Re: [PATCH 141/190] Revert "libertas: add checks for the return value of sysfs_create_group"

[Greg Kroah-Hartman]

On Wed, Apr 21, 2021 at 03:00:16PM +0200, Greg Kroah-Hartman wrote:
> This reverts commit 434256833d8eb988cb7f3b8a41699e2fe48d9332.
> 
> Commits from @umn.edu addresses have been found to be submitted in "bad
> faith" to try to test the kernel community's ability to review "known
> malicious" changes.  The result of these submissions can be found in a
> paper published at the 42nd IEEE Symposium on Security and Privacy
> entitled, "Open Source Insecurity: Stealthily Introducing
> Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University
> of Minnesota) and Kangjie Lu (University of Minnesota).
> 
> Because of this, all submissions from this group must be reverted from
> the kernel tree and will need to be re-reviewed again to determine if
> they actually are a valid fix.  Until that work is complete, remove this
> change to ensure that no problems are being introduced into the
> codebase.
> 
> Cc: Kangjie Lu <kjlu@xxxxxxx>
> Cc: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/wireless/marvell/libertas/mesh.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/drivers/net/wireless/marvell/libertas/mesh.c b/drivers/net/wireless/marvell/libertas/mesh.c
> index f5b78257d551..c611e6668b21 100644
> --- a/drivers/net/wireless/marvell/libertas/mesh.c
> +++ b/drivers/net/wireless/marvell/libertas/mesh.c
> @@ -805,12 +805,7 @@ static void lbs_persist_config_init(struct net_device *dev)
>  {
>  	int ret;
>  	ret = sysfs_create_group(&(dev->dev.kobj), &boot_opts_group);
> -	if (ret)
> -		pr_err("failed to create boot_opts_group.\n");
> -
>  	ret = sysfs_create_group(&(dev->dev.kobj), &mesh_ie_group);
> -	if (ret)
> -		pr_err("failed to create mesh_ie_group.\n");
>  }
>  
>  static void lbs_persist_config_remove(struct net_device *dev)
> -- 
> 2.31.1
> 

The original change here is incorrect, the error needs to be propagated
back to the caller AND if the second group call fails, the first needs
to be removed.  There are much better ways to solve this, the driver
should NOT be calling sysfs_create_group() on its own as it is racing
userspace and loosing.  I will keep this revert and fix it up properly
in a follow-on patch.

thanks,

greg k-h