1. 11 2月, 2017 3 次提交
  2. 09 2月, 2017 2 次提交
  3. 08 2月, 2017 5 次提交
  4. 07 2月, 2017 1 次提交
  5. 05 2月, 2017 2 次提交
  6. 04 2月, 2017 2 次提交
  7. 03 2月, 2017 2 次提交
  8. 02 2月, 2017 6 次提交
  9. 31 1月, 2017 2 次提交
  10. 30 1月, 2017 2 次提交
  11. 26 1月, 2017 5 次提交
    • W
      net/tcp-fastopen: make connect()'s return case more consistent with non-TFO · 3979ad7e
      Willy Tarreau 提交于
      Without TFO, any subsequent connect() call after a successful one returns
      -1 EISCONN. The last API update ensured that __inet_stream_connect() can
      return -1 EINPROGRESS in response to sendmsg() when TFO is in use to
      indicate that the connection is now in progress. Unfortunately since this
      function is used both for connect() and sendmsg(), it has the undesired
      side effect of making connect() now return -1 EINPROGRESS as well after
      a successful call, while at the same time poll() returns POLLOUT. This
      can confuse some applications which happen to call connect() and to
      check for -1 EISCONN to ensure the connection is usable, and for which
      EINPROGRESS indicates a need to poll, causing a loop.
      
      This problem was encountered in haproxy where a call to connect() is
      precisely used in certain cases to confirm a connection's readiness.
      While arguably haproxy's behaviour should be improved here, it seems
      important to aim at a more robust behaviour when the goal of the new
      API is to make it easier to implement TFO in existing applications.
      
      This patch simply ensures that we preserve the same semantics as in
      the non-TFO case on the connect() syscall when using TFO, while still
      returning -1 EINPROGRESS on sendmsg(). For this we simply tell
      __inet_stream_connect() whether we're doing a regular connect() or in
      fact connecting for a sendmsg() call.
      
      Cc: Wei Wang <weiwan@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Cc: Eric Dumazet <edumazet@google.com>
      Signed-off-by: NWilly Tarreau <w@1wt.eu>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3979ad7e
    • W
      net/tcp-fastopen: Add new API support · 19f6d3f3
      Wei Wang 提交于
      This patch adds a new socket option, TCP_FASTOPEN_CONNECT, as an
      alternative way to perform Fast Open on the active side (client). Prior
      to this patch, a client needs to replace the connect() call with
      sendto(MSG_FASTOPEN). This can be cumbersome for applications who want
      to use Fast Open: these socket operations are often done in lower layer
      libraries used by many other applications. Changing these libraries
      and/or the socket call sequences are not trivial. A more convenient
      approach is to perform Fast Open by simply enabling a socket option when
      the socket is created w/o changing other socket calls sequence:
        s = socket()
          create a new socket
        setsockopt(s, IPPROTO_TCP, TCP_FASTOPEN_CONNECT …);
          newly introduced sockopt
          If set, new functionality described below will be used.
          Return ENOTSUPP if TFO is not supported or not enabled in the
          kernel.
      
        connect()
          With cookie present, return 0 immediately.
          With no cookie, initiate 3WHS with TFO cookie-request option and
          return -1 with errno = EINPROGRESS.
      
        write()/sendmsg()
          With cookie present, send out SYN with data and return the number of
          bytes buffered.
          With no cookie, and 3WHS not yet completed, return -1 with errno =
          EINPROGRESS.
          No MSG_FASTOPEN flag is needed.
      
        read()
          Return -1 with errno = EWOULDBLOCK/EAGAIN if connect() is called but
          write() is not called yet.
          Return -1 with errno = EWOULDBLOCK/EAGAIN if connection is
          established but no msg is received yet.
          Return number of bytes read if socket is established and there is
          msg received.
      
