block/compat_ioctl.c

   1 #include <linux/blkdev.h>
   2 #include <linux/blkpg.h>
   3 #include <linux/blktrace_api.h>
   4 #include <linux/cdrom.h>
   5 #include <linux/compat.h>
   6 #include <linux/elevator.h>
   7 #include <linux/hdreg.h>
   8 #include <linux/slab.h>
   9 #include <linux/syscalls.h>
  10 #include <linux/types.h>
  11 #include <linux/uaccess.h>
  12
  13 static int compat_put_ushort(unsigned long arg, unsigned short val)
  14 {
  15         return put_user(val, (unsigned short __user *)compat_ptr(arg));
  16 }
  17
  18 static int compat_put_int(unsigned long arg, int val)
  19 {
  20         return put_user(val, (compat_int_t __user *)compat_ptr(arg));
  21 }
  22
  23 static int compat_put_uint(unsigned long arg, unsigned int val)
  24 {
  25         return put_user(val, (compat_uint_t __user *)compat_ptr(arg));
  26 }
  27
  28 static int compat_put_long(unsigned long arg, long val)
  29 {
  30         return put_user(val, (compat_long_t __user *)compat_ptr(arg));
  31 }
  32
  33 static int compat_put_ulong(unsigned long arg, compat_ulong_t val)
  34 {
  35         return put_user(val, (compat_ulong_t __user *)compat_ptr(arg));
  36 }
  37
  38 static int compat_put_u64(unsigned long arg, u64 val)
  39 {
  40         return put_user(val, (compat_u64 __user *)compat_ptr(arg));
  41 }
  42
  43 struct compat_hd_geometry {
  44         unsigned char heads;
  45         unsigned char sectors;
  46         unsigned short cylinders;
  47         u32 start;
  48 };
  49
  50 static int compat_hdio_getgeo(struct gendisk *disk, struct block_device *bdev,
  51                         struct compat_hd_geometry __user *ugeo)
  52 {
  53         struct hd_geometry geo;
  54         int ret;
  55
  56         if (!ugeo)
  57                 return -EINVAL;
  58         if (!disk->fops->getgeo)
  59                 return -ENOTTY;
  60
  61         memset(&geo, 0, sizeof(geo));
  62         /*
  63          * We need to set the startsect first, the driver may
  64          * want to override it.
  65          */
  66         geo.start = get_start_sect(bdev);
  67         ret = disk->fops->getgeo(bdev, &geo);
  68         if (ret)
  69                 return ret;
  70
  71         ret = copy_to_user(ugeo, &geo, 4);
  72         ret |= put_user(geo.start, &ugeo->start);
  73         if (ret)
  74                 ret = -EFAULT;
  75
  76         return ret;
  77 }
  78
  79 static int compat_hdio_ioctl(struct block_device *bdev, fmode_t mode,
  80                 unsigned int cmd, unsigned long arg)
  81 {
  82         unsigned long __user *p;
  83         int error;
  84
  85         p = compat_alloc_user_space(sizeof(unsigned long));
  86         error = __blkdev_driver_ioctl(bdev, mode,
  87                                 cmd, (unsigned long)p);
  88         if (error == 0) {
  89                 unsigned int __user *uvp = compat_ptr(arg);
  90                 unsigned long v;
  91                 if (get_user(v, p) || put_user(v, uvp))
  92                         error = -EFAULT;
  93         }
  94         return error;
  95 }
  96
  97 struct compat_cdrom_read_audio {
  98         union cdrom_addr        addr;
  99         u8                      addr_format;
 100         compat_int_t            nframes;
 101         compat_caddr_t          buf;
 102 };
 103
 104 struct compat_cdrom_generic_command {
 105         unsigned char   cmd[CDROM_PACKET_SIZE];
 106         compat_caddr_t  buffer;
 107         compat_uint_t   buflen;
 108         compat_int_t    stat;
 109         compat_caddr_t  sense;
 110         unsigned char   data_direction;
 111         compat_int_t    quiet;
 112         compat_int_t    timeout;
 113         compat_caddr_t  reserved[1];
 114 };
 115
 116 static int compat_cdrom_read_audio(struct block_device *bdev, fmode_t mode,
 117                 unsigned int cmd, unsigned long arg)
 118 {
 119         struct cdrom_read_audio __user *cdread_audio;
 120         struct compat_cdrom_read_audio __user *cdread_audio32;
 121         __u32 data;
 122         void __user *datap;
 123
 124         cdread_audio = compat_alloc_user_space(sizeof(*cdread_audio));
 125         cdread_audio32 = compat_ptr(arg);
 126
 127         if (copy_in_user(&cdread_audio->addr,
