This adds a test to exercise the new bpf_map__set_initial_value() function.
The test simply overrides the global data section with all zeroes, and
checks that the new value makes it into the kernel map on load.
Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
---
.../bpf/prog_tests/global_data_init.c | 61 +++++++++++++++++++
.../selftests/bpf/progs/test_global_data.c | 2 +-
2 files changed, 62 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/global_data_init.c
diff --git a/tools/testing/selftests/bpf/prog_tests/global_data_init.c b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
new file mode 100644
index 000000000000..3bdaa5a40744
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+
+void test_global_data_init(void)
+{
+ const char *file = "./test_global_data.o";
+ int err = -ENOMEM, map_fd, zero = 0;
+ __u8 *buff = NULL, *newval = NULL;
+ struct bpf_object *obj;
+ struct bpf_map *map;
+ __u32 duration = 0;
+ size_t sz;
+
+ obj = bpf_object__open_file(file, NULL);
+ if (CHECK_FAIL(!obj))
+ return;
+
+ map = bpf_object__find_map_by_name(obj, "test_glo.rodata");
+ if (CHECK_FAIL(!map || !bpf_map__is_internal(map)))
+ goto out;
+
+ sz = bpf_map__def(map)->value_size;
+ newval = malloc(sz);
+ if (CHECK_FAIL(!newval))
+ goto out;
+
+ memset(newval, 0, sz);
+ /* wrong size, should fail */
+ err = bpf_map__set_initial_value(map, newval, sz - 1);
+ if (CHECK(!err, "reject set initial value wrong size", "err %d\n", err))
+ goto out;
+
+ err = bpf_map__set_initial_value(map, newval, sz);
+ if (CHECK(err, "set initial value", "err %d\n", err))
+ goto out;
+
+ err = bpf_object__load(obj);
+ if (CHECK_FAIL(err))
+ goto out;
+
+ map_fd = bpf_map__fd(map);
+ if (CHECK_FAIL(map_fd < 0))
+ goto out;
+
+ buff = malloc(sz);
+ if (buff)
+ err = bpf_map_lookup_elem(map_fd, &zero, buff);
+ if (CHECK(!buff || err || memcmp(buff, newval, sz),
+ "compare .rodata map data override",
+ "err %d errno %d\n", err, errno))
+ goto out;
+
+ memset(newval, 1, sz);
+ /* object loaded - should fail */
+ err = bpf_map__set_initial_value(map, newval, sz);
+ CHECK(!err, "reject set initial value after load", "err %d\n", err);
+out:
+ free(buff);
+ free(newval);
+ bpf_object__close(obj);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_global_data.c b/tools/testing/selftests/bpf/progs/test_global_data.c
index dd7a4d3dbc0d..1319be1c54ba 100644
--- a/tools/testing/selftests/bpf/progs/test_global_data.c
+++ b/tools/testing/selftests/bpf/progs/test_global_data.c
@@ -68,7 +68,7 @@ static struct foo struct3 = {
bpf_map_update_elem(&result_##map, &key, var, 0); \
} while (0)
-SEC("static_data_load")
+SEC("classifier/static_data_load")
int load_static_data(struct __sk_buff *skb)
{
static const __u64 bar = ~0;
--
2.26.0
