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