1 // SPDX-License-Identifier: GPL-2.0
3 * Kernel support for the ptrace() and syscall tracing interfaces.
5 * Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc.
6 * Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx>
7 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
8 * Copyright (C) 2008-2016 Helge Deller <deller@gmx.de>
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
14 #include <linux/smp.h>
15 #include <linux/elf.h>
16 #include <linux/errno.h>
17 #include <linux/ptrace.h>
18 #include <linux/tracehook.h>
19 #include <linux/user.h>
20 #include <linux/personality.h>
21 #include <linux/regset.h>
22 #include <linux/security.h>
23 #include <linux/seccomp.h>
24 #include <linux/compat.h>
25 #include <linux/signal.h>
26 #include <linux/audit.h>
28 #include <linux/uaccess.h>
29 #include <asm/pgtable.h>
30 #include <asm/processor.h>
31 #include <asm/asm-offsets.h>
33 /* PSW bits we allow the debugger to modify */
34 #define USER_PSW_BITS (PSW_N | PSW_B | PSW_V | PSW_CB)
36 #define CREATE_TRACE_POINTS
37 #include <trace/events/syscalls.h>
40 * These are our native regset flavors.
48 * Called by kernel/ptrace.c when detaching..
50 * Make sure single step bits etc are not set.
52 void ptrace_disable(struct task_struct *task)
54 clear_tsk_thread_flag(task, TIF_SINGLESTEP);
55 clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
57 /* make sure the trap bits are not set */
65 * The following functions are called by ptrace_resume() when
66 * enabling or disabling single/block tracing.
68 void user_disable_single_step(struct task_struct *task)
73 void user_enable_single_step(struct task_struct *task)
75 clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
76 set_tsk_thread_flag(task, TIF_SINGLESTEP);
78 if (pa_psw(task)->n) {
79 /* Nullified, just crank over the queue. */
80 task_regs(task)->iaoq[0] = task_regs(task)->iaoq[1];
81 task_regs(task)->iasq[0] = task_regs(task)->iasq[1];
82 task_regs(task)->iaoq[1] = task_regs(task)->iaoq[0] + 4;
89 /* Don't wake up the task, but let the
90 parent know something happened. */
91 force_sig_fault_to_task(SIGTRAP, TRAP_TRACE,
92 (void __user *) (task_regs(task)->iaoq[0] & ~3),
94 /* notify_parent(task, SIGCHLD); */
98 /* Enable recovery counter traps. The recovery counter
99 * itself will be set to zero on a task switch. If the
100 * task is suspended on a syscall then the syscall return
101 * path will overwrite the recovery counter with a suitable
102 * value such that it traps once back in user space. We
103 * disable interrupts in the tasks PSW here also, to avoid
104 * interrupts while the recovery counter is decrementing.
112 void user_enable_block_step(struct task_struct *task)
114 clear_tsk_thread_flag(task, TIF_SINGLESTEP);
115 set_tsk_thread_flag(task, TIF_BLOCKSTEP);
117 /* Enable taken branch trap. */
124 long arch_ptrace(struct task_struct *child, long request,
125 unsigned long addr, unsigned long data)
127 unsigned long __user *datap = (unsigned long __user *)data;
131 unsigned long user_regs_struct_size = sizeof(struct user_regs_struct);
133 if (is_compat_task())
134 user_regs_struct_size /= 2;
139 /* Read the word at location addr in the USER area. For ptraced
140 processes, the kernel saves all regs on a syscall. */
142 if ((addr & (sizeof(unsigned long)-1)) ||
143 addr >= sizeof(struct pt_regs))
145 tmp = *(unsigned long *) ((char *) task_regs(child) + addr);
146 ret = put_user(tmp, datap);
149 /* Write the word at location addr in the USER area. This will need
150 to change when the kernel no longer saves all regs on a syscall.
151 FIXME. There is a problem at the moment in that r3-r18 are only
152 saved if the process is ptraced on syscall entry, and even then
153 those values are overwritten by actual register values on syscall
156 /* Some register values written here may be ignored in
157 * entry.S:syscall_restore_rfi; e.g. iaoq is written with
158 * r31/r31+4, and not with the values in pt_regs.
