1 // SPDX-License-Identifier: GPL-2.0-only
111 	REG_OFFSET_NAME(cs),
119  * regs_query_register_offset() - query register offset from its name
123  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
128 	for (roff = regoffset_table; roff->name != NULL; roff++)  in regs_query_register_offset()
129 		if (!strcmp(roff->name, name))  in regs_query_register_offset()
130 			return roff->offset;  in regs_query_register_offset()
131 	return -EINVAL;  in regs_query_register_offset()
135  * regs_query_register_name() - query register name from its offset
144 	for (roff = regoffset_table; roff->name != NULL; roff++)  in regs_query_register_name()
145 		if (roff->offset == offset)  in regs_query_register_name()
146 			return roff->name;  in regs_query_register_name()
166  * Determines whether a value may be installed in a segment register.
168 static inline bool invalid_selector(u16 value)  in invalid_selector()  argument
170 	return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);  in invalid_selector()
180 	return &regs->bx + (regno >> 2);  in pt_regs_access()
186 	 * Returning the value truncates it to 16 bits.  in get_segment_reg()
195 			retval = task->thread.gs;  in get_segment_reg()
201 			   unsigned long offset, u16 value)  in set_segment_reg()  argument
204 		return -EIO;  in set_segment_reg()
207 	 * The value argument was already truncated to 16 bits.  in set_segment_reg()
209 	if (invalid_selector(value))  in set_segment_reg()
210 		return -EIO;  in set_segment_reg()
213 	 * For %cs and %ss we cannot permit a null selector.  in set_segment_reg()
216 	 * we will never get back to user mode with invalid %cs or %ss  in set_segment_reg()
222 	case offsetof(struct user_regs_struct, cs):  in set_segment_reg()
224 		if (unlikely(value == 0))  in set_segment_reg()
225 			return -EIO;  in set_segment_reg()
229 		*pt_regs_access(task_pt_regs(task), offset) = value;  in set_segment_reg()
233 		task->thread.gs = value;  in set_segment_reg()
246 	return &regs->r15 + (offset / sizeof(regs->r15));  in pt_regs_access()
252 	 * Returning the value truncates it to 16 bits.  in get_segment_reg()
263 		return task->thread.fsindex;  in get_segment_reg()
269 		return task->thread.gsindex;  in get_segment_reg()
275 		return task->thread.ds;  in get_segment_reg()
281 		return task->thread.es;  in get_segment_reg()
283 	case offsetof(struct user_regs_struct, cs):  in get_segment_reg()
291 			   unsigned long offset, u16 value)  in set_segment_reg()  argument
294 		return -EIO;  in set_segment_reg()
297 	 * The value argument was already truncated to 16 bits.  in set_segment_reg()
299 	if (invalid_selector(value))  in set_segment_reg()
300 		return -EIO;  in set_segment_reg()
310 		task->thread.fsindex = value;  in set_segment_reg()
313 		task->thread.gsindex = value;  in set_segment_reg()
316 		task->thread.ds = value;  in set_segment_reg()
319 		task->thread.es = value;  in set_segment_reg()
323 		 * Can't actually change these in 64-bit mode.  in set_segment_reg()
325 	case offsetof(struct user_regs_struct,cs):  in set_segment_reg()
326 		if (unlikely(value == 0))  in set_segment_reg()
327 			return -EIO;  in set_segment_reg()
328 		task_pt_regs(task)->cs = value;  in set_segment_reg()
331 		if (unlikely(value == 0))  in set_segment_reg()
332 			return -EIO;  in set_segment_reg()
333 		task_pt_regs(task)->ss = value;  in set_segment_reg()
344 	unsigned long retval = task_pt_regs(task)->flags;  in get_flags()
355 static int set_flags(struct task_struct *task, unsigned long value)  in set_flags()  argument
360 	 * If the user value contains TF, mark that  in set_flags()
364 	if (value & X86_EFLAGS_TF)  in set_flags()
367 		value |= X86_EFLAGS_TF;  in set_flags()
369 	regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);  in set_flags()
375 		  unsigned long offset, unsigned long value)  in putreg()  argument
378 	case offsetof(struct user_regs_struct, cs):  in putreg()
384 		return set_segment_reg(child, offset, value);  in putreg()
387 		return set_flags(child, value);  in putreg()
391 		if (value >= TASK_SIZE_MAX)  in putreg()
392 			return -EIO;  in putreg()
393 		x86_fsbase_write_task(child, value);  in putreg()
396 		if (value >= TASK_SIZE_MAX)  in putreg()
397 			return -EIO;  in putreg()
398 		x86_gsbase_write_task(child, value);  in putreg()
403 	*pt_regs_access(task_pt_regs(child), offset) = value;  in putreg()
410 	case offsetof(struct user_regs_struct, cs):  in getreg()
453 			count -= sizeof(*k);  in genregs_set()
464 			count -= sizeof(*u);  in genregs_set()
476 	struct thread_struct *thread = &(current->thread);  in ptrace_triggered()
483 		if (thread->ptrace_bps[i] == bp)  in ptrace_triggered()
487 	thread->virtual_dr6 |= (DR_TRAP0 << i);  in ptrace_triggered()
492  * build the dr7 value on top of their attributes.
