Re: [PATCH net-next v8 4/4] net/sched: cake: hash before segmenting and reject an overlong split

[Paolo Abeni <pabeni@redhat.com>]

On 10/24/26 19:30, netdev-bot+sashiko@kernel.org wrote:
>> @@ -1784,12 +1811,49 @@ static s32 cake_enqueue(struct sk_buff *skb, struct Qdisc *sch,
>>   					 QDISC_DROP_OVERLIMIT);
>>   	}
>>   
>> -	/* choose flow to insert into */
>> +	/* Select the tin and extract the keys before segmenting:
>> +	 * skb_gso_segment() rewrites encapsulated headers, which
>> +	 * changes the keys.
>> +	 */
>>   	b = cake_select_tin(sch, skb);
>> -	idx = cake_hash(b, skb, q->config->flow_mode, flow_override,
>> -			host_override) + 1;
>> +	cake_hash_keys(skb, flow_mode, flow_override, host_override, &keys);
>> +
>> +	if (qdisc_pkt_segs(skb) > 1 && q->config->rate_flags & CAKE_FLAG_SPLIT_GSO) {
>> +		netdev_features_t features = netif_skb_features(skb);
>> +		struct sk_buff *nskb, *seg;
>> +
>> +		segs = skb_gso_segment(skb, features & ~NETIF_F_GSO_MASK);
>> +		if (IS_ERR_OR_NULL(segs))
>> +			return qdisc_drop(skb, sch, to_free);
> 
> [Severity: Medium]
> Can this qdisc_drop() report a bogus drop reason for the original skb?

I'm sorry forcing another iteration, but this looks real, and should be
easily fixable.

Thanks,

Paolo