128),
1502 .regset_get = s390_vxrs_high_get,
1503 .set = s390_vxrs_high_set,
1504 },
1505 {
1506 .core_note_type = NT_S390_HIGH_GPRS,
1507 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1508 .size = sizeof(compat_long_t),
1509 .align = sizeof(compat_long_t),
1510 .regset_get = s390_compat_regs_high_get,
1511 .set = s390_compat_regs_high_set,
1512 },
1513 {
1514 .core_note_type = NT_S390_GS_CB,
1515 .n = sizeof(struct gs_cb) / sizeof(__u64),
1516 .size = sizeof(__u64),
1517 .align = sizeof(__u64),
1518 .regset_get = s390_gs_cb_get,
1519 .set = s390_gs_cb_set,
1520 },
1521 {
1522 .core_note_type = NT_S390_GS_BC,
1523 .n = sizeof(struct gs_cb) / sizeof(__u64),
1524 .size = sizeof(__u64),
1525 .align = sizeof(__u64),
1526 .regset_get = s390_gs_bc_get,
1527 .set = s390_gs_bc_set,
1528 },
1529 {
1530 .core_note_type = NT_S390_RI_CB,
1531 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1532 .size = sizeof(__u64),
1533 .align = sizeof(__u64),
1534 .regset_get = s390_runtime_instr_get,
1535 .set = s390_runtime_instr_set,
1536 },
1537};
1538
1539static const struct user_regset_view user_s390_compat_view = {
1540 .name = "s390",
1541 .e_machine = EM_S390,
1542 .regsets = s390_compat_regsets,
1543 .n = ARRAY_SIZE(s390_compat_regsets)
1544};
1545#endif
1546
1547const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1548{
1549#ifdef CONFIG_COMPAT
1550 if (test_tsk_thread_flag(task, TIF_31BIT))
1551 return &user_s390_compat_view;
1552#endif
1553 return &user_s390_view;
1554}
1555
1556static const char *gpr_names[NUM_GPRS] = {
1557 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
1558 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1559};
1560
1561unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1562{
1563 if (offset >= NUM_GPRS)
1564 return 0;
1565 return regs->gprs[offset];
1566}
1567
1568int regs_query_register_offset(const char *name)
1569{
1570 unsigned long offset;
1571
1572 if (!name || *name != 'r')
1573 return -EINVAL;
1574 if (kstrtoul(name + 1, 10, &offset))
1575 return -EINVAL;
1576 if (offset >= NUM_GPRS)
1577 return -EINVAL;
1578 return offset;
1579}
1580
1581const char *regs_query_register_name(unsigned int offset)
1582{
1583 if (offset >= NUM_GPRS)
1584 return NULL;
1585 return gpr_names[offset];
1586}
1587
1588static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1589{
1590 unsigned long ksp = kernel_stack_pointer(regs);
1591
1592 return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1593}
1594
1595/**
1596 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1597 * @regs:pt_regs which contains kernel stack pointer.
1598 * @n:stack entry number.
1599 *
1600 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1601 * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1602 * this returns 0.
1603 */
1604unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1605{
1606 unsigned long addr;
1607
1608 addr = kernel_stack_pointer(regs) + n * sizeof(long);
1609 if (!regs_within_kernel_stack(regs, addr))
1610 return 0;
1611 return *(unsigned long *)addr;
1612}
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 <linux/kernel.h>
11#include <linux/sched.h>
12#include <linux/sched/task_stack.h>
13#include <linux/mm.h>
14#include <linux/smp.h>
15#include <linux/errno.h>
16#include <linux/ptrace.h>
17#include <linux/user.h>
18#include <linux/security.h>
19#include <linux/audit.h>
20#include <linux/signal.h>
21#include <linux/elf.h>
22#include <linux/regset.h>
23#include <linux/tracehook.h>
24#include <linux/seccomp.h>
25#include <linux/compat.h>
26#include <trace/syscall.h>
27#include <asm/page.h>
28#include <asm/pgtable.h>
29#include <asm/pgalloc.h>
30#include <linux/uaccess.h>
31#include <asm/unistd.h>
32#include <asm/switch_to.h>
33#include <asm/runtime_instr.h>
34#include <asm/facility.h>
35
36#include "entry.h"
37
38#ifdef CONFIG_COMPAT
39#include "compat_ptrace.h"
40#endif
41
42#define CREATE_TRACE_POINTS
43#include <trace/events/syscalls.h>
44
45void update_cr_regs(struct task_struct *task)
46{
47 struct pt_regs *regs = task_pt_regs(task);
48 struct thread_struct *thread = &task->thread;
49 struct per_regs old, new;
50 union ctlreg0 cr0_old, cr0_new;
51 union ctlreg2 cr2_old, cr2_new;
52 int cr0_changed, cr2_changed;
53
54 __ctl_store(cr0_old.val, 0, 0);
55 __ctl_store(cr2_old.val, 2, 2);
56 cr0_new = cr0_old;
57 cr2_new = cr2_old;
58 /* Take care of the enable/disable of transactional execution. */
59 if (MACHINE_HAS_TE) {
60 /* Set or clear transaction execution TXC bit 8. */
61 cr0_new.tcx = 1;
62 if (task->thread.per_flags & PER_FLAG_NO_TE)
63 cr0_new.tcx = 0;
64 /* Set or clear transaction execution TDC bits 62 and 63. */
65 cr2_new.tdc = 0;
66 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
67 if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
68 cr2_new.tdc = 1;
69 else
70 cr2_new.tdc = 2;
71 }
72 }
73 /* Take care of enable/disable of guarded storage. */
74 if (MACHINE_HAS_GS) {
75 cr2_new.gse = 0;
76 if (task->thread.gs_cb)
77 cr2_new.gse = 1;
78 }
79 /* Load control register 0/2 iff changed */
80 cr0_changed = cr0_new.val != cr0_old.val;
81 cr2_changed = cr2_new.val != cr2_old.val;
82 if (cr0_changed)
83 __ctl_load(cr0_new.val, 0, 0);
84 if (cr2_changed)
85 __ctl_load(cr2_new.val, 2, 2);
86 /* Copy user specified PER registers */
87 new.control = thread->per_user.control;
88 new.start = thread->per_user.start;
89 new.end = thread->per_user.end;
90
91 /* merge TIF_SINGLE_STEP into user specified PER registers. */
92 if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
93 test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
94 if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
95 new.control |= PER_EVENT_BRANCH;
96 else
97 new.control |= PER_EVENT_IFETCH;
98 new.control |= PER_CONTROL_SUSPENSION;
99 new.control |= PER_EVENT_TRANSACTION_END;
100 if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
101 new.control |= PER_EVENT_IFETCH;
102 new.start = 0;
103 new.end = -1UL;
104 }
105
106 /* Take care of the PER enablement bit in the PSW. */
107 if (!(new.control & PER_EVENT_MASK)) {
108 regs->psw.mask &= ~PSW_MASK_PER;
109 return;
110 }
111 regs->psw.mask |= PSW_MASK_PER;
112 __ctl_store(old, 9, 11);
113 if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
114 __ctl_load(new, 9, 11);
115}
116
117void user_enable_single_step(struct task_struct *task)
118{
119 clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
120 set_tsk_thread_flag(task, TIF_SINGLE_STEP);
121}
122
123void user_disable_single_step(struct task_struct *task)
124{
125 clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
126 clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
127}
128
129void user_enable_block_step(struct task_struct *task)
130{
131 set_tsk_thread_flag(task, TIF_SINGLE_STEP);
132 set_tsk_thread_flag(task, TIF_BLOCK_STEP);
133}
134
135/*
136 * Called by kernel/ptrace.c when detaching..
