1. 14 Jun, 2008 1 commit
  2. 12 Jun, 2008 1 commit
    • David S. Miller's avatar
      tcp: Revert 'process defer accept as established' changes. · ec0a1966
      David S. Miller authored
      This reverts two changesets, ec3c0982
      ("[TCP]: TCP_DEFER_ACCEPT updates - process as established") and
      the follow-on bug fix 9ae27e0a
      
      
      ("tcp: Fix slab corruption with ipv6 and tcp6fuzz").
      
      This change causes several problems, first reported by Ingo Molnar
      as a distcc-over-loopback regression where connections were getting
      stuck.
      
      Ilpo Järvinen first spotted the locking problems.  The new function
      added by this code, tcp_defer_accept_check(), only has the
      child socket locked, yet it is modifying state of the parent
      listening socket.
      
      Fixing that is non-trivial at best, because we can't simply just grab
      the parent listening socket lock at this point, because it would
      create an ABBA deadlock.  The normal ordering is parent listening
      socket --> child socket, but this code path would require the
      reverse lock ordering.
      
      Next is a problem noticed by Vitaliy Gusev, he noted:
      
      ----------------------------------------
      >--- a/net/ipv4/tcp_timer.c
      >+++ b/net/ipv4/tcp_timer.c
      >@@ -481,6 +481,11 @@ static void tcp_keepalive_timer (unsigned long data)
      > 		goto death;
      > 	}
      >
      >+	if (tp->defer_tcp_accept.request && sk->sk_state == TCP_ESTABLISHED) {
      >+		tcp_send_active_reset(sk, GFP_ATOMIC);
      >+		goto death;
      
      Here socket sk is not attached to listening socket's request queue. tcp_done()
      will not call inet_csk_destroy_sock() (and tcp_v4_destroy_sock() which should
      release this sk) as socket is not DEAD. Therefore socket sk will be lost for
      freeing.
      ----------------------------------------
      
      Finally, Alexey Kuznetsov argues that there might not even be any
      real value or advantage to these new semantics even if we fix all
      of the bugs:
      
      ----------------------------------------
      Hiding from accept() sockets with only out-of-order data only
      is the only thing which is impossible with old approach. Is this really
      so valuable? My opinion: no, this is nothing but a new loophole
      to consume memory without control.
      ----------------------------------------
      
      So revert this thing for now.
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ec0a1966
  3. 11 Jun, 2008 5 commits
  4. 10 Jun, 2008 1 commit
  5. 02 May, 2008 1 commit
  6. 24 Apr, 2008 1 commit
  7. 14 Apr, 2008 1 commit
  8. 13 Apr, 2008 6 commits
  9. 10 Apr, 2008 1 commit
    • Florian Westphal's avatar
      [Syncookies]: Add support for TCP options via timestamps. · 4dfc2817
      Florian Westphal authored
      
      
      Allow the use of SACK and window scaling when syncookies are used
      and the client supports tcp timestamps. Options are encoded into
      the timestamp sent in the syn-ack and restored from the timestamp
      echo when the ack is received.
      
      Based on earlier work by Glenn Griffin.
      This patch avoids increasing the size of structs by encoding TCP
      options into the least significant bits of the timestamp and
      by not using any 'timestamp offset'.
      
      The downside is that the timestamp sent in the packet after the synack
      will increase by several seconds.
      
      changes since v1:
       don't duplicate timestamp echo decoding function, put it into ipv4/syncookie.c
       and have ipv6/syncookies.c use it.
       Feedback from Glenn Griffin: fix line indented with spaces, kill redundant if ()
      Reviewed-by: default avatarHagen Paul Pfeifer <hagen@jauu.net>
      Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4dfc2817
  10. 03 Apr, 2008 6 commits
  11. 28 Mar, 2008 1 commit
  12. 25 Mar, 2008 3 commits
  13. 24 Mar, 2008 1 commit
  14. 22 Mar, 2008 1 commit
    • Pavel Emelyanov's avatar
      [SOCK]: Add udp_hash member to struct proto. · 39d8cda7
      Pavel Emelyanov authored
      Inspired by the commit ab1e0a13
      
       ([SOCK] proto: Add hashinfo member to 
      struct proto) from Arnaldo, I made similar thing for UDP/-Lite IPv4 
      and -v6 protocols.
      
      The result is not that exciting, but it removes some levels of
      indirection in udpxxx_get_port and saves some space in code and text.
      
