Now that we can call some kfuncs from BPF_PROG_TYPE_SYSCALL progs, let's
add some selftests that verify as much. As a bonus, let's also verify
that we can't call the progs from raw tracepoints. Do do this, we add a
new selftest suite called verifier_kfunc_prog_types.
Acked-by: Yonghong Song <yonghong.song@xxxxxxxxx>
Signed-off-by: David Vernet <void@xxxxxxxxxxxxx>
---
.../prog_tests/verifier_kfunc_prog_types.c | 11 ++
.../selftests/bpf/progs/cgrp_kfunc_common.h | 2 +-
.../selftests/bpf/progs/task_kfunc_common.h | 2 +-
.../bpf/progs/verifier_kfunc_prog_types.c | 119 ++++++++++++++++++
4 files changed, 132 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/verifier_kfunc_prog_types.c
create mode 100644 tools/testing/selftests/bpf/progs/verifier_kfunc_prog_types.c
diff --git a/tools/testing/selftests/bpf/prog_tests/verifier_kfunc_prog_types.c b/tools/testing/selftests/bpf/prog_tests/verifier_kfunc_prog_types.c
new file mode 100644
index 000000000000..3918ecc2ee91
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/verifier_kfunc_prog_types.c
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
+
+#include <test_progs.h>
+
+#include "verifier_kfunc_prog_types.skel.h"
+
+void test_verifier_kfunc_prog_types(void)
+{
+ RUN_TESTS(verifier_kfunc_prog_types);
+}
diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h b/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h
index 22914a70db54..73ba32e9a693 100644
--- a/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h
+++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h
@@ -13,7 +13,7 @@ struct __cgrps_kfunc_map_value {
struct cgroup __kptr * cgrp;
};
-struct hash_map {
+struct {
__uint(type, BPF_MAP_TYPE_HASH);
__type(key, int);
__type(value, struct __cgrps_kfunc_map_value);
diff --git a/tools/testing/selftests/bpf/progs/task_kfunc_common.h b/tools/testing/selftests/bpf/progs/task_kfunc_common.h
index 41f2d44f49cb..6720c4b5be41 100644
--- a/tools/testing/selftests/bpf/progs/task_kfunc_common.h
+++ b/tools/testing/selftests/bpf/progs/task_kfunc_common.h
@@ -13,7 +13,7 @@ struct __tasks_kfunc_map_value {
struct task_struct __kptr * task;
};
-struct hash_map {
+struct {
__uint(type, BPF_MAP_TYPE_HASH);
__type(key, int);
__type(value, struct __tasks_kfunc_map_value);
diff --git a/tools/testing/selftests/bpf/progs/verifier_kfunc_prog_types.c b/tools/testing/selftests/bpf/progs/verifier_kfunc_prog_types.c
new file mode 100644
index 000000000000..b7f17c6b3443
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_kfunc_prog_types.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
+
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+
+#include "bpf_misc.h"
+#include "cgrp_kfunc_common.h"
+#include "cpumask_common.h"
+#include "task_kfunc_common.h"
+
+char _license[] SEC("license") = "GPL";
+
+/***************
+ * Task kfuncs *
+ ***************/
+
+static inline void task_kfunc_load_test(void)
+{
+ struct task_struct *current, *ref_1, *ref_2;
+
+ current = bpf_get_current_task_btf();
+ ref_1 = bpf_task_from_pid(current->pid);
+ if (!ref_1)
+ return;
+
+ ref_2 = bpf_task_acquire(ref_1);
+ if (ref_2)
+ bpf_task_release(ref_2);
+ bpf_task_release(ref_1);
+}
+
+SEC("raw_tp")
+__failure __msg("calling kernel function")
+int BPF_PROG(task_kfunc_raw_tp)
+{
+ task_kfunc_load_test();
+ return 0;
+}
+
+SEC("syscall") __success
+int BPF_PROG(task_kfunc_syscall)
+{
+ task_kfunc_load_test();
+ return 0;
+}
+
+/*****************
+ * cgroup kfuncs *
+ *****************/
+
+static inline void cgrp_kfunc_load_test(void)
+{
+ struct cgroup *cgrp, *ref;
+
+ cgrp = bpf_cgroup_from_id(0);
+ if (!cgrp)
+ return;
+
+ ref = bpf_cgroup_acquire(cgrp);
+ if (!ref) {
+ bpf_cgroup_release(cgrp);
+ return;
+ }
+
+ bpf_cgroup_release(ref);
+ bpf_cgroup_release(cgrp);
+}
+
+SEC("raw_tp")
+__failure __msg("calling kernel function")
+int BPF_PROG(cgrp_kfunc_raw_tp)
+{
+ cgrp_kfunc_load_test();
+ return 0;
+}
+
+SEC("syscall") __success
+int BPF_PROG(cgrp_kfunc_syscall)
+{
+ cgrp_kfunc_load_test();
+ return 0;
+}
+
+/******************
+ * cpumask kfuncs *
+ ******************/
+
+static inline void cpumask_kfunc_load_test(void)
+{
+ struct bpf_cpumask *alloc, *ref;
+
+ alloc = bpf_cpumask_create();
+ if (!alloc)
+ return;
+
+ ref = bpf_cpumask_acquire(alloc);
+ bpf_cpumask_set_cpu(0, alloc);
+ bpf_cpumask_test_cpu(0, (const struct cpumask *)ref);
+
+ bpf_cpumask_release(ref);
+ bpf_cpumask_release(alloc);
+}
+
+SEC("raw_tp")
+__failure __msg("calling kernel function")
+int BPF_PROG(cpumask_kfunc_raw_tp)
+{
+ cpumask_kfunc_load_test();
+ return 0;
+}
+
+SEC("syscall") __success
+int BPF_PROG(cpumask_kfunc_syscall)
+{
+ cpumask_kfunc_load_test();
+ return 0;
+}
--
2.44.0
