[PATCH bpf-next 2/2] selftests/bpf: Test BPF_KPROBE_SYSCALL/BPF_KRETPROBE_SYSCALL macros

From: Hengqi Chen <hengqi.chen@gmail.com>
To: bpf@vger.kernel.org, andrii@kernel.org, hengqi.chen@gmail.com
Subject: [PATCH bpf-next 2/2] selftests/bpf: Test BPF_KPROBE_SYSCALL/BPF_KRETPROBE_SYSCALL macros
Date: Tue, 21 Dec 2021 05:53:12 +0000	[thread overview]
Message-ID: <20211221055312.3371414-3-hengqi.chen@gmail.com> (raw)
In-Reply-To: <20211221055312.3371414-1-hengqi.chen@gmail.com>

Add tests for the newly added BPF_KPROBE_SYSCALL/BPF_KRETPROBE_SYSCALL macros.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
---
 .../selftests/bpf/prog_tests/kprobe_syscall.c | 40 ++++++++++++++++++
 .../selftests/bpf/progs/test_kprobe_syscall.c | 41 +++++++++++++++++++
 2 files changed, 81 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c
 create mode 100644 tools/testing/selftests/bpf/progs/test_kprobe_syscall.c

diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c
new file mode 100644
index 000000000000..a1fad70bbb69
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Hengqi Chen */
+
+#include <test_progs.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include "test_kprobe_syscall.skel.h"
+
+void test_kprobe_syscall(void)
+{
+	struct test_kprobe_syscall *skel;
+	int err, fd = 0;
+
+	skel = test_kprobe_syscall__open();
+	if (!ASSERT_OK_PTR(skel, "could not open BPF object"))
+		return;
+
+	skel->rodata->my_pid = getpid();
+
+	err = test_kprobe_syscall__load(skel);
+	if (!ASSERT_OK(err, "could not load BPF object"))
+		goto cleanup;
+
+	err = test_kprobe_syscall__attach(skel);
+	if (!ASSERT_OK(err, "could not attach BPF object"))
+		goto cleanup;
+
+	fd = socket(AF_UNIX, SOCK_STREAM, 0);
+
+	ASSERT_GT(fd, 0, "socket failed");
+	ASSERT_EQ(skel->bss->domain, AF_UNIX, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->type, SOCK_STREAM, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->protocol, 0, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->fd, fd, "BPF_KRETPROBE_SYSCALL failed");
+
+cleanup:
+	if (fd)
+		close(fd);
+	test_kprobe_syscall__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_kprobe_syscall.c b/tools/testing/selftests/bpf/progs/test_kprobe_syscall.c
new file mode 100644
index 000000000000..ecef9d19007c
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_kprobe_syscall.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Hengqi Chen */
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
+
+const volatile pid_t my_pid = 0;
+int domain = 0;
+int type = 0;
+int protocol = 0;
+int fd = 0;
+
+SEC("kprobe/__x64_sys_socket")
+int BPF_KPROBE_SYSCALL(socket_enter, int d, int t, int p)
+{
+	pid_t pid = bpf_get_current_pid_tgid() >> 32;
+
+	if (pid != my_pid)
+		return 0;
+
+	domain = d;
+	type = t;
+	protocol = p;
+	return 0;
+}
+
+SEC("kretprobe/__x64_sys_socket")
+int BPF_KRETPROBE_SYSCALL(socket_exit, int ret)
+{
+	pid_t pid = bpf_get_current_pid_tgid() >> 32;
+
+	if (pid != my_pid)
+		return 0;
+
+	fd = ret;
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.30.2
