test_bpf: fix the dummy skb after dissector changes

Commit d5709f7ab776 ("flow_dissector: For stripped vlan, get vlan
info from skb->vlan_tci") made flow dissector look at vlan_proto
when vlan is present.  Since test_bpf sets skb->vlan_tci to ~0
(including VLAN_TAG_PRESENT) we have to populate skb->vlan_proto.

Fixes false negative on test #24:
test_bpf: #24 LD_PAYLOAD_OFF jited:0 175 ret 0 != 42 FAIL (1 times)

Signed-off-by: Jakub Kicinski <[email protected]>
Reviewed-by: Dinan Gunawardena <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
Acked-by: Alexei Starovoitov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 93f45011a59d01ef017aa2a1a4a68ee6f4060bce..94346b4d8984c5cfa88743be66b1880b929e4a60 100644 (file)
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -5485,6 +5485,7 @@ static struct sk_buff *populate_skb(char *buf, int size)
        skb->hash = SKB_HASH;
        skb->queue_mapping = SKB_QUEUE_MAP;
        skb->vlan_tci = SKB_VLAN_TCI;
+       skb->vlan_proto = htons(ETH_P_IP);
        skb->dev = &dev;
        skb->dev->ifindex = SKB_DEV_IFINDEX;
        skb->dev->type = SKB_DEV_TYPE;