160 if (addr == PT_PSW) {
161 /* Allow writing to Nullify, Divide-step-correction,
162 * and carry/borrow bits.
163 * BEWARE, if you set N, and then single step, it won't
164 * stop on the nullified instruction.
166 data &= USER_PSW_BITS;
167 task_regs(child)->gr[0] &= ~USER_PSW_BITS;
168 task_regs(child)->gr[0] |= data;
173 if ((addr & (sizeof(unsigned long)-1)) ||
174 addr >= sizeof(struct pt_regs))
176 if (addr == PT_IAOQ0 || addr == PT_IAOQ1) {
177 data |= 3; /* ensure userspace privilege */
179 if ((addr >= PT_GR1 && addr <= PT_GR31) ||
180 addr == PT_IAOQ0 || addr == PT_IAOQ1 ||
181 (addr >= PT_FR0 && addr <= PT_FR31 + 4) ||
183 *(unsigned long *) ((char *) task_regs(child) + addr) = data;
188 case PTRACE_GETREGS: /* Get all gp regs from the child. */
189 return copy_regset_to_user(child,
190 task_user_regset_view(current),
192 0, user_regs_struct_size,
195 case PTRACE_SETREGS: /* Set all gp regs in the child. */
196 return copy_regset_from_user(child,
197 task_user_regset_view(current),
199 0, user_regs_struct_size,
202 case PTRACE_GETFPREGS: /* Get the child FPU state. */
203 return copy_regset_to_user(child,
204 task_user_regset_view(current),
206 0, sizeof(struct user_fp_struct),
209 case PTRACE_SETFPREGS: /* Set the child FPU state. */
210 return copy_regset_from_user(child,
211 task_user_regset_view(current),
213 0, sizeof(struct user_fp_struct),
217 ret = ptrace_request(child, request, addr, data);
227 /* This function is needed to translate 32 bit pt_regs offsets in to
228 * 64 bit pt_regs offsets. For example, a 32 bit gdb under a 64 bit kernel
229 * will request offset 12 if it wants gr3, but the lower 32 bits of
230 * the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4).
231 * This code relies on a 32 bit pt_regs being comprised of 32 bit values
232 * except for the fp registers which (a) are 64 bits, and (b) follow
233 * the gr registers at the start of pt_regs. The 32 bit pt_regs should
234 * be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[]
235 * being 64 bit in both cases.
238 static compat_ulong_t translate_usr_offset(compat_ulong_t offset)
242 if (offset < 32*4) /* gr[0..31] */
243 pos = offset * 2 + 4;
244 else if (offset < 32*4+32*8) /* fr[0] ... fr[31] */
245 pos = (offset - 32*4) + PT_FR0;
246 else if (offset < sizeof(struct pt_regs)/2 + 32*4) /* sr[0] ... ipsw */
247 pos = (offset - 32*4 - 32*8) * 2 + PT_SR0 + 4;
249 pos = sizeof(struct pt_regs);
254 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
255 compat_ulong_t addr, compat_ulong_t data)
263 if (addr & (sizeof(compat_uint_t)-1))
265 addr = translate_usr_offset(addr);
266 if (addr >= sizeof(struct pt_regs))
269 tmp = *(compat_uint_t *) ((char *) task_regs(child) + addr);
270 ret = put_user(tmp, (compat_uint_t *) (unsigned long) data);
273 /* Write the word at location addr in the USER area. This will need
274 to change when the kernel no longer saves all regs on a syscall.
275 FIXME. There is a problem at the moment in that r3-r18 are only
276 saved if the process is ptraced on syscall entry, and even then
277 those values are overwritten by actual register values on syscall
280 /* Some register values written here may be ignored in
281 * entry.S:syscall_restore_rfi; e.g. iaoq is written with
282 * r31/r31+4, and not with the values in pt_regs.
284 if (addr == PT_PSW) {
285 /* Since PT_PSW==0, it is valid for 32 bit processes
286 * under 64 bit kernels as well.
