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 24 enum riscv_regset { 25 REGSET_X, 26 #ifdef CONFIG_FPU 27 REGSET_F, 28 #endif 29 }; 30 31 static 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 42 static 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 56 static 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 75 static 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 95 static 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 }; 115 116 static 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 }; 122 123 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 124 { 125 return &riscv_user_native_view; 126 } 127 128 void ptrace_disable(struct task_struct *child) 129 { 130 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 131 } 132 133 long 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 int 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 return -1; 156 157 /* 158 * Do the secure computing after ptrace; failures should be fast. 159 * If this fails we might have return value in a0 from seccomp 160 * (via SECCOMP_RET_ERRNO/TRACE). 161 */ 162 if (secure_computing() == -1) 163 return -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 return 0; 172 } 173 174 __visible void do_syscall_trace_exit(struct pt_regs *regs) 175 { 176 audit_syscall_exit(regs); 177 178 if (test_thread_flag(TIF_SYSCALL_TRACE)) 179 tracehook_report_syscall_exit(regs, 0); 180 181 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS 182 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) 183 trace_sys_exit(regs, regs_return_value(regs)); 184 #endif 185 } 186