An issue was discovered in the Linux kernel before 5.1.8. There is a NULL pointer dereference caused by a malicious USB device in the sound/usb/line6/driver.c driver.
https://usn.ubuntu.com/4147-1/
https://syzkaller.appspot.com/bug?id=0c1e517c657d3de2361cb0cc2d3a8663c25039a7
https://security.netapp.com/advisory/ntap-20190905-0002/
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.1.8