Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* ptrace.c: FRV specific parts of process tracing |
| 2 | * |
| 3 | * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * - Derived from arch/m68k/kernel/ptrace.c |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/mm.h> |
| 16 | #include <linux/smp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <linux/errno.h> |
| 18 | #include <linux/ptrace.h> |
| 19 | #include <linux/user.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/security.h> |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 21 | #include <linux/signal.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | #include <asm/uaccess.h> |
| 24 | #include <asm/page.h> |
| 25 | #include <asm/pgtable.h> |
| 26 | #include <asm/system.h> |
| 27 | #include <asm/processor.h> |
| 28 | #include <asm/unistd.h> |
| 29 | |
| 30 | /* |
| 31 | * does not yet catch signals sent when the child dies. |
| 32 | * in exit.c or in signal.c. |
| 33 | */ |
| 34 | |
| 35 | /* |
| 36 | * Get contents of register REGNO in task TASK. |
| 37 | */ |
| 38 | static inline long get_reg(struct task_struct *task, int regno) |
| 39 | { |
| 40 | struct user_context *user = task->thread.user; |
| 41 | |
| 42 | if (regno < 0 || regno >= PT__END) |
| 43 | return 0; |
| 44 | |
| 45 | return ((unsigned long *) user)[regno]; |
| 46 | } |
| 47 | |
| 48 | /* |
| 49 | * Write contents of register REGNO in task TASK. |
| 50 | */ |
| 51 | static inline int put_reg(struct task_struct *task, int regno, |
| 52 | unsigned long data) |
| 53 | { |
| 54 | struct user_context *user = task->thread.user; |
| 55 | |
| 56 | if (regno < 0 || regno >= PT__END) |
| 57 | return -EIO; |
| 58 | |
| 59 | switch (regno) { |
| 60 | case PT_GR(0): |
| 61 | return 0; |
| 62 | case PT_PSR: |
| 63 | case PT__STATUS: |
| 64 | return -EIO; |
| 65 | default: |
| 66 | ((unsigned long *) user)[regno] = data; |
| 67 | return 0; |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | /* |
David Howells | 8feae13 | 2009-01-08 12:04:47 +0000 | [diff] [blame] | 72 | * check that an address falls within the bounds of the target process's memory |
| 73 | * mappings |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | */ |
| 75 | static inline int is_user_addr_valid(struct task_struct *child, |
| 76 | unsigned long start, unsigned long len) |
| 77 | { |
| 78 | #ifdef CONFIG_MMU |
| 79 | if (start >= PAGE_OFFSET || len > PAGE_OFFSET - start) |
| 80 | return -EIO; |
| 81 | return 0; |
| 82 | #else |
David Howells | 8feae13 | 2009-01-08 12:04:47 +0000 | [diff] [blame] | 83 | struct vm_area_struct *vma; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | |
David Howells | 8feae13 | 2009-01-08 12:04:47 +0000 | [diff] [blame] | 85 | vma = find_vma(child->mm, start); |
| 86 | if (vma && start >= vma->vm_start && start + len <= vma->vm_end) |
| 87 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | |
| 89 | return -EIO; |
| 90 | #endif |
| 91 | } |
| 92 | |
| 93 | /* |
| 94 | * Called by kernel/ptrace.c when detaching.. |
| 95 | * |
| 96 | * Control h/w single stepping |
| 97 | */ |
| 98 | void ptrace_disable(struct task_struct *child) |
| 99 | { |
| 100 | child->thread.frame0->__status &= ~REG__STATUS_STEP; |
| 101 | } |
| 102 | |
| 103 | void ptrace_enable(struct task_struct *child) |
| 104 | { |
| 105 | child->thread.frame0->__status |= REG__STATUS_STEP; |
| 106 | } |
| 107 | |
Christoph Hellwig | 481bed4 | 2005-11-07 00:59:47 -0800 | [diff] [blame] | 108 | long arch_ptrace(struct task_struct *child, long request, long addr, long data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | unsigned long tmp; |
