In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtk_ppe: 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->netdev[0] will be NULL but the code will directly try to access netdev_ops. Instead of just checking for the first net_device, it must be checked if any of the mtk_eth net_devices is matching the netdev_ops of the ingress device.
https://git.kernel.org/stable/c/976ff48c2ac6e6b25b01428c9d7997bcd0fb2949
https://git.kernel.org/stable/c/7b2380f0a0e374010c1a4a13203511b9dee5b166
https://git.kernel.org/stable/c/5dff799c677152dde963c3917bacd9127b03e145
https://git.kernel.org/stable/c/0b832aad33e6f160fda310f0306a6483d85e9d6e