1 // SPDX-License-Identifier: GPL-2.0-only
2 /* By Ross Biro 1/23/92 */
4 * Pentium III FXSR, SSE support
5 * Gareth Hughes <gareth@valinux.com>, May 2000
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 #include <linux/sched/task_stack.h>
12 #include <linux/smp.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/ptrace.h>
16 #include <linux/user.h>
17 #include <linux/elf.h>
18 #include <linux/security.h>
19 #include <linux/audit.h>
20 #include <linux/seccomp.h>
21 #include <linux/signal.h>
22 #include <linux/perf_event.h>
23 #include <linux/hw_breakpoint.h>
24 #include <linux/rcupdate.h>
25 #include <linux/export.h>
26 #include <linux/context_tracking.h>
27 #include <linux/nospec.h>
29 #include <linux/uaccess.h>
30 #include <asm/processor.h>
31 #include <asm/fpu/signal.h>
32 #include <asm/fpu/regset.h>
33 #include <asm/fpu/xstate.h>
34 #include <asm/debugreg.h>
37 #include <asm/prctl.h>
38 #include <asm/proto.h>
39 #include <asm/hw_breakpoint.h>
40 #include <asm/traps.h>
41 #include <asm/syscall.h>
42 #include <asm/fsgsbase.h>
43 #include <asm/io_bitmap.h>
51 REGSET_IOPERM64 = REGSET_XFP,
57 struct pt_regs_offset {
62 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
63 #define REG_OFFSET_END {.name = NULL, .offset = 0}
65 static const struct pt_regs_offset regoffset_table[] = {
89 REG_OFFSET_NAME(orig_ax),
92 REG_OFFSET_NAME(flags),
99 * regs_query_register_offset() - query register offset from its name
100 * @name: the name of a register
102 * regs_query_register_offset() returns the offset of a register in struct
103 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
105 int regs_query_register_offset(const char *name)
107 const struct pt_regs_offset *roff;
108 for (roff = regoffset_table; roff->name != NULL; roff++)
109 if (!strcmp(roff->name, name))
115 * regs_query_register_name() - query register name from its offset
116 * @offset: the offset of a register in struct pt_regs.
118 * regs_query_register_name() returns the name of a register from its
119 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
121 const char *regs_query_register_name(unsigned int offset)
123 const struct pt_regs_offset *roff;
124 for (roff = regoffset_table; roff->name != NULL; roff++)
125 if (roff->offset == offset)
131 * does not yet catch signals sent when the child dies.
132 * in exit.c or in signal.c.
136 * Determines which flags the user has access to [1 = access, 0 = no access].
138 #define FLAG_MASK_32 ((unsigned long) \
139 (X86_EFLAGS_CF | X86_EFLAGS_PF | \
140 X86_EFLAGS_AF | X86_EFLAGS_ZF | \
141 X86_EFLAGS_SF | X86_EFLAGS_TF | \
142 X86_EFLAGS_DF | X86_EFLAGS_OF | \
143 X86_EFLAGS_RF | X86_EFLAGS_AC))
146 * Determines whether a value may be installed in a segment register.
148 static inline bool invalid_selector(u16 value)
150 return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
155 #define FLAG_MASK FLAG_MASK_32
157 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
159 BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
160 return ®s->bx + (regno >> 2);
163 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
166 * Returning the value truncates it to 16 bits.
169 if (offset != offsetof(struct user_regs_struct, gs))
170 retval = *pt_regs_access(task_pt_regs(task), offset);
173 savesegment(gs, retval);
175 retval = task->thread.gs;
180 static int set_segment_reg(struct task_struct *task,
181 unsigned long offset, u16 value)
183 if (WARN_ON_ONCE(task == current))
187 * The value argument was already truncated to 16 bits.
189 if (invalid_selector(value))
193 * For %cs and %ss we cannot permit a null selector.
194 * We can permit a bogus selector as long as it has USER_RPL.