 128                          &cdread_audio32->addr,
 129                          (sizeof(*cdread_audio32) -
 130                           sizeof(compat_caddr_t))))
 131                 return -EFAULT;
 132
 133         if (get_user(data, &cdread_audio32->buf))
 134                 return -EFAULT;
 135         datap = compat_ptr(data);
 136         if (put_user(datap, &cdread_audio->buf))
 137                 return -EFAULT;
 138
 139         return __blkdev_driver_ioctl(bdev, mode, cmd,
 140                         (unsigned long)cdread_audio);
 141 }
 142
 143 static int compat_cdrom_generic_command(struct block_device *bdev, fmode_t mode,
 144                 unsigned int cmd, unsigned long arg)
 145 {
 146         struct cdrom_generic_command __user *cgc;
 147         struct compat_cdrom_generic_command __user *cgc32;
 148         u32 data;
 149         unsigned char dir;
 150         int itmp;
 151
 152         cgc = compat_alloc_user_space(sizeof(*cgc));
 153         cgc32 = compat_ptr(arg);
 154
 155         if (copy_in_user(&cgc->cmd, &cgc32->cmd, sizeof(cgc->cmd)) ||
 156             get_user(data, &cgc32->buffer) ||
 157             put_user(compat_ptr(data), &cgc->buffer) ||
 158             copy_in_user(&cgc->buflen, &cgc32->buflen,
 159                          (sizeof(unsigned int) + sizeof(int))) ||
 160             get_user(data, &cgc32->sense) ||
 161             put_user(compat_ptr(data), &cgc->sense) ||
 162             get_user(dir, &cgc32->data_direction) ||
 163             put_user(dir, &cgc->data_direction) ||
 164             get_user(itmp, &cgc32->quiet) ||
 165             put_user(itmp, &cgc->quiet) ||
 166             get_user(itmp, &cgc32->timeout) ||
 167             put_user(itmp, &cgc->timeout) ||
 168             get_user(data, &cgc32->reserved[0]) ||
 169             put_user(compat_ptr(data), &cgc->reserved[0]))
 170                 return -EFAULT;
 171
 172         return __blkdev_driver_ioctl(bdev, mode, cmd, (unsigned long)cgc);
 173 }
 174
 175 struct compat_blkpg_ioctl_arg {
 176         compat_int_t op;
 177         compat_int_t flags;
 178         compat_int_t datalen;
 179         compat_caddr_t data;
 180 };
 181
 182 static int compat_blkpg_ioctl(struct block_device *bdev, fmode_t mode,
 183                 unsigned int cmd, struct compat_blkpg_ioctl_arg __user *ua32)
 184 {
 185         struct blkpg_ioctl_arg __user *a = compat_alloc_user_space(sizeof(*a));
 186         compat_caddr_t udata;
 187         compat_int_t n;
 188         int err;
 189
 190         err = get_user(n, &ua32->op);
 191         err |= put_user(n, &a->op);
 192         err |= get_user(n, &ua32->flags);
 193         err |= put_user(n, &a->flags);
 194         err |= get_user(n, &ua32->datalen);
 195         err |= put_user(n, &a->datalen);
 196         err |= get_user(udata, &ua32->data);
 197         err |= put_user(compat_ptr(udata), &a->data);
 198         if (err)
 199                 return err;
 200
 201         return blkdev_ioctl(bdev, mode, cmd, (unsigned long)a);
 202 }
 203
 204 #define BLKBSZGET_32            _IOR(0x12, 112, int)
 205 #define BLKBSZSET_32            _IOW(0x12, 113, int)
 206 #define BLKGETSIZE64_32         _IOR(0x12, 114, int)
 207
 208 static int compat_blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
 209                         unsigned cmd, unsigned long arg)
 210 {
 211         switch (cmd) {
 212         case HDIO_GET_UNMASKINTR:
 213         case HDIO_GET_MULTCOUNT:
 214         case HDIO_GET_KEEPSETTINGS:
 215         case HDIO_GET_32BIT:
 216         case HDIO_GET_NOWERR:
 217         case HDIO_GET_DMA:
 218         case HDIO_GET_NICE:
 219         case HDIO_GET_WCACHE:
 220         case HDIO_GET_ACOUSTIC:
 221         case HDIO_GET_ADDRESS:
 222         case HDIO_GET_BUSSTATE:
 223                 return compat_hdio_ioctl(bdev, mode, cmd, arg);
 224         case CDROMREADAUDIO:
 225                 return compat_cdrom_read_audio(bdev, mode, cmd, arg);
 226         case CDROM_SEND_PACKET:
 227                 return compat_cdrom_generic_command(bdev, mode, cmd, arg);
 228
 229         /*
 230          * No handler required for the ones below, we just need to
 231          * convert arg to a 64 bit pointer.
