1/*
  2 * OpenRISC ptrace.c
  3 *
  4 * Linux architectural port borrowing liberally from similar works of
  5 * others.  All original copyrights apply as per the original source
  6 * declaration.
  7 *
  8 * Modifications for the OpenRISC architecture:
  9 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
 10 * Copyright (C) 2005 Gyorgy Jeney <nog@bsemi.com>
 11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
 12 *
 13 *      This program is free software; you can redistribute it and/or
 14 *      modify it under the terms of the GNU General Public License
 15 *      as published by the Free Software Foundation; either version
 16 *      2 of the License, or (at your option) any later version.
 17 */
 18
 19#include <linux/kernel.h>
 20#include <linux/sched.h>
 21#include <linux/sched/task_stack.h>
 22#include <linux/string.h>
 23
 24#include <linux/mm.h>
 25#include <linux/errno.h>
 26#include <linux/ptrace.h>
 27#include <linux/audit.h>
 28#include <linux/regset.h>
 29#include <linux/tracehook.h>
 30#include <linux/elf.h>
 31
 32#include <asm/thread_info.h>
 33#include <asm/segment.h>
 34#include <asm/page.h>
 35#include <asm/pgtable.h>
 36
 37/*
 38 * Copy the thread state to a regset that can be interpreted by userspace.
 39 *
 40 * It doesn't matter what our internal pt_regs structure looks like.  The
 41 * important thing is that we export a consistent view of the thread state
 42 * to userspace.  As such, we need to make sure that the regset remains
 43 * ABI compatible as defined by the struct user_regs_struct:
 44 *
 45 * (Each item is a 32-bit word)
 46 * r0 = 0 (exported for clarity)
 47 * 31 GPRS r1-r31
 48 * PC (Program counter)
 49 * SR (Supervision register)
 50 */
 51static int genregs_get(struct task_struct *target,
 52		       const struct user_regset *regset,
 53		       unsigned int pos, unsigned int count,
 54		       void *kbuf, void __user * ubuf)
 55{
 56	const struct pt_regs *regs = task_pt_regs(target);
 57	int ret;
 58
 59	/* r0 */
 60	ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, 0, 4);
 61
 62	if (!ret)
 63		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 64					  regs->gpr+1, 4, 4*32);
 65	if (!ret)
 66		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 67				  &regs->pc, 4*32, 4*33);
 68	if (!ret)
 69		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 70					  &regs->sr, 4*33, 4*34);
 71	if (!ret)
 72		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 73					       4*34, -1);
 74
 75	return ret;
 76}
 77
 78/*
 79 * Set the thread state from a regset passed in via ptrace
 80 */
 81static int genregs_set(struct task_struct *target,
 82		       const struct user_regset *regset,
 83		       unsigned int pos, unsigned int count,
 84		       const void *kbuf, const void __user * ubuf)
 85{
 86	struct pt_regs *regs = task_pt_regs(target);
 87	int ret;
 88
 89	/* ignore r0 */
 90	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4);
 91	/* r1 - r31 */
 92	if (!ret)
 93		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 94					 regs->gpr+1, 4, 4*32);
 95	/* PC */
 96	if (!ret)
 97		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 98				 &regs->pc, 4*32, 4*33);
 99	/*
100	 * Skip SR and padding... userspace isn't allowed to changes bits in
101	 * the Supervision register
102	 */
103	if (!ret)
104		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
105						4*33, -1);
106
107	return ret;
108}
109
110/*
111 * Define the register sets available on OpenRISC under Linux
112 */
113enum or1k_regset {
114	REGSET_GENERAL,
115};
116
117static const struct user_regset or1k_regsets[] = {
118	[REGSET_GENERAL] = {
119			    .core_note_type = NT_PRSTATUS,
120			    .n = ELF_NGREG,
121			    .size = sizeof(long),
122			    .align = sizeof(long),
123			    .get = genregs_get,
124			    .set = genregs_set,
125			    },
126};
127
128static const struct user_regset_view user_or1k_native_view = {
129	.name = "or1k",
130	.e_machine = EM_OPENRISC,
131	.regsets = or1k_regsets,
132	.n = ARRAY_SIZE(or1k_regsets),
133};
134
135const struct user_regset_view *task_user_regset_view(struct task_struct *task)
136{
137	return &user_or1k_native_view;
138}
139
140/*
141 * does not yet catch signals sent when the child dies.
142 * in exit.c or in signal.c.
143 */
144
145
146/*
147 * Called by kernel/ptrace.c when detaching..
148 *
149 * Make sure the single step bit is not set.
150 */
151void ptrace_disable(struct task_struct *child)
152{
153	pr_debug("ptrace_disable(): TODO\n");
154
155	user_disable_single_step(child);
156	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
157}
158
159long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
160		 unsigned long data)
161{
162	int ret;
163
164	switch (request) {
165	default:
166		ret = ptrace_request(child, request, addr, data);
167		break;
168	}
169
170	return ret;
171}
172
173/*
174 * Notification of system call entry/exit
175 * - triggered by current->work.syscall_trace
176 */
177asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
178{
179	long ret = 0;
180
181	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
182	    tracehook_report_syscall_entry(regs))
183		/*
184		 * Tracing decided this syscall should not happen.
185		 * We'll return a bogus call number to get an ENOSYS
186		 * error, but leave the original number in <something>.
187		 */
188		ret = -1L;
189
190	audit_syscall_entry(regs->gpr[11], regs->gpr[3], regs->gpr[4],
191			    regs->gpr[5], regs->gpr[6]);
192
193	return ret ? : regs->gpr[11];
194}
195
196asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
197{
198	int step;
199
200	audit_syscall_exit(regs);
201
202	step = test_thread_flag(TIF_SINGLESTEP);
203	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
204		tracehook_report_syscall_exit(regs, step);
205}

