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>
64 #define REGSET_GENERAL \
66 BUILD_BUG_ON((int)REGSET32_GENERAL != (int)REGSET64_GENERAL); \
72 BUILD_BUG_ON((int)REGSET32_FP != (int)REGSET64_FP); \
77 struct pt_regs_offset {
82 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
83 #define REG_OFFSET_END {.name = NULL, .offset = 0}
85 static const struct pt_regs_offset regoffset_table[] = {
109 REG_OFFSET_NAME(orig_ax),
112 REG_OFFSET_NAME(flags),
119 * regs_query_register_offset() - query register offset from its name
120 * @name: the name of a register
122 * regs_query_register_offset() returns the offset of a register in struct
123 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
125 int regs_query_register_offset(const char *name)
127 const struct pt_regs_offset *roff;
128 for (roff = regoffset_table; roff->name != NULL; roff++)
129 if (!strcmp(roff->name, name))
135 * regs_query_register_name() - query register name from its offset
136 * @offset: the offset of a register in struct pt_regs.
138 * regs_query_register_name() returns the name of a register from its
139 * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
141 const char *regs_query_register_name(unsigned int offset)
143 const struct pt_regs_offset *roff;
144 for (roff = regoffset_table; roff->name != NULL; roff++)
145 if (roff->offset == offset)
151 * does not yet catch signals sent when the child dies.
152 * in exit.c or in signal.c.
156 * Determines which flags the user has access to [1 = access, 0 = no access].
158 #define FLAG_MASK_32 ((unsigned long) \
159 (X86_EFLAGS_CF | X86_EFLAGS_PF | \
160 X86_EFLAGS_AF | X86_EFLAGS_ZF | \
161 X86_EFLAGS_SF | X86_EFLAGS_TF | \
162 X86_EFLAGS_DF | X86_EFLAGS_OF | \
163 X86_EFLAGS_RF | X86_EFLAGS_AC))
166 * Determines whether a value may be installed in a segment register.
168 static inline bool invalid_selector(u16 value)
170 return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
175 #define FLAG_MASK FLAG_MASK_32
177 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
179 BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
180 return ®s->bx + (regno >> 2);
183 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
186 * Returning the value truncates it to 16 bits.
189 if (offset != offsetof(struct user_regs_struct, gs))
190 retval = *pt_regs_access(task_pt_regs(task), offset);
193 savesegment(gs, retval);
195 retval = task->thread.gs;
200 static int set_segment_reg(struct task_struct *task,
201 unsigned long offset, u16 value)
203 if (WARN_ON_ONCE(task == current))
207 * The value argument was already truncated to 16 bits.
209 if (invalid_selector(value))
213 * For %cs and %ss we cannot permit a null selector.
214 * We can permit a bogus selector as long as it has USER_RPL.
215 * Null selectors are fine for other segment registers, but
216 * we will never get back to user mode with invalid %cs or %ss
217 * and will take the trap in iret instead. Much code relies
218 * on user_mode() to distinguish a user trap frame (which can
219 * safely use invalid selectors) from a kernel trap frame.
222 case offsetof(struct user_regs_struct, cs):
223 case offsetof(struct user_regs_struct, ss):
224 if (unlikely(value == 0))
229 *pt_regs_access(task_pt_regs(task), offset) = value;
232 case offsetof(struct user_regs_struct, gs):
233 task->thread.gs = value;
239 #else /* CONFIG_X86_64 */
241 #define FLAG_MASK (FLAG_MASK_32 | X86_EFLAGS_NT)
243 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
245 BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
246 return ®s->r15 + (offset / sizeof(regs->r15));
249 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
252 * Returning the value truncates it to 16 bits.
