[PATCH bpf-next v3 3/3] selftests/bpf: add test for legacy/perf kprobe/uprobe attach mode

From: menglong8 . dong
Date: Mon Feb 20 2023 - 21:55:22 EST


From: Menglong Dong <imagedong@xxxxxxxxxxx>

Add the testing for kprobe/uprobe attaching in default, legacy, perf and
link mode. And the testing passed:

./test_progs -t attach_probe
$5/1 attach_probe/manual-default:OK
$5/2 attach_probe/manual-legacy:OK
$5/3 attach_probe/manual-perf:OK
$5/4 attach_probe/manual-link:OK
$5/5 attach_probe/auto:OK
$5/6 attach_probe/kprobe-sleepable:OK
$5/7 attach_probe/uprobe-lib:OK
$5/8 attach_probe/uprobe-sleepable:OK
$5/9 attach_probe/uprobe-ref_ctr:OK
$5 attach_probe:OK
Summary: 1/9 PASSED, 0 SKIPPED, 0 FAILED

Reviewed-by: Biao Jiang <benbjiang@xxxxxxxxxxx>
Signed-off-by: Menglong Dong <imagedong@xxxxxxxxxxx>
Reviewed-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
---
.../selftests/bpf/prog_tests/attach_probe.c | 54 ++++++++++++++-----
.../selftests/bpf/progs/test_attach_probe.c | 32 -----------
.../bpf/progs/test_attach_probe_manual.c | 53 ++++++++++++++++++
3 files changed, 93 insertions(+), 46 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_attach_probe_manual.c

diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
index 8afd3e6066b8..e71cb44bf2e7 100644
--- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
+++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "test_attach_kprobe_sleepable.skel.h"
+#include "test_attach_probe_manual.skel.h"
#include "test_attach_probe.skel.h"

/* this is how USDT semaphore is actually defined, except volatile modifier */
@@ -33,33 +34,48 @@ static noinline void trigger_func4(void)
static char test_data[] = "test_data";

/* manual attach kprobe/kretprobe/uprobe/uretprobe testings */
-static void test_attach_probe_manual(struct test_attach_probe *skel)
+static void test_attach_probe_manual(enum probe_attach_mode attach_mode)
{
DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
+ DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, kprobe_opts);
struct bpf_link *kprobe_link, *kretprobe_link;
struct bpf_link *uprobe_link, *uretprobe_link;
+ struct test_attach_probe_manual *skel;
ssize_t uprobe_offset;

+ skel = test_attach_probe_manual__open();
+ if (!ASSERT_OK_PTR(skel, "skel_kprobe_manual_open"))
+ return;
+
+ if (!ASSERT_OK(test_attach_probe_manual__load(skel), "skel_manual_load"))
+ goto cleanup;
+ if (!ASSERT_OK_PTR(skel->bss, "manual_check_bss"))
+ goto cleanup;
+
uprobe_offset = get_uprobe_offset(&trigger_func);
if (!ASSERT_GE(uprobe_offset, 0, "uprobe_offset"))
- return;
+ goto cleanup;

/* manual-attach kprobe/kretprobe */
- kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
- false /* retprobe */,
- SYS_NANOSLEEP_KPROBE_NAME);
+ kprobe_opts.attach_mode = attach_mode;
+ kprobe_opts.retprobe = false;
+ kprobe_link = bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe,
+ SYS_NANOSLEEP_KPROBE_NAME,
+ &kprobe_opts);
if (!ASSERT_OK_PTR(kprobe_link, "attach_kprobe"))
- return;
+ goto cleanup;
skel->links.handle_kprobe = kprobe_link;

- kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
- true /* retprobe */,
- SYS_NANOSLEEP_KPROBE_NAME);
+ kprobe_opts.retprobe = true;
+ kretprobe_link = bpf_program__attach_kprobe_opts(skel->progs.handle_kretprobe,
+ SYS_NANOSLEEP_KPROBE_NAME,
+ &kprobe_opts);
if (!ASSERT_OK_PTR(kretprobe_link, "attach_kretprobe"))
- return;
+ goto cleanup;
skel->links.handle_kretprobe = kretprobe_link;

/* manual-attach uprobe/uretprobe */
+ uprobe_opts.attach_mode = attach_mode;
uprobe_opts.ref_ctr_offset = 0;
uprobe_opts.retprobe = false;
uprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe,
@@ -68,7 +84,7 @@ static void test_attach_probe_manual(struct test_attach_probe *skel)
uprobe_offset,
&uprobe_opts);
if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe"))
- return;
+ goto cleanup;
skel->links.handle_uprobe = uprobe_link;

uprobe_opts.retprobe = true;
@@ -77,7 +93,7 @@ static void test_attach_probe_manual(struct test_attach_probe *skel)
"/proc/self/exe",
uprobe_offset, &uprobe_opts);
if (!ASSERT_OK_PTR(uretprobe_link, "attach_uretprobe"))
- return;
+ goto cleanup;
skel->links.handle_uretprobe = uretprobe_link;

