| 1 | /* |
| 2 | * linux/arch/ppc64/kernel/ptrace32.c |
| 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@linuxcare.com.au). |
| 14 | * |
| 15 | * This file is subject to the terms and conditions of the GNU General |
| 16 | * Public License. See the file README.legal in the main directory of |
| 17 | * this archive for more details. |
| 18 | */ |
| 19 | |
| 20 | #include <linux/config.h> |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/sched.h> |
| 23 | #include <linux/mm.h> |
| 24 | #include <linux/smp.h> |
| 25 | #include <linux/smp_lock.h> |
| 26 | #include <linux/errno.h> |
| 27 | #include <linux/ptrace.h> |
| 28 | #include <linux/user.h> |
| 29 | #include <linux/security.h> |
| 30 | #include <linux/signal.h> |
| 31 | |
| 32 | #include <asm/uaccess.h> |
| 33 | #include <asm/page.h> |
| 34 | #include <asm/pgtable.h> |
| 35 | #include <asm/system.h> |
| 36 | #include <asm/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 | |
| 43 | int compat_sys_ptrace(long request, long pid, unsigned long addr, unsigned long data) |
| 44 | { |
| 45 | struct task_struct *child; |
| 46 | int ret = -EPERM; |
| 47 | |
| 48 | lock_kernel(); |
| 49 | if (request == PTRACE_TRACEME) { |
| 50 | /* are we already being traced? */ |
| 51 | if (current->ptrace & PT_PTRACED) |
| 52 | goto out; |
| 53 | ret = security_ptrace(current->parent, current); |
| 54 | if (ret) |
| 55 | goto out; |
| 56 | /* set the ptrace bit in the process flags. */ |
| 57 | current->ptrace |= PT_PTRACED; |
| 58 | ret = 0; |
| 59 | goto out; |
| 60 | } |
| 61 | ret = -ESRCH; |
| 62 | read_lock(&tasklist_lock); |
| 63 | child = find_task_by_pid(pid); |
| 64 | if (child) |
| 65 | get_task_struct(child); |
| 66 | read_unlock(&tasklist_lock); |
| 67 | if (!child) |
| 68 | goto out; |
| 69 | |
| 70 | ret = -EPERM; |
| 71 | if (pid == 1) /* you may not mess with init */ |
| 72 | goto out_tsk; |
| 73 | |
| 74 | if (request == PTRACE_ATTACH) { |
| 75 | ret = ptrace_attach(child); |
| 76 | goto out_tsk; |
| 77 | } |
| 78 | |
| 79 | ret = ptrace_check_attach(child, request == PTRACE_KILL); |
| 80 | if (ret < 0) |
| 81 | goto out_tsk; |
| 82 | |
| 83 | switch (request) { |
| 84 | /* when I and D space are separate, these will need to be fixed. */ |
| 85 | case PTRACE_PEEKTEXT: /* read word at location addr. */ |
| 86 | case PTRACE_PEEKDATA: { |
| 87 | unsigned int tmp; |
| 88 | int copied; |
| 89 | |
| 90 | copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); |
| 91 | ret = -EIO; |
| 92 | if (copied != sizeof(tmp)) |
| 93 | break; |
| 94 | ret = put_user(tmp, (u32 __user *)data); |
| 95 | break; |
| 96 | } |
| 97 | |
| 98 | /* |
| 99 | * Read 4 bytes of the other process' storage |
| 100 | * data is a pointer specifying where the user wants the |
| 101 | * 4 bytes copied into |
| 102 | * addr is a pointer in the user's storage that contains an 8 byte |
| 103 | * address in the other process of the 4 bytes that is to be read |
| 104 | * (this is run in a 32-bit process looking at a 64-bit process) |
| 105 | * when I and D space are separate, these will need to be fixed. |
| 106 | */ |
| 107 | case PPC_PTRACE_PEEKTEXT_3264: |
| 108 | case PPC_PTRACE_PEEKDATA_3264: { |
| 109 | u32 tmp; |
| 110 | int copied; |
| 111 | u32 __user * addrOthers; |
| 112 | |
| 113 | ret = -EIO; |
| 114 | |
| 115 | /* Get the addr in the other process that we want to read */ |
| 116 | if (get_user(addrOthers, (u32 __user * __user *)addr) != 0) |
| 117 | break; |
| 118 | |
| 119 | copied = access_process_vm(child, (u64)addrOthers, &tmp, |
| 120 | sizeof(tmp), 0); |
| 121 | if (copied != sizeof(tmp)) |
