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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 * Copyright 2015 Regents of the University of California
5 * Copyright 2017 SiFive
6 *
7 * Copied from arch/tile/kernel/ptrace.c
8 */
9
10#include <asm/ptrace.h>
11#include <asm/syscall.h>
12#include <asm/thread_info.h>
13#include <linux/audit.h>
14#include <linux/ptrace.h>
15#include <linux/elf.h>
16#include <linux/regset.h>
17#include <linux/sched.h>
18#include <linux/sched/task_stack.h>
19#include <linux/tracehook.h>
20
21#define CREATE_TRACE_POINTS
22#include <trace/events/syscalls.h>
23
24enum riscv_regset {
25 REGSET_X,
26#ifdef CONFIG_FPU
27 REGSET_F,
28#endif
29};
30
31static int riscv_gpr_get(struct task_struct *target,
32 const struct user_regset *regset,
33 unsigned int pos, unsigned int count,
34 void *kbuf, void __user *ubuf)
35{
36 struct pt_regs *regs;
37
38 regs = task_pt_regs(target);
39 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
40}
41
42static int riscv_gpr_set(struct task_struct *target,
43 const struct user_regset *regset,
44 unsigned int pos, unsigned int count,
45 const void *kbuf, const void __user *ubuf)
46{
47 int ret;
48 struct pt_regs *regs;
49
50 regs = task_pt_regs(target);
51 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
52 return ret;
53}
54
55#ifdef CONFIG_FPU
56static int riscv_fpr_get(struct task_struct *target,
57 const struct user_regset *regset,
58 unsigned int pos, unsigned int count,
59 void *kbuf, void __user *ubuf)
60{
61 int ret;
62 struct __riscv_d_ext_state *fstate = &target->thread.fstate;
63
64 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, fstate, 0,
65 offsetof(struct __riscv_d_ext_state, fcsr));
66 if (!ret) {
67 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, fstate, 0,
68 offsetof(struct __riscv_d_ext_state, fcsr) +
69 sizeof(fstate->fcsr));
70 }
71
72 return ret;
73}
74
75static int riscv_fpr_set(struct task_struct *target,
76 const struct user_regset *regset,
77 unsigned int pos, unsigned int count,
78 const void *kbuf, const void __user *ubuf)
79{
80 int ret;
81 struct __riscv_d_ext_state *fstate = &target->thread.fstate;
82
83 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
84 offsetof(struct __riscv_d_ext_state, fcsr));
85 if (!ret) {
86 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
87 offsetof(struct __riscv_d_ext_state, fcsr) +
88 sizeof(fstate->fcsr));
89 }
90
91 return ret;
92}
93#endif
94
95static const struct user_regset riscv_user_regset[] = {
96 [REGSET_X] = {
97 .core_note_type = NT_PRSTATUS,
98 .n = ELF_NGREG,
99 .size = sizeof(elf_greg_t),
100 .align = sizeof(elf_greg_t),
101 .get = &riscv_gpr_get,
102 .set = &riscv_gpr_set,
103 },
104#ifdef CONFIG_FPU
105 [REGSET_F] = {
106 .core_note_type = NT_PRFPREG,
107 .n = ELF_NFPREG,
108 .size = sizeof(elf_fpreg_t),
109 .align = sizeof(elf_fpreg_t),
110 .get = &riscv_fpr_get,
111 .set = &riscv_fpr_set,
112 },
113#endif
114};
115
116static const struct user_regset_view riscv_user_native_view = {
117 .name = "riscv",
118 .e_machine = EM_RISCV,
119 .regsets = riscv_user_regset,
120 .n = ARRAY_SIZE(riscv_user_regset),
121};
122
123const struct user_regset_view *task_user_regset_view(struct task_struct *task)
124{
125 return &riscv_user_native_view;
126}
127
128void ptrace_disable(struct task_struct *child)
129{
130 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
131}
132
133long arch_ptrace(struct task_struct *child, long request,
134 unsigned long addr, unsigned long data)
135{
136 long ret = -EIO;
137
138 switch (request) {
139 default:
140 ret = ptrace_request(child, request, addr, data);
141 break;
142 }
143
144 return ret;
145}
146
147/*
148 * Allows PTRACE_SYSCALL to work. These are called from entry.S in
149 * {handle,ret_from}_syscall.