195 * Null selectors are fine for other segment registers, but
196 * we will never get back to user mode with invalid %cs or %ss
197 * and will take the trap in iret instead. Much code relies
198 * on user_mode() to distinguish a user trap frame (which can
199 * safely use invalid selectors) from a kernel trap frame.
202 case offsetof(struct user_regs_struct, cs):
203 case offsetof(struct user_regs_struct, ss):
204 if (unlikely(value == 0))
209 *pt_regs_access(task_pt_regs(task), offset) = value;
212 case offsetof(struct user_regs_struct, gs):
213 task->thread.gs = value;
219 #else /* CONFIG_X86_64 */
221 #define FLAG_MASK (FLAG_MASK_32 | X86_EFLAGS_NT)
223 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
225 BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
226 return ®s->r15 + (offset / sizeof(regs->r15));
229 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
232 * Returning the value truncates it to 16 bits.
237 case offsetof(struct user_regs_struct, fs):
238 if (task == current) {
239 /* Older gas can't assemble movq %?s,%r?? */
240 asm("movl %%fs,%0" : "=r" (seg));
243 return task->thread.fsindex;
244 case offsetof(struct user_regs_struct, gs):
245 if (task == current) {
246 asm("movl %%gs,%0" : "=r" (seg));
249 return task->thread.gsindex;
250 case offsetof(struct user_regs_struct, ds):
251 if (task == current) {
252 asm("movl %%ds,%0" : "=r" (seg));
255 return task->thread.ds;
256 case offsetof(struct user_regs_struct, es):
257 if (task == current) {
258 asm("movl %%es,%0" : "=r" (seg));
261 return task->thread.es;
263 case offsetof(struct user_regs_struct, cs):
264 case offsetof(struct user_regs_struct, ss):
267 return *pt_regs_access(task_pt_regs(task), offset);
270 static int set_segment_reg(struct task_struct *task,
271 unsigned long offset, u16 value)
273 if (WARN_ON_ONCE(task == current))
277 * The value argument was already truncated to 16 bits.
279 if (invalid_selector(value))
283 * Writes to FS and GS will change the stored selector. Whether
284 * this changes the segment base as well depends on whether
285 * FSGSBASE is enabled.
289 case offsetof(struct user_regs_struct,fs):
290 task->thread.fsindex = value;
292 case offsetof(struct user_regs_struct,gs):
293 task->thread.gsindex = value;
295 case offsetof(struct user_regs_struct,ds):
296 task->thread.ds = value;
298 case offsetof(struct user_regs_struct,es):
299 task->thread.es = value;
303 * Can't actually change these in 64-bit mode.
305 case offsetof(struct user_regs_struct,cs):
306 if (unlikely(value == 0))
308 task_pt_regs(task)->cs = value;
310 case offsetof(struct user_regs_struct,ss):
311 if (unlikely(value == 0))
313 task_pt_regs(task)->ss = value;
320 #endif /* CONFIG_X86_32 */
322 static unsigned long get_flags(struct task_struct *task)
324 unsigned long retval = task_pt_regs(task)->flags;
327 * If the debugger set TF, hide it from the readout.
329 if (test_tsk_thread_flag(task, TIF_FORCED_TF))
330 retval &= ~X86_EFLAGS_TF;
335 static int set_flags(struct task_struct *task, unsigned long value)
337 struct pt_regs *regs = task_pt_regs(task);
340 * If the user value contains TF, mark that
341 * it was not "us" (the debugger) that set it.
342 * If not, make sure it stays set if we had.