502 		if (bp[i] && !bp[i]->attr.disabled) {  in ptrace_get_dr7()
504 			dr7 |= encode_dr7(i, info->len, info->type);  in ptrace_get_dr7()
518 		attr->bp_len = bp_len;  in ptrace_fill_bp_fields()
519 		attr->bp_type = bp_type;  in ptrace_fill_bp_fields()
520 		attr->disabled = disabled;  in ptrace_fill_bp_fields()
547 	struct perf_event_attr attr = bp->attr;  in ptrace_modify_breakpoint()
562 	struct thread_struct *thread = &tsk->thread;  in ptrace_write_dr7()
568 	old_dr7 = ptrace_get_dr7(thread->ptrace_bps);  in ptrace_write_dr7()
575 		struct perf_event *bp = thread->ptrace_bps[i];  in ptrace_write_dr7()
588 			thread->ptrace_bps[i] = bp;  in ptrace_write_dr7()
613 	struct thread_struct *thread = &tsk->thread;  in ptrace_get_debugreg()
618 		struct perf_event *bp = thread->ptrace_bps[index];  in ptrace_get_debugreg()
621 			val = bp->hw.info.address;  in ptrace_get_debugreg()
623 		val = thread->virtual_dr6 ^ DR6_RESERVED; /* Flip back to arch polarity */  in ptrace_get_debugreg()
625 		val = thread->ptrace_dr7;  in ptrace_get_debugreg()
633 	struct thread_struct *t = &tsk->thread;  in ptrace_set_breakpoint_addr()
634 	struct perf_event *bp = t->ptrace_bps[nr];  in ptrace_set_breakpoint_addr()
641 		 * CHECKME: the previous code returned -EIO if the addr wasn't  in ptrace_set_breakpoint_addr()
642 		 * a valid task virtual addr. The new one will return -EINVAL in  in ptrace_set_breakpoint_addr()
644 		 * -EINVAL may be what we want for in-kernel breakpoints users,  in ptrace_set_breakpoint_addr()
645 		 * but -EIO looks better for ptrace, since we refuse a register  in ptrace_set_breakpoint_addr()
655 			t->ptrace_bps[nr] = bp;  in ptrace_set_breakpoint_addr()
657 		struct perf_event_attr attr = bp->attr;  in ptrace_set_breakpoint_addr()
672 	struct thread_struct *thread = &tsk->thread;  in ptrace_set_debugreg()
674 	int rc = -EIO;  in ptrace_set_debugreg()
679 		thread->virtual_dr6 = val ^ DR6_RESERVED; /* Flip to positive polarity */  in ptrace_set_debugreg()
684 			thread->ptrace_dr7 = val;  in ptrace_set_debugreg()
696 	struct io_bitmap *iobm = target->thread.io_bitmap;  in ioperm_active()
698 	return iobm ? DIV_ROUND_UP(iobm->max, regset->size) : 0;  in ioperm_active()
705 	struct io_bitmap *iobm = target->thread.io_bitmap;  in ioperm_get()
708 		return -ENXIO;  in ioperm_get()
710 	return membuf_write(&to, iobm->bitmap, IO_BITMAP_BYTES);  in ioperm_get()
716  * Make sure the single step bit is not set.