| 122 | break; |
| 123 | ret = put_user(tmp, (u32 __user *)data); |
| 124 | break; |
| 125 | } |
| 126 | |
| 127 | /* Read a register (specified by ADDR) out of the "user area" */ |
| 128 | case PTRACE_PEEKUSR: { |
| 129 | int index; |
| 130 | unsigned long tmp; |
| 131 | |
| 132 | ret = -EIO; |
| 133 | /* convert to index and check */ |
| 134 | index = (unsigned long) addr >> 2; |
| 135 | if ((addr & 3) || (index > PT_FPSCR32)) |
| 136 | break; |
| 137 | |
| 138 | if (index < PT_FPR0) { |
| 139 | tmp = get_reg(child, index); |
| 140 | } else { |
| 141 | flush_fp_to_thread(child); |
| 142 | /* |
| 143 | * the user space code considers the floating point |
| 144 | * to be an array of unsigned int (32 bits) - the |
| 145 | * index passed in is based on this assumption. |
| 146 | */ |
| 147 | tmp = ((unsigned int *)child->thread.fpr)[index - PT_FPR0]; |
| 148 | } |
| 149 | ret = put_user((unsigned int)tmp, (u32 __user *)data); |
| 150 | break; |
| 151 | } |
| 152 | |
| 153 | /* |
| 154 | * Read 4 bytes out of the other process' pt_regs area |
| 155 | * data is a pointer specifying where the user wants the |
| 156 | * 4 bytes copied into |
| 157 | * addr is the offset into the other process' pt_regs structure |
| 158 | * that is to be read |
| 159 | * (this is run in a 32-bit process looking at a 64-bit process) |
| 160 | */ |
| 161 | case PPC_PTRACE_PEEKUSR_3264: { |
| 162 | u32 index; |
| 163 | u32 reg32bits; |
| 164 | u64 tmp; |
| 165 | u32 numReg; |
| 166 | u32 part; |
| 167 | |
| 168 | ret = -EIO; |
| 169 | /* Determine which register the user wants */ |
| 170 | index = (u64)addr >> 2; |
| 171 | numReg = index / 2; |
| 172 | /* Determine which part of the register the user wants */ |
| 173 | if (index % 2) |
| 174 | part = 1; /* want the 2nd half of the register (right-most). */ |
| 175 | else |
| 176 | part = 0; /* want the 1st half of the register (left-most). */ |
| 177 | |
| 178 | /* Validate the input - check to see if address is on the wrong boundary or beyond the end of the user area */ |
| 179 | if ((addr & 3) || numReg > PT_FPSCR) |
| 180 | break; |
| 181 | |
| 182 | if (numReg >= PT_FPR0) { |
| 183 | flush_fp_to_thread(child); |
| 184 | tmp = ((unsigned long int *)child->thread.fpr)[numReg - PT_FPR0]; |
| 185 | } else { /* register within PT_REGS struct */ |
| 186 | tmp = get_reg(child, numReg); |
| 187 | } |
| 188 | reg32bits = ((u32*)&tmp)[part]; |
| 189 | ret = put_user(reg32bits, (u32 __user *)data); |
| 190 | break; |
| 191 | } |
| 192 | |
| 193 | /* If I and D space are separate, this will have to be fixed. */ |
| 194 | case PTRACE_POKETEXT: /* write the word at location addr. */ |
| 195 | case PTRACE_POKEDATA: { |
| 196 | unsigned int tmp; |
| 197 | tmp = data; |
| 198 | ret = 0; |
| 199 | if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1) |
| 200 | == sizeof(tmp)) |
| 201 | break; |
| 202 | ret = -EIO; |
| 203 | break; |
| 204 | } |
| 205 | |
| 206 | /* |
| 207 | * Write 4 bytes into the other process' storage |
| 208 | * data is the 4 bytes that the user wants written |
| 209 | * addr is a pointer in the user's storage that contains an |
| 210 | * 8 byte address in the other process where the 4 bytes |
| 211 | * that is to be written |
| 212 | * (this is run in a 32-bit process looking at a 64-bit process) |
| 213 | * when I and D space are separate, these will need to be fixed. |
| 214 | */ |
| 215 | case PPC_PTRACE_POKETEXT_3264: |
| 216 | case PPC_PTRACE_POKEDATA_3264: { |
| 217 | u32 tmp = data; |
| 218 | u32 __user * addrOthers; |
| 219 | |
