Here we add support for testing the attach and detach of a BPF program
to a tracepoint through tracefs.
Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
---
.../raw_tp_writable_test_ftrace_run.c | 89 +++++++++++++++++++
1 file changed, 89 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/raw_tp_writable_test_ftrace_run.c
diff --git a/tools/testing/selftests/bpf/prog_tests/raw_tp_writable_test_ftrace_run.c b/tools/testing/selftests/bpf/prog_tests/raw_tp_writable_test_ftrace_run.c
new file mode 100644
index 000000000000..7b42e3a69b71
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/raw_tp_writable_test_ftrace_run.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <test_progs.h>
+#include <linux/nbd.h>
+
+void test_raw_tp_writable_test_ftrace_run(void)
+{
+ __u32 duration = 0;
+ char error[4096];
+ int ret;
+
+ const struct bpf_insn trace_program[] = {
+ BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 42),
+ BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ };
+
+ struct bpf_load_program_attr load_attr = {
+ .prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
+ .license = "GPL v2",
+ .insns = trace_program,
+ .insns_cnt = sizeof(trace_program) / sizeof(struct bpf_insn),
+ .log_level = 2,
+ };
+
+ int bpf_fd = bpf_load_program_xattr(&load_attr, error, sizeof(error));
+
+ if (CHECK(bpf_fd < 0, "bpf_raw_tracepoint_writable loaded",
+ "failed: %d errno %d\n", bpf_fd, errno))
+ return;
+
+ const struct bpf_insn skb_program[] = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ };
+
+ struct bpf_load_program_attr skb_load_attr = {
+ .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
+ .license = "GPL v2",
+ .insns = skb_program,
+ .insns_cnt = sizeof(skb_program) / sizeof(struct bpf_insn),
+ };
+
+ int filter_fd =
+ bpf_load_program_xattr(&skb_load_attr, error, sizeof(error));
+ if (CHECK(filter_fd < 0, "test_program_loaded", "failed: %d errno %d\n",
+ filter_fd, errno))
+ goto out_bpffd;
+
+ ret = bpf_raw_tracepoint_ftrace_attach("bpf_test_run",
+ "bpf_test_finish",
+ bpf_fd);
+ if (CHECK(ret < 0, "bpf_raw_tracepoint_ftrace_attach",
+ "failed: %d errno %d\n", ret, errno))
+ goto out_filterfd;
+
+ char test_skb[128] = {
+ 0,
+ };
+
+ __u32 prog_ret;
+ int err = bpf_prog_test_run(filter_fd, 1, test_skb, sizeof(test_skb), 0,
+ 0, &prog_ret, 0);
+ CHECK(err != 42, "test_run",
+ "tracepoint did not modify return value\n");
+ CHECK(prog_ret != 0, "test_run_ret",
+ "socket_filter did not return 0\n");
+
+ ret = bpf_raw_tracepoint_ftrace_detach("bpf_test_run",
+ "bpf_test_finish",
+ bpf_fd);
+ if (CHECK(ret < 0, "bpf_raw_tracepoint_ftrace_detach",
+ "failed: %d errno %d\n", ret, errno))
+ goto out_filterfd;
+
+ err = bpf_prog_test_run(filter_fd, 1, test_skb, sizeof(test_skb), 0, 0,
+ &prog_ret, 0);
+ CHECK(err != 0, "test_run_notrace",
+ "test_run failed with %d errno %d\n", err, errno);
+ CHECK(prog_ret != 0, "test_run_ret_notrace",
+ "socket_filter did not return 0\n");
+
+out_filterfd:
+ close(filter_fd);
+out_bpffd:
+ close(bpf_fd);
+}
--
2.22.0.410.gd8fdbe21b5-goog
