Re: ftdi_sio BUG: NULL pointer dereference

[Mike Remski <mremski@mutualink.net>]

On 06/02/2014 11:40 AM, Johan Hovold wrote:
> [ Please avoid top-posting. ]
>
> On Mon, Jun 02, 2014 at 11:16:11AM -0400, Mike Remski wrote:
>> Thanks Johan, that's why I looked at the cross references for ftdi_sio.c
>> over on
>> http://lxr.free-electrons.com/source/drivers/usb/serial/ftdi_sio.c,
>> latest version it's showing is 3.14.  It appears that the ftdi_sio code
>> is largely the same as in 2.6.32, particularly in the
>> ftdi_set_max_packet_size() function.
> Lots of things have changed since v2.6.32 and not just in the driver
> itself but in all the infrastructure it relies on.
>
>> I'm trying to verify if the "number of endpoints is 0" is a valid
>> situation.
> No, that is not normal, but it should not crash the driver if it's a
> hardware issue. What is the lsusb -v output of your device (make sure
> the ftdi_sio driver isn't loaded when connecting the device).
>
> And what happens if you plug it into a machine running a recent kernel?
>
> Thanks,
> Johan
Thanks Johan;  sorry for top posting.
An even more ancient kernel (2.6.18) has v1.4.3 of the ftdi_sio.c and I 
do not see this problem.  In v1.4.3,
ftdi_sio_attach() is doing the work that is now in 
ftdi_sio_port_probe(), but 1.4.3 does not have the 
ftdi_set_max_packet_size() code.  The device works fine under 2.6.18.  I 
have to see if I can scrounge up
a machine running a later kernel (other than my desktop).
Should have included this earlier but its unmodified CentOs 6.0 and 6.4, 
kernel is:

Linux nicA91A84 2.6.32-71.29.1.el6.i686 #1 SMP Tue May 10 17:35:05 CDT 
2011 i686 i686 i386 GNU/Linux


lsusb -v cut for the device in question.

Bus 005 Device 003: ID 1fdf:1001
Device Descriptor:
   bLength                18
   bDescriptorType         1
   bcdUSB               2.00
   bDeviceClass          239 Miscellaneous Device
   bDeviceSubClass         2 ?
   bDeviceProtocol         1 Interface Association
   bMaxPacketSize0        64
   idVendor           0x1fdf
   idProduct          0x1001
   bcdDevice            0.03
   iManufacturer           1 Sepura
   iProduct                2 Colour Console
   iSerial                 0
   bNumConfigurations      1
   Configuration Descriptor:
     bLength                 9
     bDescriptorType         2
     wTotalLength          134
     bNumInterfaces          4
     bConfigurationValue     1
     iConfiguration          0
     bmAttributes         0xc0
       Self Powered
     MaxPower              100mA
     Interface Association:
       bLength                 8
       bDescriptorType        11
       bFirstInterface         0
       bInterfaceCount         2
       bFunctionClass          2 Communications
       bFunctionSubClass       2 Abstract (modem)
       bFunctionProtocol       0 None
       iFunction               0
     Interface Descriptor:
       bLength                 9
       bDescriptorType         4
       bInterfaceNumber        0
       bAlternateSetting       0
       bNumEndpoints           1
       bInterfaceClass         2 Communications
       bInterfaceSubClass      2 Abstract (modem)
       bInterfaceProtocol      0 None
       iInterface              0
       CDC Header:
         bcdCDC               1.10
       CDC Call Management:
         bmCapabilities       0x01
           call management
         bDataInterface          1
       CDC ACM:
         bmCapabilities       0x02
           line coding and serial state
       CDC Union:
         bMasterInterface        0
         bSlaveInterface         1
       Endpoint Descriptor:
         bLength                 7
         bDescriptorType         5
         bEndpointAddress     0x83  EP 3 IN
         bmAttributes            3
           Transfer Type            Interrupt
           Synch Type               None
           Usage Type               Data
         wMaxPacketSize     0x0040  1x 64 bytes
         bInterval              10
     Interface Descriptor:
       bLength                 9
       bDescriptorType         4
       bInterfaceNumber        1
       bAlternateSetting       0
       bNumEndpoints           2
       bInterfaceClass        10 CDC Data
       bInterfaceSubClass      0 Unused
       bInterfaceProtocol      0
       iInterface              0
       Endpoint Descriptor:
         bLength                 7
         bDescriptorType         5
         bEndpointAddress     0x01  EP 1 OUT
         bmAttributes            2
           Transfer Type            Bulk
           Synch Type               None
           Usage Type               Data
         wMaxPacketSize     0x0040  1x 64 bytes
         bInterval               0
       Endpoint Descriptor:
         bLength                 7
         bDescriptorType         5
         bEndpointAddress     0x82  EP 2 IN
         bmAttributes            2
           Transfer Type            Bulk
           Synch Type               None
           Usage Type               Data
         wMaxPacketSize     0x0040  1x 64 bytes
         bInterval               0
     Interface Association:
       bLength                 8
       bDescriptorType        11
       bFirstInterface         2
       bInterfaceCount         2
       bFunctionClass          2 Communications
       bFunctionSubClass       2 Abstract (modem)
       bFunctionProtocol       0 None
       iFunction               0
     Interface Descriptor:
       bLength                 9
       bDescriptorType         4
       bInterfaceNumber        2
       bAlternateSetting       0
       bNumEndpoints           0
       bInterfaceClass         2 Communications
       bInterfaceSubClass      2 Abstract (modem)
       bInterfaceProtocol      0 None
       iInterface              0
       CDC Header:
         bcdCDC               1.10
       CDC Call Management:
         bmCapabilities       0x01
           call management
         bDataInterface          3
       CDC ACM:
         bmCapabilities       0x02
           line coding and serial state
       CDC Union:
         bMasterInterface        2
         bSlaveInterface         3
     Interface Descriptor:
       bLength                 9
       bDescriptorType         4
       bInterfaceNumber        3
       bAlternateSetting       0
       bNumEndpoints           2
       bInterfaceClass        10 CDC Data
       bInterfaceSubClass      0 Unused
       bInterfaceProtocol      0
       iInterface              0
       Endpoint Descriptor:
         bLength                 7
         bDescriptorType         5
         bEndpointAddress     0x04  EP 4 OUT
         bmAttributes            2
           Transfer Type            Bulk
           Synch Type               None
           Usage Type               Data
         wMaxPacketSize     0x0040  1x 64 bytes
         bInterval               0
       Endpoint Descriptor:
         bLength                 7
         bDescriptorType         5
         bEndpointAddress     0x85  EP 5 IN
         bmAttributes            2
           Transfer Type            Bulk
           Synch Type               None
           Usage Type               Data
         wMaxPacketSize     0x0040  1x 64 bytes
         bInterval               0
Device Status:     0x0001
   Self Powered

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