Add a check to the xdp_link selftest that the kernel rejects replacing an XDP program with a different program type on link update. v2: - Split this out into its own patch. Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> --- tools/testing/selftests/bpf/prog_tests/xdp_link.c | 5 +++++ tools/testing/selftests/bpf/progs/test_xdp_link.c | 6 ++++++ 2 files changed, 11 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_link.c b/tools/testing/selftests/bpf/prog_tests/xdp_link.c index eec0bf83546b..b2b357f8c74c 100644 --- a/tools/testing/selftests/bpf/prog_tests/xdp_link.c +++ b/tools/testing/selftests/bpf/prog_tests/xdp_link.c @@ -127,6 +127,11 @@ void serial_test_xdp_link(void) ASSERT_EQ(link_info.prog_id, id1, "link_prog_id"); ASSERT_EQ(link_info.xdp.ifindex, IFINDEX_LO, "link_ifindex"); + /* updating program under active BPF link with different type fails */ + err = bpf_link__update_program(link, skel1->progs.tc_handler); + if (!ASSERT_ERR(err, "link_upd_invalid")) + goto cleanup; + err = bpf_link__detach(link); if (!ASSERT_OK(err, "link_detach")) goto cleanup; diff --git a/tools/testing/selftests/bpf/progs/test_xdp_link.c b/tools/testing/selftests/bpf/progs/test_xdp_link.c index ee7d6ac0f615..64ff32eaae92 100644 --- a/tools/testing/selftests/bpf/progs/test_xdp_link.c +++ b/tools/testing/selftests/bpf/progs/test_xdp_link.c @@ -10,3 +10,9 @@ int xdp_handler(struct xdp_md *xdp) { return 0; } + +SEC("tc") +int tc_handler(struct __sk_buff *skb) +{ + return 0; +} -- 2.34.1