block: add put_device() call when device_add() fails in device_add_disk()

Message ID 20240221220141.32316-1-alfredo.carlon@gmail.com
State New
Headers
Series block: add put_device() call when device_add() fails in device_add_disk() |

Commit Message

Alfredo Cruz Feb. 21, 2024, 10:01 p.m. UTC
  When device_add() fails, put_device() should called for cleanup.
Added this call before the jump to out_free_ext_minor to not
interfere with device_del() on error paths where deivce_add() succeeded

Signed-off-by: Alfredo Cruz <alfredo.carlon@gmail.com>
---
 block/genhd.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
  

Comments

Yu Kuai Feb. 22, 2024, 9:22 a.m. UTC | #1
Hi,

在 2024/02/22 6:01, Alfredo Cruz 写道:
> When device_add() fails, put_device() should called for cleanup.
> Added this call before the jump to out_free_ext_minor to not
> interfere with device_del() on error paths where deivce_add() succeeded
> 
> Signed-off-by: Alfredo Cruz <alfredo.carlon@gmail.com>
> ---
>   block/genhd.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/block/genhd.c b/block/genhd.c
> index d74fb5b4ae68..5a231fb075bd 100644
> --- a/block/genhd.c
> +++ b/block/genhd.c
> @@ -456,8 +456,10 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
>   	if (!(disk->flags & GENHD_FL_HIDDEN))
>   		ddev->devt = MKDEV(disk->major, disk->first_minor);
>   	ret = device_add(ddev);
> -	if (ret)
> +	if (ret) {
> +		put_device(ddev);
>   		goto out_free_ext_minor;
> +	}

This is wrong, gendisk is allocated by caller, and caller is responsible
to free the gendisk, as you can see in many callers.

Thanks,
Kuai

>   
>   	ret = disk_alloc_events(disk);
>   	if (ret)
>
  

Patch

diff --git a/block/genhd.c b/block/genhd.c
index d74fb5b4ae68..5a231fb075bd 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -456,8 +456,10 @@  int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
 	if (!(disk->flags & GENHD_FL_HIDDEN))
 		ddev->devt = MKDEV(disk->major, disk->first_minor);
 	ret = device_add(ddev);
-	if (ret)
+	if (ret) {
+		put_device(ddev);
 		goto out_free_ext_minor;
+	}
 
 	ret = disk_alloc_events(disk);
 	if (ret)