1/* 2 * comedi/comedi_compat32.c 3 * 32-bit ioctl compatibility for 64-bit comedi kernel module. 4 * 5 * Author: Ian Abbott, MEV Ltd. <abbotti@mev.co.uk> 6 * Copyright (C) 2007 MEV Ltd. <http://www.mev.co.uk/> 7 * 8 * COMEDI - Linux Control and Measurement Device Interface 9 * Copyright (C) 1997-2007 David A. Schleef <ds@schleef.org> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 */ 21 22#include <linux/uaccess.h> 23#include <linux/compat.h> 24#include <linux/fs.h> 25#include "comedi.h" 26#include "comedi_compat32.h" 27 28#define COMEDI32_CHANINFO _IOR(CIO, 3, struct comedi32_chaninfo_struct) 29#define COMEDI32_RANGEINFO _IOR(CIO, 8, struct comedi32_rangeinfo_struct) 30/* 31 * N.B. COMEDI32_CMD and COMEDI_CMD ought to use _IOWR, not _IOR. 32 * It's too late to change it now, but it only affects the command number. 33 */ 34#define COMEDI32_CMD _IOR(CIO, 9, struct comedi32_cmd_struct) 35/* 36 * N.B. COMEDI32_CMDTEST and COMEDI_CMDTEST ought to use _IOWR, not _IOR. 37 * It's too late to change it now, but it only affects the command number. 38 */ 39#define COMEDI32_CMDTEST _IOR(CIO, 10, struct comedi32_cmd_struct) 40#define COMEDI32_INSNLIST _IOR(CIO, 11, struct comedi32_insnlist_struct) 41#define COMEDI32_INSN _IOR(CIO, 12, struct comedi32_insn_struct) 42 43struct comedi32_chaninfo_struct { 44 unsigned int subdev; 45 compat_uptr_t maxdata_list; /* 32-bit 'unsigned int *' */ 46 compat_uptr_t flaglist; /* 32-bit 'unsigned int *' */ 47 compat_uptr_t rangelist; /* 32-bit 'unsigned int *' */ 48 unsigned int unused[4]; 49}; 50 51struct comedi32_rangeinfo_struct { 52 unsigned int range_type; 53 compat_uptr_t range_ptr; /* 32-bit 'void *' */ 54}; 55 56struct comedi32_cmd_struct { 57 unsigned int subdev; 58 unsigned int flags; 59 unsigned int start_src; 60 unsigned int start_arg; 61 unsigned int scan_begin_src; 62 unsigned int scan_begin_arg; 63 unsigned int convert_src; 64 unsigned int convert_arg; 65 unsigned int scan_end_src; 66 unsigned int scan_end_arg; 67 unsigned int stop_src; 68 unsigned int stop_arg; 69 compat_uptr_t chanlist; /* 32-bit 'unsigned int *' */ 70 unsigned int chanlist_len; 71 compat_uptr_t data; /* 32-bit 'short *' */ 72 unsigned int data_len; 73}; 74 75struct comedi32_insn_struct { 76 unsigned int insn; 77 unsigned int n; 78 compat_uptr_t data; /* 32-bit 'unsigned int *' */ 79 unsigned int subdev; 80 unsigned int chanspec; 81 unsigned int unused[3]; 82}; 83 84struct comedi32_insnlist_struct { 85 unsigned int n_insns; 86 compat_uptr_t insns; /* 32-bit 'struct comedi_insn *' */ 87}; 88 89/* Handle translated ioctl. */ 90static int translated_ioctl(struct file *file, unsigned int cmd, 91 unsigned long arg) 92{ 93 if (file->f_op->unlocked_ioctl) 94 return file->f_op->unlocked_ioctl(file, cmd, arg); 95 96 return -ENOTTY; 97} 98 99/* Handle 32-bit COMEDI_CHANINFO ioctl. */ 100static int compat_chaninfo(struct file *file, unsigned long