| 220 | /* Get the addr in the other process that we want to write into */ |
| 221 | ret = -EIO; |
| 222 | if (get_user(addrOthers, (u32 __user * __user *)addr) != 0) |
| 223 | break; |
| 224 | ret = 0; |
| 225 | if (access_process_vm(child, (u64)addrOthers, &tmp, |
| 226 | sizeof(tmp), 1) == sizeof(tmp)) |
| 227 | break; |
| 228 | ret = -EIO; |
| 229 | break; |
| 230 | } |
| 231 | |
| 232 | /* write the word at location addr in the USER area */ |
| 233 | case PTRACE_POKEUSR: { |
| 234 | unsigned long index; |
| 235 | |
| 236 | ret = -EIO; |
| 237 | /* convert to index and check */ |
| 238 | index = (unsigned long) addr >> 2; |
| 239 | if ((addr & 3) || (index > PT_FPSCR32)) |
| 240 | break; |
| 241 | |
| 242 | if (index == PT_ORIG_R3) |
| 243 | break; |
| 244 | if (index < PT_FPR0) { |
| 245 | ret = put_reg(child, index, data); |
| 246 | } else { |
| 247 | flush_fp_to_thread(child); |
| 248 | /* |
| 249 | * the user space code considers the floating point |
| 250 | * to be an array of unsigned int (32 bits) - the |
| 251 | * index passed in is based on this assumption. |
| 252 | */ |
| 253 | ((unsigned int *)child->thread.fpr)[index - PT_FPR0] = data; |
| 254 | ret = 0; |
| 255 | } |
| 256 | break; |
| 257 | } |
| 258 | |
| 259 | /* |
| 260 | * Write 4 bytes into the other process' pt_regs area |
| 261 | * data is the 4 bytes that the user wants written |
| 262 | * addr is the offset into the other process' pt_regs structure |
| 263 | * that is to be written into |
| 264 | * (this is run in a 32-bit process looking at a 64-bit process) |
| 265 | */ |
| 266 | case PPC_PTRACE_POKEUSR_3264: { |
| 267 | u32 index; |
| 268 | u32 numReg; |
| 269 | |
| 270 | ret = -EIO; |
| 271 | /* Determine which register the user wants */ |
| 272 | index = (u64)addr >> 2; |
| 273 | numReg = index / 2; |
| 274 | /* |
| 275 | * Validate the input - check to see if address is on the |
| 276 | * wrong boundary or beyond the end of the user area |
| 277 | */ |
| 278 | if ((addr & 3) || (numReg > PT_FPSCR)) |
| 279 | break; |
| 280 | /* Insure it is a register we let them change */ |
| 281 | if ((numReg == PT_ORIG_R3) |
| 282 | || ((numReg > PT_CCR) && (numReg < PT_FPR0))) |
| 283 | break; |
| 284 | if (numReg >= PT_FPR0) { |
| 285 | flush_fp_to_thread(child); |
| 286 | } |
| 287 | if (numReg == PT_MSR) |
| 288 | data = (data & MSR_DEBUGCHANGE) |
| 289 | | (child->thread.regs->msr & ~MSR_DEBUGCHANGE); |
| 290 | ((u32*)child->thread.regs)[index] = data; |
| 291 | ret = 0; |
| 292 | break; |
| 293 | } |
| 294 | |
| 295 | case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ |
| 296 | case PTRACE_CONT: { /* restart after signal. */ |
| 297 | ret = -EIO; |
| 298 | if (!valid_signal(data)) |
| 299 | break; |
| 300 | if (request == PTRACE_SYSCALL) |
| 301 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 302 | else |
| 303 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 304 | child->exit_code = data; |
| 305 | /* make sure the single step bit is not set. */ |
| 306 | clear_single_step(child); |
| 307 | wake_up_process(child); |
| 308 | ret = 0; |
| 309 | break; |
| 310 | } |
| 311 | |
| 312 | /* |
| 313 | * make the child exit. Best I can do is send it a sigkill. |
| 314 | * perhaps it should be put in the status that it wants to |
| 315 | * exit. |
| 316 | */ |
| 317 | case PTRACE_KILL: { |
| 318 | ret = 0; |
| 319 | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ |
| 320 | break; |
| 321 | child->exit_code = SIGKILL; |
| 322 | /* make sure the single step bit is not set. */ |
| 323 | clear_single_step(child); |
| 324 | wake_up_process(child); |
| 325 | break; |
