diff options
Diffstat (limited to 'net/sched/sch_fq.c')
| -rw-r--r-- | net/sched/sch_fq.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c index 333cd94ba381..dfcea20e3171 100644 --- a/net/sched/sch_fq.c +++ b/net/sched/sch_fq.c @@ -1,7 +1,7 @@ /* * net/sched/sch_fq.c Fair Queue Packet Scheduler (per flow pacing) * - * Copyright (C) 2013 Eric Dumazet <edumazet@google.com> + * Copyright (C) 2013-2015 Eric Dumazet <edumazet@google.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -52,6 +52,7 @@ #include <net/pkt_sched.h> #include <net/sock.h> #include <net/tcp_states.h> +#include <net/tcp.h> /* * Per flow structure, dynamically allocated @@ -92,6 +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; @@ -222,11 +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)]; @@ -445,7 +456,9 @@ begin: goto begin; } - if (unlikely(f->head && now < f->time_next_packet)) { + skb = f->head; + if (unlikely(skb && now < f->time_next_packet && + !skb_is_tcp_pure_ack(skb))) { head->first = f->next; fq_flow_set_throttled(q, f); goto begin; @@ -464,14 +477,17 @@ begin: goto begin; } prefetch(&skb->end); - f->time_next_packet = now; f->credit -= qdisc_pkt_len(skb); if (f->credit > 0 || !q->rate_enable) goto out; + /* Do not pace locally generated ack packets */ + if (skb_is_tcp_pure_ack(skb)) + goto out; + rate = q->flow_max_rate; - if (skb->sk && skb->sk->sk_state != TCP_TIME_WAIT) + if (skb->sk) rate = min(skb->sk->sk_pacing_rate, rate); if (rate != ~0U) { @@ -704,6 +720,9 @@ 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 +768,7 @@ 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 +798,7 @@ 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; |