Currently, bpf_lwt_push_ip_encap() does not update skb->transport_header.
When a driver, e.g. ice, reuses the stale skb->transport_header to
offload checksum computation to NIC hardware, VxLAN packets encapsulated
by bpf_lwt_push_encap() helper may be dropped due to incorrect checksum.
Update skb->transport_header in bpf_lwt_push_ip_encap() whenever the
encapsulated packet uses UDP, so checksum offload works correctly.
Leon Hwang (2):
bpf: Update transport_header when encapsulating UDP tunnel in lwt
selftests/bpf: Add tests to verify the fix of encapsulating VxLAN in
lwt
net/core/lwt_bpf.c | 4 +
.../selftests/bpf/prog_tests/lwt_ip_encap.c | 153 ++++++++++++++++++
.../selftests/bpf/progs/test_lwt_ip_encap.c | 112 +++++++++++++
.../bpf/progs/test_lwt_ip_encap_fix.c | 36 +++++
4 files changed, 305 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/test_lwt_ip_encap_fix.c
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2.54.0