| 326 | } |
| 327 | |
| 328 | case PTRACE_SINGLESTEP: { /* set the trap flag. */ |
| 329 | ret = -EIO; |
| 330 | if (!valid_signal(data)) |
| 331 | break; |
| 332 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 333 | set_single_step(child); |
| 334 | child->exit_code = data; |
| 335 | /* give it a chance to run. */ |
| 336 | wake_up_process(child); |
| 337 | ret = 0; |
| 338 | break; |
| 339 | } |
| 340 | |
| 341 | case PTRACE_GET_DEBUGREG: { |
| 342 | ret = -EINVAL; |
| 343 | /* We only support one DABR and no IABRS at the moment */ |
| 344 | if (addr > 0) |
| 345 | break; |
| 346 | ret = put_user(child->thread.dabr, (u32 __user *)data); |
| 347 | break; |
| 348 | } |
| 349 | |
| 350 | case PTRACE_SET_DEBUGREG: |
| 351 | ret = ptrace_set_debugreg(child, addr, data); |
| 352 | break; |
| 353 | |
| 354 | case PTRACE_DETACH: |
| 355 | ret = ptrace_detach(child, data); |
| 356 | break; |
| 357 | |
| 358 | case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */ |
| 359 | int i; |
| 360 | unsigned long *reg = &((unsigned long *)child->thread.regs)[0]; |
| 361 | unsigned int __user *tmp = (unsigned int __user *)addr; |
| 362 | |
| 363 | for (i = 0; i < 32; i++) { |
| 364 | ret = put_user(*reg, tmp); |
| 365 | if (ret) |
| 366 | break; |
| 367 | reg++; |
| 368 | tmp++; |
| 369 | } |
| 370 | break; |
| 371 | } |
| 372 | |
| 373 | case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */ |
| 374 | int i; |
| 375 | unsigned long *reg = &((unsigned long *)child->thread.regs)[0]; |
| 376 | unsigned int __user *tmp = (unsigned int __user *)addr; |
| 377 | |
| 378 | for (i = 0; i < 32; i++) { |
| 379 | ret = get_user(*reg, tmp); |
| 380 | if (ret) |
| 381 | break; |
| 382 | reg++; |
| 383 | tmp++; |
| 384 | } |
| 385 | break; |
| 386 | } |
| 387 | |
| 388 | case PPC_PTRACE_GETFPREGS: { /* Get FPRs 0 - 31. */ |
| 389 | int i; |
| 390 | unsigned long *reg = &((unsigned long *)child->thread.fpr)[0]; |
| 391 | unsigned int __user *tmp = (unsigned int __user *)addr; |
| 392 | |
| 393 | flush_fp_to_thread(child); |
| 394 | |
| 395 | for (i = 0; i < 32; i++) { |
| 396 | ret = put_user(*reg, tmp); |
| 397 | if (ret) |
| 398 | break; |
| 399 | reg++; |
| 400 | tmp++; |
| 401 | } |
| 402 | break; |
| 403 | } |
| 404 | |
| 405 | case PPC_PTRACE_SETFPREGS: { /* Get FPRs 0 - 31. */ |
| 406 | int i; |
| 407 | unsigned long *reg = &((unsigned long *)child->thread.fpr)[0]; |
| 408 | unsigned int __user *tmp = (unsigned int __user *)addr; |
| 409 | |
| 410 | flush_fp_to_thread(child); |
| 411 | |
| 412 | for (i = 0; i < 32; i++) { |
| 413 | ret = get_user(*reg, tmp); |
| 414 | if (ret) |
| 415 | break; |
| 416 | reg++; |
| 417 | tmp++; |
| 418 | } |
| 419 | break; |
| 420 | } |
| 421 | |
| 422 | case PTRACE_GETEVENTMSG: |
| 423 | ret = put_user(child->ptrace_message, (unsigned int __user *) data); |
| 424 | break; |
| 425 | |
| 426 | #ifdef CONFIG_ALTIVEC |
| 427 | case PTRACE_GETVRREGS: |
| 428 | /* Get the child altivec register state. */ |
| 429 | flush_altivec_to_thread(child); |
| 430 | ret = get_vrregs((unsigned long __user *)data, child); |
| 431 | break; |
| 432 | |
| 433 | case PTRACE_SETVRREGS: |
| 434 | /* Set the child altivec register state. */ |
| 435 | flush_altivec_to_thread(child); |
| 436 | ret = set_vrregs(child, (unsigned long __user *)data); |
| 437 | break; |
| 438 | #endif |
| 439 | |
| 440 | default: |
| 441 | ret = ptrace_request(child, request, addr, data); |
| 442 | break; |
| 443 | } |
| 444 | out_tsk: |
| 445 | put_task_struct(child); |
| 446 | out: |
| 447 | unlock_kernel(); |
| 448 | return ret; |
| 449 | } |