Re: [PATCH] sysfs: don't remove existing directory on update failure

[Danilo Krummrich]

On Wed May 20, 2026 at 3:05 PM CEST, Greg Kroah-Hartman wrote:
> When sysfs_update_group() is called for a named group and create_files()
> fails (e.g. -ENOMEM), internal_create_group() calls kernfs_remove(kn) on
> the group directory.  In the update path, kn was obtained via
> kernfs_find_and_get() and refers to a directory that already existed
> before this call.  Removing it silently destroys a sysfs group that the
> caller did not create.
>
> Only remove the directory if we created it ourselves.  On update failure
> the directory remains as it is left empty by remove_files() inside
> create_files(), but can be repopulated by a retry.
>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Cc: Danilo Krummrich <dakr@xxxxxxxxxx>
> Cc: Rajat Jain <rajatja@xxxxxxxxxx>
> Fixes: c855cf2759d2 ("sysfs: Fix internal_create_group() for named group updates")
> Cc: stable <stable@xxxxxxxxxx>
> Assisted-by: gkh_clanker_t1000
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Reviewed-by: Danilo Krummrich <dakr@xxxxxxxxxx>