Self tests added for new helper bpf_get_ns_current_pid_tgid
Signed-off-by: Carlos Neira <cneirabustos@xxxxxxxxx>
---
.../bpf/prog_tests/ns_current_pid_tgid.c | 88 +++++++++++++++++++
.../bpf/progs/test_ns_current_pid_tgid.c | 37 ++++++++
2 files changed, 125 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c
create mode 100644 tools/testing/selftests/bpf/progs/test_ns_current_pid_tgid.c
diff --git a/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c b/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c
new file mode 100644
index 000000000000..afd4a19dda14
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Carlos Neira cneirabustos@xxxxxxxxx */
+#include <test_progs.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+
+struct bss {
+ __u64 dev;
+ __u64 ino;
+ __u64 pid_tgid;
+ __u64 user_pid_tgid;
+};
+
+void test_ns_current_pid_tgid(void)
+{
+ const char *probe_name = "raw_tracepoint/sys_enter";
+ const char *file = "test_ns_current_pid_tgid.o";
+ int err, key = 0, duration = 0;
+ struct bpf_link *link = NULL;
+ struct bpf_program *prog;
+ struct bpf_map *bss_map;
+ struct bpf_object *obj;
+ struct bss bss;
+ struct stat st;
+ __u64 id;
+
+ obj = bpf_object__open_file(file, NULL);
+ if (CHECK(IS_ERR(obj), "obj_open", "err %ld\n", PTR_ERR(obj)))
+ return;
+
+ err = bpf_object__load(obj);
+ if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
+ goto cleanup;
+
+ bss_map = bpf_object__find_map_by_name(obj, "test_ns_.bss");
+ if (CHECK(!bss_map, "find_bss_map", "failed\n"))
+ goto cleanup;
+
+ prog = bpf_object__find_program_by_title(obj, probe_name);
+ if (CHECK(!prog, "find_prog", "prog '%s' not found\n",
+ probe_name))
+ goto cleanup;
+
+ memset(&bss, 0, sizeof(bss));
+ pid_t tid = syscall(SYS_gettid);
+ pid_t pid = getpid();
+
+ id = (__u64) tid << 32 | pid;
+ bss.user_pid_tgid = id;
+
+ if (CHECK_FAIL(stat("/proc/self/ns/pid", &st))) {
+ perror("Failed to stat /proc/self/ns/pid");
+ goto cleanup;
+ }
+
+ bss.dev = st.st_dev;
+ bss.ino = st.st_ino;
+
+ err = bpf_map_update_elem(bpf_map__fd(bss_map), &key, &bss, 0);
+ if (CHECK(err, "setting_bss", "failed to set bss : %d\n", err))
+ goto cleanup;
+
+ link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
+ if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n",
+ PTR_ERR(link))) {
+ link = NULL;
+ goto cleanup;
+ }
+
+ /* trigger some syscalls */
+ usleep(1);
+
+ err = bpf_map_lookup_elem(bpf_map__fd(bss_map), &key, &bss);
+ if (CHECK(err, "set_bss", "failed to get bss : %d\n", err))
+ goto cleanup;
+
+ if (CHECK(id != bss.pid_tgid, "Compare user pid/tgid vs. bpf pid/tgid",
+ "User pid/tgid %llu BPF pid/tgid %llu\n", id, bss.pid_tgid))
+ goto cleanup;
+cleanup:
+ if (!link) {
+ bpf_link__destroy(link);
+ link = NULL;
+ }
+ bpf_object__close(obj);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_ns_current_pid_tgid.c b/tools/testing/selftests/bpf/progs/test_ns_current_pid_tgid.c
new file mode 100644
index 000000000000..cdb77eb1a4fb
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_ns_current_pid_tgid.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Carlos Neira cneirabustos@xxxxxxxxx */
+
+#include <linux/bpf.h>
+#include <stdint.h>
+#include "bpf_helpers.h"
+
+static volatile struct {
+ __u64 dev;
+ __u64 ino;
+ __u64 pid_tgid;
+ __u64 user_pid_tgid;
+} res;
+
+SEC("raw_tracepoint/sys_enter")
+int trace(void *ctx)
+{
+ __u64 ns_pid_tgid, expected_pid;
+ struct bpf_pidns_info nsdata;
+ __u32 key = 0;
+
+ if (bpf_get_ns_current_pid_tgid(res.dev, res.ino, &nsdata,
+ sizeof(struct bpf_pidns_info)))
+ return 0;
+
+ ns_pid_tgid = (__u64)nsdata.tgid << 32 | nsdata.pid;
+ expected_pid = res.user_pid_tgid;
+
+ if (expected_pid != ns_pid_tgid)
+ return 0;
+
+ res.pid_tgid = ns_pid_tgid;
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.20.1
