Re: [PATCH] block: fix device_add_disk() kobject_create_and_add() error handling

[Wu Bo]

On 2021/11/4 0:40, Luis Chamberlain wrote:
> Commit 83cbce957446 ("block: add error handling for device_add_disk /
> add_disk") added error handling to device_add_disk(), however the goto
> label for the kobject_create_and_add() failure did not set the return
> value correctly, and so we can end up in a situation where
> kobject_create_and_add() fails but we report success.
>
> Fixes: 83cbce957446 ("block: add error handling for device_add_disk / add_disk")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> ---
>   block/genhd.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/block/genhd.c b/block/genhd.c
> index be4775c13760..b0b484116c3a 100644
> --- a/block/genhd.c
> +++ b/block/genhd.c
> @@ -478,8 +478,10 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
>   	if (!disk->part0->bd_holder_dir)

in here also should be add ret = -ENOMEM;

>   		goto out_del_integrity;
>   	disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
> -	if (!disk->slave_dir)
> +	if (!disk->slave_dir) {
> +		ret = -ENOMEM;
>   		goto out_put_holder_dir;
> +	}
>   
>   	ret = bd_register_pending_holders(disk);
>   	if (ret < 0)