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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 ®s->pc, 4*32, 4*33);
68 if (!ret)
69 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
70 ®s->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 ®s->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/elf.h>
26
27#include <asm/thread_info.h>
28#include <asm/page.h>
29
30asmlinkage long do_syscall_trace_enter(struct pt_regs *regs);
31
32asmlinkage void do_syscall_trace_leave(struct pt_regs *regs);
33
34/*
35 * Copy the thread state to a regset that can be interpreted by userspace.
36 *
37 * It doesn't matter what our internal pt_regs structure looks like. The
38 * important thing is that we export a consistent view of the thread state
39 * to userspace. As such, we need to make sure that the regset remains
40 * ABI compatible as defined by the struct user_regs_struct:
41 *
42 * (Each item is a 32-bit word)
43 * r0 = 0 (exported for clarity)
44 * 31 GPRS r1-r31
45 * PC (Program counter)
46 * SR (Supervision register)
47 */
48static int genregs_get(struct task_struct *target,
49 const struct user_regset *regset,
50 struct membuf to)
51{
52 const struct pt_regs *regs = task_pt_regs(target);
53
54 /* r0 */
55 membuf_zero(&to, 4);
56 membuf_write(&to, regs->gpr + 1, 31 * 4);
57 membuf_store(&to, regs->pc);
58 return membuf_store(&to, regs->sr);
59}
60
61/*
62 * Set the thread state from a regset passed in via ptrace
63 */
64static int genregs_set(struct task_struct *target,
65 const struct user_regset *regset,
66 unsigned int pos, unsigned int count,
67 const void *kbuf, const void __user * ubuf)
68{
69 struct pt_regs *regs = task_pt_regs(target);
70 int ret;
71
72 /* ignore r0 */
73 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4);
74 /* r1 - r31 */
75 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
76 regs->gpr+1, 4, 4*32);
77 /* PC */
78 if (!ret)
79 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
80 ®s->pc, 4*32, 4*33);
81 /*
82 * Skip SR and padding... userspace isn't allowed to changes bits in
83 * the Supervision register
84 */
85 if (!ret)
86 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 4*33, -1);
87
88 return ret;
89}
90
91/*
92 * As OpenRISC shares GPRs and floating point registers we don't need to export
93 * the floating point registers again. So here we only export the fpcsr special
94 * purpose register.
95 */
96static int fpregs_get(struct task_struct *target,
97 const struct user_regset *regset,
98 struct membuf to)
99{
100 const struct pt_regs *regs = task_pt_regs(target);
101
102 return membuf_store(&to, regs->fpcsr);
103}
104
105static int fpregs_set(struct task_struct *target,
106 const struct user_regset *regset,
107 unsigned int pos, unsigned int count,
108 const void *kbuf, const void __user *ubuf)
109{
110 struct pt_regs *regs = task_pt_regs(target);
111 int ret;
112
113 /* FPCSR */
114 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
115 ®s->fpcsr, 0, 4);
116 return ret;
117}
118
119/*
120 * Define the register sets available on OpenRISC under Linux
121 */
122enum or1k_regset {
123 REGSET_GENERAL,
124 REGSET_FPU,
125};
126
127static const struct user_regset or1k_regsets[] = {
128 [REGSET_GENERAL] = {
129 .core_note_type = NT_PRSTATUS,
130 .n = ELF_NGREG,
131 .size = sizeof(long),
132 .align = sizeof(long),
133 .regset_get = genregs_get,
134 .set = genregs_set,
135 },
136 [REGSET_FPU] = {
137 .core_note_type = NT_PRFPREG,
138 .n = sizeof(struct __or1k_fpu_state) / sizeof(long),
139 .size = sizeof(long),
140 .align = sizeof(long),
141 .regset_get = fpregs_get,
142 .set = fpregs_set,
143 },
144};
145
146static const struct user_regset_view user_or1k_native_view = {
147 .name = "or1k",
148 .e_machine = EM_OPENRISC,
149 .regsets = or1k_regsets,
150 .n = ARRAY_SIZE(or1k_regsets),
151};
152
153const struct user_regset_view *task_user_regset_view(struct task_struct *task)
154{
155 return &user_or1k_native_view;
156}
157
158/*
159 * does not yet catch signals sent when the child dies.
160 * in exit.c or in signal.c.
161 */
162
163
164/*
165 * Called by kernel/ptrace.c when detaching..
166 *
167 * Make sure the single step bit is not set.
168 */
169void ptrace_disable(struct task_struct *child)
170{
171 pr_debug("ptrace_disable(): TODO\n");
172
173 user_disable_single_step(child);
174 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
175}
176
177long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
178 unsigned long data)
179{
180 int ret;
181
182 switch (request) {
183 default:
184 ret = ptrace_request(child, request, addr, data);
185 break;
186 }
187
188 return ret;
189}
190
191/*
192 * Notification of system call entry/exit
193 * - triggered by current->work.syscall_trace
194 */
195asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
196{
197 long ret = 0;
198
199 if (test_thread_flag(TIF_SYSCALL_TRACE) &&
200 ptrace_report_syscall_entry(regs))
201 /*
202 * Tracing decided this syscall should not happen.
203 * We'll return a bogus call number to get an ENOSYS
204 * error, but leave the original number in <something>.
205 */
206 ret = -1L;
207
208 audit_syscall_entry(regs->gpr[11], regs->gpr[3], regs->gpr[4],
209 regs->gpr[5], regs->gpr[6]);
210
211 return ret ? : regs->gpr[11];
212}
213
214asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
215{
216 int step;
217
218 audit_syscall_exit(regs);
219
220 step = test_thread_flag(TIF_SINGLESTEP);
221 if (step || test_thread_flag(TIF_SYSCALL_TRACE))
222 ptrace_report_syscall_exit(regs, step);
223}