Line data Source code
1 : /*
2 : * Copyright 2003 PathScale, Inc.
3 : * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 : *
5 : * Licensed under the GPL
6 : */
7 :
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 <registers.h>
15 : #include <asm/ptrace-abi.h>
16 :
17 : /*
18 : * determines which flags the user has access to.
19 : * 1 = access 0 = no access
20 : */
21 : #define FLAG_MASK 0x44dd5UL
22 :
23 : static const int reg_offsets[] =
24 : {
25 : [R8 >> 3] = HOST_R8,
26 : [R9 >> 3] = HOST_R9,
27 : [R10 >> 3] = HOST_R10,
28 : [R11 >> 3] = HOST_R11,
29 : [R12 >> 3] = HOST_R12,
30 : [R13 >> 3] = HOST_R13,
31 : [R14 >> 3] = HOST_R14,
32 : [R15 >> 3] = HOST_R15,
33 : [RIP >> 3] = HOST_IP,
34 : [RSP >> 3] = HOST_SP,
35 : [RAX >> 3] = HOST_AX,
36 : [RBX >> 3] = HOST_BX,
37 : [RCX >> 3] = HOST_CX,
38 : [RDX >> 3] = HOST_DX,
39 : [RSI >> 3] = HOST_SI,
40 : [RDI >> 3] = HOST_DI,
41 : [RBP >> 3] = HOST_BP,
42 : [CS >> 3] = HOST_CS,
43 : [SS >> 3] = HOST_SS,
44 : [FS_BASE >> 3] = HOST_FS_BASE,
45 : [GS_BASE >> 3] = HOST_GS_BASE,
46 : [DS >> 3] = HOST_DS,
47 : [ES >> 3] = HOST_ES,
48 : [FS >> 3] = HOST_FS,
49 : [GS >> 3] = HOST_GS,
50 : [EFLAGS >> 3] = HOST_EFLAGS,
51 : [ORIG_RAX >> 3] = HOST_ORIG_AX,
52 : };
53 :
54 0 : int putreg(struct task_struct *child, int regno, unsigned long value)
55 : {
56 0 : switch (regno) {
57 : case R8:
58 : case R9:
59 : case R10:
60 : case R11:
61 : case R12:
62 : case R13:
63 : case R14:
64 : case R15:
65 : case RIP:
66 : case RSP:
67 : case RAX:
68 : case RBX:
69 : case RCX:
70 : case RDX:
71 : case RSI:
72 : case RDI:
73 : case RBP:
74 : break;
75 :
76 : case ORIG_RAX:
77 : /* Update the syscall number. */
78 0 : UPT_SYSCALL_NR(&child->thread.regs.regs) = value;
79 0 : break;
80 :
81 : case FS:
82 : case GS:
83 : case DS:
84 : case ES:
85 : case SS:
86 : case CS:
87 0 : if (value && (value & 3) != 3)
88 : return -EIO;
89 0 : value &= 0xffff;
90 0 : break;
91 :
92 : case FS_BASE:
93 : case GS_BASE:
94 0 : if (!((value >> 48) == 0 || (value >> 48) == 0xffff))
95 : return -EIO;
96 : break;
97 :
98 : case EFLAGS:
99 0 : value &= FLAG_MASK;
100 0 : child->thread.regs.regs.gp[HOST_EFLAGS] |= value;
101 0 : return 0;
102 :
103 : default:
104 0 : panic("Bad register in putreg(): %d\n", regno);
105 : }
106 :
107 0 : child->thread.regs.regs.gp[reg_offsets[regno >> 3]] = value;
108 0 : return 0;
109 : }
110 :
111 0 : int poke_user(struct task_struct *child, long addr, long data)
112 : {
113 0 : if ((addr & 3) || addr < 0)
114 : return -EIO;
115 :
116 0 : if (addr < MAX_REG_OFFSET)
117 0 : return putreg(child, addr, data);
118 0 : else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
119 : (addr <= offsetof(struct user, u_debugreg[7]))) {
120 0 : addr -= offsetof(struct user, u_debugreg[0]);
121 0 : addr = addr >> 3;
122 0 : if ((addr == 4) || (addr == 5))
123 : return -EIO;
124 0 : child->thread.arch.debugregs[addr] = data;
125 0 : return 0;
126 : }
127 : return -EIO;
128 : }
129 :
130 0 : unsigned long getreg(struct task_struct *child, int regno)
131 : {
132 0 : unsigned long mask = ~0UL;
133 :
134 0 : switch (regno) {
135 : case R8:
136 : case R9:
137 : case R10:
138 : case R11:
139 : case R12:
140 : case R13:
141 : case R14:
142 : case R15:
143 : case RIP:
144 : case RSP:
145 : case RAX:
146 : case RBX:
147 : case RCX:
148 : case RDX:
149 : case RSI:
150 : case RDI:
151 : case RBP:
152 : case ORIG_RAX:
