Commit 02341a08 authored by Yu Kuai's avatar Yu Kuai Committed by Jens Axboe
Browse files

block: fix memory leak for elevator on add_disk failure 



The default elevator is allocated in the beginning of device_add_disk(),
however, it's not freed in the following error path.

Fixes: 50e34d78 ("block: disable the elevator int del_gendisk")
Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20221022021615.2756171-1-yukuai1@huaweicloud.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 2db96217

block/genhd.c

+8 −4
Original line number Diff line number Diff line
@@ -410,9 +410,10 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, 
	 * Otherwise just allocate the device numbers for both the whole device

	 * and all partitions from the extended dev_t space.

	 */

	ret = -EINVAL;

	if (disk->major) {

		if (WARN_ON(!disk->minors))

			return -EINVAL;

			goto out_exit_elevator;



		if (disk->minors > DISK_MAX_PARTS) {

			pr_err("block: can't allocate more than %d partitions\n",
@@ -420,14 +421,14 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, 
			disk->minors = DISK_MAX_PARTS;

		}

		if (disk->first_minor + disk->minors > MINORMASK + 1)

			return -EINVAL;

			goto out_exit_elevator;

	} else {

		if (WARN_ON(disk->minors))

			return -EINVAL;

			goto out_exit_elevator;



		ret = blk_alloc_ext_minor();

		if (ret < 0)

			return ret;

			goto out_exit_elevator;

		disk->major = BLOCK_EXT_MAJOR;

		disk->first_minor = ret;

	}
@@ -540,6 +541,9 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, 
out_free_ext_minor:

	if (disk->major == BLOCK_EXT_MAJOR)

		blk_free_ext_minor(disk->first_minor);

out_exit_elevator:

	if (disk->queue->elevator)

		elevator_exit(disk->queue);

	return ret;

}

EXPORT_SYMBOL(device_add_disk);