From b5cfbd35eccaa0b532dc0d8a31e4d59b5e314c93 Mon Sep 17 00:00:00 2001 From: Yufen Yu Date: Thu, 10 Jun 2021 10:32:41 +0800 Subject: block: check disk exist before trying to add partition If disk have been deleted, we should return fail for ioctl BLKPG_DEL_PARTITION. Otherwise, the directory /sys/class/block may remain invalid symlinks file. The race as following: blkdev_open del_gendisk disk->flags &= ~GENHD_FL_UP; blk_drop_partitions blkpg_ioctl bdev_add_partition add_partition device_add device_add_class_symlinks ioctl may add_partition after del_gendisk() have tried to delete partitions. Then, symlinks file will be created. Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Signed-off-by: Yufen Yu Link: https://lore.kernel.org/r/20210610023241.3646241-1-yuyufen@huawei.com Signed-off-by: Jens Axboe --- block/partitions/core.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) (limited to 'block/partitions') diff --git a/block/partitions/core.c b/block/partitions/core.c index 347c56a51d87..ed78cdfe054b 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -453,17 +453,26 @@ int bdev_add_partition(struct block_device *bdev, int partno, sector_t start, sector_t length) { struct block_device *part; + struct gendisk *disk = bdev->bd_disk; + int ret; - mutex_lock(&bdev->bd_disk->open_mutex); - if (partition_overlaps(bdev->bd_disk, start, length, -1)) { - mutex_unlock(&bdev->bd_disk->open_mutex); - return -EBUSY; + mutex_lock(&disk->open_mutex); + if (!(disk->flags & GENHD_FL_UP)) { + ret = -ENXIO; + goto out; } - part = add_partition(bdev->bd_disk, partno, start, length, + if (partition_overlaps(disk, start, length, -1)) { + ret = -EBUSY; + goto out; + } + + part = add_partition(disk, partno, start, length, ADDPART_FLAG_NONE, NULL); - mutex_unlock(&bdev->bd_disk->open_mutex); - return PTR_ERR_OR_ZERO(part); + ret = PTR_ERR_OR_ZERO(part); +out: + mutex_unlock(&disk->open_mutex); + return ret; } int bdev_del_partition(struct block_device *bdev, int partno) -- cgit