diff options
Diffstat (limited to 'block/ioctl.c')
| -rw-r--r-- | block/ioctl.c | 707 |
1 files changed, 707 insertions, 0 deletions
diff --git a/block/ioctl.c b/block/ioctl.c new file mode 100644 index 000000000..e7eed7dad --- /dev/null +++ b/block/ioctl.c @@ -0,0 +1,707 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/capability.h> +#include <linux/compat.h> +#include <linux/blkdev.h> +#include <linux/export.h> +#include <linux/gfp.h> +#include <linux/blkpg.h> +#include <linux/hdreg.h> +#include <linux/backing-dev.h> +#include <linux/fs.h> +#include <linux/blktrace_api.h> +#include <linux/pr.h> +#include <linux/uaccess.h> +#include "blk.h" + +static int blkpg_do_ioctl(struct block_device *bdev, + struct blkpg_partition __user *upart, int op) +{ + struct blkpg_partition p; + long long start, length; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + if (copy_from_user(&p, upart, sizeof(struct blkpg_partition))) + return -EFAULT; + if (bdev_is_partition(bdev)) + return -EINVAL; + + if (p.pno <= 0) + return -EINVAL; + + if (op == BLKPG_DEL_PARTITION) + return bdev_del_partition(bdev, p.pno); + + start = p.start >> SECTOR_SHIFT; + length = p.length >> SECTOR_SHIFT; + + /* check for fit in a hd_struct */ + if (sizeof(sector_t) < sizeof(long long)) { + long pstart = start, plength = length; + + if (pstart != start || plength != length || pstart < 0 || + plength < 0 || p.pno > 65535) + return -EINVAL; + } + + switch (op) { + case BLKPG_ADD_PARTITION: + /* check if partition is aligned to blocksize */ + if (p.start & (bdev_logical_block_size(bdev) - 1)) + return -EINVAL; + return bdev_add_partition(bdev, p.pno, start, length); + case BLKPG_RESIZE_PARTITION: + return bdev_resize_partition(bdev, p.pno, start, length); + default: + return -EINVAL; + } +} + +static int blkpg_ioctl(struct block_device *bdev, + struct blkpg_ioctl_arg __user *arg) +{ + struct blkpg_partition __user *udata; + int op; + + if (get_user(op, &arg->op) || get_user(udata, &arg->data)) + return -EFAULT; + + return blkpg_do_ioctl(bdev, udata, op); +} + +#ifdef CONFIG_COMPAT +struct compat_blkpg_ioctl_arg { + compat_int_t op; + compat_int_t flags; + compat_int_t datalen; + compat_caddr_t data; +}; + +static int compat_blkpg_ioctl(struct block_device *bdev, + struct compat_blkpg_ioctl_arg __user *arg) +{ + compat_caddr_t udata; + int op; + + if (get_user(op, &arg->op) || get_user(udata, &arg->data)) + return -EFAULT; + + return blkpg_do_ioctl(bdev, compat_ptr(udata), op); +} +#endif + +static int blkdev_reread_part(struct block_device *bdev, fmode_t mode) +{ + struct block_device *tmp; + + if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev)) + return -EINVAL; + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + if (bdev->bd_part_count) + return -EBUSY; + + /* + * Reopen the device to revalidate the driver state and force a + * partition rescan. + */ + mode &= ~FMODE_EXCL; + set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state); + + tmp = blkdev_get_by_dev(bdev->bd_dev, mode, NULL); + if (IS_ERR(tmp)) + return PTR_ERR(tmp); + blkdev_put(tmp, mode); + return 0; +} + +static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, + unsigned long arg, unsigned long flags) +{ + uint64_t range[2]; + uint64_t start, len; + struct request_queue *q = bdev_get_queue(bdev); + int err; + + if (!