257 case offsetof(struct user_regs_struct, fs):
258 if (task == current) {
259 /* Older gas can't assemble movq %?s,%r?? */
260 asm("movl %%fs,%0" : "=r" (seg));
263 return task->thread.fsindex;
264 case offsetof(struct user_regs_struct, gs):
265 if (task == current) {
266 asm("movl %%gs,%0" : "=r" (seg));
269 return task->thread.gsindex;
270 case offsetof(struct user_regs_struct, ds):
271 if (task == current) {
272 asm("movl %%ds,%0" : "=r" (seg));
275 return task->thread.ds;
276 case offsetof(struct user_regs_struct, es):
277 if (task == current) {
278 asm("movl %%es,%0" : "=r" (seg));
281 return task->thread.es;
283 case offsetof(struct user_regs_struct, cs):
284 case offsetof(struct user_regs_struct, ss):
287 return *pt_regs_access(task_pt_regs(task), offset);
290 static int set_segment_reg(struct task_struct *task,
291 unsigned long offset, u16 value)
293 if (WARN_ON_ONCE(task == current))
297 * The value argument was already truncated to 16 bits.
299 if (invalid_selector(value))
303 * Writes to FS and GS will change the stored selector. Whether
304 * this changes the segment base as well depends on whether
305 * FSGSBASE is enabled.
309 case offsetof(struct user_regs_struct,fs):
310 task->thread.fsindex = value;
312 case offsetof(struct user_regs_struct,gs):
313 task->thread.gsindex = value;
315 case offsetof(struct user_regs_struct,ds):
316 task->thread.ds = value;
318 case offsetof(struct user_regs_struct,es):
319 task->thread.es = value;
323 * Can't actually change these in 64-bit mode.
325 case offsetof(struct user_regs_struct,cs):
326 if (unlikely(value == 0))
328 task_pt_regs(task)->cs = value;
330 case offsetof(struct user_regs_struct,ss):
331 if (unlikely(value == 0))
333 task_pt_regs(task)->ss = value;
340 #endif /* CONFIG_X86_32 */
342 static unsigned long get_flags(struct task_struct *task)
344 unsigned long retval = task_pt_regs(task)->flags;
347 * If the debugger set TF, hide it from the readout.
349 if (test_tsk_thread_flag(task, TIF_FORCED_TF))
350 retval &= ~X86_EFLAGS_TF;
355 static int set_flags(struct task_struct *task, unsigned long value)
357 struct pt_regs *regs = task_pt_regs(task);
360 * If the user value contains TF, mark that
361 * it was not "us" (the debugger) that set it.
362 * If not, make sure it stays set if we had.
364 if (value & X86_EFLAGS_TF)
365 clear_tsk_thread_flag(task, TIF_FORCED_TF);
366 else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
367 value |= X86_EFLAGS_TF;
369 regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
374 static int putreg(struct task_struct *child,
375 unsigned long offset, unsigned long value)
378 case offsetof(struct user_regs_struct, cs):
379 case offsetof(struct user_regs_struct, ds):
380 case offsetof(struct user_regs_struct, es):
381 case offsetof(struct user_regs_struct, fs):
382 case offsetof(struct user_regs_struct, gs):
383 case offsetof(struct user_regs_struct, ss):
384 return set_segment_reg(child, offset, value);
386 case offsetof(struct user_regs_struct, flags):
387 return set_flags(child, value);
390 case offsetof(struct user_regs_struct,fs_base):
391 if (value >= TASK_SIZE_MAX)
393 x86_fsbase_write_task(child, value);
395 case offsetof(struct user_regs_struct,gs_base):
396 if (value >= TASK_SIZE_MAX)
398 x86_gsbase_write_task(child, value);
403 *pt_regs_access(task_pt_regs(child), offset) = value;
407 static unsigned long getreg(struct task_struct *task, unsigned long offset)
410 case offsetof(struct user_regs_struct, cs):
411 case offsetof(struct user_regs_struct, ds):
412 case offsetof(struct user_regs_struct, es):