737 	/* This is native 64-bit ptrace() */  in arch_ptrace()
740 	/* This is native 32-bit ptrace() */  in arch_ptrace()
749 		ret = -EIO;  in arch_ptrace()
750 		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))  in arch_ptrace()
758 			addr -= offsetof(struct user, u_debugreg[0]);  in arch_ptrace()
766 		ret = -EIO;  in arch_ptrace()
767 		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))  in arch_ptrace()
774 			addr -= offsetof(struct user, u_debugreg[0]);  in arch_ptrace()
813 					   datap) ? -EIO : 0;  in arch_ptrace()
819 					     datap) ? -EIO : 0;  in arch_ptrace()
825 			return -EIO;  in arch_ptrace()
832 			return -EIO;  in arch_ptrace()
839 		/* normal 64bit interface to access TLS data.  in arch_ptrace()
864 		regs->q = value; break
870 				       value);				\
873 static int putreg32(struct task_struct *child, unsigned regno, u32 value)  in putreg32()  argument
880 	SEG32(cs);  in putreg32()
885 	 * A 32-bit ptracer on a 64-bit kernel expects that writing  in putreg32()
894 				      value);  in putreg32()
896 			child->thread.fsbase =  in putreg32()
897 				x86_fsgsbase_read_task(child, value);  in putreg32()
903 				      value);  in putreg32()
905 			child->thread.gsbase =  in putreg32()
906 				x86_fsgsbase_read_task(child, value);  in putreg32()
923 		 * Warning: bizarre corner case fixup here.  A 32-bit  in putreg32()
924 		 * debugger setting orig_eax to -1 wants to disable  in putreg32()
926 		 * restart code sign-extends orig_ax.  Also make sure  in putreg32()
927 		 * we interpret the -ERESTART* codes correctly if  in putreg32()
928 		 * loaded into regs->ax in case the task is not  in putreg32()
929 		 * actually still sitting at the exit from a 32-bit  in putreg32()
932 		regs->orig_ax = value;  in putreg32()
933 		if (syscall_get_nr(child, regs) != -1)  in putreg32()
934 			child->thread_info.status |= TS_I386_REGS_POKED;  in putreg32()
938 		return set_flags(child, value);  in putreg32()
942 		regno -= offsetof(struct user32, u_debugreg[0]);  in putreg32()
943 		return ptrace_set_debugreg(child, regno / 4, value);  in putreg32()
947 			return -EIO;  in putreg32()
963 		*val = regs->q; break
982 	R32(cs, cs);  in getreg32()
1001 		regno -= offsetof(struct user32, u_debugreg[0]);  in getreg32()
1007 			return -EIO;  in getreg32()
1046 			count -= sizeof(*k);  in genregs32_set()
1057 			count -= sizeof(*u);  in genregs32_set()
1147 		ret = -EIO;  in x32_arch_ptrace()
1148 		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||  in x32_arch_ptrace()
1149 		    addr < offsetof(struct user_regs_struct, cs))  in x32_arch_ptrace()
1157 			addr -= offsetof(struct user, u_debugreg[0]);  in x32_arch_ptrace()
1166 	   zero-extended. */  in x32_arch_ptrace()
1168 		ret = -EIO;  in x32_arch_ptrace()
1169 		if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||  in x32_arch_ptrace()
1170 		    addr < offsetof(struct user_regs_struct, cs))  in x32_arch_ptrace()
1177 			addr -= offsetof(struct user, u_debugreg[0]);  in x32_arch_ptrace()
1379  * regsets.  This is suboptimal if the task is messing around with its CS.L
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
1412 	tsk->thread.trap_nr = X86_TRAP_DB;  in send_sigtrap()
1413 	tsk->thread.error_code = error_code;  in send_sigtrap()
1417 			user_mode(regs) ? (void __user *)regs->ip : NULL);  in send_sigtrap()