137 *
138 * Clear all debugging related fields.
139 */
140void ptrace_disable(struct task_struct *task)
141{
142 memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
143 memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
144 clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
145 clear_pt_regs_flag(task_pt_regs(task), PIF_PER_TRAP);
146 task->thread.per_flags = 0;
147}
148
149#define __ADDR_MASK 7
150
151static inline unsigned long __peek_user_per(struct task_struct *child,
152 addr_t addr)
153{
154 struct per_struct_kernel *dummy = NULL;
155
156 if (addr == (addr_t) &dummy->cr9)
157 /* Control bits of the active per set. */
158 return test_thread_flag(TIF_SINGLE_STEP) ?
159 PER_EVENT_IFETCH : child->thread.per_user.control;
160 else if (addr == (addr_t) &dummy->cr10)
161 /* Start address of the active per set. */
162 return test_thread_flag(TIF_SINGLE_STEP) ?
163 0 : child->thread.per_user.start;
164 else if (addr == (addr_t) &dummy->cr11)
165 /* End address of the active per set. */
166 return test_thread_flag(TIF_SINGLE_STEP) ?
167 -1UL : child->thread.per_user.end;
168 else if (addr == (addr_t) &dummy->bits)
169 /* Single-step bit. */
170 return test_thread_flag(TIF_SINGLE_STEP) ?
171 (1UL << (BITS_PER_LONG - 1)) : 0;
172 else if (addr == (addr_t) &dummy->starting_addr)
173 /* Start address of the user specified per set. */
174 return child->thread.per_user.start;
175 else if (addr == (addr_t) &dummy->ending_addr)
176 /* End address of the user specified per set. */
177 return child->thread.per_user.end;
178 else if (addr == (addr_t) &dummy->perc_atmid)
179 /* PER code, ATMID and AI of the last PER trap */
180 return (unsigned long)
181 child->thread.per_event.cause << (BITS_PER_LONG - 16);
182 else if (addr == (addr_t) &dummy->address)
183 /* Address of the last PER trap */
184 return child->thread.per_event.address;
185 else if (addr == (addr_t) &dummy->access_id)
186 /* Access id of the last PER trap */
187 return (unsigned long)
188 child->thread.per_event.paid << (BITS_PER_LONG - 8);
189 return 0;
190}
191
192/*
193 * Read the word at offset addr from the user area of a process. The
194 * trouble here is that the information is littered over different
195 * locations. The process registers are found on the kernel stack,
196 * the floating point stuff and the trace settings are stored in
197 * the task structure. In addition the different structures in
198 * struct user contain pad bytes that should be read as zeroes.
199 * Lovely...
200 */
201static unsigned long __peek_user(struct task_struct *child, addr_t addr)
202{
203 struct user *dummy = NULL;
204 addr_t offset, tmp;
205
206 if (addr < (addr_t) &dummy->regs.acrs) {
207 /*
208 * psw and gprs are stored on the stack
209 */
210 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
211 if (addr == (addr_t) &dummy->regs.psw.mask) {
212 /* Return a clean psw mask. */
213 tmp &= PSW_MASK_USER | PSW_MASK_RI;
214 tmp |= PSW_USER_BITS;
215 }
216
217 } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
218 /*
219 * access registers are stored in the thread structure
220 */
221 offset = addr - (addr_t) &dummy->regs.acrs;
222 /*
223 * Very special case: old & broken 64 bit gdb reading
224 * from acrs[15]. Result is a 64 bit value. Read the
225 * 32 bit acrs[15] value and shift it by 32. Sick...
226 */
227 if (addr == (addr_t) &dummy->regs.acrs[15])
228 tmp = ((unsigned long) child->thread.acrs[15]) << 32;
229 else
230 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
231
232 } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
233 /*
234 * orig_gpr2 is stored on the kernel stack
235 */
236 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
237
238 } else if (addr < (addr_t) &dummy->regs.fp_regs) {
239 /*
240 * prevent reads of padding hole between
241 * orig_gpr2 and fp_regs on s390.
242 */
243 tmp = 0;
244
245 } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
246 /*
247 * floating point control reg. is in the thread structure
248 */
249 tmp = child->thread.fpu.fpc;
250 tmp <<= BITS_PER_LONG - 32;
251
252 } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
253 /*
254 * floating point regs. are either in child->thread.fpu
255 * or the child->thread.fpu.vxrs array
256 */
257 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
258 if (MACHINE_HAS_VX)
259 tmp = *(addr_t *)
260 ((addr_t) child->thread.fpu.vxrs + 2*offset);
261 else
262 tmp = *(addr_t *)
263 ((addr_t) child->thread.fpu.fprs + offset);
264
265 } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
266 /*
267 * Handle access to the per_info structure.
268 */
269 addr -= (addr_t) &dummy->regs.per_info;
270 tmp = __peek_user_per(child, addr);
271
272 } else
273 tmp = 0;
274
275 return tmp;
276}
277
278static int
279peek_user(struct task_struct *child, addr_t addr, addr_t data)
280{
281 addr_t tmp, mask;
282
283 /*
284 * Stupid gdb peeks/pokes the access registers in 64 bit with
285 * an alignment of 4. Programmers from hell...
286 */
287 mask = __ADDR_MASK;
288 if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
289 addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
290 mask = 3;
291 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
292 return -EIO;
293
294 tmp = __peek_user(child, addr);
295 return put_user(tmp, (addr_t __user *) data);
296}
297
298static inline void __poke_user_per(struct task_struct *child,
299 addr_t addr, addr_t data)
300{
301 struct per_struct_kernel *dummy = NULL;
302
303 /*
304 * There are only three fields in the per_info struct that the
305 * debugger user can write to.
306 * 1) cr9: the debugger wants to set a new PER event mask
307 * 2) starting_addr: the debugger wants to set a new starting
308 * address to use with the PER event mask.
309 * 3) ending_addr: the debugger wants to set a new ending
310 * address to use with the PER event mask.
311 * The user specified PER event mask and the start and end
312 * addresses are used only if single stepping is not in effect.
313 * Writes to any other field in per_info are ignored.
314 */
315 if (addr == (addr_t) &dummy->cr9)
316 /* PER event mask of the user specified per set. */
317 child->thread.per_user.control =
318 data & (PER_EVENT_MASK | PER_CONTROL_MASK);
319 else if (addr == (addr_t) &dummy->starting_addr)
320 /* Starting address of the user specified per set. */
321 child->thread.per_user.start = data;
322 else if (addr == (addr_t) &dummy->ending_addr)
323 /* Ending address of the user specified per set. */
324 child->thread.per_user.end = data;
325}
326
327/*
328 * Write a word to the user area of a process at location addr. This
329 * operation does have an additional problem compared to peek_user.
330 * Stores to the program status word and on the floating point
331 * control register needs to get checked for validity.