413 case offsetof(struct user_regs_struct, fs):
414 case offsetof(struct user_regs_struct, gs):
415 case offsetof(struct user_regs_struct, ss):
416 return get_segment_reg(task, offset);
418 case offsetof(struct user_regs_struct, flags):
419 return get_flags(task);
422 case offsetof(struct user_regs_struct, fs_base):
423 return x86_fsbase_read_task(task);
424 case offsetof(struct user_regs_struct, gs_base):
425 return x86_gsbase_read_task(task);
429 return *pt_regs_access(task_pt_regs(task), offset);
432 static int genregs_get(struct task_struct *target,
433 const struct user_regset *regset,
438 for (reg = 0; to.left; reg++)
439 membuf_store(&to, getreg(target, reg * sizeof(unsigned long)));
443 static int genregs_set(struct task_struct *target,
444 const struct user_regset *regset,
445 unsigned int pos, unsigned int count,
446 const void *kbuf, const void __user *ubuf)
450 const unsigned long *k = kbuf;
451 while (count >= sizeof(*k) && !ret) {
452 ret = putreg(target, pos, *k++);
457 const unsigned long __user *u = ubuf;
458 while (count >= sizeof(*u) && !ret) {
460 ret = __get_user(word, u++);
463 ret = putreg(target, pos, word);
471 static void ptrace_triggered(struct perf_event *bp,
472 struct perf_sample_data *data,
473 struct pt_regs *regs)
476 struct thread_struct *thread = &(current->thread);
479 * Store in the virtual DR6 register the fact that the breakpoint
480 * was hit so the thread's debugger will see it.
482 for (i = 0; i < HBP_NUM; i++) {
483 if (thread->ptrace_bps[i] == bp)
487 thread->virtual_dr6 |= (DR_TRAP0 << i);
491 * Walk through every ptrace breakpoints for this thread and
492 * build the dr7 value on top of their attributes.
495 static unsigned long ptrace_get_dr7(struct perf_event *bp[])
499 struct arch_hw_breakpoint *info;
501 for (i = 0; i < HBP_NUM; i++) {
502 if (bp[i] && !bp[i]->attr.disabled) {
503 info = counter_arch_bp(bp[i]);
504 dr7 |= encode_dr7(i, info->len, info->type);
511 static int ptrace_fill_bp_fields(struct perf_event_attr *attr,
512 int len, int type, bool disabled)
514 int err, bp_len, bp_type;
516 err = arch_bp_generic_fields(len, type, &bp_len, &bp_type);
518 attr->bp_len = bp_len;
519 attr->bp_type = bp_type;
520 attr->disabled = disabled;
526 static struct perf_event *
527 ptrace_register_breakpoint(struct task_struct *tsk, int len, int type,
528 unsigned long addr, bool disabled)
530 struct perf_event_attr attr;
533 ptrace_breakpoint_init(&attr);
536 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
540 return register_user_hw_breakpoint(&attr, ptrace_triggered,
544 static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
547 struct perf_event_attr attr = bp->attr;
550 err = ptrace_fill_bp_fields(&attr, len, type, disabled);
554 return modify_user_hw_breakpoint(bp, &attr);
558 * Handle ptrace writes to debug register 7.
560 static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
562 struct thread_struct *thread = &tsk->thread;
563 unsigned long old_dr7;
564 bool second_pass = false;
567 data &= ~DR_CONTROL_RESERVED;
568 old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
572 for (i = 0; i < HBP_NUM; i++) {
574 bool disabled = !decode_dr7(data, i, &len, &type);
575 struct perf_event *bp = thread->ptrace_bps[i];
581 bp = ptrace_register_breakpoint(tsk,
582 len, type, 0, disabled);
588 thread->ptrace_bps[i] = bp;
592 rc = ptrace_modify_breakpoint(bp, len, type, disabled);
597 /* Restore if the first pass failed, second_pass shouldn't fail. */
598 if (rc && !WARN_ON(second_pass)) {
609 * Handle PTRACE_PEEKUSR calls for the debug register area.
