1. 30 Jun, 2008 1 commit
    • Jozsef Kadlecsik's avatar
      netfilter: nf_conntrack_tcp: fixing to check the lower bound of valid ACK · 84ebe1cd
      Jozsef Kadlecsik authored
      Lost connections was reported by Thomas Bätzler (running 2.6.25 kernel) on
      the netfilter mailing list (see the thread "Weird nat/conntrack Problem
      with PASV FTP upload"). He provided tcpdump recordings which helped to
      find a long lingering bug in conntrack.
      
      In TCP connection tracking, checking the lower bound of valid ACK could
      lead to mark valid packets as INVALID because:
      
       - We have got a "higher or equal" inequality, but the test checked
         the "higher" condition only; fixed.
       - If the packet contains a SACK option, it could occur that the ACK
         value was before the left edge of our (S)ACK "window": if a previous
         packet from the other party intersected the right edge of the window
         of the receiver, we could move forward the window parameters beyond
         accepting a valid ack. Therefore in this patch we check the rightmost
         SACK edge instead of the ACK value in the lower bound of valid (S)ACK
         test.
      Signed-off-by: default avatarJozsef Kadlecsik <kadlec@blackhole.kfki.hu>
      Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      84ebe1cd
  2. 28 Jun, 2008 15 commits
  3. 27 Jun, 2008 21 commits
  4. 25 Jun, 2008 3 commits