Hello, 
I'm unsure, what I see.

I use:
Virtual box - Host Win 7/Guest kubuntu 
Linux lisa 3.2.0-30-generic #48-Ubuntu SMP Fri Aug 24 16:52:48 UTC 2012 x86_64 
x86_64 x86_64 GNU/Linux

SocketCAN connector is a EMS CPC-USB.

On startup, the network works fine.
In different situation one or both directions (RX/TX) stop it's work.
My Linux program say:

	write: No buffer space available

It's the write to the socketcan device can0.

For the current situation the communication stopped in general.

$ ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP 
qlen 1000
    link/ether 08:00:27:62:24:48 brd ff:ff:ff:ff:ff:ff
3: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast state UNKNOWN qlen 
100
    link/can 

$ cat /proc/net/can/stats

      717 transmitted frames (TXF)
      820 received frames (RXF)
      607 matched frames (RXMF)

       74 % total match ratio (RXMR)
        0 frames/s total tx rate (TXR)
        0 frames/s total rx rate (RXR)

      100 % current match ratio (CRXMR)
        0 frames/s current tx rate (CTXR)
        0 frames/s current rx rate (CRXR)

      100 % max match ratio (MRXMR)
       11 frames/s max tx rate (MTXR)
       20 frames/s max rx rate (MRXR)

        2 current receive list entries (CRCV)
        2 maximum receive list entries (MRCV)

$ ip -det -stat link show can0
3: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast state UNKNOWN qlen 
100
    link/can 
    can state ERROR-ACTIVE restart-ms 0 
    bitrate 250000 sample-point 0.875 
    tq 250 prop-seg 6 phase-seg1 7 phase-seg2 2 sjw 1
    ems_usb: tseg1 1..16 tseg2 1..8 sjw 1..4 brp 1..64 brp-inc 1
    clock 8000000
    re-started bus-errors arbit-lost error-warn error-pass bus-off
    0          0          0          0          0          0         
    RX: bytes  packets  errors  dropped overrun mcast   
    106        213      0       0       0       0      
    TX: bytes  packets  errors  dropped carrier collsns 
    607        607      0       0       0       0      

$ ./candump any
say nothing

I'm unsure to interprete the data. I cannot see any mistake. 

-- 
Mit freundlichen Grüßen / Best regards
Steffen Rose