332 */
333static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
334{
335 struct user *dummy = NULL;
336 addr_t offset;
337
338 if (addr < (addr_t) &dummy->regs.acrs) {
339 /*
340 * psw and gprs are stored on the stack
341 */
342 if (addr == (addr_t) &dummy->regs.psw.mask) {
343 unsigned long mask = PSW_MASK_USER;
344
345 mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
346 if ((data ^ PSW_USER_BITS) & ~mask)
347 /* Invalid psw mask. */
348 return -EINVAL;
349 if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
350 /* Invalid address-space-control bits */
351 return -EINVAL;
352 if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
353 /* Invalid addressing mode bits */
354 return -EINVAL;
355 }
356 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
357
358 } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
359 /*
360 * access registers are stored in the thread structure
361 */
362 offset = addr - (addr_t) &dummy->regs.acrs;
363 /*
364 * Very special case: old & broken 64 bit gdb writing
365 * to acrs[15] with a 64 bit value. Ignore the lower
366 * half of the value and write the upper 32 bit to
367 * acrs[15]. Sick...
368 */
369 if (addr == (addr_t) &dummy->regs.acrs[15])
370 child->thread.acrs[15] = (unsigned int) (data >> 32);
371 else
372 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
373
374 } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
375 /*
376 * orig_gpr2 is stored on the kernel stack
377 */
378 task_pt_regs(child)->orig_gpr2 = data;
379
380 } else if (addr < (addr_t) &dummy->regs.fp_regs) {
381 /*
382 * prevent writes of padding hole between
383 * orig_gpr2 and fp_regs on s390.
384 */
385 return 0;
386
387 } else if (addr == (addr_t) &dummy->regs.fp_regs.fpc) {
388 /*
389 * floating point control reg. is in the thread structure
390 */
391 if ((unsigned int) data != 0 ||
392 test_fp_ctl(data >> (BITS_PER_LONG - 32)))
393 return -EINVAL;
394 child->thread.fpu.fpc = data >> (BITS_PER_LONG - 32);
395
396 } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
397 /*
398 * floating point regs. are either in child->thread.fpu
399 * or the child->thread.fpu.vxrs array
400 */
401 offset = addr - (addr_t) &dummy->regs.fp_regs.fprs;
402 if (MACHINE_HAS_VX)
403 *(addr_t *)((addr_t)
404 child->thread.fpu.vxrs + 2*offset) = data;
405 else
406 *(addr_t *)((addr_t)
407 child->thread.fpu.fprs + offset) = data;
408
409 } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
410 /*
411 * Handle access to the per_info structure.
412 */
413 addr -= (addr_t) &dummy->regs.per_info;
414 __poke_user_per(child, addr, data);
415
416 }
417
418 return 0;
419}
420
421static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
422{
423 addr_t mask;
424
425 /*
426 * Stupid gdb peeks/pokes the access registers in 64 bit with
427 * an alignment of 4. Programmers from hell indeed...
428 */
429 mask = __ADDR_MASK;
430 if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
431 addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
432 mask = 3;
433 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
434 return -EIO;
435
436 return __poke_user(child, addr, data);
437}
438
439long arch_ptrace(struct task_struct *child, long request,
440 unsigned long addr, unsigned long data)
441{
442 ptrace_area parea;
443 int copied, ret;
444
445 switch (request) {
446 case PTRACE_PEEKUSR:
447 /* read the word at location addr in the USER area. */
448 return peek_user(child, addr, data);
449
450 case PTRACE_POKEUSR:
451 /* write the word at location addr in the USER area */
452 return poke_user(child, addr, data);
453
454 case PTRACE_PEEKUSR_AREA:
455 case PTRACE_POKEUSR_AREA:
456 if (copy_from_user(&parea, (void __force __user *) addr,
457 sizeof(parea)))
458 return -EFAULT;
459 addr = parea.kernel_addr;
460 data = parea.process_addr;
461 copied = 0;
462 while (copied < parea.len) {
463 if (request == PTRACE_PEEKUSR_AREA)
464 ret = peek_user(child, addr, data);
465 else {
466 addr_t utmp;
467 if (get_user(utmp,
468 (addr_t __force __user *) data))
469 return -EFAULT;
470 ret = poke_user(child, addr, utmp);
471 }
472 if (ret)
473 return ret;
474 addr += sizeof(unsigned long);
475 data += sizeof(unsigned long);
476 copied += sizeof(unsigned long);
477 }
478 return 0;
479 case PTRACE_GET_LAST_BREAK:
480 put_user(child->thread.last_break,
481 (unsigned long __user *) data);
482 return 0;
483 case PTRACE_ENABLE_TE:
484 if (!MACHINE_HAS_TE)
485 return -EIO;
486 child->thread.per_flags &= ~PER_FLAG_NO_TE;
487 return 0;
488 case PTRACE_DISABLE_TE:
489 if (!MACHINE_HAS_TE)
490 return -EIO;
491 child->thread.per_flags |= PER_FLAG_NO_TE;
492 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
493 return 0;
494 case PTRACE_TE_ABORT_RAND:
495 if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
496 return -EIO;
497 switch (data) {
498 case 0UL:
499 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
500 break;
501 case 1UL:
502 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
503 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
504 break;
505 case 2UL:
506 child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
507 child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
508 break;
509 default:
510 return -EINVAL;
511 }
512 return 0;
513 default:
514 return ptrace_request(child, request, addr, data);
515 }
516}
517
518#ifdef CONFIG_COMPAT
519/*
520 * Now the fun part starts... a 31 bit program running in the
521 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
522 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
523 * to handle, the difference to the 64 bit versions of the requests
524 * is that the access is done in multiples of 4 byte instead of
525 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
526 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
527 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
528 * is a 31 bit program too, the content of struct user can be
529 * emulated. A 31 bit program peeking into the struct user of
530 * a 64 bit program is a no-no.
531 */
532
533/*
534 * Same as peek_user_per but for a 31 bit program.
535 */
536static inline __u32 __peek_user_per_compat(struct task_struct *child,
537 addr_t addr)
538{
539 struct compat_per_struct_kernel *dummy32 = NULL;
540
541 if (addr == (addr_t) &dummy32->cr9)
542 /* Control bits of the active per set. */
543 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
544 PER_EVENT_IFETCH : child->thread.per_user.control;
545 else if (addr == (addr_t) &dummy32->cr10)
546 /* Start address of the active per set. */
547 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
548 0 : child->thread.per_user.start;
549 else if (addr == (addr_t) &dummy32->cr11)
550 /* End address of the active per set. */
551 return test_thread_flag(TIF_SINGLE_STEP) ?
552 PSW32_ADDR_INSN : child->thread.per_user.end;
553 else if (addr == (addr_t) &dummy32->bits)
554 /* Single-step bit. */
555 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
556 0x80000000 : 0;
557 else if (addr == (addr_t) &dummy32->starting_addr)
558 /* Start address of the user specified per set. */
559 return (__u32) child->thread.per_user.start;
560 else if (addr == (addr_t) &dummy32->ending_addr)
561 /* End address of the user specified per set. */
562 return (__u32) child->thread.per_user.end;
563 else if (addr == (addr_t) &dummy32->perc_atmid)
564 /* PER code, ATMID and AI of the last PER trap */
565 return (__u32) child->thread.per_event.cause << 16;
566 else if (addr == (addr_t) &dummy32->address)
567 /* Address of the last PER trap */
568 return (__u32) child->thread.per_event.address;
569 else if (addr == (addr_t) &dummy32->access_id)
570 /* Access id of the last PER trap */
571 return (__u32) child->thread.per_event.paid << 24;
572 return 0;
573}
574
575/*
576 * Same as peek_user but for a 31 bit program.