611 static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
613 struct thread_struct *thread = &tsk->thread;
614 unsigned long val = 0;
617 int index = array_index_nospec(n, HBP_NUM);
618 struct perf_event *bp = thread->ptrace_bps[index];
621 val = bp->hw.info.address;
623 val = thread->virtual_dr6 ^ DR6_RESERVED; /* Flip back to arch polarity */
625 val = thread->ptrace_dr7;
630 static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
633 struct thread_struct *t = &tsk->thread;
634 struct perf_event *bp = t->ptrace_bps[nr];
639 * Put stub len and type to create an inactive but correct bp.
641 * CHECKME: the previous code returned -EIO if the addr wasn't
642 * a valid task virtual addr. The new one will return -EINVAL in
644 * -EINVAL may be what we want for in-kernel breakpoints users,
645 * but -EIO looks better for ptrace, since we refuse a register
646 * writing for the user. And anyway this is the previous
649 bp = ptrace_register_breakpoint(tsk,
650 X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE,
655 t->ptrace_bps[nr] = bp;
657 struct perf_event_attr attr = bp->attr;
660 err = modify_user_hw_breakpoint(bp, &attr);
667 * Handle PTRACE_POKEUSR calls for the debug register area.
669 static int ptrace_set_debugreg(struct task_struct *tsk, int n,
672 struct thread_struct *thread = &tsk->thread;
673 /* There are no DR4 or DR5 registers */
677 rc = ptrace_set_breakpoint_addr(tsk, n, val);
679 thread->virtual_dr6 = val ^ DR6_RESERVED; /* Flip to positive polarity */
682 rc = ptrace_write_dr7(tsk, val);
684 thread->ptrace_dr7 = val;
690 * These access the current or another (stopped) task's io permission
691 * bitmap for debugging or core dump.
693 static int ioperm_active(struct task_struct *target,
694 const struct user_regset *regset)
696 struct io_bitmap *iobm = target->thread.io_bitmap;
698 return iobm ? DIV_ROUND_UP(iobm->max, regset->size) : 0;
701 static int ioperm_get(struct task_struct *target,
702 const struct user_regset *regset,
705 struct io_bitmap *iobm = target->thread.io_bitmap;
710 return membuf_write(&to, iobm->bitmap, IO_BITMAP_BYTES);
714 * Called by kernel/ptrace.c when detaching..
716 * Make sure the single step bit is not set.
718 void ptrace_disable(struct task_struct *child)
720 user_disable_single_step(child);
723 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
724 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
727 static const struct user_regset_view user_x86_64_view; /* Initialized below. */
730 long arch_ptrace(struct task_struct *child, long request,
731 unsigned long addr, unsigned long data)
734 unsigned long __user *datap = (unsigned long __user *)data;
737 /* This is native 64-bit ptrace() */
738 const struct user_regset_view *regset_view = &user_x86_64_view;
740 /* This is native 32-bit ptrace() */
741 const struct user_regset_view *regset_view = &user_x86_32_view;
745 /* read the word at location addr in the USER area. */
746 case PTRACE_PEEKUSR: {
750 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
753 tmp = 0; /* Default return condition */
754 if (addr < sizeof(struct user_regs_struct))
755 tmp = getreg(child, addr);
756 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
757 addr <= offsetof(struct user, u_debugreg[7])) {
758 addr -= offsetof(struct user, u_debugreg[0]);
759 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
761 ret = put_user(tmp, datap);
765 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
767 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
770 if (addr < sizeof(struct user_regs_struct))
771 ret = putreg(child, addr, data);
772 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
773 addr <= offsetof(struct user, u_debugreg[7])) {
774 addr -= offsetof(struct user, u_debugreg[0]);
775 ret = ptrace_set_debugreg(child,
776 addr / sizeof(data), data);
780 case PTRACE_GETREGS: /* Get all gp regs from the child. */
781 return copy_regset_to_user(child,
784 0, sizeof(struct user_regs_struct),
787 case PTRACE_SETREGS: /* Set all gp regs in the child. */
788 return copy_regset_from_user(child,
791 0, sizeof(struct user_regs_struct),
794 case PTRACE_GETFPREGS: /* Get the child FPU state. */
795 return copy_regset_to_user(child,
798 0, sizeof(struct user_i387_struct),
801 case PTRACE_SETFPREGS: /* Set the child FPU state. */
802 return copy_regset_from_user(child,
805 0, sizeof(struct user_i387_struct),
809 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
810 return copy_regset_to_user(child, &user_x86_32_view,
812 0, sizeof(struct user_fxsr_struct),
815 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
816 return copy_regset_from_user(child, &user_x86_32_view,
818 0, sizeof(struct user_fxsr_struct),
822 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
823 case PTRACE_GET_THREAD_AREA:
826 ret = do_get_thread_area(child, addr,
827 (struct user_desc __user *)data);
830 case PTRACE_SET_THREAD_AREA:
833 ret = do_set_thread_area(child, addr,
834 (struct user_desc __user *)data, 0);
839 /* normal 64bit interface to access TLS data.
