From: Yufen Yu
ohos inclusion
category: bugfix
issue: #I3ZXZF
CVE: NA
-------------------------------------------------
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.
Link: https://lore.kernel.org/linux-block/20210608092707.1062259-1-yuyufen@huawei....
Signed-off-by: Yufen Yu
Reviewed-by: Jason Yan
Signed-off-by: Chen Jun
Signed-off-by: Yu Changchun
---
block/partitions/core.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)
diff --git a/block/partitions/core.c b/block/partitions/core.c
index a02e22411594..758ecc3de802 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -519,17 +519,26 @@ int bdev_add_partition(struct block_device *bdev, int partno,
sector_t start, sector_t length)
{
struct hd_struct *part;
+ struct gendisk *disk = bdev->bd_disk;
+ int ret;
mutex_lock(&bdev->bd_mutex);
- if (partition_overlaps(bdev->bd_disk, start, length, -1)) {
- mutex_unlock(&bdev->bd_mutex);
- return -EBUSY;
+ if (!(disk->flags & GENHD_FL_UP)) {
+ ret = -ENXIO;
+ goto out;
+ }
+
+ if (partition_overlaps(disk, start, length, -1)) {
+ ret = -EBUSY;
+ goto out;
}
- part = add_partition(bdev->bd_disk, partno, start, length,
+ part = add_partition(disk, partno, start, length,
ADDPART_FLAG_NONE, NULL);
+ ret = PTR_ERR_OR_ZERO(part);
+out:
mutex_unlock(&bdev->bd_mutex);
- return PTR_ERR_OR_ZERO(part);
+ return ret;
}
int bdev_del_partition(struct block_device *bdev, int partno)
--
2.22.0
