diff options
| -rw-r--r-- | include/uapi/linux/pkt_sched.h | 2 | ||||
| -rw-r--r-- | net/sched/sch_fq.c | 19 |
2 files changed, 19 insertions, 2 deletions
diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h index d62316baae94..534b84710745 100644 --- a/include/uapi/linux/pkt_sched.h +++ b/include/uapi/linux/pkt_sched.h @@ -774,6 +774,8 @@ enum { TCA_FQ_FLOW_REFILL_DELAY, /* flow credit refill delay in usec */ + TCA_FQ_ORPHAN_MASK, /* mask applied to orphaned skb hashes */ + __TCA_FQ_MAX }; diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c index 69a3dbf55c60..a00c43043001 100644 --- a/net/sched/sch_fq.c +++ b/net/sched/sch_fq.c @@ -93,6 +93,7 @@ struct fq_sched_data { u32 flow_refill_delay; u32 flow_max_rate; /* optional max rate per flow */ u32 flow_plimit; /* max packets per flow */ + u32 orphan_mask; /* mask for orphaned skb */ struct rb_root *fq_root; u8 rate_enable; u8 fq_trees_log; @@ -223,11 +224,20 @@ static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q) if (unlikely((skb->priority & TC_PRIO_MAX) == TC_PRIO_CONTROL)) return &q->internal; - if (unlikely(!sk)) { + /* SYNACK messages are attached to a listener socket. + * 1) They are not part of a 'flow' yet + * 2) We do not want to rate limit them (eg SYNFLOOD attack), + * especially if the listener set SO_MAX_PACING_RATE + * 3) We pretend they are orphaned + */ + if (!sk || sk->sk_state == TCP_LISTEN) { + unsigned long hash = skb_get_hash(skb) & q->orphan_mask; + /* By forcing low order bit to 1, we make sure to not * collide with a local flow (socket pointers are word aligned) */ - sk = (struct sock *)(skb_get_hash(skb) | 1L); + sk = (struct sock *)((hash << 1) | 1UL); + skb_orphan(skb); } root = &q->fq_root[hash_32((u32)(long)sk, q->fq_trees_log)]; @@ -704,6 +714,9 @@ static int fq_change(struct Qdisc *sch, struct nlattr *opt) q->flow_refill_delay = usecs_to_jiffies(usecs_delay); } + if (tb[TCA_FQ_ORPHAN_MASK]) + q->orphan_mask = nla_get_u32(tb[TCA_FQ_ORPHAN_MASK]); + if (!err) { sch_tree_unlock(sch); err = fq_resize(sch, fq_log); @@ -749,6 +762,7 @@ static int fq_init(struct Qdisc *sch, struct nlattr *opt) q->delayed = RB_ROOT; q->fq_root = NULL; q->fq_trees_log = ilog2(1024); + q->orphan_mask = 1024 - 1; qdisc_watchdog_init(&q->watchdog, sch); if (opt) @@ -778,6 +792,7 @@ static int fq_dump(struct Qdisc *sch, struct sk_buff *skb) nla_put_u32(skb, TCA_FQ_FLOW_MAX_RATE, q->flow_max_rate) || nla_put_u32(skb, TCA_FQ_FLOW_REFILL_DELAY, jiffies_to_usecs(q->flow_refill_delay)) || + nla_put_u32(skb, TCA_FQ_ORPHAN_MASK, q->orphan_mask) || nla_put_u32(skb, TCA_FQ_BUCKETS_LOG, q->fq_trees_log)) goto nla_put_failure; |