// SPDX-License-Identifier: GPL-2.0 #include <linux/bpf.h> #include <bpf/bpf_helpers.h> SEC("xdp") int _xdp_adjust_tail_grow(struct xdp_md *xdp) { void *data_end = (void *)(long)xdp->data_end; void *data = (void *)(long)xdp->data; int data_len = bpf_xdp_get_buff_len(xdp); int offset = 0; /* Data length determine test case */ if (data_len == 54) { /* sizeof(pkt_v4) */ offset = 4096; /* test too large offset */ } else if (data_len == 74) { /* sizeof(pkt_v6) */ offset = 40; } else if (data_len == 64) { offset = 128; } else if (data_len == 128) { /* Max tail grow 3520 */ offset = 4096 - 256 - 320 - data_len; } else if (data_len == 9000) { offset = 10; } else if (data_len == 9001) { offset = 4096; } else { return XDP_ABORTED; /* No matching test */ } if (bpf_xdp_adjust_tail(xdp, offset)) return XDP_DROP; return XDP_TX; } char _license[] SEC("license") = "GPL";