288 ret = arch_ptrace(child, request, addr, data);
290 if (addr & (sizeof(compat_uint_t)-1))
292 addr = translate_usr_offset(addr);
293 if (addr >= sizeof(struct pt_regs))
295 if (addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4) {
296 data |= 3; /* ensure userspace privilege */
298 if (addr >= PT_FR0 && addr <= PT_FR31 + 4) {
299 /* Special case, fp regs are 64 bits anyway */
300 *(__u32 *) ((char *) task_regs(child) + addr) = data;
303 else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) ||
304 addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4 ||
306 /* Zero the top 32 bits */
307 *(__u32 *) ((char *) task_regs(child) + addr - 4) = 0;
308 *(__u32 *) ((char *) task_regs(child) + addr) = data;
315 case PTRACE_GETFPREGS:
316 case PTRACE_SETFPREGS:
317 return arch_ptrace(child, request, addr, data);
320 ret = compat_ptrace_request(child, request, addr, data);
328 long do_syscall_trace_enter(struct pt_regs *regs)
330 if (test_thread_flag(TIF_SYSCALL_TRACE)) {
331 int rc = tracehook_report_syscall_entry(regs);
334 * As tracesys_next does not set %r28 to -ENOSYS
335 * when %r20 is set to -1, initialize it here.
337 regs->gr[28] = -ENOSYS;
341 * A nonzero return code from
342 * tracehook_report_syscall_entry() tells us
343 * to prevent the syscall execution. Skip
344 * the syscall call and the syscall restart handling.
346 * Note that the tracer may also just change
347 * regs->gr[20] to an invalid syscall number,
348 * that is handled by tracesys_next.
355 /* Do the secure computing check after ptrace. */
356 if (secure_computing(NULL) == -1)
359 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
360 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
361 trace_sys_enter(regs, regs->gr[20]);
365 if (!is_compat_task())
366 audit_syscall_entry(regs->gr[20], regs->gr[26], regs->gr[25],
367 regs->gr[24], regs->gr[23]);
370 audit_syscall_entry(regs->gr[20] & 0xffffffff,
371 regs->gr[26] & 0xffffffff,
372 regs->gr[25] & 0xffffffff,
373 regs->gr[24] & 0xffffffff,
374 regs->gr[23] & 0xffffffff);
377 * Sign extend the syscall number to 64bit since it may have been
378 * modified by a compat ptrace call
380 return (int) ((u32) regs->gr[20]);
383 void do_syscall_trace_exit(struct pt_regs *regs)
385 int stepping = test_thread_flag(TIF_SINGLESTEP) ||
386 test_thread_flag(TIF_BLOCKSTEP);
388 audit_syscall_exit(regs);
390 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
391 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
392 trace_sys_exit(regs, regs->gr[20]);
395 if (stepping || test_thread_flag(TIF_SYSCALL_TRACE))
396 tracehook_report_syscall_exit(regs, stepping);
404 static int fpr_get(struct task_struct *target,
405 const struct user_regset *regset,
406 unsigned int pos, unsigned int count,
407 void *kbuf, void __user *ubuf)
409 struct pt_regs *regs = task_regs(target);
411 __u64 __user *u = ubuf;
415 count /= sizeof(reg);
418 for (; count > 0 && pos < ELF_NFPREG; --count)
419 *k++ = regs->fr[pos++];
421 for (; count > 0 && pos < ELF_NFPREG; --count)
422 if (__put_user(regs->fr[pos++], u++))
428 count *= sizeof(reg);
429 return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
430 ELF_NFPREG * sizeof(reg), -1);
433 static int fpr_set(struct task_struct *target,
434 const struct user_regset *regset,
435 unsigned int pos, unsigned int count,
436 const void *kbuf, const void __user *ubuf)
438 struct pt_regs *regs = task_regs(target);
439 const __u64 *k = kbuf;
