2023-01-13 09:31:14

by Benjamin Tissoires

[permalink] [raw]
Subject: [PATCH HID for-next v2 3/9] selftests: hid: attach/detach 2 bpf programs, not just one

Add a second BPF program to attach to the device, as the development of
this feature showed that we also need to ensure we can detach multiple
programs to a device (hid_bpf_link->hid_table_index was actually not set
initially, and this lead to any BPF program not being released except for
the first one).

Signed-off-by: Benjamin Tissoires <[email protected]>

---

changes in v2:
- rewrote commit message s/->index/->hid_table_index/
---
tools/testing/selftests/hid/hid_bpf.c | 8 +++++++-
tools/testing/selftests/hid/progs/hid.c | 13 +++++++++++++
2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/hid/hid_bpf.c b/tools/testing/selftests/hid/hid_bpf.c
index 6615c26fb5dd..d215bb492eb4 100644
--- a/tools/testing/selftests/hid/hid_bpf.c
+++ b/tools/testing/selftests/hid/hid_bpf.c
@@ -616,6 +616,7 @@ TEST_F(hid_bpf, test_attach_detach)
{
const struct test_program progs[] = {
{ .name = "hid_first_event" },
+ { .name = "hid_second_event" },
};
__u8 buf[10] = {0};
int err;
@@ -634,7 +635,10 @@ TEST_F(hid_bpf, test_attach_detach)
ASSERT_EQ(buf[0], 1);
ASSERT_EQ(buf[2], 47);

- /* pin the program and immediately unpin it */
+ /* make sure both programs are run */
+ ASSERT_EQ(buf[3], 52);
+
+ /* pin the first program and immediately unpin it */
#define PIN_PATH "/sys/fs/bpf/hid_first_event"
bpf_program__pin(self->skel->progs.hid_first_event, PIN_PATH);
remove(PIN_PATH);
@@ -660,6 +664,7 @@ TEST_F(hid_bpf, test_attach_detach)
ASSERT_EQ(buf[0], 1);
ASSERT_EQ(buf[1], 47);
ASSERT_EQ(buf[2], 0);
+ ASSERT_EQ(buf[3], 0);

/* re-attach our program */

@@ -677,6 +682,7 @@ TEST_F(hid_bpf, test_attach_detach)
ASSERT_EQ(err, 6) TH_LOG("read_hidraw");
ASSERT_EQ(buf[0], 1);
ASSERT_EQ(buf[2], 47);
+ ASSERT_EQ(buf[3], 52);
}

/*
diff --git a/tools/testing/selftests/hid/progs/hid.c b/tools/testing/selftests/hid/progs/hid.c
index 6a86af0aa545..88c593f753b5 100644
--- a/tools/testing/selftests/hid/progs/hid.c
+++ b/tools/testing/selftests/hid/progs/hid.c
@@ -32,6 +32,19 @@ int BPF_PROG(hid_first_event, struct hid_bpf_ctx *hid_ctx)
return hid_ctx->size;
}

+SEC("?fmod_ret/hid_bpf_device_event")
+int BPF_PROG(hid_second_event, struct hid_bpf_ctx *hid_ctx)
+{
+ __u8 *rw_data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4 /* size */);
+
+ if (!rw_data)
+ return 0; /* EPERM check */
+
+ rw_data[3] = rw_data[2] + 5;
+
+ return hid_ctx->size;
+}
+
SEC("?fmod_ret/hid_bpf_device_event")
int BPF_PROG(hid_change_report_id, struct hid_bpf_ctx *hid_ctx)
{
--
2.38.1