LXR linux/block/compat

   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
  13static int compat_put_ushort(unsigned long arg, unsigned short val)
  14{
  15        return put_user(val, (unsigned short __user *)compat_ptr(arg));
  16}
  17
  18static int compat_put_int(unsigned long arg, int val)
  19{
  20        return put_user(val, (compat_int_t __user *)compat_ptr(arg));
  21}
  22
  23static 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
  28static int compat_put_long(unsigned long arg, long val)
  29{
  30        return put_user(val, (compat_long_t __user *)compat_ptr(arg));
  31}
  32
  33static 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
  38static int compat_put_u64(unsigned long arg, u64 val)
  39{
  40        return put_user(val, (compat_u64 __user *)compat_ptr(arg));
  41}
  42
  43struct compat_hd_geometry {
  44        unsigned char heads;
  45        unsigned char sectors;
  46        unsigned short cylinders;
  47        u32 start;
  48};
  49
  50static 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
  79static 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
  97struct 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
 104struct 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
 116static 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
 143static 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
 175struct 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
 182static 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
 208static 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. */
 314long 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}
 411