577 */
578static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
579{
580 struct compat_user *dummy32 = NULL;
581 addr_t offset;
582 __u32 tmp;
583
584 if (addr < (addr_t) &dummy32->regs.acrs) {
585 struct pt_regs *regs = task_pt_regs(child);
586 /*
587 * psw and gprs are stored on the stack
588 */
589 if (addr == (addr_t) &dummy32->regs.psw.mask) {
590 /* Fake a 31 bit psw mask. */
591 tmp = (__u32)(regs->psw.mask >> 32);
592 tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
593 tmp |= PSW32_USER_BITS;
594 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
595 /* Fake a 31 bit psw address. */
596 tmp = (__u32) regs->psw.addr |
597 (__u32)(regs->psw.mask & PSW_MASK_BA);
598 } else {
599 /* gpr 0-15 */
600 tmp = *(__u32 *)((addr_t) ®s->psw + addr*2 + 4);
601 }
602 } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
603 /*
604 * access registers are stored in the thread structure
605 */
606 offset = addr - (addr_t) &dummy32->regs.acrs;
607 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
608
609 } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
610 /*
611 * orig_gpr2 is stored on the kernel stack
612 */
613 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
614
615 } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
616 /*
617 * prevent reads of padding hole between
618 * orig_gpr2 and fp_regs on s390.
619 */
620 tmp = 0;
621
622 } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
623 /*
624 * floating point control reg. is in the thread structure
625 */
626 tmp = child->thread.fpu.fpc;
627
628 } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
629 /*
630 * floating point regs. are either in child->thread.fpu
631 * or the child->thread.fpu.vxrs array
632 */
633 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
634 if (MACHINE_HAS_VX)
635 tmp = *(__u32 *)
636 ((addr_t) child->thread.fpu.vxrs + 2*offset);
637 else
638 tmp = *(__u32 *)
639 ((addr_t) child->thread.fpu.fprs + offset);
640
641 } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
642 /*
643 * Handle access to the per_info structure.
644 */
645 addr -= (addr_t) &dummy32->regs.per_info;
646 tmp = __peek_user_per_compat(child, addr);
647
648 } else
649 tmp = 0;
650
651 return tmp;
652}
653
654static int peek_user_compat(struct task_struct *child,
655 addr_t addr, addr_t data)
656{
657 __u32 tmp;
658
659 if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
660 return -EIO;
661
662 tmp = __peek_user_compat(child, addr);
663 return put_user(tmp, (__u32 __user *) data);
664}
665
666/*
667 * Same as poke_user_per but for a 31 bit program.
668 */
669static inline void __poke_user_per_compat(struct task_struct *child,
670 addr_t addr, __u32 data)
671{
672 struct compat_per_struct_kernel *dummy32 = NULL;
673
674 if (addr == (addr_t) &dummy32->cr9)
675 /* PER event mask of the user specified per set. */
676 child->thread.per_user.control =
677 data & (PER_EVENT_MASK | PER_CONTROL_MASK);
678 else if (addr == (addr_t) &dummy32->starting_addr)
679 /* Starting address of the user specified per set. */
680 child->thread.per_user.start = data;
681 else if (addr == (addr_t) &dummy32->ending_addr)
682 /* Ending address of the user specified per set. */
683 child->thread.per_user.end = data;
684}
685
686/*
687 * Same as poke_user but for a 31 bit program.
688 */
689static int __poke_user_compat(struct task_struct *child,
690 addr_t addr, addr_t data)
691{
692 struct compat_user *dummy32 = NULL;
693 __u32 tmp = (__u32) data;
694 addr_t offset;
695
696 if (addr < (addr_t) &dummy32->regs.acrs) {
697 struct pt_regs *regs = task_pt_regs(child);
698 /*
699 * psw, gprs, acrs and orig_gpr2 are stored on the stack
700 */
701 if (addr == (addr_t) &dummy32->regs.psw.mask) {
702 __u32 mask = PSW32_MASK_USER;
703
704 mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
705 /* Build a 64 bit psw mask from 31 bit mask. */
706 if ((tmp ^ PSW32_USER_BITS) & ~mask)
707 /* Invalid psw mask. */
708 return -EINVAL;
709 if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
710 /* Invalid address-space-control bits */
711 return -EINVAL;
712 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
713 (regs->psw.mask & PSW_MASK_BA) |
714 (__u64)(tmp & mask) << 32;
715 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
716 /* Build a 64 bit psw address from 31 bit address. */
717 regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
718 /* Transfer 31 bit amode bit to psw mask. */
719 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
720 (__u64)(tmp & PSW32_ADDR_AMODE);
721 } else {
722 /* gpr 0-15 */
723 *(__u32*)((addr_t) ®s->psw + addr*2 + 4) = tmp;
724 }
725 } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
726 /*
727 * access registers are stored in the thread structure
728 */
729 offset = addr - (addr_t) &dummy32->regs.acrs;
730 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
731
732 } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
733 /*
734 * orig_gpr2 is stored on the kernel stack
735 */
736 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
737
738 } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
739 /*
740 * prevent writess of padding hole between
741 * orig_gpr2 and fp_regs on s390.
742 */
743 return 0;
744
745 } else if (addr == (addr_t) &dummy32->regs.fp_regs.fpc) {
746 /*
747 * floating point control reg. is in the thread structure
748 */
749 if (test_fp_ctl(tmp))
750 return -EINVAL;
751 child->thread.fpu.fpc = data;
752
753 } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
754 /*
755 * floating point regs. are either in child->thread.fpu
756 * or the child->thread.fpu.vxrs array
757 */
758 offset = addr - (addr_t) &dummy32->regs.fp_regs.fprs;
759 if (MACHINE_HAS_VX)
760 *(__u32 *)((addr_t)
761 child->thread.fpu.vxrs + 2*offset) = tmp;
762 else
763 *(__u32 *)((addr_t)
764 child->thread.fpu.fprs + offset) = tmp;
765
766 } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
767 /*
768 * Handle access to the per_info structure.
769 */
770 addr -= (addr_t) &dummy32->regs.per_info;
771 __poke_user_per_compat(child, addr, data);
772 }
773
774 return 0;
775}
776
777static int poke_user_compat(struct task_struct *child,
778 addr_t addr, addr_t data)
779{
780 if (!is_compat_task() || (addr & 3) ||
781 addr > sizeof(struct compat_user) - 3)
782 return -EIO;
783
784 return __poke_user_compat(child, addr, data);
785}
786
787long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
788 compat_ulong_t caddr, compat_ulong_t cdata)
789{
790 unsigned long addr = caddr;
791 unsigned long data = cdata;
792 compat_ptrace_area parea;
793 int copied, ret;
794
795 switch (request) {
796 case PTRACE_PEEKUSR:
797 /* read the word at location addr in the USER area. */
798 return peek_user_compat(child, addr, data);
799
800 case PTRACE_POKEUSR:
801 /* write the word at location addr in the USER area */
802 return poke_user_compat(child, addr, data);
803
804 case PTRACE_PEEKUSR_AREA:
805 case PTRACE_POKEUSR_AREA:
806 if (copy_from_user(&parea, (void __force __user *) addr,
807 sizeof(parea)))
808 return -EFAULT;
809 addr = parea.kernel_addr;
810 data = parea.process_addr;
811 copied = 0;
812 while (copied < parea.len) {
813 if (request == PTRACE_PEEKUSR_AREA)
814 ret = peek_user_compat(child, addr, data);
815 else {
816 __u32 utmp;
817 if (get_user(utmp,
818 (__u32 __force __user *) data))
819 return -EFAULT;
820 ret = poke_user_compat(child, addr, utmp);
821 }
822 if (ret)
823 return ret;
824 addr += sizeof(unsigned int);
825 data += sizeof(unsigned int);
826 copied += sizeof(unsigned int);
827 }
828 return 0;
829 case PTRACE_GET_LAST_BREAK:
830 put_user(child->thread.last_break,
831 (unsigned int __user *) data);
832 return 0;
833 }
834 return compat_ptrace_request(child, request, addr, data);
835}
836#endif
837
838asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
839{
840 unsigned long mask = -1UL;
841
842 /*
843 * The sysc_tracesys code in entry.S stored the system
844 * call number to gprs[2].
