On 08/17/2016 09:45 AM, Johan Hovold wrote: > On Wed, Aug 17, 2016 at 09:37:02AM +0300, Binyamin Sharet wrote: >> Hi >> >> On 08/16/2016 06:04 PM, Johan Hovold wrote: >>> On Tue, Aug 16, 2016 at 10:47:44AM -0400, Alan Stern wrote: >>>> On Tue, 16 Aug 2016, Binyamin Sharet wrote: >>>> >>>>> Kernel version: raspberrypi 4.4.6-v7+ #871 >>>>> Driver source file: drivers/usb/serial/digi_acceleport.c >>>>> Umap2 command line: umap2vsscan -P <PHY> -s 05c5:0002 >>>>> >>>>> After connecting such a device, NULL pointer dereference in the kernel. >>>>> >>>>> Binyamin Sharet >>>>> Cisco, STARE-C >>>>> >>>>> << Attached: 05c5_0002_dmesg.log >> >>>> This looks like a bug in the digi_acceleport driver. digi_startup() >>>> does this: >>>> >>>> serial_priv->ds_oob_port_num = serial->type->num_ports; >>>> serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num]; >>>> >>>> Even without knowing exactly what this is supposed to be doing, one >>>> gets the definite impression that the first line should be: >>>> >>>> serial_priv->ds_oob_port_num = serial->type->num_ports - 1; >>>> >>>> Johan? >>> The out-of-band port is not included in num_ports so that should not be >>> the issue here. The missing sanity checks for the endpoint layout were >>> only recently added by >>> >>> 5a07975ad0a3 ("USB: digi_acceleport: do sanity checking for the >>> number of ports") >>> >>> however, even if it has been included in 4.4-stable since 4.4.7. >>> >>> Binyamin, could you rerun your tests on the latest 4.4-stable kernel to >>> make sure you're not reporting already fixed issues? >> I have retested this issue with ubuntu 16.04, using kernel 4.7-rc2 >> which is the version that I was asked to test with on another issue >> and it was not reproduced. > You should be testing with 4.8-rc2, which is the latest mainline kernel. > > I mentioned latest 4.4-stable because I knew that the fix for this > particular issue had been in 4.4-stable since 4.4.7. > >> In dmesg I see that OOB endpoint is missing, so I might need to >> modify the descriptors a bit and try again. > Great, thanks for confirming that this was likely an oops due to the > missing sanity checks in 4.4.6, which have since been fixed in mainline > as well as backported to the stable trees. > > Just let us know if you find anything else using 4.8-rc2. > > Thanks, > Johan same result on 4.8-rc2 -- Binyamin Sharet, Cisco, STARE-C -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html