1/* 2 * ptrace for 32-bit processes running on a 64-bit kernel. 3 * 4 * PowerPC version 5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 6 * 7 * Derived from "arch/m68k/kernel/ptrace.c" 8 * Copyright (C) 1994 by Hamish Macdonald 9 * Taken from linux/kernel/ptrace.c and modified for M680x0. 10 * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds 11 * 12 * Modified by Cort Dougan (cort@hq.fsmlabs.com) 13 * and Paul Mackerras (paulus@samba.org). 14 * 15 * This file is subject to the terms and conditions of the GNU General 16 * Public License. See the file COPYING in the main directory of 17 * this archive for more details. 18 */ 19 20#include <linux/kernel.h> 21#include <linux/sched.h> 22#include <linux/mm.h> 23#include <linux/smp.h> 24#include <linux/smp_lock.h> 25#include <linux/errno.h> 26#include <linux/ptrace.h> 27#include <linux/user.h> 28#include <linux/security.h> 29#include <linux/signal.h> 30 31#include <asm/uaccess.h> 32#include <asm/page.h> 33#include <asm/pgtable.h> 34#include <asm/system.h> 35 36#include "ptrace-common.h" 37 38/* 39 * does not yet catch signals sent when the child dies. 40 * in exit.c or in signal.c. 41 */ 42 43long compat_sys_ptrace(int request, int pid, unsigned long addr, 44 unsigned long data) 45{ 46 struct task_struct *child; 47 int ret; 48 49 lock_kernel(); 50 if (request == PTRACE_TRACEME) { 51 ret = ptrace_traceme(); 52 goto out; 53 } 54 55 child = ptrace_get_task_struct(pid); 56 if (IS_ERR(child)) { 57 ret = PTR_ERR(child); 58 goto out; 59 } 60 61 if (request == PTRACE_ATTACH) { 62 ret = ptrace_attach(child); 63 goto out_tsk; 64 } 65 66 ret = ptrace_check_attach(child, request == PTRACE_KILL); 67 if (ret < 0) 68 goto out_tsk; 69 70 switch (request) { 71 /* when I and D space are separate, these will need to be fixed. */ 72 case PTRACE_PEEKTEXT: /* read word at location addr. */ 73 case PTRACE_PEEKDATA: { 74 unsigned int tmp; 75 int copied; 76 77 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); 78 ret = -EIO; 79 if (copied != sizeof(tmp)) 80 break; 81 ret = put_user(tmp, (u32 __user *)data); 82 break; 83 } 84 85 /* 86 * Read 4 bytes of the other process' storage 87 * data is a pointer specifying where the user wants the 88 * 4 bytes copied into 89 * addr is a pointer in the user's storage that contains an 8 byte 90 * address in the other process of the 4 bytes that is to be read 91 * (this is run in a 32-bit process looking at a 64-bit process) 92 * when I and D space are separate, these will need to be fixed. 93 */ 94 case PPC_PTRACE_PEEKTEXT_3264: 95 case PPC_PTRACE_PEEKDATA_3264: { 96 u32 tmp; 97 int copied; 98 u32 __user * addrOthers; 99 100 ret = -EIO; 101 102 /* Get the addr in the other process that we want to read */ 103 if (get_user(addrOthers, (u32 __user * __user *)addr) != 0) 104 break; 105 106 copied = access_process_vm(child, (u64)addrOthers, &tmp, 107 sizeof(tmp), 0); 108 if (copied != sizeof(tmp)) 109 break; 110 ret = put_user(tmp, (u32 __user *)data); 111 break; 112 } 113 114 /* Read a register (specified by ADDR) out of the "user area" */ 115 case PTRACE_PEEKUSR: { 116 int index; 117 unsigned long tmp; 118 119 ret = -EIO; 120 /* convert to index and check */ 121 index = (unsigned long) addr >> 2; 122 if ((addr & 3) || (index > PT_FPSCR32)) 123 break; 124 125 if (index < PT_FPR0) { 126 tmp = get_reg(child, index); 127 } else { 128 flush_fp_to_thread(child); 129 /* 130 * the user space code considers the floating point 131 * to be an array of unsigned int (32 bits) - the 132 * index passed in is based on this assumption. 