bpf: Align packet data properly in program testing framework.

Make sure we apply NET_IP_ALIGN when reserving headroom for SKB
and XDP test runs, just like a real driver would.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index f946912c8a8109e7e2f66813a84e2dc8de9b8e63..6be41a44d688a44970981fc9c2f1aa35666807fa 100644 (file)
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -100,7 +100,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
        void *data;
        int ret;
 
-       data = bpf_test_init(kattr, size, NET_SKB_PAD,
+       data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN,
                             SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
        if (IS_ERR(data))
                return PTR_ERR(data);
@@ -125,7 +125,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
                return -ENOMEM;
        }
 
-       skb_reserve(skb, NET_SKB_PAD);
+       skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
        __skb_put(skb, size);
        skb->protocol = eth_type_trans(skb, current->nsproxy->net_ns->loopback_dev);
        skb_reset_network_header(skb);
@@ -156,16 +156,16 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
        void *data;
        int ret;
 
-       data = bpf_test_init(kattr, size, XDP_PACKET_HEADROOM, 0);
+       data = bpf_test_init(kattr, size, XDP_PACKET_HEADROOM + NET_IP_ALIGN, 0);
        if (IS_ERR(data))
                return PTR_ERR(data);
 
        xdp.data_hard_start = data;
-       xdp.data = data + XDP_PACKET_HEADROOM;
+       xdp.data = data + XDP_PACKET_HEADROOM + NET_IP_ALIGN;
        xdp.data_end = xdp.data + size;
 
        retval = bpf_test_run(prog, &xdp, repeat, &duration);
-       if (xdp.data != data + XDP_PACKET_HEADROOM)
+       if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN)
                size = xdp.data_end - xdp.data;
        ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration);
        kfree(data);