Merge tag 'asoc-v4.1' into asoc-next

[firefly-linux-kernel-4.4.55.git] / net / sched / sch_fq.c

diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c
index 333cd94ba381ff62f9512d6b95474a2aecc3ea88..dfcea20e31711288aea660add30248b442769979 100644 (file)
--- 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;