Turns out that we would en up in a bad state if we attempt to attach twice the same HID-BPF struct_ops, so have a test for it.
Signed-off-by: Benjamin Tissoires bentiss@kernel.org --- tools/testing/selftests/hid/hid_bpf.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)
diff --git a/tools/testing/selftests/hid/hid_bpf.c b/tools/testing/selftests/hid/hid_bpf.c index 9c935fd0dffc..75b7b4ef6cfa 100644 --- a/tools/testing/selftests/hid/hid_bpf.c +++ b/tools/testing/selftests/hid/hid_bpf.c @@ -694,6 +694,24 @@ TEST_F(hid_bpf, subprog_raw_event) ASSERT_EQ(buf[2], 52); }
+/* + * Attach hid_first_event to the given uhid device, + * attempt at re-attaching it, we should not lock and + * return an invalid struct bpf_link + */ +TEST_F(hid_bpf, multiple_attach) +{ + const struct test_program progs[] = { + { .name = "hid_first_event" }, + }; + struct bpf_link *link; + + LOAD_PROGRAMS(progs); + + link = bpf_map__attach_struct_ops(self->skel->maps.first_event); + ASSERT_NULL(link) TH_LOG("unexpected return value when re-attaching the struct_ops"); +} + /* * Ensures that we can attach/detach programs */