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  1. Jan 14, 2014
    • Hannes Frederic Sowa's avatar
      ipv4: introduce hardened ip_no_pmtu_disc mode · 8ed1dc44
      Hannes Frederic Sowa authored
      
      This new ip_no_pmtu_disc mode only allowes fragmentation-needed errors
      to be honored by protocols which do more stringent validation on the
      ICMP's packet payload. This knob is useful for people who e.g. want to
      run an unmodified DNS server in a namespace where they need to use pmtu
      for TCP connections (as they are used for zone transfers or fallback
      for requests) but don't want to use possibly spoofed UDP pmtu information.
      
      Currently the whitelisted protocols are TCP, SCTP and DCCP as they check
      if the returned packet is in the window or if the association is valid.
      
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: John Heffner <johnwheffner@gmail.com>
      Suggested-by: default avatarFlorian Weimer <fweimer@redhat.com>
      Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8ed1dc44
    • Hannes Frederic Sowa's avatar
      ipv6: introduce ip6_dst_mtu_forward and protect forwarding path with it · 0954cf9c
      Hannes Frederic Sowa authored
      
      In the IPv6 forwarding path we are only concerend about the outgoing
      interface MTU, but also respect locked MTUs on routes. Tunnel provider
      or IPSEC already have to recheck and if needed send PtB notifications
      to the sending host in case the data does not fit into the packet with
      added headers (we only know the final header sizes there, while also
      using path MTU information).
      
      The reason for this change is, that path MTU information can be injected
      into the kernel via e.g. icmp_err protocol handler without verification
      of local sockets. As such, this could cause the IPv6 forwarding path to
      wrongfully emit Packet-too-Big errors and drop IPv6 packets.
      
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: John Heffner <johnwheffner@gmail.com>
      Cc: Steffen Klassert <steffen.klassert@secunet.com>
      Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0954cf9c
    • Hannes Frederic Sowa's avatar
      ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing · f87c10a8
      Hannes Frederic Sowa authored
      
      While forwarding we should not use the protocol path mtu to calculate
      the mtu for a forwarded packet but instead use the interface mtu.
      
      We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was
      introduced for multicast forwarding. But as it does not conflict with
      our usage in unicast code path it is perfect for reuse.
      
      I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu
      along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular
      dependencies because of IPSKB_FORWARDED.
      
      Because someone might have written a software which does probe
      destinations manually and expects the kernel to honour those path mtus
      I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone
      can disable this new behaviour. We also still use mtus which are locked on a
      route for forwarding.
      
      The reason for this change is, that path mtus information can be injected
      into the kernel via e.g. icmp_err protocol handler without verification
      of local sockets. As such, this could cause the IPv4 forwarding path to
      wrongfully emit fragmentation needed notifications or start to fragment
      packets along a path.
      
      Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED
      won't be set and further fragmentation logic will use the path mtu to
      determine the fragmentation size. They also recheck packet size with
      help of path mtu discovery and report appropriate errors.
      
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: John Heffner <johnwheffner@gmail.com>
      Cc: Steffen Klassert <steffen.klassert@secunet.com>
      Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f87c10a8
    • Terry Lam's avatar
      HHF qdisc: fix jiffies-time conversion. · 6c76a07a
      Terry Lam authored
      
      This is to be compatible with the use of "get_time" (i.e. default
      time unit in us) in iproute2 patch for HHF as requested by Stephen.
      
      Signed-off-by: default avatarTerry Lam <vtlam@google.com>
      Acked-by: default avatarNandita Dukkipati <nanditad@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6c76a07a
    • Joe Perches's avatar
      qlcnic: Convert vmalloc/memset to kcalloc · f3c0773f
      Joe Perches authored
      
      vmalloc is a limited resource.  Don't use it unnecessarily.
      
      It seems this allocation should work with kcalloc.
      
      Remove unnecessary memset(,0,) of buf as it's completely
      overwritten as the previously only unset field in
      struct qlcnic_pci_func_cfg is now set to 0.
      
      Use kfree instead of vfree.
      Use ETH_ALEN instead of 6.
      
      Signed-off-by: default avatarJoe Perches <joe@perches.com>
      Acked-by: default avatarJitendra Kalsaria <jitendra.kalsaria@qlogic.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f3c0773f
  2. Jan 13, 2014
  3. Jan 12, 2014
  4. Jan 11, 2014