The dvb_frontend_free function in drivers/media/dvb-core/dvb_frontend.c in the Linux kernel through 4.13.11 allows local users to cause a denial of service (use-after-free and system crash) or possibly have unspecified other impact via a crafted USB device. NOTE: the function was later renamed __dvb_frontend_free.
https://patchwork.kernel.org/patch/10046189/
https://groups.google.com/d/msg/syzkaller/0HJQqTm0G_g/T931ItskBAAJ