On Thu, Apr 03, 2014 at 08:49:40AM +0200, Rafał Miłecki wrote: > I recently wanted to use my ZTE MF636 modem 19d2:0031 and got NULL > pointer dereference in usb_wwan_write few seconds after plugging it. > This is 100% reproducible. > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 > IP: [<ffffffffa07b9570>] usb_wwan_write+0xa0/0x2b0 [usb_wwan] > > I've bisected between 3.4 and 3.14 kernels and it has appeared to be a > regression caused by: > > commit 8e493ca1767d4951ed1322abaa74d6edbca29918 > Author: Johan Hovold <jhovold@xxxxxxxxx> > Date: Fri Oct 26 18:44:20 2012 +0200 > > USB: usb_wwan: fix bulk-urb allocation > > Make sure we do not allocate urbs if we do not have a bulk endpoint. > > Legacy code used incorrect assumption to test for bulk endpoints. > > Reverting above patch from the 3.14 release fixes the NULL pointer > dereference for me. > > Could you look into this, please? I can test any debug/fix patches you provide. Thanks for the detailed report. Could you also provide the output of lsusb -vd 19d2:0031 Thanks, Johan -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