440 const __u64 __user *u = ubuf;
444 count /= sizeof(reg);
447 for (; count > 0 && pos < ELF_NFPREG; --count)
448 regs->fr[pos++] = *k++;
450 for (; count > 0 && pos < ELF_NFPREG; --count) {
451 if (__get_user(reg, u++))
453 regs->fr[pos++] = reg;
459 count *= sizeof(reg);
460 return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
461 ELF_NFPREG * sizeof(reg), -1);
464 #define RI(reg) (offsetof(struct user_regs_struct,reg) / sizeof(long))
466 static unsigned long get_reg(struct pt_regs *regs, int num)
469 case RI(gr[0]) ... RI(gr[31]): return regs->gr[num - RI(gr[0])];
470 case RI(sr[0]) ... RI(sr[7]): return regs->sr[num - RI(sr[0])];
471 case RI(iasq[0]): return regs->iasq[0];
472 case RI(iasq[1]): return regs->iasq[1];
473 case RI(iaoq[0]): return regs->iaoq[0];
474 case RI(iaoq[1]): return regs->iaoq[1];
475 case RI(sar): return regs->sar;
476 case RI(iir): return regs->iir;
477 case RI(isr): return regs->isr;
478 case RI(ior): return regs->ior;
479 case RI(ipsw): return regs->ipsw;
480 case RI(cr27): return regs->cr27;
481 case RI(cr0): return mfctl(0);
482 case RI(cr24): return mfctl(24);
483 case RI(cr25): return mfctl(25);
484 case RI(cr26): return mfctl(26);
485 case RI(cr28): return mfctl(28);
486 case RI(cr29): return mfctl(29);
487 case RI(cr30): return mfctl(30);
488 case RI(cr31): return mfctl(31);
489 case RI(cr8): return mfctl(8);
490 case RI(cr9): return mfctl(9);
491 case RI(cr12): return mfctl(12);
492 case RI(cr13): return mfctl(13);
493 case RI(cr10): return mfctl(10);
494 case RI(cr15): return mfctl(15);
499 static void set_reg(struct pt_regs *regs, int num, unsigned long val)
504 * Allow writing to Nullify, Divide-step-correction,
505 * and carry/borrow bits.
506 * BEWARE, if you set N, and then single step, it won't
507 * stop on the nullified instruction.
509 val &= USER_PSW_BITS;
510 regs->gr[0] &= ~USER_PSW_BITS;
513 case RI(gr[1]) ... RI(gr[31]):
514 regs->gr[num - RI(gr[0])] = val;
518 /* set 2 lowest bits to ensure userspace privilege: */
519 regs->iaoq[num - RI(iaoq[0])] = val | 3;
521 case RI(sar): regs->sar = val;
525 /* do not allow to change any of the following registers (yet) */
526 case RI(sr[0]) ... RI(sr[7]): return regs->sr[num - RI(sr[0])];
527 case RI(iasq[0]): return regs->iasq[0];
528 case RI(iasq[1]): return regs->iasq[1];
529 case RI(iir): return regs->iir;
530 case RI(isr): return regs->isr;
531 case RI(ior): return regs->ior;
532 case RI(ipsw): return regs->ipsw;
533 case RI(cr27): return regs->cr27;
534 case cr0, cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31;
535 case cr8, cr9, cr12, cr13, cr10, cr15;
540 static int gpr_get(struct task_struct *target,
541 const struct user_regset *regset,
542 unsigned int pos, unsigned int count,
543 void *kbuf, void __user *ubuf)
545 struct pt_regs *regs = task_regs(target);
546 unsigned long *k = kbuf;
547 unsigned long __user *u = ubuf;
551 count /= sizeof(reg);
554 for (; count > 0 && pos < ELF_NGREG; --count)
555 *k++ = get_reg(regs, pos++);
557 for (; count > 0 && pos < ELF_NGREG; --count)
558 if (__put_user(get_reg(regs, pos++), u++))
563 count *= sizeof(reg);
564 return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
565 ELF_NGREG * sizeof(reg), -1);
568 static int gpr_set(struct task_struct *target,
569 const struct user_regset *regset,
570 unsigned int pos, unsigned int count,
571 const void *kbuf, const void __user *ubuf)
573 struct pt_regs *regs = task_regs(target);