133 */ 134 tmp = ((unsigned int *)child->thread.fpr)[index - PT_FPR0]; 135 } 136 ret = put_user((unsigned int)tmp, (u32 __user *)data); 137 break; 138 } 139 140 /* 141 * Read 4 bytes out of the other process' pt_regs area 142 * data is a pointer specifying where the user wants the 143 * 4 bytes copied into 144 * addr is the offset into the other process' pt_regs structure 145 * that is to be read 146 * (this is run in a 32-bit process looking at a 64-bit process) 147 */ 148 case PPC_PTRACE_PEEKUSR_3264: { 149 u32 index; 150 u32 reg32bits; 151 u64 tmp; 152 u32 numReg; 153 u32 part; 154 155 ret = -EIO; 156 /* Determine which register the user wants */ 157 index = (u64)addr >> 2; 158 numReg = index / 2; 159 /* Determine which part of the register the user wants */ 160 if (index % 2) 161 part = 1; /* want the 2nd half of the register (right-most). */ 162 else 163 part = 0; /* want the 1st half of the register (left-most). */ 164 165 /* Validate the input - check to see if address is on the wrong boundary or beyond the end of the user area */ 166 if ((addr & 3) || numReg > PT_FPSCR) 167 break; 168 169 if (numReg >= PT_FPR0) { 170 flush_fp_to_thread(child); 171 tmp = ((unsigned long int *)child->thread.fpr)[numReg - PT_FPR0]; 172 } else { /* register within PT_REGS struct */ 173 tmp = get_reg(child, numReg); 174 } 175 reg32bits = ((u32*)&tmp)[part]; 176 ret = put_user(reg32bits, (u32 __user *)data); 177 break; 178 } 179 180 /* If I and D space are separate, this will have to be fixed. */ 181 case PTRACE_POKETEXT: /* write the word at location addr. */ 182 case PTRACE_POKEDATA: { 183 unsigned int tmp; 184 tmp = data; 185 ret = 0; 186 if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1) 187 == sizeof(tmp)) 188 break; 189 ret = -EIO; 190 break; 191 } 192 193 /* 194 * Write 4 bytes into the other process' storage 195 * data is the 4 bytes that the user wants written 196 * addr is a pointer in the user's storage that contains an 197 * 8 byte address in the other process where the 4 bytes 198 * that is to be written 199 * (this is run in a 32-bit process looking at a 64-bit process) 200 * when I and D space are separate, these will need to be fixed. 201 */ 202 case PPC_PTRACE_POKETEXT_3264: 203 case PPC_PTRACE_POKEDATA_3264: { 204 u32 tmp = data; 205 u32 __user * addrOthers; 206 207 /* Get the addr in the other process that we want to write into */ 208 ret = -EIO; 209 if (get_user(addrOthers, (u32 __user * __user *)addr) != 0) 210 break; 211 ret = 0; 212 if (access_process_vm(child, (u64)addrOthers, &tmp, 213 sizeof(tmp), 1) == sizeof(tmp)) 214 break; 215 ret = -EIO; 216 break; 217 } 218 219 /* write the word at location addr in the USER area */ 220 case PTRACE_POKEUSR: { 221 unsigned long index; 222 223 ret = -EIO; 224 /* convert to index and check */ 225 index = (unsigned long) addr >> 2; 226 if ((addr & 3) || (index > PT_FPSCR32)) 227 break; 228 229 if (index == PT_ORIG_R3) 230 break; 231 if (index < PT_FPR0) { 232 ret = put_reg(child, index, data); 233 } else { 234 flush_fp_to_thread(child); 235 /* 236 * the user space code considers the floating point 237 * to be an array of unsigned int (32 bits) - the 238 * index passed in is based on this assumption. 239 */ 240 ((unsigned int *)child->thread.fpr)[index - PT_FPR0] = data; 241 ret = 0; 242 } 243 break; 244 } 245 246 /* 247 * Write 4 bytes into the other process' pt_regs area 248 * data is the 4 bytes that the user wants written 249 * addr is the offset into the other process' pt_regs structure 250 * that is to be written into 251 * (this is run in a 32-bit process looking at a 64-bit process) 252 */ 253 case PPC_PTRACE_POKEUSR_3264: { 254 u32 index; 255 u32 numReg; 256 257 ret = -EIO; 258 /* Determine which register the user wants */ 259 index = (u64)addr >> 2; 260 numReg = index / 2; 261 /* 262 * Validate the input - check to see if address is on the 263 * wrong boundary or beyond the end of the user area 264 */ 265 if ((addr & 3) || (numReg > PT_FPSCR)) 266 break; 267 /* Insure it is a register we let them change */ 268 if ((numReg == PT_ORIG_R3) 269 || ((numReg > PT_CCR) && (numReg < PT_FPR0))) 270 break; 271 if (numReg >= PT_FPR0) { 272 flush_fp_to_thread(child); 273 } 274 if (numReg == PT_MSR) 275 data = (data & MSR_DEBUGCHANGE) 276 | (child->thread.regs->msr & ~MSR_DEBUGCHANGE); 277 ((u32*)child->thread.regs)[index] = data; 278 ret = 0; 279 break; 280 } 281 282 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ 283 case PTRACE_CONT: { /* restart after signal. */ 284 ret = -EIO; 285 if (!valid_signal(data)) 286 break; 287 if (request == PTRACE_SYSCALL) 288 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 289 else 290 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 291 child->exit_code = data; 292 /* make sure the single step bit is not set. */ 293 clear_single_step(child); 294 wake_up_process(child); 295 ret = 0; 296 break; 297 } 298 299 /* 300 * make the child exit. Best I can do is send it a sigkill. 301 * perhaps it should be put in the status that it wants to 302 * exit. 303 */ 304 case PTRACE_KILL: { 305 ret = 0; 306 if (child->exit_state == EXIT_ZOMBIE) /* already dead */ 307 break; 308 child->exit_code = SIGKILL; 309 /* make sure the single step bit is not set. */ 310 clear_single_step(child); 311 wake_up_process(child); 312 break; 313 } 314 315 case PTRACE_SINGLESTEP: { /* set the trap flag. */ 316 ret = -EIO; 317 if (!valid_signal(data)) 318 break; 319 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); 320 set_single_step(child); 321 child->exit_code = data; 322 /* give it a chance to run. */ 323 wake_up_process(child); 324 ret = 0; 325 break; 326 } 327 328 case PTRACE_GET_DEBUGREG: { 329 ret = -EINVAL; 330 /* We only support one DABR and no IABRS at the moment */ 331 if (addr > 0) 332 break; 333 ret = put_user(child->thread.dabr, (u32 __user *)data); 334 break; 335 } 336 337 case PTRACE_SET_DEBUGREG: 338 ret = ptrace_set_debugreg(child, addr, data); 339 break; 340 341 case PTRACE_DETACH: 342 ret = ptrace_detach(child, data); 343 break; 344 345 case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */ 346 int i; 347 unsigned long *reg = &((unsigned long *)child->thread.regs)[0]; 348 unsigned int __user *tmp = (unsigned int __user *)addr; 349 350 for (i = 0; i < 32; i++) { 351 ret = put_user(*reg, tmp); 352 if (ret) 353 break; 354 reg++; 355 tmp++; 356 } 357 break; 358 } 359 360 case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */ 361 int i; 362 unsigned long *reg = &((unsigned long *)child->thread.regs)[0]; 363 unsigned int __user *tmp = (unsigned int __user *)addr; 364 365 for (i = 0; i < 32; i++) { 366 ret = get_user(*reg, tmp); 367 if (ret) 368 break; 369 reg++; 370 tmp++; 371 } 372 break; 373 } 374 375 case PPC_PTRACE_GETFPREGS: { /* Get FPRs 0 - 31. */ 376 int i; 377 unsigned long *reg = &((unsigned long *)child->thread.fpr)[0]; 378 unsigned int __user *tmp = (unsigned int __user *)addr; 379 380 flush_fp_to_thread(child); 381 382 for (i = 0; i < 32; i++) { 383 ret = put_user(*reg, tmp); 384 if (ret) 385 break; 386 reg++; 387 tmp++; 388 } 389 break; 390 } 391 392 case PPC_PTRACE_SETFPREGS: { /* Get FPRs 0 - 31. */ 393 int i; 394 unsigned long *reg = &((unsigned long *)child->thread.fpr)[0]; 395 unsigned int __user *tmp = (unsigned int __user *)addr; 396 397 flush_fp_to_thread(child); 398 399 for (i = 0; i < 32; i++) { 400 ret = get_user(*reg, tmp); 401 if (ret) 402 break; 403 reg++; 404 tmp++; 405 } 406 break; 407 } 408 409 case PTRACE_GETEVENTMSG: 410 ret = put_user(child->ptrace_message, (unsigned int __user *) data); 411 break; 412 413#ifdef CONFIG_ALTIVEC 414 case PTRACE_GETVRREGS: 415 /* Get the child altivec register state. */ 416 flush_altivec_to_thread(child); 417 ret = get_vrregs((unsigned long __user *)data, child); 418 break; 419 420 case PTRACE_SETVRREGS: 421 /* Set the child altivec register state. */ 422 flush_altivec_to_thread(child); 423 ret = set_vrregs(child, (unsigned long __user *)data); 424 break; 425#endif 426 427 default: 428 ret = ptrace_request(child, request, addr, data); 429 break; 430 } 431out_tsk: 432 put_task_struct(child); 433out: 434 unlock_kernel(); 435 return ret; 436} 437