[bpf,v4,0/2] bpf: Fix l3 to l2 use of bpf_skb_change_head

Message

Jussi Maki May 19, 2021, 3:47 p.m. UTC

This fixes an issue with using bpf_skb_change_head to redirect
packet from l3 to l2 device. See commit messages for details.

v3->v4:
- Run the tc_redirect test in its own thread to isolate the network and
  mount namespace modifications to the test thread. Fixes the failing CI
  check in v3.

v2->v3:
- Refactor test_tc_redirect_peer_l3 to use BPF for passing packets
  to both directions instead of relying on forwarding on the way back.
- Clean up of tc_redirect test. Setup and tear down namespaces for each
  test case and avoid a more complex cleanup when tearing down the
  namespace is enough.

v1->v2:
- Port the test case to the newly refactored prog_tests/tc_redirect.c.