Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * This file is subject to the terms and conditions of the GNU General Public | |
3 | * License. See the file "COPYING" in the main directory of this archive | |
4 | * for more details. | |
5 | * | |
6 | * Copyright (C) 1992 Ross Biro | |
7 | * Copyright (C) Linus Torvalds | |
8 | * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle | |
9 | * Copyright (C) 1996 David S. Miller | |
10 | * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com | |
11 | * Copyright (C) 1999 MIPS Technologies, Inc. | |
12 | * Copyright (C) 2000 Ulf Carlsson | |
13 | * | |
14 | * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit | |
15 | * binaries. | |
16 | */ | |
17 | #include <linux/config.h> | |
18 | #include <linux/compiler.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/sched.h> | |
21 | #include <linux/mm.h> | |
22 | #include <linux/errno.h> | |
23 | #include <linux/ptrace.h> | |
24 | #include <linux/audit.h> | |
25 | #include <linux/smp.h> | |
26 | #include <linux/smp_lock.h> | |
27 | #include <linux/user.h> | |
28 | #include <linux/security.h> | |
7ed20e1a | 29 | #include <linux/signal.h> |
1da177e4 | 30 | |
f8280c8d | 31 | #include <asm/byteorder.h> |
1da177e4 LT |
32 | #include <asm/cpu.h> |
33 | #include <asm/fpu.h> | |
34 | #include <asm/mipsregs.h> | |
35 | #include <asm/pgtable.h> | |
36 | #include <asm/page.h> | |
37 | #include <asm/system.h> | |
38 | #include <asm/uaccess.h> | |
39 | #include <asm/bootinfo.h> | |
40 | ||
41 | /* | |
42 | * Called by kernel/ptrace.c when detaching.. | |
43 | * | |
44 | * Make sure single step bits etc are not set. | |
45 | */ | |
46 | void ptrace_disable(struct task_struct *child) | |
47 | { | |
48 | /* Nothing to do.. */ | |
49 | } | |
50 | ||
51 | asmlinkage int sys_ptrace(long request, long pid, long addr, long data) | |
52 | { | |
53 | struct task_struct *child; | |
54 | int ret; | |
55 | ||
56 | #if 0 | |
57 | printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n", | |
58 | (int) request, (int) pid, (unsigned long) addr, | |
59 | (unsigned long) data); | |
60 | #endif | |
61 | lock_kernel(); | |
62 | ret = -EPERM; | |
63 | if (request == PTRACE_TRACEME) { | |
64 | /* are we already being traced? */ | |
65 | if (current->ptrace & PT_PTRACED) | |
66 | goto out; | |
67 | if ((ret = security_ptrace(current->parent, current))) | |
68 | goto out; | |
69 | /* set the ptrace bit in the process flags. */ | |
70 | current->ptrace |= PT_PTRACED; | |
71 | ret = 0; | |
72 | goto out; | |
73 | } | |
74 | ret = -ESRCH; | |
75 | read_lock(&tasklist_lock); | |
76 | child = find_task_by_pid(pid); | |
77 | if (child) | |
78 | get_task_struct(child); | |
79 | read_unlock(&tasklist_lock); | |
80 | if (!child) | |
81 | goto out; | |
82 | ||
83 | ret = -EPERM; | |
84 | if (pid == 1) /* you may not mess with init */ | |
85 | goto out_tsk; | |
86 | ||
87 | if (request == PTRACE_ATTACH) { | |
88 | ret = ptrace_attach(child); | |
89 | goto out_tsk; | |
90 | } | |
91 | ||
92 | ret = ptrace_check_attach(child, request == PTRACE_KILL); | |
93 | if (ret < 0) | |
94 | goto out_tsk; | |
95 | ||
96 | switch (request) { | |
97 | /* when I and D space are separate, these will need to be fixed. */ | |
98 | case PTRACE_PEEKTEXT: /* read word at location addr. */ | |
99 | case PTRACE_PEEKDATA: { | |
100 | unsigned long tmp; | |
101 | int copied; | |
102 | ||
103 | copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); | |
104 | ret = -EIO; | |
105 | if (copied != sizeof(tmp)) | |
106 | break; | |
fe00f943 | 107 | ret = put_user(tmp,(unsigned long __user *) data); |
1da177e4 LT |
108 | break; |
109 | } | |
110 | ||
111 | /* Read the word at location addr in the USER area. */ | |
112 | case PTRACE_PEEKUSR: { | |
113 | struct pt_regs *regs; | |
114 | unsigned long tmp = 0; | |
115 | ||
