[Bug 231859] ipoib datagram mode: unicast packets are received as multicast packets

Mon Oct 1 16:34:12 UTC 2018

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=231859

            Bug ID: 231859
           Summary: ipoib datagram mode: unicast packets are received as
                    multicast packets
           Product: Base System
           Version: 11.2-RELEASE
          Hardware: amd64
                OS: Any
            Status: New
          Severity: Affects Some People
          Priority: ---
         Component: kern
          Assignee: bugs at FreeBSD.org
          Reporter: bmueller at panasas.com

When using the ipoib driver built without IPOIB_CM option, simple commands such
ping do not work.  The problem is packets received by the ipoib driver are
being tagged as M_MCAST.  Higher layers in the network stack process the packet
as a multicast packet and may ignore it.  In the case of 'ping <IB host>', ICMP
will not respond unless the net.inet.icmp.bmcastecho sysctl is set to 0.

Adding debugging to ipoib_input(), the received packet has the following
hwaddr: 0:ff:ff:ff:ff:12:40:1b:ff:ff:0:0:0:0:0:0:ff:ff:ff:ff

The address is a IB multicast address.  When I look at the ibdump output on the
sender, the ICMP ECHO packet looks like a unicast packet sent from source LID
15 to destination LID 2.

Extensible Record Format
    Timestamp: 0x5bb2469255113055
    Record type: 0x15 (Type 21: INFINIBAND)
        .001 0101 = Type: INFINIBAND (21)
        0... .... = Extension header present: 0
    Flags: 0x04 (Capture Interface: 0)
        .... ..00 = Capture interface: 0
        .... .1.. = Varying record length: 1
        .... 0... = Truncated: 0
        ...0 .... = RX error: 0
        ..0. .... = DS error: 0
        00.. .... = Reserved: 0x0
    Record length: 138
    Loss counter: 0
    Wire length: 122
InfiniBand
    Local Route Header
        0000 .... = Virtual Lane: 0x0
        .... 0000 = Link Version: 0
        0000 .... = Service Level: 0
        .... 00.. = Reserved (2 bits): 0
        .... ..10 = Link Next Header: 0x2
        Destination Local ID: 2
        0000 0... .... .... = Reserved (5 bits): 0
        .... .000 0001 1110 = Packet Length: 30
        Source Local ID: 15
    Base Transport Header
        Opcode: Unreliable Datagram (UD) - SEND only (100)
        0... .... = Solicited Event: False
        .1.. .... = MigReq: True
        ..00 .... = Pad Count: 0
        .... 0000 = Header Version: 0
        Partition Key: 65535
        Reserved: 00
        Destination Queue Pair: 0x000228
        0... .... = Acknowledge Request: False
        .000 0000 = Reserved (7 bits): 0
        Packet Sequence Number: 203633
    DETH - Datagram Extended Transport Header
        Queue Key: 0x0000000000000b1b
        Reserved: 00
        Source Queue Pair: 0x00000210
    IBA Payload - appears to be EtherType encapsulated
        Ethertype: IPv4 (0x0800)
        Reserved: 0000
    Invariant CRC: 0x29a166b6
    Variant CRC: 0x39c8
Internet Protocol Version 4, Src: 192.168.1.204, Dst: 192.168.1.116
    0100 .... = Version: 4
    .... 0101 = Header Length: 20 bytes (5)
    Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
        0000 00.. = Differentiated Services Codepoint: Default (0)
        .... ..00 = Explicit Congestion Notification: Not ECN-Capable Transport
(0)
    Total Length: 84
    Identification: 0xd946 (55622)
    Flags: 0x4000, Don't fragment
        0... .... .... .... = Reserved bit: Not set
        .1.. .... .... .... = Don't fragment: Set
        ..0. .... .... .... = More fragments: Not set
        ...0 0000 0000 0000 = Fragment offset: 0
    Time to live: 64
    Protocol: ICMP (1)
    Header checksum: 0xdcd1 [validation disabled]
    [Header checksum status: Unverified]
    Source: 192.168.1.204
    Destination: 192.168.1.116
Internet Control Message Protocol
    Type: 8 (Echo (ping) request)
    Code: 0
    Checksum: 0x1ea9 [correct]
    [Checksum Status: Good]
    Identifier (BE): 10727 (0x29e7)
    Identifier (LE): 59177 (0xe729)
    Sequence number (BE): 1 (0x0001)
    Sequence number (LE): 256 (0x0100)
    Timestamp from icmp data: Oct  1, 2018 16:08:50.000000000 GMT
    [Timestamp from icmp data (relative): 0.332293530 seconds]
    Data (48 bytes)

0000  a7 f9 04 00 00 00 00 00 10 11 12 13 14 15 16 17   ................
0010  18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 24 25 26 27   ........ !"#$%&'
0020  28 29 2a 2b 2c 2d 2e 2f 30 31 32 33 34 35 36 37   ()*+,-./01234567
        Data: a7f9040000000000101112131415161718191a1b1c1d1e1f...
        [Length: 48]

-- 
You are receiving this mail because:
You are the assignee for the bug.