1. 28 10月, 2017 4 次提交
  2. 27 10月, 2017 15 次提交
  3. 26 10月, 2017 1 次提交
  4. 24 10月, 2017 1 次提交
    • C
      tcp: Configure TFO without cookie per socket and/or per route · 71c02379
      Christoph Paasch 提交于
      We already allow to enable TFO without a cookie by using the
      fastopen-sysctl and setting it to TFO_SERVER_COOKIE_NOT_REQD (or
      TFO_CLIENT_NO_COOKIE).
      This is safe to do in certain environments where we know that there
      isn't a malicous host (aka., data-centers) or when the
      application-protocol already provides an authentication mechanism in the
      first flight of data.
      
      A server however might be providing multiple services or talking to both
      sides (public Internet and data-center). So, this server would want to
      enable cookie-less TFO for certain services and/or for connections that
      go to the data-center.
      
      This patch exposes a socket-option and a per-route attribute to enable such
      fine-grained configurations.
      Signed-off-by: NChristoph Paasch <cpaasch@apple.com>
      Reviewed-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      71c02379
  5. 20 10月, 2017 2 次提交
  6. 13 10月, 2017 1 次提交
  7. 12 10月, 2017 1 次提交
    • E
      tcp: fix tcp_unlink_write_queue() · 4a269818
      Eric Dumazet 提交于
      Yury reported crash with this signature :
      
      [  554.034021] [<ffff80003ccd5a58>] 0xffff80003ccd5a58
      [  554.034156] [<ffff00000888fd34>] skb_release_all+0x14/0x30
      [  554.034288] [<ffff00000888fd64>] __kfree_skb+0x14/0x28
      [  554.034409] [<ffff0000088ece6c>] tcp_sendmsg_locked+0x4dc/0xcc8
      [  554.034541] [<ffff0000088ed68c>] tcp_sendmsg+0x34/0x58
      [  554.034659] [<ffff000008919fd4>] inet_sendmsg+0x2c/0xf8
      [  554.034783] [<ffff0000088842e8>] sock_sendmsg+0x18/0x30
      [  554.034928] [<ffff0000088861fc>] SyS_sendto+0x84/0xf8
      
      Problem is that skb->destructor contains garbage, and this is
      because I accidentally removed tcp_skb_tsorted_anchor_cleanup()
      from tcp_unlink_write_queue()
      
      This would trigger with a write(fd, <invalid_memory>, len) attempt,
      and we will add to packetdrill this capability to avoid future
      regressions.
      
      Fixes: 75c119af ("tcp: implement rb-tree based retransmit queue")
      Reported-by: NYury Norov <ynorov@caviumnetworks.com>
      Tested-by: NYury Norov <ynorov@caviumnetworks.com>
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4a269818
  8. 07 10月, 2017 2 次提交
    • E
      tcp: implement rb-tree based retransmit queue · 75c119af
      Eric Dumazet 提交于
      Using a linear list to store all skbs in write queue has been okay
      for quite a while : O(N) is not too bad when N < 500.
      
      Things get messy when N is the order of 100,000 : Modern TCP stacks
      want 10Gbit+ of throughput even with 200 ms RTT flows.
      
      40 ns per cache line miss means a full scan can use 4 ms,
      blowing away CPU caches.
      
      SACK processing often can use various hints to avoid parsing
      whole retransmit queue. But with high packet losses and/or high
      reordering, hints no longer work.
      
      Sender has to process thousands of unfriendly SACK, accumulating
      a huge socket backlog, burning a cpu and massively dropping packets.
      
      Using an rb-tree for retransmit queue has been avoided for years
      because it added complexity and overhead, but now is the time
      to be more resistant and say no to quadratic behavior.
      
      1) RTX queue is no longer part of the write queue : already sent skbs
      are stored in one rb-tree.
      
