bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb

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

bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb

bpf_prog_test_run_skb() calls eth_type_trans() first and then uses skb->protocol to initialize sk family and address fields for the test run.

For IPv4 and IPv6 packets, it may access ip_hdr(skb) or ipv6_hdr(skb) even when the provided test input only contains an Ethernet header.

Reject the input earlier if the Ethernet frame carries IPv4/IPv6 EtherType but the L3 header is too short.

Fold the IPv4/IPv6 header length checks into the existing protocol switch and return -EINVAL before accessing the network headers.