Re: [PATCH v2 2/4] net: sched: tbf: handle GSO_BY_FRAGS case in enqueue

[Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>]

On Thu, Mar 01, 2018 at 05:13:38PM +1100, Daniel Axtens wrote:
> tbf_enqueue() checks the size of a packet before enqueuing it.
> However, the GSO size check does not consider the GSO_BY_FRAGS
> case, and so will drop GSO SCTP packets, causing a massive drop
> in throughput.
> 
> Use skb_gso_validate_mac_len() instead, as it does consider that
> case.
> 
> Signed-off-by: Daniel Axtens <dja@axtens.net>

Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>

> ---
>  net/sched/sch_tbf.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
> index 229172d509cc..03225a8df973 100644
> --- a/net/sched/sch_tbf.c
> +++ b/net/sched/sch_tbf.c
> @@ -188,7 +188,8 @@ static int tbf_enqueue(struct sk_buff *skb, struct Qdisc *sch,
>  	int ret;
>  
>  	if (qdisc_pkt_len(skb) > q->max_size) {
> -		if (skb_is_gso(skb) && skb_gso_mac_seglen(skb) <= q->max_size)
> +		if (skb_is_gso(skb) &&
> +		    skb_gso_validate_mac_len(skb, q->max_size))
>  			return tbf_segment(skb, sch, to_free);
>  		return qdisc_drop(skb, sch, to_free);
>  	}
> -- 
> 2.14.1
>