[PATCH] block: fix resource leak in blk_register_queue() error path

[PATCH] block: fix resource leak in blk_register_queue() error path

[Zheng Qixing]

From: Zheng Qixing <zhengqixing@huawei.com>

When registering a queue fails after blk_mq_sysfs_register() is
successful but the function later encounters an error, we need
to clean up the blk_mq_sysfs resources.

Add the missing blk_mq_sysfs_unregister() call in the error path
to properly clean up these resources and prevent a memory leak.

Fixes: 320ae51feed5 ("blk-mq: new multi-queue block IO queueing mechanism")
Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
---
 block/blk-sysfs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index a2882751f0d2..1f9b45b0b9ee 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -909,6 +909,8 @@ int blk_register_queue(struct gendisk *disk)
 out_debugfs_remove:
 	blk_debugfs_remove(disk);
 	mutex_unlock(&q->sysfs_lock);
+	if (queue_is_mq(q))
+		blk_mq_sysfs_unregister(disk);
 out_put_queue_kobj:
 	kobject_put(&disk->queue_kobj);
 	return ret;
-- 
2.39.2

Re: [PATCH] block: fix resource leak in blk_register_queue() error path

[Yu Kuai]

在 2025/04/12 17:25, Zheng Qixing 写道:
> From: Zheng Qixing <zhengqixing@huawei.com>
> 
> When registering a queue fails after blk_mq_sysfs_register() is
> successful but the function later encounters an error, we need
> to clean up the blk_mq_sysfs resources.
> 
> Add the missing blk_mq_sysfs_unregister() call in the error path
> to properly clean up these resources and prevent a memory leak.
> 
> Fixes: 320ae51feed5 ("blk-mq: new multi-queue block IO queueing mechanism")
> Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
> ---
>   block/blk-sysfs.c | 2 ++
>   1 file changed, 2 insertions(+)
> 

LGTM
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
> diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
> index a2882751f0d2..1f9b45b0b9ee 100644
> --- a/block/blk-sysfs.c
> +++ b/block/blk-sysfs.c
> @@ -909,6 +909,8 @@ int blk_register_queue(struct gendisk *disk)
>   out_debugfs_remove:
>   	blk_debugfs_remove(disk);
>   	mutex_unlock(&q->sysfs_lock);
> +	if (queue_is_mq(q))
> +		blk_mq_sysfs_unregister(disk);
>   out_put_queue_kobj:
>   	kobject_put(&disk->queue_kobj);
>   	return ret;
> 

Re: [PATCH] block: fix resource leak in blk_register_queue() error path

[Christoph Hellwig]

Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH] block: fix resource leak in blk_register_queue() error path

[Jens Axboe]

On Sat, 12 Apr 2025 17:25:54 +0800, Zheng Qixing wrote:
> When registering a queue fails after blk_mq_sysfs_register() is
> successful but the function later encounters an error, we need
> to clean up the blk_mq_sysfs resources.
> 
> Add the missing blk_mq_sysfs_unregister() call in the error path
> to properly clean up these resources and prevent a memory leak.
> 
> [...]

Applied, thanks!

[1/1] block: fix resource leak in blk_register_queue() error path
      commit: 40f2eb9b531475dd01b683fdaf61ca3cfd03a51e

Best regards,
-- 
Jens Axboe