845 */
846 if (test_thread_flag(TIF_SYSCALL_TRACE) &&
847 (tracehook_report_syscall_entry(regs) ||
848 regs->gprs[2] >= NR_syscalls)) {
849 /*
850 * Tracing decided this syscall should not happen or the
851 * debugger stored an invalid system call number. Skip
852 * the system call and the system call restart handling.
853 */
854 clear_pt_regs_flag(regs, PIF_SYSCALL);
855 return -1;
856 }
857
858 /* Do the secure computing check after ptrace. */
859 if (secure_computing(NULL)) {
860 /* seccomp failures shouldn't expose any additional code. */
861 return -1;
862 }
863
864 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
865 trace_sys_enter(regs, regs->gprs[2]);
866
867 if (is_compat_task())
868 mask = 0xffffffff;
869
870 audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask,
871 regs->gprs[3] &mask, regs->gprs[4] &mask,
872 regs->gprs[5] &mask);
873
874 return regs->gprs[2];
875}
876
877asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
878{
879 audit_syscall_exit(regs);
880
881 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
882 trace_sys_exit(regs, regs->gprs[2]);
883
884 if (test_thread_flag(TIF_SYSCALL_TRACE))
885 tracehook_report_syscall_exit(regs, 0);
886}
887
888/*
889 * user_regset definitions.
890 */
891
892static int s390_regs_get(struct task_struct *target,
893 const struct user_regset *regset,
894 unsigned int pos, unsigned int count,
895 void *kbuf, void __user *ubuf)
896{
897 if (target == current)
898 save_access_regs(target->thread.acrs);
899
900 if (kbuf) {
901 unsigned long *k = kbuf;
902 while (count > 0) {
903 *k++ = __peek_user(target, pos);
904 count -= sizeof(*k);
905 pos += sizeof(*k);
906 }
907 } else {
908 unsigned long __user *u = ubuf;
909 while (count > 0) {
910 if (__put_user(__peek_user(target, pos), u++))
911 return -EFAULT;
912 count -= sizeof(*u);
913 pos += sizeof(*u);
914 }
915 }
916 return 0;
917}
918
919static int s390_regs_set(struct task_struct *target,
920 const struct user_regset *regset,
921 unsigned int pos, unsigned int count,
922 const void *kbuf, const void __user *ubuf)
923{
924 int rc = 0;
925
926 if (target == current)
927 save_access_regs(target->thread.acrs);
928
929 if (kbuf) {
930 const unsigned long *k = kbuf;
931 while (count > 0 && !rc) {
932 rc = __poke_user(target, pos, *k++);
933 count -= sizeof(*k);
934 pos += sizeof(*k);
935 }
936 } else {
937 const unsigned long __user *u = ubuf;
938 while (count > 0 && !rc) {
939 unsigned long word;
940 rc = __get_user(word, u++);
941 if (rc)
942 break;
943 rc = __poke_user(target, pos, word);
944 count -= sizeof(*u);
945 pos += sizeof(*u);
946 }
947 }
948
949 if (rc == 0 && target == current)
950 restore_access_regs(target->thread.acrs);
951
952 return rc;
953}
954
955static int s390_fpregs_get(struct task_struct *target,
956 const struct user_regset *regset, unsigned int pos,
957 unsigned int count, void *kbuf, void __user *ubuf)
958{
959 _s390_fp_regs fp_regs;
960
961 if (target == current)
962 save_fpu_regs();
963
964 fp_regs.fpc = target->thread.fpu.fpc;
965 fpregs_store(&fp_regs, &target->thread.fpu);
966
967 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
968 &fp_regs, 0, -1);
969}
970
971static int s390_fpregs_set(struct task_struct *target,
972 const struct user_regset *regset, unsigned int pos,
973 unsigned int count, const void *kbuf,
974 const void __user *ubuf)
975{
976 int rc = 0;
977 freg_t fprs[__NUM_FPRS];
978
979 if (target == current)
980 save_fpu_regs();
981
982 if (MACHINE_HAS_VX)
983 convert_vx_to_fp(fprs, target->thread.fpu.vxrs);
984 else
985 memcpy(&fprs, target->thread.fpu.fprs, sizeof(fprs));
986
987 /* If setting FPC, must validate it first. */
988 if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
989 u32 ufpc[2] = { target->thread.fpu.fpc, 0 };
990 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
991 0, offsetof(s390_fp_regs, fprs));
992 if (rc)
993 return rc;
994 if (ufpc[1] != 0 || test_fp_ctl(ufpc[0]))
995 return -EINVAL;
996 target->thread.fpu.fpc = ufpc[0];
997 }
998
999 if (rc == 0 && count > 0)
1000 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1001 fprs, offsetof(s390_fp_regs, fprs), -1);
1002 if (rc)
1003 return rc;
1004
1005 if (MACHINE_HAS_VX)
1006 convert_fp_to_vx(target->thread.fpu.vxrs, fprs);
1007 else
1008 memcpy(target->thread.fpu.fprs, &fprs, sizeof(fprs));
1009
1010 return rc;
1011}
1012
1013static int s390_last_break_get(struct task_struct *target,
1014 const struct user_regset *regset,
1015 unsigned int pos, unsigned int count,
1016 void *kbuf, void __user *ubuf)
1017{
1018 if (count > 0) {
1019 if (kbuf) {
1020 unsigned long *k = kbuf;
1021 *k = target->thread.last_break;
1022 } else {
1023 unsigned long __user *u = ubuf;
1024 if (__put_user(target->thread.last_break, u))
1025 return -EFAULT;
1026 }
1027 }
1028 return 0;
1029}
1030
1031static int s390_last_break_set(struct task_struct *target,
1032 const struct user_regset *regset,
1033 unsigned int pos, unsigned int count,
1034 const void *kbuf, const void __user *ubuf)
1035{
1036 return 0;
1037}
1038
1039static int s390_tdb_get(struct task_struct *target,
1040 const struct user_regset *regset,
1041 unsigned int pos, unsigned int count,
1042 void *kbuf, void __user *ubuf)
1043{
1044 struct pt_regs *regs = task_pt_regs(target);
1045 unsigned char *data;
1046
1047 if (!(regs->int_code & 0x200))
1048 return -ENODATA;
1049 data = target->thread.trap_tdb;
1050 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, data, 0, 256);
1051}
1052
1053static int s390_tdb_set(struct task_struct *target,
1054 const struct user_regset *regset,
1055 unsigned int pos, unsigned int count,
1056 const void *kbuf, const void __user *ubuf)
1057{
1058 return 0;
1059}
1060
1061static int s390_vxrs_low_get(struct task_struct *target,
1062 const struct user_regset *regset,
1063 unsigned int pos, unsigned int count,
1064 void *kbuf, void __user *ubuf)
1065{
1066 __u64 vxrs[__NUM_VXRS_LOW];
1067 int i;
1068
1069 if (!MACHINE_HAS_VX)
1070 return -ENODEV;