116 | regs = (struct pt_regs *) ((unsigned long) child->thread_info + | |
117 | THREAD_SIZE - 32 - sizeof(struct pt_regs)); | |
118 | ret = 0; /* Default return value. */ | |
119 | ||
120 | switch (addr) { | |
121 | case 0 ... 31: | |
122 | tmp = regs->regs[addr]; | |
123 | break; | |
124 | case FPR_BASE ... FPR_BASE + 31: | |
125 | if (tsk_used_math(child)) { | |
126 | fpureg_t *fregs = get_fpu_regs(child); | |
127 | ||
875d43e7 | 128 | #ifdef CONFIG_32BIT |
1da177e4 LT |
129 | /* |
130 | * The odd registers are actually the high | |
131 | * order bits of the values stored in the even | |
132 | * registers - unless we're using r2k_switch.S. | |
133 | */ | |
134 | if (addr & 1) | |
135 | tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32); | |
136 | else | |
137 | tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff); | |
138 | #endif | |
875d43e7 | 139 | #ifdef CONFIG_64BIT |
1da177e4 LT |
140 | tmp = fregs[addr - FPR_BASE]; |
141 | #endif | |
142 | } else { | |
143 | tmp = -1; /* FP not yet used */ | |
144 | } | |
145 | break; | |
146 | case PC: | |
147 | tmp = regs->cp0_epc; | |
148 | break; | |
149 | case CAUSE: | |
150 | tmp = regs->cp0_cause; | |
151 | break; | |
152 | case BADVADDR: | |
153 | tmp = regs->cp0_badvaddr; | |
154 | break; | |
155 | case MMHI: | |
156 | tmp = regs->hi; | |
157 | break; | |
158 | case MMLO: | |
159 | tmp = regs->lo; | |
160 | break; | |
161 | case FPC_CSR: | |
162 | if (cpu_has_fpu) | |
163 | tmp = child->thread.fpu.hard.fcr31; | |
164 | else | |
165 | tmp = child->thread.fpu.soft.fcr31; | |
166 | break; | |
167 | case FPC_EIR: { /* implementation / version register */ | |
168 | unsigned int flags; | |
169 | ||
170 | if (!cpu_has_fpu) | |
171 | break; | |
172 | ||
173 | flags = read_c0_status(); | |
174 | __enable_fpu(); | |
175 | __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp)); | |
176 | write_c0_status(flags); | |
177 | break; | |
178 | } | |
179 | default: | |
180 | tmp = 0; | |
181 | ret = -EIO; | |
182 | goto out_tsk; | |
183 | } | |
fe00f943 | 184 | ret = put_user(tmp, (unsigned long __user *) data); |
1da177e4 LT |
185 | break; |
186 | } | |
187 | ||
188 | /* when I and D space are separate, this will have to be fixed. */ | |
189 | case PTRACE_POKETEXT: /* write the word at location addr. */ | |
190 | case PTRACE_POKEDATA: | |
191 | ret = 0; | |
192 | if (access_process_vm(child, addr, &data, sizeof(data), 1) | |
193 | == sizeof(data)) | |
194 | break; | |
195 | ret = -EIO; | |
196 | break; | |
197 | ||
198 | case PTRACE_POKEUSR: { | |
199 | struct pt_regs *regs; | |
200 | ret = 0; | |
201 | regs = (struct pt_regs *) ((unsigned long) child->thread_info + | |
202 | THREAD_SIZE - 32 - sizeof(struct pt_regs)); | |
203 | ||
204 | switch (addr) { | |
205 | case 0 ... 31: | |
206 | regs->regs[addr] = data; | |
207 | break; | |
208 | case FPR_BASE ... FPR_BASE + 31: { | |
209 | fpureg_t *fregs = get_fpu_regs(child); | |
210 | ||
211 | if (!tsk_used_math(child)) { | |
212 | /* FP not yet used */ | |
213 | memset(&child->thread.fpu.hard, ~0, | |
214 | sizeof(child->thread.fpu.hard)); | |
215 | child->thread.fpu.hard.fcr31 = 0; | |
216 | } | |
875d43e7 | 217 | #ifdef CONFIG_32BIT |
1da177e4 LT |
218 | /* |
219 | * The odd registers are actually the high order bits | |
220 | * of the values stored in the even registers - unless | |
221 | * we're using r2k_switch.S. | |
222 | */ | |
223 | if (addr & 1) { | |
224 | fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff; | |
225 | fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32; | |
226 | } else { | |
227 | fregs[addr - FPR_BASE] &= ~0xffffffffLL; | |
228 | fregs[addr - FPR_BASE] |= data; | |
229 | } | |
230 | #endif | |
875d43e7 | 231 | #ifdef CONFIG_64BIT |
1da177e4 LT |
232 | fregs[addr - FPR_BASE] = data; |
233 | #endif | |
234 | break; | |
235 | } | |
236 | case PC: | |