      The new API simplifies life for applications that always perform a write()
      immediately after a successful connect(). Such applications can now take
      advantage of Fast Open by merely making one new setsockopt() call at the time
      of creating the socket. Nothing else about the application's socket call
      sequence needs to change.
      Signed-off-by: NWei Wang <weiwan@google.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Acked-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      19f6d3f3
    • W
      net/tcp-fastopen: refactor cookie check logic · 065263f4
      Wei Wang 提交于
      Refactor the cookie check logic in tcp_send_syn_data() into a function.
      This function will be called else where in later changes.
      Signed-off-by: NWei Wang <weiwan@google.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Acked-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      065263f4
    • J
      tcp: correct memory barrier usage in tcp_check_space() · 56d80622
      Jason Baron 提交于
      sock_reset_flag() maps to __clear_bit() not the atomic version clear_bit().
      Thus, we need smp_mb(), smp_mb__after_atomic() is not sufficient.
      
      Fixes: 3c715127 ("tcp: add memory barriers to write space paths")
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Signed-off-by: NJason Baron <jbaron@akamai.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Reported-by: NOleg Nesterov <oleg@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      56d80622
    • E
      tcp: reduce skb overhead in selected places · 60b1af33
      Eric Dumazet 提交于
      tcp_add_backlog() can use skb_condense() helper to get better
      gains and less SKB_TRUESIZE() magic. This only happens when socket
      backlog has to be used.
      
      Some attacks involve specially crafted out of order tiny TCP packets,
      clogging the ofo queue of (many) sockets.
      Then later, expensive collapse happens, trying to copy all these skbs
      into single ones.
      This unfortunately does not work if each skb has no neighbor in TCP
      sequence order.
      
      By using skb_condense() if the skb could not be coalesced to a prior
      one, we defeat these kind of threats, potentially saving 4K per skb
      (or more, since this is one page fragment).
      
      A typical NAPI driver allocates gro packets with GRO_MAX_HEAD bytes
      in skb->head, meaning the copy done by skb_condense() is limited to
      about 200 bytes.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      60b1af33
  12. 25 1月, 2017 2 次提交
  13. 21 1月, 2017 2 次提交
  14. 20 1月, 2017 1 次提交
    • A
      tcp: initialize max window for a new fastopen socket · 0dbd7ff3
      Alexey Kodanev 提交于
      Found that if we run LTP netstress test with large MSS (65K),
      the first attempt from server to send data comparable to this
      MSS on fastopen connection will be delayed by the probe timer.
      
      Here is an example:
      
           < S  seq 0:0 win 43690 options [mss 65495 wscale 7 tfo cookie] length 32
           > S. seq 0:0 ack 1 win 43690 options [mss 65495 wscale 7] length 0
           < .  ack 1 win 342 length 0
      
      Inside tcp_sendmsg(), tcp_send_mss() returns max MSS in 'mss_now',
      as well as in 'size_goal'. This results the segment not queued for
      transmition until all the data copied from user buffer. Then, inside
      __tcp_push_pending_frames(), it breaks on send window test and
      continues with the check probe timer.
      
      Fragmentation occurs in tcp_write_wakeup()...
      
      +0.2 > P. seq 1:43777 ack 1 win 342 length 43776
           < .  ack 43777, win 1365 length 0
           > P. seq 43777:65001 ack 1 win 342 options [...] length 21224
           ...
      
      This also contradicts with the fact that we should bound to the half
      of the window if it is large.
      
      Fix this flaw by correctly initializing max_window. Before that, it
      could have large values that affect further calculations of 'size_goal'.
      
