Re: [PATCH v2] sysfs: Fix internal_create_group() for named group updates

From: Greg Kroah-Hartman
Date: Sat Jun 16 2018 - 04:38:11 EST


On Sat, Jun 16, 2018 at 01:18:37AM -0700, Rajat Jain wrote:
> There are a couple of problems with named group updates in the code
> today:
>
> * sysfs_update_group() will always fail for a named group, because
> internal_create_group() will try to create a new sysfs directory
> unconditionally, which will ofcourse fail with -EEXIST.
>
> * We can leak the kernfs_node for grp->name if some one tries to:
> - rename a group (change grp->name), or
> - update a named group, to an unnamed group
>
> It appears that the whole purpose of sysfs_update_group() was to
> allow changing the permissions or visibility of attributes and not
> the names. So make it clear in the comments, and allow it to update
> an existing named group.
>
> Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
> ---
> v2: Use pr_warn() instead of WARN()

Looks good, I'll queue it up after 4.18-rc1 is out, thanks for the
update so quickly.

greg k-h