| 111 | int ret; |
| 112 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | switch (request) { |
| 114 | /* when I and D space are separate, these will need to be fixed. */ |
| 115 | case PTRACE_PEEKTEXT: /* read word at location addr. */ |
Alexey Dobriyan | 7664732 | 2007-07-17 04:03:43 -0700 | [diff] [blame] | 116 | case PTRACE_PEEKDATA: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | ret = -EIO; |
| 118 | if (is_user_addr_valid(child, addr, sizeof(tmp)) < 0) |
| 119 | break; |
Alexey Dobriyan | 7664732 | 2007-07-17 04:03:43 -0700 | [diff] [blame] | 120 | ret = generic_ptrace_peekdata(child, addr, data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | |
| 123 | /* read the word at location addr in the USER area. */ |
| 124 | case PTRACE_PEEKUSR: { |
| 125 | tmp = 0; |
| 126 | ret = -EIO; |
| 127 | if ((addr & 3) || addr < 0) |
| 128 | break; |
| 129 | |
| 130 | ret = 0; |
| 131 | switch (addr >> 2) { |
| 132 | case 0 ... PT__END - 1: |
| 133 | tmp = get_reg(child, addr >> 2); |
| 134 | break; |
| 135 | |
| 136 | case PT__END + 0: |
| 137 | tmp = child->mm->end_code - child->mm->start_code; |
| 138 | break; |
| 139 | |
| 140 | case PT__END + 1: |
| 141 | tmp = child->mm->end_data - child->mm->start_data; |
| 142 | break; |
| 143 | |
| 144 | case PT__END + 2: |
| 145 | tmp = child->mm->start_stack - child->mm->start_brk; |
| 146 | break; |
| 147 | |
| 148 | case PT__END + 3: |
| 149 | tmp = child->mm->start_code; |
| 150 | break; |
| 151 | |
| 152 | case PT__END + 4: |
| 153 | tmp = child->mm->start_stack; |
| 154 | break; |
| 155 | |
| 156 | default: |
| 157 | ret = -EIO; |
| 158 | break; |
| 159 | } |
| 160 | |
| 161 | if (ret == 0) |
| 162 | ret = put_user(tmp, (unsigned long *) data); |
| 163 | break; |
| 164 | } |
| 165 | |
| 166 | /* when I and D space are separate, this will have to be fixed. */ |
| 167 | case PTRACE_POKETEXT: /* write the word at location addr. */ |
| 168 | case PTRACE_POKEDATA: |
| 169 | ret = -EIO; |
| 170 | if (is_user_addr_valid(child, addr, sizeof(tmp)) < 0) |
| 171 | break; |
Alexey Dobriyan | f284ce7 | 2007-07-17 04:03:44 -0700 | [diff] [blame] | 172 | ret = generic_ptrace_pokedata(child, addr, data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | break; |
| 174 | |
| 175 | case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ |
| 176 | ret = -EIO; |
| 177 | if ((addr & 3) || addr < 0) |
| 178 | break; |
| 179 | |
| 180 | ret = 0; |
| 181 | switch (addr >> 2) { |
| 182 | case 0 ... PT__END-1: |
| 183 | ret = put_reg(child, addr >> 2, data); |
| 184 | break; |
| 185 | |
| 186 | default: |
| 187 | ret = -EIO; |
| 188 | break; |
| 189 | } |
| 190 | break; |
| 191 | |
| 192 | case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ |
| 193 | case PTRACE_CONT: /* restart after signal. */ |
| 194 | ret = -EIO; |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 195 | if (!valid_signal(data)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | break; |
| 197 | if (request == PTRACE_SYSCALL) |
| 198 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 199 | else |
| 200 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 201 | child->exit_code = data; |
| 202 | ptrace_disable(child); |
| 203 | wake_up_process(child); |
| 204 | ret = 0; |
| 205 | break; |
| 206 | |
| 207 | /* make the child exit. Best I can do is send it a sigkill. |
| 208 | * perhaps it should be put in the status that it wants to |
| 209 | * exit. |
| 210 | */ |
| 211 | case PTRACE_KILL: |
| 212 | ret = 0; |
| 213 | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ |
| 214 | break; |
| 215 | child->exit_code = SIGKILL; |