574 const unsigned long *k = kbuf;
575 const unsigned long __user *u = ubuf;
579 count /= sizeof(reg);
582 for (; count > 0 && pos < ELF_NGREG; --count)
583 set_reg(regs, pos++, *k++);
585 for (; count > 0 && pos < ELF_NGREG; --count) {
586 if (__get_user(reg, u++))
588 set_reg(regs, pos++, reg);
594 count *= sizeof(reg);
595 return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
596 ELF_NGREG * sizeof(reg), -1);
599 static const struct user_regset native_regsets[] = {
601 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
602 .size = sizeof(long), .align = sizeof(long),
603 .get = gpr_get, .set = gpr_set
606 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
607 .size = sizeof(__u64), .align = sizeof(__u64),
608 .get = fpr_get, .set = fpr_set
612 static const struct user_regset_view user_parisc_native_view = {
613 .name = "parisc", .e_machine = ELF_ARCH, .ei_osabi = ELFOSABI_LINUX,
614 .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
618 #include <linux/compat.h>
620 static int gpr32_get(struct task_struct *target,
621 const struct user_regset *regset,
622 unsigned int pos, unsigned int count,
623 void *kbuf, void __user *ubuf)
625 struct pt_regs *regs = task_regs(target);
626 compat_ulong_t *k = kbuf;
627 compat_ulong_t __user *u = ubuf;
631 count /= sizeof(reg);
634 for (; count > 0 && pos < ELF_NGREG; --count)
635 *k++ = get_reg(regs, pos++);
637 for (; count > 0 && pos < ELF_NGREG; --count)
638 if (__put_user((compat_ulong_t) get_reg(regs, pos++), u++))
644 count *= sizeof(reg);
645 return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
646 ELF_NGREG * sizeof(reg), -1);
649 static int gpr32_set(struct task_struct *target,
650 const struct user_regset *regset,
651 unsigned int pos, unsigned int count,
652 const void *kbuf, const void __user *ubuf)
654 struct pt_regs *regs = task_regs(target);
655 const compat_ulong_t *k = kbuf;
656 const compat_ulong_t __user *u = ubuf;
660 count /= sizeof(reg);
663 for (; count > 0 && pos < ELF_NGREG; --count)
664 set_reg(regs, pos++, *k++);
666 for (; count > 0 && pos < ELF_NGREG; --count) {
667 if (__get_user(reg, u++))
669 set_reg(regs, pos++, reg);
675 count *= sizeof(reg);
676 return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
677 ELF_NGREG * sizeof(reg), -1);
681 * These are the regset flavors matching the 32bit native set.
683 static const struct user_regset compat_regsets[] = {
685 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
686 .size = sizeof(compat_long_t), .align = sizeof(compat_long_t),
687 .get = gpr32_get, .set = gpr32_set
690 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
691 .size = sizeof(__u64), .align = sizeof(__u64),
692 .get = fpr_get, .set = fpr_set
696 static const struct user_regset_view user_parisc_compat_view = {
697 .name = "parisc", .e_machine = EM_PARISC, .ei_osabi = ELFOSABI_LINUX,
698 .regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)
700 #endif /* CONFIG_64BIT */
702 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
704 BUILD_BUG_ON(sizeof(struct user_regs_struct)/sizeof(long) != ELF_NGREG);
705 BUILD_BUG_ON(sizeof(struct user_fp_struct)/sizeof(__u64) != ELF_NFPREG);
707 if (is_compat_task())
708 return &user_parisc_compat_view;
710 return &user_parisc_native_view;
714 /* HAVE_REGS_AND_STACK_ACCESS_API feature */
716 struct pt_regs_offset {
721 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