344 if (value & X86_EFLAGS_TF)
345 clear_tsk_thread_flag(task, TIF_FORCED_TF);
346 else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
347 value |= X86_EFLAGS_TF;
349 regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
354 static int putreg(struct task_struct *child,
355 unsigned long offset, unsigned long value)
358 case offsetof(struct user_regs_struct, cs):
359 case offsetof(struct user_regs_struct, ds):
360 case offsetof(struct user_regs_struct, es):
361 case offsetof(struct user_regs_struct, fs):
362 case offsetof(struct user_regs_struct, gs):
363 case offsetof(struct user_regs_struct, ss):
364 return set_segment_reg(child, offset, value);
366 case offsetof(struct user_regs_struct, flags):
367 return set_flags(child, value);
370 case offsetof(struct user_regs_struct,fs_base):
371 if (value >= TASK_SIZE_MAX)
373 x86_fsbase_write_task(child, value);
375 case offsetof(struct user_regs_struct,gs_base):
376 if (value >= TASK_SIZE_MAX)
378 x86_gsbase_write_task(child, value);
383 *pt_regs_access(task_pt_regs(child), offset) = value;
387 static unsigned long getreg(struct task_struct *task, unsigned long offset)
390 case offsetof(struct user_regs_struct, cs):
391 case offsetof(struct user_regs_struct, ds):
392 case offsetof(struct user_regs_struct, es):
393 case offsetof(struct user_regs_struct, fs):
394 case offsetof(struct user_regs_struct, gs):
395 case offsetof(struct user_regs_struct, ss):
396 return get_segment_reg(task, offset);
398 case offsetof(struct user_regs_struct, flags):
399 return get_flags(task);
402 case offsetof(struct user_regs_struct, fs_base):
403 return x86_fsbase_read_task(task);
404 case offsetof(struct user_regs_struct, gs_base):
405 return x86_gsbase_read_task(task);
409 return *pt_regs_access(task_pt_regs(task), offset);
412 static int genregs_get(struct task_struct *target,
413 const struct user_regset *regset,
418 for (reg = 0; to.left; reg++)
419 membuf_store(&to, getreg(target, reg * sizeof(unsigned long)));
423 static int genregs_set(struct task_struct *target,
424 const struct user_regset *regset,
425 unsigned int pos, unsigned int count,
426 const void *kbuf, const void __user *ubuf)
430 const unsigned long *k = kbuf;
431 while (count >= sizeof(*k) && !ret) {
432 ret = putreg(target, pos, *k++);
437 const unsigned long __user *u = ubuf;
438 while (count >= sizeof(*u) && !ret) {
440 ret = __get_user(word, u++);
443 ret = putreg(target, pos, word);
451 static void ptrace_triggered(struct perf_event *bp,
452 struct perf_sample_data *data,
453 struct pt_regs *regs)
456 struct thread_struct *thread = &(current->thread);
459 * Store in the virtual DR6 register the fact that the breakpoint
460 * was hit so the thread's debugger will see it.
462 for (i = 0; i < HBP_NUM; i++) {
463 if (thread->ptrace_bps[i] == bp)
467 thread->virtual_dr6 |= (DR_TRAP0 << i);
471 * Walk through every ptrace breakpoints for this thread and
472 * build the dr7 value on top of their attributes.
475 static unsigned long ptrace_get_dr7(struct perf_event *bp[])
479 struct arch_hw_breakpoint *info;
481 for (i = 0; i < HBP_NUM; i++) {
482 if (bp[i] && !bp[i]->attr.disabled) {
483 info = counter_arch_bp(bp[i]);
484 dr7 |= encode_dr7(i, info->len, info->type);
491 static int ptrace_fill_bp_fields(struct perf_event_attr *attr,
492 int len, int type, bool disabled)
494 int err, bp_len, bp_type;
496 err = arch_bp_generic_fields(len, type, &bp_len, &bp_type);
498 attr->bp_len = bp_len;
499 attr->bp_type = bp_type;
500 attr->disabled = disabled;
506 static struct perf_event *
507 ptrace_register_breakpoint(struct task_struct *tsk, int len, int type,
508 unsigned long addr, bool disabled)
510 struct perf_event_attr attr;
513 ptrace_breakpoint_init(&attr);
516 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
520 return register_user_hw_breakpoint(&attr, ptrace_triggered,
524 static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
527 struct perf_event_attr attr = bp->attr;
530 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
534 return modify_user_hw_breakpoint(bp, &attr);
538 * Handle ptrace writes to debug register 7.