/* attach uprobe by function name manually */
@@ -106,6 +122,9 @@ static void test_attach_probe_manual(struct test_attach_probe *skel)
ASSERT_EQ(skel->bss->uprobe_res, 3, "check_uprobe_res");
ASSERT_EQ(skel->bss->uretprobe_res, 4, "check_uretprobe_res");
ASSERT_EQ(skel->bss->uprobe_byname_res, 5, "check_uprobe_byname_res");
+
+cleanup:
+ test_attach_probe_manual__destroy(skel);
}

static void test_attach_probe_auto(struct test_attach_probe *skel)
@@ -287,8 +306,15 @@ void test_attach_probe(void)
if (!ASSERT_OK_PTR(skel->bss, "check_bss"))
goto cleanup;

- if (test__start_subtest("manual"))
- test_attach_probe_manual(skel);
+ if (test__start_subtest("manual-default"))
+ test_attach_probe_manual(PROBE_ATTACH_MODE_DEFAULT);
+ if (test__start_subtest("manual-legacy"))
+ test_attach_probe_manual(PROBE_ATTACH_MODE_LEGACY);
+ if (test__start_subtest("manual-perf"))
+ test_attach_probe_manual(PROBE_ATTACH_MODE_PERF);
+ if (test__start_subtest("manual-link"))
+ test_attach_probe_manual(PROBE_ATTACH_MODE_LINK);
+
if (test__start_subtest("auto"))
test_attach_probe_auto(skel);
if (test__start_subtest("kprobe-sleepable"))
diff --git a/tools/testing/selftests/bpf/progs/test_attach_probe.c b/tools/testing/selftests/bpf/progs/test_attach_probe.c
index 9e1e7163bb67..68466a6ad18c 100644
--- a/tools/testing/selftests/bpf/progs/test_attach_probe.c
+++ b/tools/testing/selftests/bpf/progs/test_attach_probe.c
@@ -7,12 +7,8 @@
#include <bpf/bpf_core_read.h>
#include "bpf_misc.h"

-int kprobe_res = 0;
int kprobe2_res = 0;
-int kretprobe_res = 0;
int kretprobe2_res = 0;
-int uprobe_res = 0;
-int uretprobe_res = 0;
int uprobe_byname_res = 0;
int uretprobe_byname_res = 0;
int uprobe_byname2_res = 0;
@@ -23,13 +19,6 @@ int uretprobe_byname3_sleepable_res = 0;
int uretprobe_byname3_res = 0;
void *user_ptr = 0;

-SEC("kprobe")
-int handle_kprobe(struct pt_regs *ctx)
-{
- kprobe_res = 1;
- return 0;
-}
-
SEC("ksyscall/nanosleep")
int BPF_KSYSCALL(handle_kprobe_auto, struct __kernel_timespec *req, struct __kernel_timespec *rem)
{
@@ -37,13 +26,6 @@ int BPF_KSYSCALL(handle_kprobe_auto, struct __kernel_timespec *req, struct __ker
return 0;
}

-SEC("kretprobe")
-int handle_kretprobe(struct pt_regs *ctx)
-{
- kretprobe_res = 2;
- return 0;
-}
-
SEC("kretsyscall/nanosleep")
int BPF_KRETPROBE(handle_kretprobe_auto, int ret)
{
@@ -51,20 +33,6 @@ int BPF_KRETPROBE(handle_kretprobe_auto, int ret)
return ret;
}

-SEC("uprobe")
-int handle_uprobe(struct pt_regs *ctx)
-{
- uprobe_res = 3;
- return 0;
-}
-
-SEC("uretprobe")
-int handle_uretprobe(struct pt_regs *ctx)
-{
- uretprobe_res = 4;
- return 0;
-}
-
SEC("uprobe")
int handle_uprobe_ref_ctr(struct pt_regs *ctx)
{
diff --git a/tools/testing/selftests/bpf/progs/test_attach_probe_manual.c b/tools/testing/selftests/bpf/progs/test_attach_probe_manual.c
new file mode 100644
index 000000000000..7f08bce94596
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_attach_probe_manual.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017 Facebook
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
+#include "bpf_misc.h"
+
+int kprobe_res = 0;
+int kretprobe_res = 0;
+int uprobe_res = 0;
+int uretprobe_res = 0;
+int uprobe_byname_res = 0;
+void *user_ptr = 0;
+
+SEC("kprobe")
+int handle_kprobe(struct pt_regs *ctx)
+{
+ kprobe_res = 1;
+ return 0;
+}
+
+SEC("kretprobe")
+int handle_kretprobe(struct pt_regs *ctx)
+{
+ kretprobe_res = 2;
+ return 0;
+}
+
+SEC("uprobe")
+int handle_uprobe(struct pt_regs *ctx)
+{
+ uprobe_res = 3;
+ return 0;
+}
+
+SEC("uretprobe")
+int handle_uretprobe(struct pt_regs *ctx)
+{
+ uretprobe_res = 4;
+ return 0;
+}
+
+SEC("uprobe")
+int handle_uprobe_byname(struct pt_regs *ctx)
+{
+ uprobe_byname_res = 5;
+ return 0;
+}
+
+
+char _license[] SEC("license") = "GPL";
--
2.39.0