      Fixes: 168a8f58 ("tcp: TCP Fast Open Server - main code path")
      Signed-off-by: NAlexey Kodanev <alexey.kodanev@oracle.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0dbd7ff3
  15. 19 1月, 2017 3 次提交
    • D
      lwtunnel: fix autoload of lwt modules · 9ed59592
      David Ahern 提交于
      Trying to add an mpls encap route when the MPLS modules are not loaded
      hangs. For example:
      
          CONFIG_MPLS=y
          CONFIG_NET_MPLS_GSO=m
          CONFIG_MPLS_ROUTING=m
          CONFIG_MPLS_IPTUNNEL=m
      
          $ ip route add 10.10.10.10/32 encap mpls 100 via inet 10.100.1.2
      
      The ip command hangs:
      root       880   826  0 21:25 pts/0    00:00:00 ip route add 10.10.10.10/32 encap mpls 100 via inet 10.100.1.2
      
          $ cat /proc/880/stack
          [<ffffffff81065a9b>] call_usermodehelper_exec+0xd6/0x134
          [<ffffffff81065efc>] __request_module+0x27b/0x30a
          [<ffffffff814542f6>] lwtunnel_build_state+0xe4/0x178
          [<ffffffff814aa1e4>] fib_create_info+0x47f/0xdd4
          [<ffffffff814ae451>] fib_table_insert+0x90/0x41f
          [<ffffffff814a8010>] inet_rtm_newroute+0x4b/0x52
          ...
      
      modprobe is trying to load rtnl-lwt-MPLS:
      
      root       881     5  0 21:25 ?        00:00:00 /sbin/modprobe -q -- rtnl-lwt-MPLS
      
      and it hangs after loading mpls_router:
      
          $ cat /proc/881/stack
          [<ffffffff81441537>] rtnl_lock+0x12/0x14
          [<ffffffff8142ca2a>] register_netdevice_notifier+0x16/0x179
          [<ffffffffa0033025>] mpls_init+0x25/0x1000 [mpls_router]
          [<ffffffff81000471>] do_one_initcall+0x8e/0x13f
          [<ffffffff81119961>] do_init_module+0x5a/0x1e5
          [<ffffffff810bd070>] load_module+0x13bd/0x17d6
          ...
      
      The problem is that lwtunnel_build_state is called with rtnl lock
      held preventing mpls_init from registering.
      
      Given the potential references held by the time lwtunnel_build_state it
      can not drop the rtnl lock to the load module. So, extract the module
      loading code from lwtunnel_build_state into a new function to validate
      the encap type. The new function is called while converting the user
      request into a fib_config which is well before any table, device or
      fib entries are examined.
      
      Fixes: 745041e2 ("lwtunnel: autoload of lwt modules")
      Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      9ed59592
    • A
      netfilter: ipt_CLUSTERIP: fix build error without procfs · 3fd0b634
      Arnd Bergmann 提交于
      We can't access c->pde if CONFIG_PROC_FS is disabled:
      
      net/ipv4/netfilter/ipt_CLUSTERIP.c: In function 'clusterip_config_find_get':
      net/ipv4/netfilter/ipt_CLUSTERIP.c:147:9: error: 'struct clusterip_config' has no member named 'pde'
      
      This moves the check inside of another #ifdef.
      
      Fixes: 6c5d5cfb ("netfilter: ipt_CLUSTERIP: check duplicate config when initializing")
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      3fd0b634
    • J
      inet: reset tb->fastreuseport when adding a reuseport sk · 637bc8bb
      Josef Bacik 提交于
      If we have non reuseport sockets on a tb we will set tb->fastreuseport to 0 and
      never set it again.  Which means that in the future if we end up adding a bunch
      of reuseport sk's to that tb we'll have to do the expensive scan every time.
      Instead add the ipv4/ipv6 saddr fields to the bind bucket, as well as the family
      so we know what comparison to make, and the ipv6 only setting so we can make
      sure to compare with new sockets appropriately.  Once one sk has made it onto
      the list we know that there are no potential bind conflicts on the owners list
      that match that sk's rcv_addr.  So copy the sk's information into our bind
      bucket and set tb->fastruseport to FASTREUSESOCK_STRICT so we know we have to do
      an extra check for subsequent reuseport sockets and skip the expensive bind
      conflict check.
      Signed-off-by: NJosef Bacik <jbacik@fb.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      637bc8bb