      2) Since reaching the head of write queue no longer needs
      sk->sk_send_head, we added an union of sk_send_head and tcp_rtx_queue
      
      Tested:
      
       On receiver :
       netem on ingress : delay 150ms 200us loss 1
       GRO disabled to force stress and SACK storms.
      
      for f in `seq 1 10`
      do
       ./netperf -H lpaa6 -l30 -- -K bbr -o THROUGHPUT|tail -1
      done | awk '{print $0} {sum += $0} END {printf "%7u\n",sum}'
      
      Before patch :
      
      323.87
      351.48
      339.59
      338.62
      306.72
      204.07
      304.93
      291.88
      202.47
      176.88
         2840
      
      After patch:
      
      1700.83
      2207.98
      2070.17
      1544.26
      2114.76
      2124.89
      1693.14
      1080.91
      2216.82
      1299.94
        18053
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      75c119af
    • E
      tcp: uninline tcp_write_queue_purge() · ac3f09ba
      Eric Dumazet 提交于
      Since the upcoming rtx rbtree will add some extra code,
      it is time to not inline this fat function anymore.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ac3f09ba
  9. 06 10月, 2017 2 次提交
    • E
      tcp: new list for sent but unacked skbs for RACK recovery · e2080072
      Eric Dumazet 提交于
      This patch adds a new queue (list) that tracks the sent but not yet
      acked or SACKed skbs for a TCP connection. The list is chronologically
      ordered by skb->skb_mstamp (the head is the oldest sent skb).
      
      This list will be used to optimize TCP Rack recovery, which checks
      an skb's timestamp to judge if it has been lost and needs to be
      retransmitted. Since TCP write queue is ordered by sequence instead
      of sent time, RACK has to scan over the write queue to catch all
      eligible packets to detect lost retransmission, and iterates through
      SACKed skbs repeatedly.
      
      Special cares for rare events:
      1. TCP repair fakes skb transmission so the send queue needs adjusted
      2. SACK reneging would require re-inserting SACKed skbs into the
         send queue. For now I believe it's not worth the complexity to
         make RACK work perfectly on SACK reneging, so we do nothing here.
      3. Fast Open: currently for non-TFO, send-queue correctly queues
         the pure SYN packet. For TFO which queues a pure SYN and
         then a data packet, send-queue only queues the data packet but
         not the pure SYN due to the structure of TFO code. This is okay
         because the SYN receiver would never respond with a SACK on a
         missing SYN (i.e. SYN is never fast-retransmitted by SACK/RACK).
      
      In order to not grow sk_buff, we use an union for the new list and
      _skb_refdst/destructor fields. This is a bit complicated because
      we need to make sure _skb_refdst and destructor are properly zeroed
      before skb is cloned/copied at transmit, and before being freed.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NNeal Cardwell <ncardwell@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e2080072
    • W
      tcp: uniform the set up of sockets after successful connection · 27204aaa
      Wei Wang 提交于
      Currently in the TCP code, the initialization sequence for cached
      metrics, congestion control, BPF, etc, after successful connection
      is very inconsistent. This introduces inconsistent bevhavior and is
      prone to bugs. The current call sequence is as follows:
      
      (1) for active case (tcp_finish_connect() case):
              tcp_mtup_init(sk);
              icsk->icsk_af_ops->rebuild_header(sk);
              tcp_init_metrics(sk);
              tcp_call_bpf(sk, BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB);
              tcp_init_congestion_control(sk);
              tcp_init_buffer_space(sk);
      
      (2) for passive case (tcp_rcv_state_process() TCP_SYN_RECV case):
              icsk->icsk_af_ops->rebuild_header(sk);
              tcp_call_bpf(sk, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB);
              tcp_init_congestion_control(sk);
              tcp_mtup_init(sk);
              tcp_init_buffer_space(sk);
              tcp_init_metrics(sk);
      
      (3) for TFO passive case (tcp_fastopen_create_child()):
              inet_csk(child)->icsk_af_ops->rebuild_header(child);
              tcp_init_congestion_control(child);
              tcp_mtup_init(child);
              tcp_init_metrics(child);
              tcp_call_bpf(child, BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB);
              tcp_init_buffer_space(child);
      
