Re: [PATCH 067/190] Revert "net: caif: replace BUG_ON with recovery code"

[Greg Kroah-Hartman]

On Wed, Apr 21, 2021 at 02:59:02PM +0200, Greg Kroah-Hartman wrote:
> This reverts commit c5dea815834c7d2e9fc633785455bc428b7a1956.
> 
> 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: Aditya Pakki <pakki001@xxxxxxx>
> Cc: David S. Miller <davem@xxxxxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/caif/caif_serial.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c
> index 8215cd77301f..4720a7bac4fb 100644
> --- a/drivers/net/caif/caif_serial.c
> +++ b/drivers/net/caif/caif_serial.c
> @@ -269,9 +269,7 @@ static netdev_tx_t caif_xmit(struct sk_buff *skb, struct net_device *dev)
>  {
>  	struct ser_device *ser;
>  
> -	if (WARN_ON(!dev))
> -		return -EINVAL;
> -
> +	BUG_ON(dev == NULL);
>  	ser = netdev_priv(dev);
>  
>  	/* Send flow off once, on high water mark */
> -- 
> 2.31.1
> 

This commit was pointless, the check should just be removed entirely as
it is impossible to hit.  I'll keep the revert and fix it up properly in
a follow-on patch.

thanks,

greg k-h