540 static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
542 struct thread_struct *thread = &tsk->thread;
543 unsigned long old_dr7;
544 bool second_pass = false;
547 data &= ~DR_CONTROL_RESERVED;
548 old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
552 for (i = 0; i < HBP_NUM; i++) {
554 bool disabled = !decode_dr7(data, i, &len, &type);
555 struct perf_event *bp = thread->ptrace_bps[i];
561 bp = ptrace_register_breakpoint(tsk,
562 len, type, 0, disabled);
568 thread->ptrace_bps[i] = bp;
572 rc = ptrace_modify_breakpoint(bp, len, type, disabled);
577 /* Restore if the first pass failed, second_pass shouldn't fail. */
578 if (rc && !WARN_ON(second_pass)) {
589 * Handle PTRACE_PEEKUSR calls for the debug register area.
591 static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
593 struct thread_struct *thread = &tsk->thread;
594 unsigned long val = 0;
597 int index = array_index_nospec(n, HBP_NUM);
598 struct perf_event *bp = thread->ptrace_bps[index];
601 val = bp->hw.info.address;
603 val = thread->virtual_dr6 ^ DR6_RESERVED; /* Flip back to arch polarity */
605 val = thread->ptrace_dr7;
610 static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
613 struct thread_struct *t = &tsk->thread;
614 struct perf_event *bp = t->ptrace_bps[nr];
619 * Put stub len and type to create an inactive but correct bp.
621 * CHECKME: the previous code returned -EIO if the addr wasn't
622 * a valid task virtual addr. The new one will return -EINVAL in
624 * -EINVAL may be what we want for in-kernel breakpoints users,
625 * but -EIO looks better for ptrace, since we refuse a register
626 * writing for the user. And anyway this is the previous
629 bp = ptrace_register_breakpoint(tsk,
630 X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE,
635 t->ptrace_bps[nr] = bp;
637 struct perf_event_attr attr = bp->attr;
640 err = modify_user_hw_breakpoint(bp, &attr);
647 * Handle PTRACE_POKEUSR calls for the debug register area.
649 static int ptrace_set_debugreg(struct task_struct *tsk, int n,
652 struct thread_struct *thread = &tsk->thread;
653 /* There are no DR4 or DR5 registers */
657 rc = ptrace_set_breakpoint_addr(tsk, n, val);
659 thread->virtual_dr6 = val ^ DR6_RESERVED; /* Flip to positive polarity */
662 rc = ptrace_write_dr7(tsk, val);
664 thread->ptrace_dr7 = val;
670 * These access the current or another (stopped) task's io permission
671 * bitmap for debugging or core dump.
673 static int ioperm_active(struct task_struct *target,
674 const struct user_regset *regset)
676 struct io_bitmap *iobm = target->thread.io_bitmap;
678 return iobm ? DIV_ROUND_UP(iobm->max, regset->size) : 0;
681 static int ioperm_get(struct task_struct *target,
682 const struct user_regset *regset,
685 struct io_bitmap *iobm = target->thread.io_bitmap;
690 return membuf_write(&to, iobm->bitmap, IO_BITMAP_BYTES);
694 * Called by kernel/ptrace.c when detaching..
696 * Make sure the single step bit is not set.