1071 if (target == current)
1072 save_fpu_regs();
1073 for (i = 0; i < __NUM_VXRS_LOW; i++)
1074 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1075 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1076}
1077
1078static int s390_vxrs_low_set(struct task_struct *target,
1079 const struct user_regset *regset,
1080 unsigned int pos, unsigned int count,
1081 const void *kbuf, const void __user *ubuf)
1082{
1083 __u64 vxrs[__NUM_VXRS_LOW];
1084 int i, rc;
1085
1086 if (!MACHINE_HAS_VX)
1087 return -ENODEV;
1088 if (target == current)
1089 save_fpu_regs();
1090
1091 for (i = 0; i < __NUM_VXRS_LOW; i++)
1092 vxrs[i] = *((__u64 *)(target->thread.fpu.vxrs + i) + 1);
1093
1094 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1095 if (rc == 0)
1096 for (i = 0; i < __NUM_VXRS_LOW; i++)
1097 *((__u64 *)(target->thread.fpu.vxrs + i) + 1) = vxrs[i];
1098
1099 return rc;
1100}
1101
1102static int s390_vxrs_high_get(struct task_struct *target,
1103 const struct user_regset *regset,
1104 unsigned int pos, unsigned int count,
1105 void *kbuf, void __user *ubuf)
1106{
1107 __vector128 vxrs[__NUM_VXRS_HIGH];
1108
1109 if (!MACHINE_HAS_VX)
1110 return -ENODEV;
1111 if (target == current)
1112 save_fpu_regs();
1113 memcpy(vxrs, target->thread.fpu.vxrs + __NUM_VXRS_LOW, sizeof(vxrs));
1114
1115 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
1116}
1117
1118static int s390_vxrs_high_set(struct task_struct *target,
1119 const struct user_regset *regset,
1120 unsigned int pos, unsigned int count,
1121 const void *kbuf, const void __user *ubuf)
1122{
1123 int rc;
1124
1125 if (!MACHINE_HAS_VX)
1126 return -ENODEV;
1127 if (target == current)
1128 save_fpu_regs();
1129
1130 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1131 target->thread.fpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1132 return rc;
1133}
1134
1135static int s390_system_call_get(struct task_struct *target,
1136 const struct user_regset *regset,
1137 unsigned int pos, unsigned int count,
1138 void *kbuf, void __user *ubuf)
1139{
1140 unsigned int *data = &target->thread.system_call;
1141 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1142 data, 0, sizeof(unsigned int));
1143}
1144
1145static int s390_system_call_set(struct task_struct *target,
1146 const struct user_regset *regset,
1147 unsigned int pos, unsigned int count,
1148 const void *kbuf, const void __user *ubuf)
1149{
1150 unsigned int *data = &target->thread.system_call;
1151 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1152 data, 0, sizeof(unsigned int));
1153}
1154
1155static int s390_gs_cb_get(struct task_struct *target,
1156 const struct user_regset *regset,
1157 unsigned int pos, unsigned int count,
1158 void *kbuf, void __user *ubuf)
1159{
1160 struct gs_cb *data = target->thread.gs_cb;
1161
1162 if (!MACHINE_HAS_GS)
1163 return -ENODEV;
1164 if (!data)
1165 return -ENODATA;
1166 if (target == current)
1167 save_gs_cb(data);
1168 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1169 data, 0, sizeof(struct gs_cb));
1170}
1171
1172static int s390_gs_cb_set(struct task_struct *target,
1173 const struct user_regset *regset,
1174 unsigned int pos, unsigned int count,
1175 const void *kbuf, const void __user *ubuf)
1176{
1177 struct gs_cb gs_cb = { }, *data = NULL;
1178 int rc;
1179
1180 if (!MACHINE_HAS_GS)
1181 return -ENODEV;
1182 if (!target->thread.gs_cb) {
1183 data = kzalloc(sizeof(*data), GFP_KERNEL);
1184 if (!data)
1185 return -ENOMEM;
1186 }
1187 if (!target->thread.gs_cb)
1188 gs_cb.gsd = 25;
1189 else if (target == current)
1190 save_gs_cb(&gs_cb);
1191 else
1192 gs_cb = *target->thread.gs_cb;
1193 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1194 &gs_cb, 0, sizeof(gs_cb));
1195 if (rc) {
1196 kfree(data);
1197 return -EFAULT;
1198 }
1199 preempt_disable();
1200 if (!target->thread.gs_cb)
1201 target->thread.gs_cb = data;
1202 *target->thread.gs_cb = gs_cb;
1203 if (target == current) {
1204 __ctl_set_bit(2, 4);
1205 restore_gs_cb(target->thread.gs_cb);
1206 }
1207 preempt_enable();
1208 return rc;
1209}
1210
1211static int s390_gs_bc_get(struct task_struct *target,
1212 const struct user_regset *regset,
1213 unsigned int pos, unsigned int count,
1214 void *kbuf, void __user *ubuf)
1215{
1216 struct gs_cb *data = target->thread.gs_bc_cb;
1217
1218 if (!MACHINE_HAS_GS)
1219 return -ENODEV;
1220 if (!data)
1221 return -ENODATA;
1222 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1223 data, 0, sizeof(struct gs_cb));
1224}
1225
1226static int s390_gs_bc_set(struct task_struct *target,
1227 const struct user_regset *regset,
1228 unsigned int pos, unsigned int count,
1229 const void *kbuf, const void __user *ubuf)
1230{
1231 struct gs_cb *data = target->thread.gs_bc_cb;
1232
1233 if (!MACHINE_HAS_GS)
1234 return -ENODEV;
1235 if (!data) {
1236 data = kzalloc(sizeof(*data), GFP_KERNEL);
1237 if (!data)
1238 return -ENOMEM;
1239 target->thread.gs_bc_cb = data;
1240 }
1241 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1242 data, 0, sizeof(struct gs_cb));
1243}
1244
1245static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1246{
1247 return (cb->rca & 0x1f) == 0 &&
1248 (cb->roa & 0xfff) == 0 &&
1249 (cb->rla & 0xfff) == 0xfff &&
1250 cb->s == 1 &&
1251 cb->k == 1 &&
1252 cb->h == 0 &&
1253 cb->reserved1 == 0 &&
1254 cb->ps == 1 &&
1255 cb->qs == 0 &&
1256 cb->pc == 1 &&
1257 cb->qc == 0 &&
1258 cb->reserved2 == 0 &&
1259 cb->key == PAGE_DEFAULT_KEY &&
1260 cb->reserved3 == 0 &&
1261 cb->reserved4 == 0 &&
1262 cb->reserved5 == 0 &&
1263 cb->reserved6 == 0 &&
1264 cb->reserved7 == 0 &&
1265 cb->reserved8 == 0 &&
1266 cb->rla >= cb->roa &&
1267 cb->rca >= cb->roa &&
1268 cb->rca <= cb->rla+1 &&
1269 cb->m < 3;
1270}
1271
1272static int s390_runtime_instr_get(struct task_struct *target,
1273 const struct user_regset *regset,
1274 unsigned int pos, unsigned int count,
1275 void *kbuf, void __user *ubuf)
1276{
1277 struct runtime_instr_cb *data = target->thread.ri_cb;
1278
1279 if (!test_facility(64))