150 */
151__visible void do_syscall_trace_enter(struct pt_regs *regs)
152{
153 if (test_thread_flag(TIF_SYSCALL_TRACE))
154 if (tracehook_report_syscall_entry(regs))
155 syscall_set_nr(current, regs, -1);
156
157#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
158 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
159 trace_sys_enter(regs, syscall_get_nr(current, regs));
160#endif
161
162 audit_syscall_entry(regs->a7, regs->a0, regs->a1, regs->a2, regs->a3);
163}
164
165__visible void do_syscall_trace_exit(struct pt_regs *regs)
166{
167 audit_syscall_exit(regs);
168
169 if (test_thread_flag(TIF_SYSCALL_TRACE))
170 tracehook_report_syscall_exit(regs, 0);
171
172#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
173 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
174 trace_sys_exit(regs, regs_return_value(regs));
175#endif
176}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 * Copyright 2015 Regents of the University of California
5 * Copyright 2017 SiFive
6 *
7 * Copied from arch/tile/kernel/ptrace.c
8 */
9
10#include <asm/ptrace.h>
11#include <asm/syscall.h>
12#include <asm/thread_info.h>
13#include <asm/switch_to.h>
14#include <linux/audit.h>
15#include <linux/ptrace.h>
16#include <linux/elf.h>
17#include <linux/regset.h>
18#include <linux/sched.h>
19#include <linux/sched/task_stack.h>
20#include <linux/tracehook.h>
21
22#define CREATE_TRACE_POINTS
23#include <trace/events/syscalls.h>
24
25enum riscv_regset {
26 REGSET_X,
27#ifdef CONFIG_FPU
28 REGSET_F,
29#endif
30};
31
32static int riscv_gpr_get(struct task_struct *target,
33 const struct user_regset *regset,
34 struct membuf to)
35{
36 return membuf_write(&to, task_pt_regs(target),
37 sizeof(struct user_regs_struct));
38}
39
40static int riscv_gpr_set(struct task_struct *target,
41 const struct user_regset *regset,
42 unsigned int pos, unsigned int count,
43 const void *kbuf, const void __user *ubuf)
44{
45 int ret;
46 struct pt_regs *regs;
47
48 regs = task_pt_regs(target);
49 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
50 return ret;
51}
52
53#ifdef CONFIG_FPU
54static int riscv_fpr_get(struct task_struct *target,
55 const struct user_regset *regset,
56 struct membuf to)
57{
58 struct __riscv_d_ext_state *fstate = &target->thread.fstate;
59
60 if (target == current)
61 fstate_save(current, task_pt_regs(current));
62
63 membuf_write(&to, fstate, offsetof(struct __riscv_d_ext_state, fcsr));
64 membuf_store(&to, fstate->fcsr);
65 return membuf_zero(&to, 4); // explicitly pad
66}
67
68static int riscv_fpr_set(struct task_struct *target,
69 const struct user_regset *regset,
70 unsigned int pos, unsigned int count,
71 const void *kbuf, const void __user *ubuf)
72{
73 int ret;
74 struct __riscv_d_ext_state *fstate = &target->thread.fstate;
75
76 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
77 offsetof(struct __riscv_d_ext_state, fcsr));
78 if (!ret) {
79 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
80 offsetof(struct __riscv_d_ext_state, fcsr) +
81 sizeof(fstate->fcsr));
82 }
83
84 return ret;
85}
86#endif
87
88static const struct user_regset riscv_user_regset[] = {
89 [REGSET_X] = {
90 .core_note_type = NT_PRSTATUS,
91 .n = ELF_NGREG,
92 .size = sizeof(elf_greg_t),
93 .align = sizeof(elf_greg_t),
94 .regset_get = riscv_gpr_get,
95 .set = riscv_gpr_set,
96 },
97#ifdef CONFIG_FPU
98 [REGSET_F] = {
99 .core_note_type = NT_PRFPREG,
100 .n = ELF_NFPREG,
101 .size = sizeof(elf_fpreg_t),
102 .align = sizeof(elf_fpreg_t),
103 .regset_get = riscv_fpr_get,
104 .set = riscv_fpr_set,
105 },
106#endif
107};
108
109static const struct user_regset_view riscv_user_native_view = {
110 .name = "riscv",
111 .e_machine = EM_RISCV,
112 .regsets = riscv_user_regset,
113 .n = ARRAY_SIZE(riscv_user_regset),
114};
115
116const struct user_regset_view *task_user_regset_view(struct task_struct *task)
117{
118 return &riscv_user_native_view;
119}
120
121struct pt_regs_offset {
122 const char *name;
123 int offset;
124};
125
126#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
127#define REG_OFFSET_END {.name = NULL, .offset = 0}
128
129static const struct pt_regs_offset regoffset_table[] = {