      This commit uniforms the above functions to have the following sequence:
              tcp_mtup_init(sk);
              icsk->icsk_af_ops->rebuild_header(sk);
              tcp_init_metrics(sk);
              tcp_call_bpf(sk, BPF_SOCK_OPS_ACTIVE/PASSIVE_ESTABLISHED_CB);
              tcp_init_congestion_control(sk);
              tcp_init_buffer_space(sk);
      This sequence is the same as the (1) active case. We pick this sequence
      because this order correctly allows BPF to override the settings
      including congestion control module and initial cwnd, etc from
      the route, and then allows the CC module to see those settings.
      Suggested-by: NNeal Cardwell <ncardwell@google.com>
      Tested-by: NNeal Cardwell <ncardwell@google.com>
      Signed-off-by: NWei Wang <weiwan@google.com>
      Acked-by: NNeal Cardwell <ncardwell@google.com>
      Acked-by: NYuchung Cheng <ycheng@google.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      27204aaa
  10. 02 10月, 2017 3 次提交
  11. 01 10月, 2017 1 次提交
  12. 20 9月, 2017 1 次提交
    • E
      net: sk_buff rbnode reorg · bffa72cf
      Eric Dumazet 提交于
      skb->rbnode shares space with skb->next, skb->prev and skb->tstamp
      
      Current uses (TCP receive ofo queue and netem) need to save/restore
      tstamp, while skb->dev is either NULL (TCP) or a constant for a given
      queue (netem).
      
      Since we plan using an RB tree for TCP retransmit queue to speedup SACK
      processing with large BDP, this patch exchanges skb->dev and
      skb->tstamp.
      
      This saves some overhead in both TCP and netem.
      
      v2: removes the swtstamp field from struct tcp_skb_cb
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Soheil Hassas Yeganeh <soheil@google.com>
      Cc: Wei Wang <weiwan@google.com>
      Cc: Willem de Bruijn <willemb@google.com>
      Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bffa72cf
  13. 19 9月, 2017 1 次提交
  14. 31 8月, 2017 2 次提交
  15. 26 8月, 2017 1 次提交
    • S
      tcp: fix refcnt leak with ebpf congestion control · ebfa00c5
      Sabrina Dubroca 提交于
      There are a few bugs around refcnt handling in the new BPF congestion
      control setsockopt:
      
       - The new ca is assigned to icsk->icsk_ca_ops even in the case where we
         cannot get a reference on it. This would lead to a use after free,
         since that ca is going away soon.
      
       - Changing the congestion control case doesn't release the refcnt on
         the previous ca.
      
       - In the reinit case, we first leak a reference on the old ca, then we
         call tcp_reinit_congestion_control on the ca that we have just
         assigned, leading to deinitializing the wrong ca (->release of the
         new ca on the old ca's data) and releasing the refcount on the ca
         that we actually want to use.
      
      This is visible by building (for example) BIC as a module and setting
      net.ipv4.tcp_congestion_control=bic, and using tcp_cong_kern.c from
      samples/bpf.
      
      This patch fixes the refcount issues, and moves reinit back into tcp
      core to avoid passing a ca pointer back to BPF.
      
      Fixes: 91b5b21c ("bpf: Add support for changing congestion control")
      Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
      Acked-by: NLawrence Brakmo <brakmo@fb.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ebfa00c5
  16. 24 8月, 2017 1 次提交
    • M
      tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg · 98aaa913
      Mike Maloney 提交于
      When SOF_TIMESTAMPING_RX_SOFTWARE is enabled for tcp sockets, return the
      timestamp corresponding to the highest sequence number data returned.
      
      Previously the skb->tstamp is overwritten when a TCP packet is placed
      in the out of order queue.  While the packet is in the ooo queue, save the
      timestamp in the TCB_SKB_CB.  This space is shared with the gso_*
      options which are only used on the tx path, and a previously unused 4
      byte hole.
      
      When skbs are coalesced either in the sk_receive_queue or the
      out_of_order_queue always choose the timestamp of the appended skb to
      maintain the invariant of returning the timestamp of the last byte in
      the recvmsg buffer.
      Signed-off-by: NMike Maloney <maloney@google.com>
      Acked-by: NWillem de Bruijn <willemb@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      98aaa913
  17. 23 8月, 2017 1 次提交