840 Works just like arch_prctl, except that the arguments
842 case PTRACE_ARCH_PRCTL:
843 ret = do_arch_prctl_64(child, data, addr);
848 ret = ptrace_request(child, request, addr, data);
855 #ifdef CONFIG_IA32_EMULATION
857 #include <linux/compat.h>
858 #include <linux/syscalls.h>
859 #include <asm/ia32.h>
860 #include <asm/user32.h>
863 case offsetof(struct user32, regs.l): \
864 regs->q = value; break
867 case offsetof(struct user32, regs.rs): \
868 return set_segment_reg(child, \
869 offsetof(struct user_regs_struct, rs), \
873 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
875 struct pt_regs *regs = task_pt_regs(child);
885 * A 32-bit ptracer on a 64-bit kernel expects that writing
886 * FS or GS will also update the base. This is needed for
887 * operations like PTRACE_SETREGS to fully restore a saved
891 case offsetof(struct user32, regs.fs):
892 ret = set_segment_reg(child,
893 offsetof(struct user_regs_struct, fs),
896 child->thread.fsbase =
897 x86_fsgsbase_read_task(child, value);
900 case offsetof(struct user32, regs.gs):
901 ret = set_segment_reg(child,
902 offsetof(struct user_regs_struct, gs),
905 child->thread.gsbase =
906 x86_fsgsbase_read_task(child, value);
921 case offsetof(struct user32, regs.orig_eax):
923 * Warning: bizarre corner case fixup here. A 32-bit
924 * debugger setting orig_eax to -1 wants to disable
925 * syscall restart. Make sure that the syscall
926 * restart code sign-extends orig_ax. Also make sure
927 * we interpret the -ERESTART* codes correctly if
928 * loaded into regs->ax in case the task is not
929 * actually still sitting at the exit from a 32-bit
930 * syscall with TS_COMPAT still set.
932 regs->orig_ax = value;
933 if (syscall_get_nr(child, regs) != -1)
934 child->thread_info.status |= TS_I386_REGS_POKED;
937 case offsetof(struct user32, regs.eflags):
938 return set_flags(child, value);
940 case offsetof(struct user32, u_debugreg[0]) ...
941 offsetof(struct user32, u_debugreg[7]):
942 regno -= offsetof(struct user32, u_debugreg[0]);
943 return ptrace_set_debugreg(child, regno / 4, value);
946 if (regno > sizeof(struct user32) || (regno & 3))
950 * Other dummy fields in the virtual user structure
962 case offsetof(struct user32, regs.l): \
963 *val = regs->q; break
966 case offsetof(struct user32, regs.rs): \
967 *val = get_segment_reg(child, \
968 offsetof(struct user_regs_struct, rs)); \
971 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
973 struct pt_regs *regs = task_pt_regs(child);
991 R32(orig_eax, orig_ax);
995 case offsetof(struct user32, regs.eflags):
996 *val = get_flags(child);
999 case offsetof(struct user32, u_debugreg[0]) ...