153 : case EFLAGS:
154 : case FS_BASE:
155 : case GS_BASE:
156 : break;
157 : case FS:
158 : case GS:
159 : case DS:
160 : case ES:
161 : case SS:
162 : case CS:
163 0 : mask = 0xffff;
164 0 : break;
165 : default:
166 0 : panic("Bad register in getreg: %d\n", regno);
167 : }
168 0 : return mask & child->thread.regs.regs.gp[reg_offsets[regno >> 3]];
169 : }
170 :
171 0 : int peek_user(struct task_struct *child, long addr, long data)
172 : {
173 : /* read the word at location addr in the USER area. */
174 : unsigned long tmp;
175 :
176 0 : if ((addr & 3) || addr < 0)
177 : return -EIO;
178 :
179 0 : tmp = 0; /* Default return condition */
180 0 : if (addr < MAX_REG_OFFSET)
181 0 : tmp = getreg(child, addr);
182 0 : else if ((addr >= offsetof(struct user, u_debugreg[0])) &&
183 : (addr <= offsetof(struct user, u_debugreg[7]))) {
184 0 : addr -= offsetof(struct user, u_debugreg[0]);
185 0 : addr = addr >> 2;
186 0 : tmp = child->thread.arch.debugregs[addr];
187 : }
188 0 : return put_user(tmp, (unsigned long *) data);
189 : }
190 :
191 : /* XXX Mostly copied from sys-i386 */
192 0 : int is_syscall(unsigned long addr)
193 : {
194 : unsigned short instr;
195 : int n;
196 :
197 0 : n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
198 0 : if (n) {
199 : /*
200 : * access_process_vm() grants access to vsyscall and stub,
201 : * while copy_from_user doesn't. Maybe access_process_vm is
202 : * slow, but that doesn't matter, since it will be called only
203 : * in case of singlestepping, if copy_from_user failed.
204 : */
205 0 : n = access_process_vm(current, addr, &instr, sizeof(instr),
206 : FOLL_FORCE);
207 0 : if (n != sizeof(instr)) {
208 0 : printk("is_syscall : failed to read instruction from "
209 : "0x%lx\n", addr);
210 0 : return 1;
211 : }
212 : }
213 : /* sysenter */
214 0 : return instr == 0x050f;
215 : }
216 :
217 0 : static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
218 : {
219 0 : int err, n, cpu = ((struct thread_info *) child->stack)->cpu;
220 : struct user_i387_struct fpregs;
221 :
222 0 : err = save_i387_registers(userspace_pid[cpu],
223 : (unsigned long *) &fpregs);
224 0 : if (err)
225 : return err;
226 :
227 0 : n = copy_to_user(buf, &fpregs, sizeof(fpregs));
228 0 : if (n > 0)
229 : return -EFAULT;
230 :
231 : return n;
232 : }
233 :
234 0 : static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
235 : {
236 0 : int n, cpu = ((struct thread_info *) child->stack)->cpu;
237 : struct user_i387_struct fpregs;
238 :
239 0 : n = copy_from_user(&fpregs, buf, sizeof(fpregs));
240 0 : if (n > 0)
241 : return -EFAULT;
242 :
243 0 : return restore_i387_registers(userspace_pid[cpu],
244 : (unsigned long *) &fpregs);
245 : }
246 :
247 0 : long subarch_ptrace(struct task_struct *child, long request,
248 : unsigned long addr, unsigned long data)
249 : {
250 0 : int ret = -EIO;
251 0 : void __user *datap = (void __user *) data;
252 :
253 0 : switch (request) {
254 : case PTRACE_GETFPREGS: /* Get the child FPU state. */
255 0 : ret = get_fpregs(datap, child);
256 0 : break;
257 : case PTRACE_SETFPREGS: /* Set the child FPU state. */
258 0 : ret = set_fpregs(datap, child);
259 0 : break;
260 : case PTRACE_ARCH_PRCTL:
261 : /* XXX Calls ptrace on the host - needs some SMP thinking */
262 0 : ret = arch_prctl(child, data, (void __user *) addr);
263 0 : break;
264 : }
265 :
266 0 : return ret;
267 : }
|