arg) 101{ 102 struct comedi_chaninfo __user *chaninfo; 103 struct comedi32_chaninfo_struct __user *chaninfo32; 104 int err; 105 union { 106 unsigned int uint; 107 compat_uptr_t uptr; 108 } temp; 109 110 chaninfo32 = compat_ptr(arg); 111 chaninfo = compat_alloc_user_space(sizeof(*chaninfo)); 112 113 /* Copy chaninfo structure. Ignore unused members. */ 114 if (!access_ok(VERIFY_READ, chaninfo32, sizeof(*chaninfo32)) || 115 !access_ok(VERIFY_WRITE, chaninfo, sizeof(*chaninfo))) 116 return -EFAULT; 117 118 err = 0; 119 err |= __get_user(temp.uint, &chaninfo32->subdev); 120 err |= __put_user(temp.uint, &chaninfo->subdev); 121 err |= __get_user(temp.uptr, &chaninfo32->maxdata_list); 122 err |= __put_user(compat_ptr(temp.uptr), &chaninfo->maxdata_list); 123 err |= __get_user(temp.uptr, &chaninfo32->flaglist); 124 err |= __put_user(compat_ptr(temp.uptr), &chaninfo->flaglist); 125 err |= __get_user(temp.uptr, &chaninfo32->rangelist); 126 err |= __put_user(compat_ptr(temp.uptr), &chaninfo->rangelist); 127 if (err) 128 return -EFAULT; 129 130 return translated_ioctl(file, COMEDI_CHANINFO, (unsigned long)chaninfo); 131} 132 133/* Handle 32-bit COMEDI_RANGEINFO ioctl. */ 134static int compat_rangeinfo(struct file *file, unsigned long arg) 135{ 136 struct comedi_rangeinfo __user *rangeinfo; 137 struct comedi32_rangeinfo_struct __user *rangeinfo32; 138 int err; 139 union { 140 unsigned int uint; 141 compat_uptr_t uptr; 142 } temp; 143 144 rangeinfo32 = compat_ptr(arg); 145 rangeinfo = compat_alloc_user_space(sizeof(*rangeinfo)); 146 147 /* Copy rangeinfo structure. */ 148 if (!access_ok(VERIFY_READ, rangeinfo32, sizeof(*rangeinfo32)) || 149 !access_ok(VERIFY_WRITE, rangeinfo, sizeof(*rangeinfo))) 150 return -EFAULT; 151 152 err = 0; 153 err |= __get_user(temp.uint, &rangeinfo32->range_type); 154 err |= __put_user(temp.uint, &rangeinfo->range_type); 155 err |= __get_user(temp.uptr, &rangeinfo32->range_ptr); 156 err |= __put_user(compat_ptr(temp.uptr), &rangeinfo->range_ptr); 157 if (err) 158 return -EFAULT; 159 160 return translated_ioctl(file, COMEDI_RANGEINFO, 161 (unsigned long)rangeinfo); 162} 163 164/* Copy 32-bit cmd structure to native cmd structure. */ 165static int get_compat_cmd(struct comedi_cmd __user *cmd, 166 struct comedi32_cmd_struct __user *cmd32) 167{ 168 int err; 169 union { 170 unsigned int uint; 171 compat_uptr_t uptr; 172 } temp; 173 174 /* Copy cmd structure. */ 175 if (!access_ok(VERIFY_READ, cmd32, sizeof(*cmd32)) || 176 !access_ok(VERIFY_WRITE, cmd, sizeof(*cmd))) 177 return -EFAULT; 178 179 err = 0; 180 err |= __get_user(temp.uint, &cmd32->subdev); 181 err |= __put_user(temp.uint, &cmd->subdev); 182 err |= __get_user(temp.uint, &cmd32->flags); 183 err |= __put_user(temp.uint, &cmd->flags); 184 err |= __get_user(temp.uint, &cmd32->start_src); 185 err |= __put_user(temp.uint, &cmd->start_src); 186 err |= __get_user(temp.uint, &cmd32->start_arg); 