1000 offsetof(struct user32, u_debugreg[7]):
1001 regno -= offsetof(struct user32, u_debugreg[0]);
1002 *val = ptrace_get_debugreg(child, regno / 4);
1006 if (regno > sizeof(struct user32) || (regno & 3))
1010 * Other dummy fields in the virtual user structure
1022 static int genregs32_get(struct task_struct *target,
1023 const struct user_regset *regset,
1028 for (reg = 0; to.left; reg++) {
1030 getreg32(target, reg * 4, &val);
1031 membuf_store(&to, val);
1036 static int genregs32_set(struct task_struct *target,
1037 const struct user_regset *regset,
1038 unsigned int pos, unsigned int count,
1039 const void *kbuf, const void __user *ubuf)
1043 const compat_ulong_t *k = kbuf;
1044 while (count >= sizeof(*k) && !ret) {
1045 ret = putreg32(target, pos, *k++);
1046 count -= sizeof(*k);
1050 const compat_ulong_t __user *u = ubuf;
1051 while (count >= sizeof(*u) && !ret) {
1052 compat_ulong_t word;
1053 ret = __get_user(word, u++);
1056 ret = putreg32(target, pos, word);
1057 count -= sizeof(*u);
1064 static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
1065 compat_ulong_t caddr, compat_ulong_t cdata)
1067 unsigned long addr = caddr;
1068 unsigned long data = cdata;
1069 void __user *datap = compat_ptr(data);
1074 case PTRACE_PEEKUSR:
1075 ret = getreg32(child, addr, &val);
1077 ret = put_user(val, (__u32 __user *)datap);
1080 case PTRACE_POKEUSR:
1081 ret = putreg32(child, addr, data);
1084 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1085 return copy_regset_to_user(child, &user_x86_32_view,
1087 0, sizeof(struct user_regs_struct32),
1090 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1091 return copy_regset_from_user(child, &user_x86_32_view,
1093 sizeof(struct user_regs_struct32),
1096 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1097 return copy_regset_to_user(child, &user_x86_32_view,
1099 sizeof(struct user_i387_ia32_struct),
1102 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1103 return copy_regset_from_user(
1104 child, &user_x86_32_view, REGSET_FP,
1105 0, sizeof(struct user_i387_ia32_struct), datap);
1107 case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1108 return copy_regset_to_user(child, &user_x86_32_view,
1110 sizeof(struct user32_fxsr_struct),
1113 case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1114 return copy_regset_from_user(child, &user_x86_32_view,
1116 sizeof(struct user32_fxsr_struct),
1119 case PTRACE_GET_THREAD_AREA:
1120 case PTRACE_SET_THREAD_AREA:
1121 return arch_ptrace(child, request, addr, data);
1124 return compat_ptrace_request(child, request, addr, data);
1129 #endif /* CONFIG_IA32_EMULATION */
1131 #ifdef CONFIG_X86_X32_ABI
1132 static long x32_arch_ptrace(struct task_struct *child,
1133 compat_long_t request, compat_ulong_t caddr,
1134 compat_ulong_t cdata)
1136 unsigned long addr = caddr;
1137 unsigned long data = cdata;
1138 void __user *datap = compat_ptr(data);
1142 /* Read 32bits at location addr in the USER area. Only allow
1143 to return the lower 32bits of segment and debug registers. */
1144 case PTRACE_PEEKUSR: {
1148 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1149 addr < offsetof(struct user_regs_struct, cs))
1152 tmp = 0; /* Default return condition */
1153 if (addr < sizeof(struct user_regs_struct))
1154 tmp = getreg(child, addr);
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 tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1160 ret = put_user(tmp, (__u32 __user *)datap);
1164 /* Write the word at location addr in the USER area. Only allow