 232          */
 233         case BLKSECTSET:
 234         /*
 235          * 0x03 -- HD/IDE ioctl's used by hdparm and friends.
 236          *         Some need translations, these do not.
 237          */
 238         case HDIO_GET_IDENTITY:
 239         case HDIO_DRIVE_TASK:
 240         case HDIO_DRIVE_CMD:
 241         /* 0x330 is reserved -- it used to be HDIO_GETGEO_BIG */
 242         case 0x330:
 243         /* CDROM stuff */
 244         case CDROMPAUSE:
 245         case CDROMRESUME:
 246         case CDROMPLAYMSF:
 247         case CDROMPLAYTRKIND:
 248         case CDROMREADTOCHDR:
 249         case CDROMREADTOCENTRY:
 250         case CDROMSTOP:
 251         case CDROMSTART:
 252         case CDROMEJECT:
 253         case CDROMVOLCTRL:
 254         case CDROMSUBCHNL:
 255         case CDROMMULTISESSION:
 256         case CDROM_GET_MCN:
 257         case CDROMRESET:
 258         case CDROMVOLREAD:
 259         case CDROMSEEK:
 260         case CDROMPLAYBLK:
 261         case CDROMCLOSETRAY:
 262         case CDROM_DISC_STATUS:
 263         case CDROM_CHANGER_NSLOTS:
 264         case CDROM_GET_CAPABILITY:
 265         /* Ignore cdrom.h about these next 5 ioctls, they absolutely do
 266          * not take a struct cdrom_read, instead they take a struct cdrom_msf
 267          * which is compatible.
 268          */
 269         case CDROMREADMODE2:
 270         case CDROMREADMODE1:
 271         case CDROMREADRAW:
 272         case CDROMREADCOOKED:
 273         case CDROMREADALL:
 274         /* DVD ioctls */
 275         case DVD_READ_STRUCT:
 276         case DVD_WRITE_STRUCT:
 277         case DVD_AUTH:
 278                 arg = (unsigned long)compat_ptr(arg);
 279         /* These intepret arg as an unsigned long, not as a pointer,
 280          * so we must not do compat_ptr() conversion. */
 281         case HDIO_SET_MULTCOUNT:
 282         case HDIO_SET_UNMASKINTR:
 283         case HDIO_SET_KEEPSETTINGS:
 284         case HDIO_SET_32BIT:
 285         case HDIO_SET_NOWERR:
 286         case HDIO_SET_DMA:
 287         case HDIO_SET_PIO_MODE:
 288         case HDIO_SET_NICE:
 289         case HDIO_SET_WCACHE:
 290         case HDIO_SET_ACOUSTIC:
 291         case HDIO_SET_BUSSTATE:
 292         case HDIO_SET_ADDRESS:
 293         case CDROMEJECT_SW:
 294         case CDROM_SET_OPTIONS:
 295         case CDROM_CLEAR_OPTIONS:
 296         case CDROM_SELECT_SPEED:
 297         case CDROM_SELECT_DISC:
 298         case CDROM_MEDIA_CHANGED:
 299         case CDROM_DRIVE_STATUS:
 300         case CDROM_LOCKDOOR:
 301         case CDROM_DEBUG:
 302                 break;
 303         default:
 304                 /* unknown ioctl number */
 305                 return -ENOIOCTLCMD;
 306         }
 307
 308         return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
 309 }
 310
 311 /* Most of the generic ioctls are handled in the normal fallback path.