187 err |= __put_user(temp.uint, &cmd->start_arg); 188 err |= __get_user(temp.uint, &cmd32->scan_begin_src); 189 err |= __put_user(temp.uint, &cmd->scan_begin_src); 190 err |= __get_user(temp.uint, &cmd32->scan_begin_arg); 191 err |= __put_user(temp.uint, &cmd->scan_begin_arg); 192 err |= __get_user(temp.uint, &cmd32->convert_src); 193 err |= __put_user(temp.uint, &cmd->convert_src); 194 err |= __get_user(temp.uint, &cmd32->convert_arg); 195 err |= __put_user(temp.uint, &cmd->convert_arg); 196 err |= __get_user(temp.uint, &cmd32->scan_end_src); 197 err |= __put_user(temp.uint, &cmd->scan_end_src); 198 err |= __get_user(temp.uint, &cmd32->scan_end_arg); 199 err |= __put_user(temp.uint, &cmd->scan_end_arg); 200 err |= __get_user(temp.uint, &cmd32->stop_src); 201 err |= __put_user(temp.uint, &cmd->stop_src); 202 err |= __get_user(temp.uint, &cmd32->stop_arg); 203 err |= __put_user(temp.uint, &cmd->stop_arg); 204 err |= __get_user(temp.uptr, &cmd32->chanlist); 205 err |= __put_user(compat_ptr(temp.uptr), &cmd->chanlist); 206 err |= __get_user(temp.uint, &cmd32->chanlist_len); 207 err |= __put_user(temp.uint, &cmd->chanlist_len); 208 err |= __get_user(temp.uptr, &cmd32->data); 209 err |= __put_user(compat_ptr(temp.uptr), &cmd->data); 210 err |= __get_user(temp.uint, &cmd32->data_len); 211 err |= __put_user(temp.uint, &cmd->data_len); 212 return err ? -EFAULT : 0; 213} 214 215/* Copy native cmd structure to 32-bit cmd structure. */ 216static int put_compat_cmd(struct comedi32_cmd_struct __user *cmd32, 217 struct comedi_cmd __user *cmd) 218{ 219 int err; 220 unsigned int temp; 221 222 /* 223 * Copy back most of cmd structure. 224 * 225 * Assume the pointer values are already valid. 226 * (Could use ptr_to_compat() to set them.) 227 */ 228 if (!access_ok(VERIFY_READ, cmd, sizeof(*cmd)) || 229 !access_ok(VERIFY_WRITE, cmd32, sizeof(*cmd32))) 230 return -EFAULT; 231 232 err = 0; 233 err |= __get_user(temp, &cmd->subdev); 234 err |= __put_user(temp, &cmd32->subdev); 235 err |= __get_user(temp, &cmd->flags); 236 err |= __put_user(temp, &cmd32->flags); 237 err |= __get_user(temp, &cmd->start_src); 238 err |= __put_user(temp, &cmd32->start_src); 239 err |= __get_user(temp, &cmd->start_arg); 240 err |= __put_user(temp, &cmd32->start_arg); 241 err |= __get_user(temp, &cmd->scan_begin_src); 242 err |= __put_user(temp, &cmd32->scan_begin_src); 243 err |= __get_user(temp, &cmd->scan_begin_arg); 244 err |= __put_user(temp, &cmd32->scan_begin_arg); 245 err |= __get_user(temp, &cmd->convert_src); 246 err |= __put_user(temp, &cmd32->convert_src); 247 err |= __get_user(temp, &cmd->convert_arg); 248 err |= __put_user(temp, &cmd32->convert_arg); 249 err |= __get_user(temp, &cmd->scan_end_src); 250 err |= __put_user(temp, &cmd32->scan_end_src); 251 err |= __get_user(temp, &cmd->scan_end_arg); 252 err |= __put_user(temp, &cmd32->scan_end_arg); 253 err |= __get_user(temp, &cmd->stop_src); 254 err |= __put_user(temp, &cmd32->stop_src); 255 err |= __get_user(temp, &cmd->stop_arg); 256 err |= __put_user(temp, &cmd32->stop_arg); 257 /* Assume chanlist pointer is unchanged. */ 258 err |= __get_user(temp, &cmd->chanlist_len); 259 err |= __put_user(temp, &cmd32->chanlist_len); 260 /* Assume data pointer is unchanged. */ 261 err |= __get_user(temp, &cmd->data_len); 262 err |= __put_user(temp, &cmd32->data_len); 263 return err ? -EFAULT : 0; 264} 265 266/* Handle 32-bit COMEDI_CMD ioctl. */ 267static int compat_cmd(struct file *file, unsigned long arg) 268{ 269 struct comedi_cmd __user *cmd; 270 struct comedi32_cmd_struct __user *cmd32; 271 int rc, err; 272 273 cmd32 = compat_ptr(arg); 274 cmd = compat_alloc_user_space(sizeof(*cmd)); 275 276 rc = get_compat_cmd(cmd, cmd32); 277 if (rc) 278 return rc; 279 280 rc = translated_ioctl(file, COMEDI_CMD, (unsigned long)cmd); 281 if (rc == -EAGAIN) { 282 /* Special case: copy cmd back to user. */ 283 err = put_compat_cmd(cmd32, cmd); 284 if (err) 285 rc = err; 286 } 287 288 return rc; 289} 290 291/* Handle 32-bit COMEDI_CMDTEST ioctl. */ 292static int compat_cmdtest(struct file *file, unsigned long arg) 293{ 294 struct comedi_cmd __user *cmd; 295 struct comedi32_cmd_struct __user *cmd32; 296 int rc, err; 297 298 cmd32 = compat_ptr(arg); 299 cmd = compat_alloc_user_space(sizeof(*cmd)); 300 301 rc = get_compat_cmd(cmd, cmd32); 302 if (rc) 303 return rc; 304 305 rc = translated_ioctl(file, COMEDI_CMDTEST, (unsigned long)cmd); 306 if (rc < 0) 307 return rc; 308 309 err = put_compat_cmd(cmd32, cmd); 310 if (err) 311 rc = err; 312 313 return rc; 314} 315 316/* Copy 32-bit insn structure to native insn structure. */ 317static int get_compat_insn(struct comedi_insn __user *insn, 318 struct comedi32_insn_struct __user *insn32) 319{ 320 int err; 321 union { 322 unsigned int uint; 323 compat_uptr_t uptr; 324 } temp; 325 326 /* Copy insn structure. Ignore the unused members. */ 327 err = 0; 328 if (!access_ok(VERIFY_READ, insn32, sizeof(*insn32)) || 329 !access_ok(VERIFY_WRITE, insn, sizeof(*insn))) 330 return -EFAULT; 331 332 err |= __get_user(temp.uint, &insn32->insn); 333 err |= __put_user(temp.uint, &insn->insn); 334 err |= __get_user(temp.uint, &insn32->n); 335 err |= __put_user(temp.uint, &insn->n); 336 err |= __get_user(temp.uptr, &insn32->data); 337 err |= __put_user(compat_ptr(temp.uptr), &insn->data); 338 err |= __get_user(temp.uint, &insn32->subdev); 339 err |= __put_user(temp.uint, &insn->subdev); 340 err |= __get_user(temp.uint, &insn32->chanspec); 341 err |= __put_user(temp.uint, &insn->chanspec); 342 return err ? -EFAULT : 0; 343} 344 345/* Handle 32-bit COMEDI_INSNLIST ioctl. */ 346static int compat_insnlist(struct file *file, unsigned long arg) 347{ 348 struct combined_insnlist { 349 struct comedi_insnlist insnlist; 350 struct comedi_insn insn[1]; 351 } __user *s; 352 struct