1165 to update segment and debug registers with the upper 32bits
1167 case PTRACE_POKEUSR:
1169 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1170 addr < offsetof(struct user_regs_struct, cs))
1173 if (addr < sizeof(struct user_regs_struct))
1174 ret = putreg(child, addr, data);
1175 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1176 addr <= offsetof(struct user, u_debugreg[7])) {
1177 addr -= offsetof(struct user, u_debugreg[0]);
1178 ret = ptrace_set_debugreg(child,
1179 addr / sizeof(data), data);
1183 case PTRACE_GETREGS: /* Get all gp regs from the child. */
1184 return copy_regset_to_user(child,
1187 0, sizeof(struct user_regs_struct),
1190 case PTRACE_SETREGS: /* Set all gp regs in the child. */
1191 return copy_regset_from_user(child,
1194 0, sizeof(struct user_regs_struct),
1197 case PTRACE_GETFPREGS: /* Get the child FPU state. */
1198 return copy_regset_to_user(child,
1201 0, sizeof(struct user_i387_struct),
1204 case PTRACE_SETFPREGS: /* Set the child FPU state. */
1205 return copy_regset_from_user(child,
1208 0, sizeof(struct user_i387_struct),
1212 return compat_ptrace_request(child, request, addr, data);
1219 #ifdef CONFIG_COMPAT
1220 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1221 compat_ulong_t caddr, compat_ulong_t cdata)
1223 #ifdef CONFIG_X86_X32_ABI
1224 if (!in_ia32_syscall())
1225 return x32_arch_ptrace(child, request, caddr, cdata);
1227 #ifdef CONFIG_IA32_EMULATION
1228 return ia32_arch_ptrace(child, request, caddr, cdata);
1233 #endif /* CONFIG_COMPAT */
1235 #ifdef CONFIG_X86_64
1237 static struct user_regset x86_64_regsets[] __ro_after_init = {
1238 [REGSET64_GENERAL] = {
1239 .core_note_type = NT_PRSTATUS,
1240 .n = sizeof(struct user_regs_struct) / sizeof(long),
1241 .size = sizeof(long),
1242 .align = sizeof(long),
1243 .regset_get = genregs_get,
1247 .core_note_type = NT_PRFPREG,
1248 .n = sizeof(struct fxregs_state) / sizeof(long),
1249 .size = sizeof(long),
1250 .align = sizeof(long),
1251 .active = regset_xregset_fpregs_active,
1252 .regset_get = xfpregs_get,
1255 [REGSET64_XSTATE] = {
1256 .core_note_type = NT_X86_XSTATE,
1257 .size = sizeof(u64),
1258 .align = sizeof(u64),
1259 .active = xstateregs_active,
1260 .regset_get = xstateregs_get,
1261 .set = xstateregs_set
1263 [REGSET64_IOPERM] = {
1264 .core_note_type = NT_386_IOPERM,
1265 .n = IO_BITMAP_LONGS,
1266 .size = sizeof(long),
1267 .align = sizeof(long),
1268 .active = ioperm_active,
1269 .regset_get = ioperm_get
1271 #ifdef CONFIG_X86_USER_SHADOW_STACK
1273 .core_note_type = NT_X86_SHSTK,
1275 .size = sizeof(u64),
1276 .align = sizeof(u64),
1277 .active = ssp_active,
1278 .regset_get = ssp_get,
1284 static const struct user_regset_view user_x86_64_view = {
1285 .name = "x86_64", .e_machine = EM_X86_64,
1286 .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1289 #else /* CONFIG_X86_32 */
1291 #define user_regs_struct32 user_regs_struct
1292 #define genregs32_get genregs_get
1293 #define genregs32_set genregs_set
1295 #endif /* CONFIG_X86_64 */
1297 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1298 static struct user_regset x86_32_regsets[] __ro_after_init = {
1299 [REGSET32_GENERAL] = {
1300 .core_note_type = NT_PRSTATUS,
1301 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1302 .size = sizeof(u32),
1303 .align = sizeof(u32),
1304 .regset_get = genregs32_get,
1305 .set = genregs32_set
1308 .core_note_type = NT_PRFPREG,
1309 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1310 .size = sizeof(u32),
1311 .align = sizeof(u32),