722 #define REG_OFFSET_INDEX(r,i) {.name = #r#i, .offset = offsetof(struct pt_regs, r[i])}
723 #define REG_OFFSET_END {.name = NULL, .offset = 0}
725 static const struct pt_regs_offset regoffset_table[] = {
726 REG_OFFSET_INDEX(gr,0),
727 REG_OFFSET_INDEX(gr,1),
728 REG_OFFSET_INDEX(gr,2),
729 REG_OFFSET_INDEX(gr,3),
730 REG_OFFSET_INDEX(gr,4),
731 REG_OFFSET_INDEX(gr,5),
732 REG_OFFSET_INDEX(gr,6),
733 REG_OFFSET_INDEX(gr,7),
734 REG_OFFSET_INDEX(gr,8),
735 REG_OFFSET_INDEX(gr,9),
736 REG_OFFSET_INDEX(gr,10),
737 REG_OFFSET_INDEX(gr,11),
738 REG_OFFSET_INDEX(gr,12),
739 REG_OFFSET_INDEX(gr,13),
740 REG_OFFSET_INDEX(gr,14),
741 REG_OFFSET_INDEX(gr,15),
742 REG_OFFSET_INDEX(gr,16),
743 REG_OFFSET_INDEX(gr,17),
744 REG_OFFSET_INDEX(gr,18),
745 REG_OFFSET_INDEX(gr,19),
746 REG_OFFSET_INDEX(gr,20),
747 REG_OFFSET_INDEX(gr,21),
748 REG_OFFSET_INDEX(gr,22),
749 REG_OFFSET_INDEX(gr,23),
750 REG_OFFSET_INDEX(gr,24),
751 REG_OFFSET_INDEX(gr,25),
752 REG_OFFSET_INDEX(gr,26),
753 REG_OFFSET_INDEX(gr,27),
754 REG_OFFSET_INDEX(gr,28),
755 REG_OFFSET_INDEX(gr,29),
756 REG_OFFSET_INDEX(gr,30),
757 REG_OFFSET_INDEX(gr,31),
758 REG_OFFSET_INDEX(sr,0),
759 REG_OFFSET_INDEX(sr,1),
760 REG_OFFSET_INDEX(sr,2),
761 REG_OFFSET_INDEX(sr,3),
762 REG_OFFSET_INDEX(sr,4),
763 REG_OFFSET_INDEX(sr,5),
764 REG_OFFSET_INDEX(sr,6),
765 REG_OFFSET_INDEX(sr,7),
766 REG_OFFSET_INDEX(iasq,0),
767 REG_OFFSET_INDEX(iasq,1),
768 REG_OFFSET_INDEX(iaoq,0),
769 REG_OFFSET_INDEX(iaoq,1),
770 REG_OFFSET_NAME(cr27),
771 REG_OFFSET_NAME(ksp),
772 REG_OFFSET_NAME(kpc),
773 REG_OFFSET_NAME(sar),
774 REG_OFFSET_NAME(iir),
775 REG_OFFSET_NAME(isr),
776 REG_OFFSET_NAME(ior),
777 REG_OFFSET_NAME(ipsw),
782 * regs_query_register_offset() - query register offset from its name
783 * @name: the name of a register
785 * regs_query_register_offset() returns the offset of a register in struct
786 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
788 int regs_query_register_offset(const char *name)
790 const struct pt_regs_offset *roff;
791 for (roff = regoffset_table; roff->name != NULL; roff++)
792 if (!strcmp(roff->name, name))
798 * regs_query_register_name() - query register name from its offset
799 * @offset: the offset of a register in struct pt_regs.
801 * regs_query_register_name() returns the name of a register from its
802 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
804 const char *regs_query_register_name(unsigned int offset)
806 const struct pt_regs_offset *roff;
807 for (roff = regoffset_table; roff->name != NULL; roff++)
808 if (roff->offset == offset)
814 * regs_within_kernel_stack() - check the address in the stack
815 * @regs: pt_regs which contains kernel stack pointer.
816 * @addr: address which is checked.
818 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
819 * If @addr is within the kernel stack, it returns true. If not, returns false.
821 int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
823 return ((addr & ~(THREAD_SIZE - 1)) ==
824 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
828 * regs_get_kernel_stack_nth() - get Nth entry of the stack
829 * @regs: pt_regs which contains kernel stack pointer.
830 * @n: stack entry number.
832 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
833 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
836 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
838 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
842 if (!regs_within_kernel_stack(regs, (unsigned long)addr))