CVE-2025-68191

In the Linux kernel, the following vulnerability has been resolved:

udp_tunnel: use netdev_warn() instead of netdev_WARN()

netdev_WARN() uses WARN/WARN_ON to print a backtrace along with
file and line information. In this case, udp_tunnel_nic_register()
returning an error is just a failed operation, not a kernel bug.

udp_tunnel_nic_register() can fail due to a memory allocation
failure (kzalloc() or udp_tunnel_nic_alloc()).
This is a normal runtime error and not a kernel bug.

Replace netdev_WARN() with netdev_warn() accordingly.