1312 .active = regset_fpregs_active,
1313 .regset_get = fpregs_get,
1317 .core_note_type = NT_PRXFPREG,
1318 .n = sizeof(struct fxregs_state) / sizeof(u32),
1319 .size = sizeof(u32),
1320 .align = sizeof(u32),
1321 .active = regset_xregset_fpregs_active,
1322 .regset_get = xfpregs_get,
1325 [REGSET32_XSTATE] = {
1326 .core_note_type = NT_X86_XSTATE,
1327 .size = sizeof(u64),
1328 .align = sizeof(u64),
1329 .active = xstateregs_active,
1330 .regset_get = xstateregs_get,
1331 .set = xstateregs_set
1334 .core_note_type = NT_386_TLS,
1335 .n = GDT_ENTRY_TLS_ENTRIES,
1336 .bias = GDT_ENTRY_TLS_MIN,
1337 .size = sizeof(struct user_desc),
1338 .align = sizeof(struct user_desc),
1339 .active = regset_tls_active,
1340 .regset_get = regset_tls_get,
1341 .set = regset_tls_set
1343 [REGSET32_IOPERM] = {
1344 .core_note_type = NT_386_IOPERM,
1345 .n = IO_BITMAP_BYTES / sizeof(u32),
1346 .size = sizeof(u32),
1347 .align = sizeof(u32),
1348 .active = ioperm_active,
1349 .regset_get = ioperm_get
1353 static const struct user_regset_view user_x86_32_view = {
1354 .name = "i386", .e_machine = EM_386,
1355 .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1360 * This represents bytes 464..511 in the memory layout exported through
1361 * the REGSET_XSTATE interface.
1363 u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1365 void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1367 #ifdef CONFIG_X86_64
1368 x86_64_regsets[REGSET64_XSTATE].n = size / sizeof(u64);
1370 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1371 x86_32_regsets[REGSET32_XSTATE].n = size / sizeof(u64);
1373 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1377 * This is used by the core dump code to decide which regset to dump. The
1378 * core dump code writes out the resulting .e_machine and the corresponding
1379 * regsets. This is suboptimal if the task is messing around with its CS.L
1380 * field, but at worst the core dump will end up missing some information.
1382 * Unfortunately, it is also used by the broken PTRACE_GETREGSET and
1383 * PTRACE_SETREGSET APIs. These APIs look at the .regsets field but have
1384 * no way to make sure that the e_machine they use matches the caller's
1385 * expectations. The result is that the data format returned by
1386 * PTRACE_GETREGSET depends on the returned CS field (and even the offset
1387 * of the returned CS field depends on its value!) and the data format
1388 * accepted by PTRACE_SETREGSET is determined by the old CS value. The
1389 * upshot is that it is basically impossible to use these APIs correctly.
1391 * The best way to fix it in the long run would probably be to add new
1392 * improved ptrace() APIs to read and write registers reliably, possibly by
1393 * allowing userspace to select the ELF e_machine variant that they expect.
1395 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1397 #ifdef CONFIG_IA32_EMULATION
1398 if (!user_64bit_mode(task_pt_regs(task)))
1400 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1401 return &user_x86_32_view;
1403 #ifdef CONFIG_X86_64
1404 return &user_x86_64_view;
1408 void send_sigtrap(struct pt_regs *regs, int error_code, int si_code)
1410 struct task_struct *tsk = current;
1412 tsk->thread.trap_nr = X86_TRAP_DB;
1413 tsk->thread.error_code = error_code;
1415 /* Send us the fake SIGTRAP */
1416 force_sig_fault(SIGTRAP, si_code,
1417 user_mode(regs) ? (void __user *)regs->ip : NULL);
1420 void user_single_step_report(struct pt_regs *regs)
1422 send_sigtrap(regs, 0, TRAP_BRKPT);