| 216 | clear_tsk_thread_flag(child, TIF_SINGLESTEP); |
| 217 | ptrace_disable(child); |
| 218 | wake_up_process(child); |
| 219 | break; |
| 220 | |
| 221 | case PTRACE_SINGLESTEP: /* set the trap flag. */ |
| 222 | ret = -EIO; |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 223 | if (!valid_signal(data)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | break; |
| 225 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 226 | ptrace_enable(child); |
| 227 | child->exit_code = data; |
| 228 | wake_up_process(child); |
| 229 | ret = 0; |
| 230 | break; |
| 231 | |
| 232 | case PTRACE_DETACH: /* detach a process that was attached. */ |
| 233 | ret = ptrace_detach(child, data); |
| 234 | break; |
| 235 | |
| 236 | case PTRACE_GETREGS: { /* Get all integer regs from the child. */ |
| 237 | int i; |
| 238 | for (i = 0; i < PT__GPEND; i++) { |
| 239 | tmp = get_reg(child, i); |
| 240 | if (put_user(tmp, (unsigned long *) data)) { |
| 241 | ret = -EFAULT; |
| 242 | break; |
| 243 | } |
| 244 | data += sizeof(long); |
| 245 | } |
| 246 | ret = 0; |
| 247 | break; |
| 248 | } |
| 249 | |
| 250 | case PTRACE_SETREGS: { /* Set all integer regs in the child. */ |
| 251 | int i; |
| 252 | for (i = 0; i < PT__GPEND; i++) { |
| 253 | if (get_user(tmp, (unsigned long *) data)) { |
| 254 | ret = -EFAULT; |
| 255 | break; |
| 256 | } |
| 257 | put_reg(child, i, tmp); |
| 258 | data += sizeof(long); |
| 259 | } |
| 260 | ret = 0; |
| 261 | break; |
| 262 | } |
| 263 | |
| 264 | case PTRACE_GETFPREGS: { /* Get the child FP/Media state. */ |
| 265 | ret = 0; |
| 266 | if (copy_to_user((void *) data, |
| 267 | &child->thread.user->f, |
| 268 | sizeof(child->thread.user->f))) |
| 269 | ret = -EFAULT; |
| 270 | break; |
| 271 | } |
| 272 | |
| 273 | case PTRACE_SETFPREGS: { /* Set the child FP/Media state. */ |
| 274 | ret = 0; |
| 275 | if (copy_from_user(&child->thread.user->f, |
| 276 | (void *) data, |
| 277 | sizeof(child->thread.user->f))) |
| 278 | ret = -EFAULT; |
| 279 | break; |
| 280 | } |
| 281 | |
| 282 | case PTRACE_GETFDPIC: |
| 283 | tmp = 0; |
| 284 | switch (addr) { |
| 285 | case PTRACE_GETFDPIC_EXEC: |
| 286 | tmp = child->mm->context.exec_fdpic_loadmap; |
| 287 | break; |
| 288 | case PTRACE_GETFDPIC_INTERP: |
| 289 | tmp = child->mm->context.interp_fdpic_loadmap; |
| 290 | break; |
| 291 | default: |
| 292 | break; |
| 293 | } |
| 294 | |
| 295 | ret = 0; |
| 296 | if (put_user(tmp, (unsigned long *) data)) { |
| 297 | ret = -EFAULT; |
| 298 | break; |
| 299 | } |
| 300 | break; |
| 301 | |
| 302 | default: |
| 303 | ret = -EIO; |
| 304 | break; |
| 305 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | return ret; |
| 307 | } |
| 308 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | asmlinkage void do_syscall_trace(int leaving) |
| 310 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | if (!test_thread_flag(TIF_SYSCALL_TRACE)) |
| 312 | return; |
| 313 | |
| 314 | if (!(current->ptrace & PT_PTRACED)) |
| 315 | return; |
| 316 | |
| 317 | /* we need to indicate entry or exit to strace */ |
| 318 | if (leaving) |
| 319 | __frame->__status |= REG__STATUS_SYSC_EXIT; |
| 320 | else |
| 321 | __frame->__status |= REG__STATUS_SYSC_ENTRY; |
| 322 | |
| 323 | ptrace_notify(SIGTRAP); |
| 324 | |
| 325 | /* |
| 326 | * this isn't the same as continuing with a signal, but it will do |
| 327 | * for normal use. strace only continues with a signal if the |
| 328 | * stopping signal is not SIGTRAP. -brl |
| 329 | */ |
| 330 | if (current->exit_code) { |
| 331 | send_sig(current->exit_code, current, 1); |
| 332 | current->exit_code = 0; |
| 333 | } |
| 334 | } |