1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/bpf.h> 4 #include <bpf/bpf_helpers.h> 5 6 __noinline 7 long changes_pkt_data(struct __sk_buff *sk, __u32 len) 8 { 9 return bpf_skb_pull_data(sk, len); 10 } 11 12 __noinline __weak 13 long does_not_change_pkt_data(struct __sk_buff *sk, __u32 len) 14 { 15 return 0; 16 } 17 18 SEC("tc") 19 int dummy(struct __sk_buff *sk) 20 { 21 changes_pkt_data(sk, 0); 22 does_not_change_pkt_data(sk, 0); 23 return 0; 24 } 25 26 char _license[] SEC("license") = "GPL"; 27