698 void ptrace_disable(struct task_struct *child)
700 user_disable_single_step(child);
703 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
704 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
707 static const struct user_regset_view user_x86_64_view; /* Initialized below. */
710 long arch_ptrace(struct task_struct *child, long request,
711 unsigned long addr, unsigned long data)
714 unsigned long __user *datap = (unsigned long __user *)data;
717 /* This is native 64-bit ptrace() */
718 const struct user_regset_view *regset_view = &user_x86_64_view;
720 /* This is native 32-bit ptrace() */
721 const struct user_regset_view *regset_view = &user_x86_32_view;
725 /* read the word at location addr in the USER area. */
726 case PTRACE_PEEKUSR: {
730 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
733 tmp = 0; /* Default return condition */
734 if (addr < sizeof(struct user_regs_struct))
735 tmp = getreg(child, addr);
736 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
737 addr <= offsetof(struct user, u_debugreg[7])) {
738 addr -= offsetof(struct user, u_debugreg[0]);
739 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
741 ret = put_user(tmp, datap);
745 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
747 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
750 if (addr < sizeof(struct user_regs_struct))
751 ret = putreg(child, addr, data);
752 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
753 addr <= offsetof(struct user, u_debugreg[7])) {
754 addr -= offsetof(struct user, u_debugreg[0]);
755 ret = ptrace_set_debugreg(child,
756 addr / sizeof(data), data);
760 case PTRACE_GETREGS: /* Get all gp regs from the child. */
761 return copy_regset_to_user(child,
764 0, sizeof(struct user_regs_struct),
767 case PTRACE_SETREGS: /* Set all gp regs in the child. */
768 return copy_regset_from_user(child,
771 0, sizeof(struct user_regs_struct),
774 case PTRACE_GETFPREGS: /* Get the child FPU state. */
775 return copy_regset_to_user(child,
778 0, sizeof(struct user_i387_struct),
781 case PTRACE_SETFPREGS: /* Set the child FPU state. */
782 return copy_regset_from_user(child,
785 0, sizeof(struct user_i387_struct),
789 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
790 return copy_regset_to_user(child, &user_x86_32_view,
792 0, sizeof(struct user_fxsr_struct),
795 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
796 return copy_regset_from_user(child, &user_x86_32_view,
798 0, sizeof(struct user_fxsr_struct),
802 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
803 case PTRACE_GET_THREAD_AREA:
806 ret = do_get_thread_area(child, addr,
807 (struct user_desc __user *)data);
810 case PTRACE_SET_THREAD_AREA:
813 ret = do_set_thread_area(child, addr,
814 (struct user_desc __user *)data, 0);
819 /* normal 64bit interface to access TLS data.
820 Works just like arch_prctl, except that the arguments
822 case PTRACE_ARCH_PRCTL:
823 ret = do_arch_prctl_64(child, data, addr);
828 ret = ptrace_request(child, request, addr, data);
835 #ifdef CONFIG_IA32_EMULATION
837 #include <linux/compat.h>
838 #include <linux/syscalls.h>
839 #include <asm/ia32.h>
840 #include <asm/user32.h>
843 case offsetof(struct user32, regs.l): \
844 regs->q = value; break
847 case offsetof(struct user32, regs.rs): \
848 return set_segment_reg(child, \
849 offsetof(struct user_regs_struct, rs), \
853 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
855 struct pt_regs *regs = task_pt_regs(child);
865 * A 32-bit ptracer on a 64-bit kernel expects that writing
866 * FS or GS will also update the base. This is needed for
867 * operations like PTRACE_SETREGS to fully restore a saved
871 case offsetof(struct user32, regs.fs):
872 ret = set_segment_reg(child,
873 offsetof(struct user_regs_struct, fs),
876 child->thread.fsbase =
877 x86_fsgsbase_read_task(child, value);
880 case offsetof(struct user32, regs.gs):
881 ret = set_segment_reg(child,
882 offsetof(struct user_regs_struct, gs),
885 child->thread.gsbase =
886 x86_fsgsbase_read_task(child, value);
901 case offsetof(struct user32, regs.orig_eax):
903 * Warning: bizarre corner case fixup here. A 32-bit
904 * debugger setting orig_eax to -1 wants to disable
905 * syscall restart. Make sure that the syscall
906 * restart code sign-extends orig_ax. Also make sure
907 * we interpret the -ERESTART* codes correctly if
908 * loaded into regs->ax in case the task is not
909 * actually still sitting at the exit from a 32-bit
910 * syscall with TS_COMPAT still set.
