On Thu, Aug 15, 2019 at 11:55 AM Oliver Neukum <oneukum@xxxxxxxx> wrote: > > Am Mittwoch, den 14.08.2019, 16:59 +0100 schrieb Jonathan Bell: > > As reported by one of our users here: > > https://github.com/raspberrypi/linux/issues/3148 > > > > There is a bug when the dwc2 core receives USB data packets that are > > between 1 and 4 bytes in length - 4 bytes are always written to memory > > where the non-packet bytes are garbage. > > Hi, > > in which function does that happen? If your buffer cannot handle 4 > bytes I cannot see how it copes with teh DMA rules. > In drivers/media/usb/uvc/uvc_ctrl.c:uvc_ctrl_populate_cache() and friends. The UVC driver passes in offsets into a struct uvc_control as the "buffer" that usb_control_msg() fills.