(mode & FMODE_WRITE)) + return -EBADF; + + if (!blk_queue_discard(q)) + return -EOPNOTSUPP; + + if (copy_from_user(range, (void __user *)arg, sizeof(range))) + return -EFAULT; + + start = range[0]; + len = range[1]; + + if (start & 511) + return -EINVAL; + if (len & 511) + return -EINVAL; + + if (start + len > i_size_read(bdev->bd_inode)) + return -EINVAL; + + err = truncate_bdev_range(bdev, mode, start, start + len - 1); + if (err) + return err; + + return blkdev_issue_discard(bdev, start >> 9, len >> 9, + GFP_KERNEL, flags); +} + +static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, + unsigned long arg) +{ + uint64_t range[2]; + uint64_t start, end, len; + int err; + + if (!(mode & FMODE_WRITE)) + return -EBADF; + + if (copy_from_user(range, (void __user *)arg, sizeof(range))) + return -EFAULT; + + start = range[0]; + len = range[1]; + end = start + len - 1; + + if (start & 511) + return -EINVAL; + if (len & 511) + return -EINVAL; + if (end >= (uint64_t)i_size_read(bdev->bd_inode)) + return -EINVAL; + if (end < start) + return -EINVAL; + + /* Invalidate the page cache, including dirty pages */ + err = truncate_bdev_range(bdev, mode, start, end); + if (err) + return err; + + return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, + BLKDEV_ZERO_NOUNMAP); +} + +static int put_ushort(unsigned short __user *argp, unsigned short val) +{ + return put_user(val, argp); +} + +static int put_int(int __user *argp, int val) +{ + return put_user(val, argp); +} + +static int put_uint(unsigned int __user *argp, unsigned int val) +{ + return put_user(val, argp); +} + +static int put_long(long __user *argp, long val) +{ + return put_user(val, argp); +} + +static int put_ulong(unsigned long __user *argp, unsigned long val) +{ + return put_user(val, argp); +} + +static int put_u64(u64 __user *argp, u64 val) +{ + return put_user(val, argp); +} + +#ifdef CONFIG_COMPAT +static int compat_put_long(compat_long_t __user *argp, long val) +{ + return put_user(val, argp); +} + +static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val) +{ + return put_user(val, argp); +} +#endif + +int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, + unsigned cmd, unsigned long arg) +{ + struct gendisk *disk = bdev->bd_disk; + + if (disk->fops->ioctl) + return disk->fops->ioctl(bdev, mode, cmd, arg); + + return -ENOTTY; +} +/* + * For the record: _GPL here is only because somebody decided to slap it + * on the previous export. Sheer idiocy, since it wasn't copyrightable + * at all and could be open-coded without any exports by anybody who cares. + */ +EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); + +#ifdef CONFIG_COMPAT +/* + * This is the equivalent of compat_ptr_ioctl(), to be used by block + * drivers that implement only commands that are completely compatible + * between 32-bit and 64-bit user space + */ +int blkdev_compat_ptr_ioctl(struct block_device *bdev, fmode_t mode, + unsigned cmd, unsigned long arg) +{ + struct gendisk *disk = bdev->bd_disk; + + if (disk->fops->ioctl) + return disk->fops->ioctl(bdev, mode, cmd, + (unsigned long)compat_ptr(arg)); + + return -ENOIOCTLCMD; +} +EXPORT_SYMBOL(blkdev_compat_ptr_ioctl); +#endif + +static int blkdev_pr_register(struct block_device *bdev, + struct pr_registration __user *arg) +{ + const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; + struct pr_registration reg; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (!ops || !ops->pr_register) + return -EOPNOTSUPP; + if (copy_from_user(®, arg, sizeof(reg))) + return -EFAULT; + + if (reg.flags & ~PR_FL_IGNORE_KEY) + return -EOPNOTSUPP; + return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags); +} + +static int blkdev_pr_reserve(struct block_device *bdev, + struct pr_reservation __user *arg) +{ + const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; + struct pr_reservation rsv; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (!ops || !ops->pr_reserve) + return -EOPNOTSUPP; + if (copy_from_user(&rsv, arg, sizeof(rsv))) + return -EFAULT; + + if (rsv.flags & ~PR_FL_IGNORE_KEY) + return -EOPNOTSUPP; + return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags); +} + +static int blkdev_pr_release(struct block_device *bdev, + struct pr_reservation __user *arg) +{ + const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; + struct pr_reservation rsv; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (!ops || !ops->pr_release) + return -EOPNOTSUPP; + if (copy_from_user(&rsv, arg, sizeof(rsv))) + return -EFAULT; + + if (rsv.flags) + return -EOPNOTSUPP; + return ops->pr_release(bdev, rsv.key, rsv.type); +} + +static int blkdev_pr_preempt(struct block_device *bdev, + struct pr_preempt __user *arg, bool abort) +{ + const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; + struct pr_preempt p; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (!ops || !ops->pr_preempt) + return -EOPNOTSUPP; + if (copy_from_user(&p, arg, sizeof(p))) + return -EFAULT; + + if (p.flags) + return -EOPNOTSUPP; + return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort); +} + +static int blkdev_pr_clear(struct block_device *bdev, + struct pr_clear __user *arg) +{ + const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; + struct pr_clear c; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (!ops || !ops->pr_clear) + return -EOPNOTSUPP; + if (copy_from_user(&c, arg, sizeof(c))) + return -EFAULT; + + if (c.flags) + return -EOPNOTSUPP; + return ops->pr_clear(bdev, c.key); +} + +/* + * Is it an unrecognized ioctl? The correct returns are either + * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a + * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl + * code before returning. + * + * Confused drivers sometimes return EINVAL, which is wrong. It + * means "I understood the ioctl command, but the parameters to + * it were wrong". + * + * We should aim to just fix the broken drivers, the EINVAL case + * should go away. + */ +static inline int is_unrecognized_ioctl(int ret) +{ + return ret == -EINVAL || + ret == -ENOTTY || + ret == -ENOIOCTLCMD; +} + +static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode, + unsigned cmd, unsigned long arg) +{ + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); + if (!is_unrecognized_ioctl(ret)) + return ret; + + fsync_bdev(bdev); + invalidate_bdev(bdev); + return 0; +} + +static int blkdev_roset(struct block_device *bdev, fmode_t mode, + unsigned cmd, unsigned long arg) +{ + int ret, n; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); + if (!is_unrecognized_ioctl(ret)) + return ret; + if (get_user(n, (int __user *)arg)) + return -EFAULT; + set_device_ro(bdev, n); + return 0; +} + +static int blkdev_getgeo(struct block_device *bdev, + struct hd_geometry __user *argp) +{ + struct gendisk *disk = bdev->bd_disk; + struct hd_geometry geo; + int ret; + + if (!argp) + return -EINVAL; + if (!disk->fops->getgeo) + return -ENOTTY; + + /* + * We need to set the startsect first, the driver may + * want to override it. + */ + memset(&geo, 0, sizeof(geo)); + geo.start = get_start_sect(bdev); + ret = disk->fops->getgeo(bdev, &geo); + if (ret) + return ret; + if (copy_to_user(argp, &geo, sizeof(geo))) + return -EFAULT; + return 0; +} + +#ifdef CONFIG_COMPAT +struct compat_hd_geometry { + unsigned char heads; + unsigned char sectors; + unsigned short cylinders; + u32 start; +}; + +static int compat_hdio_getgeo(struct block_device *bdev, + struct compat_hd_geometry __user *ugeo) +{ + struct gendisk *disk = bdev->bd_disk; + struct