130 REG_OFFSET_NAME(epc),
131 REG_OFFSET_NAME(ra),
132 REG_OFFSET_NAME(sp),
133 REG_OFFSET_NAME(gp),
134 REG_OFFSET_NAME(tp),
135 REG_OFFSET_NAME(t0),
136 REG_OFFSET_NAME(t1),
137 REG_OFFSET_NAME(t2),
138 REG_OFFSET_NAME(s0),
139 REG_OFFSET_NAME(s1),
140 REG_OFFSET_NAME(a0),
141 REG_OFFSET_NAME(a1),
142 REG_OFFSET_NAME(a2),
143 REG_OFFSET_NAME(a3),
144 REG_OFFSET_NAME(a4),
145 REG_OFFSET_NAME(a5),
146 REG_OFFSET_NAME(a6),
147 REG_OFFSET_NAME(a7),
148 REG_OFFSET_NAME(s2),
149 REG_OFFSET_NAME(s3),
150 REG_OFFSET_NAME(s4),
151 REG_OFFSET_NAME(s5),
152 REG_OFFSET_NAME(s6),
153 REG_OFFSET_NAME(s7),
154 REG_OFFSET_NAME(s8),
155 REG_OFFSET_NAME(s9),
156 REG_OFFSET_NAME(s10),
157 REG_OFFSET_NAME(s11),
158 REG_OFFSET_NAME(t3),
159 REG_OFFSET_NAME(t4),
160 REG_OFFSET_NAME(t5),
161 REG_OFFSET_NAME(t6),
162 REG_OFFSET_NAME(status),
163 REG_OFFSET_NAME(badaddr),
164 REG_OFFSET_NAME(cause),
165 REG_OFFSET_NAME(orig_a0),
166 REG_OFFSET_END,
167};
168
169/**
170 * regs_query_register_offset() - query register offset from its name
171 * @name: the name of a register
172 *
173 * regs_query_register_offset() returns the offset of a register in struct
174 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
175 */
176int regs_query_register_offset(const char *name)
177{
178 const struct pt_regs_offset *roff;
179
180 for (roff = regoffset_table; roff->name != NULL; roff++)
181 if (!strcmp(roff->name, name))
182 return roff->offset;
183 return -EINVAL;
184}
185
186/**
187 * regs_within_kernel_stack() - check the address in the stack
188 * @regs: pt_regs which contains kernel stack pointer.
189 * @addr: address which is checked.
190 *
191 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
192 * If @addr is within the kernel stack, it returns true. If not, returns false.
193 */
194static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
195{
196 return (addr & ~(THREAD_SIZE - 1)) ==
197 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
198}
199
200/**
201 * regs_get_kernel_stack_nth() - get Nth entry of the stack
202 * @regs: pt_regs which contains kernel stack pointer.
203 * @n: stack entry number.
204 *
205 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
206 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
207 * this returns 0.
208 */
209unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
210{
211 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
212
213 addr += n;
214 if (regs_within_kernel_stack(regs, (unsigned long)addr))
215 return *addr;
216 else
217 return 0;
218}
219
220void ptrace_disable(struct task_struct *child)
221{
222 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
223}
224
225long arch_ptrace(struct task_struct *child, long request,
226 unsigned long addr, unsigned long data)
227{
228 long ret = -EIO;
229
230 switch (request) {
231 default:
232 ret = ptrace_request(child, request, addr, data);
233 break;
234 }
235
236 return ret;
237}
238
239/*
240 * Allows PTRACE_SYSCALL to work. These are called from entry.S in
241 * {handle,ret_from}_syscall.
242 */
243__visible int do_syscall_trace_enter(struct pt_regs *regs)
244{
245 if (test_thread_flag(TIF_SYSCALL_TRACE))
246 if (tracehook_report_syscall_entry(regs))
247 return -1;
248
249 /*
250 * Do the secure computing after ptrace; failures should be fast.
251 * If this fails we might have return value in a0 from seccomp
252 * (via SECCOMP_RET_ERRNO/TRACE).
253 */
254 if (secure_computing() == -1)
255 return -1;
256
257#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
258 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
259 trace_sys_enter(regs, syscall_get_nr(current, regs));
260#endif
261
262 audit_syscall_entry(regs->a7, regs->a0, regs->a1, regs->a2, regs->a3);
263 return 0;
264}
265
266__visible void do_syscall_trace_exit(struct pt_regs *regs)
267{
268 audit_syscall_exit(regs);
269
270 if (test_thread_flag(TIF_SYSCALL_TRACE))
271 tracehook_report_syscall_exit(regs, 0);
272
273#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
274 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
275 trace_sys_exit(regs, regs_return_value(regs));
276#endif
277}