diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/block/loop.c | 45 | ||||
| -rw-r--r-- | drivers/block/ublk_drv.c | 37 |
2 files changed, 55 insertions, 27 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 32a3a5b13802..bd59c0e9508b 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1225,16 +1225,28 @@ static int loop_clr_fd(struct loop_device *lo) } static int -loop_set_status(struct loop_device *lo, const struct loop_info64 *info) +loop_set_status(struct loop_device *lo, blk_mode_t mode, + struct block_device *bdev, const struct loop_info64 *info) { int err; bool partscan = false; bool size_changed = false; unsigned int memflags; + /* + * If we don't hold exclusive handle for the device, upgrade to it + * here to avoid changing device under exclusive owner. + */ + if (!(mode & BLK_OPEN_EXCL)) { + err = bd_prepare_to_claim(bdev, loop_set_status, NULL); + if (err) + goto out_reread_partitions; + } + err = mutex_lock_killable(&lo->lo_mutex); if (err) - return err; + goto out_abort_claiming; + if (lo->lo_state != Lo_bound) { err = -ENXIO; goto out_unlock; @@ -1273,6 +1285,10 @@ out_unfreeze: } out_unlock: mutex_unlock(&lo->lo_mutex); +out_abort_claiming: + if (!(mode & BLK_OPEN_EXCL)) + bd_abort_claiming(bdev, loop_set_status); +out_reread_partitions: if (partscan) loop_reread_partitions(lo); @@ -1352,7 +1368,9 @@ loop_info64_to_old(const struct loop_info64 *info64, struct loop_info *info) } static int -loop_set_status_old(struct loop_device *lo, const struct loop_info __user *arg) +loop_set_status_old(struct loop_device *lo, blk_mode_t mode, + struct block_device *bdev, + const struct loop_info __user *arg) { struct loop_info info; struct loop_info64 info64; @@ -1360,17 +1378,19 @@ loop_set_status_old(struct loop_device *lo, const struct loop_info __user *arg) if (copy_from_user(&info, arg, sizeof (struct loop_info))) return -EFAULT; loop_info64_from_old(&info, &info64); - return loop_set_status(lo, &info64); + return loop_set_status(lo, mode, bdev, &info64); } static int -loop_set_status64(struct loop_device *lo, const struct loop_info64 __user *arg) +loop_set_status64(struct loop_device *lo, blk_mode_t mode, + struct block_device *bdev, + const struct loop_info64 __user *arg) { struct loop_info64 info64; if (copy_from_user(&info64, arg, sizeof (struct loop_info64))) return -EFAULT; - return loop_set_status(lo, &info64); + return loop_set_status(lo, mode, bdev, &info64); } static int @@ -1549,14 +1569,14 @@ static int lo_ioctl(struct block_device *bdev, blk_mode_t mode, case LOOP_SET_STATUS: err = -EPERM; if ((mode & BLK_OPEN_WRITE) || capable(CAP_SYS_ADMIN)) - err = loop_set_status_old(lo, argp); + err = loop_set_status_old(lo, mode, bdev, argp); break; case LOOP_GET_STATUS: return loop_get_status_old(lo, argp); case LOOP_SET_STATUS64: err = -EPERM; if ((mode & BLK_OPEN_WRITE) || capable(CAP_SYS_ADMIN)) - err = loop_set_status64(lo, argp); + err = loop_set_status64(lo, mode, bdev, argp); break; case LOOP_GET_STATUS64: return loop_get_status64(lo, argp); @@ -1650,8 +1670,9 @@ loop_info64_to_compat(const struct loop_info64 *info64, } static int -loop_set_status_compat(struct loop_device *lo, - const struct compat_loop_info __user *arg) +loop_set_status_compat(struct loop_device *lo, blk_mode_t mode, + struct block_device *bdev, + const struct compat_loop_info __user *arg) { struct loop_info64 info64; int ret; @@ -1659,7 +1680,7 @@ loop_set_status_compat(struct loop_device *lo, ret = loop_info64_from_compat(arg, &info64); if (ret < 0) return ret; - return loop_set_status(lo, &info64); + return loop_set_status(lo, mode, bdev, &info64); } static int @@ -1685,7 +1706,7 @@ static int lo_compat_ioctl(struct block_device *bdev, blk_mode_t mode, switch(cmd) { case LOOP_SET_STATUS: - err = loop_set_status_compat(lo, + err = loop_set_status_compat(lo, mode, bdev, (const struct compat_loop_info __user *)arg); break; case LOOP_GET_STATUS: diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 837fedb02e0d..f6e5a0766721 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -255,20 +255,6 @@ static inline struct request *__ublk_check_and_get_req(struct ublk_device *ub, u16 q_id, u16 tag, struct ublk_io *io, size_t offset); static inline unsigned int ublk_req_build_flags(struct request *req); -static void ublk_partition_scan_work(struct work_struct *work) -{ - struct ublk_device *ub = - container_of(work, struct ublk_device, partition_scan_work); - - if (WARN_ON_ONCE(!test_and_clear_bit(GD_SUPPRESS_PART_SCAN, - &ub->ub_disk->state))) - return; - - mutex_lock(&ub->ub_disk->open_mutex); - bdev_disk_changed(ub->ub_disk, false); - mutex_unlock(&ub->ub_disk->open_mutex); -} - static inline struct ublksrv_io_desc * ublk_get_iod(const struct ublk_queue *ubq, unsigned tag) { @@ -1597,6 +1583,27 @@ static void ublk_put_disk(struct gendisk *disk) put_device(disk_to_dev(disk)); } +static void ublk_partition_scan_work(struct work_struct *work) +{ + struct ublk_device *ub = + container_of(work, struct ublk_device, partition_scan_work); + /* Hold disk reference to prevent UAF during concurrent teardown */ + struct gendisk *disk = ublk_get_disk(ub); + + if (!disk) + return; + + if (WARN_ON_ONCE(!test_and_clear_bit(GD_SUPPRESS_PART_SCAN, + &disk->state))) + goto out; + + mutex_lock(&disk->open_mutex); + bdev_disk_changed(disk, false); + mutex_unlock(&disk->open_mutex); +out: + ublk_put_disk(disk); +} + /* * Use this function to ensure that ->canceling is consistently set for * the device and all queues. Do not set these flags directly. @@ -2041,7 +2048,7 @@ static void ublk_stop_dev(struct ublk_device *ub) mutex_lock(&ub->mutex); ublk_stop_dev_unlocked(ub); mutex_unlock(&ub->mutex); - flush_work(&ub->partition_scan_work); + cancel_work_sync(&ub->partition_scan_work); ublk_cancel_dev(ub); } |