When loading struct_ops programs kernel requires BTF id of the
struct_ops type and member index for attachment point inside that
type. This makes it not possible to have same BPF program used in
struct_ops maps that have different struct_ops type.
Check if libbpf rejects such BPF objects files.
Signed-off-by: Eduard Zingerman <eddyz87@xxxxxxxxx>
---
.../selftests/bpf/bpf_testmod/bpf_testmod.c | 24 +++++++++++
.../selftests/bpf/bpf_testmod/bpf_testmod.h | 4 ++
.../selftests/bpf/prog_tests/bad_struct_ops.c | 42 +++++++++++++++++++
.../selftests/bpf/progs/bad_struct_ops.c | 17 ++++++++
4 files changed, 87 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c
create mode 100644 tools/testing/selftests/bpf/progs/bad_struct_ops.c
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
index 0d8437e05f64..69f5eb9ad546 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
@@ -601,6 +601,29 @@ struct bpf_struct_ops bpf_bpf_testmod_ops = {
.owner = THIS_MODULE,
};
+static int bpf_dummy_reg2(void *kdata)
+{
+ struct bpf_testmod_ops2 *ops = kdata;
+
+ ops->test_1();
+ return 0;
+}
+
+static struct bpf_testmod_ops2 __bpf_testmod_ops2 = {
+ .test_1 = bpf_testmod_test_1,
+};
+
+struct bpf_struct_ops bpf_testmod_ops2 = {
+ .verifier_ops = &bpf_testmod_verifier_ops,
+ .init = bpf_testmod_ops_init,
+ .init_member = bpf_testmod_ops_init_member,
+ .reg = bpf_dummy_reg2,
+ .unreg = bpf_dummy_unreg,
+ .cfi_stubs = &__bpf_testmod_ops2,
+ .name = "bpf_testmod_ops2",
+ .owner = THIS_MODULE,
+};
+
extern int bpf_fentry_test1(int a);
static int bpf_testmod_init(void)
@@ -612,6 +635,7 @@ static int bpf_testmod_init(void)
ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_testmod_kfunc_set);
ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &bpf_testmod_kfunc_set);
ret = ret ?: register_bpf_struct_ops(&bpf_bpf_testmod_ops, bpf_testmod_ops);
+ ret = ret ?: register_bpf_struct_ops(&bpf_testmod_ops2, bpf_testmod_ops2);
if (ret < 0)
return ret;
if (bpf_fentry_test1(0) < 0)
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
index c3b0cf788f9f..3183fff7f246 100644
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h
@@ -37,4 +37,8 @@ struct bpf_testmod_ops {
int (*test_maybe_null)(int dummy, struct task_struct *task);
};
+struct bpf_testmod_ops2 {
+ int (*test_1)(void);
+};
+
#endif /* _BPF_TESTMOD_H */
diff --git a/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c b/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c
new file mode 100644
index 000000000000..9c689db4b05b
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/bad_struct_ops.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <test_progs.h>
+#include "bad_struct_ops.skel.h"
+
+#define EXPECTED_MSG "libbpf: struct_ops reloc"
+
+static libbpf_print_fn_t old_print_cb;
+static bool msg_found;
+
+static int print_cb(enum libbpf_print_level level, const char *fmt, va_list args)
+{
+ old_print_cb(level, fmt, args);
+ if (level == LIBBPF_WARN && strncmp(fmt, EXPECTED_MSG, strlen(EXPECTED_MSG)) == 0)
+ msg_found = true;
+
+ return 0;
+}
+
+static void test_bad_struct_ops(void)
+{
+ struct bad_struct_ops *skel;
+ int err;
+
+ old_print_cb = libbpf_set_print(print_cb);
+ skel = bad_struct_ops__open_and_load();
+ err = errno;
+ libbpf_set_print(old_print_cb);
+ if (!ASSERT_NULL(skel, "bad_struct_ops__open_and_load"))
+ return;
+
+ ASSERT_EQ(err, EINVAL, "errno should be EINVAL");
+ ASSERT_TRUE(msg_found, "expected message");
+
+ bad_struct_ops__destroy(skel);
+}
+
+void serial_test_bad_struct_ops(void)
+{
+ if (test__start_subtest("test_bad_struct_ops"))
+ test_bad_struct_ops();
+}
diff --git a/tools/testing/selftests/bpf/progs/bad_struct_ops.c b/tools/testing/selftests/bpf/progs/bad_struct_ops.c
new file mode 100644
index 000000000000..9c103afbfdb1
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bad_struct_ops.c
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "../bpf_testmod/bpf_testmod.h"
+
+char _license[] SEC("license") = "GPL";
+
+SEC("struct_ops/test_1")
+int BPF_PROG(test_1) { return 0; }
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops testmod_1 = { .test_1 = (void *)test_1 };
+
+SEC(".struct_ops.link")
+struct bpf_testmod_ops2 testmod_2 = { .test_1 = (void *)test_1 };
--
2.43.0