237 | regs->cp0_epc = data; | |
238 | break; | |
239 | case MMHI: | |
240 | regs->hi = data; | |
241 | break; | |
242 | case MMLO: | |
243 | regs->lo = data; | |
244 | break; | |
245 | case FPC_CSR: | |
246 | if (cpu_has_fpu) | |
247 | child->thread.fpu.hard.fcr31 = data; | |
248 | else | |
249 | child->thread.fpu.soft.fcr31 = data; | |
250 | break; | |
251 | default: | |
252 | /* The rest are not allowed. */ | |
253 | ret = -EIO; | |
254 | break; | |
255 | } | |
256 | break; | |
257 | } | |
258 | ||
259 | case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ | |
260 | case PTRACE_CONT: { /* restart after signal. */ | |
261 | ret = -EIO; | |
7ed20e1a | 262 | if (!valid_signal(data)) |
1da177e4 LT |
263 | break; |
264 | if (request == PTRACE_SYSCALL) { | |
265 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
266 | } | |
267 | else { | |
268 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | |
269 | } | |
270 | child->exit_code = data; | |
271 | wake_up_process(child); | |
272 | ret = 0; | |
273 | break; | |
274 | } | |
275 | ||
276 | /* | |
277 | * make the child exit. Best I can do is send it a sigkill. | |
278 | * perhaps it should be put in the status that it wants to | |
279 | * exit. | |
280 | */ | |
281 | case PTRACE_KILL: | |
282 | ret = 0; | |
283 | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ | |
284 | break; | |
285 | child->exit_code = SIGKILL; | |
286 | wake_up_process(child); | |
287 | break; | |
288 | ||
289 | case PTRACE_DETACH: /* detach a process that was attached. */ | |
290 | ret = ptrace_detach(child, data); | |
291 | break; | |
292 | ||
3c37026d RB |
293 | case PTRACE_GET_THREAD_AREA: |
294 | ret = put_user(child->thread_info->tp_value, | |
295 | (unsigned long __user *) data); | |
296 | break; | |
297 | ||
1da177e4 LT |
298 | default: |
299 | ret = ptrace_request(child, request, addr, data); | |
300 | break; | |
301 | } | |
302 | ||
303 | out_tsk: | |
304 | put_task_struct(child); | |
305 | out: | |
306 | unlock_kernel(); | |
307 | return ret; | |
308 | } | |
309 | ||
67eb81e1 | 310 | static inline int audit_arch(void) |
2fd6f58b | 311 | { |
f8280c8d | 312 | int arch = EM_MIPS; |
875d43e7 | 313 | #ifdef CONFIG_64BIT |
f8280c8d RB |
314 | arch |= __AUDIT_ARCH_64BIT; |
315 | #endif | |
316 | #if defined(__LITTLE_ENDIAN) | |
317 | arch |= __AUDIT_ARCH_LE; | |
318 | #endif | |
319 | return arch; | |
2fd6f58b | 320 | } |
321 | ||
1da177e4 LT |
322 | /* |
323 | * Notification of system call entry/exit | |
324 | * - triggered by current->work.syscall_trace | |
325 | */ | |
326 | asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit) | |
327 | { | |
2fd6f58b | 328 | if (unlikely(current->audit_context) && entryexit) |
f8280c8d RB |
329 | audit_syscall_exit(current, AUDITSC_RESULT(regs->regs[2]), |
330 | regs->regs[2]); | |
1da177e4 | 331 | |
1da177e4 | 332 | if (!(current->ptrace & PT_PTRACED)) |
2fd6f58b | 333 | goto out; |
f8280c8d RB |
334 | if (!test_thread_flag(TIF_SYSCALL_TRACE)) |
335 | goto out; | |
1da177e4 LT |
336 | |
337 | /* The 0x80 provides a way for the tracing parent to distinguish | |
338 | between a syscall stop and SIGTRAP delivery */ | |
339 | ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? | |
340 | 0x80 : 0)); | |
341 | ||
342 | /* | |
343 | * this isn't the same as continuing with a signal, but it will do | |
344 | * for normal use. strace only continues with a signal if the | |
345 | * stopping signal is not SIGTRAP. -brl | |
346 | */ | |
347 | if (current->exit_code) { | |
348 | send_sig(current->exit_code, current, 1); | |
349 | current->exit_code = 0; | |
350 | } | |
2fd6f58b | 351 | out: |
352 | if (unlikely(current->audit_context) && !entryexit) | |
353 | audit_syscall_entry(current, audit_arch(), regs->regs[2], | |
354 | regs->regs[4], regs->regs[5], | |
355 | regs->regs[6], regs->regs[7]); | |
1da177e4 | 356 | } |