912 regs->orig_ax = value;
913 if (syscall_get_nr(child, regs) != -1)
914 child->thread_info.status |= TS_I386_REGS_POKED;
917 case offsetof(struct user32, regs.eflags):
918 return set_flags(child, value);
920 case offsetof(struct user32, u_debugreg[0]) ...
921 offsetof(struct user32, u_debugreg[7]):
922 regno -= offsetof(struct user32, u_debugreg[0]);
923 return ptrace_set_debugreg(child, regno / 4, value);
926 if (regno > sizeof(struct user32) || (regno & 3))
930 * Other dummy fields in the virtual user structure
942 case offsetof(struct user32, regs.l): \
943 *val = regs->q; break
946 case offsetof(struct user32, regs.rs): \
947 *val = get_segment_reg(child, \
948 offsetof(struct user_regs_struct, rs)); \
951 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
953 struct pt_regs *regs = task_pt_regs(child);
971 R32(orig_eax, orig_ax);
975 case offsetof(struct user32, regs.eflags):
976 *val = get_flags(child);
979 case offsetof(struct user32, u_debugreg[0]) ...
980 offsetof(struct user32, u_debugreg[7]):
981 regno -= offsetof(struct user32, u_debugreg[0]);
982 *val = ptrace_get_debugreg(child, regno / 4);
986 if (regno > sizeof(struct user32) || (regno & 3))
990 * Other dummy fields in the virtual user structure
1002 static int genregs32_get(struct task_struct *target,
1003 const struct user_regset *regset,
1008 for (reg = 0; to.left; reg++) {
1010 getreg32(target, reg * 4, &val);
1011 membuf_store(&to, val);
1016 static int genregs32_set(struct task_struct *target,
1017 const struct user_regset *regset,
1018 unsigned int pos, unsigned int count,
1019 const void *kbuf, const void __user *ubuf)
1023 const compat_ulong_t *k = kbuf;
1024 while (count >= sizeof(*k) && !ret) {
1025 ret = putreg32(target, pos, *k++);
1026 count -= sizeof(*k);
1030 const compat_ulong_t __user *u = ubuf;
1031 while (count >= sizeof(*u) && !ret) {
1032 compat_ulong_t word;
1033 ret = __get_user(word, u++);
1036 ret = putreg32(target, pos, word);
1037 count -= sizeof(*u);
1044 static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
1045 compat_ulong_t caddr, compat_ulong_t cdata)
1047 unsigned long addr = caddr;
1048 unsigned long data = cdata;
1049 void __user *datap = compat_ptr(data);
1054 case PTRACE_PEEKUSR:
1055 ret = getreg32(child, addr, &val);
1057 ret = put_user(val, (__u32 __user *)datap);
1060 case PTRACE_POKEUSR:
1061 ret = putreg32(child, addr, data);
1064 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1065 return copy_regset_to_user(child, &user_x86_32_view,
1067 0, sizeof(struct user_regs_struct32),
1070 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1071 return copy_regset_from_user(child, &user_x86_32_view,
1073 sizeof(struct user_regs_struct32),
1076 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1077 return copy_regset_to_user(child, &user_x86_32_view,
1079 sizeof(struct user_i387_ia32_struct),
1082 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1083 return copy_regset_from_user(
1084 child, &user_x86_32_view, REGSET_FP,
1085 0, sizeof(struct user_i387_ia32_struct), datap);
1087 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1088 return copy_regset_to_user(child, &user_x86_32_view,
1090 sizeof(struct user32_fxsr_struct),
1093 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1094 return copy_regset_from_user(child, &user_x86_32_view,
1096 sizeof(struct user32_fxsr_struct),
1099 case PTRACE_GET_THREAD_AREA:
1100 case PTRACE_SET_THREAD_AREA:
1101 return arch_ptrace(child, request, addr, data);
1104 return compat_ptrace_request(child, request, addr, data);
1109 #endif /* CONFIG_IA32_EMULATION */
1111 #ifdef CONFIG_X86_X32_ABI
1112 static long x32_arch_ptrace(struct task_struct *child,
1113 compat_long_t request, compat_ulong_t caddr,
1114 compat_ulong_t cdata)
1116 unsigned long addr = caddr;
