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8#include <linux/mm.h>
9#include <linux/sched.h>
10#include <linux/errno.h>
11#define __FRAME_OFFSETS
12#include <asm/ptrace.h>
13#include <linux/uaccess.h>
14#include <asm/ptrace-abi.h>
15
16
17
18
19
20#define FLAG_MASK 0x44dd5UL
21
22static const int reg_offsets[] =
23{
24 [R8 >> 3] = HOST_R8,
25 [R9 >> 3] = HOST_R9,
26 [R10 >> 3] = HOST_R10,
27 [R11 >> 3] = HOST_R11,
28 [R12 >> 3] = HOST_R12,
29 [R13 >> 3] = HOST_R13,
30 [R14 >> 3] = HOST_R14,
31 [R15 >> 3] = HOST_R15,
32 [RIP >> 3] = HOST_IP,
33 [RSP >> 3] = HOST_SP,
34 [RAX >> 3] = HOST_AX,
35 [RBX >> 3] = HOST_BX,
36 [RCX >> 3] = HOST_CX,
37 [RDX >> 3] = HOST_DX,
38 [RSI >> 3] = HOST_SI,
39 [RDI >> 3] = HOST_DI,
40 [RBP >> 3] = HOST_BP,
41 [CS >> 3] = HOST_CS,
42 [SS >> 3] = HOST_SS,
43 [FS_BASE >> 3] = HOST_FS_BASE,
44 [GS_BASE >> 3] = HOST_GS_BASE,
45 [DS >> 3] = HOST_DS,
46 [ES >> 3] = HOST_ES,
47 [FS >> 3] = HOST_FS,
48 [GS >> 3] = HOST_GS,
49 [EFLAGS >> 3] = HOST_EFLAGS,
50 [ORIG_RAX >> 3] = HOST_ORIG_AX,
51};
52
53int putreg(struct task_struct *child, int regno, unsigned long value)
54{
55#ifdef TIF_IA32
56
57
58
59
60 if (test_tsk_thread_flag(child, TIF_IA32))
61 value &= 0xffffffff;
62#endif
63 switch (regno) {
64 case R8:
65 case R9:
66 case R10:
67 case R11:
68 case R12:
69 case R13:
70 case R14:
71 case R15:
72 case RIP:
73 case RSP:
74 case RAX:
75 case RBX:
76 case RCX:
77 case RDX:
78 case RSI:
79 case RDI:
80 case RBP:
81 break;
82
83 case ORIG_RAX:
84
85 UPT_SYSCALL_NR(&child->thread.regs.regs) = value;
86 break;
87
88 case FS:
89 case GS:
90 case DS:
91 case ES:
92 case SS:
93 case CS:
94 if (value && (value & 3) != 3)
95 return -EIO;
96 value &= 0xffff;
97 break;
98
99 case FS_BASE:
100 case GS_BASE:
101 if (!((value >> 48) == 0 || (value >> 48) == 0xffff))
102 return -EIO;
103 break;
104
105 case EFLAGS:
106 value &= FLAG_MASK;
107 child->thread.regs.regs.gp[HOST_EFLAGS] |= value;
108 return 0;
109
110 default:
111 panic("Bad register in putreg(): %d\n", regno);
112 }
113
114 child->thread.regs.regs.gp[reg_offsets[regno >> 3]] = value;
115 return 0;
116}
117
118int poke_user(struct task_struct *child, long addr, long data)
119{
120 if ((addr & 3) || addr < 0)
121 return -EIO;
122
123 if (addr < MAX_REG_OFFSET)
124 return putreg(child, addr, data);
125 else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
126 (addr <= offsetof(struct user, u_debugreg[7]))) {
127 addr -= offsetof(struct user, u_debugreg[0]);
128 addr = addr >> 3;
129 if ((addr == 4) || (addr == 5))
130 return -EIO;
131 child->thread.arch.debugregs[addr] = data;
132 return 0;
133 }
134 return -EIO;
135}
136
137unsigned long getreg(struct task_struct *child, int regno)
138{
139 unsigned long mask = ~0UL;
140#ifdef TIF_IA32
141 if (test_tsk_thread_flag(child, TIF_IA32))
142 mask = 0xffffffff;
143#endif
144 switch (regno) {
145 case R8:
146 case R9:
147 case R10:
148 case R11:
149 case R12:
150 case R13:
151 case R14:
152 case R15:
153 case RIP:
154 case RSP:
155 case RAX:
156 case RBX:
157 case RCX:
158 case RDX:
159 case RSI:
160 case RDI:
161 case RBP:
162 case ORIG_RAX:
163 case EFLAGS:
164 case FS_BASE:
165 case GS_BASE:
166 break;
167 case FS:
168 case GS:
169 case DS:
170 case ES:
171 case SS:
172 case CS:
173 mask = 0xffff;
174 break;
175 default:
176 panic("Bad register in getreg: %d\n", regno);
177 }
178 return mask & child->thread.regs.regs.gp[reg_offsets[regno >> 3]];
179}
180
181int peek_user(struct task_struct *child, long addr, long data)
182{
183
184 unsigned long tmp;
185
186 if ((addr & 3) || addr < 0)
187 return -EIO;
188
189 tmp = 0;
190 if (addr < MAX_REG_OFFSET)
191 tmp = getreg(child, addr);
192 else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
193 (addr <= offsetof(struct user, u_debugreg[7]))) {
194 addr -= offsetof(struct user, u_debugreg[0]);
195 addr = addr >> 2;
196 tmp = child->thread.arch.debugregs[addr];
197 }
198 return put_user(tmp, (unsigned long *) data);
199}
200
201
202int is_syscall(unsigned long addr)
203{
204 unsigned short instr;
205 int n;
206
207 n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
208 if (n) {
209
210
211
212
213
214
215 n = access_process_vm(current, addr, &instr, sizeof(instr),
216 FOLL_FORCE);
217 if (n != sizeof(instr)) {
218 printk("is_syscall : failed to read instruction from "
219 "0x%lx\n", addr);
220 return 1;
221 }
222 }
223
224 return instr == 0x050f;
225}
226
227static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
228{
229 int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
230 struct user_i387_struct fpregs;
231
232 err = save_i387_registers(userspace_pid[cpu],
233 (unsigned long *) &fpregs);
234 if (err)
235 return err;
236
237 n = copy_to_user(buf, &fpregs, sizeof(fpregs));
238 if (n > 0)
239 return -EFAULT;
240
241 return n;
242}
243
244static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
245{
246 int n, cpu = ((struct thread_info *) child->stack)->cpu;
247 struct user_i387_struct fpregs;
248
249 n = copy_from_user(&fpregs, buf, sizeof(fpregs));
250 if (n > 0)
251 return -EFAULT;
252
253 return restore_i387_registers(userspace_pid[cpu],
254 (unsigned long *) &fpregs);
255}
256
257long subarch_ptrace(struct task_struct *child, long request,
258 unsigned long addr, unsigned long data)
259{
260 int ret = -EIO;
261 void __user *datap = (void __user *) data;
262
263 switch (request) {
264 case PTRACE_GETFPREGS:
265 ret = get_fpregs(datap, child);
266 break;
267 case PTRACE_SETFPREGS:
268 ret = set_fpregs(datap, child);
269 break;
270 case PTRACE_ARCH_PRCTL:
271
272 ret = arch_prctl(child, data, (void __user *) addr);
273 break;
274 }
275
276 return ret;
277}
278