Re: ftdi_sio BUG: NULL pointer dereference

[Johan Hovold <jhovold@gmail.com>]

On Wed, Jun 04, 2014 at 11:41:47AM -0400, Mike Remski wrote:
> Ok, had a chance to try the cdc-acm;  yes it's the ancient one that is 
> in the base install of CentOS 6.4 (2.6.32-71.29.1 centos patched).  I'm 
> hitting something similar;  I noticed there where a few commits for NULL 
> pointer dereferences in cdc-acm.c.
> 
> I'll poke into this a bit (yes, I know try a newer kernel, etc) and let 
> you know what I find (or perhaps this looks similar to something already 
> seen?).  This device is the same as the original ftdi crash, 1.2 is the 
> same interface with bNumEndpoints == 0.
> 
> Jun  4 11:35:20 nicA91A84 kernel: cdc_acm 5-2:1.2: This device cannot do 
> calls on its own. It is not a modem.
> Jun  4 11:35:20 nicA91A84 kernel: BUG: unable to handle kernel NULL 
> pointer dereference at 00000004
> Jun  4 11:35:20 nicA91A84 kernel: IP: [<f84f9c9e>] 
> acm_probe+0x44e/0x127c [cdc_acm]
> Jun  4 11:35:20 nicA91A84 kernel: *pdpt = 00000000354eb001 *pde = 
> 000000007f003067
> Jun  4 11:35:20 nicA91A84 kernel: Oops: 0000 [#1] SMP
> Jun  4 11:35:20 nicA91A84 kernel: last sysfs file: 
> /sys/devices/pci0000:00/0000:00:1d.0/usb5/5-2/product

Yeah, you really need to update your kernel. You'll definitely need at
least commit 99f347caa456 ("USB: CDC ACM: Fix NULL pointer
dereference").

No more reports until you've tried a recent kernel, ok? ;)

Johan