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * OpenRISC ptrace.c
  4 *
  5 * Linux architectural port borrowing liberally from similar works of
  6 * others.  All original copyrights apply as per the original source
  7 * declaration.
  8 *
  9 * Modifications for the OpenRISC architecture:
 10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
 11 * Copyright (C) 2005 Gyorgy Jeney <nog@bsemi.com>
 12 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
 
 
 
 
 
 13 */
 14
 15#include <linux/kernel.h>
 16#include <linux/sched.h>
 17#include <linux/sched/task_stack.h>
 18#include <linux/string.h>
 19
 20#include <linux/mm.h>
 21#include <linux/errno.h>
 22#include <linux/ptrace.h>
 23#include <linux/audit.h>
 24#include <linux/regset.h>
 25#include <linux/tracehook.h>
 26#include <linux/elf.h>
 27
 28#include <asm/thread_info.h>
 
 29#include <asm/page.h>
 30#include <asm/pgtable.h>
 31
 32/*
 33 * Copy the thread state to a regset that can be interpreted by userspace.
 34 *
 35 * It doesn't matter what our internal pt_regs structure looks like.  The
 36 * important thing is that we export a consistent view of the thread state
 37 * to userspace.  As such, we need to make sure that the regset remains
 38 * ABI compatible as defined by the struct user_regs_struct:
 39 *
 40 * (Each item is a 32-bit word)
 41 * r0 = 0 (exported for clarity)
 42 * 31 GPRS r1-r31
 43 * PC (Program counter)
 44 * SR (Supervision register)
 45 */
 46static int genregs_get(struct task_struct *target,
 47		       const struct user_regset *regset,
 48		       unsigned int pos, unsigned int count,
 49		       void *kbuf, void __user * ubuf)
 50{
 51	const struct pt_regs *regs = task_pt_regs(target);
 52	int ret;
 53
 54	/* r0 */
 55	ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, 0, 4);
 56
 57	if (!ret)
 58		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 59					  regs->gpr+1, 4, 4*32);
 60	if (!ret)
 61		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 62				  &regs->pc, 4*32, 4*33);
 63	if (!ret)
 64		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 65					  &regs->sr, 4*33, 4*34);
 66	if (!ret)
 67		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 68					       4*34, -1);
 69
 70	return ret;
 71}
 72
 73/*
 74 * Set the thread state from a regset passed in via ptrace
 75 */
 76static int genregs_set(struct task_struct *target,
 77		       const struct user_regset *regset,
 78		       unsigned int pos, unsigned int count,
 79		       const void *kbuf, const void __user * ubuf)
 80{
 81	struct pt_regs *regs = task_pt_regs(target);
 82	int ret;
 83
 84	/* ignore r0 */
 85	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4);
 86	/* r1 - r31 */
 87	if (!ret)
 88		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 89					 regs->gpr+1, 4, 4*32);
 90	/* PC */
 91	if (!ret)
 92		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 93				 &regs->pc, 4*32, 4*33);
 94	/*
 95	 * Skip SR and padding... userspace isn't allowed to changes bits in
 96	 * the Supervision register
 97	 */
 98	if (!ret)
 99		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
100						4*33, -1);
101
102	return ret;
103}
104
105/*
106 * Define the register sets available on OpenRISC under Linux
107 */
108enum or1k_regset {
109	REGSET_GENERAL,
110};
111
112static const struct user_regset or1k_regsets[] = {
113	[REGSET_GENERAL] = {
114			    .core_note_type = NT_PRSTATUS,
115			    .n = ELF_NGREG,
116			    .size = sizeof(long),
117			    .align = sizeof(long),
118			    .get = genregs_get,
119			    .set = genregs_set,
120			    },
121};
122
123static const struct user_regset_view user_or1k_native_view = {
124	.name = "or1k",
125	.e_machine = EM_OPENRISC,
126	.regsets = or1k_regsets,
127	.n = ARRAY_SIZE(or1k_regsets),
128};
129
130const struct user_regset_view *task_user_regset_view(struct task_struct *task)
131{
132	return &user_or1k_native_view;
133}
134
135/*
136 * does not yet catch signals sent when the child dies.
137 * in exit.c or in signal.c.
138 */
139
140
141/*
142 * Called by kernel/ptrace.c when detaching..
143 *
144 * Make sure the single step bit is not set.
145 */
146void ptrace_disable(struct task_struct *child)
147{
148	pr_debug("ptrace_disable(): TODO\n");
149
150	user_disable_single_step(child);
151	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
152}
153
154long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
155		 unsigned long data)
156{
157	int ret;
158
159	switch (request) {
160	default:
161		ret = ptrace_request(child, request, addr, data);
162		break;
163	}
164
165	return ret;
166}
167
168/*
169 * Notification of system call entry/exit
170 * - triggered by current->work.syscall_trace
171 */
172asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
173{
174	long ret = 0;
175
176	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
177	    tracehook_report_syscall_entry(regs))
178		/*
179		 * Tracing decided this syscall should not happen.
180		 * We'll return a bogus call number to get an ENOSYS
181		 * error, but leave the original number in <something>.
182		 */
183		ret = -1L;
184
185	audit_syscall_entry(regs->gpr[11], regs->gpr[3], regs->gpr[4],
186			    regs->gpr[5], regs->gpr[6]);
187
188	return ret ? : regs->gpr[11];
189}
190
191asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
192{
193	int step;
194
195	audit_syscall_exit(regs);
196
197	step = test_thread_flag(TIF_SINGLESTEP);
198	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
199		tracehook_report_syscall_exit(regs, step);
200}