Fix a handful of audit-related issue
[sfrench/cifs-2.6.git] / arch / riscv / kernel / ptrace.c
1 /*
2  * Copyright 2010 Tilera Corporation. All Rights Reserved.
3  * Copyright 2015 Regents of the University of California
4  * Copyright 2017 SiFive
5  *
6  *   This program is free software; you can redistribute it and/or
7  *   modify it under the terms of the GNU General Public License
8  *   as published by the Free Software Foundation, version 2.
9  *
10  *   This program is distributed in the hope that it will be useful,
11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *   GNU General Public License for more details.
14  *
15  * Copied from arch/tile/kernel/ptrace.c
16  */
17
18 #include <asm/ptrace.h>
19 #include <asm/syscall.h>
20 #include <asm/thread_info.h>
21 #include <linux/audit.h>
22 #include <linux/ptrace.h>
23 #include <linux/elf.h>
24 #include <linux/regset.h>
25 #include <linux/sched.h>
26 #include <linux/sched/task_stack.h>
27 #include <linux/tracehook.h>
28
29 #define CREATE_TRACE_POINTS
30 #include <trace/events/syscalls.h>
31
32 enum riscv_regset {
33         REGSET_X,
34 #ifdef CONFIG_FPU
35         REGSET_F,
36 #endif
37 };
38
39 static int riscv_gpr_get(struct task_struct *target,
40                          const struct user_regset *regset,
41                          unsigned int pos, unsigned int count,
42                          void *kbuf, void __user *ubuf)
43 {
44         struct pt_regs *regs;
45
46         regs = task_pt_regs(target);
47         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
48 }
49
50 static int riscv_gpr_set(struct task_struct *target,
51                          const struct user_regset *regset,
52                          unsigned int pos, unsigned int count,
53                          const void *kbuf, const void __user *ubuf)
54 {
55         int ret;
56         struct pt_regs *regs;
57
58         regs = task_pt_regs(target);
59         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
60         return ret;
61 }
62
63 #ifdef CONFIG_FPU
64 static int riscv_fpr_get(struct task_struct *target,
65                          const struct user_regset *regset,
66                          unsigned int pos, unsigned int count,
67                          void *kbuf, void __user *ubuf)
68 {
69         int ret;
70         struct __riscv_d_ext_state *fstate = &target->thread.fstate;
71
72         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, fstate, 0,
73                                   offsetof(struct __riscv_d_ext_state, fcsr));
74         if (!ret) {
75                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, fstate, 0,
76                                           offsetof(struct __riscv_d_ext_state, fcsr) +
77                                           sizeof(fstate->fcsr));
78         }
79
80         return ret;
81 }
82
83 static int riscv_fpr_set(struct task_struct *target,
84                          const struct user_regset *regset,
85                          unsigned int pos, unsigned int count,
86                          const void *kbuf, const void __user *ubuf)
87 {
88         int ret;
89         struct __riscv_d_ext_state *fstate = &target->thread.fstate;
90
91         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
92                                  offsetof(struct __riscv_d_ext_state, fcsr));
93         if (!ret) {
94                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
95                                          offsetof(struct __riscv_d_ext_state, fcsr) +
96                                          sizeof(fstate->fcsr));
97         }
98
99         return ret;
100 }
101 #endif
102
103 static const struct user_regset riscv_user_regset[] = {
104         [REGSET_X] = {
105                 .core_note_type = NT_PRSTATUS,
106                 .n = ELF_NGREG,
107                 .size = sizeof(elf_greg_t),
108                 .align = sizeof(elf_greg_t),
109                 .get = &riscv_gpr_get,
110                 .set = &riscv_gpr_set,
111         },
112 #ifdef CONFIG_FPU
113         [REGSET_F] = {
114                 .core_note_type = NT_PRFPREG,
115                 .n = ELF_NFPREG,
116                 .size = sizeof(elf_fpreg_t),
117                 .align = sizeof(elf_fpreg_t),
118                 .get = &riscv_fpr_get,
119                 .set = &riscv_fpr_set,
120         },
121 #endif
122 };
123
124 static const struct user_regset_view riscv_user_native_view = {
125         .name = "riscv",
126         .e_machine = EM_RISCV,
127         .regsets = riscv_user_regset,
128         .n = ARRAY_SIZE(riscv_user_regset),
129 };
130
131 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
132 {
133         return &riscv_user_native_view;
134 }
135
136 void ptrace_disable(struct task_struct *child)
137 {
138         clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
139 }
140
141 long arch_ptrace(struct task_struct *child, long request,
142                  unsigned long addr, unsigned long data)
143 {
144         long ret = -EIO;
145
146         switch (request) {
147         default:
148                 ret = ptrace_request(child, request, addr, data);
149                 break;
150         }
151
152         return ret;
153 }
154
155 /*
156  * Allows PTRACE_SYSCALL to work.  These are called from entry.S in
157  * {handle,ret_from}_syscall.
158  */
159 void do_syscall_trace_enter(struct pt_regs *regs)
160 {
161         if (test_thread_flag(TIF_SYSCALL_TRACE))
162                 if (tracehook_report_syscall_entry(regs))
163                         syscall_set_nr(current, regs, -1);
164
165 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
166         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
167                 trace_sys_enter(regs, syscall_get_nr(current, regs));
168 #endif
169
170         audit_syscall_entry(regs->a7, regs->a0, regs->a1, regs->a2, regs->a3);
171 }
172
173 void do_syscall_trace_exit(struct pt_regs *regs)
174 {
175         audit_syscall_exit(regs);
176
177         if (test_thread_flag(TIF_SYSCALL_TRACE))
178                 tracehook_report_syscall_exit(regs, 0);
179
180 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
181         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
182                 trace_sys_exit(regs, regs_return_value(regs));
183 #endif
184 }