selftests/xsk: Verify correctness of XDP prog attach point

To prevent the case we had previously where for TEST_MODE_SKB, XDP prog
was attached in native mode, call bpf_xdp_query() after loading prog and
make sure that attach_mode is as expected.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20220629143458.934337-4-maciej.fijalkowski@intel.com

diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c
index c024aa91ea02623766165d60c95e93c896c5954b..4c425a43e5b00e62c35749dc9f8edb368071e0a3 100644 (file)
--- a/tools/testing/selftests/bpf/xdpxceiver.c
+++ b/tools/testing/selftests/bpf/xdpxceiver.c
@@ -1085,6 +1085,7 @@ static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
 {
        u64 umem_sz = ifobject->umem->num_frames * ifobject->umem->frame_size;
        int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
+       LIBBPF_OPTS(bpf_xdp_query_opts, opts);
        int ret, ifindex;
        void *bufs;
        u32 i;
@@ -1134,6 +1135,22 @@ static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
        if (ret)
                exit_with_error(-ret);
 
+       ret = bpf_xdp_query(ifindex, ifobject->xdp_flags, &opts);
+       if (ret)
+               exit_with_error(-ret);
+
+       if (ifobject->xdp_flags & XDP_FLAGS_SKB_MODE) {
+               if (opts.attach_mode != XDP_ATTACHED_SKB) {
+                       ksft_print_msg("ERROR: [%s] XDP prog not in SKB mode\n");
+                       exit_with_error(-EINVAL);
+               }
+       } else if (ifobject->xdp_flags & XDP_FLAGS_DRV_MODE) {
+               if (opts.attach_mode != XDP_ATTACHED_DRV) {
+                       ksft_print_msg("ERROR: [%s] XDP prog not in DRV mode\n");
+                       exit_with_error(-EINVAL);
+               }
+       }
+
        ret = xsk_socket__update_xskmap(ifobject->xsk->xsk, ifobject->xsk_map_fd);
        if (ret)
                exit_with_error(-ret);