A flaw was found in the Linux kernels implementation of Mixer handling. An attacker with physical access can insert a maliciously crafted USB device that can convince the kernels USB mixing hardware to enter a recursive loop which continues to consume the reserved stack space for the thread and panic the system.
As the snd_usb_audio module will be auto-loaded when a usb device is hot plugged, the module can be prevented by loading with the following instructions:
# echo "install snd_usb_audio /bin/true" >> /etc/modprobe.d/disable-snd-usb-audio.conf
The system will need to be restarted if the modules are loaded. In most circumstances, the sound kernel modules will be unable to be unloaded while any programs are active and the device are in use."
If the system requires this module to work correctly, this mitigation may not be suitable.
If you need further assistance, see KCS article https://access.redhat.com/solutions/41278 or contact Red Hat Global Support Services.
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1814084]
This was fixes for Fedora with the 5.2.10 stable kernel updates.