1280 return -ENODEV;
1281 if (!data)
1282 return -ENODATA;
1283
1284 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
1285 data, 0, sizeof(struct runtime_instr_cb));
1286}
1287
1288static int s390_runtime_instr_set(struct task_struct *target,
1289 const struct user_regset *regset,
1290 unsigned int pos, unsigned int count,
1291 const void *kbuf, const void __user *ubuf)
1292{
1293 struct runtime_instr_cb ri_cb = { }, *data = NULL;
1294 int rc;
1295
1296 if (!test_facility(64))
1297 return -ENODEV;
1298
1299 if (!target->thread.ri_cb) {
1300 data = kzalloc(sizeof(*data), GFP_KERNEL);
1301 if (!data)
1302 return -ENOMEM;
1303 }
1304
1305 if (target->thread.ri_cb) {
1306 if (target == current)
1307 store_runtime_instr_cb(&ri_cb);
1308 else
1309 ri_cb = *target->thread.ri_cb;
1310 }
1311
1312 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1313 &ri_cb, 0, sizeof(struct runtime_instr_cb));
1314 if (rc) {
1315 kfree(data);
1316 return -EFAULT;
1317 }
1318
1319 if (!is_ri_cb_valid(&ri_cb)) {
1320 kfree(data);
1321 return -EINVAL;
1322 }
1323
1324 preempt_disable();
1325 if (!target->thread.ri_cb)
1326 target->thread.ri_cb = data;
1327 *target->thread.ri_cb = ri_cb;
1328 if (target == current)
1329 load_runtime_instr_cb(target->thread.ri_cb);
1330 preempt_enable();
1331
1332 return 0;
1333}
1334
1335static const struct user_regset s390_regsets[] = {
1336 {
1337 .core_note_type = NT_PRSTATUS,
1338 .n = sizeof(s390_regs) / sizeof(long),
1339 .size = sizeof(long),
1340 .align = sizeof(long),
1341 .get = s390_regs_get,
1342 .set = s390_regs_set,
1343 },
1344 {
1345 .core_note_type = NT_PRFPREG,
1346 .n = sizeof(s390_fp_regs) / sizeof(long),
1347 .size = sizeof(long),
1348 .align = sizeof(long),
1349 .get = s390_fpregs_get,
1350 .set = s390_fpregs_set,
1351 },
1352 {
1353 .core_note_type = NT_S390_SYSTEM_CALL,
1354 .n = 1,
1355 .size = sizeof(unsigned int),
1356 .align = sizeof(unsigned int),
1357 .get = s390_system_call_get,
1358 .set = s390_system_call_set,
1359 },
1360 {
1361 .core_note_type = NT_S390_LAST_BREAK,
1362 .n = 1,
1363 .size = sizeof(long),
1364 .align = sizeof(long),
1365 .get = s390_last_break_get,
1366 .set = s390_last_break_set,
1367 },
1368 {
1369 .core_note_type = NT_S390_TDB,
1370 .n = 1,
1371 .size = 256,
1372 .align = 1,
1373 .get = s390_tdb_get,
1374 .set = s390_tdb_set,
1375 },
1376 {
1377 .core_note_type = NT_S390_VXRS_LOW,
1378 .n = __NUM_VXRS_LOW,
1379 .size = sizeof(__u64),
1380 .align = sizeof(__u64),
1381 .get = s390_vxrs_low_get,
1382 .set = s390_vxrs_low_set,
1383 },
1384 {
1385 .core_note_type = NT_S390_VXRS_HIGH,
1386 .n = __NUM_VXRS_HIGH,
1387 .size = sizeof(__vector128),
1388 .align = sizeof(__vector128),
1389 .get = s390_vxrs_high_get,
1390 .set = s390_vxrs_high_set,
1391 },
1392 {
1393 .core_note_type = NT_S390_GS_CB,
1394 .n = sizeof(struct gs_cb) / sizeof(__u64),
1395 .size = sizeof(__u64),
1396 .align = sizeof(__u64),
1397 .get = s390_gs_cb_get,
1398 .set = s390_gs_cb_set,
1399 },
1400 {
1401 .core_note_type = NT_S390_GS_BC,
1402 .n = sizeof(struct gs_cb) / sizeof(__u64),
1403 .size = sizeof(__u64),
1404 .align = sizeof(__u64),
1405 .get = s390_gs_bc_get,
1406 .set = s390_gs_bc_set,
1407 },
1408 {
1409 .core_note_type = NT_S390_RI_CB,
1410 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1411 .size = sizeof(__u64),
1412 .align = sizeof(__u64),
1413 .get = s390_runtime_instr_get,
1414 .set = s390_runtime_instr_set,
1415 },
1416};
1417
1418static const struct user_regset_view user_s390_view = {
1419 .name = UTS_MACHINE,
1420 .e_machine = EM_S390,
1421 .regsets = s390_regsets,
1422 .n = ARRAY_SIZE(s390_regsets)
1423};
1424
1425#ifdef CONFIG_COMPAT
1426static int s390_compat_regs_get(struct task_struct *target,
1427 const struct user_regset *regset,
1428 unsigned int pos, unsigned int count,
1429 void *kbuf, void __user *ubuf)
1430{
1431 if (target == current)
1432 save_access_regs(target->thread.acrs);
1433
1434 if (kbuf) {
1435 compat_ulong_t *k = kbuf;
1436 while (count > 0) {
1437 *k++ = __peek_user_compat(target, pos);
1438 count -= sizeof(*k);
1439 pos += sizeof(*k);
1440 }
1441 } else {
1442 compat_ulong_t __user *u = ubuf;
1443 while (count > 0) {
1444 if (__put_user(__peek_user_compat(target, pos), u++))
1445 return -EFAULT;
1446 count -= sizeof(*u);
1447 pos += sizeof(*u);
1448 }
1449 }
1450 return 0;
1451}
1452
1453static int s390_compat_regs_set(struct task_struct *target,
1454 const struct user_regset *regset,
1455 unsigned int pos, unsigned int count,
1456 const void *kbuf, const void __user *ubuf)
1457{
1458 int rc = 0;
1459
1460 if (target == current)
1461 save_access_regs(target->thread.acrs);
1462
1463 if (kbuf) {
1464 const compat_ulong_t *k = kbuf;
1465 while (count > 0 && !rc) {
1466 rc = __poke_user_compat(target, pos, *k++);
1467 count -= sizeof(*k);
1468 pos += sizeof(*k);
1469 }
1470 } else {
1471 const compat_ulong_t __user *u = ubuf;
1472 while (count > 0 && !rc) {
1473 compat_ulong_t word;
1474 rc = __get_user(word, u++);
1475 if (rc)
1476 break;
1477 rc = __poke_user_compat(target, pos, word);
1478 count -= sizeof(*u);
1479 pos += sizeof(*u);
1480 }
1481 }
1482
1483 if (rc == 0 && target == current)
1484 restore_access_regs(target->thread.acrs);
1485
1486 return rc;
1487}
1488
1489static int s390_compat_regs_high_get(struct task_struct *target,
1490 const struct user_regset *regset,
1491 unsigned int pos, unsigned int count,
1492 void *kbuf, void __user *ubuf)
1493{
1494 compat_ulong_t *gprs_high;
1495
1496 gprs_high = (compat_ulong_t *)
1497 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1498 if (kbuf) {
1499 compat_ulong_t *k = kbuf;
1500 while (count > 0) {
1501 *k++ = *gprs_high;
1502 gprs_high += 2;
1503 count -= sizeof(*k);
1504 }
1505 } else {
1506 compat_ulong_t __user *u = ubuf;
1507 while (count > 0) {
1508 if (__put_user(*gprs_high, u++))
1509 return -EFAULT;
1510 gprs_high += 2;
1511 count -= sizeof(*u);
1512 }
1513 }
1514 return 0;
1515}
1516
1517static int s390_compat_regs_high_set(struct task_struct *target,