      The first step is to union existing hashinfo and new udp_hash on the
      struct proto and give a name to this union, since future initialization 
      of tcpxxx_prot, dccp_vx_protinfo and udpxxx_protinfo will cause gcc 
      warning about inability to initialize anonymous member this way.
      Signed-off-by: default avatarPavel Emelyanov <xemul@openvz.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      39d8cda7
  15. 21 Mar, 2008 4 commits
  16. 05 Mar, 2008 1 commit
  17. 03 Mar, 2008 1 commit
  18. 29 Feb, 2008 2 commits
  19. 17 Feb, 2008 1 commit
  20. 03 Feb, 2008 1 commit
    • Arnaldo Carvalho de Melo's avatar
      [SOCK] proto: Add hashinfo member to struct proto · ab1e0a13
      Arnaldo Carvalho de Melo authored
      
      
      This way we can remove TCP and DCCP specific versions of
      
      sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port
      sk->sk_prot->hash:     inet_hash is directly used, only v6 need
                             a specific version to deal with mapped sockets
      sk->sk_prot->unhash:   both v4 and v6 use inet_hash directly
      
      struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so
      that inet_csk_get_port can find the per family routine.
      
      Now only the lookup routines receive as a parameter a struct inet_hashtable.
      
      With this we further reuse code, reducing the difference among INET transport
      protocols.
      
      Eventually work has to be done on UDP and SCTP to make them share this
      infrastructure and get as a bonus inet_diag interfaces so that iproute can be
      used with these protocols.
      
      net-2.6/net/ipv4/inet_hashtables.c:
        struct proto			     |   +8
        struct inet_connection_sock_af_ops |   +8
       2 structs changed
        __inet_hash_nolisten               |  +18
        __inet_hash                        | -210
        inet_put_port                      |   +8
        inet_bind_bucket_create            |   +1
        __inet_hash_connect                |   -8
       5 functions changed, 27 bytes added, 218 bytes removed, diff: -191
      
      net-2.6/net/core/sock.c:
        proto_seq_show                     |   +3
       1 function changed, 3 bytes added, diff: +3
      
      net-2.6/net/ipv4/inet_connection_sock.c:
        inet_csk_get_port                  |  +15
       1 function changed, 15 bytes added, diff: +15
      
      net-2.6/net/ipv4/tcp.c:
        tcp_set_state                      |   -7
       1 function changed, 7 bytes removed, diff: -7
      
      net-2.6/net/ipv4/tcp_ipv4.c:
        tcp_v4_get_port                    |  -31
        tcp_v4_hash                        |  -48
        tcp_v4_destroy_sock                |   -7
        tcp_v4_syn_recv_sock               |   -2
        tcp_unhash                         | -179
       5 functions changed, 267 bytes removed, diff: -267
      
      net-2.6/net/ipv6/inet6_hashtables.c:
        __inet6_hash |   +8
       1 function changed, 8 bytes added, diff: +8
      
      net-2.6/net/ipv4/inet_hashtables.c:
        inet_unhash                        | +190
        inet_hash                          | +242
       2 functions changed, 432 bytes added, diff: +432
      
      vmlinux:
       16 functions changed, 485 bytes added, 492 bytes removed, diff: -7
      
      /home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c:
        tcp_v6_get_port                    |  -31
        tcp_v6_hash                        |   -7
        tcp_v6_syn_recv_sock               |   -9
       3 functions changed, 47 bytes removed, diff: -47
      
      /home/acme/git/net-2.6/net/dccp/proto.c:
        dccp_destroy_sock                  |   -7
        dccp_unhash                        | -179
        dccp_hash                          |  -49
        dccp_set_state                     |   -7
        dccp_done                          |   +1
       5 functions changed, 1 bytes added, 242 bytes removed, diff: -241
      
      /home/acme/git/net-2.6/net/dccp/ipv4.c:
        dccp_v4_get_port                   |  -31
        dccp_v4_request_recv_sock          |   -2
       2 functions changed, 33 bytes removed, diff: -33
      
      /home/acme/git/net-2.6/net/dccp/ipv6.c:
        dccp_v6_get_port                   |  -31
        dccp_v6_hash                       |   -7
        dccp_v6_request_recv_sock          |   +5
       3 functions changed, 5 bytes added, 38 bytes removed, diff: -33
      Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ab1e0a13