Re: pcap of misbehaving fallocate over cifs rdma

[David Howells <dhowells@redhat.com>]

Tom Talpey <tom@talpey.com> wrote:

> That's a really large SMBDirect Send operation, it looks like it's
> trying to send the entire write in one message and it overflows
> the receive buffer.
> 
> I'm still fighting with wireshark and can't decode the layers
> above TCP. Can you look at the SMBDirect negotiation at the
> start of the trace, and tell me what the max send/receive
> values were set by each side?

Frame 8: 110 bytes on wire (880 bits), 110 bytes captured (880 bits) on interface enp2s0, id 0
Ethernet II, Src: IntelCor_bb:e6:30 (00:1b:21:bb:e6:30), Dst: IntelCor_bb:e6:ac (00:1b:21:bb:e6:ac)
Internet Protocol Version 4, Src: 192.168.6.2, Dst: 192.168.6.1
Transmission Control Protocol, Src Port: 50018, Dst Port: 5445, Seq: 33, Ack: 33, Len: 44
iWARP Marker Protocol data unit Aligned framing
iWARP Direct Data Placement and Remote Direct Memory Access Protocol
SMB-Direct (SMB RDMA Transport)
    NegotiateRequest
        MinVersion: 0x0100
        MaxVersion: 0x0100
        CreditsRequested: 255
        PreferredSendSize: 1364
        MaxReceiveSize: 1364
        MaxFragmentedSize: 1048576

Frame 9: 122 bytes on wire (976 bits), 122 bytes captured (976 bits) on interface enp2s0, id 0
Ethernet II, Src: IntelCor_bb:e6:ac (00:1b:21:bb:e6:ac), Dst: IntelCor_bb:e6:30 (00:1b:21:bb:e6:30)
Internet Protocol Version 4, Src: 192.168.6.1, Dst: 192.168.6.2
Transmission Control Protocol, Src Port: 5445, Dst Port: 50018, Seq: 33, Ack: 77, Len: 56
iWARP Marker Protocol data unit Aligned framing
iWARP Direct Data Placement and Remote Direct Memory Access Protocol
SMB-Direct (SMB RDMA Transport)
    NegotiateResponse
        MinVersion: 0x0100
        MaxVersion: 0x0100
        NegotiatedVersion: 0x0100
        CreditsRequested: 255
        CreditsGranted: 254
        Status: STATUS_SUCCESS (0x00000000)
        MaxReadWriteSize: 524224
        PreferredSendSize: 1364
        MaxReceiveSize: 1364
        MaxFragmentedSize: 173910

Frame 10: 110 bytes on wire (880 bits), 110 bytes captured (880 bits) on interface enp2s0, id 0
Ethernet II, Src: IntelCor_bb:e6:30 (00:1b:21:bb:e6:30), Dst: IntelCor_bb:e6:ac (00:1b:21:bb:e6:ac)
Internet Protocol Version 4, Src: 192.168.6.2, Dst: 192.168.6.1
Transmission Control Protocol, Src Port: 50018, Dst Port: 5445, Seq: 77, Ack: 89, Len: 44
iWARP Marker Protocol data unit Aligned framing
iWARP Direct Data Placement and Remote Direct Memory Access Protocol
SMB-Direct (SMB RDMA Transport)
    DataMessage
        CreditsRequested: 255
        CreditsGranted: 255
        Flags: 0x0000
            .... .... .... ...0 = ResponseRequested: False
        RemainingLength: 0
        DataOffset: 0
        DataLength: 0

Frame 11: 346 bytes on wire (2768 bits), 346 bytes captured (2768 bits) on interface enp2s0, id 0
Ethernet II, Src: IntelCor_bb:e6:30 (00:1b:21:bb:e6:30), Dst: IntelCor_bb:e6:ac (00:1b:21:bb:e6:ac)
Internet Protocol Version 4, Src: 192.168.6.2, Dst: 192.168.6.1
Transmission Control Protocol, Src Port: 50018, Dst Port: 5445, Seq: 121, Ack: 89, Len: 280
iWARP Marker Protocol data unit Aligned framing
iWARP Direct Data Placement and Remote Direct Memory Access Protocol
SMB-Direct (SMB RDMA Transport)
    DataMessage
        CreditsRequested: 255
        CreditsGranted: 0
        Flags: 0x0000
            .... .... .... ...0 = ResponseRequested: False
        RemainingLength: 0
        DataOffset: 24
        DataLength: 232
SMB2 (Server Message Block Protocol version 2)
    SMB2 Header
        ProtocolId: 0xfe534d42
        Header Length: 64
        Credit Charge: 0
        Channel Sequence: 0
        Reserved: 0000
        Command: Negotiate Protocol (0)
        Credits requested: 10
        Flags: 0x00000000
        Chain Offset: 0x00000000
        Message ID: 0
        Process Id: 0x000013c5
        Tree Id: 0x00000000
        Session Id: 0x0000000000000000
        Signature: 00000000000000000000000000000000
        [Response in: 13]
    Negotiate Protocol Request (0x00)
        [Preauth Hash: 81cd52dea94ed363a171b7effe222c0003574f5c54f6c7a1cbb041676ea9ddf15245b2a4…]
        StructureSize: 0x0024
        Dialect count: 4
        Security mode: 0x01, Signing enabled
        Reserved: 0000
        Capabilities: 0x00000077, DFS, LEASING, LARGE MTU, PERSISTENT HANDLES, DIRECTORY LEASING, ENCRYPTION
        Client Guid: c494649a-e636-d94c-a55e-be00d5a02a30
        NegotiateContextOffset: 0x00000070
        NegotiateContextCount: 4
        Reserved: 0000
        Dialect: SMB 2.1 (0x0210)
        Dialect: SMB 3.0 (0x0300)
        Dialect: SMB 3.0.2 (0x0302)
        Dialect: SMB 3.1.1 (0x0311)
        Negotiate Context: SMB2_PREAUTH_INTEGRITY_CAPABILITIES 
            Type: SMB2_PREAUTH_INTEGRITY_CAPABILITIES (0x0001)
            DataLength: 38
            Reserved: 00000000
            HashAlgorithmCount: 1
            SaltLength: 32
            HashAlgorithm: SHA-512 (0x0001)
            Salt: 1d6e14b44264b6cc1db622478c3826c4cd09df1dc70abf73f13b9261724d4181
        Negotiate Context: SMB2_ENCRYPTION_CAPABILITIES 
            Type: SMB2_ENCRYPTION_CAPABILITIES (0x0002)
            DataLength: 8
            Reserved: 00000000
            CipherCount: 3
            CipherId: AES-128-GCM (0x0002)
            CipherId: AES-256-GCM (0x0004)
            CipherId: AES-128-CCM (0x0001)
        Negotiate Context: SMB2_NETNAME_NEGOTIATE_CONTEXT_ID 
            Type: SMB2_NETNAME_NEGOTIATE_CONTEXT_ID (0x0005)
            DataLength: 22
            Reserved: 00000000
            Netname: 192.168.6.1
        Negotiate Context: SMB2_POSIX_EXTENSIONS_CAPABILITIES 
            Type: SMB2_POSIX_EXTENSIONS_CAPABILITIES (0x0100)
            DataLength: 16
            Reserved: 00000000
            POSIX Reserved: 93ad25509cb411e7b42383de968bcd7c