* [PATCH v2] block: check disk exist before trying to add partition
@ 2021-06-10 2:32 Yufen Yu
2021-06-29 8:47 ` Yufen Yu
2021-07-01 1:39 ` Jens Axboe
0 siblings, 2 replies; 3+ messages in thread
From: Yufen Yu @ 2021-06-10 2:32 UTC (permalink / raw)
To: axboe; +Cc: linux-block, Yufen Yu, Jan Kara, Christoph Hellwig
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 <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
---
block/partitions/core.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/block/partitions/core.c b/block/partitions/core.c
index 186d4fbd9f09..b123ccb2cf64 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -454,17 +454,26 @@ 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;
+ }
+
+ 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);
- 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)
--
2.25.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v2] block: check disk exist before trying to add partition
2021-06-10 2:32 [PATCH v2] block: check disk exist before trying to add partition Yufen Yu
@ 2021-06-29 8:47 ` Yufen Yu
2021-07-01 1:39 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Yufen Yu @ 2021-06-29 8:47 UTC (permalink / raw)
To: axboe; +Cc: linux-block, Jan Kara, Christoph Hellwig
Hi, Jens
This patch is based on for-5.14/block branch. Please consider to
apply it.
Thansk,
Yufen
On 2021/6/10 10:32, Yufen Yu wrote:
> 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 <jack@suse.cz>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Yufen Yu <yuyufen@huawei.com>
> ---
> block/partitions/core.c | 23 ++++++++++++++++-------
> 1 file changed, 16 insertions(+), 7 deletions(-)
>
> diff --git a/block/partitions/core.c b/block/partitions/core.c
> index 186d4fbd9f09..b123ccb2cf64 100644
> --- a/block/partitions/core.c
> +++ b/block/partitions/core.c
> @@ -454,17 +454,26 @@ 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;
> + }
> +
> + 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);
> - 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)
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v2] block: check disk exist before trying to add partition
2021-06-10 2:32 [PATCH v2] block: check disk exist before trying to add partition Yufen Yu
2021-06-29 8:47 ` Yufen Yu
@ 2021-07-01 1:39 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2021-07-01 1:39 UTC (permalink / raw)
To: Yufen Yu; +Cc: linux-block, Jan Kara, Christoph Hellwig
On 6/9/21 8:32 PM, Yufen Yu wrote:
> 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.
Applied, thanks.
--
Jens Axboe
^ permalink raw reply [flat|nested] 3+ messages in thread
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