hd_geometry geo; + int ret; + + if (!ugeo) + return -EINVAL; + if (!disk->fops->getgeo) + return -ENOTTY; + + memset(&geo, 0, sizeof(geo)); + /* + * We need to set the startsect first, the driver may + * want to override it. + */ + geo.start = get_start_sect(bdev); + ret = disk->fops->getgeo(bdev, &geo); + if (ret) + return ret; + + ret = copy_to_user(ugeo, &geo, 4); + ret |= put_user(geo.start, &ugeo->start); + if (ret) + ret = -EFAULT; + + return ret; +} +#endif + +/* set the logical block size */ +static int blkdev_bszset(struct block_device *bdev, fmode_t mode, + int __user *argp) +{ + int ret, n; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + if (!argp) + return -EINVAL; + if (get_user(n, argp)) + return -EFAULT; + + if (mode & FMODE_EXCL) + return set_blocksize(bdev, n); + + if (IS_ERR(blkdev_get_by_dev(bdev->bd_dev, mode | FMODE_EXCL, &bdev))) + return -EBUSY; + ret = set_blocksize(bdev, n); + blkdev_put(bdev, mode | FMODE_EXCL); + + return ret; +} + +/* + * Common commands that are handled the same way on native and compat + * user space. Note the separate arg/argp parameters that are needed + * to deal with the compat_ptr() conversion. + */ +static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode, + unsigned cmd, unsigned long arg, void __user *argp) +{ + unsigned int max_sectors; + + switch (cmd) { + case BLKFLSBUF: + return blkdev_flushbuf(bdev, mode, cmd, arg); + case BLKROSET: + return blkdev_roset(bdev, mode, cmd, arg); + case BLKDISCARD: + return blk_ioctl_discard(bdev, mode, arg, 0); + case BLKSECDISCARD: + return blk_ioctl_discard(bdev, mode, arg, + BLKDEV_DISCARD_SECURE); + case BLKZEROOUT: + return blk_ioctl_zeroout(bdev, mode, arg); + case BLKREPORTZONE: + return blkdev_report_zones_ioctl(bdev, mode, cmd, arg); + case BLKRESETZONE: + case BLKOPENZONE: + case BLKCLOSEZONE: + case BLKFINISHZONE: + return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg); + case BLKGETZONESZ: + return put_uint(argp, bdev_zone_sectors(bdev)); + case BLKGETNRZONES: + return put_uint(argp, blkdev_nr_zones(bdev->bd_disk)); + case BLKROGET: + return put_int(argp, bdev_read_only(bdev) != 0); + case BLKSSZGET: /* get block device logical block size */ + return put_int(argp, bdev_logical_block_size(bdev)); + case BLKPBSZGET: /* get block device physical block size */ + return put_uint(argp, bdev_physical_block_size(bdev)); + case BLKIOMIN: + return put_uint(argp, bdev_io_min(bdev)); + case BLKIOOPT: + return put_uint(argp, bdev_io_opt(bdev)); + case BLKALIGNOFF: + return put_int(argp, bdev_alignment_offset(bdev)); + case BLKDISCARDZEROES: + return put_uint(argp, 0); + case BLKSECTGET: + max_sectors = min_t(unsigned int, USHRT_MAX, + queue_max_sectors(bdev_get_queue(bdev))); + return put_ushort(argp, max_sectors); + case BLKROTATIONAL: + return put_ushort(argp, !blk_queue_nonrot(bdev_get_queue(bdev))); + case BLKRASET: + case BLKFRASET: + if(!capable(CAP_SYS_ADMIN)) + return -EACCES; + bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE; + return 0; + case BLKRRPART: + return blkdev_reread_part(bdev, mode); + case BLKTRACESTART: + case BLKTRACESTOP: + case BLKTRACETEARDOWN: + return blk_trace_ioctl(bdev, cmd, argp); + case IOC_PR_REGISTER: + return blkdev_pr_register(bdev, argp); + case IOC_PR_RESERVE: + return blkdev_pr_reserve(bdev, argp); + case IOC_PR_RELEASE: + return blkdev_pr_release(bdev, argp); + case IOC_PR_PREEMPT: + return blkdev_pr_preempt(bdev, argp, false); + case IOC_PR_PREEMPT_ABORT: + return blkdev_pr_preempt(bdev, argp, true); + case IOC_PR_CLEAR: + return blkdev_pr_clear(bdev, argp); + default: + return -ENOIOCTLCMD; + } +} + +/* + * Always keep this in sync with compat_blkdev_ioctl() + * to handle all incompatible commands in both functions. + * + * New commands must be compatible and go into blkdev_common_ioctl + */ +int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, + unsigned long arg) +{ + int ret; + loff_t size; + void __user *argp = (void __user *)arg; + + switch (cmd) { + /* These need separate implementations for the data structure */ + case HDIO_GETGEO: + return blkdev_getgeo(bdev, argp); + case BLKPG: + return blkpg_ioctl(bdev, argp); + + /* Compat mode returns 32-bit data instead of 'long' */ + case BLKRAGET: + case BLKFRAGET: + if (!argp) + return -EINVAL; + return put_long(argp, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512); + case BLKGETSIZE: + size = i_size_read(bdev->bd_inode); + if ((size >> 9) > ~0UL) + return -EFBIG; + return put_ulong(argp, size >> 9); + + /* The data is compatible, but the command number is different */ + case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ + return put_int(argp, block_size(bdev)); + case BLKBSZSET: + return blkdev_bszset(bdev, mode, argp); + case BLKGETSIZE64: + return put_u64(argp, i_size_read(bdev->bd_inode)); + + /* Incompatible alignment on i386 */ + case BLKTRACESETUP: + return blk_trace_ioctl(bdev, cmd, argp); + default: + break; + } + + ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp); + if (ret == -ENOIOCTLCMD) + return __blkdev_driver_ioctl(bdev, mode, cmd, arg); + + return ret; +} +EXPORT_SYMBOL_GPL(blkdev_ioctl); /* for /dev/raw */ + +#ifdef CONFIG_COMPAT + +#define BLKBSZGET_32 _IOR(0x12, 112, int) +#define BLKBSZSET_32 _IOW(0x12, 113, int) +#define BLKGETSIZE64_32 _IOR(0x12, 114, int) + +/* Most of the generic ioctls are handled in the normal fallback path. + This assumes the blkdev's low level compat_ioctl always returns + ENOIOCTLCMD for unknown ioctls. */ +long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg) +{ + int ret; + void __user *argp = compat_ptr(arg); + struct inode *inode = file->f_mapping->host; + struct block_device *bdev = inode->i_bdev; + struct gendisk *disk = bdev->bd_disk; + fmode_t mode = file->f_mode; + loff_t size; + + /* + * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have + * to updated it before every ioctl. + */ + if (file->f_flags & O_NDELAY) + mode |= FMODE_NDELAY; + else + mode &= ~FMODE_NDELAY; + + switch (cmd) { + /* These need separate implementations for the data structure */ + case HDIO_GETGEO: + return compat_hdio_getgeo(bdev, argp); + case BLKPG: + return compat_blkpg_ioctl(bdev, argp); + + /* Compat mode returns 32-bit data instead of 'long' */ + case BLKRAGET: + case BLKFRAGET: + if (!argp) + return -EINVAL; + return compat_put_long(argp, + (bdev->bd_bdi->ra_pages * PAGE_SIZE) / 512); + case BLKGETSIZE: + size = i_size_read(bdev->bd_inode); + if ((size >> 9) > ~(compat_ulong_t)0) + return -EFBIG; + return compat_put_ulong(argp, size >> 9); + + /* The data is compatible, but the command number is different */ + case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */ + return put_int(argp, bdev_logical_block_size(bdev)); + case BLKBSZSET_32: + return blkdev_bszset(bdev, mode, argp); + case BLKGETSIZE64_32: + return put_u64(argp, i_size_read(bdev->bd_inode)); + + /* Incompatible alignment on i386 */ + case BLKTRACESETUP32: + return blk_trace_ioctl(bdev, cmd, argp); + default: + break; + } + + ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp); + if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl) + ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg); + + return ret; +} +#endif |