1117 unsigned long data = cdata;
1118 void __user *datap = compat_ptr(data);
1122 /* Read 32bits at location addr in the USER area. Only allow
1123 to return the lower 32bits of segment and debug registers. */
1124 case PTRACE_PEEKUSR: {
1128 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1129 addr < offsetof(struct user_regs_struct, cs))
1132 tmp = 0; /* Default return condition */
1133 if (addr < sizeof(struct user_regs_struct))
1134 tmp = getreg(child, addr);
1135 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1136 addr <= offsetof(struct user, u_debugreg[7])) {
1137 addr -= offsetof(struct user, u_debugreg[0]);
1138 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1140 ret = put_user(tmp, (__u32 __user *)datap);
1144 /* Write the word at location addr in the USER area. Only allow
1145 to update segment and debug registers with the upper 32bits
1147 case PTRACE_POKEUSR:
1149 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1150 addr < offsetof(struct user_regs_struct, cs))
1153 if (addr < sizeof(struct user_regs_struct))
1154 ret = putreg(child, addr, data);
1155 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1156 addr <= offsetof(struct user, u_debugreg[7])) {
1157 addr -= offsetof(struct user, u_debugreg[0]);
1158 ret = ptrace_set_debugreg(child,
1159 addr / sizeof(data), data);
1163 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1164 return copy_regset_to_user(child,
1167 0, sizeof(struct user_regs_struct),
1170 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1171 return copy_regset_from_user(child,
1174 0, sizeof(struct user_regs_struct),
1177 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1178 return copy_regset_to_user(child,
1181 0, sizeof(struct user_i387_struct),
1184 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1185 return copy_regset_from_user(child,
1188 0, sizeof(struct user_i387_struct),
1192 return compat_ptrace_request(child, request, addr, data);
1199 #ifdef CONFIG_COMPAT
1200 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1201 compat_ulong_t caddr, compat_ulong_t cdata)
1203 #ifdef CONFIG_X86_X32_ABI
1204 if (!in_ia32_syscall())
1205 return x32_arch_ptrace(child, request, caddr, cdata);
1207 #ifdef CONFIG_IA32_EMULATION
1208 return ia32_arch_ptrace(child, request, caddr, cdata);
1213 #endif /* CONFIG_COMPAT */
1215 #ifdef CONFIG_X86_64
1217 static struct user_regset x86_64_regsets[] __ro_after_init = {
1218 [REGSET_GENERAL] = {
1219 .core_note_type = NT_PRSTATUS,
1220 .n = sizeof(struct user_regs_struct) / sizeof(long),
1221 .size = sizeof(long), .align = sizeof(long),
1222 .regset_get = genregs_get, .set = genregs_set
1225 .core_note_type = NT_PRFPREG,
1226 .n = sizeof(struct fxregs_state) / sizeof(long),
1227 .size = sizeof(long), .align = sizeof(long),
1228 .active = regset_xregset_fpregs_active, .regset_get = xfpregs_get, .set = xfpregs_set
1231 .core_note_type = NT_X86_XSTATE,
1232 .size = sizeof(u64), .align = sizeof(u64),
1233 .active = xstateregs_active, .regset_get = xstateregs_get,
1234 .set = xstateregs_set
1236 [REGSET_IOPERM64] = {
1237 .core_note_type = NT_386_IOPERM,
1238 .n = IO_BITMAP_LONGS,
1239 .size = sizeof(long), .align = sizeof(long),
1240 .active = ioperm_active, .regset_get = ioperm_get
1244 static const struct user_regset_view user_x86_64_view = {
1245 .name = "x86_64", .e_machine = EM_X86_64,
1246 .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1249 #else /* CONFIG_X86_32 */
1251 #define user_regs_struct32 user_regs_struct
1252 #define genregs32_get genregs_get
1253 #define genregs32_set genregs_set
1255 #endif /* CONFIG_X86_64 */
1257 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1258 static struct user_regset x86_32_regsets[] __ro_after_init = {
1259 [REGSET_GENERAL] = {
1260 .core_note_type = NT_PRSTATUS,
