[PATCH bpf-next v2 14/28] selftests/bpf: add tests for hid_{get|set}_data helpers

Benjamin Tissoires
2022-03-04T17:33:08Z

Simple test added here, with one use of each helper.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

---

changes in v2:
- split the patch with libbpf left outside.
---
tools/testing/selftests/bpf/prog_tests/hid.c | 65 ++++++++++++++++++++
tools/testing/selftests/bpf/progs/hid.c | 45 ++++++++++++++
2 files changed, 110 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/hid.c b/tools/testing/selftests/bpf/prog_tests/hid.c
index 91543b8078ca..74426523dd6f 100644
--- a/tools/testing/selftests/bpf/prog_tests/hid.c
+++ b/tools/testing/selftests/bpf/prog_tests/hid.c
@@ -297,6 +297,68 @@ static int test_hid_raw_event(struct hid *hid_skel, int uhid_fd, int sysfs_fd)
return ret;
}

+/*
+ * Attach hid_set_get_data to the given uhid device,
+ * retrieve and open the matching hidraw node,
+ * inject one event in the uhid device,
+ * check that the program makes correct use of bpf_hid_{set|get}_data.
+ */
+static int test_hid_set_get_data(struct hid *hid_skel, int uhid_fd, int sysfs_fd)
+{
+ int err, hidraw_ino, hidraw_fd = -1;
+ char hidraw_path[64] = {0};
+ u8 buf[10] = {0};
+ int ret = -1;
+
+ /* attach hid_set_get_data program */
+ hid_skel->links.hid_set_get_data =
+ bpf_program__attach_hid(hid_skel->progs.hid_set_get_data, sysfs_fd);
+ if (!ASSERT_OK_PTR(hid_skel->links.hid_set_get_data,
+ "attach_hid(hid_set_get_data)"))
+ return PTR_ERR(hid_skel->links.hid_set_get_data);
+
+ hidraw_ino = get_hidraw(hid_skel->links.hid_set_get_data);
+ if (!ASSERT_GE(hidraw_ino, 0, "get_hidraw"))
+ goto cleanup;
+
+ /* open hidraw node to check the other side of the pipe */
+ sprintf(hidraw_path, "/dev/hidraw%d", hidraw_ino);
+ hidraw_fd = open(hidraw_path, O_RDWR | O_NONBLOCK);
+
+ if (!ASSERT_GE(hidraw_fd, 0, "open_hidraw"))
+ goto cleanup;
+
+ /* inject one event */
+ buf[0] = 1;
+ buf[1] = 42;
+ send_event(uhid_fd, buf, 6);
+
+ /* read the data from hidraw */
+ memset(buf, 0, sizeof(buf));
+ err = read(hidraw_fd, buf, sizeof(buf));
+ if (!ASSERT_EQ(err, 6, "read_hidraw"))
+ goto cleanup;
+
+ if (!ASSERT_EQ(buf[2], (42 >> 2), "hid_set_get_data"))
+ goto cleanup;
+
+ if (!ASSERT_EQ(buf[3], 1, "hid_set_get_data"))
+ goto cleanup;
+
+ if (!ASSERT_EQ(buf[4], 42, "hid_set_get_data"))
+ goto cleanup;
+
+ ret = 0;
+
+cleanup:
+ if (hidraw_fd >= 0)
+ close(hidraw_fd);
+
+ hid__detach(hid_skel);
+
+ return ret;
+}
+
/*
* Attach hid_rdesc_fixup to the given uhid device,
* retrieve and open the matching hidraw node,
@@ -395,6 +457,9 @@ void serial_test_hid_bpf(void)
err = test_hid_raw_event(hid_skel, uhid_fd, sysfs_fd);
ASSERT_OK(err, "hid");

+ err = test_hid_set_get_data(hid_skel, uhid_fd, sysfs_fd);
+ ASSERT_OK(err, "hid_set_get_data");
+
err = test_rdesc_fixup(hid_skel, uhid_fd, sysfs_fd);
ASSERT_OK(err, "hid_rdesc_fixup");

diff --git a/tools/testing/selftests/bpf/progs/hid.c b/tools/testing/selftests/bpf/progs/hid.c
index 2270448d0d3f..de6668471940 100644
--- a/tools/testing/selftests/bpf/progs/hid.c
+++ b/tools/testing/selftests/bpf/progs/hid.c
@@ -66,3 +66,48 @@ int hid_rdesc_fixup(struct hid_bpf_ctx *ctx)

return 0;
}
+
+SEC("hid/device_event")
+int hid_set_get_data(struct hid_bpf_ctx *ctx)
+{
+ int ret;
+ __u8 *buf;
+
+ buf = bpf_ringbuf_reserve(&ringbuf, 8, 0);
+ if (!buf)
+ return -12; /* -ENOMEM */
+
+ /* first try read/write with n > 32 */
+ ret = bpf_hid_get_data(ctx, 0, 64, buf, 8);
+ if (ret < 0)
+ goto discard;
+
+ /* reinject it */
+ ret = bpf_hid_set_data(ctx, 24, 64, buf, 8);
+ if (ret < 0)
+ goto discard;
+
+ /* extract data at bit offset 10 of size 4 (half a byte) */
+ ret = bpf_hid_get_data(ctx, 10, 4, buf, 8); /* expected to fail */
+ if (ret > 0) {
+ ret = -1;
+ goto discard;
+ }
+
+ ret = bpf_hid_get_data(ctx, 10, 4, buf, 4);
+ if (ret < 0)
+ goto discard;
+
+ /* reinject it */
+ ret = bpf_hid_set_data(ctx, 16, 4, buf, 4);
+ if (ret < 0)
+ goto discard;
+
+ ret = 0;
+
+ discard:
+
+ bpf_ringbuf_discard(buf, 0);
+
+ return ret;
+}
--
2.35.1