 312    This assumes the blkdev's low level compat_ioctl always returns
 313    ENOIOCTLCMD for unknown ioctls. */
 314 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 315 {
 316         int ret = -ENOIOCTLCMD;
 317         struct inode *inode = file->f_mapping->host;
 318         struct block_device *bdev = inode->i_bdev;
 319         struct gendisk *disk = bdev->bd_disk;
 320         fmode_t mode = file->f_mode;
 321         loff_t size;
 322         unsigned int max_sectors;
 323
 324         /*
 325          * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
 326          * to updated it before every ioctl.
 327          */
 328         if (file->f_flags & O_NDELAY)
 329                 mode |= FMODE_NDELAY;
 330         else
 331                 mode &= ~FMODE_NDELAY;
 332
 333         switch (cmd) {
 334         case HDIO_GETGEO:
 335                 return compat_hdio_getgeo(disk, bdev, compat_ptr(arg));
 336         case BLKPBSZGET:
 337                 return compat_put_uint(arg, bdev_physical_block_size(bdev));
 338         case BLKIOMIN:
 339                 return compat_put_uint(arg, bdev_io_min(bdev));
 340         case BLKIOOPT:
 341                 return compat_put_uint(arg, bdev_io_opt(bdev));
 342         case BLKALIGNOFF:
 343                 return compat_put_int(arg, bdev_alignment_offset(bdev));
 344         case BLKDISCARDZEROES:
 345                 return compat_put_uint(arg, 0);
 346         case BLKFLSBUF:
 347         case BLKROSET:
 348         case BLKDISCARD:
 349         case BLKSECDISCARD:
 350         case BLKZEROOUT:
 351         /*
 352          * the ones below are implemented in blkdev_locked_ioctl,
 353          * but we call blkdev_ioctl, which gets the lock for us
 354          */
 355         case BLKRRPART:
 356                 return blkdev_ioctl(bdev, mode, cmd,
 357                                 (unsigned long)compat_ptr(arg));
 358         case BLKBSZSET_32:
 359                 return blkdev_ioctl(bdev, mode, BLKBSZSET,
 360                                 (unsigned long)compat_ptr(arg));
 361         case BLKPG:
 362                 return compat_blkpg_ioctl(bdev, mode, cmd, compat_ptr(arg));
 363         case BLKRAGET:
 364         case BLKFRAGET:
 365                 if (!arg)
 366                         return -EINVAL;
 367                 return compat_put_long(arg,
 368                                (bdev->bd_bdi->ra_pages * PAGE_SIZE) / 512);
 369         case BLKROGET: /* compatible */
 370                 return compat_put_int(arg, bdev_read_only(bdev) != 0);
 371         case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
 372                 return compat_put_int(arg, block_size(bdev));
 373         case BLKSSZGET: /* get block device hardware sector size */
 374                 return compat_put_int(arg, bdev_logical_block_size(bdev));
 375         case BLKSECTGET:
 376                 max_sectors = min_t(unsigned int, USHRT_MAX,
 377                                     queue_max_sectors(bdev_get_queue(bdev)));
 378                 return compat_put_ushort(arg, max_sectors);
 379         case BLKROTATIONAL:
 380                 return compat_put_ushort(arg,
 381                                          !blk_queue_nonrot(bdev_get_queue(bdev)));
 382         case BLKRASET: /* compatible, but no compat_ptr (!) */
 383         case BLKFRASET:
 384                 if (!capable(CAP_SYS_ADMIN))
 385                         return -EACCES;
 386                 bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
 387                 return 0;
 388         case BLKGETSIZE:
 389                 size = i_size_read(bdev->bd_inode);
 390                 if ((size >> 9) > ~0UL)
 391                         return -EFBIG;
 392                 return compat_put_ulong(arg, size >> 9);
 393
 394         case BLKGETSIZE64_32:
 395                 return compat_put_u64(arg, i_size_read(bdev->bd_inode));
 396
 397         case BLKTRACESETUP32:
 398         case BLKTRACESTART: /* compatible */
 399         case BLKTRACESTOP:  /* compatible */
 400         case BLKTRACETEARDOWN: /* compatible */
 401                 ret = blk_trace_ioctl(bdev, cmd, compat_ptr(arg));
 402                 return ret;
 403         default:
 404                 if (disk->fops->compat_ioctl)
 405                         ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
 406                 if (ret == -ENOIOCTLCMD)
 407                         ret = compat_blkdev_driver_ioctl(bdev, mode, cmd, arg);
 408                 return ret;
 409         }
 410 }