1261 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1262 .size = sizeof(u32), .align = sizeof(u32),
1263 .regset_get = genregs32_get, .set = genregs32_set
1266 .core_note_type = NT_PRFPREG,
1267 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1268 .size = sizeof(u32), .align = sizeof(u32),
1269 .active = regset_fpregs_active, .regset_get = fpregs_get, .set = fpregs_set
1272 .core_note_type = NT_PRXFPREG,
1273 .n = sizeof(struct fxregs_state) / sizeof(u32),
1274 .size = sizeof(u32), .align = sizeof(u32),
1275 .active = regset_xregset_fpregs_active, .regset_get = xfpregs_get, .set = xfpregs_set
1278 .core_note_type = NT_X86_XSTATE,
1279 .size = sizeof(u64), .align = sizeof(u64),
1280 .active = xstateregs_active, .regset_get = xstateregs_get,
1281 .set = xstateregs_set
1284 .core_note_type = NT_386_TLS,
1285 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1286 .size = sizeof(struct user_desc),
1287 .align = sizeof(struct user_desc),
1288 .active = regset_tls_active,
1289 .regset_get = regset_tls_get, .set = regset_tls_set
1291 [REGSET_IOPERM32] = {
1292 .core_note_type = NT_386_IOPERM,
1293 .n = IO_BITMAP_BYTES / sizeof(u32),
1294 .size = sizeof(u32), .align = sizeof(u32),
1295 .active = ioperm_active, .regset_get = ioperm_get
1299 static const struct user_regset_view user_x86_32_view = {
1300 .name = "i386", .e_machine = EM_386,
1301 .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1306 * This represents bytes 464..511 in the memory layout exported through
1307 * the REGSET_XSTATE interface.
1309 u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1311 void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1313 #ifdef CONFIG_X86_64
1314 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1316 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1317 x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1319 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1323 * This is used by the core dump code to decide which regset to dump. The
1324 * core dump code writes out the resulting .e_machine and the corresponding
1325 * regsets. This is suboptimal if the task is messing around with its CS.L
1326 * field, but at worst the core dump will end up missing some information.
1328 * Unfortunately, it is also used by the broken PTRACE_GETREGSET and
1329 * PTRACE_SETREGSET APIs. These APIs look at the .regsets field but have
1330 * no way to make sure that the e_machine they use matches the caller's
1331 * expectations. The result is that the data format returned by
1332 * PTRACE_GETREGSET depends on the returned CS field (and even the offset
1333 * of the returned CS field depends on its value!) and the data format
1334 * accepted by PTRACE_SETREGSET is determined by the old CS value. The
1335 * upshot is that it is basically impossible to use these APIs correctly.
1337 * The best way to fix it in the long run would probably be to add new
1338 * improved ptrace() APIs to read and write registers reliably, possibly by
1339 * allowing userspace to select the ELF e_machine variant that they expect.
1341 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1343 #ifdef CONFIG_IA32_EMULATION
1344 if (!user_64bit_mode(task_pt_regs(task)))
1346 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1347 return &user_x86_32_view;
1349 #ifdef CONFIG_X86_64
1350 return &user_x86_64_view;
1354 void send_sigtrap(struct pt_regs *regs, int error_code, int si_code)
1356 struct task_struct *tsk = current;
1358 tsk->thread.trap_nr = X86_TRAP_DB;
1359 tsk->thread.error_code = error_code;
1361 /* Send us the fake SIGTRAP */
1362 force_sig_fault(SIGTRAP, si_code,
1363 user_mode(regs) ? (void __user *)regs->ip : NULL);
1366 void user_single_step_report(struct pt_regs *regs)
1368 send_sigtrap(regs, 0, TRAP_BRKPT);