1518 const struct user_regset *regset,
1519 unsigned int pos, unsigned int count,
1520 const void *kbuf, const void __user *ubuf)
1521{
1522 compat_ulong_t *gprs_high;
1523 int rc = 0;
1524
1525 gprs_high = (compat_ulong_t *)
1526 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1527 if (kbuf) {
1528 const compat_ulong_t *k = kbuf;
1529 while (count > 0) {
1530 *gprs_high = *k++;
1531 *gprs_high += 2;
1532 count -= sizeof(*k);
1533 }
1534 } else {
1535 const compat_ulong_t __user *u = ubuf;
1536 while (count > 0 && !rc) {
1537 unsigned long word;
1538 rc = __get_user(word, u++);
1539 if (rc)
1540 break;
1541 *gprs_high = word;
1542 *gprs_high += 2;
1543 count -= sizeof(*u);
1544 }
1545 }
1546
1547 return rc;
1548}
1549
1550static int s390_compat_last_break_get(struct task_struct *target,
1551 const struct user_regset *regset,
1552 unsigned int pos, unsigned int count,
1553 void *kbuf, void __user *ubuf)
1554{
1555 compat_ulong_t last_break;
1556
1557 if (count > 0) {
1558 last_break = target->thread.last_break;
1559 if (kbuf) {
1560 unsigned long *k = kbuf;
1561 *k = last_break;
1562 } else {
1563 unsigned long __user *u = ubuf;
1564 if (__put_user(last_break, u))
1565 return -EFAULT;
1566 }
1567 }
1568 return 0;
1569}
1570
1571static int s390_compat_last_break_set(struct task_struct *target,
1572 const struct user_regset *regset,
1573 unsigned int pos, unsigned int count,
1574 const void *kbuf, const void __user *ubuf)
1575{
1576 return 0;
1577}
1578
1579static const struct user_regset s390_compat_regsets[] = {
1580 {
1581 .core_note_type = NT_PRSTATUS,
1582 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1583 .size = sizeof(compat_long_t),
1584 .align = sizeof(compat_long_t),
1585 .get = s390_compat_regs_get,
1586 .set = s390_compat_regs_set,
1587 },
1588 {
1589 .core_note_type = NT_PRFPREG,
1590 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1591 .size = sizeof(compat_long_t),
1592 .align = sizeof(compat_long_t),
1593 .get = s390_fpregs_get,
1594 .set = s390_fpregs_set,
1595 },
1596 {
1597 .core_note_type = NT_S390_SYSTEM_CALL,
1598 .n = 1,
1599 .size = sizeof(compat_uint_t),
1600 .align = sizeof(compat_uint_t),
1601 .get = s390_system_call_get,
1602 .set = s390_system_call_set,
1603 },
1604 {
1605 .core_note_type = NT_S390_LAST_BREAK,
1606 .n = 1,
1607 .size = sizeof(long),
1608 .align = sizeof(long),
1609 .get = s390_compat_last_break_get,
1610 .set = s390_compat_last_break_set,
1611 },
1612 {
1613 .core_note_type = NT_S390_TDB,
1614 .n = 1,
1615 .size = 256,
1616 .align = 1,
1617 .get = s390_tdb_get,
1618 .set = s390_tdb_set,
1619 },
1620 {
1621 .core_note_type = NT_S390_VXRS_LOW,
1622 .n = __NUM_VXRS_LOW,
1623 .size = sizeof(__u64),
1624 .align = sizeof(__u64),
1625 .get = s390_vxrs_low_get,
1626 .set = s390_vxrs_low_set,
1627 },
1628 {
1629 .core_note_type = NT_S390_VXRS_HIGH,
1630 .n = __NUM_VXRS_HIGH,
1631 .size = sizeof(__vector128),
1632 .align = sizeof(__vector128),
1633 .get = s390_vxrs_high_get,
1634 .set = s390_vxrs_high_set,
1635 },
1636 {
1637 .core_note_type = NT_S390_HIGH_GPRS,
1638 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1639 .size = sizeof(compat_long_t),
1640 .align = sizeof(compat_long_t),
1641 .get = s390_compat_regs_high_get,
1642 .set = s390_compat_regs_high_set,
1643 },
1644 {
1645 .core_note_type = NT_S390_GS_CB,
1646 .n = sizeof(struct gs_cb) / sizeof(__u64),
1647 .size = sizeof(__u64),
1648 .align = sizeof(__u64),
1649 .get = s390_gs_cb_get,
1650 .set = s390_gs_cb_set,
1651 },
1652 {
1653 .core_note_type = NT_S390_GS_BC,
1654 .n = sizeof(struct gs_cb) / sizeof(__u64),
1655 .size = sizeof(__u64),
1656 .align = sizeof(__u64),
1657 .get = s390_gs_bc_get,
1658 .set = s390_gs_bc_set,
1659 },
1660 {
1661 .core_note_type = NT_S390_RI_CB,
1662 .n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1663 .size = sizeof(__u64),
1664 .align = sizeof(__u64),
1665 .get = s390_runtime_instr_get,
1666 .set = s390_runtime_instr_set,
1667 },
1668};
1669
1670static const struct user_regset_view user_s390_compat_view = {
1671 .name = "s390",
1672 .e_machine = EM_S390,
1673 .regsets = s390_compat_regsets,
1674 .n = ARRAY_SIZE(s390_compat_regsets)
1675};
1676#endif
1677
1678const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1679{
1680#ifdef CONFIG_COMPAT
1681 if (test_tsk_thread_flag(task, TIF_31BIT))
1682 return &user_s390_compat_view;
1683#endif
1684 return &user_s390_view;
1685}
1686
1687static const char *gpr_names[NUM_GPRS] = {
1688 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
1689 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1690};
1691
1692unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1693{
1694 if (offset >= NUM_GPRS)
1695 return 0;
1696 return regs->gprs[offset];
1697}
1698
1699int regs_query_register_offset(const char *name)
1700{
1701 unsigned long offset;
1702
1703 if (!name || *name != 'r')
1704 return -EINVAL;
1705 if (kstrtoul(name + 1, 10, &offset))
1706 return -EINVAL;
1707 if (offset >= NUM_GPRS)
1708 return -EINVAL;
1709 return offset;
1710}
1711
1712const char *regs_query_register_name(unsigned int offset)
1713{
1714 if (offset >= NUM_GPRS)
1715 return NULL;
1716 return gpr_names[offset];
1717}
1718
1719static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1720{
1721 unsigned long ksp = kernel_stack_pointer(regs);
1722
1723 return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1724}
1725
1726/**
1727 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1728 * @regs:pt_regs which contains kernel stack pointer.
1729 * @n:stack entry number.
1730 *
1731 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1732 * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1733 * this returns 0.
1734 */
1735unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1736{
1737 unsigned long addr;
1738
1739 addr = kernel_stack_pointer(regs) + n * sizeof(long);
1740 if (!regs_within_kernel_stack(regs, addr))
1741 return 0;
1742 return *(unsigned long *)addr;
1743}