comedi32_insnlist_struct __user *insnlist32; 353 struct comedi32_insn_struct __user *insn32; 354 compat_uptr_t uptr; 355 unsigned int n_insns, n; 356 int err, rc; 357 358 insnlist32 = compat_ptr(arg); 359 360 /* Get 32-bit insnlist structure. */ 361 if (!access_ok(VERIFY_READ, insnlist32, sizeof(*insnlist32))) 362 return -EFAULT; 363 364 err = 0; 365 err |= __get_user(n_insns, &insnlist32->n_insns); 366 err |= __get_user(uptr, &insnlist32->insns); 367 insn32 = compat_ptr(uptr); 368 if (err) 369 return -EFAULT; 370 371 /* Allocate user memory to copy insnlist and insns into. */ 372 s = compat_alloc_user_space(offsetof(struct combined_insnlist, 373 insn[n_insns])); 374 375 /* Set native insnlist structure. */ 376 if (!access_ok(VERIFY_WRITE, &s->insnlist, sizeof(s->insnlist))) 377 return -EFAULT; 378 379 err |= __put_user(n_insns, &s->insnlist.n_insns); 380 err |= __put_user(&s->insn[0], &s->insnlist.insns); 381 if (err) 382 return -EFAULT; 383 384 /* Copy insn structures. */ 385 for (n = 0; n < n_insns; n++) { 386 rc = get_compat_insn(&s->insn[n], &insn32[n]); 387 if (rc) 388 return rc; 389 } 390 391 return translated_ioctl(file, COMEDI_INSNLIST, 392 (unsigned long)&s->insnlist); 393} 394 395/* Handle 32-bit COMEDI_INSN ioctl. */ 396static int compat_insn(struct file *file, unsigned long arg) 397{ 398 struct comedi_insn __user *insn; 399 struct comedi32_insn_struct __user *insn32; 400 int rc; 401 402 insn32 = compat_ptr(arg); 403 insn = compat_alloc_user_space(sizeof(*insn)); 404 405 rc = get_compat_insn(insn, insn32); 406 if (rc) 407 return rc; 408 409 return translated_ioctl(file, COMEDI_INSN, (unsigned long)insn); 410} 411 412/* 413 * compat_ioctl file operation. 414 * 415 * Returns -ENOIOCTLCMD for unrecognised ioctl codes. 416 */ 417long comedi_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 418{ 419 int rc; 420 421 switch (cmd) { 422 case COMEDI_DEVCONFIG: 423 case COMEDI_DEVINFO: 424 case COMEDI_SUBDINFO: 425 case COMEDI_BUFCONFIG: 426 case COMEDI_BUFINFO: 427 /* Just need to translate the pointer argument. */ 428 arg = (unsigned long)compat_ptr(arg); 429 rc = translated_ioctl(file, cmd, arg); 430 break; 431 case COMEDI_LOCK: 432 case COMEDI_UNLOCK: 433 case COMEDI_CANCEL: 434 case COMEDI_POLL: 435 case COMEDI_SETRSUBD: 436 case COMEDI_SETWSUBD: 437 /* No translation needed. */ 438 rc = translated_ioctl(file, cmd, arg); 439 break; 440 case COMEDI32_CHANINFO: 441 rc = compat_chaninfo(file, arg); 442 break; 443 case COMEDI32_RANGEINFO: 444 rc = compat_rangeinfo(file, arg); 445 break; 446 case COMEDI32_CMD: 447 rc = compat_cmd(file, arg); 448 break; 449 case COMEDI32_CMDTEST: 450 rc = compat_cmdtest(file, arg); 451 break; 452 case COMEDI32_INSNLIST: 453 rc = compat_insnlist(file, arg); 454 break; 455 case COMEDI32_INSN: 456 rc = compat_insn(file, arg); 457 break; 458 default: 459 rc = -ENOIOCTLCMD; 460 break; 461 } 462 return rc; 463} 464