CVE-2022-49776 macvlan: enforce a consistent minimal mtu

In the Linux kernel, the following vulnerability has been resolved: macvlan: enforce a consistent minimal mtu macvlan should enforce a minimal mtu of 68, even at link creation. This patch avoids the current behavior which could lead to crashes in ipv6 stack if the link is brought up $ ip link add...

CVE-2022-49776

CVE-2022-49776 affects the Linux kernel macvlan code; it fixes a low-level issue by enforcing a minimal MTU of 68 at link creation to prevent crashes in the IPv6 stack. The advisory notes that macvlan0 should reject mtu values below the device minimum (e.g., 67 rejected, 68 accepted), with the fi...