Commit e5fb60ee authored by Toke Høiland-Jørgensen's avatar Toke Høiland-Jørgensen Committed by Daniel Borkmann

selftests: Add test for overriding global data value before load

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: default avatarToke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329132253.232541-2-toke@redhat.com
parent e2842be5
// 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);
}
...@@ -68,7 +68,7 @@ static struct foo struct3 = { ...@@ -68,7 +68,7 @@ static struct foo struct3 = {
bpf_map_update_elem(&result_##map, &key, var, 0); \ bpf_map_update_elem(&result_##map, &key, var, 0); \
} while (0) } while (0)
SEC("static_data_load") SEC("classifier/static_data_load")
int load_static_data(struct __sk_buff *skb) int load_static_data(struct __sk_buff *skb)
{ {
static const __u64 bar = ~0; static const __u64 bar = ~0;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment