CVE-2026-31736 net: ethernet: mtk_ppe: avoid NULL deref when gmac0 is disabled

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtkppe: avoid NULL deref when gmac0 is disabled If the gmac0 is disabled, the precheck for a valid ingress device will cause a NULL pointer deref and crash the system. This happens because eth-netdev0 will be NULL...