[PATCH 2/2] selftest/hid: add test for negative return codes for hid_bpf_hw_request

[Benjamin Tissoires <bentiss@kernel.org>]

If the transport driver returns an error, we should ensure we actually
get the error, not a success value.

Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
---
 tools/testing/selftests/hid/hid_bpf.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/tools/testing/selftests/hid/hid_bpf.c b/tools/testing/selftests/hid/hid_bpf.c
index 32d81ba15a25..8c41ebfb85e4 100644
--- a/tools/testing/selftests/hid/hid_bpf.c
+++ b/tools/testing/selftests/hid/hid_bpf.c
@@ -546,6 +546,37 @@ TEST_F(hid_bpf, test_hid_user_raw_request_call)
 	ASSERT_EQ(args.data[1], 2);
 }
 
+/*
+ * Call hid_hw_raw_request against the given uhid device,
+ * check that the program is called and does the expected.
+ */
+TEST_F(hid_bpf, test_hid_user_raw_request_call_eio)
+{
+	struct hid_hw_request_syscall_args args = {
+		.retval = -1,
+		.type = HID_FEATURE_REPORT,
+		.request_type = HID_REQ_GET_PROTOCOL,
+		.size = MAX_BUF_SIZE,
+	};
+	DECLARE_LIBBPF_OPTS(bpf_test_run_opts, tattrs,
+			    .ctx_in = &args,
+			    .ctx_size_in = sizeof(args),
+	);
+	int err, prog_fd;
+
+	LOAD_BPF;
+
+	args.hid = self->hid.hid_id;
+	args.data[0] = 1; /* report ID */
+
+	prog_fd = bpf_program__fd(self->skel->progs.hid_user_raw_request);
+
+	err = bpf_prog_test_run_opts(prog_fd, &tattrs);
+	ASSERT_OK(err) TH_LOG("error while calling bpf_prog_test_run_opts");
+
+	ASSERT_EQ(args.retval, -EIO);
+}
+
 /*
  * Call hid_hw_raw_request against the given uhid device,
  * check that the program is called and prevents the

-- 
2.55.0